Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
  • C23C28/345—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates with at least one oxide layer
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
  • C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
  • C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
  • C23C22/34—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides
  • C23C22/36—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides containing also phosphates
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
  • C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
  • C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
  • C23C22/34—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides
  • C23C22/36—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides containing also phosphates
  • C23C22/361—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides containing also phosphates containing titanium, zirconium or hafnium compounds
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
  • C23C28/321—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer with at least one metal alloy layer
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
  • C23C28/322—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer only coatings of metal elements only
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D3/00—Electroplating: Baths therefor
  • C25D3/02—Electroplating: Baths therefor from solutions
  • C25D3/30—Electroplating: Baths therefor from solutions of tin
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D3/00—Electroplating: Baths therefor
  • C25D3/02—Electroplating: Baths therefor from solutions
  • C25D3/56—Electroplating: Baths therefor from solutions of alloys
  • C25D3/60—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of tin
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
  • C25D5/48—After-treatment of electroplated surfaces
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
  • C25D5/48—After-treatment of electroplated surfaces
  • C25D5/50—After-treatment of electroplated surfaces by heat-treatment
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D7/00—Electroplating characterised by the article coated
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D7/00—Electroplating characterised by the article coated
  • C25D7/06—Wires; Strips; Foils
  • C25D7/0614—Strips or foils
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D9/00—Electrolytic coating other than with metals
  • C25D9/04—Electrolytic coating other than with metals with inorganic materials
  • C25D9/08—Electrolytic coating other than with metals with inorganic materials by cathodic processes

Definitions

• the present disclosure relates to surface-treated steel sheets, and in particular to surface-treated steel sheets with excellent adhesion to BPA (bisphenol A)-free paint.
• the surface-treated steel sheets of the present disclosure can be suitably used in containers such as cans.
• the present disclosure also relates to a method of producing the surface-treated steel sheet.
• a Sn plating steel sheet (tinplate), one type of surface-treated steel sheet, is widely used as material for various metal cans such as beverage cans, food cans, pails, and 18-liter cans because of its excellent corrosion resistance, weldability, workability, and ease of production.
• BPA-free paint using polyester-based resins that do not contain BPA are being developed (PTL 6, 7), and demand exists for replacing epoxy-based paint.
• tinplate which has been used as steel sheets for cans, has poor adhesion to BPA-free paint compared to adhesion to epoxy-based paint. Therefore, the application of BPA-free paint to various metal cans has not progressed due to insufficient corrosion resistance to various contents.
• a surface treatment layer can be formed without using hexavalent chromium. Also according to PTL 8, the above method can obtain a surface-treated steel sheet with excellent adhesion to epoxy-based paint.
• the surface-treated steel sheet obtained by the conventional method as proposed in PTL 8 has poor adhesion to BPA-free paint, resulting in insufficient BPA-free paint corrosion resistance. Replacement with BPA-free paint while ensuring corrosion resistance to various contents has therefore not been possible.
• a surface-treated steel sheet that uses no hexavalent chromium and that has excellent adhesion to BPA-free paint can be provided.
• the surface-treated steel sheet of the present disclosure can be suitably used as a material for containers and the like.
• a surface-treated steel sheet in an embodiment of the present disclosure includes, on at least one side of the steel sheet, a Sn plating layer and a coating layer disposed on the Sn plating layer, the coating layer containing at least one of Zr oxide and Ti oxide.
• any steel sheet can be used as the above steel sheet without any particular limitation, but a steel sheet for cans is preferred.
• a steel sheet for cans is preferred.
• an ultra low carbon steel sheet or low carbon steel sheet can be used as the steel sheet.
• the method of producing the steel sheet is not limited, and a steel sheet produced by any method may be used, but it typically suffices to use a cold-rolled steel sheet.
• the cold-rolled steel sheet can be produced by general production processes, for example, hot rolling, pickling, cold rolling, annealing, and temper rolling.
• the chemical composition of the steel sheet is not limited, but the steel sheet may contain C, Mn, Cr, P, S, Si, Cu, Ni, Mo, Al, and unavoidable impurities to the extent that the effects of the scope of the present disclosure are not impaired.
• a steel sheet with the chemical composition specified in ASTM A623M-09, for example, can be suitably used as the steel sheet.
• the Sn plating layer need only be provided on at least one side of the steel sheet but may be provided on both sides.
• the Sn plating layer need only cover at least a portion of the steel sheet but may cover the entire side on which the Sn plating layer is provided.
• the Sn plating layer may be a continuous layer or a discontinuous layer.
• the discontinuous layer is, for example, a layer with an island-like structure.
• the Sn plating layer includes the case of a portion of the Sn plating layer being alloyed.
• the Sn plating layer includes the case in which a portion of the Sn plating layer is a Sn alloy layer due to hot melt treatment after Sn plating.
• the Sn alloy layer include an Fe-Sn alloy layer and an Fe-Sn-Ni alloy layer.
• a portion of the steel sheet side of the Sn plating layer can be made into an Fe-Sn alloy layer.
• a portion of the steel sheet side of the Sn plating layer can be made into either or both of an Fe-Sn-Ni alloy layer and an Fe-Sn alloy layer.
• the Sn coating weight in the Sn plating layer is not limited and can be any amount. However, from the perspective of further improving the appearance and corrosion resistance of the surface-treated steel sheet, the Sn coating weight is preferably set to 20.0 g/m 2 or less per side of the steel sheet. From the same perspective, the Sn coating weight is preferably set to 0.1 g/m 2 or more and more preferably to 0.2 g/m 2 or more. From the perspective of further improving workability, the Sn coating weight is even more preferably set to 1.0 g/m 2 or more.
• the Sn coating weight can be measured by the electrolytic stripping method specified in JIS G 3303.
• the Sn plating layer can be formed by any method without limitation, including methods such as electroplating and hot dip coating.
• any plating bath can be used. Examples of plating baths that can be used include a phenolsulfonic acid Sn plating bath, a methanesulfonic acid Sn plating bath, and a halogen-based Sn plating bath.
• reflow treatment may be performed.
• the Sn plating layer is heated to a temperature at or above the melting point of Sn (231.9 °C) to form an alloy layer such as an Fe-Sn alloy layer on the bottom layer (steel sheet side) of the unalloyed Sn plating layer. If the reflow treatment is omitted, a Sn plating steel sheet with an unalloyed Sn plating layer is obtained.
• the surface side of the Sn plating layer may contain Sn oxide or may contain no Sn oxide at all.
• the surface side of the Sn plating layer preferably does contain Sn oxide.
• Sn oxide can be formed by reflow treatment or by dissolved oxygen contained in water used in water washing after Sn plating, the amount of Sn oxide contained in the Sn plating layer is preferably controlled by the below-described pretreatment or the like.
• the surface-treated steel sheet can further optionally include a Ni-containing layer.
• the surface-treated steel sheet according to an embodiment of the present disclosure can further include a Ni-containing layer disposed below the Sn plating layer.
• a surface-treated steel sheet in an embodiment of the present disclosure includes, on at least one side of the steel sheet, a Ni-containing layer, a Sn plating layer disposed on the Ni-containing layer, and a coating layer disposed on the Sn plating layer and containing at least one of Zr oxide and Ti oxide.
• any layer that contains nickel can be used.
• a Ni layer and a Ni alloy layer can be used.
• the Ni layer is, for example, a Ni plating layer.
• the Ni alloy layer is, for example, a Ni-Fe alloy layer.
• the method of forming the Ni-containing layer is not limited, and any method, such as electroplating, can be used.
• the Ni-Fe alloy layer can be formed by forming a Ni layer on the steel sheet surface, by electroplating or another such method, and then annealing.
• the Ni coating weight of the Ni-containing layer is preferably set to 2 mg/m 2 or more per side of the steel sheet. From a cost perspective, the Ni coating weight per side of the steel sheet is preferably set to 2000 mg/m 2 or less.
• the Ni coating weight of the Ni-containing layer is measured by a calibration curve method using X-ray fluorescence.
• a plurality of steel sheets with known Ni coating weight are prepared, the X-ray fluorescence intensity derived from Ni is measured for the plates in advance, and the relationship between the measured X-ray fluorescence intensity and the Ni coating weight is linearly approximated to yield a calibration curve.
• the X-ray fluorescence intensity derived from Ni in the surface-treated steel sheet can then be measured, and the above-described calibration curve can be used to determine the Ni coating weight of the Ni-containing layer.
• a coating layer containing at least one of Zr oxide and Ti oxide exists on the Sn plating layer.
• the inclusion of at least one of Zr oxide and Ti oxide in the coating layer is necessary to obtain excellent adhesion to BPA-free paint.
• the total coating weight of the Zr oxide and Ti oxide is preferably 0.3 mg/m 2 or more, more preferably 0.4 mg/m 2 or more, and even more preferably 0.5 mg/m 2 or more, per side of the steel sheet in terms of the amount of metal Zr and amount of metal Ti.
• No upper limit is placed on the total coating weight of Zr oxide and Ti oxide in the coating layer either. However, if the total coating weight of Zr oxide and Ti oxide is excessively high, the adhesion to the BPA-free paint may be compromised due to cohesion failure of the coating layer.
• the total coating weight of the Zr oxide and Ti oxide is preferably 50.0 mg/m 2 or less, more preferably 45.0 mg/m 2 or less, and even more preferably 40.0 mg/m 2 or less, per side of the steel sheet in terms of the amount of metal Zr and amount of metal Ti.
• the value yielded by conversion to the amount of metal Zr is used as the coating weight of Zr oxide
• the value yielded by conversion to the amount of metal Ti is used as the coating weight of Ti oxide.
• the coating weight of Zr oxide in the coating layer is measured by a calibration curve method using X-ray fluorescence.
• a plurality of steel sheets with known Zr coating weight are prepared, the X-ray fluorescence intensity derived from Zr is measured for the plates in advance, and the relationship between the measured X-ray fluorescence intensity and the coating weight as metal Zr is linearly approximated to yield a calibration curve.
• the X-ray fluorescence intensity derived from Zr in the surface-treated steel sheet can then be measured, and the above-described calibration curve can be used to determine the coating weight of Zr oxide in the coating layer in terms of metal Zr.
• the coating weight of Ti oxide in the coating layer is also measured by a calibration curve method using X-ray fluorescence.
• a calibration curve method using X-ray fluorescence First, a plurality of steel sheets with known Ti coating weight are prepared, the X-ray fluorescence intensity derived from Ti is measured for the plates in advance, and the relationship between the measured X-ray fluorescence intensity and the coating weight as metal Ti is linearly approximated to yield a calibration curve.
• the X-ray fluorescence intensity derived from Ti in the surface-treated steel sheet can then be measured, and the above-described calibration curve can be used to determine the coating weight of Ti oxide in the coating layer in terms of metal Ti.
• the coating layer may contain P from the perspective of further improving adhesion to BPA-free paint.
• the coating weight of P is preferably 50.0 mg/m 2 or less per side of the steel sheet, since adhesion to BPA-free paint may be impaired due to cohesion failure of the coating layer.
• No lower limit is placed on the coating weight of P in the coating layer, and the coating weight of P may, for example, be 0.0 mg/m 2 , i.e., no P whatsoever may be contained.
• the coating weight of P in the coating layer is measured by a calibration curve method using X-ray fluorescence.
• a plurality of steel sheets with known P coating weight are prepared, the X-ray fluorescence intensity derived from P is measured for the plates in advance, and the relationship between the measured X-ray fluorescence intensity and the P coating weight is linearly approximated to yield a calibration curve.
• the X-ray fluorescence intensity derived from P in the surface-treated steel sheet can then be measured, and the above-described calibration curve can be used to determine the coating weight of P in the coating layer.
• the coating layer may contain Mn from the perspective of further improving adhesion to BPA-free paint.
• the coating weight of Mn is preferably 50.0 mg/m 2 or less per side of the steel sheet, since adhesion to BPA-free paint may be impaired due to cohesion failure of the coating layer.
• No lower limit is placed on the coating weight of Mn in the coating layer, and the coating weight of Mn may, for example, be 0.0 mg/m 2 , i.e., no Mn whatsoever may be contained.
• the aforementioned coating layer may contain Sn. No upper limit is placed on the Sn content in the coating layer.
• the coating layer need not contain Sn, i.e., the content may be 0.0 mg/m 2 .
• the aforementioned coating layer may contain C. No upper limit is placed on the C content in the coating layer.
• the coating layer need not contain C, i.e., the content may be 0.0 mg/m 2 .
• the aforementioned coating layer may contain elements other than Zr, Ti, O, Sn, Mn, P, Ni, and C, along with the below-described K, Na, Mg, and Ca.
• Elements other than those described above include metallic impurities such as Cu, Zn, and Fe, and elements such as S, N, F, Cl, Br, and Si, contained in the aqueous solution used in the coating formation process described below.
• an excessive presence of elements other than Zr, Ti, O, Sn, Mn, P, Ni, C, K, Na, Mg, and Ca may reduce adhesion to BPA-free paint.
• the contact angle of ethylene glycol on the surface-treated steel sheet be 50° or less.
• the contact angle of ethylene glycol is preferably set to 48° or less, and even more preferably to 45° or less. No lower limit is placed on the contact angle of ethylene glycol, and the contact angle may be 0°, because a lower contact angle is preferable from the perspective of improving adhesion to BPA-free paint.
• the contact angle of ethylene glycol may be 5° or more, or 8° or more.
• the surface of the surface-treated steel sheet in the present disclosure i.e., the surface of the coating layer containing at least one of Zr oxide and Ti oxide
• the contact angle of ethylene glycol does not change significantly after heat treatment equivalent to paint baking. It is assumed that such thermal stability of the surface state also contributes to improved adhesion to BPA-free paint. Therefore, the contact angle of ethylene glycol on the surface-treated steel sheet after heat treatment equivalent to painting is also preferably 50° or less, more preferably 48° or less, and even more preferably 45° or less.
• No lower limit is placed on the contact angle of ethylene glycol on the surface-treated steel sheet after heat treatment equivalent to painting, and the contact angle may be 0°, but the contact angle may be 5° or more, or 8° or more.
• the conditions of the heat treatment equivalent to painting are set to a maximum temperature of 200 °C and a holding time at the maximum temperature of 10 minutes.
• the contact angle of ethylene glycol can be measured by the ⁇ /2 method.
• the temperature of the surface-treated steel sheet to be measured is set to 20 °C, and ethylene glycol at a temperature of 20 °C is dropped onto the surface of the surface-treated steel sheet.
• the contact angle after 1 second from dropping is calculated by the 0/2 method. More specifically, measurement can be made by the method described in the Examples.
• the surface of the surface-treated steel sheet may be coated with an anti-rust oil such as CSO (Cottonseed Oil), DOS (Dioctyl Sebacate), and ATBC (Acetyl Tributyl Citrate).
• the contact angle measured by the method described in the Examples after vaporizing the coated oil by the heat treatment equivalent to painting is taken as the contact angle of ethylene glycol of the surface-treated steel sheet after painting with oil.
• the surface-treated steel sheet of the present disclosure is stable with respect to heat treatment. Therefore, if the contact angle measured after the aforementioned heat treatment and the atomic ratio of the adsorbed elements described below satisfy the conditions of the present disclosure, the surface-treated steel sheet before the aforementioned heat treatment is also considered to achieve the effects of the present disclosure.
• additives such as rust inhibitors contained in the painted oil may remain on the surface of the surface-treated steel sheet after heat treatment equivalent to painting, the amount thereof is so small that it does not affect the above-described contact angle of ethylene glycol and atomic ratio of adsorbed elements.
• the present disclosure focuses on ethylene glycol instead of water, and we discovered that by adjusting the surface to have a high affinity for ethylene glycol, firm adhesion to BPA-free paint can be ensured. It can thus be said that the present disclosure is based on a technical concept that is completely different from the conventional technology described above.
• the mechanism for improving adhesion to BPA-free paint by adjusting the surface to have a high affinity for ethylene glycol is not clear.
• ethylene glycol is one of the hydroxyl monomers that is a component of the polyester resin that constitutes BPA-free paint, it is assumed that adjusting the surface to have a high affinity for ethylene glycol improves the adhesion to BPA-free paint.
• the contact angle of ethylene glycol on the surface-treated steel sheet of the present disclosure is 50° or less, and the surface is chemically active. Therefore, cations of elements such as K, Na, Mg, and Ca are easily adsorbed on the surface of the surface-treated steel sheet.
• simply setting the contact angle of ethylene glycol to 50° or less does not achieve the intended adhesion, due to the effect of the adsorbed cations.
• the adhesion to BPA-free paint can be improved in the present disclosure by reducing the amount of the cations adsorbed on the surface of the surface-treated steel sheet.
• the total atomic ratio of K, Na, Mg, and Ca adsorbed on the surface of the surface-treated steel sheet to all elements is 5.0 % or less, preferably 3.0 % or less, and more preferably 1.0 % or less.
• the total atomic ratio can be measured by XPS. In the measurement, it suffices to determine the atomic ratios of K, Na, Mg, and Ca to all elements from the integrated intensity of the narrow spectra of K2p, Na1s, Ca2p, and Mg1s at the top surface of the surface-treated steel sheet, using the relative sensitivity factor method.
• measurement can be made by the method described in the Examples.
• the atomic ratio measured by the method described in the Examples after vaporizing the painted oil by the heat treatment equivalent to painting is taken as the atomic ratio of the elements adsorbed to the surface-treated steel sheet after painting with oil.
• a surface-treated steel sheet with the aforementioned characteristics can be produced by the method described below.
• a method of producing a surface-treated steel sheet in an embodiment of the present disclosure is a method of producing a surface-treated steel sheet that includes, on at least one side of the steel sheet, a Sn plating layer and a coating layer disposed on the Sn plating layer, and the method includes the following processes (1) to (3). Each process is described below.
• the surface-treated steel sheet in an embodiment of the present disclosure can further include a Ni-containing layer disposed below the Sn plating layer.
• a Ni-containing layer disposed below the Sn plating layer.
• the surface of a steel sheet having a Sn plating layer on at least one side is treated with an aqueous solution containing at least one of Zr ions and Ti ions to form a coating layer on the Sn plating layer.
• the formed coating layer is a coating layer containing at least one of Zr oxide and Ti oxide.
• the treatment with an aqueous solution is not limited and may be performed by any method.
• the treatment can, for example, be performed by electrolysis.
• the steel sheet with the Sn plating layer is preferably subjected to cathodic electrolysis in the aqueous solution.
• Conventional equipment used for chromating treatment or the like can be used as is for the cathodic electrolysis. Therefore, from the perspective of equipment cost reduction, the coating layer is preferably formed by cathodic electrolysis.
• the method of preparing the aqueous solution is not limited.
• the aqueous solution can be prepared by dissolving one or both of a Zr-containing compound as a Zr ion source and a Ti-containing compound as a Ti ion source in water. Distilled water or deionized water can be used as the water, but these examples are not limiting, and any water can be used.
• Zr salts such as ZrF 4 or Zr complexes such as H 2 ZrF 6 and K 2 ZrF 6 are preferably used as the Zr-containing compound.
• Zr ions become Zr oxide and form a coating.
• Ti salts such as TiF 4 or Ti complexes such as H 2 TiF 6 and K 2 TiF 6 are preferably used as the Ti-containing compound.
• Ti ions become Ti oxide and form a coating.
• the aqueous solution may further contain at least one selected from the group consisting of fluorine ions, nitrate ions, ammonium ions, phosphate ions, Mn ions, and sulfate ions.
• the treatment can be performed in a short time, from several seconds to several tens of seconds, which is extremely advantageous from an industrial standpoint.
• the aqueous solution therefore preferably contains both nitrate ions and ammonium ions in addition to at least one of Zr ions and Ti ions.
• the unit of ionic concentration "ppm" refers to parts per million unless otherwise specified.
• the aqueous solution contains Zr ions
• the concentration is preferably set to 100 ppm or more.
• the concentration is preferably set to 4000 ppm or less.
• the aqueous solution contains Ti ions
• no lower limit is placed on the concentration of the Ti ions, but the concentration is preferably set to 100 ppm or more.
• the concentration is preferably set to 4000 ppm or less.
• the aqueous solution contains fluorine ions
• the concentration is preferably set to 120 ppm or more.
• No upper limit is placed on the concentration of the fluorine ions either, but the concentration is preferably set to 4000 ppm or less.
• the aqueous solution contains phosphate ions
• no lower limit is placed on the concentration of the phosphate ions, but the concentration is preferably set to 50 ppm or more.
• No upper limit is placed on the concentration of the phosphate ions either, but the concentration is preferably set to 5000 ppm or less.
• the aqueous solution contains Mn ions
• the concentration is preferably set to 50 ppm or more.
• No upper limit is placed on the concentration of the Mn ions either, but the concentration is preferably set to 5000 ppm or less.
• the aqueous solution contains ammonium ions
• no lower limit is placed on the concentration of the ammonium ions, and the concentration may be 0 ppm.
• No upper limit is placed on the concentration of the ammonium ions either, but the concentration is preferably set to 20000 ppm or less.
• the aqueous solution contains nitrate ions
• no lower limit is placed on the concentration of the nitrate ions, and the concentration may be 0 ppm.
• No upper limit is placed on the concentration of the nitrate ions either, but the concentration is preferably set to 20000 ppm or less.
• the aqueous solution contains sulfate ions
• no lower limit is placed on the concentration of the sulfate ions
• the concentration may be 0 ppm.
• No upper limit is placed on the concentration of the sulfate ions either, but the concentration is preferably set to 20000 ppm or less.
• No upper limit is placed on the temperature of the aqueous solution during cathodic electrolysis, but the temperature is preferably set to 50 °C or lower, for example.
• Cathodic electrolysis at temperatures of 50 °C or lower enables the formation of a dense, uniform coating microstructure constituted by very fine particles.
• the temperature of the aqueous solution is preferably set to 10 °C or higher, for example.
• the efficiency of coating formation can be increased.
• the temperature of the aqueous solution is 10 °C or higher, cooling of the solution is not necessary even when the outside temperature is high, such as during the summer, which is economical.
• No lower limit is placed on the pH of the aqueous solution, but the pH is preferably set to 3 or higher. If the pH is 3 or higher, the formation efficiency of Zr oxide or Ti oxide can be further improved.
• No upper limit is placed on the pH of the aqueous solution either, but the pH is preferably set to 5 or less. A pH of 5 or less prevents the formation of large amounts of precipitation in the aqueous solution and can achieve good continuous productivity.
• Nitric acid, ammonia water, or the like, for example, may be added to the aqueous solution for the purpose of adjusting pH and improving electrolytic efficiency.
• the current pattern in the aforementioned cathodic electrolysis may be continuous current passage or intermittent current passage.
• the relationship between the aqueous solution and the steel sheet during the aforementioned cathodic electrolysis is not limited, and the solution may be relatively stationary or moving.
• cathodic electrolysis is preferably conducted while the steel sheet and the aqueous solution are moved relative to each other.
• cathodic electrolysis can be performed continuously while passing a steel sheet through a treatment tank housing an aqueous solution containing at least one of Zr ions and Ti ions, so that the steel sheet and the aqueous solution are moved relative to each other.
• the relative flow speed between the aqueous solution and the steel sheet is preferably 50 m/min or more. If the relative flow speed is 50 m/min or more, the pH of the steel sheet surface where hydrogen is generated together with current passage can be made more uniform, effectively suppressing the formation of coarse Zr oxide or Ti oxide. No upper limit is placed on the relative flow speed.
• the coating layer obtained in the coating formation process is surface conditioning. Specifically, the aqueous solution is held at 1.0 g/m 2 to 30.0 g/m 2 on a surface of the coating layer for 0.1 seconds to 20.0 seconds.
• the coating layer can be fixed in a state with a high affinity for ethylene glycol.
• the mechanism by which the surface conditioning process can fix the coating layer with a high affinity for ethylene glycol is not clear but is thought to be as follows.
• the surface of the coating layer is slightly etched, forming minute irregularities on the surface of the coating layer.
• the action of these minute irregularities improves the affinity of the coating layer for ethylene glycol.
• This affinity is different from the affinity resulting from the presence of hydrophilic functional groups, such as OH groups, and is due to the physical structure provided by the surface roughness, which also has excellent stability with respect to heat.
• the aqueous solution is preferably in the form of a liquid film from the perspective of ensuring uniform progress of etching.
• the amount of aqueous solution used for surface conditioning is 1.0 g/m 2 or less, etching does not proceed sufficiently, resulting in a contact angle of ethylene glycol that is greater than 50°.
• the amount of the aqueous solution is therefore set to 1.0 g/m 2 or more, preferably 2.0 g/m 2 or more, and more preferably 3.0 g/m 2 or more.
• the amount of the aqueous solution is greater than 30.0 g/m 2 , the affinity for ethylene glycol is reduced, resulting in a contact angle of ethylene glycol that is greater than 50°.
• the amount of the aqueous solution is therefore set to 30.0 g/m 2 or less, preferably 28.0 g/m 2 or less, and more preferably 25.0 g/m 2 or less.
• the holding time in the surface conditioning is less than 0.1 seconds, etching does not proceed sufficiently, resulting in a contact angle of ethylene glycol that is greater than 50°.
• the holding time is therefore set to 0.1 seconds or longer, preferably 0.2 seconds or longer, and more preferably 0.3 seconds or longer.
• the contact angle of ethylene glycol is also greater than 50° in a case in which the holding time exceeds 20.0 seconds. This is thought to be due to excessive etching, leading to deviation from surface conditions suitable for the development of affinity for ethylene glycol.
• the holding time is therefore set to 20.0 seconds or shorter, preferably 18.0 seconds or shorter, and more preferably 15.0 seconds or shorter.
• the amount of the aforementioned aqueous solution can be measured by a moisture meter using a filter-type infrared absorption method. Specifically, the absorbance at the surface is measured by a moisture meter using a filter-type infrared absorption method, and the amount of aqueous solution is determined from the absorbance using a previously determined calibration curve.
• the calibration curve can be prepared by the following procedures. First, a steel sheet with the above coating layer is placed on an electronic balance. The aqueous solution is dropped by pipette onto the steel sheet having the coating layer to form a liquid film over the entire surface of the steel sheet having the coating layer.
• the weight of the aqueous solution present on the steel sheet having the coating layer is determined from the weight of the steel sheet having the coating layer before the aqueous solution is dropped and the weight of the steel sheet having the coating layer after the aqueous solution is dropped.
• the resulting weight of the aqueous solution is divided by the area of the steel sheet having the coating layer to obtain the amount of aqueous solution per unit area.
• the absorbance on the surface of the steel sheet having the coating layer is measured by a moisture meter using a filter-type infrared absorption method.
• the above measurements are performed multiple times while varying the amount of aqueous solution, and a calibration curve representing the correlation between the amount of aqueous solution and absorbance is created. A linear approximation of the correlation between the amount of aqueous solution and absorbance can be used as the calibration curve.
• the method of adjusting the amount of aqueous solution present on the surface of the coating layer is not limited, and any method can be used.
• the amount of the aqueous solution on the surface of the steel sheet can be adjusted by wringing out the solution with a wringer roll or by wiping.
• the steel sheet having a Sn plating layer can optionally be pretreated.
• the pretreatment can, for example, remove a natural oxide film present on the surface of the Sn plating layer. By removal of the natural oxide film, the amount of Sn oxide can be adjusted and the surface can be activated.
• the method of the pretreatment is not limited and any method can be used, one or both of electrolytic treatment in an alkaline aqueous solution and immersion treatment in an alkaline aqueous solution are preferably performed as the pretreatment.
• electrolytic treatment in an alkaline aqueous solution and immersion treatment in an alkaline aqueous solution are preferably performed as the pretreatment.
• cathodic electrolysis and anodic electrolysis can be used as the electrolysis.
• Any of treatments (1) to (4) below is preferably performed as the pretreatment.
• the alkaline aqueous solution may contain one or more optional electrolytes. Any electrolyte may be used without limitation. Carbonate, for example, is preferably used as the electrolyte, and sodium bicarbonate is more preferably used. No lower limit is placed on the concentration of the alkaline aqueous solution, but the concentration is preferably set to 1 g/L or higher, more preferably 5 g/L or higher. No upper limit is placed on the concentration of the alkaline aqueous solution either, but the concentration is preferably set to 30 g/L or lower, more preferably 20 g/L or lower.
• No lower limit is placed on the temperature of the alkaline aqueous solution, but the temperature is preferably set to 10 °C or higher, more preferably 15 °C or higher.
• No upper limit is placed on the temperature of the alkaline aqueous solution either, but the temperature is preferably set to 70 °C or lower, more preferably 60 °C or lower.
• the electrolytic density is preferably set to 0.5 C/dm 2 or higher, more preferably 1.0 C/dm 2 or higher.
• the electrolytic density is preferably set to 10.0 C/dm 2 or less because an excessively high electrolytic density will saturate the effect of the pretreatment.
• the immersion time is preferably set to 0.1 seconds or longer, more preferably 0.5 seconds or longer.
• No upper limit is placed on the immersion time either, but the immersion time is preferably set to 10 seconds or shorter, since an excessively long immersion time will saturate the effect of the pretreatment.
• the electrolytic density is preferably set to 0.5 C/dm 2 or higher, more preferably 1.0 C/dm 2 or higher.
• the electrolytic density is preferably set to 10.0 C/dm 2 or less because an excessively high electrolytic density will saturate the effect of the pretreatment.
• water washing is preferably performed from the perspective of removing any pretreatment solution adhering to the surface.
• pretreatment is preferably performed on the base steel sheet.
• any of the above pretreatments can be performed, at least one of degreasing, pickling, and water washing is preferably performed.
• Degreasing removes rolling oil, anti-rust oil, and the like from the steel sheet.
• the degreasing is not limited and can be performed by any method. After degreasing, water washing is preferably performed to remove any degreasing treatment solution adhering to the steel sheet surface.
• Pickling removes the natural oxide film present on the surface of the steel sheet and activates the surface.
• the pickling is not limited and can be performed by any method. After pickling, water washing is preferably performed to remove any pickling treatment solution adhering to the steel sheet surface.
• the steel sheet after the surface conditioning process is subjected to water washing at least once.
• Water washing removes any residual aqueous solution from the surface of the steel sheet.
• the water washing is not limited and may be performed by any method.
• a water washing tank can be installed downstream from the tank for coating formation, and the steel sheet after the coating formation process can be continuously immersed in water. Water washing may also be performed by spraying water on the steel sheet after the coating formation process.
• any water can be used for the water washing other than the last water washing, since the above-described effect can be obtained by using water with an electrical conductivity of 100 ⁇ S/m or less for the last water washing.
• Water with an electrical conductivity of 100 ⁇ S/m or less may also be used for water washing other than the last water washing.
• water with an electrical conductivity of 100 ⁇ S/m or less is preferably used only for the last water washing, with normal water such as tap water or industrial water being used for water washing other than the last water washing.
• the temperature of water used for the water washing treatment is not limited and may be any temperature. However, since excessively high temperatures place an excessive burden on the water washing equipment, the temperature of the water used for water washing is preferably set to 95 °C or lower. No lower limit is placed on the temperature of water used for water washing either, but the temperature is preferably 0 °C or higher. The temperature of the water used in the water washing may be room temperature.
• Drying may optionally be performed after the water washing process.
• the drying method is not limited, and ordinary dryers or electric furnace drying methods, for example, can be applied.
• the temperature during the drying process is preferably 100 °C or lower. Within the aforementioned range, the transformation of the surface-treatment coating can be suppressed. Although no lower limit is placed on the temperature, the lower limit is typically around room temperature.
• surface-treated steel sheets were produced by the following procedures, and their properties were evaluated.
• the present disclosure is not, however, limited to the following examples.
• steel sheets were sequentially subjected to electrolytic degreasing, water washing, pickling by immersion in dilute sulfuric acid, and water washing, followed by Sn electroplating using a phenol sulfonic acid bath to form an Sn plating layer on both sides of the steel sheets.
• the Sn coating weight of the Sn plating layer was set at this time to the values illustrated in Tables 2 and 3 by changing the current passage time.
• the steel sheets prior to the Sn electroplating, the steel sheets were subjected to Ni electroplating using a Watts bath to form a Ni plating layer as a Ni-containing layer on both sides of the steel sheets.
• the Ni coating weight of the Ni plating layer was set at this time to the values illustrated in Tables 2 and 3 by changing the current passage time and the current density.
• the Sn coating weight of the Sn plating layer was measured by the electrolytic stripping method specified in JIS G 3303.
• the Ni coating weight of the Ni plating layer was measured by the above-described calibration curve method using X-ray fluorescence.
• the steel sheet was heated at a heating rate of 50 °C/sec by a direct current heating method for 5 seconds and then introduced into water for rapid cooling.
• a steel sheet for cans (T4 blank sheet) with a thickness of 0.17 mm was used as the steel sheet.
• the resulting Sn plating steel sheets were then subjected to the pretreatment indicated in Tables 2 and 3.
• "C” indicates cathodic electrolysis
• "A” indicates anodic electrolysis
• "D” indicates immersion treatment
• "C ⁇ A” indicates further anodic electrolysis after cathodic electrolysis.
• a sodium bicarbonate solution with a concentration of 10 g/L was used for the cathodic electrolysis, anodic electrolysis, and soaking treatment in the above pretreatment, and the temperature of the aqueous sodium bicarbonate solution was room temperature.
• the electrolytic density during the cathodic electrolysis was 2.0 C/dm 2 and the anodic electrolysis was 4.0 C/dm 2 .
• the immersion time during the immersion treatment was 1 second. For comparison, no pretreatment was performed on some of the Examples.
• the surface of the Sn plating steel sheet was treated with an aqueous solution to form a coating layer on the Sn plating layer.
• an aqueous solution with the composition illustrated in Table 1 was used as the aqueous solution, and the coating layer was formed by performing cathodic electrolysis in the aqueous solution.
• the temperature of the aqueous solution was set to 35 °C, and the pH was adjusted to be between 3 and 5.
• the Zr coating weight and Ti coating weight were controlled by adjusting the electrical density.
• Zirconium fluoride (ZrF 4 ) was used as the Zr-containing compound and titanium fluoride (TiF 4 ) as the Ti-containing compound.
• the aqueous solution was prepared by adjusting the concentration of each ion through use of additional compounds other than the Zr-containing compound and the Ti-containing compound for the aqueous solution to have the compositions illustrated in Table 1.
• surface conditioning was performed under the set of conditions illustrated in Tables 2 and 3. Specifically, at the end of the coating formation process, the steel sheet having the aqueous solution adhering to its surface was squeezed with a wringer roll to adjust the amount of aqueous solution present on the surface of the coating layer to the amounts listed in Tables 2 and 3. The amount of aqueous solution was measured by a moisture meter using a filter-type infrared absorption method, as described above. The steel sheets were then held for the holding time illustrated in Tables 2 and 3. In other words, the aqueous solution used in the surface conditioning process is the same as that used in the aforementioned coating formation process.
• water washing treatment was applied to the steel sheets after the aforementioned surface preparation process.
• the water washing treatment was performed 1 to 5 times under the set of conditions illustrated in Tables 2 and 3.
• the method of each water washing and the electrical conductivity of the water used are illustrated in Tables 2 and 3.
• the electrical conductivity was measured using a conductivity meter.
• the contact angle of ethylene glycol and the atomic ratios of adsorbed elements were measured by the following procedures for each of the obtained surface-treated steel sheets. The measurement results are listed in Tables 4 and 5.
• the contact angle was also measured after the surface-treated steel sheet was subjected to heat treatment at 200 °C for 10 minutes.
• the measurement conditions were the same as above.
• the contact angle values were substantially the same before and after heat treatment for the surface-treated steel sheets meeting the conditions of the present disclosure.
• some of the surface-treated steel sheets that did not meet the conditions of the present disclosure exhibited significant changes in contact angle values due to heat treatment.
• the total atomic ratio of K, Na, Mg, and Ca adsorbed on the surface of the surface-treated steel sheet to all elements was measured by XPS. No sputtering was performed in the measurements. From the integrated intensity of the narrow spectra of K2p, Nals, Ca2p, and Mgls at the top surface of the sample, the detected atomic ratios to all elements were quantified using the relative sensitivity factor method and calculated as (K atomic ratio + Na atomic ratio + Ca atomic ratio + Mg atomic ratio).
• the scanning X-ray photoelectron spectrometer PHI X-tool produced by ULVAC-PHI, was used, with the X-ray source being a monochrome AlK ⁇ beam, the voltage being 15 kV, the beam diameter being 100 ⁇ m ⁇ , and the take-off angle being 45°.
• BPA-free prepainted steel sheets as samples used to evaluate adhesion to a BPA-free paint were prepared according to the following procedure.
• the surface of the obtained surface-treated steel sheets was painted with a polyester-based paint for can inner surfaces (BPA-free paint) and baked at 180 °C for 10 minutes to produce BPA-free prepainted steel sheets.
• the coating weight of the paint was 60 mg/dm 2 .
• Two BPA-free prepainted steel sheets made under the same conditions were stacked so that the coated surfaces faced each other with a nylon adhesive film therebetween and were then pressure bonded under a set of conditions including a pressure of 2.94 ⁇ 10 5 Pa, a temperature of 190 °C, and a pressure bonding time of 30 seconds.
• the bonded steel sheets were then divided into 5 mm wide test pieces.
• the divided test pieces were immersed for 168 hours in a 55 °C test solution consisting of a mixed aqueous solution containing 1.5 mass% citric acid and 1.5 mass% common salt. After immersion and subsequent washing and drying, the two steel sheets of the divided test pieces were pulled apart in a tensile tester, and the tensile strength at the time of separation was measured.
• the average of three test pieces was evaluated at the following four levels. For practical purposes, a result of 1 to 3 can be evaluated as excellent adhesion to BPA-free paint.
• Table 1 Aqueous solution Composition (ppm) Zr 4+ Ti 4+ Mn 4+ PO 4 3- F NO 3 3- NH 4 + A 3000 - - - 4000 - - B 1500 - - - 2000 3000 2000 C 2000 - - 950 2000 1600 1000 D 2000 - - 950 2000 7000 2500 E 2000 2000 - 950 2000 7000 2500 F - 1500 - - 2000 3000 2000 G - 2000 - 950 2000 1600 1000 H - 2000 - 950 2000 7000 2500 I 2000 2000 2000 950 2000 7000 2500

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Materials Engineering (AREA)
• Metallurgy (AREA)
• Inorganic Chemistry (AREA)
• Mechanical Engineering (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Other Surface Treatments For Metallic Materials (AREA)
• Electroplating Methods And Accessories (AREA)
• Chemical Treatment Of Metals (AREA)
• Laminated Bodies (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=89190263

Family Applications (1)

Country Status (5)

Citations (8)

Family Cites Families (4)

• 2023
  • 2023-07-07 EP EP23894173.6A patent/EP4621095A1/en active Pending
  • 2023-07-07 JP JP2023561105A patent/JP7401039B1/ja active Active
  • 2023-07-07 CN CN202380076924.7A patent/CN120153125A/zh active Pending
  • 2023-07-07 KR KR1020257011384A patent/KR20250065872A/ko active Pending
• 2025
  • 2025-05-15 MX MX2025005778A patent/MX2025005778A/es unknown

Patent Citations (8)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events