JP2000280400A - Coating composition and lubricating treatment metal panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating compsn. improved in alkali film removing properties, coating film drying propertiers, blocking resistance, rustproofness, coating stability and press processability and a lubricating treatment metal panel using the same. SOLUTION: A coating compsn. contains an acrylic resin and a neutralizing agent. The acrylic resin includes metacrylic acid ester consisting of methacrylic acid and 2 or more C alcohol, styrene and a copolymer monomer having a carboxyl group, a copolymer of at least one component selected from maleic acid, fumaric acid, itaconic acid and monoalkyl ester of them and syrene and a polymer of a polymerizable compd. having an ether bond.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition and a lubricated metal sheet having a coating film formed by applying the coating composition to the surface, and more particularly to a galvannealed steel sheet, Rolled steel sheet, cold rolled steel sheet, plated steel sheet,
When applied to stainless steel plates and aluminum plates, presses with powdering resistance and mold galling resistance while maintaining alkali film removal, chemical conversion, rust prevention, coating drying and blocking resistance The present invention relates to a coating composition capable of improving moldability and a lubricated metal plate obtained by applying the same to various metal plates.

[0002]

2. Description of the Related Art Conventionally, galvanized steel sheets (electroplated steel sheets and galvannealed steel sheets) have been used for automobile structural materials and parts that require high rust resistance. In recent years, the use of alloyed hot-dip galvanized steel sheets has been increasing from the viewpoint of cost reduction as a substitute for parts employing electric galvanized steel sheets. However, conventionally, the galvannealed steel sheet has a large dynamic friction coefficient and is inferior in press formability as compared with the electroplated steel sheet. there were.

That is, the range in which press molding can be performed is narrowed. Peeling of the plating layer, that is, powdering, occurs at the sliding portion between the mold and the steel plate. In the worst case, mold seizure occurs, and the mold is contaminated and damaged, so that the frequency of repairing the mold increases, and at the same time, the quality of the molded product deteriorates. Therefore, in order to use an alloyed hot-dip galvanized steel sheet, it is necessary to improve press formability including powdering resistance and mold galling resistance. Further, with respect to hot-rolled steel sheets, cold-rolled steel sheets, electrogalvanized steel sheets, and electrogalvanized-nickel-plated steel sheets, studies are being made on further improving press formability by improving lubrication characteristics (dynamic friction coefficient). However, it is difficult to achieve this by using rust preventive oil or press oil.

[0004] On the other hand, demand for aluminum sheets is expected to increase in the current trend of reducing the weight of automobile bodies. However, at present, aluminum sheets are inherently small in elongation, and therefore, applicable parts are limited. Have been. Further, the stainless steel sheet is often used after being subjected to deep drawing, such as a bathtub or a washing tub of a washing machine. At present, a polyvinyl chloride film is attached to the die side of the steel plate before molding to prevent mold galling due to contact with the mold.However, it is necessary to peel off the vinyl chloride film from the molded product after press molding. In addition, there is a problem that environmental pollution is caused depending on a disposal method of the peeled film. Therefore, in order to improve the press formability of each metal plate, it has been proposed to apply an organic resin coating to improve the lubricity of the metal plate.

These organic resin-coated metal sheets are press-formed by a customer, then the organic resin coating film is removed by alkali washing, that is, alkali-removed, and then a chemical conversion coating is formed by phosphoric acid treatment or the like. After that, it is coated by electrodeposition coating or spray coating. Through such a surface treatment step, the adhesion between the exterior coating film and the metal plate is ensured. Further, rusting during the storage period until the consumer uses the organic resin-coated metal plate also poses a problem. In recent years, from the viewpoint of cost reduction emphasis, the organic resin coating film has a low temperature and
It is desired to be formed by baking for a short time, and a coating film drying property has been required. The organic resin-coated metal plate is often stored in a state where a large load is applied, with the coating surfaces being in contact with each other in a band or plate shape immediately after the formation of the coating,
In this case, it must be avoided that it cannot be peeled off during use. That is, blocking resistance is also required.

[0006] In order to satisfy the above characteristics, there have been many proposals for forming a coating film such as an organic film composition of an alkali delamination type on a steel sheet surface, for example, Japanese Patent Publication No. 53-37817.
JP-A-6-84193, JP-A-3-2193
03996, JP-A-5-194988 and the like. JP-A-5-194983 discloses an organic resin coating composition containing two types of esterified products obtained by esterifying a specific styrene-maleic acid copolymer with a hydroxyl group-containing compound having an alkyl group or an alkenyl group. Attempts have been made to solve the above problem by applying an object. However, since this copolymer has a low molecular weight, the breaking strength of the coating film is small and the press formability is poor. In particular, when the temperature of the mold rises, there is a problem that the press formability is significantly reduced.

Further, Japanese Patent Publication No. 53-37817, Japanese Patent Application Laid-Open No. 62-84193 and Japanese Patent Application Laid-Open No. 3-203996 disclose that an organic resin is specified to improve press moldability, and that a carboxyl group in the organic resin is improved. There has been proposed a technique for ensuring the alkali film-removing property by its existence and further by defining this acid value. For example, Japanese Patent Publication No. 53-37
The organic resin described in Japanese Patent No. 817 is a water-soluble copolymer composed of an acrylate ester, methyl methacrylate, styrene and a carboxyl group-containing monomer, having a weight average molecular weight of 15,000 to 50,000 and a glass transition. Point Tg is 60 to 90
° C. However, in these techniques, the formation of crystals of the chemical conversion coating film after the alkali washing is insufficient, and there is a problem in press formability, particularly in press formability in a warm state.

[0008]

The problems of the prior art described above are summarized as follows, and it is an object of the present invention to solve these problems. <Press formability (powdering resistance and galling resistance)> At the time of continuous pressing for hundreds to thousands of times or remarkable deep drawing at the customer, the mold temperature is at least due to frictional heat and deformation resistance. It is said that the temperature rises to 40 ° C. and sometimes 100 ° C. In order to alleviate this temperature rise, press molding is generally performed while applying oil to a mold. However, as the number of presses increases, the cooling effect of the oil decreases and the mold temperature increases. As a result, the conventional technique has a problem that the organic resin coating film is softened, the lubrication performance is reduced, and press cracking, powdering, and mold seizure occur.

<Alkali film-removing property (alkali film-removing property / chemical conversion property)> In a consumer, after press molding, alkali cleaning treatment and chemical conversion treatment are performed to form a chemical conversion-treated film crystal, and then electrodeposition coating. It is necessary to secure the adhesion between the coating film of the exterior paint and the metal plate by electrostatic coating or the like. In order to form a chemical conversion coating, the organic resin coating must be removed, and it is important to remove the organic resin coating by alkali washing before the chemical conversion treatment (alkali removal).

Particularly, in a galvanized steel sheet, the ionic bond between the zinc in the plating layer and the carboxyl group contained in the organic resin significantly reduces the alkali film-removing property, making it difficult to completely remove the organic resin coating film. For this reason, even if the water wettability after the alkali washing is sufficient, the problem of the shape of the chemical conversion treatment film crystal and the shortage of the adhesion amount occur. Such a problem commonly exists in the above-mentioned prior art.

<Rust prevention> In order to ensure alkali film removal,
When the carboxyl group is left in the organic resin coating film as in the prior art, the problem is that the coating film absorbs moisture in the atmosphere and rusts from shipment of the metal plate to use by the customer. was there.

The present invention is concerned with the problems that have been left in a metal plate having an organic resin coating film (lubricated coating film) on the metal plate surface, namely, alkali film removal properties, chemical conversion treatment properties, press moldability (powder resistance). A coating composition capable of remarkably improving the ring resistance, mold galling resistance), rust prevention, and even coating drying and blocking resistance, and lubrication having an organic resin coating formed by applying the coating composition to the surface of a metal plate. It is an object to provide a treated metal plate together.

[0013]

The above object is easily solved by the following means. That is, the present invention provides a coating composition containing an acrylic resin and a neutralizing agent,
The acrylic resin is a methacrylic acid ester composed of methacrylic acid and an alcohol having 2 or more carbon atoms, a copolymer (a) of styrene and a monomer having a carboxyl group, maleic acid, fumaric acid, itaconic acid and the like. A coating composition comprising a copolymer (b) composed of at least one monoalkyl ester of styrene and styrene and a polymer (c) of a polymerizable compound having an ether bond.

The present invention also provides a coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin has a methacrylic acid ester comprising methacrylic acid and an alcohol having 2 or more carbon atoms, styrene, and an ether bond. (D) with a polymerizable compound having a carboxyl group and a monomer having at least one selected from maleic acid, fumaric acid, itaconic acid and monoalkyl esters thereof with styrene A coating composition characterized by containing a coalescence (b).

The present invention also relates to a coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin contains methacrylic acid ester composed of methacrylic acid and an alcohol having 2 or more carbon atoms, styrene, and a carboxyl group. And a copolymer (e) with one or more selected from maleic acid, fumaric acid, itaconic acid and monoalkyl esters thereof, and a polymer (c) of a polymerizable compound having an ether bond. ).

Further, the present invention provides a coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin comprises methacrylic acid ester comprising methacrylic acid and an alcohol having 2 or more carbon atoms, styrene, and a carboxyl group. A copolymer with a monomer having the formula (a), maleic acid,
A coating composition comprising a copolymer (f) of at least one selected from fumaric acid, itaconic acid and monoalkyl esters thereof, styrene, and a polymerizable compound having an ether bond. .

The present invention also provides a coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin has a methacrylic acid ester comprising methacrylic acid and an alcohol having 2 or more carbon atoms, styrene, and an ether bond. A polymerizable compound, a monomer having a carboxyl group, and a copolymer (g) with at least one selected from maleic acid, fumaric acid, itaconic acid and monoalkyl esters thereof. Paint composition.

Further, the present invention is a lubricated metal plate having a coating film formed by applying any one of the above-mentioned coating compositions to the surface.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the coating composition and lubricated metal sheet of the present invention will be described in detail. The present invention relates to a coating composition containing an acrylic resin and a neutralizing agent. The metal sheet to be improved has press formability (powdering resistance, mold galling resistance), rust prevention and blocking resistance. The study was conducted with emphasis on enhancing the performance of a copolymer in which methacrylate and styrene were introduced into the base of an acrylic resin.

On the other hand, with respect to the improvement of alkali film-removing property, chemical conversion property and coating film drying property, acrylic resin is selected from monomers having a carboxyl group, maleic acid, fumaric acid, itaconic acid and alkyl esters thereof. 1
More than one kind, or a polymerizable compound having an ether bond,
The study was conducted with emphasis on introduction or inclusion as a component constituting the copolymer. Further, the coating composition of the present invention contains a neutralizing agent which is a base such as ammonia and amines for neutralizing the acrylic resin of the present invention. Therefore, the coating composition of the present invention does not require the use of a surfactant as described below. Further, the coating composition of the present invention may contain one or more kinds of additives, rust inhibitors, lubricants, coloring agents and the like which are usually added to coatings.

Water-soluble copolymer (a) The present inventors have studied an acrylic resin from the viewpoint of press moldability. As a result, the copolymer of methacrylic acid ester, styrene and a monomer having a carboxyl group is It has been found that it is possible to maintain the breaking energy of the organic resin coating film at a high level, which is effective for improving the press formability. It has also been found that limiting the alcohol to be esterified with methacrylic acid to alcohols having 2 or more carbon atoms is effective in ensuring rust prevention. In the case of a methyl group having 1 carbon atom, rust prevention is extremely reduced. This is presumably because the methyl group increases the polarization of the ester group, and as a result, the interaction with water increases. As the alcohol having 2 or more carbon atoms, an aliphatic monohydric alcohol is practical. As the methacrylic acid ester of the present invention, ethyl methacrylate (abbreviation: EMA: Tg 65 ° C.), isopropyl methacrylate (abbreviation: iso-PMA: Tg81) C), n-butyl methacrylate (abbreviated as n-BMA: Tg20)
C), isobutyl methacrylate (abbreviated as iso-BMA:
Tg 67 ° C.).

Acrylic esters usually have a glass transition point Tg of less than 0 ° C. and tend to have poor press moldability. In the present invention, a methacrylic acid ester is indispensable, and a methacrylic acid ester having a Tg of 0 ° C. or more is preferable because it has excellent press moldability. Generally, actual press forming by a customer is continuous and at a high speed, and the temperature of a metal plate or a mold may reach 100 ° C. due to frictional heat or heat due to deformation resistance of a metal plate. Therefore, when a copolymer containing a methacrylic ester having a Tg of less than 0 ° C. as a component is contained, this soft component is separated or melted from the metal plate by heat, and the lubrication performance of the entire coating film is reduced. Become. The Tg of the methacrylic acid ester is preferably in the range from 10C to 90C.

Styrene, which is the second copolymer component of the copolymer (a), has high moisture resistance and a high glass transition point Tg.
It is essential to achieve both rust prevention and press formability.
The copolymerization ratio of the methacrylate and styrene is preferably from 10:90 to 90:10 by weight. If the ratio of the methacrylic acid ester is less than 10% by weight in the total amount of both, the content ratio of styrene increases, so that the press formability and the rust prevention property are improved. The alkali film-removing property tends to decrease, and the storage stability of the paint tends to decrease. On the other hand, when the content exceeds 90% by weight, the rupture strength of the coating film is reduced, the press formability is reduced, and at the same time, the hydrophobicity of the coating film is reduced, so that the rust resistance is reduced. More preferred weight ratio of methacrylate: styrene is 30: 70-8.
5:15, more preferably 50: 50-8.
0:20.

The third copolymer component of the copolymer (a) is a monomer having a carboxyl group, for example, ethylene having one or two carboxyl groups such as acrylic acid, methacrylic acid, maleic acid and itaconic acid. Unsaturated carboxylic acids. As a result, the copolymer has a carboxyl group in the molecule, and can be made water-soluble by neutralizing with a base such as ammonia or amine. As a result, the copolymer (a) has an alkali film-removing property, which is one of the important properties of the paint.

The copolymer (a) has an acid value before neutralization of 20 to
It is preferable to adjust so as to be 300 mg-KOH / g. When the acid value is less than 20 mg-KOH / g, the alkali film-removing property of the coating film with an alkaline cleaning liquid is extremely reduced. In addition, the water solubility of the copolymer (a) itself is low, and it is difficult to form a coating by making the copolymer water-soluble. On the other hand, the acid value is 300m
If it exceeds g-KOH / g, the rust-preventing property of the coating film is extremely reduced, and the effects of styrene and other rust-preventing agents are not exhibited. More preferred acid value is 25 to 250 mg-K
OH / g, and further 100 to 230 mg-KOH / g
It is. In order to secure the above-mentioned preferable acid value, for example, in the case of methacrylic acid, methacrylic acid may be 4 to 50 parts by weight based on 100 parts by weight of the copolymer (a) of methacrylic acid, styrene and methacrylic acid ester. .

The preferred molecular weight of the copolymer (a) is
It is 10,000 to 60,000 in weight average molecular weight. Within this range, the lubricating performance of the coating film is effectively exhibited, which is preferable for press formability. Further, in the copolymer (a), the carboxyl group is made water-soluble by a neutralizing agent which is a base such as ammonia or amine. Therefore, it is not necessary to use a surfactant used for emulsification or the like. Therefore, the surfactant remains in the dried coating film, and there is no problem of deteriorating the rust prevention and press moldability of the coating film. In addition, as the essence of the emulsion paint containing a surfactant, it is necessary to set the drying baking temperature to (Tg + 20 ° C.) or more, and a film can be formed only by drying at a higher temperature. This means that when the surfactant is contained, the drying property of the coating film is inferior. In the case of the copolymer (a), this problem is also avoided.

The copolymer (a) can be obtained by known solution polymerization in an aqueous solvent. For example, under a nitrogen atmosphere, methacrylic acid ester and styrene are adjusted in an aqueous solvent (for example, butyl cellosolve) adjusted to 80 to 140 ° C., and the weight ratio of methacrylic acid ester: styrene is preferably adjusted to 10:90 to 90:10. And a monomer having a carboxyl group, preferably having an acid value of 2
The copolymerization was carried out with the polymerization initiator dropwise over 4 to 5 hours so as to be 0 to 300 mg-KOH / g, and the mixture was further heated and stirred at the same temperature for 2 to 8 hours to complete the copolymerization. A combination (a) is obtained. Thereafter, the solution was
The solution is cooled to 、 60 ° C., neutralized with a base such as ammonia or amine, and made water-soluble.

Preferred neutralizing agent When the metal sheet to which the coating composition is applied is an alloyed hot-dip galvanized steel sheet, as described above, the interaction between zinc in the plating layer and the carboxyl group of the coating composition. , There is a tendency for the alkali film-removing property to decrease. In the coating composition, from the viewpoint of improving the rust resistance of metal plates and press formability,
It is required to improve the breaking strength of the organic resin coating film. Therefore, when the Tg and the molecular weight of the copolymer (a) are increased, the alkali film-removing property of the organic resin coating film is reduced. This can be improved by specifying a neutralizer, adding a copolymer (b), and further adding a polymer (c) of a polymerizable compound having an ether bond.

When the alkali washing in the consumer is performed at a temperature lower than the Tg of the copolymer (a) and for a relatively short time, no matter how much the number of carboxyl groups not neutralized by the neutralizing agent is increased. In addition, the alkali film removal property becomes poor. Therefore, if the carboxyl group can be maintained in a neutralized state even after the organic resin coating, the alkali film-removing property can be improved. Therefore, by neutralizing a part of the carboxyl groups in the organic resin coating with a base that does not easily evaporate during the coating of the organic resin, that is, an amine or hydroxide having a high boiling point, the hydrophilic substance is contained in the organic resin coating. It is preferable because it can be introduced. The use of these neutralizing agents assists the penetration of alkali into the organic resin coating film during alkali cleaning, and enables alkali removal at a low temperature in a short time.

When the boiling point of the amine as a neutralizing agent is less than 30 ° C., the amine volatilizes even when the organic resin coating film is dried at room temperature, and the alkali film-removing property deteriorates. More preferred is an amine having a boiling point of 100 ° C. or higher, and more preferred is 160 or more.
It is an amine of not less than ° C. Examples of amines having a boiling point of 30 ° C. or higher include isopropylamine (boiling point 32 ° C.), diethylamine (boiling point 56 ° C.), N, N-dimethylethanolamine (boiling point 130 ° C.), and monoethanolamine (boiling point 17 ° C.).
0 ° C.), triisopropanolamine (bp 305
° C), triethanolamine (boiling point 360 ° C) and the like, with alkanolamine and alkylamine being particularly preferred. Examples of the hydroxide include sodium hydroxide and potassium hydroxide.

The neutralizing agent is added in an amount of 0.6% of ammonia to 1 equivalent of the acid contained in the resin solid content of the copolymer (a).
It is preferred that the amine or hydroxide having a boiling point of 30 ° C. or higher is 0.05 to 0.5 equivalents. When the amount of the amine or hydroxide having a boiling point of 30 ° C. or more is 0.05
If the amount is less than the equivalent, it is difficult to secure alkali film-removing properties under alkali washing in a short time, and conversely, it is not preferable that the amount of the alkali film is 0.1.
If it exceeds 5 equivalents, the breaking strength of the coating film decreases, the press formability decreases, and the productivity decreases. Further, the blocking resistance is also reduced. A more preferable addition amount of the amine or hydroxide having a boiling point of 30 ° C. or more is 0.1 to 0.4 equivalent. On the other hand, if the amount of ammonia is less than 0.6 equivalent, it is difficult to make water soluble by neutralization, while if it exceeds 4.0 equivalent, the breaking strength of the coating film is deteriorated and lubricity tends to be impaired. Become.

Copolymer (b) In the present invention, as the acrylic resin, in addition to the copolymer (a), at least one or more of maleic acid, fumaric acid, itaconic acid and their monoalkyl esters (hereinafter referred to as maleic acid) (May be abbreviated as an acid or the like) and styrene (b). The monoalkyl ester is preferably based on an alcohol having 1 to 4 carbon atoms. Thereby, a high degree of alkali film-removing property is achieved.
This is because the carboxyl group of the copolymer (b) functions as a residual site of a base contained as a neutralizing agent. The molar ratio of styrene to maleic acid or the like is 75: 2
It is preferably from 5 to 1:99. If the styrene content is less than 1 mol%, the breaking strength of the organic resin coating film is reduced, so that the press formability, particularly the press formability (powdering resistance) when the temperature of the mold rises, is deteriorated. On the other hand, 75 mol% of styrene
If it exceeds 3, the carboxyl group is remarkably reduced, and the alkali film-removing property deteriorates. More preferred copolymer (b) has a molar ratio of styrene to maleic acid or the like of 75:25 to 20:
80.

The copolymer (b) is preferably adjusted so as to have at least one carboxyl group such as maleic acid in one molecule in order to ensure good alkali film-removing properties. Therefore, when producing the copolymer (b) by solution polymerization or the like, esterification is performed with an alcohol having a molar equivalent less than the molar equivalent of maleic acid or the like. The molecular weight is 500 to 10 as a weight average molecular weight.
000 is preferred. When the molecular weight is less than 500, the breaking strength of the organic resin coating film is remarkably reduced, which has an adverse effect on press moldability.
This is because the effect of improving the alkali film removal property cannot be expected. More preferred copolymer (b) has an average of 1 to 7 carboxyl groups remaining in one molecule and a weight average molecular weight of 50.
It is the case of 0-1000.

The copolymer (b) can be obtained by known solution polymerization, bulk polymerization, emulsion polymerization, or gas phase polymerization in a water-soluble solvent. In the case of solution polymerization, a known method, that is, in a water-soluble solvent such as butyl cellosolve heated to 80 to 140 ° C., under a nitrogen atmosphere, using a polymerization initiator,
A method is exemplified in which styrene and maleic acid are polymerized for 4 to 5 hours, and then heated and stirred at the same temperature for 2 to 3 hours. In the case of gas-phase polymerization, a polymerization component is introduced in a gas phase into a high-pressure resistant reaction vessel heated to 100 to 300 ° C., and polymerized in the presence or absence of a polymerization catalyst to obtain a copolymer having a relatively low molecular weight. An example of a method for producing the union is illustrated.

The copolymer (b) is preferably neutralized with ammonia and made water-soluble. The amount of ammonia added is 0.1 to 1 equivalent of the acid in the resin solid content of the copolymer (b).
A range of 6 to 4 equivalents is desirable. If the added amount of ammonia is less than 0.6 equivalent, the paint stability decreases, and if it exceeds 4 equivalents, the breaking strength of the organic resin coating film decreases, and the press formability decreases. The amount of added ammonia is 0.8 ~
More preferably, it is 2.5 equivalents.

Polymerization of a polymerizable compound having an ether bond
Body (c) In the present invention, in addition to the copolymers (a) and (b),
The polymer (c) of a polymerizable compound having an ether bond is contained to impart a higher alkali film-removing property. The copolymers (a) and (b) have a tendency that neutralization is broken and carboxyl groups tend to increase due to baking of the coating film and subsequent standing, and accordingly, alkali film-removing properties decrease. Unlike the copolymers (a) and (b), the polymer (c) of the polymerizable compound having an ether bond can maintain water solubility regardless of neutralization or non-neutralization. It is possible to prevent the polymers (a) and (b) from being decarboxylated due to carboxylation. The polymer (c) of the polymerizable compound having an ether bond is mixed with the copolymers (a) and (b) to form a composition.

Unlike the copolymers (a) and (b), the polymer (c) of the polymerizable compound having an ether bond has good compatibility with water even if it is not neutralized with a base. The coating composition containing the polymer (c) is effective for alkali film removal. As the polymerizable compound having an ether bond, an unsaturated carboxylic acid ester having the following structural formula is typical, and a polyalkylene (C2 to C3) glycol monoalkyl (C2) of an ethylenically unsaturated carboxylic acid is used. 1-3) It is preferably an ester of ether.

[0038]

Embedded image

Examples of the ethylenically unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid and the like. To this, 1 to 20 moles of an alkylene (2 or more carbon atoms) oxide is added, and the terminal is an alkyl (1 to 3 carbon atoms) ether. The polymerization degree (m) of the polyalkylene glycol is preferably from 1 to 20. If the degree of polymerization exceeds 20, the rust-preventive properties deteriorate.

The polymer (c), which is a polymerizable compound having an ether bond, coexists with the copolymers (a) and (b), and exhibits a suitable effect by constituting a composition. In the polymer (c) of the polymerizable compound having an ether bond, the terminal group of the ester of the polyalkylene glycol ether is generally a hydroxyl group. Components may cause a dehydration reaction, resulting in three-dimensional formation and gelation. On the other hand, the terminal hydroxyl group is converted to an alcohol (an alkyl alcohol such as methyl alcohol or ethyl alcohol).
, Or by esterification with an alicyclic carboxylic acid, it is possible to ensure paint stability during long-term storage.

The copolymer (a), the copolymer (b) and the polymer (c) of the polymerizable compound having an ether bond are each represented by a solid resin content of 100% by weight. The copolymer (a) is 90 to 40% by weight, preferably 8% by weight.
The copolymer (b) is 5 to 40% by weight, preferably 10 to 35% by weight, and the polymer (c) of the polymerizable compound having an ether bond is 5 to 20% by weight. %, Preferably 5 to 15% by weight.
When the amount of the copolymer (a) exceeds 90% by weight, the alkali film-removing property tends to decrease, and when the amount is less than 40% by weight, the rust-proofing property tends to decrease. When the amount of the copolymer (b) is less than 5% by weight, the alkali film-removing property tends to decrease. Further, when the amount of the polymer (c) of the polymerizable compound having an ether bond is less than 5% by weight, sufficient alkali film-removing property cannot be obtained. Tend.

The coating composition of the present invention is prepared, for example, as follows. The copolymer (a), the copolymer (b) and the polymer (c) of the polymerizable compound having an ether bond are
It is dispersed in a predetermined amount of water, heated to 60 to 70 ° C, and neutralized by adding a predetermined amount of ammonia. Further, for example, triethanolamine equivalent to 0.25 equivalent to 1 equivalent of the copolymer (a) is added to neutralize. If necessary, in addition to a solid lubricant, wax, fatty acid such as lauric acid or phosphoric acid or metal soap, a phosphorus-based organic substance as an anti-settling agent described later is added.

In the present invention, it is sufficient if the copolymer (a), the copolymer (b) and the polymer (c) of the polymerizable compound having an ether bond are simply mixed to form a composition. However, while maintaining the above composition ratio, the copolymer (a)
And a polymerizable compound having an ether bond are copolymerized to obtain an integrated copolymer (d), which is obtained by copolymerizing the copolymer (a) with a polymer of the polymerizable compound having an ether bond ( It can be used instead of c). Further, the component constituting the copolymer (a) and the component constituting the copolymer (b) are copolymerized to obtain an integrated copolymer (e). It can be used in place of the copolymer (b).

Further, a polymerizable compound having an ether bond is copolymerized with a component constituting the copolymer (b) or a component constituting the copolymer (a) and the copolymer (b), and each of them is integrally formed. To obtain copolymerized copolymer (f) or copolymer (g), which are replaced with copolymer (b) or polymer (c) of a polymerizable compound having an ether bond, respectively, or It can be used in place of the combination (a), the copolymer (b) and the polymer (c) of a polymerizable compound having an ether bond. By copolymerizing a polymerizable compound having an ether bond, low molecular weight components in the coating composition are reduced, and press moldability is further improved.

Here, the copolymer (b) is more highly admixed with the other constituents or with the constituents of the polymer than with the other constituents or the constituents of the polymer, rather than being copolymerized and integrated. It is possible to achieve an excellent alkali film removal property. Therefore, by further mixing the copolymer (b) with a copolymer or a mixture obtained from the components constituting the copolymer (a), the copolymer (b), and the polymer (c), the alkali removal is performed. The film properties are further improved.

A copolymer of a component constituting the copolymer (a) and a polymerizable compound having an ether bond, that is, a methacrylic acid ester composed of methacrylic acid and an alcohol having 2 or more carbon atoms, styrene and a carboxyl group A coating composition comprising a mixture of a copolymer (d) of a monomer having a monomer and a polymerizable compound having an ether bond and a copolymer (b) is produced, for example, by the following method.

In the case of solution polymerization, for example, 23 parts of styrene, 24 parts of butyl methacrylate, 23 parts of methacrylic acid and 23 parts of methacrylic acid are added to a water-soluble solvent (such as butyl cellosolve) adjusted to 80 to 140 ° C. under a nitrogen atmosphere. After adding 10 parts of polyethylene glycol monomethyl ether ester and preliminarily mixing, it is copolymerized with the polymerization initiator dropwise over 4 to 5 hours, and further copolymerized (b) (for example, 10 parts of styrene and methyl maleate half). 20 parts) (obtained by polymerization of 10 parts of ester)
It is manufactured by heating and stirring for ~ 8 hours.

The obtained coating composition was extracted with chloroform and filtered through a filter having a pore size of 0.45 μm.
Was measured. The spectrum had two peaks, and it was confirmed that this was a mixture of two peaks. In this case, the ratio of the components constituting the copolymer (a): the components constituting the copolymer (b): the components constituting the polymer (c) is 70: 2.
0:10. Thereafter, the coating composition is cooled to 55 to 60 ° C., and 0.5 to 4 equivalents of ammonia or 0.1 to 0.5 equivalent of a high boiling amine or hydroxide is added to 1 equivalent of the acid contained in the copolymer. An equivalent amount was added, and the mixture was neutralized and made water-soluble.

The coating composition of the present invention comprises a copolymer (a)
When a mixture of the copolymer (b) and the polymer (c) of the polymerizable compound having an ether bond is used, the acid value is determined by the acid value of each of the copolymers (a) and (b) before neutralization. ,
It is the sum of the acid values obtained by multiplying those composition ratios. Further, the coating composition of the present invention is obtained by copolymerizing a component constituting the copolymer (a) and a polymerizable compound having an ether bond,
When a mixture of the copolymer (d) and the copolymer (b) is integrated, the acid value is the acid value of each of the copolymer (d) and the copolymer (b) before neutralization, It is the sum of the acid values obtained by multiplying those composition ratios.

Further, the coating composition of the present invention is obtained by copolymerizing the component constituting the copolymer (a) and the component constituting the copolymer (b) to obtain an integrated copolymer (e). When a mixture of the polymer (c) of the polymerizable compound having an ether bond is used, the acid value is the acid value of the copolymer (e) before neutralization. Further, the coating composition of the present invention is obtained by copolymerizing a component constituting the copolymer (b) and a polymerizable compound having an ether bond to form an integrated copolymer (f) and copolymer (a). When it is composed of a mixture, the acid value is the sum of the acid values obtained by multiplying the respective acid values of the copolymer (f) and the copolymer (a) before neutralization by their composition ratio. Furthermore, the coating composition of the present invention is obtained by copolymerizing a component constituting the copolymer (a), a component constituting the copolymer (b), and a polymerizable compound having an ether bond to form an integrated copolymer. When it is a polymer (g), the acid value is the acid value of the copolymer (g) before neutralization.

The acid value of the coating composition is from 20 to 300 mg-
It is preferably adjusted to be KOH / g. More preferably, it is 25 to 250 mg-KOH / g, and more preferably 100 to 230 mg-KOH / g. For example, when the acid value of the copolymer (g) is less than 20 mg-KOH / g, the alkali film-removing property is extremely reduced. In addition, it becomes difficult to form a paint by making the copolymer (g) itself water-soluble. Conversely, when the acid value of the copolymer (g) exceeds 300 mg-KOH / g, the rust-preventing property is extremely reduced, and the effects of styrene and other rust-preventing agents added are not exhibited.

The weight average molecular weight of the coating composition was 10,000.
It is preferably from 0 to 70,000, and from 10,000 to
More preferably, it is 50,000. If it is less than 10,000, press formability deteriorates, and if it exceeds 70,000, the viscosity of the coating composition tends to increase, and coating tends to be difficult. The glass transition point Tg of the coating composition is preferably 0 ° C. or higher. When the temperature is lower than 0 ° C., heat generated during press molding causes the coating formed by applying the coating composition to the surface of the metal plate to be detached or melted from the metal plate, thereby lowering the lubricating performance of the coating. It is. Preferred Tg is 30-
100 ° C.

Preferred Additives It is preferable that a lubricant, a rust preventive, a colorant, and the like are added to the acrylic resin for the purpose of further improving rust prevention and press moldability. Preferred rust inhibitors include:
Metal soaps, which are salts of higher fatty acids such as lauric acid, palmitic acid, stearic acid and oleic acid with alkaline earth metals such as calcium and barium; and zinc, calcium or ammonium salts of phosphoric acid and molybdic acid. The preferred amount of the rust inhibitor is 3 to 30% by weight, preferably 5 to 20% by weight, based on the total resin solid content of the coating composition. Within this range, the rust resistance is excellent without extremely impairing the stability of the paint.

The coating composition may further contain a solid lubricant or wax as a lubricant. Examples of the solid lubricant include graphite, molybdenum disulfide, talc, a fluorine-containing resin, boron nitride, and carbonate. Calcium, melamine, isocyanuric acid adducts and the like can be mentioned. Waxes include polyethylene wax, petroleum paraffin wax, animal and vegetable oils and fats, higher fatty acids, higher alcohols, esters of higher fatty acids and higher alcohols, higher fatty acid amides, amine salts of higher fatty acids, and the like, in order to solidify the lubricant film. It is preferable to use those having a melting point of 45 ° C. or higher. To increase the melting point, there is a method of eliminating double bonds by hydrogenation. The preferable addition amount of the lubricant is 3 to 50% by weight, preferably 5 to 30% by weight based on the total resin solid content of the coating composition. Within this range, the alkali film-removing property is not impaired, the press formability is excellent, the stability of the coating material is not extremely impaired, and the rust prevention is also excellent.

In particular, when a metal soap or a zinc, calcium or ammonium salt of phosphoric acid and molybdic acid is used as an additive, their specific gravities are larger than those of a solvent, so that they tend to precipitate. Therefore, it is preferable to blend the following alkyl phosphonic acid monoalkyl ester (phosphorus organic substance A) and alkyl phosphonic acid dialkyl ester (phosphorus organic substance B) which also function as an anti-settling agent. For example, the phosphorus-based organic substance is preferably in a weight ratio of 1:99 to 20: 8 with respect to the total resin solid content of the coating composition.
0, more preferably from 5:95 to 15:85. If the content of the phosphorus-based organic substance is less than 1% by weight, the effect of preventing sedimentation is not exhibited, and if it exceeds 20% by weight, the cohesive strength of the coating film is reduced, and the coating film is peeled off during processing, so-called powdering is likely to occur.

When phosphorus-based organic substances are used in a mixture, the weight ratio of phosphorus-based organic substance A (monoalkyl alkylphosphonic acid ester) to phosphorus-based organic substance B (dialkyl alkylphosphonic acid ester) is 10:90 to 90:10. If there is, the effect is remarkable. 10% by weight of phosphorus organic substance A
When the amount is less than 90%, the paint stability is remarkably deteriorated. When the amount exceeds 90% by weight, the amount of hydroxyl groups adsorbed on the surface of the steel sheet is increased, so that the alkali film removing property is deteriorated.

[0057]

Embedded image

Here, R ₁ is a saturated hydrocarbon group or an unsaturated hydrocarbon group having 10 to 50 carbon atoms, which may be linear or branched, and specifically, α 1 having 40 carbon atoms.
-Olefins are exemplified. R ₂ is a saturated or unsaturated hydrocarbon group having 1 to 8 carbon atoms,
₃ , C ₃ H ₇ , C ₅ H ₁₁ and C ₈ H ₁₇ , and are preferably α-olefins having 5 or 8 carbon atoms. When there are two R _{2 s} , they may be the same or different.

The coating composition may contain, in addition to the above components, solvents such as hydrocarbons, coloring agents, pigments, dyes and the like. An additive that is added to the coating composition of (1) can also be added.

When the coating composition is applied to a metal plate such as a hot-rolled steel plate, a cold-rolled steel plate, a stainless steel plate, various surface-treated steel plates, and an aluminum plate, the amount of adhesion is 0.5 to 5 g / dry weight per one side. m ² is preferable. 0.
If it is less than 5 g / m ^2, the unevenness on the surface of the metal plate cannot be filled, and the effects of the present invention on press formability and rust prevention cannot be exhibited. If it exceeds 5 g / m ² , powdering occurs during press molding. A more preferred range is 0.5 to 3 g / m ^2.

The coating can be carried out by a known method such as roll coating, spray coating, dip coating, brush coating and the like. Drying conditions are a temperature of 40 ° C to 200 ° C and a drying time of about 1 to 90 seconds. In addition, the metal plate in the present invention includes a metal band that is a band-shaped metal plate, and is not particularly limited, but a hot-dip galvanized steel sheet, an alloyed hot-dip galvanized steel sheet,
Hot rolled steel sheet, cold rolled steel sheet, galvanized steel sheet, electric Zn-
Examples include a Ni-plated steel plate, an aluminum plate, and a stainless steel plate.

[0062]

The present invention will be described more specifically below with reference to examples and comparative examples. <Test piece preparation method> On the surface of the following seven types of metal plates A to G degreased by alkali washing, the following thirteen types of acrylic resins A to M, and the following seven types of neutralizers A to G and The coating composition shown in Table 1 prepared by adding the following additives was applied to both sides such that the dry coating weight was 1.5 g / m ² per side, and the ultimate plate temperature after 10 seconds was reached. It dried so that it might become 60 degreeC using the hot-air dryer. Thereafter, rust-preventive oil (16.0 cSt / 40 ° C.) was further applied to both surfaces in an amount of 0.5 to 1.
The test piece was applied so as to be 0 g / m ² .

Metal sheet: A: alloyed hot-dip galvanized steel sheet B: hot-rolled steel sheet C: cold-rolled steel sheet D: stainless steel sheet E: aluminum sheet F: electro-galvanized steel sheet G: hot-dip galvanized steel sheet

Acrylic resin: A: Mixture of (a), (b), (c) Copolymer (a): n-butyl methacrylate-styrene-methacrylic acid copolymer (b): Styrene-itaconic acid copolymer Polymer (c): Esterified polymer of methacrylic acid and polyethylene glycol monomethyl ether

B: a mixture of (a), (b) and (c) Copolymer (a): n-butyl methacrylate-styrene-acrylic acid copolymer (b): styrene-maleic acid Copolymer Polymer (c): Polymer of methacrylic acid and polyethylene glycol ester

C: A mixture of (b) and (d) Copolymer (b): Styrene-methyl maleate half ester copolymer Copolymer (d): Methacrylic acid-n-butyl-styrene-acrylic acid Esterified product obtained from polyethylene glycol monomethyl ether-methacrylic acid copolymer

D: Mixture of (b) and (d) Copolymer (b): Styrene-itaconic acid copolymer Copolymer (d): From methacrylic acid-n-butyl-styrene-acrylic acid and polyethylene glycol Obtained ester-methacrylic acid copolymer

E: Mixture of (b) and (d) Copolymer (b): Styrene-ethyl maleate half ester copolymer Copolymer (d): Ethyl methacrylate-styrene-acrylic acid and polyethylene glycol mono Ester-acrylic acid copolymer obtained from propyl ether

F: Mixture of (b) and (d) Copolymer (b): Styrene-itaconic acid copolymer Copolymer (d): Ester obtained from isopropyl methacrylate-styrene-acrylic acid and polyethylene glycol -Acrylic acid copolymer

G: Mixture of (c) and (e) Polymer (c): Polymer of esterified product obtained from methacrylic acid and polyethylene glycol monomethyl ether Copolymer (e): n-butyl styrene methacrylate -Methacrylic acid-maleic acid copolymer

H: A mixture of (c) and (e) Polymer (c): Esterified polymer obtained from methacrylic acid and polyethylene glycol monomethyl ether Copolymer (e): n-butyl styrene methacrylate Acrylic acid-maleic acid copolymer

I: a mixture of (c) and (e) Polymer (c): a polymer of an esterified product obtained from methacrylic acid and polyethylene glycol monomethyl ether Copolymer (e): n-butyl styrene methacrylate -Methacrylic-itaconic acid copolymer

J: mixture of (a) and (f) Copolymer (a): n-butyl methacrylate-styrene-acrylic acid copolymer Copolymer (f): maleic acid-styrene-methacrylic acid Esterified copolymer obtained from polyethylene glycol monomethyl ether

K: (g) homopolymer (g): ester-methacrylic acid-maleic acid copolymer obtained from n-butyl methacrylate-styrene-methacrylic acid and polyethylene glycol monomethyl ether

L: (g) homopolymer (g): ester-acrylic acid-maleic acid copolymer obtained from n-butyl methacrylate-styrene-methacrylic acid and polyethylene glycol

M: mixture of (g) and (b) Copolymer (g): esterified product obtained from methacrylic acid-n-butyl-styrene-methacrylic acid and polyethylene glycol monomethyl ether-methacrylic acid-maleic acid copolymer Copolymer (b): Styrene-maleic acid copolymer

Additives (% by weight based on the total resin solid content of the coating composition) Calcium stearate 5% Zinc phosphate 5% Polyethylene wax 10% Phosphorus organic substance A: R ₁ in the formula is α-olefin having 40 carbon atoms Phosphorus Organic substance B: wherein R ₂ is an α-olefin having 5 carbon atoms

Neutralizer A: Ammonia (boiling point −33 ° C.) B: Isopropylamine (boiling point 32 ° C.) C: Diethylamine (boiling point 56 ° C.) D: N, N-dimethylethanolamine (boiling point 130)
C) E: Monoethanolamine (boiling point 170 ° C) F: Triisopropanolamine (boiling point 305 ° C) G: Triethanolamine (boiling point 360 ° C)

The test pieces thus obtained were examined for press formability, rust prevention, alkali film removal, chemical conversion treatment, blocking resistance, coating film drying property, and paint stability. Table 2 shows the results. In addition, the evaluation of each characteristic of the test piece was performed as follows. <Evaluation method> (1) Press formability Room temperature press formability (limit wrinkle holding load, galling resistance, powdering resistance) Using an Erichsen cup drawing tester, under the following pressing conditions and at a mold temperature of room temperature: (25 ° C.), a cylindrical deep drawing was performed to obtain a test piece. Punch diameter 33mmφ (Cylinder, cylinder with beads) Drawing die shoulder curvature 2mmR Blank diameter cylinder 68mmφ, cylinder with beads 68mmφ Limit wrinkle holding load Evaluated by the maximum t number that can be formed without breaking

(Criteria for Evaluation of Mold Galling Resistance) The side walls of the test pieces were observed, and the presence or absence of mold galling was evaluated in four steps. ◎ = No mold seizure 〇 = Slight mold seizure △ = Slightly large seizure × = Many seizure

(Evaluation Criteria for Powdering Resistance) The sidewalls of the test pieces were observed, and the presence or absence of powdering was evaluated on a four-point scale. ◎ = No powdering occurred 〇 = Some powdering occurred △ = Somewhat powdering occurred × = Many powdering occurred

Warm press formability (critical wrinkle holding load, galling resistance, powdering resistance) Using an Erichsen cup drawing tester, under the following pressing conditions and keeping the mold temperature at 80 ° C, the cylindrical depth Draw-forming was performed to obtain a test piece. Punch diameter 33mmφ (cylinder) Draw die shoulder curvature 2mmR Blank diameter cylinder 68mmφ Draw speed 60mm / sec Limit wrinkle holding load Evaluated by the maximum t number that can be formed without breaking

(Evaluation Criteria for Galling Resistance) The sidewalls of the test pieces were observed, and the presence or absence of mold galling was evaluated on a four-point scale. ◎ = No mold seizure 〇 = Slight mold seizure △ = Slightly large seizure × = Many seizure

(Evaluation Criteria for Powdering Resistance) The side walls of the test pieces were observed, and the presence or absence of powdering was evaluated on a four-point scale. ◎ = No powdering occurred 〇 = Some powdering occurred △ = Somewhat powdering occurred × = Many powdering occurred

(2) Rust-preventive property A rust-preventive oil (non-last^RZ5: Idemitsu Kosan
2 g / m ^TwoApply oil to JIS Z2371
According to the above, spray a salt solution having a concentration of 3% by weight, and after 17 hours,
White rust occurrence status (red rust for cold rolled steel sheet and hot rolled steel sheet)
It evaluated as area ratio.

(3) Alkali delaminating property An alkaline cleaning liquid (degreaser: Fine Cleaner 4460: manufactured by Nippon Parkerizing Co., Ltd.) adjusted to a concentration of 3% by weight and a liquid temperature of 40 ° C. was sprayed onto a test piece at a spray pressure of 1 kg / cm. ^Two
Degreased by spraying for 10 seconds, the degreased test piece was immersed in water, and the water-wetted area after pulling up was visually observed, and the alkali delamination property was evaluated in three steps based on the following criteria. 〇 = Wet site: 100% of the surface area of the metal plate △ = Water site: 95% or more of the surface area of the metal plate × = Water site: Less than 95% of the surface area of the metal plate

(4) Chemical conversion treatment A test piece was sprayed with an alkali washing liquid (degreaser: Fine Cleaner-4460: manufactured by Nippon Parkerizing Co., Ltd.) adjusted to a concentration of 3% by weight and a liquid temperature of 40 ° C. at a spray pressure of 1 kg. / Cm ²
And then degreased by spraying for 30 seconds, then immersed in a chemical conversion solution (PB-L3020M: manufactured by Nippon Parkerizing Co., Ltd.) adjusted to 43 ° C. for 120 seconds to perform a chemical conversion treatment, and then using a scanning electron microscope (× 1000). The crystal morphology of the chemical conversion treatment film was observed. Each metal plate coated with a coating composition other than the coating composition of the present invention was subjected to a chemical conversion treatment under the same conditions as a chemical conversion coating film. 〇 = A good chemical conversion coating that is no different from a chemical conversion coating on an unpainted steel sheet. △ = A chemical conversion coating with a slight reduction in crystal size and coarseness compared to a chemical conversion coating on an unpainted steel sheet. Generates almost no

(5) Blocking Resistance Two test pieces superposed with the coating surfaces facing each other
While being tightened with a torque of 0 kg · cm, it was left in a thermostat at 60 ° C. for 6 hours. Thereafter, the stacked test pieces were peeled off, and the blocking resistance was evaluated on a four-point scale according to the adhesion state at the time of peeling off. ◎ = No stickiness 〇 = Some sticky △ = Stuck × = Large sticky

(6) Drying of Coating Film The coating film of the present invention was immediately applied and baked, and the coating film was checked for stickiness by finger touch, and at the same time, the coating films immediately after coating and baking were overlapped with the coating surfaces inside. The two test pieces were allowed to stand at room temperature for 6 hours while being tightened with a torque of 300 kg · cm. Thereafter, the peeling state and the appearance change when the torque was released were evaluated in four steps. ◎ = No stickiness / peeled off by its own weight when releasing the torque of stacked test pieces, no change in appearance ○ = No sticky / peeling off by its own weight when releasing the torque of stacked test pieces, appearance changed △ = Slightly sticky・ Does not peel by its own weight when releasing the torque of stacked test pieces. × = There is stickiness. ・ Does not peel by its own weight when releasing the torque of stacked test pieces.

(7) Paint stability The paint composition of the present invention, which was placed in a 200 ml measuring cylinder in an oven at 50 ° C., was left for one month. The viscosity was measured, compared with the viscosity before standing, and evaluated on a 4-point scale. The solid content in the coating composition was 20% by weight. ＝= No separation of the coating composition and no change in viscosity. ＝= No separation of the coating composition, but there was a tendency to increase the viscosity. Notable occurrence and viscosity increase

[0091]

[Table 1]

[0092]

[Table 2]

[0093]

[Table 3]

[0094]

[Table 4]

[0095]

[Table 5]

[0096]

[Table 6]

[0097]

[Table 7]

[0098]

[Table 8]

[0099]

[Table 9]

[0100]

[Table 10]

[0101]

[Table 11]

[0102]

[Table 12]

[0103]

The lubricated metal sheet having a coating composition formed by applying the coating composition of the present invention and the coating composition of the present invention to the surface thereof has an alkali film-removing property, a chemical conversion property, a rustproof property, It is excellent in film drying property, blocking resistance and paint stability, and has remarkably improved press formability including mold galling resistance and powdering resistance. INDUSTRIAL APPLICABILITY According to the present invention, difficult-to-form press molding, which has conventionally been a problem, becomes possible, and is suitably used as a material for automobile parts and the like.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Ogata 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Inside the Technical Research Institute of Kawasaki Steel Corporation (72) Inventor Shigeru Umino 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Kawasaki 4F100 AB01A AB03 AB04 AB10 AK09 AK09J AK12 AK12B AK12J AK24B AK25 AK25B AK25J AK54B AL01 AL01B AL05B BA02 CA30B CC00B GB32. CJ131 GA06 MA14 NA03 NA23 PB06 PC02

Claims (6)

[Claims] 1. A coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin is a monomer having methacrylic acid ester composed of methacrylic acid and an alcohol having 2 or more carbon atoms, styrene and a carboxyl group. Selected from maleic acid, fumaric acid, itaconic acid and their monoalkyl esters
A coating composition comprising a copolymer (b) of at least one species and styrene and a polymer (c) of a polymerizable compound having an ether bond. 2. A coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin has methacrylic acid ester composed of methacrylic acid and an alcohol having 2 or more carbon atoms, styrene, and a polymerizable polymer having an ether bond. A copolymer of a compound and a monomer having a carboxyl group (d) and a copolymer of styrene with one or more selected from maleic acid, fumaric acid, itaconic acid and monoalkyl esters thereof (b) A) a coating composition comprising: 3. A coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin is a monomer having methacrylic acid ester composed of methacrylic acid and an alcohol having 2 or more carbon atoms, styrene, and a carboxyl group. And a copolymer (e) with one or more selected from maleic acid, fumaric acid, itaconic acid and monoalkyl esters thereof, and a polymer (c) of a polymerizable compound having an ether bond. A coating composition, characterized in that: 4. A coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin has a methacrylic acid ester composed of methacrylic acid and an alcohol having 2 or more carbon atoms, styrene, and a monomer having a carboxyl group. Copolymer (a) with at least one selected from maleic acid, fumaric acid, itaconic acid and monoalkyl esters thereof, styrene, and a polymerizable compound having an ether bond (f) A) a coating composition comprising: 5. A coating composition containing an acrylic resin and a neutralizing agent, wherein the acrylic resin has a methacrylic acid ester comprising methacrylic acid and an alcohol having 2 or more carbon atoms, styrene, and a polymerizable polymer having an ether bond. A coating composition comprising a compound, a monomer having a carboxyl group, and a copolymer (g) of at least one selected from maleic acid, fumaric acid, itaconic acid and monoalkyl esters thereof. object. 6. A lubricated metal sheet having a coating film formed by applying the coating composition according to claim 1 on the surface thereof.