JP2009120951A - Chromium-free resin solution composition having good alkaline resistance and forming property, method for surface treating steel sheet using the same, and surface-treated steel sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin solution composition for surface treating a steel sheet having good corrosion resistance, alkaline resistance, forming property, electrical conductivity and chemical resistance, and containing no chromium component at all, and to provide a method for producing a steel sheet using the same, and to provide a surface-treated steel sheet produced therefrom. <P>SOLUTION: The surface of a cold rolled steel sheet, a galvanized steel sheet or the like is coated with a resin solution composition containing a mixture of a soft urethane-based resin and a hard urethane-based resin, a Ti- or Zr-based organic oxide and one or more kinds of compounds selected from among aluminum monophosphate, aluminum dihydrogenphosphate, primary zinc phosphate and hydrated manganese phosphate, and a solvent at the coating weight of 300 to 1,800 mg/m<SP>2</SP>. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is particularly excellent in alkali resistance and workability, excellent in corrosion resistance, electrical conductivity and chemical resistance, and does not contain any chromium component, and a steel plate surface treatment resin solution composition, a method for producing a steel plate using the same, and This relates to the surface-treated steel sheet manufactured in this way.

  Recently, worldwide interest in environmental problems is increasing, and use restrictions on environmental pollutants, that is, Cr, Pb, Cd, Hg, PBB, PBDE, and the like are becoming strict. In particular, Guidelines for Restricting Use of Hazardous Substances Introduced by the EU (RoHS; Restriction of Hazardous Substances, '06 .7.1 Enforced), Waste Electrical and Electronic Product Disposal Guidelines (WEEE; Waste from Electrical and Electronic 7 ') .1), New Environmental Regulation Management Act (REACH; Registration, Evaluation and Authorization of Chemicals), Waste Vehicle Treatment Guidelines (ELV; End-of-Life Vehicles, '7.1.1 Enforcement), etc. This requires all companies around the world to actively respond to new environmental management policies such as the development of environmentally friendly products, the reduction of waste in factories, and green procurement. It is.

  Conventionally, corrosion resistance and resistance to galvanized steel sheets and zinc-based alloy-plated steel sheets, aluminum-plated steel sheets, aluminum-based alloy-plated steel sheets, cold-rolled steel sheets, hot-rolled steel sheets, which are used for automobile materials, home appliances, building materials, etc. In order to provide paint adhesion and the like, a surface treatment method is generally used in which a chromate film mainly composed of chromium is coated on the surface. The main chromate treatment includes electrolytic chromate and coating chromate. Among them, electrolytic chromate treatment is mainly composed of hexavalent chromium, and various anions such as sulfuric acid, phosphoric acid, boric acid and halogen are added. A method of cathodic electrolysis of a metal plate using a treatment liquid is generally performed. On the other hand, in the coating type chromate treatment, a metal plate is deposited in a treatment solution obtained by adding inorganic colloid and inorganic ions to a solution obtained by reducing a part of hexavalent chromium to trivalent in advance, or the treatment solution is applied to the metal plate. The method of spraying is generally performed.

  When such a method is used, various measures are required in the work environment and wastewater treatment due to the toxicity of hexavalent chromium contained in the chromate treatment solution, and automobiles, home appliances, and building material products using the above surface-treated metals. Recycling and disposal processes such as these also cause human harm and environmental pollution problems. In addition, when trivalent chromium is applied, there is a problem that part of the trivalent chromium is converted to hexavalent chromium depending on the ambient environment such as temperature and microorganisms.

  Therefore, each steel company is focusing on developing chromium-free surface-treated steel sheets that can satisfy various required characteristics, including corrosion resistance, alkali resistance, electrical conductivity, etc., even without hexavalent chromium. . Conventionally, a metal salt film composed mainly of phosphate is primarily coated on the surface of a steel sheet, and then a resin-based film composed mainly of acrylic, epoxy, and urethane resins is secondarily coated on the top. The surface-treated metal steel sheet not containing chromium was manufactured through a method of manufacturing the same, or a method of forming the primary coating and the secondary coating with a resin coating, respectively.

  However, since the above products often reduce the electrical conductivity and weldability of the metal steel sheet due to the metal salt or coating thickness, such as copying machines, printers, VCRs, computers, etc., to suppress electronic waves, to suppress internal noise, and to ensure workability. There is a problem that it is not suitable for the use of

  Recently, as most home appliance companies have demanded a surface-treated steel plate that has excellent electrical conductivity and does not contain chromium, the coated steel plate that does not contain chromium has been developed by a method in which the resin-based coating is coated only once. Yes. However, unless the composition of the resin-based surface treatment composition is particularly excellent, there is a problem that quality characteristics such as corrosion resistance are greatly reduced as compared with a conventional coated steel sheet treated with chromium or phosphate. However, recently, major domestic and overseas consumer electronics companies have established original quality standards for materials as a way to develop their own environmentally friendly products in the case of surface-treated steel sheets that do not contain chromium. Buy only products that earn

  Conventionally, Patent Document 1 and Patent Document 2 disclose a method of coating polyaniline on a metal plate as a coating treatment method considering electric conductivity while containing no hexavalent chromium. However, since polyaniline having high rigidity and low adhesion exists between the metal and the resin film, the film can be easily peeled off at the interface between the polyaniline and the metal and between the polyaniline and the resin. For this reason, a problem arises when the upper part is coated in order to give design properties, further corrosion resistance and other functions to the steel sheet. It is known that a film having low adhesion generally has low corrosion resistance. In addition, since the solution stability is low, precipitates are often generated, a severe odor is generated, and there is a problem that workability such as inhibition of the work environment is generally lowered. In addition, it showed excellent effects such as electrical conductivity, corrosion resistance, alkali resistance, high temperature and high humidity resistance, etc. by using the method of coating the galvanized layer only with resin, but it was processed severely. Some products applied to the parts having poor processability have a problem that the resin layer and the plating layer of the processing friction part are partially damaged and the resin layer disappears or the surface turns black.

  Further, Patent Document 3 discloses a composition in which an organic film forming material, a hexafluorocomposite such as titanium or zirconium, and at least one inorganic compound are mixed with water, but this includes a fluorine complex. It may affect the environment, and the solution is acidic and care must be taken during handling. Patent Document 4 discloses a composition in which a mixed resin is mixed with a vanadium compound and Zi, Ti, and the like. However, the reduction of the vanadium compound and the adhesion of the steel plate surface using an acidic solution to ensure adhesion are disclosed. There is a problem that must be accompanied by an etching process. Further, Patent Document 5 discloses a surface treatment composition comprising an organic resin and an inorganic binder composite using a silane coupling agent or the like and containing a rust inhibitor and a metal chelating agent. There is a disadvantage that the binder composite must be manufactured in advance. In addition, some products that require alkali resistance have poor alkali resistance, and there is a problem that the resin layer is partially damaged when contacted with an alkaline solution and the resin layer disappears or the surface is severely discolored. Patent Document 6 discloses a resin composition containing an organic resin and a phosphoric acid compound selected from ammonium phosphate, sodium phosphate, and potassium phosphate. It is limited that it has a role of improving the corrosion resistance by forming a passive film layer.

Japanese Unexamined Patent Publication No. 8-92479 Japanese Unexamined Patent Publication No. 8-500770 US Published Patent No. 2004-54044 Japanese Published Patent No. 2002-030460 Korean Published Patent No. 2006-76953 Japanese Patent No. 3706518

  One object of the present invention is to improve the alkali resistance and workability through a method of coating a steel sheet with a resin solution composition, and is excellent in corrosion resistance, electrical conductivity, chemical resistance, etc., and does not contain chromium. It is to provide a metal surface treatment composition capable of providing a layer.

  Another object of the present invention is to provide a surface-treated steel sheet coated with the surface treatment composition of the metal steel sheet.

  Still another object of the present invention is to provide a method for producing a surface-treated steel sheet by forming a coating layer of a resin solution with the resin solution composition according to the present invention.

  The object of the present invention is not limited to the contents described above, and can be clearly understood by those skilled in the art from the following description.

  In order to achieve the above object, in the present invention, a resin solution composition applied on a steel plate and / or a galvanized layer, a method for producing a surface-treated steel plate using the same, and a surface-treated steel plate produced by the above method Is to provide.

  As the first aspect of the present invention, the mixed urethane resin of soft urethane resin and hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, first A resin solution composition for surface treatment of a steel sheet, comprising at least one compound selected from the group consisting of zinc phosphate and hydrated manganese phosphate and a solvent.

  As a second aspect, mixed urethane resin of soft urethane resin and hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate and hydration A mixture of at least one compound selected from the group consisting of manganese phosphate and a solvent, and based on the solid content weight of the total resin solution composition, 10 to 90% by weight of the mixed urethane resin and Ti or Zr-based organic oxidation 1 to 20% by weight of a product, and 0.1 to 10.0% by weight of a compound selected from the group consisting of single aluminum phosphate, aluminum dihydrogen phosphate, primary zinc phosphate, and hydrated manganese phosphate It is the resin solution composition for surface treatment of a steel plate.

  As a third aspect, the mixed urethane resin is a resin solution composition for surface treatment of a steel sheet, which is composed of 5 to 95% by weight of a soft urethane resin and 5 to 95% by weight of a hard urethane resin.

  As a fourth aspect, the soft urethane-based resin is a polyurethane produced from isophorene diisocyanate, adipic acid and a polyhydric alcohol, or a polyurethane produced from an acrylic polyol and a polyisocyanate. It is a thing.

  In a fifth aspect, the polyhydric alcohol is a resin solution composition for surface treatment of a steel sheet selected from acrylic polyol, polyester polyol, polyether polyol, polyolefin polyol, or a mixture thereof.

  As a sixth aspect, the soft urethane-based resin is a resin solution composition for surface treatment of a steel sheet having a number average molecular weight of 5,000 to 300,000.

  According to a seventh aspect, the hard urethane resin is a polyurethane resin produced from polycaprolactone polyol or polycarbonate polyol and diisocyanate, 4,4′-bis (ω-hydroxyalkyleneoxy) biphenyl and methyl-2,6-diisocyanate hexa A resin solution composition for surface treatment of a steel sheet, selected from a polyurethane resin produced from noate and a polyurethane resin having an acetal bond.

  As an eighth aspect, the hard urethane resin is a resin solution composition for surface treatment of a steel sheet having a number average molecular weight of 200,000 to 2,000,000.

  As a ninth aspect, the hard urethane resin is a resin solution composition for surface treatment of a steel sheet having a Shore A hardness of 40 to 90.

  In a tenth aspect, the diisocyanate is a resin solution composition for surface treatment of a steel sheet, which is paraphenylene diisocyanate.

  In an eleventh aspect, the Ti or Zr-based organic oxide is composed of titanium diisopropoxide bis (acetylacetonate), titanium orthoester, titanium (IV) butoxide, titanium (IV) (triethanolaminato) isopropoxide. , Tetrakis (triethanolaminato) zirconium (IV), titanium (IV) 2-ethylhexoxide, titanium (IV) isopropoxide, zirconium (IV) bis (diethylcitrate) -dipropoxide or mixtures thereof It is the resin solution composition for surface treatment of a steel plate.

  As a twelfth aspect, the resin solution composition for surface treatment of steel sheets, wherein the solvent is water.

  As a thirteenth aspect, the solvent is an alcohol solvent selected from ethanol, methanol, propanol, isopropanol and glycerol, an amine compound, N-methylpyrrolidone, sodium hydroxide, potassium hydroxide, sodium carbonate and ammonium hydroxide. A resin solution composition for surface treatment of a steel sheet, further comprising an aqueous solution or a mixture thereof.

  As a fourteenth aspect, there is provided a resin solution composition for surface treatment of a steel sheet, further comprising at least one or more additives selected from a wetting agent, a crosslinking agent, a lubricant and an antifoaming agent.

As a fifteenth aspect, from a mixed urethane resin of soft urethane resin and hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, zinc zinc phosphate and hydrated manganese phosphate A steel sheet surface treatment method including a step of coating a resin solution composition containing at least one compound selected from the group and a solvent on an upper surface of the steel sheet with an adhesion amount of 300 to 1,800 mg / m ² after drying.

As a sixteenth aspect, mixed urethane resin of soft urethane resin and hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate and hydrated phosphorus Coating the resin solution composition containing at least one compound selected from the group consisting of manganese acid and a solvent on the upper part of the steel sheet with an adhesion amount of 300 to 1,800 mg / m ² after drying, Based on the solid content weight of the solution composition, mixed urethane resin 10 to 90% by weight, Ti or Zr organic oxide 1 to 20% by weight, single aluminum phosphate, aluminum dihydrogen phosphate, first phosphorus A surface treatment method for a steel sheet comprising 0.1 to 10.0% by weight of at least one compound selected from the group consisting of zinc oxide and hydrated manganese phosphate .

  According to a seventeenth aspect, the mixed urethane resin is a steel sheet surface treatment method comprising 5 to 95% by weight of a soft urethane resin and 5 to 95% by weight of a hard urethane resin.

  An eighteenth aspect is a method for producing a surface-treated steel sheet, further comprising a step of drying a steel sheet coated with the resin solution composition at a PMT of 80 to 200 ° C.

  As a nineteenth aspect, the steel sheet is a cold-rolled steel sheet, a galvanized steel sheet, a zinc-based electroplated steel sheet, a hot-dip galvanized steel sheet, an aluminum-plated steel sheet, a plated layer of cobalt, molybdenum, tungsten, nickel, titanium, aluminum, manganese, iron, Plated steel sheet containing impurities or dissimilar metals such as magnesium, tin, copper, or a mixture thereof, aluminum alloy sheet with addition of silicon, copper, magnesium, iron, manganese, titanium, zinc or a mixture thereof, and phosphate coating It is the surface treatment method of the steel plate selected from the group which consists of a galvanized steel plate, a cold-rolled steel plate, and a hot-rolled steel plate.

  According to a twentieth aspect, the soft urethane-based resin has a number average molecular weight of 5,000 to 300,000 and is produced from isophorene diisocyanate, adipic acid and a polyhydric alcohol.

  According to a twenty-first aspect, the rigid urethane resin has a number average molecular weight of 200,000 to 2,000,000 and is a polyurethane resin produced from polycaprolactone polyol or polycarbonate polyol and paraphenylene diisocyanate, 4,4′-bis. This is a steel sheet surface treatment method selected from a polyurethane resin produced from (ω-hydroxyalkyleneoxy) biphenyl and methyl-2,6-diisocyanatohexanoate and a polyurethane resin having an acetal bond.

  According to a twenty-second aspect, the hard urethane resin is a steel sheet surface treatment method having a Shore A hardness of 40 to 90.

  As a twenty-third aspect, Ti or Zr-based organic oxides are titanium diisopropoxide bis (acetylacetonate), titanium orthoester, titanium (IV) butoxide, titanium (IV) (triethanolaminato) isopropoxide, Selected from tetrakis (triethanolaminato) zirconium (IV), titanium (IV) 2-ethylhexoxide, titanium (IV) isopropoxide, zirconium (IV) bis (diethylcitrate) -dipropoxide or mixtures thereof This is a surface treatment method of a steel sheet.

  According to a twenty-fourth aspect, there is provided a steel sheet surface treatment method, wherein the solvent is water.

  According to a 25th aspect, the solvent is an alcohol solvent selected from ethanol, methanol, propanol, isopropanol and glycerol, an amine compound, N-methylpyrrolidone, sodium hydroxide, potassium hydroxide, sodium carbonate and ammonium hydroxide. It is the surface treatment method of the steel plate which further contains aqueous solution or these mixtures.

As a twenty-sixth aspect, a coating layer of a steel plate and a resin solution is formed, and the coating layer of the resin solution includes a mixture of a soft urethane resin and a hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, The amount of adhesion after drying a resin solution composition containing at least one compound selected from the group consisting of aluminum dihydrogen phosphate, primary zinc phosphate and hydrated manganese phosphate and a solvent on the upper part of the steel sheet is 300 to It is a surface-treated steel sheet coated with 1,800 mg / m ² .

As a twenty-seventh aspect, a coating layer of a steel plate and a resin solution is formed. The coating layer of the resin solution includes a mixture of a soft urethane resin and a hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, The amount of urethane resin includes at least one compound selected from the group consisting of aluminum dihydrogen phosphate, primary zinc phosphate, and hydrated manganese phosphate, and a solvent, based on the solid content of the entire solution composition. 10 to 90% of 5 to 95% by weight of soft urethane resin and 5 to 95% by weight of hard urethane resin, 1 to 20% by weight of Ti or Zr organic oxide, single aluminum phosphate, phosphoric acid At least one compound selected from the group consisting of aluminum dihydrogen, primary zinc phosphate and hydrated manganese phosphate is 0.1 to 10.0% by weight There resin solution composition was coated in coating weight 300 to 1,800 mg / m ² after drying on top of the steel sheet, surface-treated steel sheet is provided.

  As described above, the metal surface treatment composition and the surface-treated steel sheet having a coating layer that does not contain a chromium component and has excellent alkali resistance and corrosion resistance according to the present invention are workability, electrical conductivity, water deterioration resistance, and solution stability. It has excellent properties and can be easily used as a processing material for customers.

  Hereinafter, the present invention will be described in detail.

  The present invention relates to a mixture of a soft urethane resin and a hard urethane resin, a corrosion-resistant curing agent composed of Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate and water. By coating a plated or unplated steel plate with a chromium-free resin solution composition composed of at least one compound selected from the group consisting of Japanese manganese phosphate and a solvent, The present invention relates to a resin solution composition for surface treatment which can improve the workability and can produce a metal steel plate having excellent electrical conductivity, corrosion resistance, chemical resistance and the like.

  In the resin solution composition of the present invention, a mixed urethane resin of the soft urethane resin and the hard urethane resin is used. However, the urethane resin is strong in water resistance, chemical resistance, acid resistance and alkali resistance, and has a coating film. Because it is soft but strong, it is widely used to coat steel plates, aluminum plates, etc. to prevent scratches on the surface, or to give chemical resistance.

  The mixed urethane resin has a solid content concentration of 10 to 90% by weight based on the solid content of the entire resin solution composition. If the solid content of the entire urethane-based resin is less than 10% by weight, the salt water resistance of the urethane resin against penetration of corrosion ions and the chemical resistance against penetration of chemical substances are not exhibited, and the chemical resistance and alkali resistance are reduced. The As a result, when degreasing at 60 ° C. for 5 minutes with an alkaline solution having a pH of 10 or more, there is a problem that the resin coating is discolored or peeled off. Has the disadvantage of rising.

  However, since the urethane resin alone has a limit in realizing a strong property while being soft, in the present invention, a mixed urethane resin in which a soft urethane resin and a hard urethane resin are mixed is used. The soft urethane resin is 5 to 95% by weight based on the solid content concentration of the mixed urethane resin. If the solid content concentration of the soft urethane resin is less than 5% by weight, the workability is improved, but the heat resistance and water deterioration resistance are reduced, and if it exceeds 95% by weight, the workability is not improved and the corrosion resistance is large. There is a problem of being lowered.

  The molecular weight of the soft urethane resin is preferably 5,000 to 300,000. If the molecular weight of the soft urethane resin is less than 5,000, the processability is greatly reduced, and if it exceeds 300,000, the stability of the solution decreases.

  The soft urethane-based resin is a polyurethane resin produced from isophorene diisocyanate, adipic acid and polyhydric alcohol such as polyurethane dispersion resin, polyethylene-modified polyurethane resin, etc., acrylic-urethane resin, polyethylene-acryl-modified polyurethane resin, etc. A polyurethane resin produced from such an acrylic polyol and a polyisocyanate can be used. Here, as the polyhydric alcohol, acrylic polyol, polyester polyol, polyether polyol, polyolefin polyol, or the like can be used.

  The molecular weight of the hard urethane resin is preferably 200,000 to 2,000,000. If the molecular weight of the hard urethane resin is less than 200,000, there is no effect of improving processability, and if it exceeds 2,000,000, the stability of the solution decreases, and the viscosity of the resin solution increases, so There is a problem that decreases.

  The hard urethane resin is a polyurethane resin produced from polycaprolactone polyol or polycarbonate polyol and isocyanate, particularly paraphenylene diisocyanate, 4,4′-bis (ω-hydroxyalkyleneoxy) biphenyl and methyl-2,6- A polyurethane resin produced from diisocyanate hexanoate, a polyurethane resin having an acetal bond, or the like can be used.

  The hard urethane resin preferably has a Shore A hardness of 40 to 90 when a dry film is produced. If the Shore A hardness is less than 40, there is no effect in improving the workability, and if the Shore A hardness exceeds 90, the coating film becomes very hard and is crushed during processing, so there is no effect in improving the workability. It is preferable to have a hardness in the range.

  Ti or Zr organic oxide is added to the urethane resin as a corrosion-resistant curing agent. The corrosion-resistant curing agent is 1 to 20% by weight based on the solid content of the entire resin solution composition. At this time, if the content of the corrosion-resistant curing agent is less than 1% by weight, the corrosion resistance is lowered and there is almost no effect of addition, and if it exceeds 20% by weight, the concentration is saturated and a large amount of precipitates are generated, resulting in solution stability. There is a problem that the corrosion resistance, alkali resistance and water deterioration resistance decrease while being lowered.

  Preferred examples of the Ti or Zr organic oxide include titanium diisopropoxide bis (acetylacetonate), titanium orthoester, titanium (IV) butoxide, titanium (IV) (triethanolaminato) isopropoxide. , Tetrakis (triethanolaminato) zirconium (IV), titanium (IV) 2-ethylhexoxide, titanium (IV) isopropoxide, zirconium (IV) bis (diethylcitrate) -dipropoxide, and the like. And at least one compound selected from these.

  Further, the resin composition for surface treatment of a steel sheet of the present invention comprises a compound selected from one or more of single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate, hydrated manganese phosphate, and the like. Including. Such a compound is added to improve the adhesion between the resin and the steel sheet, particularly the galvanized layer, and a passive film is formed on the upper part of the zinc layer to improve corrosion resistance. The effect of improving heat resistance can be expected.

  Compounds such as single aluminum phosphate, aluminum dihydrogen phosphate, primary zinc phosphate, and hydrated manganese phosphate are preferably added in an amount of 0.1 to 10.0% by weight based on the total solid content of the resin composition. When these compounds are added at less than 0.1% by weight, the adhesion to the steel sheet is reduced, and the resin is liable to be peeled off in a process such as alkaline degreasing. By improving the adhesion strength of the resin, the phenomenon of resin condensation is promoted and the solution stability is lowered, and the adhesion strength between the resin and the steel sheet is lowered, which is not preferable.

  The component obtained by removing the solid content from the resin solution composition is a solvent, and water can be used as the solvent. Furthermore, in order to improve the wettability and dispersibility of the coating composition, a separate alcohol solvent and an alkaline aqueous solution can be further added. As the alcohol solvent, ethanol, methanol, propanol, isopropanol, glycerol or the like can be used. As the alkaline aqueous solution, an amine compound, N-methylpyrrolidone, sodium hydroxide, potassium hydroxide, sodium carbonate, ammonium hydroxide can be used. Etc. can be used.

  In the resin solution composition, since the particles of the corrosion-resistant curing agent are uniformly reacted and dispersed with the organic functional group of the resin, the resin solution has excellent stability and corrosion resistance, electrical conductivity, and alkali resistance of the anticorrosion coating layer. Further, high temperature and high humidity resistance and the like are further improved.

  Further, the surface treatment composition of the present invention may further contain one or more additives such as a wetting agent, a crosslinking agent, a lubricant, and an antifoaming agent. The above wetting agent is effective in further improving the stripe pattern and adhesion, the cross-linking agent is in corrosion resistance and alkali resistance, the lubricant is in friction coefficient and workability, and the antifoaming agent is further effective in improving workability. These additives are preferably used in an amount of 5 to 25% by weight based on the solid content of the resin solution composition. If the content of the additive is less than 5% by weight, the effect of using the additive such as corrosion resistance and alkali resistance is not shown. If the content exceeds 25% by weight, the effect is saturated, and addition beyond that is meaningless, and solution stability There is a problem of reducing.

  Examples of the wetting agent include a deagglomeration type wetting and dispersing agent, a polymer type wetting and dispersing agent, and preferred examples thereof include a wetting and dispersing agent commercially available from EFKA and Tego, etc., and EFKA3580 (Ciba). , BW-W500 (BUHMWOO Chemical) or WET500 (Ciba).

  As the crosslinking agent, vinyl silane, methoxy silane, acrylic silane, epoxy silane, chloro silane, alkoxy silane, silazane, silylating agent, melamine, melamine resin, alkyl melamine, alkyl melamine resin, fluorinated melamine and fluorinated melamine resin, polyamine series An alkylated aromatic polyamine, polyamide, or acid anhydride curing agent can be used.

  Examples of the lubricant include silicon wax, polyethylene wax, polypropylene wax, amide wax, polytetrafluoroethylene (PTFE) wax, and paraffin wax.

  As the antifoaming agent, an oil type, a modified oil type, a solution type, a powder type, or an emulsion type silicon antifoaming agent can be used.

The adhesion amount of the coating layer coated with the resin solution composition of the present invention is preferably 300 to 1,800 mg / m ² as the adhesion amount after drying, and the drying temperature (PMT) is the usual resin surface treatment liquid. It is 80 ° C. to 200 ° C. similar to the drying temperature. At this time, if the adhesion amount after drying is less than 300 mg / m ² , there is no effect of improving corrosion resistance and workability, and if it exceeds 1,800 mg / m ² , the effect on corrosion resistance is saturated and the electrical conductivity is lost. Economics decrease due to price increases. Moreover, although the corrosion resistance of the resin film tends to be improved as the drying temperature is higher, the quality required by the customer can be satisfied at 80 to 200 ° C.

  In addition, as a metal plate to which the present invention can be applied, zinc-based steel such as galvanized steel sheet, zinc-nickel plated steel sheet, galvanized iron-plated steel sheet, zinc-titanium-plated steel sheet, zinc-magnesium-plated steel sheet, zinc-manganese-plated steel sheet, and zinc-aluminum-plated steel sheet Electroplated steel sheet, hot-dip steel sheet, aluminum-plated steel sheet, and these plated layers include, for example, cobalt, molybdenum, tungsten, nickel, titanium, aluminum, manganese, iron, magnesium, tin, copper, etc. as different metals or impurities Plated steel sheets, plated steel sheets in which inorganic substances such as silica and alumina are dispersed in these plated layers, or aluminum alloy sheets added with silicon, copper, magnesium, iron, manganese, titanium, zinc, etc., or phosphate are applied Galvanized steel sheet, cold rolled steel sheet, heat Is a steel plate or the like. Further, the present invention can be applied to a multilayer plating plate in which two or more kinds are sequentially processed during the above plating.

Hereinafter, the present invention will be described in more detail through examples. However, the present invention is not limited to the following examples.
[Example 1-13 and Comparative Example 1-14]
(1-1. Production of resin solution composition)

  A urethane resin having a number average molecular weight of 100,000, which is composed of isophorene diisocyanate, adipic acid, and a polyhydric alcohol monomer as a monomer of the soft urethane resin was produced. An acrylic resin having a number average molecular weight of 1,000,000 was produced from paraphenylene diisocyanate and a polycarbonate polyol monomer as monomers of a hard urethane resin. A Ti organic oxide (trade name Tyzor TE (registered trademark) titanium (IV) (triethanolaminato) isopropoxide) manufactured by Dupont was used as a corrosion-resistant curing agent. As the aluminum phosphate, pure chemical aluminum dihydrogen phosphate was used. At this time, the contents of soft urethane resin and hard urethane resin, Ti corrosion-resistant curing agent, aluminum dihydrogen phosphate and other additives were adjusted as shown in Table 1 to evaluate the quality characteristics.

Examples of the additive include colloidal silica (Nissan chemical, Snowtex-40) 10% by weight, siloxane-based wetting agent (Ciba EFKA 3580) 0.5% by weight, silane-based cross-linking material (Aldrich, 3-glycidoxypropyl). Trimethoxysilane (1.2% by weight), amine-based curing agent (Cytec Corp. Cymel 303) 2.5% by weight, and polyethylene-based lubricant (Noveon Lanco PE 1500) 1.5% by weight were added in bulk. The solid content of the surface treatment composition was adjusted to about 15% by weight. For reference, water was used as the remaining main component excluding the solid content, and about 3% by weight of ethanol was added as an alcohol solvent, and about 0.5% by weight of an amine compound was added as an alkaline aqueous solution.
(1-2. Production of coated steel sheet)

1) Specimen: An electrogalvanized steel sheet (EG) having an adhesion amount of 20 g / m ^{2 on} one side as a raw steel sheet for applying the surface treatment composition was used.
2) Application method: The resin solution was applied to the top of the sample using a continuous Roll Coating simulator, and dried at 180 ° C. PMT. The adhesion amount of the film was 1,000 mg / m ² .
(1-3. Performance evaluation method)

(1) Workability: After measuring the coefficient of friction using a draw bead friction tester (load 1,000 kgf, speed 1,000 mm / min, distance 100 mm), the resin film of the specimen is placed on the bead surface of the friction tester. The degree of catching damage was evaluated according to the following criteria.
○: Damage area less than 5% Δ: Damage area 5% or more, less than 10% ×: Damage area 10% or more

(2) Corrosion resistance: The specimen was subjected to a salt spray test in accordance with JIS-Z2371 for 96 hours, and the degree of rusting was evaluated according to the following criteria.
○: White rust 5% or less △: White rust 5% or more, less than 20% ×: White rust 20% or more

(3) Electrical conductivity: The surface of a specimen coated with a resin film was measured by surface resistance measurement (Loresta-GP) and evaluated according to the following criteria.
○: Surface resistance 1 mΩ or less △: Surface resistance 1Ω or less ×: Surface resistance is more than 1Ω and electrical conductivity or weldability is very poor

(4) Alkali resistance: Deposited in an alkali solution (Gardoclean 4292L, pH 12) at 50 ° C. for 5 minutes, washed with water, then observed for changes in color difference and peeling of the resin coating layer with the naked eye and evaluated according to the following criteria.
○: No peeling, color difference change 2.0 or less Δ: No peeling but color difference change 2.0 excess x: Peeling occurred

(5) Water deterioration resistance: After being immersed in water for 30 minutes and then rubbed back and forth 30 times with a finger, the color difference was measured and evaluated according to the following criteria.
○: Color difference of 1.0 or less Δ: Color difference of more than 1.0 ×: Peeling occurred

(6) Solution stability: 100 g of the surface treatment composition was left in a 50 ° C. oven, and after 10 days had passed, the degree of occurrence of solution precipitation, gelation and separation phenomenon was evaluated according to the following criteria.
○: No precipitation, gelation, or separation phenomenon Δ: One of precipitation, gelation, or separation phenomenon occurs finely ×: One or more of precipitation, gelation, or separation phenomenon occurs to some extent

  The evaluation results are shown in Table 1 below.

[Examples 14-19 and Comparative Examples 15-17]
(2-1. Production of coated steel sheet)

1) Specimen: An electrogalvanized steel sheet (EG) that is a raw steel sheet for applying the surface treatment composition and has an adhesion amount of 20 g / m ^{2 on} one side.
2) Coating method: In the coating of the pretreatment solution of the example, the specimen was immersed in the pretreatment solution for 3 seconds and then dried under the PMT conditions as shown in Table 2.
Moreover, the resin solution was manufactured with the composition of Example 4 in Table 1, and the resin solution composition was applied to the upper part of the steel plate using a continuous Roll Coating simulator, and dried under the adhesion amount and PMT conditions as shown in Table 2.
(2-3. Performance evaluation method)

The processability, electrical conductivity, and corrosion resistance of the specimens manufactured under the above conditions were evaluated using the evaluation methods shown in [Table 1].
(2-4. Evaluation results)

  The performance of the metal surface treatment composition was evaluated under the above conditions and is shown in Table 2.

  As shown in Table 2, the surface-treated steel sheets of Examples 14 to 19 according to the present invention showed excellent quality characteristics, while Comparative Examples 17 to 19 showed deteriorated characteristics.

1 is a schematic structural diagram of a steel plate manufactured by applying a coating layer of a resin solution in an example of the present invention. It is the figure which compared the grade of the surface damage after evaluating the processing characteristic of one Example of this invention, and the existing invention material with a draw bead friction tester. It is the figure which compared the grade of the surface external appearance after evaluating the alkali resistance characteristic of one Example of this invention, and the existing invention material with a degreasing solution.

Claims (27)

  A group consisting of a mixed urethane resin of a soft urethane resin and a hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate, and hydrated manganese phosphate A resin solution composition for surface treatment of a steel sheet, comprising at least one compound selected from: and a solvent.   A group consisting of a mixed urethane resin of a soft urethane resin and a hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate, and hydrated manganese phosphate The mixed urethane resin is 10 to 90% by weight and the Ti or Zr organic oxide is 1 to 20% by weight based on the solid content weight of the entire resin solution composition. And a resin for surface treatment of a steel sheet, comprising 0.1 to 10.0% by weight of a compound selected from the group consisting of single aluminum phosphate, aluminum dihydrogen phosphate, primary zinc phosphate and hydrated manganese phosphate Solution composition.   The resin solution composition for surface treatment of a steel sheet according to claim 2, wherein the mixed urethane resin is composed of 5 to 95 wt% of a soft urethane resin and 5 to 95 wt% of a hard urethane resin.   The said soft urethane type resin is the polyurethane manufactured from an isophorene diisocyanate, adipic acid, and a polyhydric alcohol, or the polyurethane manufactured from an acryl polyol and a polyisocyanate. Resin solution composition for surface treatment of steel sheets.   The resin solution composition for surface treatment of a steel sheet according to claim 4, wherein the polyhydric alcohol is selected from an acrylic polyol, a polyester polyol, a polyether polyol, a polyolefin polyol, or a mixture thereof.   The resin solution composition for surface treatment of a steel sheet according to claim 4, wherein the soft urethane resin has a number average molecular weight of 5,000 to 300,000.   The rigid urethane resin is a polyurethane resin produced from polycaprolactone polyol or polycarbonate polyol and diisocyanate, 4,4′-bis (ω-hydroxyalkyleneoxy) biphenyl and methyl-2,6-diisocyanate hexanoate. The resin solution composition for surface treatment of a steel sheet according to any one of claims 1 to 3, selected from a polyurethane resin to be produced and a polyurethane resin having an acetal bond.   The resin solution composition for surface treatment of a steel sheet according to claim 7, wherein the hard urethane resin has a number average molecular weight of 200,000 to 2,000,000.   The resin solution composition for surface treatment of a steel sheet according to claim 7, wherein the hard urethane resin has a Shore A hardness of 40 to 90.   The resin solution composition for surface treatment of a steel sheet according to claim 7, wherein the diisocyanate is paraphenylene diisocyanate.   The Ti or Zr organic oxides are titanium diisopropoxide bis (acetylacetonate), titanium orthoester, titanium (IV) butoxide, titanium (IV) (triethanolaminato) isopropoxide, tetrakis (triethanol). 2. Aminato) zirconium (IV), titanium (IV) 2-ethylhexoxide, titanium (IV) isopropoxide, zirconium (IV) bis (diethylcitrate) -dipropoxide or mixtures thereof. The resin solution composition for surface treatment of the steel plate according to any one of claims 3 to 3.   The resin solution composition for surface treatment of a steel sheet according to any one of claims 1 to 3, wherein the solvent is water.   The solvent is an alcoholic solvent selected from ethanol, methanol, propanol, isopropanol and glycerol, an amine compound, N-methylpyrrolidone, sodium hydroxide, potassium hydroxide, sodium carbonate and ammonium hydroxide, or an aqueous solution of these. The resin solution composition for surface treatment of a steel sheet according to claim 12, further comprising a mixture.   The resin solution composition for surface treatment of a steel sheet according to any one of claims 1 to 3, further comprising at least one of additives selected from a wetting agent, a crosslinking agent, a lubricant, and an antifoaming agent. Selected from the group consisting of mixed urethane resin of soft urethane resin and hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate and hydrated manganese phosphate A method for treating the surface of a steel sheet, comprising a step of coating a resin solution composition containing at least one compound and a solvent on an upper portion of the steel sheet with an adhesion amount of 300 to 1,800 mg / m ² after drying. A group consisting of a mixed urethane resin of a soft urethane resin and a hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate, and hydrated manganese phosphate Coating the resin solution composition containing at least one compound selected from the above and a solvent on the upper part of the steel sheet with an adhesion amount of 300 to 1,800 mg / m ² after drying, and solidifying the whole resin solution composition Based on the part weight, mixed urethane resin 10 to 90% by weight, Ti or Zr organic oxide 1 to 20% by weight, single aluminum phosphate, aluminum dihydrogen phosphate, first zinc phosphate and hydration A method for treating a surface of a steel sheet, comprising 0.1 to 10.0% by weight of at least one compound selected from the group consisting of manganese phosphate.   The steel sheet surface treatment method according to claim 16, wherein the mixed urethane resin is composed of 5 to 95 wt% of a soft urethane resin and 5 to 95 wt% of a hard urethane resin.   The steel sheet surface treatment method according to any one of claims 15 to 17, further comprising a step of drying the steel sheet coated with the resin solution composition at a PMT of 80 to 200 ° C.   The steel sheet is cold-rolled steel sheet, galvanized steel sheet, zinc-based electroplated steel sheet, hot-dip galvanized steel sheet, aluminum-plated steel sheet, plating layer with cobalt, molybdenum, tungsten, nickel, titanium, aluminum, manganese, iron, magnesium, tin, copper Alternatively, a plated steel sheet containing impurities or different metals, a mixture thereof, silicon, copper, magnesium, iron, manganese, titanium, zinc or an aluminum alloy sheet added with a mixture thereof, a galvanized steel sheet coated with phosphate The surface treatment method for a steel sheet according to any one of claims 15 to 17, which is selected from the group consisting of a cold-rolled steel sheet and a hot-rolled steel sheet.   The soft urethane resin is a polyurethane having a number average molecular weight of 5,000 to 300,000 and manufactured from isophorene diisocyanate, adipic acid and a polyhydric alcohol, or a polyurethane manufactured from an acrylic polyol and a polyisocyanate. A surface treatment method for a steel sheet according to any one of claims 15 to 17.   The hard urethane resin has a number average molecular weight of 200,000 to 2,000,000 and is a polyurethane resin produced from polycaprolactone polyol or polycarbonate polyol and paraphenylene diisocyanate, 4,4′-bis (ω-hydroxyl). The surface of the steel plate according to any one of claims 15 to 17, which is selected from a polyurethane resin produced from (alkyleneoxy) biphenyl and methyl-2,6-diisocyanatohexanoate and a polyurethane resin having an acetal bond. Processing method.   The steel sheet surface treatment method according to claim 21, wherein the hard urethane resin has a Shore A hardness of 40 to 90.   The Ti or Zr organic oxides are titanium diisopropoxide bis (acetylacetonate), titanium orthoester, titanium (IV) butoxide, titanium (IV) (triethanolaminato) isopropoxide, tetrakis (triethanol). 16. Aminato) zirconium (IV), titanium (IV) 2-ethylhexoxide, titanium (IV) isopropoxide, zirconium (IV) bis (diethylcitrate) -dipropoxide or mixtures thereof. The steel plate surface treatment method according to claim 17.   The steel sheet surface treatment method according to claim 15, wherein the solvent is water.   The solvent is an alcoholic solvent selected from ethanol, methanol, propanol, isopropanol and glycerol, an amine compound, N-methylpyrrolidone, sodium hydroxide, potassium hydroxide, sodium carbonate and ammonium hydroxide, or an aqueous mixture thereof. The steel plate surface treatment method according to claim 24, further comprising: It consists of a steel plate and a resin solution coating layer, the resin solution coating layer comprising a mixture of soft urethane resin and hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate A resin solution composition containing at least one compound selected from the group consisting of first zinc phosphate and hydrated manganese phosphate and a solvent is attached to the upper part of the steel sheet in an amount of 300 to 1,800 mg / Surface treated steel sheet coated with m ² . It consists of a steel plate and a resin solution coating layer, the resin solution coating layer comprising a mixture of soft urethane resin and hard urethane resin, Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate The amount of the urethane resin includes at least one compound selected from the group consisting of primary zinc phosphate and hydrated manganese phosphate and a solvent, and the amount of the urethane resin based on the solid content of the whole solution composition is 5 10 to 90% by weight of 95 to 95% by weight and 5 to 95% by weight of a hard urethane resin, 1 to 20% by weight of Ti or Zr organic oxide, single aluminum phosphate, aluminum dihydrogen phosphate, A resin solution in which at least one compound selected from the group consisting of primary zinc phosphate and hydrated manganese phosphate is 0.1 to 10.0% by weight Narubutsu were coated with coating weight 300 to 1,800 mg / ^{m 2} after drying on top of steel sheet, surface-treated steel sheet.