Technical field
[0001]
　The present disclosure relates to a Sn-plated steel sheet.
BACKGROUND
[0002]
　Tin (Sn) plated steel sheet is better known as "tinplate", the can use other such beverage cans and food cans, it is widely used. This is because Sn is safe to the human body, and a beautiful metallic. The Sn plated steel sheet is mainly produced by electroplating. This is controlled with the amount of necessary minimum amount of Sn is a relatively expensive metal is by electroplating method than hot-dip plating method is preferred. Sn-plated steel sheet after plating, or, after a beautiful metallic luster imparted by heating and melting treatment after plating, the chromate treatment with a solution of hexavalent chromate (electrolysis treatment, immersion treatment, etc.), Sn chromate film to plated layer is often subjected. The effect of the chromate film, prevents the appearance yellowing by suppressing the oxidation of the surface of the Sn plating layer, prevention of coating adhesion deterioration by cohesive failure of the tin oxide in the case where used is painted, sulfidation blackening improvements, and the like.
[0003]
　On the other hand, in recent years, from growing awareness of the environment and safety, not only does not contain hexavalent chromium in the final product, it is required not to perform chromate treatment itself. However, Sn-plated steel sheet is not chromate film, as described above, the appearance by the growth of tin oxide yellowing or paint adhesion is lowered. Further, it decreases the sulfidation blackening.
[0004]
　Therefore, Sn-plated steel sheet in which the coating process to replace the chromate film have been proposed.
[0005]
　For example, Patent Document 1 below, by treatment with a solution containing a phosphoric acid ion and a silane coupling agent, Sn-plated steel sheet has been proposed to form a film containing P and Si.
　Patent Document 2 below, by treatment with a solution containing aluminum phosphate, Al and P, Ni, and at least one Co and Cu, to form a coating comprising the reaction product of a silane coupling agent Sn-plated steel sheet has been proposed.
　Patent Document 3 below, subjected to heat treatment to Zn alone plated layer disappears after the Zn plated on Sn plating method of the Sn-plated steel sheet having no chromate film have been proposed.
　Patent Document 4 and Patent Document 5 below, zirconium, phosphate and container steel sheet having a chemical conversion film containing phenol resin have been proposed.
　In the following Patent Document 6, a Sn plating layer, after Sn plating layer formed, in a phosphate aqueous solution, cathodic electrolysis treatment and then formed by performing an anodic electrolysis treatment, chemical conversion comprising tin oxide and tin phosphate Sn-plated steel sheet having a treated layer has been proposed.
　In the following Patent Document 7, tin oxide, and, Zr, is Sn-plated steel sheet with a coating containing Ti and P have been proposed. Patent Document 6, when forming a film, it is proposed to be carried out alternating electrolysis performed alternately a cathode electrolytic treatment and anodic electrolysis.
[0006]
Patent Document 1: JP 2004-60052 JP
Patent Document 2: JP 2011-174172 Patent Publication
Patent Document 3: JP 63-290292 Patent Publication
Patent Document 4: JP 2007-284789 Patent Publication
Patent Document 5: JP open 2010-13728 JP
Patent Document 6: JP 2009-249691 Patent Publication
Patent Document 7: WO 2015/001598
[0007]
Non-Patent Document 1: Surface Science Society of Japan, ed., "Surface analytical chemistry book selection X-ray photoelectron spectroscopy", Maruzen Co., Ltd., P. 83
Summary of the Invention
Problems that the Invention is to Solve
[0008]
　However, the Sn plated steel sheet and a manufacturing method proposed in the above Patent Documents 1 to 7 can not be sufficiently suppressed the growth of tin oxide over time, yellowing resistance, paint adhesion, and there is a problem of poor sulfidation blackening.
[0009]
　An object of one aspect of the present disclosure has been made in view of the above problems, without the conventional chromate treatment, yellowing resistance, paint adhesion, and, more excellent in sulfidation blackening Sn It is to provide a plated steel sheet.
Means for Solving the Problems
[0010]
　The means for solving the above problems includes the following aspects.
[0011]
(1) and the steel plate,
　is formed on at least one surface of said steel sheet contains, by mass%, the metal Sn 0.1 g / m 2 or more 15 g / m 2 and the Sn plating layer containing less,
　is formed on a surface of the Sn plated layer , and the film layer containing the zirconium oxide and tin oxide,
　have,
　the content of the zirconium oxide in the coating layer is a metal Zr content 0.2 mg / m 2 or more 50 mg / m 2 or less There, Sn3d
　by X-ray photoelectron spectroscopy of the tin oxide in the coating layer 5/2 peak position of the binding energy is greater than 1.6eV than the peak position of the binding energy of metals Sn, Sn-plated steel sheet.
(2) thickness of the coating layer is at 2nm or 100nm or less, Sn-plated steel sheet according to (1).
(3) the coating layer, the mass ratio per unit area, further contains phosphorus P amount / metal Zr amount is 0.2 or more and 1 or less, Sn-plated steel sheet according to (1) or (2) .
Effect of the invention
[0012]
　According to one aspect of the present disclosure as described above, without performing conventional chromate treatment, yellowing resistance, paint adhesion, and, can provide a more excellent Sn-plated steel sheet by sulfidation blackening to become.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013]
FIG. 1 is a diagram of an example of an element concentration profile in the thickness direction of the Sn plated layer and the coating layer of the Sn plated steel sheet of the present disclosure (the depth direction).
DESCRIPTION OF THE INVENTION
[0014]
　It is described in detail below the present disclosure.
　In the present specification, the numerical range expressed using "to" means a range including numerical values described before and after "to" as the lower and upper limits.
　As used herein, the term "process" not only separate steps, if even that can not be clearly distinguished from other processes intended purpose of the process is achieved, the term include.
　As used herein, the term "steel sheet" refers to a base steel of the target (so-called plated original plate) to form a Sn plated layer and the coating layer.
[0015]
　The present disclosure described below, food cans, and Sn plated steel sheet is widely used in other cans applications such as beverage cans, to a method of manufacturing such a Sn-plated steel sheet. More specifically, without performing the conventional chromate treatment, yellowing resistance, paint adhesion, and a process for producing a more excellent Sn plated steel sheet and Sn-plated steel sheet by sulfidation blackening.
[0016]
　Specifically, Sn-plated steel sheet of the present disclosure, and the steel plate, is formed on at least one surface of said steel sheet contains, by mass%, the metal Sn 0.1 g / m 2 or more 15 g / m 2 and the Sn plating layer containing less , formed on the surface of the Sn plated layer has a, and the film layer containing the zirconium oxide and tin oxide.
[0017]
　More particularly, the present disclosure Sn-plated steel sheet, Sn-plated layer, by mass%, the metal Sn 0.1 g / m 2 or more 15 g / m 2 containing less.
　The content of zirconium oxide in the coating layer is per side 0.2 mg / m of a metal Zr content 2 or 50 mg / m 2 or less.
　X-ray photoelectron spectroscopy of the tin oxide in the coating layer: (XPS X-ray Photoelectron Spectroscopy ) by Sn3d 5/2 peak position of the binding energy is greater than 1.6eV than the peak position of the binding energy of metals Sn.
[0018]

　steel sheet, it is not particularly defined, as long as the steel sheet used in the Sn-plated steel sheet of a typical container, it is possible to use any one. Steel sheet, for example, low carbon steel, and the like ultra low carbon steel. The manufacturing method and the material of the steel sheet not particularly defined, for example, hot from the casting and rolling, pickling, cold rolling, annealing, temper steel sheet manufactured through the steps of rolling and the like,
[0019]

　at least one surface of the steel sheet, and Sn-plated, Sn plating layer is formed. The Sn plating layer, the corrosion resistance of the steel sheet is improved. Note that the "Sn-plated layer" herein not only Sn plating layer of Sn metal alone, including Sn-plated layer containing at least one of the trace elements other than metal Sn and metal Sn and impurities.
[0020]
　Sn plating layer, by mass%, the metal Sn 0.1 g / m 2 or more 15 g / m 2 containing less. In other words, the adhesion amount per one side of the Sn-plated layer, the amount of metal Sn (i.e. metal Sn equivalent amount) at 0.1 g / m 2 or more 15 g / m 2 or less. Adhesion amount per one side of the Sn-plated layer is 0.1 g / m of a metal Sn amount 2 when it is less than has poor corrosion resistance, undesirably. Further, the adhesion amount per one side of the Sn-plated layer is 15 g / m of a metal Sn amount 2 exceed the effect of improving the corrosion resistance of Sn metal is sufficient, a further increase is not preferable from the economical point of view. Further, there is a tendency to decrease even coating adhesion.
　Sn plating layer, by mass%, the metal Sn 1.0 g / m 2 or more 13 g / m 2 preferably contains less. In other words, the adhesion amount per one side of the Sn plating layer, 1.0 g / m of a metal Sn amount 2 or more 13 g / m 2 or less.
[0021]
　Here, the metal Sn of Sn plating layer (i.e., coating weight per one surface of the Sn-plated layer), for example, an electrolytic method described in JIS G 3303, or the measured value by the fluorescent X-ray method.
[0022]
　The metal Sn of Sn plating layer, ICP emission spectrometry, or GDS (glow discharge optical emission spectroscopy) may be measured by a calibration curve method using. In particular, a Sn-plated steel sheet coating layer on the Sn plated layer is formed, when measuring the metal Sn of Sn plating layer, a calibration curve method is suitable for using GDS (glow discharge optical emission spectroscopy).
[0023]
　Specifically, the measurement method by ICP emission spectrometry is as follows.
　First, no coating layer is formed on the Sn plating layer, to prepare a test piece of steel sheet which Sn plating layer is exposed (test piece only Sn plating layer is formed steel plate). By dipping the test piece in 10% nitric acid were dissolved Sn plating layer, Sn in the lysate obtained with ICP emission spectrometry (e.g., using Ar manufactured by Agilent Technologies 799Ce, the carrier gas.) determined by. Then, the intensity signal obtained by the analysis, a calibration curve concentration was prepared from the known solution, based on the formation area of the Sn-plated layer of the test piece to determine the metal Sn of Sn plating layer
[0024]
　The measurement method according to a calibration curve method using a GDS (glow discharge optical emission spectroscopy) is as follows.
　First, using the reference sample metal Sn of Sn plating layer is known, previously obtained relation between the intensity signals and the sputtering rate of the metal Sn of the Sn-plated layer of the reference sample by GDS while performing the sputtering, the calibration curve make.
　On the other hand, to prepare a test piece of steel sheet which is the film layer is formed on the Sn plating layer (Sn plated layer and film layer are sequentially formed steel plate of the test piece). From the surface of the coating layer of the test piece, while the sputtering was performed an analysis by GDS, measures the intensity signal of the metal Sn of Sn plating layer. Intensity signal obtained metal Sn, the sputtering rate, and a calibration curve prepared, obtaining the metal Sn of Sn plating layer.
　Here, Sn plating layer, the intensity signal of Zr is from the maximum value 1/2 consisting of the depth of the intensity signal of Zr, the intensity signal of Fe, becomes 1/2 of the maximum value of the intensity signals of Fe It is defined as a region of depth. Then, the average value of the metal Sn amount of the region, the metal Sn of Sn plating layer.
[0025]
　Method of applying a Sn-plated surface of the steel sheet is not particularly intended to define, for example, a known electroplating method is preferred. It is also possible to use a melt process for Sn plating by immersing the steel sheet in the molten Sn. The electroplating method, for example, can be utilized known Ferrostan bath, halogen bath, an electrolytic method using an alkali bath.
[0026]
　Incidentally, after Sn plating may be subjected to a heating and melting process of heating the steel sheet having a Sn plating layer 231.9 ° C. or higher, which is the melting point of Sn. This heating and melting treatment, along with gloss comes into the surface of the Sn-plated layer, between the Sn-plated layer and the steel sheet, alloy layer of Sn and Fe are formed, the corrosion resistance is further improved.
[0027]

　Sn-plated steel sheet of the present disclosure, the surface of the Sn-plated layer formed on the surface of the steel sheet, coating layers containing both tin oxide and zirconium oxide having.
　The content of zirconium oxide in the coating layer, the amount of metal Zr (i.e. metal Zr in terms of weight) in 0.2 mg / m 2 or more 50 mg / m 2 or less. The content of zirconium oxide in the coating layer is a zirconium content oxide per surface.
　Tin oxide in the coating layer is, Sn3d by XPS 5/2 peak position of the binding energy of a large tin oxide or 1.6eV than the peak position of the binding energy of metals Sn.
[0028]
　The above Sn3d 5/2 and, P. Non-Patent Document 1 As described in 83, showing the electron energy level in the Sn.
[0029]
Sn3d 　by XPS of the tin oxide 5/2 peak position of the binding energy of a peak position obtained by the surface of the coating layer was measured by XPS. However, the surface of the coating layer, further chemical conversion layer, if the layer of such coating layer is formed, after removing these layers, SiO by sputtering 2 film was depth 0.5 ~ 2 nm etching in terms of targeting surface of the layer, Sn3d by XPS 5/2 measures the peak position of the binding energy.
[0030]
　Here, Sn-plated steel sheet of the present disclosure, the surface of the Sn-plated layer, by having a coating layer of zirconium oxide as described above and a tin oxide coexist, yellowing resistance, paint adhesion, and, it can further improve the sulfidation blackening. Incidentally, the coating layer of only tin oxide, or, in the coating layer of zirconium oxide alone, yellowing resistance, paint adhesion, and can not sufficiently improve the sulfidation blackening. The reason for this is not clear, is believed to be as follows by a detailed investigation of the inventors of the present invention.
[0031]
　Conventionally, tin oxide to produce and grow on the surface of the Sn plating layer is different from the tin oxide of the present disclosure, Sn3d by XPS 5/2 1 than the peak position of the binding energy peak position Sn metal binding energy of. was found to be tin oxide is less than 6 eV. This is oxygen deficient, i.e. tin oxide (hereinafter, defined as "oxygen deficient tin oxide".) Having an oxygen vacancy and the estimated oxidation of the tin surface of the Sn plating layer proceeds with time, the oxygen deficient tin oxide is grown. On the other hand, Sn3d by XPS 5/2 tin oxide peak position of the binding energy is 1.6eV higher than the peak position of the binding energy of metals Sn, the oxygen vacancies than oxygen deficient tin oxide as described above more stable than less (hereinafter, defined as "stable tin oxide."). Therefore, if stable tin oxide is present on the surface of the Sn plating layer, the growth rate of the oxygen-deficient tin oxide is slow. However, in the long term increase in oxygen deficient tin oxide, appearance or inferior strange or coating adhesion yellow. However, a stabilized tin oxide and zirconium oxide may coexist, growth of oxygen deficient tin oxide is suppressed.
[0032]
　To achieve growth inhibiting effect of oxygen deficient tin oxide, 0.2 mg / m on one surface per metal Zr amount 2 or more 50 mg / m 2 or less of zirconium oxide is needed in the coating layer. The content of zirconium oxide is, 0.2 mg / m of a metal Zr content 2 if less than not only the growth inhibiting effect of oxygen deficient tin oxide is insufficient, inferior sulfidation blackening. The content of zirconium oxide is, 50 mg / m of a metal Zr amount 2 when it exceeds, because the zirconium oxide is excessive, degrading the paint adherence. The content of zirconium oxide, a metal Zr content per surface, preferably 1.0 mg / m 2 or more 30 mg / m 2 is less, more preferably in the range of 2.0 mg / m 2 or more 10 mg / m 2 or less it is in the range of.
[0033]
　Tin oxide, Sn3d by XPS 5/2 peak position of the binding energy of is 1.6eV is larger than necessary than the peak position of the binding energy of metals Sn. By the peak position of the binding energy is greater than or equal to 1.6 eV, tin oxide is a stable tin oxide, the growth of oxygen deficient tin oxide is suppressed. On the other hand, Sn3d by XPS 5/2 if the difference is less than 1.6eV and the peak position of the binding energy peak position and Sn metal binding energy of tin oxide is oxygen deficient tin oxide, oxygen-deficient growth of tin oxide to proceed.
[0034]
　Since the higher the tin oxide high bond energy is stabilized, Sn3d tin oxide 5/2 upper limit value of the peak position of the binding energy is not intended to define, in reality, the binding energy of metals Sn is 2.0eV large value of about from peak position.
　That, Sn3d by XPS of the tin oxide 5/2 peak position of binding energy, it is greater at 2.0eV below the range of 1.6eV than the peak position of the binding energy of metals Sn.
　Here, the measurement method described later "Sn3d by XPS of the tin oxide 5/2 peak position of the binding energy is greater peak position 1.6eV higher than the peak position of the binding energy of metals Sn" If is measured, the coating layer, other than the stabilized tin oxide, tin oxide and other structures (e.g., Sn3d by XPS 5/2 less than 1.6eV than the peak position of the binding energy peak position Sn metal binding energy of such as oxygen deficient tin oxide) no problem be included.
[0035]
　The coating layer, a mass ratio per unit area, P amount / metal Zr content is preferably phosphorus to be 0.2 or more and 1 or less is contained further. By containing the P above mass ratio, it becomes zirconium oxide and further has coating layer containing tin oxide dense, easily improving the growth inhibiting effect of the tin oxide. If the amount of P / metal Zr content is less than 0.2, it may become poor growth inhibiting effect of the tin oxide. If the amount of P / metal Zr amount is greater than 1 is, P becomes excessive, the growth inhibitory effects of the tin oxide at the time of the zirconium oxide and tin oxide coexist may become poor. Mass ratio of the amount of P and the metal Zr per unit area (P weight / metal Zr amount) is more preferably 0.3 to 0.8.
[0036]
　Coating layer containing the zirconium oxide and tin oxide may be both mixed state of may be a solid solution of oxides, regardless of its presence state. Further, such as Fe, Ni, Cr, Ca, Na, Mg, Al, Si or the like in the coating layer, there is no problem even contain any elements.
[0037]
　Here, an example of the element concentration profile in the thickness direction of the Sn plated layer and the coating layer of the Sn plated steel sheet of the present disclosure (the depth direction) shown in FIG. Element concentration profile shown in FIG. 1, by analysis in the depth direction of the XPS, a diagram of measuring the distribution of element concentration from the surface of the coating layer to the surface of the steel sheet through the plating layer.
　As shown in FIG. 1, Sn-plated steel sheet of the present disclosure, the surface of the Sn-plated layer containing a metallic Sn, it can be seen that the coating layer and the zirconium oxide and tin oxide coexist exists.
[0038]
　The thickness of the coating layer, SiO by XPS 2 in terms of thickness is preferably 2nm or 100nm or less. When the thickness of the coating layer is less than 2nm, the poor oxygen permeation inhibiting effect for the thickness of the coating layer is too thin, it may oxygen deficient tin oxide tends to grow. On the other hand, when the thickness of the coating layer is 100nm greater is tin oxide itself is likely to cohesive failure for the thickness of the coating layer is too thick, it may be inferior in coating adhesion and corrosion resistance after coating. Not only that, yellowing resistance may sometimes become appearance assume a yellowish from immediately after production of a good thing. The thickness of the coating layer is more preferably 30nm or less the range of 4 nm.
　The thickness of the coating layer, in the XPS depth profiling, Sn which is present as tin oxide, Sn which is present as metallic tin, Zr present as zirconium oxide, the sum of the element concentration is taken as 100%, the surface from a thickness of up area element concentration than 10% of the metal tin (Sn which is present as metallic tin), SiO 2 is a value obtained by conversion thickness.
[0039]
　In coating layer, the content of zirconium oxide (metal Zr amount) and the amount of P is the Sn-plated steel sheet of the present disclosure, e.g., dissolved by immersion in an acidic solution such as hydrofluoric acid and sulfuric acid, the resulting solution the inductively coupled plasma (inductively coupled plasma: ICP) and a value measured by chemical analysis such as emission spectroscopy. Alternatively, the content of zirconium oxide (metal Zr amount) and P amount may be determined by fluorescent X-ray measurement.
[0040]
　In the following, a method for forming a coating layer containing zirconium oxide and tin oxide, is described.
　To form the coating layer, first, to the surface of the Sn-plated layer of the steel sheet that Sn plating layer is formed, to form a zirconium oxide layer containing zirconium oxide.
[0041]
　Zirconium oxide layer containing zirconium oxide, the Sn plated steel sheet is immersed in the immersion bath containing zirconium ion, or by performing a cathodic electrolysis treatment in the cathode electrolyte solution containing zirconium ions, Sn plated layer it can be formed on the surface of the. However, in the immersion process, the zirconium oxide layer surface of the Sn-plated layer is underlying containing zirconium oxide by being etched is formed. Therefore, Sn deposition amount of the plating layer tends to become uneven, Also, since the processing time becomes longer, the industrial production is disadvantageous. On the other hand, at the cathode electrolytic treatment, adhesion-promoting effect by forced charge transfer and surface cleaning and pH increase due to hydrogen generation on the steel sheet surface is also coupled, it is possible to obtain a uniform film. In addition, the cathode electrolytic treatment, by in the cathode electrolyte and nitrate ions and ammonium ions coexist, it is possible short treatment for about several seconds to several tens of seconds. For this reason, the industrial is very advantageous.
　Therefore, the formation of zirconium oxide layer containing zirconium oxide, it is preferable to use a method by cathodic electrolysis treatment.
[0042]
　The concentration of zirconium ions in the catholyte in carrying out the cathodic electrolytic treatment, production facilities may be appropriately adjusted depending on the production rate (capacity). For example, a zirconium ion concentration is preferably 100ppm or 4000ppm or less. Further, the solution containing zirconium ions, fluorine ions, ammonium ions, nitrate ions, no problem also include other components such as sulfate ion.
[0043]
　The source of zirconium ions in the catholyte is, for example, H 2 ZrF 6 can be used zirconium complexes such as. Zr in Zr complexes as described above, Zr by increase in pH at the cathode electrode interface 4+ present in catholyte becomes. Such Zr ions further react with the cathode electrolytic solution, a zirconium oxide. If it contains phosphoric acid in the catholyte, zirconium phosphate is also formed.
[0044]
　Incidentally, the coating layer containing the zirconium oxide and tin oxide, the mass ratio per unit area, in order to contain phosphorus P amount / metal Zr amount is 0.2 to 1.0 (P) the, in the immersion bath or catholyte, it may be contained one-tenth more than 3 times the phosphate ions zirconium ion concentration.
[0045]
　As the solvent for the catholyte when the cathode electrolytic treatment, for example, water can be used such as distillation water. However, the solvent is not intended to be defined in the water, such as distilled water, dissolved substances, depending on the forming method and the like, it can be appropriately selected.
[0046]
　Here, the liquid temperature of the catholyte when the cathode electrolytic treatment is not particularly intended to define, for example, preferably in the range of 10 ° C. or higher 50 ° C. or less. By performing cathodic electrolysis at 50 ° C. or less, formed by very fine particles, it is possible to form a tissue of dense and uniform film layer. On the other hand, if the liquid temperature is lower than 10 ° C., the formation efficiency of the film is poor, requires cooling of the solution when the outside air temperature is high such as in summer, not only economical but also decreases corrosion resistance after coating . The liquid when the temperature exceeds 50 ° C., the zirconium oxide film tissue formed is not uniform, defects, cracks, dense film formed micro cracks generated becomes difficult, starting point of corrosion undesirable because it becomes.
[0047]
　Further, pH of the catholyte is not particularly intended to define, it is preferably 3 to 5. If the pH is less than 3, poor production efficiency of zirconium oxide, if the pH is greater than 5, a large amount occurs precipitated in catholyte, poor continuous productivity.
[0048]
　In order to raising the efficiency of electrolysis to adjust the pH of the catholyte, in the catholyte, such as nitric acid, ammonia water or the like may be added.
[0049]
　Also, the current density at the time of cathodic electrolysis treatment, for example, 0.05 A / dm 2 or more 50A / dm 2 is preferably not more than. Current density is 0.05 A / dm 2 when it is less than can lead to reduction in formation efficiency of zirconium oxide, yellowing resistance and resistance to become formation of the coating layer containing a stable zirconium oxide is difficult well sulfide blackening decreases, also decreases corrosion resistance after coating. Current density is 50A / dm 2 for the case where more than the formation efficiency is too large zirconium oxide, zirconium oxide less coarse and adhesion is formed, which is not preferable. More preferred current density range of, 1A / dm 2 or more 10A / dm 2 or less.
[0050]
　Incidentally, in forming the zirconium oxide layer, the time of the cathode electrolytic treatment, not to question. The content of zirconium oxide film layer which aimed to (metallic Zr amount) may be adjusted time appropriate cathodic electrolytic treatment in accordance with the current density.
[0051]
　As the energization pattern when the cathode electrolytic treatment, there is no problem even it is intermittently energized a continuous energization.
[0052]
　Coating layer containing zirconium oxide and tin oxide, a zirconium oxide layer containing zirconium oxide, obtained by anodic electrolysis at an anode electrolyte. Not particularly defined for specific components of the anolyte when anodic electrolysis treatment. However, the liquid property of anolyte, it is preferred that the alkaline weakly acidic. The alkaline weakly acidic here, pH is meant 3 to 14. If pH is within this range, the solubility of the Sn-plated layer at the anode electrolytic solution becomes gentle, it is possible to stably form a coating layer containing a stable tin oxide.
[0053]
　As examples of the anode electrolyte when anodic electrolysis treatment, hydroxides of alkali metals and alkaline earth metals, alkali metals and alkaline earth metal salts (carbonates, phosphates, organic acid salts, borates , and an aqueous solution containing an electrolyte such as sulfuric acid salts, etc.). Specifically, for example, as the anolyte, sodium carbonate, sodium bicarbonate, sodium diphosphate, trisodium citrate, ammonium one tartrate, aqueous solutions containing an electrolyte such as sodium sulfate.
　The lower limit of the concentration of the electrolyte is not particularly defined, it is preferable that the concentration satisfying the above-0.1 S / m as the electrical conductivity. But not limit the concentration of these electrolytes also specifically defined, when the concentration of the electrolyte is too large precipitates during storage, because it can cause problems such as pipe clogging, and less solubility in 0 ℃ each electrolyte it is preferable. The concentration of the electrolyte is preferably in electric conductivity as the concentration satisfying the following 0.5S / m or more 4S / m, more preferably, at a concentration satisfying the following 1S / m than 2.5S / m electrical conductivity is there.
　The electric conductivity may be measured using a commercially available electric conductivity meter, for example, it is possible to use a conductivity cell CT-27112B, such as manufactured by DKK-TOA Corporation.
[0054]
　As a solvent for the anolyte when anodic electrolysis treatment, for example, water can be used such as distillation water. However, the solvent is not intended to be restricted to water such as distilled water.
[0055]
　Here, the liquid temperature of the anolyte when anodic electrolysis treatment is not particularly intended to define, preferably in the range of less than 60 ° C. 5 ° C. or higher, more preferably in the range of 15 ℃ above 50 ° C. or less is there. If the liquid temperature is too low, poor efficiency of electrolysis, stable tin oxide is less likely to generate. On the other hand, if the liquid temperature is too high, the evaporation of the solvent the anolyte is inferior in prominent workability and operation stability, is difficult to obtain a uniform stable tin oxide.
[0056]
　The current density at the time of anodic electrolysis treatment is not particularly intended to define, for example, 0.5A / dm 2 or more 10A / dm 2 preferably has the following range. Current density 0.5A / dm 2 or more 10A / dm 2 when it is below, the stable tin oxide can be formed uniformly and stably. Current density 0.5A / dm 2 when it is less than, it is necessary to increase the electrolytic treatment time, decrease in corrosion resistance after painting associated with the dissolution of the Sn-plated layer is cheaper occur. On the other hand, the current density is 10A / dm 2 when exceeding significantly the hydrogen generation in the Sn plating layer is not preferred on productivity for the dissolution of Sn plating layer due to pH increase occurs, the uneven tin oxide formation yellowing and sulfidation blackening tends to decrease. Preferred current density range, 1.0A / dm 2 or more 3A / dm 2 or less.
[0057]
　The time of anodic electrolysis treatment is not particularly defined. Current density, electrode length, depending on the production rate (sheet passing speed), etc., can be arbitrarily determined.
[0058]
　The above-described cathode electrolytic treatment and the thickness of the coating layer formed through an anodic electrolytic treatment, mainly energization amount when anodic electrolysis can be controlled by (quantity of electricity), the thickness of the as the amount of current is large coating layer It becomes thicker. Recommended, in order to obtain a coating layer of 100nm or less in thickness than 2nm is the amount of current during anodic electrolysis 0.5 C / dm 2 or more 30C / dm 2 is preferably not more than. To obtain a 30nm or less of the coating layer or 4nm is the amount of current during anodic electrolysis 1C / dm 2 or more 15C / dm 2 is preferably not more than.
[0059]
　As the energization pattern when anodic electrolysis treatment, there is no problem even it is intermittently energized a continuous energization.
Example
[0060]
　Subsequently, while showing Examples and Comparative Examples, a method for manufacturing the Sn-plated steel sheet and the Sn-plated steel sheet of the present disclosure will be specifically described. Incidentally, the embodiment described below, merely only one example of a manufacturing method of the Sn plated steel sheet and the Sn-plated steel sheet of the present disclosure, the production method of the Sn-plated steel sheet and the Sn-plated steel sheet of the present disclosure be limited to the following examples not.
[0061]

　Preparation method of test material will be described. The test materials of the examples below were produced according to the manufacturing method of the test material.
　First, with respect to low-carbon cold-rolled steel sheet having a thickness of 0.2 mm, as a pretreatment, electrolytic alkali degreasing, washing with water, dilute sulfuric acid immersion pickling, washed with water, subjected to electrical Sn plating using phenolsulfonic acid bath, further then the heat melting treatment. To form a Sn plating layer on both surfaces of the steel sheet through these processes. Adhesion amount of Sn plating layer is about 2.8 g / m per one side 2 was the standard. Adhesion amount of Sn plated layer was adjusted by changing the energizing time.
[0062]
　Then, the steel sheet to form a Sn plating layer, and a cathode electrolytic treatment in an aqueous solution containing zirconium fluoride (catholyte), to form a zirconium oxide layer on the surface of the Sn plated layer. The liquid temperature of the catholyte was set to 35 ° C., and, pH of the catholyte was adjusted to be 3 to 5, the current density and the cathodic electrolysis treatment time of the cathode electrolytic treatment, the coating layer of the aimed and adjusted appropriately according to the content of zirconium oxide (metal Zr content).
[0063]
　Further, the steel sheet to form a Sn plating layer and a zirconium oxide layer, and an anode electrolysis in electric conductivity 2.0S / m of sodium hydrogen carbonate solution (anolyte), zirconium oxide layer, zirconium oxide was coating layer containing tin oxide and. The liquid temperature of the anolyte is a 25 ° C., and the current density of the anodic electrolysis treatment is 2A / dm 2 was set to. Note that in some level, changing the type and anodic electrolysis treatment conditions of anolyte. Anodic electrolysis treatment time were suitably adjusted. Incidentally, pH of the anolyte was determined with a glass electrode.
[0064]
　For Sn-plated steel sheet produced in this manner was a variety of evaluation described below.
[0065]
[Adhesion amount per one side of the Sn-plated layer (metal Sn of Sn plating layer)
　deposition amount per surface of the Sn-plated layer (metal Sn of Sn plating layer) is measured by the "ICP emission spectrometry described above It was measured by the method ".
[0066]
[The content of zirconium oxide coating layer (metal Zr amount) and the P content]
　The content of zirconium oxide coating layer (metal Zr amount) and the P content is as follows.
　The content of metal Zr content and P content were prepared test pieces of a plurality of coating layers with steel is known. Then, each test piece, by a fluorescent X-ray analyzer (manufactured by Rigaku Corporation ZSX Primus), from the surface of the coating layer of the specimen to measure the intensity of the fluorescent X-ray derived from the metal Zr and P in advance. Then, a calibration curve showing the relationship between the intensity and the metal Zr and P of the measured X-ray fluorescence, were prepared, respectively.
　On top of that, to prepare a test piece of the Sn-plated steel sheet to be measured. The surface of the coating layer of the specimen X-ray fluorescence analyzer (Rigaku ZSX Primus), measuring the intensity of the fluorescent X-ray derived from the metal Zr and P. Obtained by utilizing the calibration curve for the previously prepared metal Zr and P and X-ray fluorescence intensity was calculated the content of zirconium oxide coating layer (metal Zr amount) and the P content.
　Incidentally, measurement conditions, X-rays source Rh, tube voltage 50 kV, tube current 60 mA, the analyzing crystal LiF1, was measured diameter 30 mm.
[0067]
[Sn3d tin oxide in the coating layer in the XPS 5/2 peak position of the binding energy]
　to the surface of the coating layer, to perform measurements by XPS (ULVAC-PHI manufactured PHI Quantera SXM), the coating layer Sn3d tin oxide 5/2 was examined peak position of the binding energy (in the table referred to as "XPS energy peak position").
　Incidentally, measurement conditions, X-rays source mono-AlK ray (hν = 1466.6eV, 100.8W), X diameter 100Myuemufai, detection depth of several nm (takeoff angle 45 °), was analyzed range 1400 × 100 [mu] m.
　Then, Sn3d tin oxide 5/2 if 1.6eV higher than the large peak position of binding energy peak position Sn metal binding energy of (= 484.9eV), as stable tin oxide is mainly formed It was evaluated as "OK". If it is less than 1.6 eV, oxygen deficient tin oxide was evaluated as "NG" as being predominantly formed. Evaluate the "OK" was passed.
[0068]
[Coating layer thickness]
　The thickness of the coating layer was measured by XPS (ULVAC-PHI manufactured PHI Quantera SXM). Specifically, to prepare a test piece of the Sn-plated steel sheet to be measured. From the surface of the coating layer of the test piece, and performing analyzes XPS (ULVAC-PHI manufactured PHI Quantera SXM) due to the thickness direction (depth direction), Sn which is present as tin oxide, Sn which is present as metallic tin, zirconium oxide there Zr, the sum of the element concentration is 100 percent things, from the surface, the thickness of up element concentration following 10% region of the metal tin (Sn which is present as metallic tin) SiO 2 in terms of thickness calculated.
　Incidentally, measurement conditions, X-rays source mono-AlK ray (hν = 1466.6eV, 100.8W), X diameter 100Myuemufai, detection depth of several nm (takeoff angle 45 °), analytical range 1400 × 100 [mu] m, neutralized gun 1.0 V, 20 .mu.A, sputtering conditions Ar + , the acceleration voltage 1 kV, sputter rate 1.5 nm / min (SiO 2 was converted value).
[0069]
[Yellowing resistance]
　The test material of the Sn-plated steel sheet, 40 ° C., subjected to humidity test for placing 4 weeks in 80% RH constant temperature and humidity was maintained at tank, the amount of change in color difference b * value before and after the humidity test △ b * the asking, was evaluated. If △ b * is 1 or less is "A", if 1 exceed 2 hereinafter as "B", if 2 exceed 3 below as "C", and "NG" if exceeded 3 . Evaluation "A", was passed the "B" and "C". b * was measured using a Suga Tester manufactured by SC-GV5 a commercial colorimeter. b * measurement conditions, the light source C, total reflection, a measurement diameter 30 mm.
[0070]
[Coating adhesion]
　coating adhesion was evaluated as follows.
　The test material of the Sn-plated steel sheet, after humidity test by the method described in [yellowing resistance, surface, the epoxy resin paint commercial cans 7 g / m on a dry weight 2 was applied, 10 minutes baking at 200 ° C. , it was placed in a room temperature for 24 hours. Thereafter, the obtained Sn-plated steel sheet, placed flaws reaching the steel sheet surface in a grid pattern (scratches at 3mm apart by vertically and horizontally seven), it was evaluated by the tape peeling test at that site. If not, release coating of tape applying sites are all set to "A", as long recognized coating peeling wound portion around the crosscut and "B", the coating film peeling is observed in the cross-cut of the square if the "NG". Evaluation "A", and the "B" was passed.
[0071]
[Sulfidation blackening]
　sulfidation blackening was evaluated as follows.
　Above the surface of the coating adhesion in Test material of the Sn-plated steel sheet was produced and humidity test by the method described in, 7 g / m on a dry weight of an epoxy resin paint commercial cans 2 after application, 10 at 200 ° C. min baking, placed in room temperature for 24 hours. Thereafter, the resulting Sn-plated steel sheet is cut into a predetermined size, sodium dihydrogen phosphate 0.3%, sodium hydrogen phosphate 0.7%, an aqueous solution comprising the L- cysteine hydrochloride from 0.6% immersed in, it performs retorting 121 ° C. · 60 minutes in a sealed container was evaluated from the appearance after the test. If the change in appearance was observed at all before and after the test was "A", slightly (10% less) as long recognized blackened as "B", as long recognized blackening 10% excess area of the test surface and "NG". Evaluation "A", was passed the "B".
[0072]
[Corrosion resistance after painting]
　after painting corrosion resistance was evaluated in the following manner.
　Above the surface of the coating adhesion in Test material of the Sn-plated steel sheet was produced and humidity test by the method described in, 7 g / m on a dry weight of an epoxy resin paint commercial cans 2 after application, 10 at 200 ° C. min baking, placed in room temperature for 24 hours. Thereafter, the resulting Sn-plated steel sheet was cut into a predetermined size, the occurrence or non-occurrence of rust after immersion for 7 days at 60 ° C. in a commercially available tomato juice, was visually evaluated. If rust is observed at all the "A", as long recognized rust 10% or less of the area of the entire test surface and "B", as long recognized rust area ratio of more than 10% of the total test surface " It was NG ". Evaluation "A" and "B" was passed.
[0073]

　Table 1 shows the result in the case of changing the content of the zirconium oxide coating weight and coating layer of the Sn-plated layer. Zirconium concentration in the solution containing zirconium fluoride was set to 1400 ppm. After forming the zirconium oxide layer, relative to the zirconium oxide layer, the electrical conductivity of 2.0S / m of sodium hydrogen carbonate solution (liquid: weakly acidic to alkaline, pH = 8) and anodic electrolytic treatment in to form a coating layer. The liquid temperature of the anolyte is a 25 ° C., energization amount of the anodic electrolytic treatment 2C / dm 2 was set to.
　Moreover, A13 is an example, to prepare a test material without performing heating and melting treatment after Sn plating.
[0074]
　As a comparison, it was prepared together with the following test materials.
　Are Comparative Examples a1 ~ a2: after forming the Sn plating layer on both surfaces of the steel sheet to form a zirconium oxide layer, the test material is not an anodic electrolysis in a zirconium oxide layer
　as a comparative example a7: Sn on both surfaces of the steel sheet after forming the plating layer, prior to forming the zirconium oxide layer, in the electric conductivity of 2.0S / m, the liquid temperature 25 ° C. in sodium bicarbonate solution (anolyte), density of 2A current / dm 2 under the conditions of the anodic electrolysis treatment was performed, then, to form a zirconium oxide layer, the test material is not an anodic electrolysis in a zirconium oxide layer
　is a comparative example a8: after forming the Sn plating layer on both surfaces of the steel sheet, liquid temperature 35 ° C. , in an aqueous solution containing pH4 of zirconium fluoride, a current density of 3A / dm 2 under the conditions of, to form a zirconium oxide layer in an alternating electrolysis treatment performed alternately a cathode electrolytic treatment and anodic electrolysis treatment, di Koniumu oxide layer on the test material is not an anodic electrolysis treatment
　is a comparative example a9: after forming the Sn plating layer on both surfaces of the steel sheet, the Sn-plated layer of the steel sheet, the electric conductivity of 2.0S / m, the liquid temperature 25 ℃ among sodium bicarbonate solution (anolyte), a current density of 2A / dm 2 was carried anodic electrolysis treatment, then the test material does not form a zirconium oxide layer
　in Table 1 is a comparative example a1 ~ a2 , properties of the zirconium oxide layer in a7, a8 (eg not subjected to anodic electrolysis in a zirconium oxide layer) is described in the column of "film layer".
　Further, properties of the tin oxide layer in a9 is a comparative example will be listed in the "coating layer".
[0075]
[Table 1]

[0076]
　As is apparent from Table 1, the range of the present disclosure A1 ~ A13 are all performance is good. On the other hand, a1 ~ a9 is a comparative example, yellowing resistance, coating adhesion, sulfidation blackening, we are understood that any of the corrosion resistance after coating is deteriorated.
　In particular, as in Comparative examples a7, after the formation of the Sn-plated layer on both surfaces of the steel sheet, before the formation of the zirconium oxide layer, be performed an anodic electrolysis treatment, the zirconium oxide layer is then formed , it can be seen that stable tin oxide is not primarily formed.
　As comparative examples a8, be formed zirconium oxide layer in an alternating electrolysis treatment performed alternately a cathode electrolytic treatment and anodic electrolysis treatment, the zirconium oxide layer stabilized tin oxide is formed primarily it can be seen that does not.
　As in the comparative examples a9, without forming a zirconium oxide layer, when carrying out the anodic electrolytic treatment in Sn-plated layer of the steel sheet, the tin oxide layer is formed as a film layer. However, the tin oxide layer, it can be seen that not a stable tin oxide layer.
[0077]

　Table 2 shows the result in the case of changing the thickness of the coating layer. The thickness of the coating layer was changed by changing the energization amount of the anodic electrolysis.
[0078]
[Table 2]

[0079]
　As is apparent from Table 2, the thicker the thickness of the coating layer, is a measure of yellowing △ b * is tends to decrease, if the thickness of the coating layer is 4nm or more, △ b * is particularly small it can be seen.
[0080]

　Table 3 shows the results of a case that contains phosphorus in the film layer. These test material is a cathode electrolyte solution containing zirconium ions 1400ppm obtained by addition of phosphate ion 60 ppm ~ 5000 ppm, and the steel sheet Sn plating layer was formed was produced by cathodic electrolysis treatment.
[0081]
[table 3]

[0082]
　As is apparent from Table 3, that the phosphorus contained in the coating layer, is a measure of yellowing △ b * is tends to decrease, P amount / metal Zr amount is 0.2 or more 1 less is test material is found to be particularly △ b * is small.
[0083]

　Table 4 to Table 7 shows the result when the conditions for forming the zirconium oxide layer (cathode electrolytic treatment conditions) with the formation of the coating layer conditions and (anodic electrolysis treatment condition) were variously changed.
　As a comparison, it was prepared together with the following test materials.
　Are Comparative Examples d1 ~ d2: after forming the Sn plating layer on both surfaces of the steel sheet to form a zirconium oxide layer, the test material is not an anodic electrolysis in a zirconium oxide layer
　In Table 1 is a comparative example d1 characteristics of the zirconium oxide layer in ~ d2 (example not subjected to anodic electrolysis in a zirconium oxide layer) is described in the column of "film layer".
[0084]
[Table 4]

[0085]
[table 5]

[0086]
[Table 6]

[0087]
[Table 7]

[0088]
　As is apparent from Table 4 to Table 7, the performance of the test material produced with reference to the conditions specified in this disclosure, it can be seen that both are good.
[0089]
　Having described in detail the present disclosure, the present disclosure is not limited to such an example. It would be appreciated by those ordinarily skilled in the art that belongs present disclosure, 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 disclosure.
Industrial Applicability
[0090]
　Thus, Sn-plated steel sheet of the present disclosure, without the need for conventional chromate treatment, yellowing resistance, paint adhesion, and it is excellent in sulfidation resistance blackening, as a can material is environmentally friendly, food cans, can be widely used, such as in beverage cans, use value of the industry is extremely high.
[0091]
　Japanese disclosure of patent application 2016-103382 its entirety is incorporated herein by reference.
　All documents described herein, patent applications, and technical standards, each individual publication, patent application, and that the technical specification is incorporated by reference to the same extent as if marked specifically and individually, It incorporated by reference herein.

claims
[Requested item 1]
　And the steel sheet,
　is formed on at least one surface of said steel sheet contains, by mass%, the metal Sn 0.1 g / m 2 or more 15 g / m 2 and the Sn plating layer containing less,
　is formed on a surface of the Sn plating layer, a zirconium oxide and the film layer containing a thing as tin oxide,
　has a
　content of the zirconium oxide in the coating layer is, 0.2 mg / m of a metal Zr weight 2 50 mg / m or more 2 or less,
　said Sn3d by X-ray photoelectron spectroscopy of the tin oxide in the coating layer 5/2 peak position of the binding energy is greater than 1.6eV than the peak position of the binding energy of metals Sn, Sn-plated steel sheet.
[Requested item 2]
　The thickness of the coating layer is at 2nm or 100nm or less, Sn-plated steel sheet according to claim 1.
[Requested item 3]
　The coating layer has a weight ratio per unit area, further contains phosphorus P amount / metal Zr amount is 0.2 or more and 1 or less, Sn-plated steel sheet according to claim 1 or 2.