[0001]The present invention relates to a coated metal plate.
Background technique
[0002]Various lighting fixtures and various video display devices of, by emitting visible light, and has functions such or out copy or brighten the surroundings, an image. In these devices, a reflector around and behind the light source is provided, according reflector that reflects light, or to improve the brightness of light, and or by changing the traveling direction of light. In this case, in order to suppress the reduction in light quantity caused when the light is reflected by the reflector, high visible light reflectance is required on the surface of the reflector. To accommodate such needs, conventional, metal plate coating is formed of highly reflective white (coated metal plate) have been proposed (e.g., see Patent Documents 1 and 2 below .).
CITATION
Patent Document
[0003]
Patent Document 1: WO 2011/034216
Patent Document 2: JP 2011-36838 JP
Patent Document 3: JP 2005-144942 Patent Publication
Patent Document 4: JP-A 1-49629 Patent Publication
Patent Document 5: JP 1-153764 JP
Summary of the Invention
Problems that the Invention is to Solve
[0004]
　Here, if the high painted metal plate reflectivity as described above can be particularly used in lighting equipment and the like, such coated metal plates are often exposed to the air. At this time, if dust or the like present in the air is gradually deposited on the surface of the coated metal plate, a coated metal plate itself despite having a high reflectivity, reduced reflective performance by adhering dust It is considered to continue to. Therefore, either not adhered dust or the like in the how the surface of the coated metal plate having a high reflectance is important.
[0005]
　The dust from adhering to the outermost surface of the coated metal plate, it is caused by dust or the like or a coated metal plate is charged. Accordingly, the present inventors have found that to improve the antistatic properties of the coating layer formed on the metal plate and conceived to be important. Here, the coating film layer excellent in antistatic properties, is also a coating layer having a high conductivity. The coating layer having such a high conductivity, a technique for expressing the conductivity by ensuring the continuity in the depth direction of the metal plate is a conductor from the surface of the coating film is widely known . However, the coating layer on the metal plate coated with an insulating layer, it is difficult to apply the conductive technology.
[0006]
　On the other hand, as a means for obtaining a coating layer excellent in antistatic properties, for example, it can be applied techniques disclosed in Patent Documents 3 to 5.
[0007]
　For example, the Patent Document 3, as means for imparting antistatic properties to the coated metal plate coated with an insulating coating, is lower the position on the triboelectric series of the insulating coating film (i.e., negatively charged by) easily, easily charged method for inhibiting the adhesion of dust is disclosed in negative. However, the method disclosed in Patent Document 3, because it depends on the charging property such as dust, high 耐埃 adhesion (i.e., excellent antistatic properties) is a problem that it is difficult to express the is there.
[0008]
　The aforementioned Patent Document 4, discloses a method of providing an antistatic layer with an insulating layer on a metal substrate, as the antistatic agent, carbon powder, copper powder and other metal powder, surface active agents, conductive plasticizers are exemplified. However, the antistatic agent of metal powder such as dark color, including the carbon powder and copper powder has a problem of reducing the reflectance of the high reflection coating film provided as a base.
[0009]
　The aforementioned Patent Document 5, the addition of white conductive whisker coating film techniques to provide various colorable antistatic property to the color (antistatic) coated metal plate is disclosed. However, in Patent Document 5, 40 [mu] m ~ 50 [mu] m as the thickness of the coating film added with the whiskers and are exemplified, because a large amount use of expensive whiskers compared to other materials, the antistatic metal plate cheap there is a problem that can not be provided.
[0010]
　Thus, the antistatic techniques as disclosed in the above Patent Documents 3 to 5, it is difficult to easily realize an excellent antistatic property. Also, when considering the application of superior coated metal plate antistatic property, it is preferred such coated metal plate is excellent in workability.
[0011]
　The present invention has been made in view of the above problems, it is an object of the present invention, while maintaining excellent processability and reflectance characteristics, a more convenient and more excellent antistatic property method which can be realized by, it is to provide a coated metal plate.
Means for Solving the Problems
[0012]
　The present inventors have made intensive studies in order to solve the above problems, than is the present invention has been completed as described in detail below.
　The gist of the present invention is as follows.
[0013]
(1) positioned above at least one surface of the metal plate, comprises a coating layer comprising one or more layers, the coating layer consisting of the one or more layers, the average length is 1 [mu] m ~ 10 [mu] m, and a is 0.1 [mu] m ~ 0.5 [mu] m average thickness, the antistatic layer containing titanium oxide as an antistatic agent of a needle-like shape whose surface is coated with a conductive layer having conductivity, at least one layer has any one or more layers of said coating layer has an average particle size and containing a white paint containing titanium oxide of 200 nm ~ 400 nm, the content of the antistatic agent in the antistatic layer , the the total solid content of the antistatic layer is from 5 wt% to 30 wt%, the total light reflectance is 85% or more, coated metal plate.
(2) The surface resistivity of the antistatic layer, 1 × 10 13 or less Omega, coated metal sheet according to (1).
(3) the thickness of the antistatic layer is 2 [mu] m ~ 30 [mu] m, coated metal sheet according to (1) or (2).
(4) In the antistatic layer, the presence proportion of those long axis of the titanium oxide is inclined with respect to the surface normal direction of the metal plate having the needle-like shape, antistatic layer of titanium oxide containing the number is 95% or more of, (1) - coated metal sheet according to any one of (3).
(5) between the metal plate and the coating layer, the insulating layer further comprises, (1) - coated metal sheet according to any one of (4).
(6) the antistatic layer is located as the outermost layer of the coated metal plate, (1) to (5) coated metal sheet according to any one of.
(7) said coating layer is composed of a plurality of layers, a layer located further surface layer side than the antistatic layer of said coating layer is a layer having conductivity, (1) to (5) coated metal sheet according to any one.
(8) The antistatic layer is composed of a plurality of layers, the more the antistatic layer located on the surface layer side, the concentration of the antistatic agent is high, according to any one of (1) to (7) coated metal plate.
Effect of the invention
[0014]
　According to the present invention described above, while maintaining excellent processability and reflectance characteristics, better antistatic properties, can be realized by a simpler method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015]
[FIG. 1A] is an explanatory view schematically showing a layer structure of coated metal plate according to the embodiment of the present invention.
[FIG 1B] is an explanatory view schematically showing a layer structure of coated metal plate according to the embodiment.
FIG. 2 is an explanatory view schematically showing a layer structure of coated metal plate according to the embodiment.
FIG. 3 is an explanatory view of the antistatic layer coated metal plate is provided according to the embodiment shown schematically.
FIG. 4 is an explanatory diagram for describing antistatic agent antistatic layer contains according to the embodiment.
FIG. 5 is an explanatory diagram for explaining an antistatic layer according to the embodiment.
6 is an explanatory diagram for describing the antistatic layer according to the embodiment.
7 is an explanatory diagram for explaining an antistatic layer according to the embodiment.
8 is an explanatory diagram for describing the antistatic layer according to the embodiment.
9 is an explanatory diagram for describing the antistatic layer according to the embodiment.
DESCRIPTION OF THE INVENTION
[0016]
　Reference will now be described in detail preferred embodiments of the present invention. In the specification and the drawings, components having substantially the same function and structure are a repeated explanation thereof by referring to the figures.
[0017]

　First, referring to FIGS. 1A ~ FIG. 2, the overall structure of a coated metal plate according to the embodiment of the present invention will be briefly described. Figure 1A ~ FIG. 2 is an explanatory diagram of the layer structure of a coated metal plate according to the present embodiment shown schematically.
[0018]
　In the following description, as shown in FIGS. 1A and 1B, the thickness direction of the coated metal plate as a convenience Z-axis direction, X-axis in the width direction of the coated metal plate shown in FIGS. 1A and 1B and direction, the depth direction and the Y-axis direction.
[0019]
　Coated metal sheet 10 according to this embodiment, as shown in FIGS. 1A and 1B, the metal plate 101, the coating film layer 103 which is an example of a film layer located above the surface of the metal plate 101, the provided.
[0020]
　Here, "above the surface of the metal plate 101 ', as schematically shown in FIG. 1A, not only when the direct coating film layer 103 on the metal plate 101 is stacked, schematically in Figure 1B manner as shown in, one or more layers 105 on the metal plate 101 is formed, the case where coating film layer 103 on the outermost surface of one or more layers 105 are formed.
[0021]
　Further, in FIGS. 1A and 1B, as is one of the paint over the surface coating layer 103 of the metal plate 101 is illustrated if provided, schematically shown in FIG. 2, the metal plate 101 for both surfaces, that coating film layer 103 may be provided, of course. In FIG. 2, but directly coating film layer 103 on the metal plate 101 is illustrated if provided, also in this case, as shown in FIG. 1B, the metal plate 101 and the coating film layer 103 between may exist one or more layers 105.
[0022]
　Metal plate 101 is used as the base material of the coated metal plate according to the present embodiment. Such type of metal plate 101 is not limited in particular, may be a variety of steel sheet, may be a metal plate made of an alloy containing iron, nonferrous metals such as aluminum and titanium it may be a metal plate. Type of the metal plate 101, in consideration of the strength, workability, and the like such as various properties required for the coated metal plate 10 according to the present embodiment, may be selected as appropriate from among metals such as described above.
[0023]
　Coating film layer 103 at least formed above the one surface of the metal plate 101 as described above, a layer comprising one or more layers, coating a paint containing a predetermined material on the metal plate 101, It is formed by drying. In coated metal sheet 10 according to the present embodiment, as one of the coating film layer 103, antistatic layer containing at least an antistatic agent is formed.
[0024]
　This coating film layer 103 and the antistatic layer will be described in detail later.
[0025]
　Further, as schematically illustrated in Figure 1B, between the metal plate 101 and the coating film layer 103 may be one or more layers 105 are formed. Such layer 105 is not limited in particular, as long as it does not inhibit the function of the coating film layer 103 to be described later, may be any layer is formed. For example, the metal plate 101 to be used as a base material, when various kinds of surface treatment is a metal plate which has been subjected, a surface treatment layer formed on the surface of the metal plate corresponds to the layer 105.
[0026]
　Above with reference to FIGS. 1A ~ FIG. 2, the overall configuration of a coated metal plate 10 according to the present embodiment has been briefly described.
[0027]

　Next, with reference to FIGS. 3-9, the coating film layer 103 covering the metal plate 10 according to the present embodiment, the antistatic layer the coating film layer 103 is provided It will be described in detail.
　Figure 3 is an explanatory view of the antistatic layer coated metal plate is provided according to the present embodiment shown schematically. Figure 4 is an explanatory diagram for explaining an antistatic agent containing an antistatic layer according to the present embodiment. 5 to 9 are explanatory views for explaining an antistatic layer according to the present embodiment.
[0028]
About Antistatic layer]
　As prior mentioned coating film layer 103 according to the present embodiment is composed of one or a plurality of layers, at least one layer of which containing a predetermined antistatic agent charged It has become a prevention layer.
[0029]
　In the following, first, with reference to FIG. 3, the antistatic layer 111 coating film layer 103 is provided according to the present embodiment will be described in detail.
[0030]
　Antistatic layer 111 according to this embodiment, as the coating film layer 103 comprising one or more layers, a layer formed of at least one layer. This antistatic layer 111, as schematically shown in FIG. 3, as an antistatic agent, a titanium oxide 113 having a needle-like shape is contained at least.
[0031]
　4, the structure of the titanium oxide 113 having a needle-like shape is contained in the antistatic layer 111 according to the embodiment shown schematically. Titanium oxide having a needle-like shape to be used as an antistatic agent according to the present embodiment, in order to conductivity and higher ones, as schematically shown in FIG. 4, the surface of titanium oxide are various It is coated with a conductive layer. For conductive layer covering the surface of the titanium oxide is also not limited in particular, as such a conductive layer, such as metal oxides of various metals doped, it is available a known. Hereinafter, the surface of a conductive layer having a conductive titanium oxide of a needle-like shape which is coated, abbreviated as "titanium oxide needle-like shape".
[0032]
　Further, contained in the antistatic layer 111 according to this embodiment, titanium oxide 113 of needle-like shape, as shown in FIG. 4, the average length (average length of the long axis direction of the titanium oxide needle-shaped is) L is a 1 [mu] m ~ 10 [mu] m, and an average length) D of the short-axis direction of the titanium oxide having an average thickness (needle-like shape, a 0.1 [mu] m ~ 0.5 [mu] m.
[0033]
　When the average length L is less than 1μm, in order to achieve a conductivity of antistatic layers 111 contemplated by the present embodiment, should not not to contain more titanium oxide 113, a cost not preferable from the point of view. Further, if the average length L is 10μm exceeded, the antistatic layer 111 according to the present embodiment increases the transmission attenuation of the light as described later, further, titanium oxide 113 is settled in the paint tends to, for example, when painting a roll coater, the oxidation of titanium introduced amount to the coating film is lowered operation stability etc. vary, which is not preferable.
[0034]
　When the average thickness D is less than 0.1μm, in the interior of the antistatic layer 111, it can not be sufficiently realized Ai overlapping of titanium oxide 113 having a needle-like shape, the adhesion of dust, etc. since the causative surface charge can be efficiently transmitted it becomes difficult, undesirably. Further, if the average thickness D is 0.5μm exceeded, that the content of titanium oxide 113 occupying in the thickness direction of the antistatic layer (Z-axis direction thickness as shown in FIG. 3) is increased, antistatic brittle the layer 111, workability undesirably lowered.
[0035]
　In the present embodiment, more preferred average length L of the titanium oxide 113 is 3 [mu] m ~ 8 [mu] m, still more preferably an average length L is 5 [mu] m ~ 6 [mu] m. Further, in the present embodiment, more preferred average thickness D of the titanium oxide 113 is 0.2 [mu] m ~ 0.4 .mu.m, more preferred average thickness D is 0.2 [mu] m ~ 0.3 [mu] m.
[0036]
　In the antistatic layer 111 according to the present embodiment, it may be utilized titanium oxide 113 of needle-like shape having a shape as described above but, after the formation of the antistatic layer 111 of titanium oxide 113 as described above when measuring the average length L and average thickness D may be carried out measured by the following method. That is, from the observation images for each of the surface and cross section of the antistatic layer 111, may be utilized a method for measuring the average length L and average diameter D of titanium oxide 113. The surface observation of the antistatic layer 111, a scanning electron microscope (Scanning Electron Microscope: SEM) can be used. Although not particularly restricted but includes the method of cross-sectional observation of the antistatic layer 111, the buried and perpendicular the thickness direction of the coating film coating the metal plate 10 in air drying epoxy resin, observing the embedded surface after mechanical polishing methods and, focused ion beam (focused ion beam: FIB) using the apparatus, cut out the sample for observation of the thickness of 50 ~ 100 nm as the vertical cross section seen in the paint film from the coated metal plate 10, the transmission type paint film cross section electron microscopy: may be utilized a method in which observed in (Transmission electron microscope TEM).
[0037]
　Furthermore, in the antistatic layer 111, the titanium oxide content 113 of needle-shaped on the total solid content of the antistatic layer 111, and has a 5 mass% to 30 mass%. The content of titanium oxide 113 of needle-like shape, if it is less than 5% by weight relative to the total solid content is too small content of the antistatic agent contained in the antistatic layer 111, the desired since conductivity can be stably embodied becomes difficult, undesirably. Further, more it increases the content of titanium oxide 113 of needle-shaped, to obtain a high conductivity becomes possible. However, the content of titanium oxide 113 of needle-like shape, when the 30 mass% excess relative to the total solids, with a cost disadvantage, that the content of the solid titanium oxide 113 is increased the processability is lowered, unfavorably. Further, in such a case, there is a possibility that significantly enhances the transmission attenuation of the light as described later. Maintaining the titanium oxide content 113 of needle-like shape, with respect to the total solid content of the antistatic layer 111, by 5 mass% to 30 mass%, good processability and transmission attenuation factor of suitable light degree and while it is possible to embody excellent antistatic properties. The content of titanium oxide 113 of needle-like shape, preferably 10% to 25% by weight based on the total solids, more preferably 10 mass% to 20 mass%.
[0038]
　Further, the antistatic layer 111 according to this embodiment, in addition to titanium oxide 113 as described above is antistatic agent may contain various binder resins. Such a binder resin is not particularly limited, it is possible to use various resins commonly used in the paint field of thermoplastic resins and thermosetting resins. Examples of such resins include polyester resins, melamine resins, acrylic resins, isocyanate resins, fluorine resins, epoxy resins, polyamides, polyesteramides, polyvinyl chloride, polyurethane, polycarbonate, polystyrene, and polyolefins, copolymers thereof and mixtures and the like. Such a binder resin may be a water-based resin may be a solvent-based resin.
[0039]
　Moreover, the binder resin is a polyester resin, a melamine resin, an acrylic resin, an isocyanate resin, is preferably at least one resin selected from the group consisting of fluorine resin and epoxy resin, among others, polyester resin is more preferable.
[0040]
　The polyester resin preferably has a number average molecular weight of 5000 to 35000 is more preferred number average molecular weight, from 10,000 to 30,000. The glass transition temperature of the polyester resin (Tg) of preferably from -10 ° C. ~ 70 ° C., and more preferably from -5 ℃ ~ 50 ℃.
[0041]
　Further, the antistatic layer 111, other than the above may contain various additives that generally used for coating film. Such additives include, for example can be mentioned various pigments, it is also possible to add various titanium oxide used as a general white pigment. In this case, so as not to conflict with the conditions of the titanium oxide to function as an antistatic agent as described above, it is preferable to select the titanium oxide used as a pigment.
[0042]
　Titanium oxide 113 having a specific acicular shape as described above, by being contained in the antistatic layer 111 in a content as described above, titanium oxide 113 having a needle-like shape, schematically in Figure 3 as shown in, it will be present in the antistatic layer 111 each other in contact with each other. Titanium oxide 113 according to this embodiment, since the average length L becomes sufficiently larger shape than the average thickness D, a minor axis direction of thickness of the antistatic layer 111 of titanium oxide 113 (i.e. Z-axis direction ) and substantially parallel, the presence proportion of those long axis of titanium oxide 113 lying increases.
[0043]
　The thickness of the antistatic layer 111 (shown in FIG. 3, Z-axis direction thickness) d of preferably a 2 [mu] m ~ 30 [mu] m. When the thickness d of the antistatic layer 111 is less than 2μm can not antistatic layer 111 exhibits sufficient conductivity, the dust or the like adhering to the outermost surface of the coated metal plate according to the present embodiment there is a possibility that it becomes difficult to reliably suppressed. Further, when the thickness d of the antistatic layer 111 is 30μm exceeded, the existence probability of that the long axis of the titanium oxide 113 is parallel to the Z-axis direction, becomes high. In this case, charges located on the Z-axis positive direction side of the surface of the antistatic layer 111 is transmitted to the longitudinal axis of the titanium oxide 113, is more likely to continue to move in the thickness direction of the antistatic layer 111, the charge throughout the plane of the barrier layer 111 (the entire XY plane), it may be difficult to achieve conductivity.
[0044]
　The thickness d of the antistatic layer 111 that is 2 [mu] m ~ 30 [mu] m, as schematically shown in FIG. 3, the long axis is the surface normal direction of the metal plate of titanium oxide 113 having a needle-like shape (i.e. Z-axis sufficiently inclined with respect to) the long axis of the titanium oxide 113 can be more enhanced rate that is substantially parallel to the XY plane. In this case, a sufficient inclination, the long axis is the Z axis of the titanium oxide 113 (i.e., the thickness direction of the antistatic layer 111) 45 degrees or more with respect, preferably means having a tilt angle of 60 degrees or more . As a result, charges located on the Z-axis positive direction side of the surface of the antistatic layer 111 is transmitted to the longitudinal axis of the titanium oxide 113, can continue to move the antistatic layer 111 in the horizontal direction becomes higher throughout the plane of the antistatic layer 111 (the entire XY plane), it is possible to achieve a more uniform conductivity. When the presence ratio of those long axis of titanium oxide 113 is inclined with respect to the surface normal direction of the metal plate, it is more than 95% of the number of titanium oxide 113 included in the antistatic layer 111, uniform conductive the preferred is easily obtained. Here, the upper limit value of the existing ratio is not particularly defined, it may be 100%. The thickness d of such antistatic layer 111, more preferably from 3 [mu] m ~ 25 [mu] m, more preferably 5 [mu] m ~ 20 [mu] m.
[0045]
　Incidentally, in the antistatic layer 111, the existing ratio of those long axis of titanium oxide 113 is inclined with respect to the surface normal direction of the metal plate, in a cross section of the antistatic layer 111, oxide is focused Titanium 113 it can be regarded as existing proportion. Such existence ratio is, for example, the cross section of the antistatic layer 111 microscopic observation at a magnification of about 1,000 times, and the number of titanium oxide 113 contained in field of view, and the number of those of which the long axis is inclined, it can be calculated by counting. In this case, a plurality of field of view (e.g., 10 about the field of view) an average of the existence ratio of the long axis of the antistatic layer 111 is the abundance ratio of the titanium oxide 113 inclined with respect to the surface normal direction of the metal plate it is preferable.
[0046]
　The thickness d of the antistatic layer 111, for example, the case of forming an antistatic layer 111 by a roll coater, by controlling the peripheral speed and roll pressure conditions of each roll, be controlled to an appropriate value possible it is. Further, in the case of ex-post measuring the thickness d of the antistatic layer 111, it is possible to use a known method can be used for example, the following method. That may be used measurement by cross-sectional observation of the antistatic layer 111 is not particularly restricted but includes the method, it may be utilized the above-described method and the like.
[0047]
　Note that in the interior of the antistatic layer 111, is either titanium oxide 113 having a needle-like shape is how to present, for example, using an electron microscope or the like, can be confirmed by the following method . That may be used a method similar to check an average length L and average diameter D of titanium oxide 113 ex post facto.
[0048]
　When the antistatic layer 111 according to this embodiment, as measured in its surface resistivity (i.e., Z-axis positive direction resistance at the surface of that shown in FIG. 3) Static Honest Meter (Static Honest Meter), the surface resistance × 10 1 13 is preferably a value of less Omega. Antistatic layer 111 × 10 1 13 to have a surface resistance of less Omega, the surface charge on the surface of the antistatic layer 111, it is possible to conduct further efficiently. The lower limit of the surface resistance, the smaller well, particularly not intended to define, 1 × 10 6 to the Omega or less, because accompanied by various difficulties, 1 × 10 6 Omega is substantially the lower limit value. The surface resistance of the antistatic layer 111, more preferably, 1 × 10 6 Omega ~ 1 × 10 10 is Omega.
[0049]
　Antistatic layer 111 according to this embodiment, the light transmission attenuation at a wavelength of 555nm is not more than 5%. Here, the transmittance attenuation factor, as illustrated in FIG. 3, the light incident on the antistatic layer 111, antistatic layer 111 passes through the lower side of the antistatic layer 111 (Z-axis negative direction when reflected back by the end surface of) shows the percentage of light that is absorbed by the antistatic layer 111. Here, the human eye, although individual differences are, can be sensitive to light of a wavelength of 380 nm ~ 780 nm, the peak of the sensitivity is in the vicinity of a wavelength of 555 nm. Therefore, by the light of the transmission attenuation at a wavelength of 555nm is not more than 5% the human eye, when the visible light is transmitted through the antistatic layer 111, made to feel a scarcely attenuated. By antistatic layer 111 according to this embodiment has a transmission attenuation factor as described above, such antistatic layer 111, for example highly reflective coated metal plate as disclosed in Patent Document 1 and Patent Document 2 even when applied to, it does not significantly compromise the high reflectivity with a high reflection coated metal plate. Transmittance attenuation rate of light of wavelength 555nm is preferably 3% or less.
[0050]
　Above with reference to FIGS. 3-4, the antistatic layer 111 according to the present embodiment has been described in detail.
[0051]
[For coating film layer]
　Subsequently, referring to FIGS. 5 to 8, the coating film layer 103 comprising an antistatic layer 111 as described above, will be described in detail.
[0052]
　As with prior mentioned coating film layer 103 according to the present embodiment is composed of one or more layers. Therefore, as schematically shown in FIG. 5, the coating film layer 103 may be composed of only the antistatic layer 111. In this case, antistatic layer 111 according to this embodiment, is to be positioned directly above the at least one surface of the metal plate 101.
[0053]
　As described with reference to FIG. 3, etc., antistatic layer 111 according to this embodiment includes a titanium oxide 113 having a needle-like shape, at least in part, the major axis of the antistatic layer of the titanium oxide 113 111 lying horizontal. Accordingly, as shown in FIG. 5, the ends of the antistatic layer 111 (e.g., at least one end of the X-axis direction) Grounding, charge present on the surface of the antistatic layer 111, needle while being conducted by the titanium oxide 113 having a shape to move inside the antistatic layer 111 in the horizontal direction. As a result, the surface electric charge generated on the surface of the antistatic layer 111 is as escapes to the outside from the X-axis direction of the end portion of the antistatic layer 111. Accordingly, the antistatic layer 111 according to the present embodiment, to prevent dust from adhering to the surface of the antistatic layer 111, it is possible to realize a 耐埃 adhesion.
[0054]
　Further, the coating film layer 103 according to this embodiment may include a plurality of layers. In this case, antistatic layer 111 according to this embodiment, as schematically shown in FIG. 7, it is preferably located in the outermost layer of the coating film layer 103. In this case, the 121 (a layer located on the Z-axis negative direction side) lower the antistatic layer 111 is not particularly defined.
[0055]
　Further, the coating film layer 103 according to this embodiment is composed of a plurality of layers, and antistatic layer 111 is also considered if it does not exist in the outermost layer of the coating film layer 103. In this case, as schematically shown in FIG. 8, 123 (the layer positioned on the Z-axis positive direction side) layer of the antistatic layer 111 is preferably a layer having conductivity. Such conductive upper layer 123 having a by forming over the antistatic layer 111, by conducting efficiently the surface charge generated in the outermost layer to the antistatic layer 111 of the coating film layer 103, antistatic layer 111 it is the X-axis direction of the end portion can be released to the outside. Even when, as shown in FIG. 8, the insulating layer 107 between the metal plate 101 and the coating film layer 103 may also be present, of course.
[0056]
　Here, either one layer or a plurality of layers constituting the coating film layer 103 according to the present embodiment, the average particle diameter of the white paint is contained containing titanium oxide of 200 nm ~ 400 nm. Layer the white paint is contained may be a antistatic layer 111 as described above, may be a layer other than the antistatic layer 111. Antistatic layer 111 has a transmittance attenuation factor as described above, and either one layer or a plurality of layers constituting the coating film layer 103, white paint having an average particle diameter containing titanium oxide of 200 nm ~ 400 nm is by being contained, coating film layer 103 according to the present embodiment functions as a highly reflective coating layer having a total light reflectance of 85% or more, the total light reflectance of the coated metal plate 10 according to this embodiment consisting of 85% or more. Here, the total light reflectance as described above, preferably not less 87.5% or more, more preferably 90% or more. The upper limit of such total light reflectance is not particularly specified, the value is the higher the better.
[0057]
　The content of titanium oxide having an average particle size of 200 nm-400 nm is can be selected as needed, based on the solids content in the layer to be contained, and 30 wt% to 60 wt% it is preferable to. When the content is less than 30% by mass, the total light reflectance of the coated metal plate 10 may become less than 85%. When the content is 60 mass% excess, the workability of the coated metal plate 10 may be reduced. Further, since the most total light reflectance content of titanium oxide having an average particle size of 200 nm ~ 400 nm by 50 weight% is increased, more preferred.
[0058]
　As the titanium oxide having an average particle size of 200 nm ~ 400 nm, generally pigments are available as a white pigment, for example, it is possible to use either the titanium oxide "Tipaque" series manufactured by Ishihara Sangyo Kaisha Ltd..
[0059]
　Above with reference to FIGS. 5 to 8, the coating film layer 103 comprising an antistatic layer 111, has been described in detail.
[0060]
Modification of the antistatic layer]
　Next, referring to FIG. 9, a modified example of the antistatic layer 111 according to the present embodiment will be briefly described.
[0061]
　In the example shown in FIG. 3 or the like, the case where the antistatic layer 111 is formed of one layer, antistatic layer 111 according to this embodiment may be composed of two or more multiple layers. In this case, as schematically shown in FIG. 9, as the antistatic layer positioned on the outermost layer side of the coated metal plate 10, it is preferable that the concentration of the titanium oxide 113 is high is antistatic agent . In the example shown in FIG. 9, the concentration of the antistatic layer 111a side as titanium oxide 113 is high, the concentration of the antistatic layer 111c side as titanium oxide 113 is lowered. By providing a concentration gradient of such titanium oxide 113, it is possible to surface concentrated titanium oxide 113, it is possible to express more efficiently antistatic property at a content of less titanium oxide 113 .
[0062]
[Insulating layer]
　such as prior description, it is an insulating layer 107 which may provided between the metal plate 101 and the coating film layer 103, as such an insulating layer 107, are disclosed in Patent Documents 1 and 2 like being, it may be provided with a highly reflective coating layer having a total light reflectance of 90% or more. High-reflection coating layer as disclosed in Patent Document 1 and Patent Document 2, since functions as an insulating layer, by providing such a high-reflective coating layer as the insulating layer 107, coated metal sheet the light incident on the 10 is reflected at a high reflectivity of 85% or more, and can be realized without the dust from adhering to the outermost layer-coated metal sheet.
[0063]
　Further, a highly reflective coating layer as disclosed in Patent Document 1 and Patent Document 2 in terms of forming the insulating layer 107, coated metal plate 10 formed of the coating film layer 103 according to this embodiment , for example, JIS K 5600-5-1 (such standard is a standard that corresponds to ISO1519.) at 3T bending test at 20 ° C. conforming to, that peeling of the film does not exist for superior processability it becomes possible.
[0064]
　The metal plate 101 and the insulating layer 107 according to the present embodiment, using a highly reflective coated metal plate as disclosed in Patent Document 1 and Patent Document 2, the outermost layer of such a highly reflective coated metal plate, it may be formed coating film layer 103 according to the present embodiment it is needless to say.
[0065]
　Further, as the insulating layer 107 according to the present embodiment, when forming the high-reflection coating layer as disclosed in Patent Document 1 and Patent Document 2, for such high-reflection coating layer, prior description were such needles titanium oxide 113 having a shape further added, it may be realized a highly reflective coating layer which functions as an antistatic layer 111.
[0066]
　Above with reference to FIGS. 1-9, the coated metal sheet 10 according to this embodiment has been described in detail.
[0067]

　Next, a method of manufacturing the coated metal plate 10 according to the present embodiment will be briefly described.
　Coated metal plate 10 according to the present embodiment prepares a predetermined metal plate 101, metal after forming as required a desired layer 105 on the metal plate 101, the coating material for forming the antistatic layer 111 applied to the surface of the plate 101, and dried and solidified, it is possible to produce.
[0068]
　Here, the paint for forming the antistatic layer 111 can be prepared with reference to the known methods. That is, water or various organic solvents was prepared as a solvent, in such a solvent, the titanium oxide having a needle-like shape as described above, by incorporating the various binder resin, thereby forming an antistatic layer 111 it may be used as the paint for.
[0069]
　Here, also for the organic solvent used as a solvent, it is not particularly limited, toluene, organic solvents hydrocarbons xylene; ketone, methyl isobutyl ketone, cyclohexanone, ketone organic solvents and isophorone; ethyl acetate, butyl, ester organic solvents such as ethylene glycol monoethyl ether acetate; methanol, alcoholic organic solvents such as ethanol, ethylene glycol monoethyl ether, ether alcohol-based organic solvents such as diethylene glycol monobutyl ether; if combined as appropriate for use, etc. good.
[0070]
　In the case of forming a plurality of layers including an antistatic layer 111 on the metal plate 101, as is commonly done, for each of a plurality of layers, by performing repeatedly the coating and drying and baking, the coated metal plate 10 it may be formed. However, applying a coating material for forming the various layers, and a coating material for forming the antistatic layer 111, using a multilayer simultaneous coating or wet-on-wet method, a part or the whole of the surface of the metal plate 101 Write is prepared by the performance surface of each layer, from the viewpoint of workability and productivity.
[0071]
　Here, the multilayer simultaneous coating and the slot die coater or a slide hopper type curtain coater device capable of discharging to stack different paint from parallel two or more slits such as a plurality of coating solution at the same time applied to the substrate in a stacked state, it is the laminated coating solution simultaneously method of drying and baking.
[0072]
　In addition, the wet-on-wet coating, after coating the coating liquid on a time base, before the coating solution dries wet state, further applying another coating liquid thereon, the laminated multilayer coating liquid is simultaneously drying and baking process for. Specifically, as a method for wet-on-wet coating, for example, a roll coater, a dip, curtain flow coater, by coating methods such as roller curtain coater, after painting coating layer 1 layer, dry baking the coating layer before further thereon, a curtain flow coater, roller curtain coater, a slide hopper type curtain coater, after painted in the second layer in a manner that can be painted substrate and a non-contact such as a slot die coater, stacked and a method for simultaneously drying baked multilayer coating film in the wet state and the like.
[0073]
　In the present embodiment, a multilayer simultaneous coating, or as a method of baking a wet-on-wet coating coating film simultaneously, generally baking furnace known coatings, for example, hot air drying oven, direct flame type heating furnace, induction furnace, infrared furnace, or, it may employ a combination furnace or the like.
[0074]
　Thus, by simultaneously applying and laminating a coating solution of undried, by coating solution of each layer mix slightly at the boundary portion of the coating liquid, to control the slight irregularities at the interface of each layer becomes possible, it is possible to workability as better by enhancing the adhesion of each layer by the anchor effect of the irregularities. Further, since performing the conventional collectively drying process which has been performed for each layer, it is advantageous in terms of productivity and production costs, further, there is also advantage that drying equipment is less.
[0075]
　Although the method of manufacturing the coated metal plate 10 according to the present embodiment has been briefly described.
Example
[0076]
　Hereinafter, while showing Examples and Comparative Examples, the coated metal plate according to the present invention will be specifically described. Incidentally, embodiments described below, merely only one example of a coated metal plate according to the present invention, coated metal plate according to the present invention is not limited to the following examples.
[0077]
[Base metal plate]
　In order to confirm the performance of the coated metal plate according to the present invention, a metal plate such as shown below, and a substrate metal plate coated metal plate according to the present invention. The type of the metal plate used is shown in Table 1 below. Incidentally, the base material of the metal plate plated, plate thickness using the mild steel plate of 0.5 mm. Similarly, the thickness of the SUS plate base material used was a 0.5 mm. These metal plates, the surface alkali degreasing treatment was used as washed with water and dried.
[0078]
[Table 1]

[0079]
[Chemical conversion layer]
　The silane coupling agent 5 g / l, to prepare an aqueous solution containing a water-dispersed silica 1 g / l and an aqueous acrylic resin 25 g / l, and a chemical conversion treatment agent. Note that the silane coupling agent, .gamma.-glycidoxypropyltrimethoxysilane with trimethoxysilane, the water-dispersed silica is used SNOWTEX N type manufactured by Nissan Chemical Industries, polyacrylic acid in an aqueous acrylic resin Using. To the surface of the base metal plate, 100 mg / m 2 of the above chemical conversion treatment agent so that the amount of deposition of a roll coater, followed by drying under the conditions of the reaching plate temperature 60 ° C., the preliminary chemical conversion layer It was allowed to form.
[0080]
[Undercoating film layer]
　The coating composition for forming the undercoating film layer prepares a commercial primer coating is a Nippon Fine Coatings Co. FL641EU primer clear coating, to such paints, tripolyphosphate in aluminum dihydrogen (Tayca Co. K-WHITE # 105) and the calcium ion exchange silica (GRACE Co. SHIELDEX C303) the mass ratio of 1: was added 15% by weight, based on the solid content in a mixing ratio of 1 It was prepared by stirring at paint disperser. The upper layer of the underlying chemical conversion layer, the primer coating was applied by a roll coater to a predetermined dry film thickness, peak metal temperature of the metal plate is heated and dried under conditions such that a 210 ° C., an undercoat coating layer It was formed.
[0081]
[Top coating layer]
　The coating composition for forming a top coating film layer, as a binder resin, non-crystalline polyester resin (Toyobo Co., Ltd. Byron (TM) 630, number-average molecular weight: 23 × 10 3 a glass transition temperature of the 7 ° C.), with Esso Sekiyu KK Solvesso 150 (trade name) and cyclohexanone weight ratio of 1: is dissolved in a first organic solvent in a mixing ratio of melamine resin curing agent as a complete alkyl type methylated melamine resin (manufactured by Mitsui Cytec Co., Ltd. Cymel (TM) 303), it was added 15 wt% of the polyester resin solid content, as a reaction catalyst, Mitsui Cytec Co. catalyst 6003B It was added 0.5 wt% (trade name) with respect to the total resin solids, optionally further adding a pigment shown in Table 2 below, stirring child with paint disperser It was prepared with. The upper layer of the undercoating film, a roll coater so that the top coating to a predetermined thickness, and heated and dried under conditions peak metal temperature of the metal plate is 230 ° C., forming a top coating film layer 1 It was.
[0082]
[Pigment]
　The pigment to be added to the top coat was determined by taking an electron microphotograph of the pigment, the samples each in the resulting image by performing the measurement, the average was calculated for the obtained measurements. Specifically, the 100 or so of the titanium oxide arbitrarily selected from the obtained image, by calculating the length and thickness were respectively measured, the average value of the obtained measurement values, respectively, the average length It was and average thickness. If necessary, adjust the pigment size by classifying the pigment, was used pigment after adjustment. In Table 2 below, the pigment shown in B3 ~ B6, B9 is a titanium oxide which functions as titanium oxide needle-shaped in accordance with the present invention. B1 is used as a general white pigment is titanium oxide which does not have a conductive layer, the average particle diameter is as shown in Table 2 below. B2, B7 ~ B8, B10 is a titanium oxide used as outside the specified functional pigment of the present invention. Further, B11 is a powder conductive material consisting of aluminum-doped zinc oxide, the average particle diameter is as shown in Table 2 below. The average particle size of the pigment in B1 and B11 shown in Table 2 below, respectively catalog value. As in Comparative Example 1 to be described later, by including the addition amount shown titanium oxide corresponding to B1 in Table 3 below, topcoat layer containing titanium oxide corresponding to B1, the table 4 below the function as highly reflective coating layer having a total light reflectance of 90% or more as shown in.
[0083]
　In Table 2 below, Ishihara Sangyo Kaisha Ltd. FT series and FS Series, titanium oxide Otsuka Chemical Co. WK-500 series, SnO Sb-doped 2 is surface coated acicular shape it is a titanium oxide.
[0084]
[Table 2]

[0085]
[1 Sonurimakuso]
　If necessary, the upper layer of the underlying chemical conversion layer, a roll coater so that only the top coating to a predetermined thickness, and 230 ° C. peak metal temperature of the metal sheet dried by heating it becomes conditions to form a coating layer made of one layer of top coating layer 1.
[0086]
[3 Sonurimakuso]
　If necessary, the upper layer of the underlying chemical conversion layer, the further layer of the coated metal plate obtained by laminating the primer coating and the top coating, the top coating a predetermined thickness of a roll coater so that, peak metal temperature of the metal plate is heated and dried under conditions such that a 230 ° C., undercoat layer, topcoat layer 1, and consists of three layers of top coating layer 2 the coating layer was formed.
[0087]
　Also, among the 3 Sonurimakuso, a "top coating layer 1" and two layers of "top coating layer 2", and simultaneous coating by a curtain flow coater, peak metal temperature of the metal plate is 230 ° C. and dried by heating under the conditions, undercoating film layer, "top coating layer 1", and to form a coating layer composed of three layers of "top coating layer 2 '.
[0088]
[NurimakusoAtsu]
　a coated metal plate fabricated in a thickness direction perpendicular of the coating layer, embedded in a room temperature drying type epoxy resins, the embedded surface after mechanical polishing and observed by SEM. Then, the cross-sectional image of the resulting coated metal plate was measured thickness of the coating layer.
[0089]
　Incidentally, was observed together state of titanium oxide acicular shapes included in the coating layer, in all the coated metal plate produced, titanium oxide having 95% or more needle-like shape, the major axis, be inclined relative to the surface normal direction of the metal plate was confirmed in a state as schematically shown in FIG. Note that the presence proportion of those long axis of titanium oxide having a needle-like shape are inclined with respect to the surface normal direction of the metal plate, and is obtained by calculation with reference to the above-described method.
[0090]
　The coated metal plate produced, are summarized in Table 3.
[0091]
[table 3]

[0092]
[Table 4]

[0093]
　For coated metal plate shown in Table 3 was carried out the following evaluation tests. Note that none of the test, was evaluated surface the coating layer coated side.
[0094]
[Surface resistivity]
　The surface resistivity of the coated metal plate produced was measured using a static Honest Meter (Toa Telecommunications Ltd. SME-8310). The measurements immediately after application of a voltage 500V 60 seconds coated metal plate as the surface resistance value was evaluated surface resistance on the following criteria. In the following criteria, the evaluation value of 3 or more, effect on the surface resistance is confirmed. Further, with respect to the surface resistance was more stable evaluation value effect is obtained 4 or more.
[0095]
　　5: surface resistivity 1 × 10 9 Omega following
　　4: surface resistivity 1 × 10 9 Omega exceeded, 1 × 10 11 Omega following
　　3: surface resistivity 1 × 10 11 Omega exceeded, 1 × 10 13 Omega less
　　2: surface resistivity 1 × 10 13 Omega exceeded, 1 × 10 15 Omega follows
　　1: surface resistivity 1 × 10 15 Omega exceeded
[0096]
[耐埃adhesion]
　The coated metal plate fabricated, installed copier in an office in the wall of the rear upper 30cm position of (Fuji Xerox ApeosPort C5540 I), with respect to the ground on which grounded top coating layer and paste at an angle of 90 ° Te and indoor exposure, were recovered after the time of 6 months menstruation. Then, the reflectance of the coated metal plate before and after the exposure was measured in the same manner as in the measurement method of the reflectance was evaluated耐埃adhesion to the following criteria. In the following criteria, the evaluation value 2 or more, the effect is confirmed about耐埃adhesion. With respect耐埃adhesion was more stable evaluation value effect is obtained 3 or more.
[0097]
　　5: before and after exposure of the reflectance change is less than 1.0%
　　4: before and after exposure of the change of reflectivity of 1.0% or more, less than 1.5%
　　3: reflectance change before and after exposure of 1.5% or more, 2 less than 2.0%
　　2: exposure reflectance change before and after 2.0% or more, less than 2.5%
　　1: reflectance change before and after exposure to 2.5% or more
[0098]
[Workability]
　The coated metal plate produced, with reference to JIS K 5600-5-1, was 180 ° C. bending test. 180 ° C. bending test of coated metal plate is sandwiched state (respectively between the coated metal plate of any number at 20 ° C., bending 1T For one, the two bending 2T, 3 sheets bending 3T, 4 Like bending 4T, 5 sheets 5T bending, carried out in designated.) and, then, to observe the peeling existence of the coating film after the forced peeling tape the 180 ° C. bent portion, workability by the following criteria It was evaluated. In the following criteria, and the acceptance evaluation value of 3 or more.
[0099]
　　5: 1T bending, peeling is not in the coating film
　　4: bending 1T, it is peeled off the coating, the 2T bending, there is no peeling of the coating film
　　3: 2T bending, there is a delamination of the coating film, 3T bending, the release is not in the coating film
　　2: bending 3T, it is peeled off the coating, the 4T bending, there is no peeling of the coating film
　　1: 4T bending, some peeling of the coating film
[0100]
[Reflectivity]
　fabricated total light reflectance of the coated metal sheet (hereinafter, referred to as "reflectance".) The spectrophotometer was used as a reference plate that compacted barium sulfate powder (manufactured by Shimadzu UV- It was measured in an integrating sphere of 2600). It was then evaluated the reflectance on the following criteria. In the following criteria, the evaluation value of 3 or more, and the preferred level for applications such as reflectance is desired.
[0101]
　　5: reflectivity 90.0% or more to less than 92.5%
　　4: reflectance of 87.5% or more to less than 90.0%
　　3: reflectance of 85.0% or more and less than 87.5%
　　2: reflectivity 80.0% or more to less than 85.0%
　　1: reflectance is less than 80.0%
[0102]
　The results of evaluation of the coated metal plate produced, are summarized in Table 4 below.
[0103]
[table 5]

[0104]
[Table 6]

[0105]
　Table 4 Evaluation As apparent from the results summarized, coated metal plate according to the present invention, excellent surface resistivity, indicate the 耐埃 adhesion and processability, together with titanium oxide, which is known as a general white pigment doing, to obtain a coated metal plate having both an evaluation value 3 or more reflectivity. On the other hand, the coated metal plate as a comparative example, it was not having both excellent surface resistivity, reflectance and processability.
[0106]
　Having described in detail preferred embodiments of the present invention with reference to the accompanying drawings, the present invention is not limited to such an example. It would be appreciated by those skilled in the relevant field of technology of the present invention, within the scope of the technical idea described in the claims, it is intended to cover various changes and modifications , also such modifications are intended to fall within the technical scope of the present invention.
DESCRIPTION OF SYMBOLS
[0107]
　　10 coated metal plate
　101 the metal plate
　103 coating film layer
　107 insulating layer
　111 antistatic layer
　of titanium oxide of 113 acicular shape

claims

Located above the at least one surface of the metal plate, comprises a coating layer comprising one or more layers,
　the coating layer consisting of the one or more layers, the average length is 1 [mu] m ~ 10 [mu] m, and the average a is 0.1 [mu] m ~ 0.5 [mu] m thickness, the antistatic layer containing titanium oxide as an antistatic agent of a needle-like shape whose surface is coated with a conductive layer having conductivity, having at least one layer cage,
　any one or more layers of said coating layer contains a white paint average particle diameter containing titanium oxide of 200 nm ~ 400 nm,
　the content of the antistatic agent in the antistatic layer, wherein with respect to the total solid content of the antistatic layer is 5 mass% to 30 mass%,
　the total light reflectance is 85% or more, coated metal plate.
[Requested item 2]
　The surface resistance of the antistatic layer, 1 × 10 13 or less Omega, coated metal plate according to claim 1.
[Requested item 3]
　The thickness of the antistatic layer is 2 [mu] m ~ 30 [mu] m, coated metal plate according to claim 1 or 2.
[Requested item 4]
　In the antistatic layer, the presence proportion of those long axis of the titanium oxide is inclined with respect to the surface normal direction of the metal plate having the needle-like shape, the number of titanium oxide antistatic layer contains 95 at least%, coated metal sheet according to any one of claims 1 to 3.
[Requested item 5]
　Between the metal plate and the coating layer further comprises an insulating layer, coated metal sheet according to any one of claims 1 to 4.
[Requested item 6]
　The antistatic layer is located as the outermost layer of the coated metal plate, coated metal sheet according to any one of claims 1 to 5.
[Requested item 7]
　The coating layer is composed of a plurality of layers,
　a layer located further surface layer side than the antistatic layer of said coating layer is a layer having conductivity, in any one of claims 1 to 5, coated metal sheet according.
[Requested item 8]
　The antistatic layer is composed of a plurality of layers,
　the more the antistatic layer located on a surface layer side, the density of the antistatic agent is high, coated metal sheet according to any one of claims 1 to 7.