TWI621526B - Resin coated zinc plated metal sheet - Google Patents

Abstract

The present invention provides a resin-coated zinc-plated metal sheet excellent in corrosion resistance, abrasion resistance, and blackening resistance. The resin-coated zinc-plated metal plate of the present invention is applied to at least one side of a metal plate coated with a zinc plating layer, and has a laminated film thickness of 0.2 μm or more, and the film thickness is laminated on the first layer. The second layer of 0.2 μm or more is characterized in that the first layer is in a total mass of 100% by mass of the resin component and the colloidal cerium oxide, the resin component is 70 to 95% by mass, and the colloidal cerium oxide is 5 to 30% by mass. % of the resin composition is formed, and the second layer is composed of 100% by mass of the total of the resin component, the colloidal cerium oxide and the thixotropic agent, the resin component is 14 to 49.95 mass%, and the colloidal cerium oxide is 50 to 80 mass. %, the thixotropic agent is formed in a resin composition of 0.05 to 6% by mass.

Description

Resin coated zinc plated metal sheet

The present invention relates to a resin-coated zinc-plated metal sheet which is used for a casing or a built-in part of a home electronic product, an exterior part, a steel piece, or the like, or a building material or the like.

In the past, zinc-plated metal sheets have been widely used for electronic components, exterior parts, and interior parts. Among them, a zinc-plated metal sheet in which a resin coating film for imparting corrosion resistance is laminated is used (for example, Patent Document 1). However, zinc plating is soft in the metal, and the coating film having a high content of the resin component is also soft. Therefore, the component having such a coated metal plate cannot be used as a sliding member.

On the other hand, as a method of imparting abrasion resistance to a coating film on the surface of a zinc-plated metal sheet, a method of adding a large amount of a hard inorganic substance such as cerium oxide to the coating film as disclosed in Patent Document 2 is known. In particular, the cerium oxide system has an anti-rust effect in addition to hardness, and therefore is often used as an inorganic substance added to a coating film on the surface of a metal plate.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2007-269018

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2000-248379

However, when a large amount of inorganic substances are added to the coating film, the film forming property is deteriorated, so that the coating film easily passes through the water and the corrosion resistance is deteriorated. Further, in the case where the zinc plated metal plate is plated under high temperature and high humidity, there is a phenomenon called blackening, and if the inorganic substance is excessively added, the blackening resistance is also deteriorated. Therefore, when a hard inorganic substance such as cerium oxide is added to the coating film in a large amount, the coating film is hard, but the corrosion resistance or the blackening resistance tends to be deteriorated, and it is impossible to provide all of the abrasion resistance and corrosion resistance. Blackboard resistant to blackening. Therefore, it is necessary to use a material having a high cost such as alloy plating of stainless steel or zinc with other metals in order to make the wear resistance necessary.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a resin-coated zinc-plated metal sheet which is excellent in corrosion resistance, abrasion resistance, and blackening resistance.

A resin-coated zinc-plated metal sheet of the present invention which solves the above problems, characterized in that a first layer containing a small amount of colloidal cerium oxide is laminated on a surface of a zinc-plated metal sheet, and laminated on the first layer A second layer containing a thixotropic agent and a large amount of colloidal ceria. Specifically, it is a tree A zinc-coated zinc plated metal plate is laminated on at least one side of a metal plate coated with a zinc plating layer, and a first layer having a thickness of 0.2 μm or more is laminated, and a film thickness of 0.2 μm or more is laminated on the first layer. The second layer is characterized in that the first layer is 100% by mass of the total of the resin component and the colloidal cerium oxide, the resin component is 70 to 95% by mass, and the colloidal cerium oxide is 5 to 30% by mass. In the total of 100% by mass of the two-layer resin component, the colloidal cerium oxide, and the thixotropic agent, the resin component is 14 to 49.95 mass%, the colloidal cerium oxide is 50 to 80% by mass, and the thixotropic agent is 0.05 to 6% by mass. .

The total thickness of the first layer and the second layer is preferably 0.4 to 5 μm, and the total thickness of the first layer and the second layer is preferably 0.4 to 1.5 μm.

The resin composition forming the second layer preferably contains at least one of a polyolefin resin, a polyurethane resin, and a polyester resin.

At least one of a crosslinking agent and a decane coupling agent is preferably contained in at least one of the resin compositions for forming the first layer and the second layer.

According to the present invention, high-cost alloy plating or stainless steel is not used, and a resin layer excellent in corrosion resistance, abrasion resistance, and blackening resistance can be provided by laminating a specific resin layer by an inexpensive zinc-plated metal plate. Painted with zinc plated metal sheets.

[Fig. 1] Test material after abrasion resistance test, photographing of test material without slip marks.

[Fig. 2] The test material after the abrasion resistance test, and the photographing of the test material with significant sliding marks.

The resin-coated zinc-plated metal plate of the present invention (hereinafter, also referred to as "resin laminate" alone) is formed on at least one side of a metal plate covered with a zinc plating layer, and the first layer is laminated thereon. A second layer of resin coated zinc plated metal sheets is laminated on the first layer. The resin laminated board of the present invention laminates a first layer using a resin composition containing a small amount of colloidal cerium oxide, and a resin composition containing a thixotropic agent and a large amount of colloidal cerium oxide is used on the first layer. And the second layer of the layer. Hereinafter, the resin laminated board of this invention is demonstrated in detail.

〔Metal plate〕

The metal plate used in the present invention is not particularly limited as long as it is a zinc-plated metal plate. For example, a hot-rolled original plate electrogalvanized sheet metal (EG) to which electrogalvanized sheet is applied by hot-rolled metal sheet, and cold-rolled original sheet molten zinc plated metal sheet (GI) to which cold-rolled sheet is subjected to molten zinc plating may be used. Alloyed molten zinc plated metal plate (GA). Among these metal plates, an electrogalvanized metal plate (EG) is preferred. Electro-galvanized sheet metal (EG) for thin TVs After the machine, the cover and other electronic and electrical equipment are externally mounted.

The method for forming the electroplated zinc layer, the molten zinc plating layer or the alloyed molten zinc plating layer on the metal plate is not particularly limited, and a common method of electrogalvanizing treatment, molten zinc plating treatment, or the like may be employed. Alloying treatment using common methods. For example, in the case of producing an electrogalvanized metal plate, a method of performing electrogalvanization treatment by immersing a zinc solution immersed in 55 ° C at the same time may be mentioned. In the case of producing a molten zinc-plated metal plate, molten steel plating is applied to a plating bath adjusted to a temperature of about 430 to 500 ° C, followed by cooling. Moreover, in the case of producing a metallized molten zinc-plated metal plate, after the molten zinc plating, it is heated to a temperature of about 500 to 750 ° C, and then alloyed and cooled.

In addition, the amount of plating per one surface is not particularly limited, and for example, in the case of an electrogalvanized metal plate, it is about 10 to 100 g/m ² , and in the case of a molten zinc plated metal plate. Set to about 10~100g/m ² .

The above metal plate is formed into a bottom layer by performing substrate treatment on at least one side. For example, if the surface of the metal plate on the side where the first layer and the second layer are formed has the chemical conversion film layer (underlayer) formed by the substrate treatment, the adhesion between the metal plate and the first layer is improved.

Examples of the chemical conversion film layer (bottom layer) include an organic film layer, an inorganic film layer, a phosphate film layer, and a chromate film layer. Among these layers, an organic film layer, an inorganic film layer, and a phosphate film layer are preferable. As the organic film layer, for example, a polyolefin resin, an epoxy resin, a polyacryl resin, a polyurethane resin, or a polyester tree is suitably selected. A fat, a fluorine-based resin, a mixture of these components, a copolymer, a modified resin, or the like may be used. Further, in the organic film, a cerium oxide gel, a colloidal cerium oxide, or the like is added for the purpose of improving the corrosion resistance, and various wax components are added in a small amount for the purpose of improving the workability after the application of the coating film, or It is also possible to add a decane coupling agent for the purpose of improving the adhesion of the coating film. Examples of the inorganic film layer include a tellurite film layer, and phosphoric acid or a fluoride may be added to the tantalate film.

The amount of adhesion to the film layer (bottom layer) is not particularly limited. However, it is preferably an organic film layer or an inorganic film layer. From the viewpoint of corrosion resistance, the dry mass is preferably 10 mg/m ² or more. However, if it exceeds 50 mg/m ² , the improvement effect of corrosion resistance is saturated, and the manufacturing cost increases.

〔level one〕

The first layer is formed of a resin composition containing a resin component and colloidal cerium oxide (hereinafter referred to as a resin composition for forming a first layer).

<Resin component>

The resin component is not particularly limited, and a polyurethane resin, a polyolefin resin, a polyester resin, a polyacryl resin, a fluorine resin, a polyoxyn resin, and a mixture of these resins or The modified resin or the like is suitably used, and it may be used alone or in combination of two or more. Among them, at least one of a polyolefin resin, a polyurethane resin, and a polyester resin is preferable in that it can obtain excellent liquid stability. A polyolefin resin is preferable, and a polyethylene resin is more preferable.

In the total of 100% by mass of the first layer resin component and the colloidal cerium oxide, the resin component is preferably 70 to 95% by mass, and preferably 75 to 90% by mass. If it is outside the above range, there is a concern that corrosion resistance and blackening resistance are lowered.

(polyolefin resin)

The polyolefin-based resin to be used in the present invention is not particularly limited, but the polyolefin-based resin is preferably an olefin-α,β-unsaturated carboxylic acid copolymer (hereinafter referred to as "olefin-acid copolymer"). . The olefin-acid copolymer can improve corrosion resistance.

Further, the copolymer of the olefin-acid copolymer olefin and the α,β-unsaturated carboxylic acid of the present invention means that the constituent unit derived from the olefin is 50% by mass or more based on the copolymer (that is, The constituent unit derived from the α,β-unsaturated carboxylic acid is 50% by mass or less.

(olefin-α,β-unsaturated carboxylic acid copolymer)

The above olefin-acid copolymer can be produced by copolymerizing an olefin and an α,β-unsaturated carboxylic acid by a known method, and is also commercially available. The olefin-acid copolymer system may be used alone or in combination of two or more.

The olefin system which can be used for the production of the olefin-acid copolymer is not particularly limited, but ethylene, propylene or the like is preferred, and ethylene is preferred. The olefin-acid copolymer-based olefin constituent unit may be obtained from only one type of olefin, or may be obtained from two or more types of olefins.

The α,β-unsaturated carboxylic acid which can be used for the production of the olefin-acid copolymer is not particularly limited, and examples thereof include monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, and isocrotonic acid; Dicarboxylic acid such as acid, fumaric acid or itaconic acid. Among these components, acrylic acid is desirable. The constituent unit of the olefin-acid copolymer-based α,β-unsaturated carboxylic acid may be obtained from only one kind of α,β-unsaturated carboxylic acid, or may be obtained from two or more kinds of α,β-unsaturated carboxylic acids.

The α,β-unsaturated carboxylic acid unit in the olefin-acid copolymer realizes an effect of improving the adhesion to an adjacent resin layer or a metal plate, and effectively exhibits the α in the action copolymer. The unit amount of the β-unsaturated carboxylic acid is preferably 5% by mass or more, and more preferably 10% by mass or more. On the other hand, the upper limit of the unit amount of the α,β-unsaturated carboxylic acid in the copolymer is 50% by mass as described above, but from the viewpoint of corrosion resistance, it is preferably 30% by mass or less, and more preferably 25%. Below mass%.

The olefin-acid copolymer may have a constituent unit derived from another monomer in a range that does not adversely affect the secondary aggregation inhibition of the colloidal cerium oxide. In the olefin-acid copolymer, the constituent unit amount of the other monomer is preferably 10% by mass or less, more preferably 5% by mass or less, and the most desirable olefin-acid copolymer is only olefin and α, β. - A constituent of an unsaturated carboxylic acid. An ideal olefin-acid copolymer is an ethylene-acrylic acid copolymer.

The weight average molecular weight (Mw) of the olefin-acid copolymer is preferably from 1,000 to 100,000, more preferably from 3,000 to 70,000, still more preferably from 5,000 to 30,000, in terms of polystyrene. This Mw system can be Styrene was measured as a standard GPC.

(α,β-unsaturated carboxylic acid polymer)

Further, the polyolefin-based resin used in the present invention is preferably composed of an olefin-acid copolymer and an α,β-unsaturated carboxylic acid polymer (hereinafter referred to as "carboxylic acid polymer"). The olefin-acid copolymer and the carboxylic acid polymer can improve corrosion resistance.

In the "carboxylic acid polymer" of the present invention, a polymer obtained by polymerizing an α,β-unsaturated carboxylic acid as a monomer (also containing a copolymer) means that it is derived from α,β-unsaturated. The constituent unit of the carboxylic acid is 90% by mass or more in the polymer.

The carboxylic acid polymer may be a homopolymer or a copolymer of one or more kinds of α,β-unsaturated carboxylic acids or a copolymer obtained by further copolymerizing other monomers (other than olefins). Such a carboxylic acid polymer can be produced by a known method and additionally commercially available. One type or two or more types may be used for the carboxylic acid polymer.

An α,β-unsaturated carboxylic acid which can be used in the production of a carboxylic acid polymer can be used as the α,β-unsaturated carboxylic acid which can be exemplified for the synthesis of the above olefin-acid copolymer. Among these components, acrylic acid and maleic acid are desirable, and maleic acid is preferred.

The carboxylic acid polymer may contain a constituent unit derived from a monomer other than the α,β-unsaturated carboxylic acid, but the constituent unit amount of the other monomer is 10% by mass or less based on the polymer, and is preferably The carboxylic acid polymer composed of only α,β-unsaturated carboxylic acid is preferably 5 mass% or less.

Examples of the preferred carboxylic acid polymer include polyacrylic acid, polymethacrylic acid, acrylic acid-maleic acid copolymer, polymaleic acid, and the like. Among these components, in particular, adjacent resins are mentioned. From the standpoint of the adhesion of the layer or the metal plate, etc., polymaleic acid is preferred. Since the polymaleic acid has a large amount of carboxyl groups, the adhesion to an adjacent resin layer or a metal plate is further improved.

The weight average molecular weight (Mw) of the carboxylic acid polymer is preferably from 500 to 30,000 in terms of polystyrene, more preferably from 800 to 10,000, more preferably from 900 to 3,000, most preferably from 1,000 to 2,000. This Mw system can be determined by using polystyrene as a standard GPC.

The content ratio (mass ratio) of the olefin-acid copolymer and the carboxylic acid polymer in the polyolefin resin is preferably 1,000:1 to 10:1, more preferably 200:1 to 20:1, still more preferably 100: 1~25:1. When the content ratio of the carboxylic acid polymer is too low, the effect of combining the olefin-acid copolymer and the carboxylic acid polymer may not be sufficiently exhibited. On the other hand, if the content ratio of the carboxylic acid polymer is excessive, the composition is The medium olefin-acid copolymer is phase-separated from the carboxylic acid polymer, and there is a fear that the resin layer cannot be formed uniformly.

<colloidal cerium oxide>

The resin composition for forming a first layer contains colloidal cerium oxide. The colloidal cerium oxide (solid content) is contained in an amount of 5% by mass or more (more preferably 10% by mass or more) and 30% by mass or less (more preferably 20% by mass) based on 100% by mass of the total of the resin component and the colloidal cerium oxide. %the following). When the content of the colloidal cerium oxide is outside the above range, there is a resin laminated board Concerns about low corrosion resistance or blackening resistance. The reason why the corrosion resistance or the blackening resistance of the resin laminated sheet is improved is presumed to be due to the dissolution or dissolution of the colloidal cerium oxide in a corrosive environment, thereby causing a pH buffering action or a passive film forming action. Further, by containing the colloidal cerium oxide, it is possible to prevent the occurrence of the coating (the unattached portion) where the first layer does not exist during the coating of the resin composition for forming the first layer.

The colloidal cerium oxide is not particularly limited, but is preferably a colloidal cerium oxide having a particle diameter of 4 to 20 nm from the viewpoint of improving the dispersibility or corrosion resistance of the resin composition for forming a first layer. Specifically, a colloidal cerium oxide having a particle diameter of 4 to 6 nm ("SNOWTEX (registered trademark) XS" manufactured by Nissan Chemical Industries, Ltd.) and a colloidal particle having a particle diameter of 8 to 11 nm are commercially available.矽 矽 矽 SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN SN In particular, "SNOWTEX (registered trademark) XS" is ideal among these.

<crosslinker>

In order to crosslink the resin, a crosslinking agent may be added to the resin composition for forming the first layer. The corrosion resistance of the resin laminated board can be improved by including the crosslinking agent. In the 100% by mass of the total solid content of the crosslinking agent-based resin composition for forming a first layer, it is preferably 0.5 to 10% by mass, and preferably 1 to 5% by mass. Further, in the present specification, the so-called full solids system is called a resin component, a colloidal cerium oxide, a thixotropic agent, a decane coupling agent, and a crosslinking agent. The total of the forms.

The crosslinking agent is preferably an epoxy-based crosslinking agent from the viewpoint of reactivity, and examples thereof include sorbitol polyglycidyl ether, (poly)glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, and trimethylolpropane. A polyglycidyl ether such as polyglycidyl ether, neopentyl glycol diglycidyl ether or (poly)ethylene glycol diglycidyl ether or polyglycidylamine. As such an epoxy-based crosslinking agent, EPICLON (registered trademark) CR75 or CR5L manufactured by DIC Corporation can be obtained.

<decane coupling agent>

A decane coupling agent may also be added to the resin composition for forming the first layer. By containing a decane coupling agent, the corrosion resistance of the resin laminated board or the adhesion of the first layer to the metal sheet or the adhesion of the second layer to the first layer can be improved. As the decane coupling agent, a decane coupling agent having a glycidoxy group at the terminal is preferable, and examples thereof include γ-glycidoxypropyltrimethoxydecane and γ-glycidoxypropylmethyldiethoxy group. Decane, vinyl ginseng (β-methoxyethoxy) decane, and the like. In addition, a commercially available product may be used as the decane coupling agent, and examples thereof include "KBM 403" (manufactured by Shin-Etsu Chemical Co., Ltd., γ-glycidoxypropyltrimethoxydecane).

The content of the decane coupling agent is preferably from 1 to 10% by mass, and preferably from 2 to 5% by mass, based on 100% by mass of the total solid content of the resin composition for forming a first layer. When the content of the decane coupling agent is less than 1% by mass, the corrosion resistance of the resin laminated plate or the adhesion between the first layer and the metal plate or the adhesion between the second layer and the first layer may be lowered. The other side When the content of the decane coupling agent exceeds 10% by mass, the corrosion resistance of the resin laminated plate or the adhesion between the first layer and the metal plate or the adhesion between the second layer and the first layer is saturated. Propensity.

(film thickness of the first layer)

The first layer can be formed by applying a resin composition for forming a first layer to a specific dry film thickness on one or both sides of the above-mentioned metal plate, and drying it. The film thickness of the first layer is preferably 0.2 μm or more, preferably 0.3 μm or more, more preferably 0.4 μm or more, particularly preferably 0.6 μm or more, and most preferably 1 μm or more, and most preferably 4 μm or less, more preferably 4 μm or less. It is 3.5 μm or less, more preferably 3 μm or less, and most preferably 2 μm or less. If the film thickness is less than 0.2 μm, the corrosion resistance is lowered. When the film thickness exceeds 4 μm, the corrosion resistance, the abrasion resistance, and the blackening resistance are excellent, but it is difficult to obtain a more improved effect, and the time required for coating or drying becomes long, and the manufacturing cost is increased. .

〔Second floor〕

The second layer is formed of a resin composition containing a resin component, colloidal cerium oxide, and a thixotropic agent (hereinafter referred to as a resin composition for forming a second layer).

<Resin component>

The resin component is not particularly limited, and may be a polyurethane resin, a polyolefin resin, a polyester resin, a polyacryl resin, or a fluorine system. The resin, the polyoxymethylene resin, and the resin which is mixed or modified with these resins are used as appropriate, and they may be used singly or in combination of two or more. Among them, a polyolefin resin, a polyurethane resin, and a polyester resin are preferable from the viewpoint of obtaining excellent liquid stability.

The second layer is preferably 100% by mass of the resin component, the colloidal cerium oxide, and the thixotropic agent, and the resin component is 14 to 49.95 mass%, and preferably 20 to 35 mass%. If it is less than 14% by mass, there is a concern that corrosion resistance is low. On the other hand, when it exceeds 49.95% by mass, there is a concern that abrasion resistance is lowered.

(polyolefin resin)

The polyolefin resin used in the second layer is not particularly limited, but the polyolefin resin used in the second layer may be the same as the resin used in the first layer, but may be different. It is desirable that the resin used in the layer is the same. The suitable polyolefin-based resin is the same as the polyolefin-based resin added to the first layer-forming resin composition.

(polyurethane resin)

The polyurethane resin used in the second layer is not particularly limited, but a resin obtained by reacting a polyol with a polyisocyanate is preferred. In this case, the polyhydric alcohol and the polyisocyanate may be used alone or in combination of two or more kinds, and the polyurethane-based resin may be used alone or in combination of two or more.

As the aforementioned polyol, for example, there are two in the molecule. The upper hydroxyl group (hydroxyl group) is not particularly limited, and examples thereof include polyacrylic acid polyols, polyester polyols, and polyether polyols.

The polyacrylic acid polyol is, for example, a copolymer of a methacrylate monomer and a monomer having a hydroxyl group. Here, examples of the methacrylate single system include methyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and cyclohexyl (meth)acrylate. Wait. Examples of the single system having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and (meth)acrylic acid. a hydroxyalkyl (meth) acrylate such as 2-hydroxybutyl ester, 4-hydroxybutyl (meth)acrylate or 2-hydroxypentyl (meth)acrylate; a polyol such as glycerin or trimethylolpropane (meth)acrylic acid monoester; N-hydroxymethyl (meth) acrylamide and the like. Further, the polyacrylic acid polyol may be a monomer other than the (meth) acrylate monomer and the hydroxyl group-containing monomer, and may be copolymerized with another monomer. For example, (meth)acrylic acid or the like may be used. Unsaturated monocarboxylic acid; unsaturated dicarboxylic acid such as maleic acid and its anhydride and mono- or diester; unsaturated nitrile such as (meth)acrylonitrile; (meth) acrylamide, N - unsaturated decylamines such as hydroxymethyl (meth) acrylamide; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether; and α of ethylene, propylene, etc. An olefin; a halogenated α,β-unsaturated aliphatic monomer such as vinyl chloride or vinylidene chloride; or an α,β-unsaturated aromatic monomer such as styrene or α-methylstyrene.

The polyester polyol is, for example, a reaction of a polybasic acid component and a polyol component. As a polybasic acid component For example, phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, biphenyldicarboxylate can be used. An aromatic dicarboxylic acid such as acid or tetrahydrophthalic acid; oxalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, hydrazine Fats of dicarboxylic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, tartaric acid, alkyl succinic acid, linoleic acid, maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, etc. a dicarboxylic acid; an alicyclic dicarboxylic acid such as hexahydrophthalic acid, tetrahydrophthalic acid, 1,3-cyclohexanedicarboxylic acid or 1,4-cyclohexanedicarboxylic acid; or It is a reactive derivative of an acid anhydride, an alkyl ester or an acid halide of these components. As the polyol component, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 1 can be used. ,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1-methyl-1,3-butanediol, 2-methyl-1,3-butanediol, 1 -methyl-1,4-pentanediol, 2-methyl-1,4-pentanediol, 1,2-dimethyl-neopentyl glycol, 2,3-dimethyl-neopentyl glycol , 1-methyl-1,5-pentanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,2-dimethylbutanediol , 1,3-dimethylbutanediol, 2,3-dimethylbutanediol, 1,4-dimethylbutanediol, diethylene glycol, triethylene glycol, polyethylene glycol, two Propylene glycol, polypropylene glycol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol, bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F, and the like.

The polyether polyol is obtained, for example, by ring-opening polymerization of an alkylene oxide by a polyol. Examples of the polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, and trimethylolpropane. Examples of the alkylene oxide system include ethylene oxide and epoxy. Propane, butylene oxide, styrene oxide, tetrahydrofuran, and the like.

Examples of the polyisocyanate include tetramethylene diisocyanate, dodecamethylene diisocyanate, 1,4-butane diisocyanate, hexamethylene diisocyanate, and 2,2,4-trimethyl six. Methylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, isocyanate diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methylpentane-1 , an aliphatic diisocyanate such as 5-diisocyanate; isophorone diisocyanate, hydrogenated benzene dimethylene diisocyanate, 4,4'-cyclohexanemethane diisocyanate, 1,4-cyclohexane diisocyanate, methyl An alicyclic diisocyanate such as cyclohexyl diisocyanate or 1,3-bis(isocyanatomethyl)cyclohexane; toluene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4' -diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, 1,5- Aromatic diisocyanate such as naphthyl diisocyanate, benzene dimethylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate An acid ester; an aromatic aliphatic diisocyanate such as dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate or α,α,α,α-tetramethylbenzenedimethylene diisocyanate or the like.

Further, the above-mentioned polyurethane resin-based polyol and polyisocyanate may be further reacted with other polyols or chain extenders. Examples of other polyhydric alcohols include sorbitol, 1,2,3,6-hexanetetraol, 1,4-sorbitol anhydride, 1,2,4-butanetriol, 1,2,5. a polyhydric alcohol having 3 or more hydroxyl groups, such as pentane triol, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol or the like. As a chain extender, for example Examples thereof include a dihydroxyalkyl alkane acid (for example, dimethylol acetate, dimethylolbutanoic acid, dimethylolpropionic acid, dimethylolbutyric acid, dimethylolvaleric acid, etc.) Hydroxydicarboxylic acid; dihydroxysuccinic acid; ethylene glycol, diethylene glycol, triethylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol a glycol such as pentanediol, 1,6-hexanediol or propylene glycol; an aliphatic diamine such as ethylenediamine, propylenediamine, hexamethylenediamine, 1,4-butanediamine or amineethylethanolamine An alicyclic diamine such as isophorone diamine or 4,4'-dicyclohexylmethanediamine; an aromatic diamine such as benzenedimethylene diamine or tolyldiamine.

The reaction in the case of obtaining a polyurethane resin may be a generally known method. For example, a one-stage method in which one component is once reacted in a single reaction may be employed. In addition, the ratio of use of each component in the case of obtaining a polyurethane resin may be appropriately set. The molecular weight of the polyurethane resin is not particularly limited, but is preferably, for example, 5,000 to 600,000 in terms of number average molecular weight, and preferably 10,000 to 400,000.

The polyurethane resin is preferably used as an aqueous dispersion. If this is done, the risk of explosion due to the use of organic solvents or the load on the environment and the human body can be avoided. An aqueous dispersion of a polyurethane resin is typically an emulsion of particles of a polyurethane resin. As the aqueous solvent to be used as the dispersion medium, water or water and a hydrophilic organic solvent (for example, an alcohol solvent such as methanol, ethanol, isopropyl alcohol, ethylene glycol or propylene glycol; ethyl acetate or butyl acetate) can be used. , an ester solvent such as γ-butyrolactone; a ketone solvent such as acetone; tetrahydrofuran, A mixed solvent of an ether solvent such as an alkylene oxide or an aprotic polar solvent such as N-methylpyrrolidone, in particular, water is preferred. In the case of using a mixed solvent of water and a hydrophilic organic solvent, the content ratio of the hydrophilic organic solvent is preferably 50% by mass or less based on the mixed solvent, more preferably 30% by mass or less, and still more preferably 10% by mass or less.

When the polyurethane resin is used as an aqueous dispersion, the stability of the polyurethane-based resin in the aqueous dispersion medium may be improved, and the dispersion may be neutralized. Agent. Examples of the neutralizing agent include ammonia, N-methylmorpholine, triethylamine, dimethylethanolamine, methyldiethanolamine, triethanolamine, morpholine, tripropylamine, ethanolamine, and triisopropanol. Amine, 2-amino-2-methyl-1-propanol, and the like.

For the aqueous dispersion of the polyurethane resin, a commercially available product may be used, and for example, a TAKERAKKU (registered trademark) series (WS-4000, etc.) manufactured by Mitsui Chemicals Polyurethane Co., Ltd., and ADEKA Corporation may be used. The ADEKA BONTIGHTER (registered trademark) series (HUX-550, HUX-541, HUX-522, etc.) and the SUPERFLEX (registered trademark) series (SF170, etc.) manufactured by Daiichi Kogyo Co., Ltd., the above-mentioned water dispersion system can be used alone. Two or more types can also be used in combination.

(Polyester resin)

The polyester resin to be used in the second layer is not particularly limited, but is preferably an aqueous dispersion in which a polyester resin is dispersed in an aqueous medium (hereinafter referred to as a water-dispersible polyester resin). An aqueous dispersion in which a water-dispersible polyester resin-based polyester resin is dispersed in an aqueous medium to form a polycondensation of a water-dispersible polyester resin The ester resin is obtained by polycondensing a polyvalent carboxylic acid and ethylene glycol.

As the polyvalent carboxylic acid component constituting the polyester resin, an aromatic, aliphatic, or alicyclic dicarboxylic acid or a trivalent or higher polyvalent carboxylic acid or an ester derivative of these components can be used.

As the aromatic dicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, 2,5-dimethylterephthalic acid, 1,4-naphthalene dicarboxylic acid, or biphenyl dicarboxylic acid can be used. An ester-forming derivative of these components, 2,6-naphthalenedicarboxylic acid, 1,2-bisphenoxyethane-p,p'-dicarboxylic acid, benzoindandicarboxylic acid, and the like.

Further, as the aliphatic and alicyclic dicarboxylic acid, succinic acid, adipic acid, sebacic acid, sebacic acid, dodecanedioic acid, dimer acid, and 1,3-cyclopentane dicarboxylic acid can be used. An acid, 1,2-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, or the like, and an ester-forming derivative of the component.

As the diol component constituting the polyester resin, ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, 1,3-propanediol, 1,3-butylene glycol, or 1,4-ethyl alcohol can be used. Butylene glycol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-anthracene Alcohol, 2,4-dimethyl-2-ethylhexane-1,3-diol, neopentyl glycol, 2-ethyl-2-butyl-1,3-propanediol, 2-ethyl- 2-isobutyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,2,4-trimethyl-1,6-hexanediol, 1,2-cyclohexane Dimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, 4,4'-di Phenyl sulfide, bisphenol A, 4,4'-methylene glycol, 4,4'-(2-norbornadiene) diphenol, 4,4'-dihydroxybiphenyl, o-, m- and P-dihydroxybiphenyl, 4,4'-isopropylidene phenol, 4,4'-isopropylidene glycol, Cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, and the like.

In addition, in order to facilitate water dispersion of the polyester resin, a compound containing a carboxylic acid (salt) group, a compound containing a sulfonic acid (salt) group, a compound containing a phosphonic acid (salt) group, or the like may be copolymerized.

Further, in the present invention, as the polyester-based resin, for example, a modified polyester copolymer such as a modified block copolymer such as acrylic acid, urethane or epoxy group, or a graft copolymer may be used. Things.

The polyester resin which is preferably used as the acid component may be, for example, terephthalic acid, isophthalic acid, sebacic acid or 5-sodium sulfoisophthalic acid, and the diol component may be used. A copolymer selected from ethylene glycol, diethylene glycol, 1,4-butanediol, and neopentyl glycol.

The above polyester resin can be produced by the following production method. For example, if the dicarboxylic acid component is composed of terephthalic acid, isophthalic acid, or 5-sodium sulfoisophthalic acid, the diol component is a polymer composed of ethylene glycol or neopentyl glycol. The ester-based resin can be produced by directly esterifying the monomers of these components, or by the second stage of the transesterification reaction and the second stage of the polycondensation reaction of the reaction product of the first stage. The method is manufactured by the same. In this case, as the reaction catalyst, for example, an alkali metal, an alkaline earth metal, manganese, cobalt, zinc, ruthenium, osmium, or a titanium compound can be used.

The number average molecular weight (Mn) of the polyester resin is preferably 10,000 to 20,000, more preferably 15,000 to 20,000, in terms of polystyrene.

Further, the glass transition temperature (Tg) of the polyester resin is preferably 40 to 70 ° C, more preferably 40 to 67 ° C.

For the water-dispersible polyester resin, a commercially available product may be used. For example, "VYLONAL (registered trademark) MD-1100", "VYLONAL (registered trademark) MD-1200", and "VYLONAL (registered trademark) MD, manufactured by Toyobo Co., Ltd., may be used. -1245", etc., the above resin may be used singly or in combination of two or more.

<colloidal cerium oxide>

The second layer contains colloidal cerium oxide. In the second layer, the colloidal cerium oxide is contained in an amount of 50% by mass or more (more preferably 60% by mass or more) or 80% by mass or less based on 100% by mass of the total of the resin component, the colloidal cerium oxide, and the thixotropic agent. It is desirably 75 mass% or less). If the content of the colloidal cerium oxide is less than 50% by mass, there is a concern that the wear resistance is low. On the other hand, if the content of the colloidal cerium oxide exceeds 80% by mass, there is a concern that the corrosion resistance is lowered. In addition, when the colloidal cerium oxide is contained, it is possible to prevent the occurrence of the coating (the unattached portion) where the second layer does not exist during the coating of the resin composition for forming the second layer.

The colloidal cerium oxide is not particularly limited, but is preferably a colloidal cerium oxide having a particle diameter of 4 to 20 nm from the viewpoint of improving the dispersibility or corrosion resistance of the resin composition for forming a second layer. Specifically, a colloidal cerium oxide having a particle diameter of 4 to 6 nm ("SNOWTEX (registered trademark) XS" manufactured by Nissan Chemical Industries, Ltd.) and a colloidal particle having a particle diameter of 8 to 11 nm are commercially available. Cerium oxide ("SNOWTEX (registered trademark) S" manufactured by Nissan Chemical Industries Co., Ltd.) and colloidal cerium oxide having a particle size of 10 to 20 nm (commercially produced by Nissan Chemical Co., Ltd.) Among them, "SNOWTEX (registered trademark) 40"), etc., is particularly desirable for "SNOWTEX (registered trademark) XS".

<Tactile agent>

The second layer contains a thixotropic agent. The thixotropic agent may be, for example, a filler of bentonite, calcium carbonate, kaolin, clay or the like, a polymerized linseed oil, a castor oil wax, a polyolefin, a ceria gel, an aluminum organic acid salt, a cellulose, a guanamine wax, A polyamine-based thixotropic agent or the like described later.

A thixotropic agent is preferably a polyamine-based thixotropic agent (polyamine amine salt). The polyamine-based thixotropic agent is obtained by reacting a dicarboxylic acid with a diamine, but is not particularly limited as long as it is a thixotropic agent which can be dispersed in the resin composition for forming a second layer. The polyamine-based thixotropic agent is obtained, for example, as a DISPARLON (registered trademark) AQ series, and can be obtained from a company such as Nanben Chemical Co., Ltd. In the AQ series, polyamine which is represented by the following chemical formula (R, R' is an alkyl group) is used as a main component, and the molecular weight of the polyamine in the AQ series is 3,000 or less.

Polyamide-based thixotropic agents can be thought of as forming a 3-dimensional mesh structure in the coating, allowing the thixotropic agents to interact with each other or with the resin or glue in the coating. The cerium dioxide is sterically hindered, or the steric hindrance between the particles is increased by adsorption, and the fluidity suppressing effect of the resin composition is exhibited. This mesh structure is composed of a van der Waals force or a hydrogen bond-like weak bond which is easily broken by a certain degree of shear stress, and the mesh structure is cut due to shear stress but if it is left standing Then the mesh structure is restored again. Therefore, by adding a thixotropic agent to the resin composition, thixotropy (shakenness) appears, and in the high shear rate region, the mesh structure is cut and the viscosity is lowered, and if it is left to stand, it becomes a low shear rate region. The structure is restored and the viscosity becomes high.

The thixotropic agent is preferably 0.05% by mass or more and 6% by mass or less, and 0.1% by mass or more and 2% by mass or less, based on 100% by mass of the total of the resin component, the colloidal cerium oxide, and the thixotropic agent. If it is less than 0.05% by mass, since the viscosity of the low shear rate region of the resin composition for forming a second layer is not sufficiently high, it becomes difficult to maintain a uniform wet film after coating until it remains after drying. In a uniform state, the wet film may flow, and there is a concern that a portion (unattached portion) where the second layer does not exist on the surface of the resin laminated plate occurs. On the other hand, when it exceeds 6% by mass, the effect of improving the appearance tends to be saturated.

<crosslinker>

In order to crosslink the resin, a crosslinking agent may be added to the resin composition for forming the second layer. The corrosion resistance of the resin laminated board can be improved by including the crosslinking agent. A suitable content of the crosslinking agent or a suitable crosslinking agent is the same as the crosslinking agent to which the resin composition for forming the first layer is added.

<decane coupling agent>

A decane coupling agent may also be added to the resin composition for forming the second layer. By containing a decane coupling agent, the corrosion resistance of the resin laminated board and the adhesion between the second layer and the first layer can be improved. A suitable amount of the decane coupling agent or a suitable decane coupling agent is the same as the decane coupling agent to which the resin composition for forming the first layer is added.

(film thickness of the second layer)

The second layer can be formed by applying a resin composition for forming the second layer to a specific dry film thickness on the first layer and drying it. The thickness of the second layer is preferably 0.2 μm or more, preferably 0.4 μm or more, more preferably 0.6 μm or more, more preferably 1 μm or more, and most preferably 4 μm or less, more preferably 3.5 μm or less, and more preferably 3 μm or less, and most preferably 2 μm or less. If the film thickness is less than 0.2 μm, there is a concern that abrasion resistance is lowered. On the other hand, when the film thickness exceeds 4 μm, the corrosion resistance, the abrasion resistance, and the blackening resistance are excellent, but it is difficult to obtain a more improved effect, and the time required for coating or drying becomes long. Will increase manufacturing costs.

[first layer and second layer]

The total thickness of the first layer and the second layer is 0.4 μm or more, more preferably 0.7 μm or more, more preferably 1 μm or more, and most preferably 5 μm or less, more preferably 4 μm or less, and still more preferably 3 μm or less. . When the total film thickness exceeds 5 μm, corrosion resistance, abrasion resistance, and blackening resistance are obtained. It is excellent, but it becomes difficult to obtain a more improved effect, and it takes a long time to apply or dry, and it becomes a manufacturing cost. Further, when the total film thickness is too large, the conductivity required for use in, for example, a home appliance field such as a thin television cannot be achieved.

It is preferable that the total thickness of the first layer and the second layer of the shell which requires high conductivity is 1.5 μm or less.

At least one of the resin composition for forming the first layer and the resin composition for forming the second layer contains at least one of a crosslinking agent and a decane coupling agent.

The benefit of the priority is claimed based on Japanese Patent Application No. 2015-056680, filed on March 19, 2015, and Japanese Patent Application No. 2015-247219, filed on Dec. The entire contents of the specification of Japanese Patent Application No. 2015-056680 and Japanese Patent Application No. 2015-247219 are incorporated herein by reference.

[Examples]

Hereinafter, the present invention will be described in detail based on examples. However, the following examples are not intended to limit the inventors of the present invention, and the modifications carried out within the scope of the present invention are not included in the scope of the present invention.

Hereinafter, "%" means "% by mass", and "part" means "parts by mass".

First of all, regarding the evaluation method used in the examples, The following instructions.

(1) Corrosion resistance

The test material (resin-coated zinc-plated metal plate) was subjected to a salt spray test of JIS Z 2371 for 240 hours. Thereafter, the occurrence of white rust on the surface of the test material was observed and evaluated on the basis of the following criteria.

○: The incidence of white rust is 20% or less

×: The incidence of white rust exceeds 20%

(2) Wear resistance

The Taber type abrasion tester manufactured by Yasuda Seiki Co., Ltd. was used. Specifically, the offset paper was wound around a copying paper (COPY & LASER PAPER manufactured by APRIL Fine Paper Co., Ltd.), and the load (self-weight) was set to 250 gf, and the wear roller was rotated by rotating the test material to perform an abrasion resistance test. The rotation speed of the wear wheel was set to 60 rpm, and the number of rotations of the wear wheel was set to 500 times. Thereafter, visual judgment was made on the basis of the following criteria.

○: There is a slight sliding mark or no sliding mark on the appearance of the test material (Fig. 1)

×: Significant sliding marks on the appearance of the test material (Fig. 2)

(3) Resistance to blackening

First, the L value of the test material was measured using a color difference meter (SZS-Σ90, manufactured by Nippon Denshoku Industries Co., Ltd.). Then, the test material was stored at 50 ° C and a humidity of 98% for 168 hours, and then the L value of the test material was measured again. will The difference ΔL between the L values before and after 168 hours of storage was calculated and quantitatively evaluated.

○: ΔL is 1.5 or less

×: ΔL is higher than 1.5

(4) Appearance evaluation (evaluation of unattached parts of wet film)

The second layer was a clear coating film containing no coloring pigment, and since the unattached portion after drying was not visually judged, it was evaluated as a wet film after coating. In the test material, after the second layer was applied, the coated surface of the edge portion of the test material of the A4 size was removed, and the appearance of the unattached portion was evaluated by the following criteria.

○: The unattached part occurred in full

×: The unattached portion did not occur

(5) Conductivity

Using a tester, the terminal was slid on the surface of the test material, and the resistance value was measured and evaluated on the basis of the following criteria.

◎: less than 500Ω

○: less than 500 Ω and less than 2000 Ω

△: 2000 Ω or more

(electrogalvanized metal plate)

As the metal plate, a metal plate to which zinc plating is used is specifically an electrogalvanized metal plate (EG) having a plate thickness of 0.8 mm and a zinc plating adhesion amount of 20 g/m ² on each of both surfaces of the metal plate.

(Method for producing polyolefin resin aqueous liquid)

In an autoclave equipped with an emulsifier equipped with a stirrer, a thermometer, and a temperature controller, an ethylene-acrylic acid copolymer ("PRIMACOR (registered trademark) 5990 I" manufactured by The Dow Chemical Co., Ltd., a constituent unit derived from acrylic acid: 20%, mass average was added. Mw (Mw): 20,000, melt index: 1300, acid value: 150) 200.0 parts, polymaleic acid aqueous solution (Nonpol (registered trademark) PMA-50 W, manufactured by Nippon Oil Co., Ltd.), Mw: about 1100 (poly) Styrene conversion, 50%) 8.0 parts, triethylamine 35.5 parts (0.63 equivalents relative to the carboxyl group of the ethylene-acrylic acid copolymer), and 6.9 parts of 48% NaOH aqueous solution (relative to the carboxyl group of the ethylene-acrylic acid copolymer) 1.5 parts by weight), 3.5 parts of tall oil fatty acid (HARTALL FA3 manufactured by HARIMA Chemical Co., Ltd.), and 792.6 parts of ion-exchanged water were sealed, and the mixture was rapidly stirred at 150 ° C and 5 atm for 3 hours, and then cooled to 30 ° C. Then, added a glycidyl coupling agent containing a glycidyloxy group ("TSL 8350" and γ-glycidoxypropyltrimethoxydecane) manufactured by Momentive Performance Material Co., Ltd. (formerly known as GE Toshiba Silicones), 10.4 parts, containing carbon dioxide Amino compound Spinning Chemical Co., Ltd. "CARBODILITE (registered trademark) SV-02), polycarbodiimide, Mw: 2,700, 40% solids) 31.2 parts, 72.8 parts of ion-exchanged water, stirred for 10 minutes to prepare an olefin-acid copolymer And an emulsion of an carboxylic acid polymer (emulsion concentration: about 20%, measured in accordance with JIS K 6833) to obtain an aqueous dispersion of a dispersed polyolefin resin (hereinafter referred to as a polyolefin resin) liquid).

(About No.1~40) [Formation method of the first layer]

To the aqueous solution of the polyolefin-based resin obtained above, colloidal cerium oxide (SNOWTEX (registered trademark) XS, manufactured by Nissan Chemical Industries, Ltd., 20% solid content) was added to prepare a resin composition for forming a first layer. The blending ratio of each component is adjusted so that the solid content is 40 to 100 parts of the polyolefin resin and the colloidal cerium oxide is 0 to 60 parts. The resin composition for forming the first layer was diluted with ion-exchanged water to a solid concentration of 10%, stirred at 700 rpm for 10 minutes in a dispersing mixer, and then a bar coater was used to form a film thickness of 0.08 on the surface of the EG original plate. The coating was applied in a manner of 2.59 μm, and dried at a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C × 12 seconds) to form a first layer on the EG original plate.

[Formation method of the second layer]

In the aqueous solution of the polyolefin-based resin obtained above, the above-mentioned colloidal cerium oxide and polyamine-based thixotropic agent (DISPARLON (registered trademark) AQ-607, manufactured by Kuamoto Kasei Co., Ltd., solid content 15%) were added to prepare a second layer. A resin composition is used. The blending ratio of each component was adjusted so that the solid content was 4.8 to 99.8 parts of the polyolefin resin, 0 to 95 parts of the colloidal cerium oxide, and 0.2 parts of the polyamine catalyzed thixotropic agent. The resin composition for forming the second layer was diluted with ion-exchanged water to a solid concentration of 10%, and stirred at 700 rpm for 10 minutes in a dispersing mixer, and then a bar coater was used on the first layer. The film was applied so as to have a film thickness of 0.05 to 2.02 μm, and dried at a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C × 12 seconds) to form a second layer on the first layer.

(About No.41) [Formation method of the first layer]

The above-mentioned colloidal cerium oxide was added to the aqueous polyolefin resin liquid obtained above to prepare a resin composition for forming a first layer. The blending ratio of each component was adjusted so as to be 85 parts of a polyolefin resin and 15 parts of a colloidal cerium oxide in terms of solid content. The resin composition for forming the first layer was diluted with ion-exchanged water to a solid concentration of 10%, stirred at 700 rpm for 10 minutes in a dispersing mixer, and then applied to a surface of the EG original plate by a bar coater to have a film thickness of 0.46 μm. The coating was carried out by heating and drying at a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C × 12 seconds) to form a first layer on the EG original plate.

[Formation method of the second layer]

Polyurethane-based resin aqueous solution (ADEKA BONTIGHTER (registered trademark) HUX-522, 30% solid content), and the above-mentioned colloidal cerium oxide and polyamine-based thixotropic agent were added to form a second layer. A resin composition is used. The blending ratio of each component was adjusted so that the solid content was 29.8 parts of a polyurethane resin, 70 parts of colloidal cerium oxide, and 0.2 part of a polyamine-based thixotropic agent. The resin composition for forming a second layer was diluted with ion-exchanged water to a solid concentration of 10%, stirred at 700 rpm for 10 minutes in a dispersing mixer, and then a bar coater was used to form a film thickness of 0.47 on the first layer. The film was applied in a μm manner, and dried at a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C × 12 seconds) to form a second layer on the first layer.

(About No.42) [Formation method of the first layer]

The first layer was formed on the zinc plated metal plate in the same manner as in No. 41.

[Formation method of the second layer]

The polyester-based resin aqueous solution (VYLONAL (registered trademark) MD-1200, manufactured by Toyobo Co., Ltd., 34% solid content) was added to the above-mentioned colloidal cerium oxide and a polyamine-based thixotropic agent to prepare a resin composition for forming a second layer. The blending ratio of each component was adjusted so that the solid content was 29.8 parts of a polyester resin, 70 parts of colloidal cerium oxide, and 0.2 part of a polyamine-based thixotropic agent. The resin composition for forming a second layer was diluted with ion-exchanged water to a solid concentration of 10%, stirred at 700 rpm for 10 minutes in a dispersing mixer, and then a bar coater was used to form a film thickness of 0.47 on the first layer. The film was applied in a μm manner, and dried at a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C × 12 seconds) to form a second layer on the first layer.

(About No.43~49) [Formation method of the first layer]

The above-mentioned colloidal cerium oxide, an epoxy-based crosslinking agent (EPICLON (registered trademark) CR75, manufactured by DIC Corporation), and a decane coupling agent (KBM403 manufactured by Shin-Etsu Chemical Co., Ltd.) were added in this order. The solid content was 100%), and a resin composition for forming a first layer was produced. The blending ratio of each component is adjusted so that the solid content is 79 to 85 parts of the polyolefin resin, 15 parts of the colloidal cerium oxide, 0 to 3 parts of the epoxy crosslinking agent, and 0 to 3 parts of the decane coupling agent. The resin composition for forming the first layer was diluted with ion-exchanged water to a solid concentration of 10%, stirred at 700 rpm for 10 minutes in a dispersing mixer, and then applied to a surface of the EG original plate by a bar coater to have a film thickness of 0.36. The coating was applied in a manner of 0.46 μm, and dried at a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C × 12 seconds) to form a first layer on the EG original plate.

[Formation method of the second layer]

The colloidal ceria, the epoxy-based crosslinking agent, the decane coupling agent, and the polyamine-based thixotropic agent are sequentially added to the aqueous polyolefin resin solution obtained as described above to prepare a second layer-forming resin. Things. The blending ratio of each component is 23.8 to 29.8 parts of polyolefin resin, 70 parts of colloidal cerium oxide, 0 to 3 parts of epoxy crosslinking agent, 0 to 3 parts of decane coupling agent, and polyamine series. The 0.2 part of the thixotropic agent was formulated. The resin composition for forming the second layer is diluted with ion-exchanged water to be solid. After the concentration was 10%, the mixture was stirred at 700 rpm for 10 minutes in a dispersing mixer, and then applied to the first layer by a bar coater at a film thickness of 0.36 to 0.47 μm to a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C). ×12 seconds) Heat drying to form a second layer on the first layer.

(About No. 50) [Formation method of the first layer]

The above-mentioned colloidal cerium oxide was added to the aqueous polyolefin resin liquid obtained above to prepare a resin composition for forming a first layer. The blending ratio of each component was adjusted so as to be 85 parts of a polyolefin resin and 15 parts of a colloidal cerium oxide in terms of solid content. The resin composition for forming the first layer was diluted with ion-exchanged water to a solid concentration of 10%, stirred at 700 rpm for 10 minutes in a dispersing mixer, and then applied to a surface of the EG original plate by a bar coater to have a film thickness of 0.30 μm. The coating was carried out by heating and drying at a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C × 12 seconds) to form a first layer on the EG original plate.

[Formation method of the second layer]

The above-mentioned colloidal ceria was added to the aqueous polyolefin resin liquid obtained above to prepare a resin composition for forming a second layer. The blending ratio of each component was adjusted so that the solid content was converted into 30 parts of a polyolefin resin and 70 parts of colloidal cerium oxide. The resin composition for forming a second layer was diluted with ion-exchanged water to a solid concentration of 10%, stirred at 700 rpm for 10 minutes in a dispersing mixer, and then a bar coater was used to form a film thickness of 0.45 on the first layer. The coating was applied in a μm manner, and dried at a plate temperature of 90 to 100 ° C (furnace temperature of 220 ° C × 12 seconds) to form a second layer on the metal plate.

[Industrial Applicability]

The resin-coated zinc-plated metal plate of the present invention is formed by laminating a first layer by using a resin composition containing a small amount of colloidal ceria, and a thixotropic agent and a large amount of colloid are used on the first layer. A resin-coated zinc-plated metal sheet excellent in corrosion resistance, abrasion resistance, and blackening resistance can be formed by laminating the second layer of the resin composition of cerium oxide. Therefore, the resin-coated zinc-plated metal sheet of the present invention can be used for housings for home electronic products, interior materials, exterior materials, steel furniture, and the like.

Claims (5)

A resin-coated zinc-plated metal plate which is laminated on at least one side of a metal plate coated with a zinc plating layer, laminated with a first layer containing a resin component and colloidal ceria, and laminated on the first layer A resin-coated zinc-plated metal plate of a second layer of a resin component, a colloidal cerium oxide, and a thixotropic agent, wherein the first layer film thickness is 0.2 μm or more, and the total of the resin component and the colloidal cerium oxide 100% by mass, the resin component is 70 to 95% by mass, the colloidal cerium oxide is 5 to 30% by mass, the second layer film thickness is 0.2 μm or more, and the total of the resin component, the colloidal cerium oxide, and the thixotropic agent In 100% by mass, the resin component is 14 to 49.95 mass%, the colloidal cerium oxide is 50 to 80% by mass, and the thixotropic agent is 0.05 to 6% by mass. The resin-coated zinc-plated metal plate according to claim 1, wherein the total thickness of the first layer and the second layer is 0.4 to 5 μm. The resin-coated zinc-plated metal plate according to claim 1, wherein the total thickness of the first layer and the second layer is 0.4 to 1.5 μm. The resin-coated zinc-plated metal sheet according to any one of claims 1 to 3, wherein the second layer contains at least one of a polyolefin resin, a polyurethane resin, and a polyester resin. The resin-coated zinc-plated metal sheet according to any one of claims 1 to 3, wherein at least one of the resin composition for forming the first layer and the second layer contains a crosslinking agent and a cyanide couple At least one of the mixture.