ACTINIC RADIATION-CURING TYPE INK SET, INKJET RECORDING METHOD, AND PRINTED MATERIAL CROSS-REFERNCE TO RELATED APPLICATION This application claims priority under 35 USC 119 from Japanese Patent Application No. 2012-047974 filed on March 5, 2012, the disclosure of which is incorporated by reference herein. TECHNICAL FIELD The present invention relates to an actinic radiation-curing type ink set, an inkjet recording method, and a printed material. BACKGROUND ART As image recording methods for forming an image on a recording medium such as paper based on an image data signal, there are an electrophotographic system, sublimation type and melt type thermal transfer systems, an inkjet system, etc. With regard to the inkjet system, the printing equipment is inexpensive, it is not necessary to use a plate when printing, and since an image is formed directly on a recording medium by discharging an ink composition only on a required image area, the ink composition can be used efficiently and the running cost is low, particularly in the case of small lot production. Furthermore, there is little noise and it is excellent as an image recording system, and has been attracting attention in recent years. Among them, an inkjet recording ink composition (radiation-curing inkjet recording ink composition), which is curable upon exposure to radiation such as UV rays, is an excellent system from the viewpoint of it being possible to print on various types of recording media because, compared with a solvent-based ink composition, the drying properties are excellent and an image is resistant to spreading since the majority of the components in the ink composition cure upon exposure to radiation such as UV rays. Various radiation curing ink compositions have previously been proposed; JP-A-2007-131755 (JP-A denotes a Japanese unexamined patent application publication) describes an actinic radiation curable ink for ink jet comprising a polymerizable monomer, the polymerizable monomer comprising a monofunctional monomer at 80 mass% to 99.99 mass% and a polyfunctional monomer at 20 mass% to 0.01 mass% relative to the entire monomer, and the percentage change of mass of a cured film of said ink when immersed in said ink for 30 seconds being no greater than 30 mass%. Currently, when printing is carried out using an ink jet printer by firing ink droplets onto plain paper or a non-water absorbing recording medium such as a plastic, higher speed, higher image quality, and fixation onto the recording medium are important objects. JP-A-2008-100501 discloses an ink set for ink jet recording for the purpose of improving image uniformity, etc. between various recording media, the ink set comprising at least a colored liquid composition comprising at least a polymerizable compound, a photopolymerization initiator, and a colorant and an undercoat liquid composition comprising at least a polymerizable compound and a photopolymerization initiator, the polymerizable compound contained in the colored liquid composition comprising at least one type of monofunctional monomer and at least one type of polyfunctional monomer, the amount of monofunctional monomer in the entire colored liquid composition being 10 to 70 mass%, and the amount of polyfunctional monomer being 10 to 50 mass%. Furthermore, improving the durability, etc. of a printed material is also an object. JP-A-2010-000788 discloses an ink jet printed material for the purpose of obtaining an ink jet printed material having excellent weatherability and durability, the ink jet printed material having a transparent protective layer formed on the surface, the ink jet printed material comprising a substrate and a picture layer formed above the substrate by ink jet type printing, the transparent protective layer being formed above the picture layer, the picture layer comprising a UV-curable resin ink that cures upon irradiation with UV, and the transparent protective layer comprising an electron beam-curable resin that cures upon irradiation with an electron beam. SUMMARY OF INVENTION It is an object of the present invention to provide an actinic radiation-curing type ink set that can form an ink image having excellent surface gloss and excellent blocking resistance and stretchability, and provide an inkjet recording method using the ink set and a printed material recorded by the inkjet recording method. In particular, up until now, with regard to an actinic radiation-curing type inkjet ink printer using a clear ink, in a multipass mode of a shuttle scanning type printer a good surface state cannot be obtained and the surface gloss is insufficient. The objects have been attained by means described in <1>, <16>, <21>, or <22> below. They are described below together with <2> to <15> and <17> to <20>, which are preferred embodiments. <1> An actinic radiation-curing type ink set comprising a colored ink composition and a clear ink composition (C1), the colored ink composition comprising (Component A1) a radically polymerizable compound, (Component B1) a polymerization initiator, and (Component D) a colorant, and the clear ink composition (C1) comprising (Component A2) a radically polymerizable compound, (Component B2) a polymerization initiator, and (Component S) an organic solvent, <2> the actinic radiation-curing type ink set according to <1>, wherein it further comprises a clear ink composition (C2) that does not comprise an organic solvent, <3> the actinic radiation-curing type ink set according to <2>, wherein the clear ink composition (C2) comprises (Component A3) a radically polymerizable compound and (Component B3) a polymerization initiator, <4> the actinic radiation-curing type ink set according to <3>, wherein the colored ink composition comprises at least a bisacylphosphine oxide as the polymerization initiator, and the clear ink composition (C1) and/or the clear ink composition (C2) comprise a monoacylphosphine oxide as the polymerization initiator, <5> the actinic radiation-curing type ink set according to any one of <1> to <4>, wherein the colored ink composition does not contain an organic solvent, <6> the actinic radiation-curing type ink set according to any one of <1> to <5>, wherein the actinic radiation-curing type ink set is for forming multiple layers, <7> the actinic radiation-curing type ink set according to any one of <1> to <6>, wherein the colored ink composition comprises (Component A1-1) an N- vinyl compound as Component A1, <8> the actinic radiation-curing type ink set according to <7>, wherein Component A1-1 is /V-vinylcaprolactam, <9> the actinic radiation-curing type ink set according to any one of <1> to <8>, wherein said Component S comprises at least one type selected from the group consisting of an alcohol, a polyhydric alcohol, a polyhydric alcohol ether, a nitrogen-containing compound, and a sulfur-containing compound, <10> the actinic radiation-curing type ink set according to any one of <1> to <9>, wherein said Component S comprises at least one type selected from the group consisting of an alcohol, a polyhydric alcohol, and a polyhydric alcohol ether, <11> the actinic radiation-curing type ink set according to any one of <1> to <10>, wherein said Component S has a boiling point of 65°C to 250°C, <12> the actinic radiation-curing type ink set according to any one of <1> to <11>, wherein said Component S has a content in the clear ink composition (C1)of 1 to80mass%, <13> the actinic radiation-curing type ink set according to any one of <1> to <12>, wherein said Component S comprises at least one type selected from the group consisting of methanol, isopropyl alcohol, 1-butyl alcohol, 1-ethoxy- 2-propanol, ethylene glycol monomethyl ether, and diethylene glycol monobutyl ether, <14> the actinic radiation-curing type ink set according to any one of <1> to <13>, wherein the colored ink composition comprises (Component A1-2) a compound represented by Formula (a-2) as Component A1, wherein in Formula (a-2), R1, R2, and R3 independently denote a hydrogen atom, a methyl group, or an ethyl group and X2 denotes a single bond or a divalent linking group, <15> the actinic radiation-curing type ink set according to any one of <1> to <14>, wherein the colored ink composition comprises a monofunctional radically polymerizable compound at 60 to 100 mass% relative to the total amount of Component A1, <16> an inkjet recording method using the actinic radiation-curing type ink set according to any one of <1> to <15>, the method comprising, in this order, an image formation step of forming a color image by discharging the colored ink composition onto a recording medium and a clear ink layer formation step of forming a clear ink layer by discharging the clear ink composition (C1), <17> the inkjet recording method according to <16>, wherein it further comprises a step of heating the recording medium at 30°C to 80°C subsequent to the clear ink layer formation step, <18> the inkjet recording method according to <16> or <17>, wherein it comprises a scanning step of moving, in a first direction relative to the recording medium, an inkjet head having a plurality of nozzle arrays comprising a first nozzle array having a plurality of nozzles arranged for discharging the colored ink composition and a second nozzle array having a plurality of nozzles arranged for discharging the clear ink composition (C1), a relative movement step of reciprocating the recording medium relative to the inkjet head in a second direction that is not parallel to the first direction, a discharge control step of dividing the nozzle array into a plurality of regions in the second direction and controlling ink discharge from the inkjet head for each divided nozzle region unit, and an actinic radiation irradiation step of irradiating with actinic radiation the ink that has been discharged from the inkjet head in the discharge control step and has been deposited on the recording medium, the actinic radiation irradiation step being a step of carrying out the irradiation with actinic radiation by dividing the actinic radiation irradiation area into a plurality of regions so as to correspond to the divided nozzle regions and controlling the amount of light for each region of the divided irradiation regions, <19> the inkjet recording method according to <18>, wherein the actinic radiation irradiation area is divided into two regions, the illumination intensity of an irradiation light source for the first region is 100 mW/cm2 to 800 mW/cm2 and the illumination intensity of an irradiation light source for the second region is 800 mW/cm2 to 1,600 mW/cm2, <20> the inkjet recording method according to any one of <16> to <19>, wherein the minimum droplet volume for discharging the colored ink composition is at least 5 pL but less than 20 pL, and the minimum droplet volume for discharging the clear ink composition (C1) is at least 20 pL but no greater than 60 pL, <21> a printed material obtained by the method according to any one of <16>to <20>, and <22> use of the actinic radiation-curing type ink set according to any one of <1> to <15> as an actinic radiation-curing type inkjet ink set for formation of multiple layers. In accordance with the present invention, there can be provided an actinic radiation-curing type ink set that can form an ink image having excellent surface gloss and excellent blocking resistance and stretchability, and in addition thereto there can be provided an inkjet recording method having high productivity using the ink set and a printed material recorded by the inkjet recording method. BRIEF DESCRIPTION OF DRAWINGS FIG. 1: A schematic diagram showing a sectional view when an image layer and a clear ink layer are formed above a recording medium using the ink set of the present invention. FIG. 2: An external perspective view showing one example of ink jet recording equipment suitably used in the present invention. FIG. 3: A transparent plan view schematically showing a paper transport path of the ink jet recording equipment shown in FIG. 2. FIG. 4: A transparent plan view showing the layout configuration of an ink jet head and a UV irradiation section shown in FIG. 2. FIG. 5: A perspective view showing an example of the configuration of a light source movement part for moving the UV irradiation section shown in FIG. 4. FIG. 6: An explanatory view showing an example of the configuration of the ink jet head and the UV irradiation section for forming an image shown in FIG. 1. FIG. 7: A transparent side view showing an example of the configuration of a provisional curing light source unit used as a provisional curing light source of the present embodiment. FIG. 8: A transparent plan view of the provisional curing light source unit shown in FIG. 7. FIG. 9: A block diagram showing the configuration of an ink supply system of the ink jet recording equipment. FIG. 10: A block diagram showing the configuration of the ink jet recording equipment. DESCRIPTION OF EMBODIMENTS The actinic radiation-curing type ink set of the present invention (hereinafter, also called simply an 'ink set') comprises a colored ink composition and a clear ink composition (C1), the colored ink composition comprising (Component D) a colorant, (Component A1) a radically polymerizable compound, and (Component B1) a polymerization initiator, and the clear ink composition (C1) comprising (Component S) an organic solvent, (Component A2) a radically polymerizable compound, and (Component B2) a polymerization initiator. In the present invention, the notation 'X to Y', which expresses a numeral range, has the same meaning as 'at least X but no greater than Y'. Furthermore, '(Component S) an organic solvent', etc. are also simply called 'Component S', etc. Moreover, when both or either of 'acrylate' and 'methacrylate' are referred to, it might be expressed as '(meth)acrylate'. Furthermore, 'a clear ink composition', etc. are also simply called 'a clear ink' etc. A clear ink composition (C1) and a clear ink composition (C2) are collectively referred to as 'a clear ink composition' or 'a clear ink'. Furthermore, 'mass%' and 'parts by mass' have the same meanings as 'wt%' and 'parts by weight' respectively. Moreover, in the present invention a combination of the preferred embodiments explained below is a more preferred embodiment. The present invention is explained in detail below. I. Actinic radiation-curing type ink set. The actinic radiation-curing type ink set of the present invention comprises an ink composition which is curable upon exposure to actinic radiation. The 'actinic radiation1 referred to in the present invention is radiation that can provide energy that enables an initiating species to be generated in the ink when irradiated, includes a rays, y rays, X rays, ultraviolet rays, visible light, and an electron beam. Among these, ultraviolet rays and an electron beam are preferable from the viewpoint of curing sensitivity and the availability of equipment, and ultraviolet rays are more preferable. The actinic radiation-curing type ink set of the present invention is preferably an ink set for multiple layer formation, and the ink set for multiple layer formation preferably forms an image layer by means of a colored ink composition group comprising a yellow ink composition, a magenta ink composition, a cyan ink composition, and a black ink composition and forms a clear ink layer by means of a clear ink composition. Furthermore, the actinic radiation-curing type ink set of the present invention comprises a clear ink composition (C1) comprising an organic solvent and, furthermore, preferably comprises a clear ink composition (C2) that does not comprise an organic solvent. The clear ink (C2) not comprising an organic solvent means that it comprises substantially no organic solvent, and means that the organic solvent including moisture contained in a normal state (25°C 1 atm) is no greater than 1.0 mass% relative to the total amount of the clear ink composition. It is preferable for the colored ink composition not to comprise an organic solvent or to have an organic solvent content of no greater than 1.0 mass% relative to the total amount of the colored ink composition. One example of a mode in which an image layer and a clear ink layer are formed above a recording medium using the actinic radiation-curing type ink set of the present invention is explained below by reference to a drawing. FIG. 1 is a schematic diagram showing a sectional view when an image layer 14 and a clear ink layer 16 are formed above a recording medium (support or substrate) 12 using the actinic radiation-curing type ink set of the present invention. Furthermore, the arrow V in the diagram shows the direction from which the image is viewed (observation direction). In FIG. 1, when the recording medium 12 is transparent, after a white layer 18 is formed above the recording medium 12, the image layer 14 may be formed there above. When the recording medium 12 is reflective, such as when it is paper, the white layer 18 is unnecessary. In the present invention, the recording medium 12 is preferably light-reflecting, and examples thereof include paper, synthetic paper, and tarpaulin (PVC), which are described later for the recording medium. In addition, the clear ink layer is provided in a region where at least an image has been formed, and it is preferably provided as a substantially uniform layer in a region where an image has been formed or a region wider than it. In the clear ink layer, the clear ink (C1) is preferably used in a high surface gloss (gloss) mode of a high image quality mode of an inkjet printer, and the clear ink (C2) is preferably used in a low surface gloss (matte) mode of the printer. The present invention is not limited to the mode in which two layers are formed; examples thereof include a mode in which three layers, that is, the white layer 18, the image layer 14, and the clear ink layer (C1 or C2) 16 are provided in that order above the recording medium 12 and a mode in which a multi-layer structure is formed by providing above a reflective recording medium 12 a plurality of the image layers 14 and the clear ink layer 16 in that order. The clear layer may have a multi-layer structure, and the clear layer may be overlaid above the whole of the image layer or the whole of a non-image area and a specific image area. Furthermore, only one of a high surface gloss (gloss) part and a low surface gloss (matte) part may be formed or they may be formed simultaneously, and a mode in which a gloss part is formed in an area that is desired to have high surface gloss and a matte part is formed in an area that is desired to have low surface gloss is also preferable. Although details of the mechanism of action for the exhibition of the effects of the present invention are unclear, it is surmised to be as follows. When carrying out inkjet printing using a clear ink composition, there is a case in which the actual amount of the clear ink composition discharged is smaller than the amount of ink that is required to be discharged as determined from the maximum liquid droplet volume of the inkjet printer head, the head nozzle resolution, the ink discharge frequency, and the productivity (transport speed of recording medium). In this case, since the amount of ink of the landed clear ink composition necessary for spreading while wet has not been fully discharged, it is thought that crater-shaped recesses (orange-like craters) are formed within an image. When a printer is made to have high productivity, a lot of the performance is achieved by increasing the speed of transport of a carriage, which includes an inkjet head. However, because of this, the actual amount of clear ink discharged is smaller than the amount of clear ink that is required to be discharged in order to obtain high surface gloss, and the above-mentioned defect is a problem in achieving high productivity. In this way, it is thought that when high productivity is sought, the spreading while wet of the clear ink composition becomes insufficient, the surface state of a printed image becomes poor, and the surface gloss becomes insufficient. Furthermore, when printing in high image quality mode, since the time from discharge onto a recording medium to exposure is long, oxygen dissolves in a landed ink liquid droplet, the polymerizability of the surface of the ink liquid droplet is degraded, and there is the problem that sand-ripple-like lines (swath lines) are formed on a printed image surface. In the present invention, it is surmised that, due to use of the clear ink composition comprising an organic solvent, the clear ink layer undergoes appropriate spreading while wet, thus improving the surface gloss of a printed image. Furthermore, it is surmised that due to the clear ink layer decreasing in film thickness due to evaporation of the organic solvent after being discharged, the curability of the clear layer improves and the blocking resistance improves. Moreover, it is surmised that, although the mechanism of action is unclear, due to the film thickness of the clear layer being decreased, the stretchability improves. In one embodiment, shown in FIG. 1, the image layer is a lower layer, a clear ink layer comprising an organic solvent and having good spreading while wet and excellent curability is formed above the image layer, and it is surmised that this clear ink layer suppresses degradation of the polymerizability of the surface of the image layer, which is a lower layer, caused by oxygen dissolving therein, thus improving the curability. In accordance with the ink set of the present invention, when forming two layers as above, an image having excellent adhesion between substrate and ink and between ink and ink and also having excellent image quality, surface gloss, and surface state is obtained. (Ink composition) The colored ink composition and the clear ink composition of the actinic radiation-curing type ink set of the present invention are now explained. In the present invention, when referring simply to an 'ink composition', it means 'a collective term for the colored ink composition and the clear ink composition'. The colored ink composition is also called simply a 'colored ink' or a 'color ink'. When a 'clear ink composition' is referred to, it means 'a collective term for the clear ink composition (C1) and the clear ink composition (C2)', and the 'clear ink composition (C1)' and the 'clear ink composition (C2)' are also simply called a 'clear ink C1' and a 'clear ink C2'. The colored ink composition is an ink composition, other than the clear ink, having a color, and examples thereof include a black ink, a cyan ink, a magenta ink, and a yellow ink. The ink set of the present invention comprises at least one type of colored ink composition as the colored ink composition, and when it comprises a plurality of colored ink compositions, it is preferable that at least one type of colored ink satisfies requirements described in <4>, <5>, <7>, <14>, <15>, etc. above, and it is more preferable that all of the colored ink compositions satisfy them. The ink composition used in the present invention is preferably an oil-based ink composition that can be cured by actinic radiation. The actinic radiation is, as described above, preferably UV or an electron beam from the viewpoint of curing sensitivity and the ready availability of equipment, and is particularly preferably UV. Components of the ink compositions forming the actinic radiation-curing type ink set of the present invention are explained below. (Component S) Organic solvent The clear ink composition (C1) used in the actinic radiation-curing type ink set of the present invention comprises (Component S) an organic solvent. The organic solvent referred to in the present invention means a solvent that contains a carbon atom and is a liquid at 25°C, and is preferably a water-soluble organic solvent. The water-soluble organic solvent referred to here means an organic solvent that has a solubility in 100 parts by mass of water at 25°C of at least 10 parts by mass. As the water-soluble organic solvent that can be used in the present invention, at least one type of organic solvent selected from the group consisting of an alcohol, a polyhydric alcohol, a polyhydric alcohol ether, a nitrogen-containing compound, and a sulfur-containing compound is preferable, at least one type of organic solvent selected from the group consisting of an alcohol, a polyhydric alcohol, and a polyhydric alcohol ether is more preferable, and at least one type of organic solvent selected from the group consisting of an alcohol and a polyhydric alcool ether is yet more preferable. Specific examples of the water-soluble organic solvent that can be used in the present invention include those below. Examples of the alcohol include a monohydric straight-chain or branched aliphatic alcohol having 1 to 20 carbons and a monohydric aliphatic cyclic alcohol having 4 to 20 carbons. Preferred examples of the alcohol include a monohydric straight-chain or branched aliphatic alcohol having 1 to 6 carbons, and a monohydric aliphatic cyclic alcohol having 5 to 8 carbons. Preferred examples thereof include methanol, ethanol, propanol, isopropanol, 1-butyl alcohol, isobutanol, secondary butanol, tertiary butanol, pentanol, hexanol, cyclohexanol, and benzyl alcohol. Examples of the polyhydric alcohol include a di- or higher-hydric straight-chain or branched aliphatic alcohol having 2 to 20 carbons, preferably 2 to 8 carbons, and more preferably 2 to 6 carbons, and a di- or higher-hydric aliphatic cyclic alcohol having 4 to 20 carbons, and preferably 5 to 8 carbons. The number of hydroxy groups per molecule is preferably 2 to 6, more preferably 2 to 4, and yet more preferably 2 or 3. Furthermore, the polyhydric alcohol preferably contains at least one alkyleneoxy group having 2 to 6 carbons in the hydrocarbon chain. Among them, a dihydric straight-chain or branched aliphatic alcohol having 2 to 8 carbons is preferable, and a dihydric straight-chain or branched aliphatic alcohol having 2 to 6 carbons is more preferable. The dihydric straight-chain or branched aliphatic alcohol may have an ether bond in the molecule. Preferred examples thereof include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerol, hexanetriol, thiodiglycol, and 2-methylpropanediol. Examples of the polyhydric alcohol ether include an ether in which the hydrogen atom of a hydroxy group of a di- or higher-hydric straight-chain or branched aliphatic alcohol having 2 to 20 carbons, preferably 2 to 9 carbons, and more preferably 2 to 6 carbons is replaced by an aliphatic hydrocarbon group having 1 to 10 carbons, and preferably 2 to 4 carbons or an aromatic hydrocarbon group having 6 to 12 carbons and an ether in which the hydrogen atom of a hydroxy group of a di- or higher-hydric aliphatic cyclic alcohol having 4 to 20 carbons, and preferably 5 to 8 carbons is replaced by an aliphatic hydrocarbon group having 1 to 10 carbons, and preferably 1 to 4 carbons or an aromatic hydrocarbon group having 6 to 12 carbons. Furthermore, the polyhydric alcohol ether may contain as an ether bond at least one alkyleneoxy group having 2 to 6 carbons in the hydrocarbon chain in addition to the ether bond formed by etherification of the hydroxy group of the polyhydric alcohol. The polyhydric alcohol ether is preferably a monoether of dihydric alcohol. Preferred examples thereof include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mononormal butyl ether, ethylene glycol monotertiary butyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, 1-ethoxy-2-propanol, propylene glycol monobutyl ether, tripropylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, ethylene glycol monophenyl ether, and propylene glycol monophenyl ether. Examples of the nitrogen-containing compound include an amine, an amide, and a nitrogen-containing heterocyclic compound. Examples of the amine include a primary to tertiary monoamine substituted with an aliphatic hydrocarbon group having 1 to 10 carbons, an aliphatic cyclic amine having 1 to 10 carbons, and a polyamine having 2 to 20 carbons. Preferred examples thereof include ethanolamine, diethanolamine, triethanolamine, A/-methyldiethanolamine, A/-ethyldiethanolamine, morpholine, yV-ethylmorpholine, ethylenediamine, diethylenediamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, and tetramethylpropylenediamine. Examples of the amide include an amide having 1 to 10 carbons. Preferred examples thereof include formamide, A/,A/-dimethylformamide, and A/./V-dimethylacetamide. Examples of the nitrogen-containing heterocyclic compound include a nitrogen-containing cyclic compound having 4 to 20 carbons, which may contain an oxygen atom, a sulfur atom, etc. in the molecule in addition to a nitrogen atom. Preferred examples thereof include 2-pyrrolidone, A/-methyl-2-pyrrolidone, cyclohexylpyrrolidone, 2-oxazolidone, and 1,3-dimethyl-2-imidazolidinone. Examples of other nitrogen-containing compounds include urea and acetonitrile. Furthermore, in addition thereto, as an oxygen-containing heterocyclic compound, y-butyrolactone can be cited, and as the sulfur-containing compound a sulfoxide (e.g. dimethyl sulfoxide, etc.) and a sulfone (e.g. sulfolane, etc.) can be cited. Among them, Component S is preferably at least one type of organic solvent selected from the group consisting of a monohydric straight-chain or branched aliphatic alcohol having 1 to 6 carbons, a monohydric aliphatic cyclic alcohol having 5 to 8 carbons, and monoalkyl ether (alkyl group having 1 to 4 carbons) of dihydric straight-chain or branched aliphatic alcohol having 2to 9 carbons. Among them, Component S is preferably methanol, isopropyl alcohol, 1-butyl alcohol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, 1-ethoxy-2-propanol, ethylene glycol monoethyl ether, ethylene glycol mononormal butyl ether, ethylene glycol monotertiary butyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, 2-pyrrolidone, or A/-methyl-2-pyrrolidone, more preferably methanol, isopropyl alcohol, 1-butyl alcohol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, 1-ethoxy-2-propanol, ethylene glycol monoethyl ether, ethylene glycol mononormal butyl ether, ethylene glycol monotertiary butyl ether, ethylene glycol monomethyl ether acetate, or ethylene glycol monoethyl ether acetate, and yet more preferably methanol, isopropyl alcohol, 1-butyl alcohol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, or 1-ethoxy-2-propanol, particularly preferably isopropaol or 1-butyl alcohol, and most preferably isopropaol. The boiling point of Component S is preferably 65°C to 250°C, more preferably 65°C to 230°C, yet more preferably 70°C to 140°C, and particularly preferably 80°C to 120°C. It is preferable for the boiling point to be in the above range since a printed material having excellent surface gloss and excellent blocking resistance is obtained. Component S is particularly preferably the monohydric alcohol, the polyhydric alcohol and the polyhydric alcohol ether having the above-mentioned boiling point. Component S may be used singly or in a combination of a plurality thereof. The content of Component S is preferably 1 to 80 mass% relative to the total amount of the clear ink composition (C1), more preferably 5 to 70 mass%, yet more preferably 10 to 60 mass%, and particularly preferably more than 20 mass% but no greater than 40 mass%. The clear ink composition (C1) comprising Component S is an oil-based ink composition and preferably contains no more water as a solvent than an amount that is the moisture content of Component S in a normal state. The content of water in the clear ink C1 is preferably no greater than 1 mass% relative to the total mass of the ink composition. (Component A1), (Component A2), and (Component A3) Radically polymerizable compounds. In the ink composition used in the present invention, the colored ink composition comprises (Component A1) a radically polymerizable compound and the clear ink composition (C1) comprises (Component A2) a radically polymerizable compound. Furthermore, the clear ink composition (C2) preferably comprises (Component A3) a radically polymerizable compound. In the present invention, the radically polymerizable compounds of Component A1 to Component A3 are not particularly limited as long as they are compounds that undergo a polymerization reaction caused by a radical generated by decomposition of a radical polymerization initiator contained in the ink composition used in the present invention when irradiated with actinic radiation, and known radically polymerizable compounds may be used. In the present invention, the colored ink composition preferably comprises as Component A1 (Component A1-1) an A/-vinyl compound and/or (Component A1-2) a compound represented by Formula (a-2). Component A1-1 and Component A1-2 are explained below. (Component A1-1) A/-vinyl compound The colored ink composition used in the present invention preferably comprises (Component A1-1) an W-vinyl compound as (Component A1) the radically polymerizable compound. In addition, one in which the clear ink comprises Component A1-1 is not excluded. As the A/-vinyl compound, an A/-vinyllactam is preferable and a compound represented by Formula (a-1) is more preferable. In Formula (a-1), n denotes an integer of 1 to 5; n is preferably an integer of 2 to 4 from the viewpoint of flexibility after the ink composition is cured, adhesion to a recording medium, and ease of availability of starting material, n is more preferably an integer of 2 or 4, and n is particularly preferably 4, which is /V-vinylcaprolactam. /V-vinylcaprolactam is preferable since it has excellent safety, is commonly used and easily available at a relatively low price, and gives particularly good ink curability and adhesion of a cured film to a recording medium. The content of Component A1-1 in the colored ink composition used in the present invention is preferably in the range of 5 to 60 mass% relative to the mass of the entire colored ink composition, more preferably in the range of 15 to 35 mass%. When the content is 5 mass% or greater the adhesion to a recording medium is excellent, and when the content is no greater than 60 mass% the storage stability is excellent. (Component A1-2) Compound represented by Formula (a-2) The colored ink composition used in the present invention preferably comprises (Component A1-2) a compound represented by Formula (a-2) as (Component A1) the radically polymerizable compound. In addition, one in which the clear ink comprises Component A1-2 is not excluded. It is surmised that the compound represented by Formula (a-2) has a low surface tension and improves spreading while wet of the ink composition. Furthermore, it has appropriate polarity, is resistant to incomplete surface curing, and can give a cured material (image layer and clear ink layer) having excellent adhesion. (In (a-2), R1, R2, and R3 independently denote a hydrogen atom, a methyl group, or an ethyl group, and X2 denotes a single bond or a divalent linking group.) R1 is preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom. R2 and R3 are independently preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom, and it is yet more preferable that both R2 and R3 are hydrogen atoms. The divalent linking group denoted by X2 is not particularly limited as long as the effects of the present invention are not greatly impaired, and is preferably a divalent hydrocarbon group or a divalent group in which a hydrocarbon group and an ether bond are combined, and more preferably a divalent hydrocarbon group, poly(alkyleneoxy) group, or poly(alkyleneoxy)alkyl group. Furthermore, the number of carbons of the divalent linking group is preferably 1 to 60, and more preferably 1 to 20. X2 is preferably a single bond, a divalent hydrocarbon group, or a divalent group in which a hydrocarbon group and an ether bond are combined, more preferably a divalent hydrocarbon group having 1 to 20 carbons, yet more preferably a divalent hydrocarbon group having 1 to 8 carbons, and particularly preferably a methylene group. Specific examples of Component A1-2 are cited below, but it is not limited to these compounds. In the specific examples below, R denotes a hydrogen atom or a methyl group. Among them, cyclic trimethylolpropane formal (meth)acrylate is preferable, and cyclic trimethylolpropane formal acrylate (CTFA) is particularly preferable. Component A1-2 may be a commercial product, and specific examples of the commercial product include SR531 (SARTOMER). From the viewpoint of curability of the colored ink composition and adhesion between a recording medium and an image, the content of Component A1-2 is preferably 1 to 65 mass% relative to the entire mass of the colored ink composition, more preferably 3 to 60 mass%, and yet more preferably 5 to 60 mass%, and most preferably 5 to 40 mass%. (Component A-3) Trimethylolpropane triacrylate In the present invention, the ink composition (the colored ink composition and the clear ink composition) preferably comprises (Component A-3) trimethylolpropane triacrylate as (Component A1) to (Component A3) the radically polymerizable compound. It is preferable for Component A-3 to be contained since a balance can be achieved between curability and wind-up suitability (flexibility) of an output sample of a roll substrate. From the viewpoint of a balance being achieved between the curability and the wind-up suitability (flexibility) of an output sample of a roll substrate, the content of Component A-3 is preferably 0.1 to 10 mass% relative to the total mass of the ink composition. (Component A-4) Other monofunctional (meth)acrylate The ink composition used in the present invention may comprise (Component A-4) a monofunctional (meth)acrylate other than Component A1-2. From the viewpoint of inkjet discharge properties and flexibility, the content of Component A-4 is preferably 1 to 50 mass% relative to the total mass of the ink composition, more preferably 3 to 45 mass%, and yet more preferably 5 to 40 mass%. Specific examples of the other monofunctional (meth)acrylate compound include 2-phenoxyethyl (meth)acrylate, benzyl (meth)acrylate, isoamyl (meth)acrylate, stearyl (meth)acrylate, lauryl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, decyl (meth)acrylate, isomyristic (meth)acrylate, isostearyl (meth)acrylate, 2-ethylhexyl diglycol (meth)acrylate, 2-hydroxybutyl (meth)acrylate, buthoxyethyl (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypropylene glycol (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-(meth)acryloyloxyethylsuccinic acid, 2-(meth)acryloyloxyethyl-2-hydroxyethylphthalic acid, a lactone-modified flexible (meth)acrylate, f-butylcyclohexyl (meth)acrylate, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, cyclopentenyl (meth)acrylate, cyclopentenyloxyethyl (meth)acrylate, and dicyclopentanyl (meth)acrylate, etc. The monofunctional (meth)acrylate contained in the colored ink composition is preferably a compound represented by Formula (a-2), and the monofunctional (meth)acrylate contained in the clear ink composition is preferably isobornyl (meth)acrylate, cyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, or f-butylcyclohexyl acrylate. In the present invention, the total content of monofunctional radically polymerizable compounds of the colored ink composition, including Component A1-1 and Component A1-2, is preferably 60 to 100 mass% relative to the total amount of (Component A1) the radically polymerizable compound. When the content of the monofunctional radically polymerizable compounds is in the above-mentioned range, an image having excellent ink -ink and ink-recording medium adhesion and excellent flexibility can be obtained. The content of the monofunctional polymerizable compounds of the each of colored ink compositions is preferably 70 to 100 mass% relative to the total amount of Component A1, and more preferably 75 to 95 mass%. In addition, the monofunctional polymerizable compound includes a monofunctional polymerizable compound such as (Component A-4) another monofunctional (meth)acrylate. Furthermore, the clear ink composition (C1) preferably has a total content of the monofunctional radically polymerizable compound of 0 to 30 mass% relative to the total amount of the radically polymerizable compound (Component A2), more preferably 0 to 25 mass%, and yet more preferably 0 to 20 mass%. Moreover, the clear ink composition (C2) has a total content of the monofunctional radically polymerizable compound of 0 to 30 mass% relative to the total amount of the radically polymerizable compound (Component A3), more preferably 0 to 25 mass%, and yet more preferably 0 to 20 mass%. When the content of the monofunctional radically polymerizable compound in the clear ink composition is in the above ranges, the curability and blocking resistance are excellent. (Component A-5) Other polyfunctional (meth)acrylate The ink composition used in the present invention may comprise (Component A-5) other polyfunctional (meth)acrylate other than Component A-3 above. Due to the ink composition comprising a polyfunctional (meth)acrylate compound, high curability can be obtained. Specific examples of Component A-5 include bis(4- (meth)acryloxypolyethoxyphenyl)propane, neopentyl glycol di(meth)acrylate, ethoxylated (2) neopentyl glycol di(meth)acrylate (compound formed by di(meth)acrylating neopentyl glycol ethylene oxide 2 mol adduct), propoxylated (2) neopentyl glycol di(meth)acrylate (compound formed by di(meth)acrylating neopentyl glycol propylene oxide 2 mol adduct), ethoxylated (3) trimethylol propane tri(meth)acrylate (compound formed by tri(meth)acrylating trimethylol propane ethylene oxide 3 mol adduct), 1,6- hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, ethylene glycol di(meth)acryiate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, tricyclodecanedimethanol di(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, dimethyloltricyclodecane di(meth)acrylate, modified glycerol tri(meth)acrylate, modified bisphenol A di(meth)acrylate, bisphenol A propylene oxide (PO) adduct di(meth)acrylate, bisphenol A ethylene oxide (EO) adduct di(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and caprolactone-modified dipentaerythritol hexa(meth)acrylate. The colored ink composition preferably comprises as Component A-5 1,6-hexanediol diacrylate or ethoxylated (3) trimethylolpropane triacrylate. Furthermore, the clear ink composition preferably comprises as Component A-5 dipropylene glycol diacrylate, tricyclodecanedimethanol diacrylate, or propoxylated (2) neopentyl glycol diacrylate (a compound in which the 2 mole propylene oxide adduct of neopentyl glycol is diacrylated). Examples of preferred combinations of polyfunctional (meth)acrylates in the colored ink composition include a combination of trimethylolpropane triacrylate (Component A-3) and 1,6-hexanediol diacrylate and a combination of ethoxylated (3) trimethylolpropane triacrylate and 1,6-hexanediol diacrylate. Examples of preferred combinations of polyfunctional (meth)acrylates in the clear ink composition include a combination of dipropylene glycol diacrylate and tricyclodecanedimethanol diacrylate and a combination of dipropylene glycol diacrylate, tricyclodecanedimethanol diacrylate, and propoxylated (2) neopentyl glycol diacrylate. The ink composition used in the present invention may comprise an oligomer as the polyfunctional (meth)acrylate compound. The 'oligomer' means a polymer having a limited number (preferably 5 to 100) of monomer-based constituent units. A weight-average molecular weight of the oligomer is preferably 400 to 10,000, and more preferably 500 to 5,000. The oligomer is preferably a compound having a (meth)acryloyl group as a functional group. From the viewpoint of a balance between flexibility and curability, it is preferable for the number of the functional group contained in the oligomer to be 2 to 15 per oligomer molecule, more preferably 2 to 6, yet more preferably 2 to 4, and particularly preferably 2. Examples of the oligomer in the present invention include a polyester (meth)acrylate-based oligomer, an olefin-based oligomer (an ethylene oligomer, a propylene oligomer, a butene oligomer, etc.), a vinyl-based oligomer (a styrene oligomer, a vinyl alcohol oligomer, a vinylpyrrolidone oligomer, a (meth)acrylate oligomer, etc.), a diene-based oligomer (a butadiene oligomer, a chloroprene rubber, a pentadiene oligomer, etc.), a ring-opening polymerization type oligomer (di-, tri-, tetra-ethylene glycol, polyethylene glycol, polyethylimine, etc.), an addition-polymerization type oligomer (an oligoester (meth)acrylate, a polyamide oligomer, a polyisocyanate oligomer), an addition-condensation oligomer (a phenolic resin, an amino resin, a xylene resin, a ketone resin, etc.), and amine-modified polyester oligomer, etc. Among these, an oligoester (meth)acrylate are preferable, and among them a urethane (meth)acrylate and a polyester (meth)acrylate are more preferable, and a urethane (meth)acrylate is particularly preferable because the ink composition provides excellent curability and adhesion. With regard to the oligomer, one type thereof may be used on its own or two or more types may be used in combination. As the urethane (meth)acrylate, an aliphatic urethane (meth)acrylate and an aromatic urethane (meth)acrylate may preferably be cited. With respect to the oligomer, "Origomar Handobukku (Oligomer Handbook)1 (edited by Junji Furukawa, The Chemical Daily Co., Ltd.) may also be referred to. Examples of the oligomer based on the urethane (meth)acrylate include U-2PPA, U-4HA, U-6HA, U-6LPA, U-15HA, U-324A, UA-122P, UA5201, UA-512, etc. manufactured by Shin-Nakamura Chemical Co., Ltd.; CN964A85, CN964, CN959, CN962, CN963J85, CN965, CN982B88, CN981, CN983, CN996, CN9002, CN9007, CN9009, CN9010, CN9011, CN9178, CN9788, CN9893 manufactured by Sartomer; EB204, EB230, EB244, EB245, EB270, EB284, EB285, EB810, EB4830, EB4835, EB4858, EB1290, EB210, EB215, EB4827, EB4830, EB4849, EB6700, EB204, EB8402, EB8804, EB8800-20R, etc. manufactured by DAICEL-CYTEC COMPANY LTD. Examples of the amine-modified polyester oligomer include EB524, EB80, EB81 manufactured by DAICEL-CYTEC COMPANY LTD.; CN550, CN501, CN551 manufactured by Sartomer; GENOMER5275 manufactured by RAHN AG. From the viewpoint of a balance being achieved between curability and adhesion, the content of the oligomer is preferably 0.3 to 10 mass% relative to the total mass of the ink composition, more preferably 0.5 to 8 mass%, and yet more preferably 0.5 to 7 mass%. In practice, the total content of the other polyfunctional (meth)acrylate (Component A-5) is adjusted from the viewpoint of viscosity increase when preparing an ink and improvement of curability. Because of this, the appropriate mass% depends on the viscosity of each ink, but it is preferably 0 to 30 mass% relative to the total mass of the colored ink composition, more preferably 0.5 to 25 mass%, yet more preferably 1 to 20 mass%, and particularly preferably 3 to 20 mass%. Furthermore, the total content of the other polyfunctional (meth)acrylate (Component A-5) is preferably 30 to 97 mass% relative to the total mass of the clear ink composition, more preferably 40 to 95 mass%, and yet more preferably 50 to 90 mass%. The total content of the polyfunctional radically polymerizable compound is preferably 0 to 30 mass% relative to the total mass of the colored ink composition, more preferably 1 to 25 mass%, yet more preferably 3 to 20 mass%, and particularly preferably 5 to 20 mass%. The total content of the polyfunctional radically polymerizable compound is preferably 30 to 97 mass% relative to the total mass of the clear ink composition, more preferably 40 to 95 mass%, yet more preferably 50 to 93 mass%, and particularly preferably 55 to 90 mass%. (Other radically polymerizable compound) In the present invention, the ink composition may comprise a vinyl ether compound as the other radically polymerizable compound. Vinyl ether compounds can be broadly divided into monovinyl ether compounds and di- or tri-vinyl ether compounds. The clear ink composition preferably comprises a vinyl ether compound, particularly preferably comprises a di- or tri-vinyl ether compound, and more preferably comprises a divinyl ether compound. Examples of vinyl ether compounds that are suitably used include di- or tri-vinyl ether compounds such as ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, and trimethylolpropane trivinyl ether, and monovinyl ether compounds such as ethylene glycol monovinyl ether, triethylene glycol monovinyl ether, hydroxyethyl monovinyl ether, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, hydroxynonyl monovinyl ether, cyclohexanedimethanol monovinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, isopropenyl vinyl ether, dodecyl vinyl ether, and diethylene glycol monovinyl ether. The total content of the radically polymerizable compound (Component A1) in the colored ink composition is preferably 65 to 99 mass% relative to the total mass of the colored ink composition, and more preferably 70 to 90 mass%. The total content of the radically polymerizable compound (Component A2) in the clear ink composition (C1) is preferably 20 to 90 mass% relative to the total mass of the clear ink composition (C1), more preferably 35 to 85 mass%, and yet more preferably 50 to 70 mass%. The total content of the radically polymerizable compound (Component A3) in the clear ink composition (C2) is preferably 65 to 99 mass% relative to the total mass of the clear ink composition (C2), and more preferably 70 to 90 mass%. (Component B1), (Component B2), and (Component B3) Polymerization initiators In the ink composition used in the present invention, the colored ink composition comprises (Component B1) a polymerization initiator and the clear ink composition (C1) comprises (Component B2) a polymerization initiator. Furthermore, the clear ink composition (C2) preferably comprises (Component B3) a polymerization initiator. In the present invention, the polymerization initiator is preferably a radical polymerization initiator, and a known radical polymerization initiator may be used. With regard to the radical polymerization initiator that can be used in the present invention, a single type may be used or two or more types may be used in combination. Furthermore, the radical polymerization initiator may be used in combination with a cationic polymerization initiator. The radical polymerization initiator that can be used in the present invention is a compound that absorbs external energy to thus generate a polymerization initiating species. The external energy used in order to initiate polymerization is preferably actinic radiation, and a photopolymerization initiator is preferably used. Preferred examples of actinic radiation include an electron bean and UV as described above. Examples of the radical polymerization initiator that can be used in the present invention include (a) an aromatic ketone, (b) an acylphosphine compound, (c) an aromatic onium salt compound, (d) an organic peroxide, (e) a thio compound, (f) a hexaarylbiimidazole compound, (g) a ketoxime ester compound, (h) a borate compound, (i) an azinium compound, (j) a metallocene compound, (k) an active ester compound, (I) a compound having a carbon-halogen bond, (m) an alkylamine compound, etc. With regard to these radical polymerization initiators, the above-mentioned compounds (a) to (m) may be used singly or in combination In the present invention, as (Component B1) to (Component B3) the polymerization initiator, (Component B-1) a bisacylphosphine compound and (Component B-2) a monoacylphosphine compound are preferable. Hereinafter, (Component B-1) a bisacylphosphine compound, (Component B-2) a monoacylphosphine compound, and other polymerization initiator are explained. (Component B-1) Bisacylphosphine compound In the present invention, (Component B-1) a bisacylphosphine compound can preferably be cited as the radical polymerization initiator (Component B1) to (Component B3). Preferred examples of Component B-1 and Component B-2, which is described later, include bisacylphosphine oxide compounds and monoacylphosphine compounds described in paragraphs 0080 to 0098 of JP-A-2009-096985. Component B-1 preferably has a partial structure represented by Formula (b-1-1) in the structure of the compound, n (In Formula (b-1-1), denotes a bonding position.) Component B-1 is particularly preferably a compound represented by Formula (b-1-2). (In Formula (b-1-2), R9, R10 and R11 independently denote an aromatic hydrocarbon group, which may have a methyl group or an ethyl group as a substituent.) With regard to a bisacylphosphine oxide compound represented by Formula (b-1-2), it is preferable that R9 to R11 are phenyl groups, which may have a methyl group as a substituent, and it is more preferable that R11 is a phenyl group and R9 and R10 are phenyl groups having 1 to 3 methyl groups. Among them, as the bisacylphosphine oxide compound represented by Formula (b-1-2), bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (IRGACURE 819, manufactured by Ciba Japapn) is preferable. (Component B-2) Monoacylphosphine compound In the present invention, (Component B-2) a monoacylphosphine compound can preferably be cited as the radical polymerization initiator (Component B). Component B-2 preferably has a partial structure represented by Formula (b-2-1) in the structure of the compound, n (In Formula (b-2-1), denotes a bonding position.) Component B-2 is particularly preferably a compound represented by Formula (b-2-2). (In Formula (b-2-2), R6, R7, and R8 independently denote an aromatic hydrocarbon group, which may have a methyl group or an ethyl group as a substituent.) With regard to a monoacylphosphine oxide compound represented by Formula (b-2-2), it is preferable that R6 to R8 are phenyl groups, which may have a methyl group as a substituent, and it is more preferable that R7 and R8 are phenyl groups and R6 is a phenyl group having 1 to 3 methyl groups. Among them, as the monoacylphosphine oxide compound represented by Formula (b-2-2), 2,4,6-trimethylbenzoyldiphenylphosphine oxide (Darocur TPO manufactured by Ciba Japan, Lucirin TPO manufactured by BASF) is preferable. In the present invention, the colored ink composition preferably comprises a bisacylphosphine oxide compound (Component B-1) and/or a monoacylphosphine oxide compound (Component B-2). Furthermore, the colored ink composition preferably comprises at least a bisacylphosphine oxide compound (Component B-1) as Component B. It is preferable for the colored ink composition to comprise Component B-1 since the excellent curability can be obtained even if a small amount is added. In addition, compared with a monoacylphosphine oxide compound, a bisacylphosphine oxide compound can improve ink sensitivity with a low amount thereof added, but from the viewpoint of a printed material being colored yellow it is not suitable for a clear ink. Because of this, for an ink having high saturation such as a clear ink or a white ink, it is not desirable to add a bisacylphosphine oxide compound from the viewpoint of yellow coloration. On the other hand, in a color ink for which yellowing of an image is not conspicuous a bisacylphosphine oxide compound can be added from the viewpoint of ensuring sensitivity, but if the amount thereof added is large since there is the possibility of yellow coloration, it cannot be used on its own. It is therefore preferable to use it in combination with a monoacylphosphine oxide compound, which is a high sensitivity initiator causing less yellow coloration than a bisacylphosphine oxide compound. In the colored ink composition, when the total amount of radical polymerization initiator is 100 parts by mass, the total amount of Component B-1 and Component B-2 is preferably at least 20 parts by mass, more preferably at least 25 parts by mass, and yet more preferably at least 30 parts by mass. The total content of Component B-1 and Component B-2 in the colored ink composition is preferably 0.1 to 20 mass% relative to the total mass of the colored ink composition, and more preferably 1 to 15 mass%. Furthermore, in the present invention, the clear ink composition (C1) and the clear ink composition (C2) preferably comprise a monoacylphosphine oxide compound (Component B-2) as Component B2 and Component B3. It is preferable for the clear ink composition to comprise Component B-2 as Component B2 and Component B3 since yellowing of the image is suppressed and excellent curability is obtained. In the clear ink composition, when the total amount of radical polymerization initiator is 100 parts by mass, it is preferable for it to comprise at least 50 parts by mass of the monoacylphosphine oxide compound, more preferably 60 to 100 parts by mass, yet more preferably 70 to 100 parts by mass, and particularly preferably substantially 100 parts by mass. The content of Component B-2 of the clear ink composition (C1) is preferably 1 to 20 mass% relative to the total mass of the clear ink composition (C1), and more preferably 5 to 15 mass%. The content of Component B-2 of the clear ink composition (C2) is preferably 5 to 25 mass% relative to the total mass of the ink composition (C2), and more preferably 10 to 20 mass%. (Component B-3) Thioxanthone compound and/or thiochromanone compound The ink composition used in the present invention preferably comprises (Component B-3) a thioxanthone compound and/or a thiochromanone compound. In particular, from the viewpoint of curability, the colored ink composition and the clear ink composition preferably comprise Component B-3. In the colored ink composition, the amount of Component B-3 is preferably 10 to 50 parts by mass when the total amount of the radical polymerization initiator is 100 parts by mass, and more preferably 20 to 40 parts by mass. The content of Component B-3 in the colored ink composition is preferably 0.1 to 10 mass% relative to the total mass of the colored ink composition, and more preferably 0.5 to 5 mass%. In the clear ink composition, the content of Component B-3 is preferably 0 to 1 parts by mass when the total amount of the radical polymerization initiator is 100 parts by mass, and more preferably 0 to 0.5 parts by mass. In the clear ink composition, the content of Component B-2 is preferably 0 to 5 mass% relative to the total mass of the clear ink composition, and more preferably 0.1 to 1 mass%. The thiochromanone compound is preferably a compound represented by Formula (b-3-2). R1 o 2 II R TV^-R6 o7 (b-3-2) R4 R In Formula (b-3-2), R1, R2, R3, R4, R5, R6, R7, and R8 independently denote a hydrogen atom, an alkyl group, a halogen atom, a hydroxy group, a cyano group, a nitro group, an amino group, an alkylthio group, an alkylamino group, an alkoxy group, an alkoxycarbonyl group, an acyloxy group, an acyl group, a carboxy group, or a sulfo group. The number of carbon atoms of an alkyl moiety of the alkyl group, alkylthio group, alkylamino group, alkoxy group, alkoxycarbonyl group, acyloxy group, and acyl group is preferably 1 to 20, more preferably 1 to 8, and yet more preferably 1 to 4. The acyloxy group may be an aryloxycarbonyl group, and the acyl group may be an arylcarbonyl group. In this case, the number of carbon atoms of an aryl moiety is preferably 6 to 14, and more preferably 6 to 10. Two of R1, R2, R3, and R4 that are adjacent may be bonded to each other, for example condensed, to form a ring. Examples of the ring structure when those above form a ring include a 5 or 6-membered aliphatic ring or aromatic ring; it may be a heterocyclic ring containing an element other than a carbon atom, and rings thus formed may be further combined to form a bicyclic ring, for example a condensed ring. These ring structures may further have a substituent. Examples of the substituent include those described for Formula (b-3-1). Examples of a heteroatom when the resulting ring structure is a heterocyclic ring include N, 0, and S. Furthermore, the thiochromanone compound is preferably a compound having on the thiochromanone ring structure at least one substituent (an alkyl group, a halogen atom, a hydroxy group, a cyano group, a nitro group, an amino group, an alkylthio group, an alkylamino group, an alkoxy group, an alkoxycarbonyl group, an acyloxy group, an acyl group, a carboxy group, or a sulfo group, etc.). As examples of the substituent above, an alkyl group, a halogen atom, a hydroxy group, an alkylthio group, an alkylamino group, an alkoxy group and an acyloxy group are preferable, an alkyl group having 1 to 20 carbons and a halogen atom are more preferable, and an alkyl group having 1 to 4 carbons and a halogen atom are yet more preferable. Furthermore, the thiochromanone compound is more preferably a compound having at least one substituent on an aromatic ring and at least one substituent on a thiocyclohexenone ring. The specific examples of the thiochromanone compound preferably include (1-1) to (1-31) listed below. Among them, (1-14), (1-17) and (1-19) are more preferable, and (1-14) is particularly preferable. O n «.. r\ r\ n ri The ink composition used in the present invention may comprise a polymerization initiator other than Component B-1 to Component B-3. The other polymerization initiator is preferably (Component B-4) an a-aminoalkylphenone compound. (Component B-4) a-Aminoalkylphenone compound The ink composition used in the present invention may comprise (Component B-4) an a-aminoalkylphenone compound. The colored ink composition preferably comprises Component B-4. Component B-4 is preferably a compound represented by Formula (b-4-1). In Formula (b-4-1), R1, R2, and R3 independently denote a hydroxy group, an optionally substituted alkyl group, an optionally substituted alkoxy group, or an optionally substituted amino group, and X denotes a hydrogen atom, an optionally substituted amino group, an optionally substituted alkylthio group, or an optionally substituted alkyl group. When R1, R2, R3, and X is an amino group, the substituents may be bonded to each other to form a heterocyclic group. Examples of the substituent include an alkyl group having 1 to 10 carbons. As Component B-4, a compound represented by Formula (b-4-2) or (b-4-3) is preferable. In Formula (b-4-2), R4, R5, R6, and R7 independently denote an optionally substituted alkyl group, and at least one of R4, R5 and R6, R7 may be bonded to each other to form a heterocyclic group. R1, R2, and the substituent have the same meanings as R1, R2, and the substituent in Formula (b-4-1). In Formula (b-4-3), RB denotes an optionally substituted alkyl group. R\ R2 and the substituent have the same meaning as R1, R2 and the substituent in Formula (b-4-1), and R4 and R5 have the same meaning as R4 and R5 in Formula (b-4-2). The heterocyclic group is not particularly limited and may be selected appropriately. For example, a morpholino group is preferable. Preferred examples of the a-aminoalkylphenone compound include a commercial product such as IRGACURE 369 and IRGACURE 907 manufactured by Ciba Japan. From the viewpoint of curability, the content of (Component B-4) the a-aminoalkylphenone compound is preferably 0.1 to 15 mass% relative to the ink composition, more preferably 0.5 to 10 mass%, and yet more preferably 1 to 5 mass%. Examples of the other polymerization initiator include aromatic ketones, aromatic onium salt compounds, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, and carbon halogen bond-containing compounds. Details of the above-mentioned polymerization initiators are known to a person skilled in the art, and are described in for example paragraphs 0090 to 0116 of JP-A-2009-185186. In the colored ink composition, the total amount of the radical polymerization initiator is preferably 0.5 to 30 mass% relative to the total mass of the ink composition, and more preferably 1 to 20 mass%. The total amount of the radical polymerization initiator in the clear ink composition (C1) is preferably 1 to 20 mass% relative to the total mass of the ink composition, and more preferably 5 to 15 mass%. The total amount of the radical polymerization initiator in the clear ink composition (C2) is preferably 5 to 25 mass% relative to the total mass of the ink composition, and more preferably 10 to 20 mass%. (Component D) Colorant The colored ink composition used in the present invention comprises (Component D) a colorant corresponding to each color. The clear ink comprises substantially no colorant, but a colorant may be used in some cases in order to improve a slight yellowing of the clear ink. In such cases, the content of the colorant in the clear ink is no greater than 1 mass%. The colorant that can be used in the present invention is not particularly limited, and various known pigments and dyes may be selected appropriately according to an intended application. Among them, as a colorant, a pigment is preferable particularly from the viewpoint of excellent light fastness. Pigments that are preferably used in the present invention are now described. With regard to the pigments, there is no particular limitation, and any generally commercially available organic pigment and inorganic pigment, resin particles dyed with a dye, etc. may be used. Furthermore, a commercial pigment dispersion or a surface-treated pigment such as, for example, a dispersion of a pigment in an insoluble resin, etc. as a dispersion medium or a pigment having a resin grafted on the surface, etc. may be used as long as the effects of the present invention are not impaired. Examples of these pigments include pigments described in, for example, 'Ganryo no Jiten (Pigment Dictionary)', Ed. by Seishiro Ito (2000), W. Herbst, K. Hunger, Industrial Organic Pigments, JP-A-2002-12607, JP-A-2002-188025, JP-A-2003-26978, and JP-A-2003-342503. Specific examples of the organic pigment and the inorganic pigment that can be used in the present invention include, as those exhibiting a yellow color, monoazo pigments such as C.I. Pigment Yellow 1 (Fast Yellow G, etc.) and C.I. Pigment Yellow 74, disazo pigments such as C.I. Pigment Yellow 12 (Disazo Yellow AAA, etc.) and C.I. Pigment Yellow 17, benzidine-free azo pigments such as C.I. Pigment Yellow 180, azo lake pigments such as C.I. Pigment Yellow 100 (Tartrazine Yellow Lake, etc.), condensed azo pigments such as C.I. Pigment Yellow 95 (Azo Condensation Yellow GR, etc.), acidic dye lake pigments such as C.I. Pigment Yellow 115 (Quinoline Yellow Lake, etc.), benzimidazolone pigments such as and C.I. Pigment Yellow 120 (Novoperm Yellow 2HG), basic dye lake pigments such as C.I. Pigment Yellow 18 (Thioflavine Lake, etc.), anthraquinone pigments such as Flavanthrone Yellow (Y-24), isoindolinone pigments such as Isoindolinone Yellow 3RLT (Y-110), quinophthalone pigments such as Quinophthalone Yellow (Y-138), isoindoline pigments such as Isoindoline Yellow (Y-139), nitroso pigments such as C.I. Pigment Yellow 153 (Nickel Nitroso Yellow, etc.), and metal complex azomethine pigments such as C.I. Pigment Yellow117 (Copper Azomethine Yellow, etc.). Examples of pigments exhibiting a red or magenta color include monoazo pigments such as C.I. Pigment Red 3 (Toluidine Red, etc.), disazo pigments such as C.I. Pigment Red 38 (Pyrazolone Red B, etc.), azo lake pigments such as C.I. Pigment Red 53:1 (Lake Red C, etc.) and C.I. Pigment Red 57:1 (Brilliant Carmine 6B), condensed azo pigments such as C.I. Pigment Red 144 (Azo Condensation Red BR, etc.), acidic dye lake pigments such as C.I. Pigment Red 174 (Phloxine B Lake, etc.), basic dye lake pigments such as C.I. Pigment Red 81 (Rhodamine 6G' Lake, etc.), anthraquinone pigments such as C.I. Pigment Red 177 (Dianthraquinonyl Red, etc.), thioindigo pigments such as C.I. Pigment Red 88 (Thioindigo Bordeaux, etc.), perinone pigments such as C.I. Pigment Red 194 (Perinone Red, etc.), perylene pigments such as C.I. Pigment Red 149 (Perylene Scarlet, etc.), quinacridone pigments such as C.I. Pigment violet 19 (unsubstituted quinacridone, CINQUASIA Magenta RT-355T; manufactured by Ciba Japan) and C.I. Pigment Red 122 (Quinacridone Magenta, etc.), isoindolinone pigments such as C.I. Pigment Red 180 (Isoindolinone Red 2BLT, etc.), and alizarin lake pigments such as C.I. Pigment Red 83 (Madder Lake, etc.). Examples of pigments exhibiting a blue or cyan color include disazo pigments such as C.I. Pigment Blue 25 (Dianisidine Blue, etc.), phthalocyanine pigments such as C.I. Pigment Blue 15 (Phthalocyanine Blue, etc.) and C.I. Pigment Blue 15:3 (IRGALITE BLUE GLVO; manufactured by Ciba Japan), acidic dye lake pigments such as C.I. Pigment Blue 24 (Peacock Blue Lake, etc.), basic dye lake pigments such as C.I. Pigment Blue 1 (Victoria Pure Blue BO Lake, etc.), anthraquinone pigments such as C.I. Pigment Blue 60 (Indanthrone Blue, etc.), and alkali blue pigments such as C.I. Pigment Blue 18 (Alkali Blue V-5:1). Examples of pigments exhibiting a green color include phthalocyanine pigments such as C.I. Pigment Green 7 (Phthalocyanine Green) and C.I. Pigment Green 36 (Phthalocyanine Green), and azo metal complex pigments such as C.I. Pigment Green 8 (Nitroso Green). Examples of pigments exhibiting an orange color include isoindoline pigments such as C.I. Pigment Orange 66 (Isoindoline Orange) and anthraquinone pigments such as C.I. Pigment Orange 51 (Dichloropyranthrone Orange). Examples of pigments exhibiting a black color include carbon black, titanium black, and aniline black. Specific examples of white pigments that can be used include basic lead carbonate (2PbC03Pb(OH)2, also known as silver white), zinc oxide (ZnO, also known as zinc white), titanium oxide (Ti02, also known as titanium white), and strontium titanate (SrTi03, also known as titan strontium white). Titanium oxide has, compared with other white pigments, a low specific gravity, a high refractive index, and is chemically and physically stable, and therefore has high hiding power and coloring power as a pigment and, furthermore, has excellent durability toward acids, alkalis, and other environments. It is therefore preferable to use titanium oxide as the white pigment. It is of course possible to use another white pigment (which can be any white pigment, in addition to the white pigments cited above) as necessary. For dispersion of the colorant, for example, a dispersing machine such as a ball mill, a sand mill, an attritor, a roll mill, a jet mill, a homogenizer, a paint shaker, a kneader, an agitator, a Henschel mixer, a colloidal mill, an ultrasonic homogenizer, a pearl mill, or a wet type jet mill may be used. For dispersion of the colorant, a dispersant such as a surfactant may be added. Furthermore, when the colorant is added, as a dispersion adjuvant, it is also possible to use a synergist as necessary according to the various types of colorant. The dispersion adjuvant is preferably used at at least 1 part by mass but no greater than 50 parts by mass relative to 100 parts by mass of the colorant. When a pigment is used, the ink composition used in the present invention preferably comprises a dispersant in order to disperse the pigment in the ink composition in a stable manner. The dispersant for the pigment is preferably a polymeric dispersant. The 'polymeric dispersant' referred to in the present invention means a dispersant having a weight-average molecular weight of at least 1,000. The content of the dispersant in the ink composition is appropriately selected according to the intended application, but it is preferably 0.05 to 15 mass% relative to the mass of the entire ink composition. In the colored ink composition, a solvent may be added as a dispersion medium for various components such as the colorant, or the polymerizable compound, which is a low molecular weight component, may be used as a dispersion medium without using a solvent, and since the colored ink composition of the present invention is preferably an actinic radiation curing type liquid and the colored ink composition is cured after being applied on top of a recording medium, it is preferable for it to be solvent-free. This is because, if solvent remains in the cured object formed from the cured ink composition, the solvent resistance is degraded and the VOC (Volatile Organic Compound) problem of residual solvent occurs. From this viewpoint, it is preferable to use the polymerizable compound as a dispersion medium. Among them, it is preferable to select a polymerizable compound having a low viscosity in terms of improvement of dispersion suitability and handling properties of the photocurable composition. In addition, the colored ink composition and the clear ink (C2) preferably have a content of solvent, including water, of no greater than 5 mass%, more preferably 3 mass%, yet more preferably 1 mass%, and particularly preferably none. However, this does not exclude the colored ink composition and the clear ink (C2) containing a small amount of water as moisture. Since excellent coloration is achieved by finer particles, it is preferable for the average particle size of the colorant used here to be at least 0.01 urn but no greater than 0.4 urn, and more preferably at least 0.02 urn but no greater than 0.2 urn. In order to make the maximum particle size be no greater than 3 urn, and preferably no greater than 1 urn, it is preferable for the colorant, the dispersant, and the dispersion medium to be selected, and dispersion conditions and filtration conditions to be set. By such control of particle size, clogging of a head nozzle can be suppressed, and the storage stability of the ink composition, and the transparency and curing sensitivity of the ink composition can be maintained. In the present invention, by using the dispersant having excellent dispersibility and stability which is described above, a uniform and stable dispersed substance can be obtained even when a fine particulate colorant is used. The particle size of the colorant may be measured by a known measurement method. Specifically, it may be measured by a centrifugal sedimentation light transmission method, an X-ray transmission method, a laser diffraction/scattering method, or a dynamic light scattering method. In the present invention, a value obtained by measurement using the laser diffraction/scattering method is employed. The content of the colorant may be selected appropriately according to the color and the intended application, but from the viewpoint of image density and storage stability, it is preferably 0.5 to 30 mass% relative to the mass of the entire colored ink composition, more preferably 1.0 to 20 mass%, and particularly preferably 2.0 to 10 mass%. (Other components) The ink composition used in the present invention may comprise as necessary, in addition to the above-mentioned components, a surfactant, a polymerization inhibitor, a sensitizer, a co-sensitizer, a UV absorber, an antioxidant, an antifading agent, a conductive salt, a polymer compound, a basic compound, a leveling additive, a matting agent and, for adjusting film physical properties, a polyester resin, polyurethane resin, vinyl resin, acrylic resin, rubber resin, or wax, etc. They are described in JP-A-2009-185186 and may be used in the present invention as well. In the present invention, the clear ink composition preferably comprises a surfactant. Furthermore, the colored ink composition may comprise a surfactant, however it is preferable for the colored ink composition not to comprise a surfactant. Examples of the surfactant used in the present invention include the surfactants below. For example, those described in JP-A-62-173463 and JP-A-62-183457 can be cited. Specific examples thereof include anionic surfactants such as dialkylsulfosuccinic acid salts, alkylnaphthalenesulfonic acid salts, and fatty acid salts, nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, acetylene glycols, and polyoxyethylene/polyoxypropylene block copolymers, and cationic surfactants such as alkylamine salts and quaternary ammonium salts. As the above known surfactants, an organofluoro compound may be used. The organofluoro compound is preferably hydrophobic. Examples of the organofluoro compound include fluorine-based surfactants, oil-like fluorine-based compounds (e.g. fluorine oils), and solid fluorine compound resins (e.g. tetrafluoroethylene resin), and those described in JP-B-57-9053 (8th to 17th columns) and JP-A-62-135826. The other surfactant used in the present invention is not particularly limited to the surfactants described above, and it may be an additive that, for the concentration added, is capable of reducing the surface tension efficiently. Preferred examples of the surfactant include a silicone compound. Furthermore, among the silicone compounds, a silicone compound having an ethylenic double bond in the molecule is preferable. Adhesion to an image can be further improved by the use of the polymerizable compound and a silicone compound having an ethylenic double bond in the molecule. Specific examples of the silicone compound include BYK-300, BYK-302, BYK-306, BYK-307, BYK-310, BYK-315, BYK-320, BYK-322, BYK-323, BYK-325, BYK-330, BYK-331, BYK-333, BYK-337, BYK-344, BYK-370, BYK-375, BYK-377, BYK-UV3500, BYK-UV3510, and BYK-UV3570 manufactured by BYK-Chemie; TEGO-Rad 2100, TEGO-Rad 2200N, TEGO-Rad 2250, TEGO-Rad 2300, TEGO-Rad 2500, TEGO-Rad 2600, and TEGO-Rad 2700 manufactured by Degussa; and Glanol 100, Glanol 115, Glanol 400, Glanol 410, Glanol 435, Glanol 440, Glanol 450, B-1484, Polyflow ATF-2, KL-600, UCR-L72, and UCR-L93 manufactured by Kyoeisha Chemical Co., Ltd. They may be used singly or as a mixture of a plurality thereof. The amount of surfactant added is not particularly limited, but from the viewpoint of stable discharge properties and surface tension being in a desired range, it is preferably 0.05 to 5 mass% of the entire ink, more preferably 0.1 to 3 mass%, and particularly preferably 0.3 to 2 mass%. In the drawing mode of wide format equipment, drawing conditions for shingling (interlacing) are determined for each of the set resolutions. Specifically, since shingling drawing is carried out by dividing the width Lw (nozzle array length) of a discharge nozzle array of an ink jet head by the number of passes (times of repetition of scanning), the swath width varies depending on the nozzle array width of the ink jet head and the number of passes (number of divisions for interlacing) in the main scanning direction and the sub scanning direction. Details of shingling drawing by a multi pass method are explained in for example JP-A-2004-306617. As one example, the relationship between the swath width and the number of passes in shingling drawing when a QS-10 head (100 dpi, 256 nozzles) manufactured by a FUJIFILM Dimatix is as in the Table below (Table 1). The swath width that is expected by drawing is the value obtained by dividing the nozzle array width by the product of the number of passes in the main scanning direction and the number of passes in the sub scanning direction. Table 1 (Configuration of UV irradiation section) As shown in FIG. 4, the provisional curing light sources 32A and 32B are disposed on left and right sides of the ink jet head 24 in the carriage movement direction (Y direction). Furthermore, the main curing light sources 34A and 34B are disposed on the downstream side, in the recording medium transport direction (X direction), of the ink jet head 24. The main curing light sources 34A and 34B are disposed further outside (position further away) than the provisional curing light sources 32A and 32B in the Y direction from the ink jet head 24. The main curing light sources 34A and 34B are configured so that they can move in a direction (-X direction) opposite to the recording medium transport direction, and their positions can be changed so as to be aligned with the provisional curing light sources 32A and 32B and the ink jet head 24 along the carriage movement direction. A color ink droplet that has been discharged from a nozzle (nozzle contained in the nozzle array 61Y, 61M, 61C, 61K, 61LC, or 61LM) for a colored ink composition (color ink) of the ink jet head 24 and has landed on the recording medium 12 is irradiated with UV for preliminary curing by means of the provisional curing light source 32A (or 32B) that passes thereabove immediately thereafter. Furthermore, an ink droplet on the recording medium 12 that has passed through the printing region of the ink jet head 24 accompanying intermittent transport of the recording medium 12 is irradiated by UV for main curing by means of the main curing light sources 34A and 34B. When the banding phenomenon of a clear ink layer is examined in detail, the color ink requires pinning light in order to fix the position of the fired droplet, but since the clear ink layer forms a high gloss surface layer in the case of the clear ink C1, there is little necessity for pinning a droplet at the fired position. Instead, it is preferable that when forming a clear ink (C1) layer, the amount of pinning light corresponding to the discharge position for the clear ink (C1) is set to OFF (0 mJ/cm2) or the amount of irradiation light is decreased so that landed droplets are not pinned, and the ink is made to spread easily while wet, thus achieving planarization and uniformization of the layer. On the other hand, when low surface gloss is required, pinning is carried out immediately after a droplet has landed, thus preventing the ink from spreading while wet and increasing the roughness of the clear ink. When low surface gloss is obtained, the clear ink C2 is more suitable than the clear ink C1, and it is preferable to irradiate with pinning light. Furthermore, in the present example, the clear ink that has been discharged from the nozzle for a clear ink (the nozzle contained in the nozzle arrays 61CL1 and 61CL2) and has landed on the recording medium is irradiated with substantially the same amount of UV as that for the main curing treatment by means of the main curing light source 34A that has been moved to a position where UV irradiation corresponding to the position where the clear ink is discharged is possible. The provisional curing light sources 32A and 32B may be switched on at the same time during printing by the ink jet head 24, but the lifespan of the light sources can be increased by switching on only the provisional curing light source that is to the rear with respect to movement of the carriage in the main scanning direction. Furthermore, the main curing light sources 34A and 34B are switched on at the same time during printing by the ink jet recording equipment 10. In a drawing mode where the scanning speed is low, one thereof may be switched off, and the timing with which the provisional curing light sources 32A and 32B are made to start emitting light can be the same as or different from the timing with which the main curing light sources 34A and 34B are made to start emitting light. (Explanation of movement of main curing light source) FIG. 5 is a perspective view showing a configuration example of a movement mechanism (light source movement part) 35 for the main curing light source 34A. The light source movement part 35 shown in this figure employs a rack and pinion linear movement mechanism. That is, the light source movement part 35 comprises a shaft 35A that is fixedly disposed along the recording medium transport direction, which is the direction of movement for the main curing light source 34A, a rack 35B that is mounted on a case of the main curing light source 34A and has tooth-shaped asperities along the shaft 35A, a drive motor 35D that has a pinion gear 35C mounted on a rotating shaft, and an optical position sensor 35F for detecting a detection piece 35E formed on an end part of the rack. When the rotational shaft of the drive motor 35D is rotated, the pinion gear 35C rotates, the rack 35B moves along the shaft 35A due to meshing between the pinion gear 35C and the rack 35B, and the main curing light source 34A moves along the shaft 35A together with the rack 35B. When the detection piece 35E provided at the extremity of the rack 35B enters a detection range of the position sensor 35F, rotation of the drive motor 35D is stopped, and the main curing light source 34A stops at a predetermined position. A movement mechanism having the same configuration may be provided on the main curing light source 34B positioned on the side opposite to the main curing light source 34A relative to the ink jet head 24 so that it is configured to be movable. Furthermore, the main curing light source 34A may be configured to be movable between a plurality of positions by providing a plurality of the position sensors 35F. (Explanation of image formation process) The ink jet recording equipment 10 shown in the present example is configured so that an image having a multi-layer structure is formed by layering a image layer (illustrated by reference numeral 14 in FIG. 1) formed from a color ink (Y, M, C, K, LC, LM, etc.) and a clear ink layer (illustrated by reference numeral 16 in FIG. 1) formed from a clear ink. The amount of UV irradiation is controlled according to the order of layer formation and UV absorption characteristics (ink curing characteristics). For example, when a white ink composition is used as an optional component, since the white ink composition contains titanium oxide, zinc oxide, etc. as a pigment, the UV transmittance is poor compared with a color ink and a clear ink, and when the same amount of UV per unit volume as for the color ink or the clear ink is applied, the curing time is long. In order to eliminate any difference in curing characteristics caused by the UV transmission characteristics of the clear ink and the color ink, irradiation with UV is controlled so that the amount of UV irradiation per unit time is larger for the clear ink than for the color ink. A specific example of such image formation is described later. From the viewpoint of UV transmission, the black ink composition is classified as an ink that requires a longer curing time, but since it is used for formation of an image layer and it is necessary to prevent interference between fired droplets by subjecting it to preliminary curing immediately after firing droplets, it is classified as a color ink. An image was printed as follows using an ink set comprising the yellow ink, the magenta ink, the cyan ink, the black ink, and the clear ink described in Tables 2 to 11, and evaluation was carried out. Droplets of the ink composition obtained were fired onto a sheet of coated paper (OK-TOP, Oji Paper Co., Ltd.) and irradiated by passing under a light beam of a UV light-emitting diode (UV-LED) to thus cure the ink, thereby giving a printed material. In this example, the colored ink and the clear ink were discharged using inkjet recording equipment having a piezo type Q-class Sapphire QS-256/10 inkjet head (FUJIFILM DIMATIX, number of nozzles 256, liquid droplet volume 10 pL, 50 kHz, ink affinity treatment: silicon oxide), and as a light-emitting diode (UV-LED) for curing an NC4U134 manufactured by Nichia Corporation was used. The LED output UV light at a wavelength of 385 nm from 1 chip. With regard to an image formation method in a high surface gloss mode, due to a clear ink layer (C1) being formed so as to overlay a color layer formed, as shown in FIG. 6 the head and the LED light source were divided so that the upstream side in the direction of transport of the recording medium was a color layer and the downstream side was a clear ink layer. The color layer was exposed such that the illumination intensity on the recording medium surface immediately after landing was fixed at 0.8 W/cm2 and the exposure when one lamp was passing thereabove was set at 10 mJ/cm2 by changing the transport speed. Furthermore, in the present example, exposure was carried out about 0.5 sec. after landing. The clear ink (C1) layer was cured with the light sources 34A and 34B while substantially not turning ON the light source 32B-2. Exposure was carried out by fixing the illumination intensity on the recording medium surface at 1,200 mW/cm2 and setting the exposure at 30 mJ/cm2 when one lamp was passing thereabove by changing the transport speed. The temperature control section 50, the pre-temperature control section 52, and post-temperature control section 54 described in FIG. 3 were all set to 55°C. With regard to an image formation method in a low surface gloss mode, image formation was carried out in the same manner as in the image formation method for the high surface gloss mode except that the clear ink (C1) layer used for the high surface gloss mode was changed to a clear ink (C2) layer, and the light source 32B-2 was turned ON. Images having a clear ink used in the evaluation below were solid images of yellow (Y), magenta (M), cyan (C), black (K), 3CG (YMC), and 4CG (YMCK) when discharged with a color density setting on a PC (personal computer) of 100%. A clear image was outputted on the image layer by setting the ink discharge limit for the clear ink at 30% (the maximum ink discharge in the mode being 100%). The evaluation below was carried out for a multiple layer formation image thus obtained using a colored ink and a clear ink. 100 sheets of samples in which an image was outputted on a coated paper (OK-TOP: 128 g/m2, Oji Paper Co., Ltd.) at the same size as that of the output image sample obtained in the high surface gloss mode were stacked and placed in a constant temperature and constant humidity chamber at a temperature of 40°C and a humidity of 30% for 16 hours. Subsequently, the image surface was evaluated. Evaluation of an image was carried out for blocking resistance of images in which a clear ink layer was overlaid on a color layer. A: no trace of ink transfer to print surface. B: very slight trace of white base of stacked coated paper transferred to print surface but at a level that was not a problem in practice. C: slight trace of white base of stacked coated paper transferred to print surface (less than 5% of the whole area and spot like) but at a level that was not a problem in practice. D: a large number of traces of white base of stacked coated paper transferred to print surface (at least 5% of the whole area or less than 5% but aggregated and not spot like) and at a level that was a problem in practice. E: a large number of traces of white base of stacked coated paper transferred to print surface (at least 50% of the whole area) and at a level that was a problem in practice. Evaluation of surface gloss in high surface gloss mode and low surface gloss mode was carried out by visually examining an image sample outputted as above. The sample was wrapped around a rod having a thickness of 10 cm, the state of the reflection of a fluorescent lamp (image clarity) was examined visually, and the surface gloss was evaluated using the ranking below. -Evaluation ranking for surface gloss in high surface gloss mode- A: fluorescent lamp was clearly reflected, and an ideal smooth surface was obtained. B: fluorescent lamp was slightly blurred depending on the reflection angle but at a level that was not a problem in practice. C: fluorescent lamp was reflected with edges slightly blurred but at a level that was not a problem in practice. D: fluorescent lamp reflection was slightly blurred from all angles examined, and at a level that was a problem in practice. E: fluorescent lamp reflection was blurred from all angles examined and the surface was rough at a level that was a problem in practice. -Evaluation ranking for surface gloss in low surface gloss mode-A: fluorescent lamp reflection was blurred from all angles examined and the surface was rough but at a level that was not a problem in practice. B: fluorescent lamp reflection was blurred from all angles, or was very clear at a level that was a problem in practice. In accordance with the inkjet recording method in the high surface gloss mode, a sample with an image formed from multiple layers was formed using an ink set of the Examples or Comparative Examples of Table 2 to Table 11 above a sheet of a transparent substrate (polycarbonate). The sample was produced so that the average thickness of the cured film was 30 urn. A measurement piece with dimensions of 5 cm x 2 cm was cut out from each sample obtained and subjected to a stretch test using a stretching machine under the temperature conditions below, thus measuring the stretching ratio. Machine used: Tensilon (Shimadzu Corporation) Measurement conditions: length at break was measured at room temperature and a tensile speed of 50 millimeter/min., and stretching ratio was calculated. The stretching ratio referred to here was determined from {( length at break -length before stretching )/length before stretching} x 100 ((e.g.) when there was break at 10 cm, {(10 cm - 5 cm)/5 cm} x 100 = 100% stretch). The evaluation criteria for stretchability were as follows. Since the stretchability of a clear ink is influenced by a base color layer, the ranking below was applied using a value obtained from (stretching ratio of image for forming multiple layers)/(stretching ratio of single layer color layer image) as an index. A: (stretching ratio of image for forming multiple layers)/(stretching ratio of single layer color layer image) was at least 0.8 and at a level that was not a problem in practice. B: (stretching ratio of image for forming multiple layers)/(stretching ratio of single layer color layer image) was at least 0.7 but less than 0.8 and at a level that was not a problem in practice. C: (stretching ratio of image for forming multiple layers)/(stretching ratio of single layer color layer image) was at least 0.5 but less than 0.7 and at a level that was not a problem in practice. D: (stretching ratio of image for forming multiple layers)/(stretching ratio of single layer color layer image) was at least 0.3 but less than 0.5 and at a level that was a problem in practice. E: (stretching ratio of image for forming multiple layers)/(stretching ratio of single layer color layer image) was less than 0.3 and at a level that was a problem in practice. The evaluation results above are given in Table 2 to Table 11. Y, M, C, K, Lm, and Lc in the 'Ink set' column correspond to colored ink compositions, CL1 denotes the clear ink composition (C1), and CL2 denotes the clear ink composition (C2). '-' means none was contained. Explanation of Reference Numerals and Symbols 10 ink jet recording equipment, 12 recording medium, 14 image layer, 16 clear ink layer, 18 white layer, 20 main body, 22 support legs, 24 ink jet head, 26 platen, 28 guide mechanism, 30 carriage, 32A, 32B provisional curing light source, 34A, 34B main curing light source, 35 movement mechanism (light source movement part), 35A shaft, 35B rack, 35C pinion gear, 35D drive motor, 35E detection piece, 35F position sensor, 36 ink cartridge, 38 mounting section, 40 nip roller, 42 supply-side roll, 44 wind-up roll, 46 guide, 50 temperature control section, 52 pre-temperature control section, 54 post-temperature control section, 61, 61C, 61M, 61Y, 61K, 61LC, 61LM, 61CL1, 61CL2 nozzle array, 61-1 upstream side region, 61-2 downstream side region, 70 supply pump, 72 subtank, 74 pressure-adjusting section, 76 valve, 77 pressurizing/decompressing pump, 78 pressure gauge, 102 control device, 104 recording medium transport control section, 106 carriage drive control section, 108 light source control section, 110 image processing section, 112 discharge control section, 114 transport drive section, 116 main scanning drive section, 120 input device, 124 information storage section, 128 head drive circuit, 130 encoder, 132 sensor. « Claims What is claimed is: 1. An actinic radiation-curing type ink set comprising a colored ink composition and a clear ink composition (C1), the colored ink composition comprising (Component A1) a radically polymerizable compound, (Component B1) a polymerization initiator, and (Component D) a colorant, and the clear ink composition (C1) comprising (Component A2) a radically polymerizable compound, (Component B2) a polymerization initiator, and (Component S) an organic solvent. 2. The actinic radiation-curing type ink set as claimed in Claim 1, wherein it further comprises a clear ink composition (C2) that does not comprise an organic solvent. 3. The actinic radiation-curing type ink set as claimed in Claim 2, wherein the clear ink composition (C2) comprises (Component A3) a radically polymerizable compound and (Component B3) a polymerization initiator. 4. The actinic radiation-curing type ink set as claimed in Claim 3, wherein the colored ink composition comprises at least a bisacylphosphine oxide as the polymerization initiator, and the clear ink composition (C1) and/or the clear ink composition (C2) comprise a monoacylphosphine oxide as the polymerization initiator. 5. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 4, wherein the colored ink composition does not contain an organic solvent. 6. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 5, wherein the actinic radiation-curing type ink set is for forming multiple layers. 7. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 6, wherein the colored ink composition comprises (Component A1-1) an A/-vinyl compound as Component A1. 8. The actinic radiation-curing type ink set as claimed in Claim 7, wherein Component A1-1 is /V-vinylcaprolactam. 9. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 8, wherein said Component S comprises at least one type selected from the group consisting of an alcohol, a polyhydric alcohol, a polyhydric alcohol ether, a nitrogen-containing compound, and a sulfur-containing compound. 10. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 9, wherein said Component S comprises at least one type selected from the group consisting of an alcohol, a polyhydric alcohol, and a polyhydric alcohol ether. 11. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 10, wherein said Component S has a boiling point of 65°C to 250°C. 12. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 11, wherein said Component S has a content in the clear ink composition (C1) of 1 to 80 mass%. 13. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 12, wherein said Component S comprises at least one type selected from the group consisting of methanol, isopropyl alcohol, 1-butyl alcohol, 1-ethoxy-2-propanol, ethylene glycol monomethyl ether, and diethylene glycol monobutyl ether. 14. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 13, wherein the colored ink composition comprises (Component A1-2) a compound represented by Formula (a-2) as Component A1, wherein in Formula (a-2), R1, R2, and R3 independently denote a hydrogen atom, a methyl group, or an ethyl group and X2 denotes a single bond or a divalent linking group. 15. The actinic radiation-curing type ink set as claimed in any one of Claims 1 to 14, wherein the colored ink composition comprises a monofunctional radically polymerizable compound at 60 to 100 mass% relative to the total amount of Component A1. 16. An inkjet recording method using the actinic radiation-curing type ink set as claimed in any one of Claims 1 to 15, the method comprising, in this order: an image formation step of forming a color image by discharging the colored ink composition onto a recording medium; and a clear ink layer formation step of forming a clear ink layer by discharging the clear ink composition (C1). 17. The inkjet recording method as claimed in Claim 16, wherein it further comprises a step of heating the recording medium at 30°C to 80°C subsequent to the clear ink layer formation step. 18. The inkjet recording method as claimed in Claim 16 or 17, wherein it comprises: a scanning step of moving, in a first direction relative to the recording medium, an inkjet head having a plurality of nozzle arrays comprising a first nozzle array having a plurality of nozzles arranged for discharging the colored ink composition and a second nozzle array having a plurality of nozzles arranged for discharging the clear ink composition (C1); a relative movement step of reciprocating the recording medium relative to the inkjet head in a second direction that is not parallel to the first direction; a discharge control step of dividing the nozzle array into a plurality of regions in the second direction and controlling ink discharge from the inkjet head for each divided nozzle region unit; and an actinic radiation irradiation step of irradiating with actinic radiation the ink that has been discharged from the inkjet head in the discharge control step and has been deposited on the recording medium; the actinic radiation irradiation step being a step of carrying out the irradiation with actinic radiation by dividing the actinic radiation irradiation area into a plurality of regions so as to correspond to the divided nozzle regions and controlling the amount of light for each region of the divided irradiation regions. 19. The inkjet recording method as claimed in Claim 18, wherein the actinic radiation irradiation area is divided into two regions, the illumination intensity of an irradiation light source for the first region is 100 mW/cm2 to 800 mW/cm2, and the illumination intensity of an irradiation light source for the second region is 800 mW/cm2 to 1,600 mW/cm2. 20. The inkjet recording method as claimed in any one of Claims 16 to 19, wherein the minimum droplet volume for discharging the colored ink composition is at least 5 pL but less than 20 pL, and the minimum droplet volume for discharging the clear ink composition (C1) is at least 20 pL but no greater than 60 pL. 21. A printed material obtained by the method as claimed in any one of Claims 16 to 20. 22. Use of the actinic radiation-curing type ink set as claimed in any one of Claims 1 to 15 as an actinic radiation-curing type inkjet ink set for formation of multiple layers.