JPH08207199A - Resin coated metal panel and production thereof - Google Patents

Abstract

PURPOSE: To enhance abrasion resistance, lubricating properties or the like by forming a resin film on a metal panel from a compsn. prepared by adding silica particles, spherical polyethylene wax particles and an org. compd. having an aziridinyl group to an emulsion of a polyolefinic copolymer resin intermolecularly associated by ion clusters. CONSTITUTION: A resin film based on an emulsion of a polyolefinic copolymer resin intermolecularly associated by ion clusters and containing 5-30wt.% of silica particles, 0.5-20wt.% of spherical polyethylene wax particles and 1-20wt.% of an org. compd. having an aziridinyl group in terms of a solid is formed on the surface of a metal panel in an adhesion amt. of 0.2-2.5g/m<2> on a dry wt. basis. Silica particles impart excellent corrosion resistance and painting properties and further enhance the hardness of the resin film. Spherical polyethylene wax particles enhance lubricity, abrasion resistance, scratch resistance, deep drawing properties or mold abrasion resistance.

Description

Detailed Description of the Invention

[0001]

The present invention relates to abrasion resistance, workability, blackening resistance during processing, punching resistance, corrosion resistance and paintability which can be suitably used for applications such as household electric appliances and building materials. The present invention relates to an excellent resin-coated metal sheet, particularly a resin-coated steel sheet, and a method for producing such a resin-coated metal sheet, particularly a resin-coated steel sheet.

[0002]

2. Description of the Related Art Conventionally, aluminum sheets, stainless steel sheets, and surface-treated steel sheets such as electrogalvanized steel sheets and hot-dip galvanized steel sheets have been widely used as metal sheets used for household electric appliances and building materials. . Among the,
Conventionally, zinc-plated surface-treated steel sheets have been subjected to chromate treatment and phosphate treatment, and are widely used for various members such as home appliances, audio equipment, computer parts, and bottom plates of microwave ovens. ing. But,
In recent years, user needs for these surface-treated steel sheets have become more and more sophisticated, and various coating performances have been required.

For example, when the surface-treated steel sheet is used naked, it is required to have corrosion resistance, earthing property, fingerprint resistance that is inconspicuous even if fingerprints are attached, chemical resistance to alkalis and solvents, stain resistance, etc. To be done. In the case of press working or punching, lubricity, scratch resistance, deep drawing workability, die wear resistance, punching performance, blackening resistance of working sliding surface, press oil, quick drying Oil resistance of oil etc. is required.

Further, when the surface-treated steel sheet is shipped as a product in the form of a coil or sheet material from a steel sheet manufacturer, it is usually transported by a truck or the like. Rubbing also occurs, and in the case of a sheet material, overlapping steel plates may rub each other in the package, or scratches may occur on the surface of the steel plate. This scratch is a defect in which the part appears to be discolored black, and such a defect is called abrasion, which significantly deteriorates the commercial value of the surface-treated steel sheet and is difficult for users to use as a product. Happens.

[0005] Conventional inorganic surface-treated steel sheets such as chromate treatment and phosphate treatment cannot meet such various needs. Therefore, in recent years, many resin-coated steel sheets having the following organic resin coatings have been proposed. For example, first, in Japanese Patent Laid-Open No. 62-50480, after galvanizing a galvanized steel sheet, an organic coating film comprising a carboxylated polyolefin resin and an epoxy resin and containing colloidal silica is formed thereon. Accordingly, a galvanized steel sheet having improved corrosion resistance, paintability, solvent resistance, alkali resistance and fingerprint resistance is described. Similarly, secondly, JP-A-64-7308.
No. 3, gazette discloses ethylene-α, β- containing colloidal sols.
The polymerizable ethylenically unsaturated compound was added to the dispersion liquid of the unsaturated carboxylic acid copolymer resin, emulsion polymerization was performed, and after the completion of the polymerization, a treatment liquid in which the polymer was further crosslinked was prepared, and this was chromated. Applying to galvanized steel sheet, adhesion,
A surface-treated steel sheet having improved fingerprint resistance, coin scratch resistance, corrosion resistance, etc. is described.

Thirdly, in Japanese Patent Publication No. 5-54823, after galvanizing a galvanized steel sheet, a resin comprising an ethylene-ethylenically unsaturated carboxylic acid copolymer resin containing colloidal silica and an organic substance having an aziridinyl group is disclosed. It is described that a resin-coated steel sheet having improved paintability, corrosion resistance, chemical resistance, and scratch resistance can be obtained by applying a liquid and drying it to form a crosslinked coating.

Fourth, in JP-A-6-246229, a galvanized steel sheet is subjected to chromate treatment, on which ethylene and α, β-ethylenically unsaturated carboxylic acid are contained as main components, and It is described that an organic composite-coated steel sheet having improved blackening resistance is obtained by maintaining a good corrosion resistance by forming a resin coating made of an ethylene-based ionomer resin in which 60 to 80% of the groups are neutralized with sodium ions. Has been done.

[0008] Fifth, in Japanese Patent Publication No. 5-13829, a resin coating mainly containing an acrylated epoxy resin and containing fluorine particles and silica particles is formed on a galvanized steel sheet, which is easy to press-form. It is described that a resin-coated steel sheet is obtained.

The above-mentioned first to third prior arts are
Some improvement has been achieved in the performance required for naked use by users, such as paintability and fingerprint resistance. In addition, a certain degree of effect is recognized in terms of scratch resistance due to handling by the user. However, since the coating film of these resin-coated steel sheets is inferior in hardness and lubricity, during press working, especially during bending and deep drawing, sliding of the resin-coated steel sheet and the die causes the resin coating to be removed from the steel sheet. Peeling, and further, peeling of the plating layer occurs,
The problem that black matter is generated, adheres to the product, or accumulates in the mold has not been solved. Similarly, with respect to abrasion resistance, it is difficult to prevent scratches caused by rubbing of steel sheets with each other due to vibration under extreme pressure.

In the fourth prior art, an ethylene-based resin having a carboxyl group is neutralized with sodium ions to form an ionomer, whereby a barrier effect due to the resin film is exhibited and corrosion resistance is not deteriorated. Blackening phenomenon of zinc plating under environment, that is,
It has improved resistance to blackening. Further, it is assumed that the flaw resistance of the coating surface can be slightly improved by making the resin component of the resin coating into an ionomer, but the blackening resistance and the abrasion resistance during press working have not been improved yet.

The fifth prior art is a technology relating to a lubricated steel sheet for the purpose of improving press workability, and a remarkable effect can be expected in suppressing blackening and abrasion during press working. However, since the surface of the fluororesin particles used as a lubricant is inactive and it is difficult to chemically bond to the inside or surface of the resin coating, it may be treated by electrodeposition coating or powder coating. There is a problem in coating film adhesion (paintability) when a paint is applied to the surface. When wax particles are used as the lubricant, when the resin coating is applied and dried, when the heating temperature is high, the wax particles in the resin coating are softened and float on the surface of the coating and solidify. And corrosion resistance deteriorates. Therefore, since the dry film forming temperature of the resin film is limited to the softening point of the used wax or lower, there is a problem that sufficient film strength cannot be obtained.

[0012]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems in conventional resin-coated metal sheets, especially resin-coated steel sheets, and it has only abrasion resistance. Excellent in press workability and punching workability such as lubricity, scratch resistance, punching resistance, blackening resistance at the time of processing, corrosion resistance, paintability, earthing property, etc. An object of the present invention is to provide a well-balanced resin-coated metal sheet, particularly a resin-coated steel sheet, and a method for producing such a resin-coated metal sheet, particularly a resin-coated steel sheet.

[0013]

According to the present invention, ions
Interpolymer-Associated Polyolefin-based Copolymers with Clusters
Mainly composed of combined resin emulsion, in terms of solid content,
5-30% by weight of silica particles and spherical polyethylene wax
Organization having 0.5-20% by weight of particles and aziridinyl group
The resin coating containing 1 to 20% by weight of the compound has a dry weight of 0.
2-2.5 g / m ²On the surface of the metal plate with an adhesion amount in the range of
The resin coated metal plate, which is characterized by being made
Be done.

Furthermore, according to the present invention, the polyolefin-based copolymer resin emulsion in which intermolecular associations are formed by ionic clusters is the main component, and 5 to 30% by weight of silica particles and 0.5 of spherical polyethylene wax particles are calculated in terms of solid content. ~
Organic compounds 1-2 having 20% by weight and an aziridinyl group
A water-based resin coating containing 0% by weight is applied to the surface of the metal plate, the metal plate is heated, the coating is dried, and the amount of coating adhered is 0.
There is provided a method for producing a resin-coated metal plate, which comprises forming a resin coating film on the surface of the metal plate at 2-2.5 g / m ² .

Hereinafter, a steel plate will be described as a representative of metal plates. In the present invention, a polyolefin-based copolymer resin emulsion in which intermolecular association by ion clusters is used as a resin component in the resin coating, and the polyolefin-based copolymer resin contains an ethylenically unsaturated carboxylic acid component. Olefin-ethylenically unsaturated carboxylic acid copolymer resin which is contained in the range of 1 to 40% by weight and may contain a (meth) acrylic acid ester component is ionized, and further crosslinked with a crosslinking agent to give a high molecular weight. It is preferably a polyolefin-based copolymer resin obtained by polymerization.

The polyolefin-based copolymer resin emulsion in which intermolecular association by the above-mentioned ion clusters is carried out is the first step of producing a polyolefin-based copolymer having a carboxyl group, and the thus obtained polyolefin-based copolymer is ionomerized. It can be obtained by going through the third step of: and the third step of increasing the molecular weight of the ionomer resin thus obtained.

The polyolefin-based copolymer resin emulsion in which intermolecular associations by the ionic clusters are obtained in this manner are added with a predetermined amount of silica particles, spherical polyethylene wax particles and an organic compound having an aziridinyl group, respectively. As a water-based resin coating material, according to the present invention, this water-based resin coating material is applied to the surface of a metal plate, the metal plate is heated to a predetermined plate temperature, and the coating material is dried to form a resin film, It is possible to obtain a resin-coated steel sheet having not only the desired ablation resistance but also a coating performance having a good balance of workability, blackening resistance during processing, punching resistance, corrosion resistance, paintability and the like.

First, the step of producing a copolymer, which is the first step in the production of a polyolefin-based copolymer resin emulsion in which intermolecular associations are caused by ion clusters, will be described. An olefin as the first monomer, and a second
1 to 40 ethylenically unsaturated carboxylic acid as a monomer of
% By weight, and, if necessary, a monomer mixture comprising another copolymerizable third monomer component in an aqueous dispersion medium at a temperature of 200 to 300 ° C. and a pressure of 1000 to 2000 atm. And copolymerized to prepare a polyolefin-based copolymer resin emulsion having a carboxyl group.

Here, examples of the ethylenically unsaturated carboxylic acid include (meth) acrylic acid, maleic acid,
Although fumaric acid, itaconic acid and the like can be mentioned, (meth) acrylic acid is particularly preferably used. Among them, (meth) acrylic acid is preferably used. Also,
Usually, as the olefin, an aliphatic α-olefin such as ethylene or propylene or an aromatic vinyl compound such as styrene is preferably used. Therefore, preferable polyolefin-based copolymer resins used in the present invention include, for example, ethylene- (meth) acrylic acid copolymer resin, styrene- (meth) acrylic acid copolymer resin, ethylene-styrene- (meth) acrylic acid. Examples thereof include copolymer resins.

In the present invention, in addition to the above-mentioned first and second monomers, if necessary, as the third monomer, for example, methyl (meth) acrylate, ethyl (meth) acrylate may be used. , (Meth) acrylic acid esters such as propyl (meth) acrylate, styrene-based monomers such as styrene, vinyltoluene, chlorostyrene, hydroxyethyl (meth) acrylate, (meth) acrylic acid hydroxypropyl, and the like. ) Hydroxyalkyl acrylate, N-substituted (meth) acrylamide such as N-methylol (meth) acrylamide, epoxy group-containing (meth) acrylic acid ester such as glycidyl (meth) acrylate, (meth) acrylonitrile or the like, or Two or more kinds can be used.

In such a polyolefin-based copolymer resin, when the amount of the ethylenically unsaturated carboxylic acid component is more than 40% by weight, the intermolecular due to the ion clusters obtained through the subsequent emulsion ionomer step and high molecular weight step. Even if the associated polyolefin-based copolymer resin emulsion is used as a film-forming material, the resulting resin-coated steel sheet is still insufficient in corrosion resistance. On the other hand, in the polyolefin-based copolymer resin, when the ethylenically unsaturated carboxylic acid component is less than 1% by weight, it is difficult to make the obtained polyolefin-based copolymer resin water-soluble or water-dispersible, Not suitable for use in the method of the invention.

As the aqueous dispersion medium, water or a mixture of water and a hydrophilic organic solvent is used. Examples of the hydrophilic organic solvent include lower aliphatic alcohols such as methanol, ethanol and n-propanol, glycol ethers such as ethylene glycol methyl ether, glycol esters such as ethylene glycol acetate, ethers such as tetrahydrofuran and dioxane, and dimethylformamide. , Diacetone alcohol, etc. are used.

The polyolefin copolymer resin obtained in the first step is then emulsified into an ionomer. This emulsified ionomerization is usually carried out at a temperature of 80 to 300 ° C.,
It is carried out by using an appropriate cation and, if necessary, ammonia water under a pressure of 1 to 20 atm. From the viewpoints of emulsifying property and resin performance, it is preferable to use an amine together when forming an ionomer under pressure.

The cation is preferably a metal ion, for example, an ion such as lithium, potassium, magnesium, zinc, sodium, calcium, iron or aluminum. Usually, sodium ion is particularly preferably used.

According to the present invention, in order to form a resin film having excellent abrasion resistance as well as workability, blackening resistance during processing, punching resistance, corrosion resistance, paintability, etc., on the surface of the steel sheet, It is necessary to partially crosslink the resin component in the resin coating to increase the molecular weight.

Therefore, according to the present invention, the above-mentioned ionomerized resin can be further partially crosslinked with a crosslinking agent to obtain a polyolefin-based copolymer resin having intermolecular association by ion clusters. The cross-linking agent is not particularly limited as long as it can cross-link using the carboxyl group of the resin, and any cross-linking agent can be used. Therefore, as a cross-linking agent,
For example, a methylol compound, an amine compound, an epoxy compound, a titanium compound, etc. can be mentioned. It is preferable that the crosslinking reaction is usually carried out under the conditions of a temperature of 30 to 200 ° C. and a pressure of from normal pressure to about 20 atm.

The resin-coated steel sheet according to the present invention is mainly composed of the intermolecularly associated polyolefin-based copolymer resin emulsion obtained by the ion clusters thus obtained, and has a silica content of 5 to 30% by weight in terms of solid content. A water-based resin coating containing 0.5 to 20% by weight of spherical polyethylene wax particles and 1 to 20% by weight of an organic compound having an aziridinyl group is applied onto a steel plate, heated to a predetermined plate temperature, and the coating is dried. The resin film weight after drying is 0.2-
It can be obtained by forming a resin coating on the surface of a steel sheet so that the coating amount will be in the range of 2.5 g / m ² .

The aqueous resin coating material used in the present invention thus contains the organic compound having an aziridinyl group in the range of 1 to 20% by weight in terms of solid content. When the paint is applied to a steel sheet and dried by heating, the interfacially associated polyolefin-based copolymer resin due to ion clusters, which is a resin component, is crosslinked to form a resin film having a high crosslink density, thus obtaining a resin film Has significantly improved its hardness, toughness and heat resistance.

Examples of the organic compound having an aziridinyl group used in the present invention include compounds represented by the following formulas:

[0030]

Embedded image

Trimethylolpropane tris (β-aziridinyl propionate) represented by the following formula

[0032]

Embedded image

Tris-2,4,6- (1-aziridinyl) -1,3,5-triazine represented by the following formula

[0034]

Embedded image

Tris [1- (2-methyl) represented by
Examples thereof include aziridinyl] phosphine oxide. An organic compound having such an aziridinyl group has the following formula

[0036]

[Chemical 4]

As shown in, a cross-linking reaction is carried out with the copolymer resin having a carboxyl group to form a resin film having a high cross-linking density, and the hardness, toughness and heat resistance of the resulting resin film are remarkably improved. It is possible to obtain the effect of suppressing the impact due to the sliding with the die applied during the press working or punching of the resin-coated steel sheet of the present invention and the softening of the resin coating due to the heat generation of the die. Further, the effect of improving the corrosion resistance and the chemical resistance can be obtained.

In the resin coating material used in the present invention, when the amount of the organic compound having an aziridinyl group is less than 1% by weight in terms of solid content in the coating material, the carboxyl group in the copolymer resin as described above is used. Not only the crosslinking reaction with and is insufficient, the carboxyl group reacts with sodium ions and potassium ions in the alkali compound used in the degreasing step after pressing or punching, making the coating hydrophilic, Remarkably deteriorates corrosion resistance and paintability.
On the other hand, when it exceeds 20% by weight, the crosslinking density of the coating becomes excessively high and the coating hardness excessively increases, and as a result,
It cannot follow the work deformation due to press work, etc., and cracks occur, which deteriorates corrosion resistance and paintability. Particularly, in the present invention, the amount of the organic compound having an aziridinyl group in the resin coating material is preferably in the range of 5 to 10% by weight in terms of solid content.

The resin coating material used in the present invention contains silica particles in an amount of 5 to 30% by weight in terms of solid content.
Silica particles give the resulting resin coating excellent corrosion resistance and paintability, and further improve the hardness of the resin coating, causing abrasion due to vibration during transportation, flaws on the coating during processing, and blackening. It is effective in controlling the occurrence of oxidization phenomenon. However, in the resin coating material, when the amount of silica particles is less than 5% by weight in terms of solid content, the resin coating obtained has insufficient improvement in corrosion resistance and coating property, and further, sufficient coating hardness. Therefore, abrasion resistance, scratches on the coating film during processing, occurrence of blackening phenomenon, etc. cannot be controlled. On the other hand, when it exceeds 30% by weight, the hardness of the resin coating is remarkably improved, but the proportion of silica particles in the resin coating becomes excessively large,
The film-forming property of the resin film deteriorates, cracks occur in the film, and corrosion resistance deteriorates.

Further, the silica particles act as a lubricant, which increases the friction coefficient of the coating and reduces the lubricity, which causes wear of the mold during processing and shortens the life of the mold. Becomes Particularly, in the present invention, the amount of silica particles in the resin coating is 5 to 20 in terms of solid content.
A weight% range is preferred.

In order to maximize the effects of the silica particles as described above, the silica particles should have a particle size of 1 to 200 nm.
It is preferably in the range of. The smaller the particle size of the silica particles, the higher the corrosion resistance of the coating. The effect of the silica particles is considered to be due to the fact that the resin coating is dense and has excellent adhesion, and further enhances the corrosion resistance of the resin coating. From such a viewpoint, the silica particles to be used, the smaller the particle diameter, the better, however, even if extremely fine particles are used, the above-mentioned effects are correspondingly not particularly enhanced, and therefore, In the present invention,
The silica particles usually have a particle size of 1 nm or more. On the other hand, the larger the particle size of the silica particles is, for example, the particle size of 40 to 2 known as chain silica particles.
By using the silica particles of 00 nm, the coatability of the resin coating is significantly improved. However, when it exceeds 200 nm, the surface of the coating film is roughened and a dense resin coating film cannot be formed. Further, the silica particles also act as a lubricant, which leads to deterioration of processability. Particularly, in the present invention, depending on the required coating performance, for example, when importance is attached to corrosion resistance, the particle size of silica particles is 4 to 20 n.
It is preferably in the range of m, and when importance is attached to coatability, it is preferably in the range of 40 to 200 nm.

Such silica particles are generally known as colloidal silica, and in the present invention, for example, commercially available products such as Snowtex XS, SS, 40, N, UP (manufactured by Nissan Chemical Industries, Ltd.). Goods can be used suitably.

The resin coating used in the present invention further comprises
Spherical polyethylene wax particles are 0.5 in solid content conversion
It is contained in the range of up to 20% by weight. The spherical polyethylene wax particles are effective in improving the lubricity of the obtained resin film and improving the abrasion resistance and the scratch resistance. Further, it improves the deep drawability and punchability required for press working and punching, the wear resistance of the mold, and the blackening resistance of the sliding surface at the time of working to provide excellent workability. .

However, in the resin coating material, when the amount of spherical polyethylene wax particles is less than 0.5% by weight in terms of solid content, the obtained resin coating film has insufficient lubricity, resulting in abrasion resistance and abrasion resistance. It is not possible to improve the scratch resistance and obtain satisfactory workability. On the other hand, when it exceeds 20% by weight, the obtained resin coating film has sufficient lubricity, but the coating film adhesion when it is applied by electrodeposition coating, powder coating, or silk printing. Inferior to. One of the reasons for this is that when the resin coating is applied, baked and dried, the wax softens, liquefies, and thickens at the interface between the resin coating and the coating, which causes the adhesion of the coating to deteriorate. To be Particularly, in the present invention, the amount of spherical polyethylene wax particles in the resin coating material is 1 to 1 in terms of solid content.
A range of 10% by weight is preferred.

In order to maximize the effect of the spherical polyethylene wax particles as described above, the wax particles preferably have a particle diameter in the range of 0.1 to 3 μm. When the particle size of the wax particles is smaller than 0.1 μm, a resin film having excellent lubricity cannot be obtained, and not only the resin film but also the punching property based on the wax particles in the film and the mold resistance. It is not possible to obtain the effects of improving the wear resistance and the deep drawability.

On the other hand, when the particle size of the wax particles exceeds 3 μm, it becomes difficult to disperse the wax uniformly in the resin coating, and the wax cannot be evenly dispersed in the resin coating obtained, resulting in the formation of a coating film. Adhesion to the steel plate deteriorates. Further, the adhesion of the coating film by electrodeposition coating, powder coating, silk printing, etc. is also deteriorated. In particular, in the present invention, the particle size of the spherical polyethylene wax particles in the resin coating is
The range of 0.3 to 1.0 μm is preferable.

In the present invention, the softening point of the spherical polyethylene wax particles is preferably in the range of 80 to 140 ° C. When the softening point is lower than 80 ° C, the wax particles are softened and liquefied as the mold temperature rises during press working or punching, so that the sliding surface between the resin-coated steel sheet and the mold , The liquid of the liquefied wax will run out, the workability will be deteriorated, scratches and seizure with the mold will occur, and black matter will adhere to the sliding parts, significantly deteriorating the product appearance. . On the other hand, when the softening point exceeds 140 ° C, the lubricity of the wax particles is not sufficient, and no improvement in punching property, die wear resistance, deep drawability, etc. is observed, and excellent workability can be obtained. Can not.

In the present invention, examples of such spherical polyethylene wax particles include Daijet E-17.
(Manufactured by Mutual Chemical Co., Ltd.), KUE-1, KUE-5, KU
E-8, (manufactured by Sanyo Kasei Co., Ltd.), Chemipearl W-1
00, Chemipearl W-200, Chemipearl W-300,
Chemipearl W-400, Chemipearl W-500, Chemipearl W-640, Chemipearl W-700 (manufactured by Mitsui Petrochemical Industry Co., Ltd.), Elepon E-20 (Nikaka Chemical Co., Ltd.)
Commercially available products such as manufactured products) can be preferably used.

According to the present invention, the water-based resin coating composition as described above is applied to the surface of a steel sheet and heated and dried at a plate temperature lower than the softening point of the spherical polyethylene wax particles. While maintaining the spherical polyethylene wax particles in a spherical shape in the resin coating, a resin coating is formed, and by further improving the lubricity of the resin coating thus obtained, the obtained resin-coated steel sheet can be press-formed and punched. Can be further increased. Further, by keeping the spherical polyethylene wax particles spherical in the resin coating, it becomes possible to disperse the wax particles more uniformly in the resin coating, and further, on the surface of the resin coating, the wax exposed from the resin coating. Since the surface area of the particles can be reduced and the resin film can be easily covered completely, excellent corrosion resistance and paintability can be obtained.

In order to form a conventional thermosetting resin coating on the surface of a steel sheet, baking and drying at high temperature for a long time are required. However, the resin coating used in the present invention is applied to the surface of a metal sheet and compared. By heat-drying at a relatively low temperature for a short time, a cross-linked film is formed to form a resin film having a three-dimensional network structure, and baking and drying at a high temperature for a long time as in the past are unnecessary. Therefore, according to the present invention, it is possible to manufacture the crosslinked resin-coated steel sheet with a simple drying facility, and there is an advantage that the steel sheet can be easily produced in-line.

For example, in an electrogalvanizing production line, a resin coated steel sheet can be produced by applying a resin coating material with a roll coater and drying it in a short time with simple drying equipment. In this way, in-line production and inexpensive equipment investment can be performed, which can contribute to a significant cost reduction.

In the present invention, the amount of the resin coating adhered to the steel sheet is preferably in the range of 0.2 to 2.5 g / m ² as a dry coating. When the amount of the resin coating adhered is less than 0.2 g / m ² , the resin coating cannot be uniformly applied to the steel sheet, and the abrasion resistance as well as the workability, blackening resistance, corrosion resistance and coating It is not possible to sufficiently exert the desired balanced coating performance such as the property. On the other hand, when the amount of the resin coating adhered is more than 2.5 g / m ² , for example,
The earthing property, which is one of the required characteristics of computer cases, that is, the conductivity is deteriorated. Further, in the press working, the amount of the resin coating peeled off increases, the release coating adheres and accumulates on the mold, which hinders press molding and increases the manufacturing cost. From a practical point of view, the amount of the resin film deposited is preferably in the range of 0.3 to 1.0 g / m ² .

The metal plate material used in the resin-coated metal plate according to the present invention is not particularly limited,
For example, zinc or zinc-based plated steel plate, aluminum plate,
An aluminum alloy plate, a titanium plate, etc. can be mentioned. Further, with respect to zinc or zinc-based plated steel plate, aluminum plate, aluminum alloy plate, etc., from the viewpoint of corrosion resistance, those subjected to chemical conversion treatment such as chromate treatment or phosphate treatment are preferable, but particularly those subjected to chromate treatment Is preferred. As a chromate treatment, a washing type,
(Reactive type) chromate treatment, coating type chromate treatment, and electrolytic type chromate treatment are all used.

[0054]

As described above, according to the present invention, it is possible to obtain a resin-coated steel sheet having a crosslinked resin coating by applying a water-based paint to the steel sheet and heating and drying at a relatively low temperature for a short time. it can. The resin-coated steel sheet thus obtained has not only excellent abrasion resistance, but also press working and punching work such as lubricity, scratch resistance, punching resistance, and blackening resistance during working. Has excellent corrosion resistance, paintability, groundability, and the like, and its properties are well balanced.

[0055]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.
In the following, as the metal plate material, an electrogalvanized steel sheet subjected to chromate treatment (zinc adhesion amount 20 g / m ² , chromium adhesion amount 20 mg / m ² ) in order to enable relative evaluation between the examples. Using.

The evaluation items and test methods in the examples are as follows. In the 5-point scale, 5 indicates the best and 1 indicates the worst. (1) Corrosion resistance Regarding the resin coated steel sheet obtained, a salt spray test of flat plate material and Erichsen processed material subjected to edge sealing was performed according to JIS Z2.
It was carried out according to 371 and evaluated by the time until 1% of white rust was generated. The Erichsen extrusion height of the Erichsen processed material was 6 mm. (2) Paintability The resin-coated steel sheet obtained was coated with a melamine-based paint in a thickness of 20 μm
After spray coating at, bake at 150 ℃ for 30 minutes,
After soaking in boiling water for 1 hour, take out, 1 hour later, insert a 100 mm square grid with a cutter knife after 1 hour, conduct a tape peeling test on this, and paint with the number of remaining grids The adhesion was evaluated.

(3) Dynamic Friction Coefficient In order to evaluate the lubricity of the obtained resin-coated steel sheet, a sliding tester was used to measure the load due to sliding at a pressing force of 150 kg to calculate the dynamic friction coefficient. (4) Punchability In order to evaluate the punching workability of the obtained resin coated steel sheet, a die material SKD-1 was used using a continuous punching test device.
1. A continuous punching test was carried out under the conditions of a die shape of 10 mm square, a clearance of 25%, a punching speed of 80 sheets / minute, and no punching oil used, and the number of punchings until the burr height reached 50 μm was evaluated. Further, the state of die wear after punching 1.5 million pieces was observed with a videoscope, and the die wear resistance was evaluated on a five-point scale.

(5) Workability In order to evaluate the press workability such as deep drawability of the obtained resin coated steel sheet, a crank press machine of 80 tons was used.
A single-shot press test was performed, and the sliding surface of the molded product after molding was visually evaluated for scratches, mold scuffing, and blackening resistance on a 5-grade scale. (6) Coating hardness A pencil scratch test was conducted on the surface of the obtained resin-coated steel sheet according to JIS K5400, and the hardness of the resin coating on the surface of the resin-coated steel sheet was evaluated by pencil hardness.

(7) Earthing property The terminals of the tester (+,
-) Was placed lightly and the resistance value of the surface when sliding was measured, and the earthing property was evaluated on a 5-point scale. (8) Abrasion resistance Using a PWO type plane bending fatigue tester, abrasion was generated and the ablation resistance was visually evaluated on a five-point scale. (9) Resin film strength Using a resin paint, prepare a film with a thickness of 40 μm,
Tensile load (film width 1
5 mm, 50 mm between chucks, and 20 ° C.) were measured.

Example 1 A polyolefin copolymer resin having a carboxyl group having an ethylenically unsaturated carboxylic acid component in the range of 0.5 to 50% by weight was ionomerized with sodium hydroxide, and further crosslinked with a crosslinking agent. Polymerization was carried out to prepare a polyolefin-based copolymer resin emulsion in which intermolecular association was formed by ion clusters.

In addition to this, the particle size in terms of solid content is 10 to 20n.
m silica particles 10% by weight, softening point 100 ° C., particle size 0.
An aqueous resin coating material was prepared by adding 5% by weight of 6 μm spherical polyethylene wax particles and 10% by weight of trimethylolpropane tris (β-aziridinyl propionate). This resin coating is applied to the surface of the chromate-treated electrogalvanized steel sheet, which is heated and dried at a plate temperature of 90 ° C.
A resin-coated steel sheet having a resin coating film with an adhesion amount of 1 g / m ² was obtained. Table 1 shows the corrosion resistance and coatability of the resin-coated steel sheet thus obtained.

[0062]

[Table 1]

Example 2 A polyolefin-based copolymer resin having a carboxyl group containing 20% by weight of an ethylenically unsaturated carboxylic acid component was ionized with sodium hydroxide and further polymerized with a crosslinking agent to give an ion cluster. A polyolefin-based copolymer resin emulsion with intermolecular association was prepared.

The particle size is 10 to 20n in terms of solid content.
m silica particles 10% by weight, softening point 100 ° C., particle size 0.
An aqueous resin coating material was prepared by adding 5% by weight of 6 μm spherical polyethylene wax particles and trimethylolpropane tris (β-aziridinylpropionate) (TAZM) in the range of 0.5 to 25% by weight. This resin paint was applied to the surface of the chromate-treated electrogalvanized steel sheet and dried by heating at a temperature of 90 ° C. to obtain a resin-coated steel sheet having a resin coating film having an adhesion amount of 1 g / m ² . Table 2 shows the corrosion resistance and coatability of the resin-coated steel sheet thus obtained.

[0065]

[Table 2]

Example 3 A polyolefin copolymer resin having a carboxyl group containing 20% by weight of an ethylenically unsaturated carboxylic acid component was ionomerized with sodium hydroxide and further polymerized with a crosslinking agent to give an ion cluster. A polyolefin-based copolymer resin emulsion with intermolecular association was prepared.

The particle size is 10 to 20n in terms of solid content.
m silica particles were added over the range of 3 to 35% by weight, 5% by weight of spherical polyethylene wax particles having a softening point of 100 ° C. and a particle size of 0.6 μm, and trimethylolpropane tris (β-aziridinyl propionate) 10 % By weight was added to prepare an aqueous resin paint. This resin coating is applied to the surface of the chromate-treated electrogalvanized steel sheet, dried by heating at a temperature of 90 ° C., and an adhesion amount of 1 g / m ²
A resin-coated steel sheet having the resin coating of was obtained. Table 3 shows the corrosion resistance and coatability of the resin-coated steel sheet thus obtained.

[0068]

[Table 3]

Example 4 A polyolefin-based copolymer resin having a carboxyl group containing 20% by weight of an ethylenically unsaturated carboxylic acid component was ionized with sodium hydroxide and further polymerized with a crosslinking agent to give an ion cluster. A polyolefin-based copolymer resin emulsion with intermolecular association was prepared.

In addition, the particle size in terms of solid content is 4 to 400.
10% by weight of silica particles and a softening point of 10
An aqueous resin coating material was prepared by adding 5% by weight of spherical polyethylene wax particles having a particle diameter of 0.6 μm at 0 ° C. and 10% by weight of trimethylolpropane tris (β-aziridinyl propionate). This resin paint was applied to the surface of the chromate-treated electrogalvanized steel sheet and dried by heating at a temperature of 90 ° C. to obtain a resin-coated steel sheet having a resin coating film having an adhesion amount of 1 g / m ² . Table 4 shows the corrosion resistance and coatability of the resin-coated steel sheet thus obtained.

[0071]

[Table 4]

Example 5 A polyolefin copolymer resin having a carboxyl group containing 20% by weight of an ethylenically unsaturated carboxylic acid component was ionomerized with sodium hydroxide, and further polymerized with a crosslinking agent to give an ion cluster. A polyolefin-based copolymer resin emulsion with intermolecular association was prepared.

The particle size is 10 to 20n in terms of solid content.
m silica particles 10% by weight, softening point 100 ° C., particle size 0.
6 μm spherical polyethylene wax particles were added over a range of 0.3 to 25% by weight and trimethylolpropane tris (β-aziridinyl propionate) 10
A weight percent was added to prepare an aqueous resin coating. This resin coating is applied to the surface of the chromate-treated electrogalvanized steel sheet, dried by heating at a temperature of 90 ° C., and the adhesion amount is 1 g / m 2.
A resin-coated steel sheet having a resin coating of ² was obtained. Table 5 shows the corrosion resistance and coatability of the resin-coated steel sheet thus obtained.

[0074]

[Table 5]

Example 6 A polyolefin copolymer resin having a carboxyl group containing 20% by weight of an ethylenically unsaturated carboxylic acid component was ionomerized with sodium hydroxide and further polymerized with a crosslinking agent to give an ion cluster. A polyolefin-based copolymer resin emulsion with intermolecular association was prepared.

The particle size is 10 to 20n in terms of solid content.
m silica particles with a softening point of 100 ° C. and a particle size of
10% by weight of spherical polyethylene wax particles ranging from 0.1 to 3 μm and 10% by weight of trimethylolpropane tris (β-aziridinyl propionate) were added,
An aqueous resin paint was prepared. This resin coating is applied to the surface of the chromate-treated electrogalvanized steel sheet at a temperature of 9
It was dried by heating at 0 ° C. to obtain a resin-coated steel sheet having a resin coating film having an adhesion amount of 1 g / m ² . Table 6 shows the corrosion resistance and coatability of the resin-coated steel sheet thus obtained.

[0077]

[Table 6]

Example 7 A polyolefin copolymer resin having a carboxyl group containing 20% by weight of an ethylenically unsaturated carboxylic acid component was ionized with sodium hydroxide and further polymerized with a crosslinking agent to give an ion cluster. A polyolefin-based copolymer resin emulsion with intermolecular association was prepared.

The particle size is 10 to 20n in terms of solid content.
10% by weight of silica particles, 10% by weight of spherical polyethylene wax particles having a softening point of 70 to 150 ° C. and a particle size of 0.6 μm, and 10% by weight of trimethylolpropane tris (β-aziridinyl propionate). % Was added to prepare an aqueous resin paint. This resin coating is applied to the surface of the chromate-treated electrogalvanized steel sheet,
It was heated and dried at a temperature of 90 ° C. to obtain a resin-coated steel sheet having a resin coating film having an adhesion amount of 1 g / m ² . Table 7 shows the corrosion resistance and coatability of the resin-coated steel sheet thus obtained.

[0080]

[Table 7]

Example 8 A polyolefin-based copolymer resin having a carboxyl group containing 20% by weight of an ethylenically unsaturated carboxylic acid component was ionomerized with sodium hydroxide and further polymerized with a crosslinking agent to give an ion cluster. A polyolefin-based copolymer resin emulsion with intermolecular association was prepared.

The particle size is 10 to 20 n in terms of solid content.
m silica particles 10% by weight, softening point 100 ° C., particle size 0.
An aqueous resin coating material was prepared by adding 10% by weight of 6 μm spherical polyethylene wax particles and 10% by weight of trimethylolpropane tris (β-aziridinyl propionate). This resin coating is applied to the surface of the chromate-treated electrogalvanized steel sheet, heat-dried at a temperature of 90 ° C., and a resin-coated steel sheet having a resin coating film with an adhesion amount in the range of 0.2 to 2.5 g / m ^2. Got Table 8 shows the corrosion resistance and coatability of the resin-coated steel sheet thus obtained.

[0083]

[Table 8]

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Claims (12)

[Claims] 1. A polyolefin-based copolymer resin emulsion, which is intermolecularly associated with an ionic cluster, as a main component, in terms of solid content, 5 to 30% by weight of silica particles, 0.5 to 20% by weight of spherical polyethylene wax particles and aziridinyl. A resin coating containing 1 to 20% by weight of an organic compound having a group is formed on the surface of the metal plate with an adhesion amount in the range of 0.2 to 2.5 g / m ^{2 in} dry weight. A resin-coated metal plate that does. 2. A polyolefin-based copolymer resin emulsion in which intermolecular association by ionic clusters is contained, in the range of 1 to 40% by weight of an ethylenically unsaturated carboxylic acid component,
A polyolefin-based copolymer resin emulsion obtained by ionizing an olefin-ethylenically unsaturated carboxylic acid copolymer resin that may contain a (meth) acrylic acid ester component, and further crosslinking it with a crosslinking agent to increase the molecular weight. The resin-coated metal plate according to claim 1, wherein 3. The resin-coated metal plate according to claim 2, wherein the olefin is at least one selected from ethylene and styrene. 4. The resin-coated metal plate according to claim 1, wherein the silica particles have a particle size in the range of 1 to 200 nm. 5. The spherical polyethylene wax particles are 0.1 to 3
The resin-coated metal plate according to claim 1, which has a particle size in the range of μm. 6. Spherical polyethylene wax particles are 80 to 1
The resin-coated metal sheet according to claim 1, which has a softening point in the range of 40 ° C. 7. A polyolefin-based copolymer resin emulsion intermolecularly associated with an ionic cluster as a main component, in terms of solid content, 5 to 30% by weight of silica particles, 0.5 to 20% by weight of spherical polyethylene wax particles and aziridinyl. An aqueous resin paint containing 1 to 20% by weight of an organic compound having a group is applied to the surface of a metal plate, the metal plate is heated, the paint is dried, and the coating amount is 0.2 to 2.5 g / m ^2. 2. A method for producing a resin-coated metal plate, which comprises forming a resin coating on the surface of the metal plate according to 1. 8. A polyolefin-based copolymer resin emulsion in which intermolecular association by ionic clusters is contained, in the range of 1 to 40% by weight of an ethylenically unsaturated carboxylic acid component,
A polyolefin-based copolymer resin emulsion obtained by ionizing an olefin-ethylenically unsaturated carboxylic acid copolymer resin that may contain a (meth) acrylic acid ester component, and further crosslinking it with a crosslinking agent to increase the molecular weight. The method for producing a resin-coated metal plate according to claim 7, wherein 9. The method for producing a resin-coated metal plate according to claim 8, wherein the olefin is at least one selected from ethylene and styrene. 10. The method for producing a resin-coated metal plate according to claim 7, wherein the silica particles have a particle size in the range of 1 to 200 nm. 11. Spherical polyethylene wax particles are 0.1-
The method for producing a resin-coated metal plate according to claim 7, which has a particle size in the range of 3 μm. 12. The resin-coated metal sheet according to claim 7, wherein the metal sheet is heated at a temperature lower than the softening point of the spherical polyethylene wax particles to retain the spherical polyethylene wax particles in a spherical shape in the resin coating. Manufacturing method.