WO2019065939A1 - Aqueous anticorrosive coating composition, anticorrosive coating film, substrate with anticorrosive coating film, and method for producing substrate with anticorrosive coating film - Google Patents

Abstract

The present invention relates to an aqueous anticorrosive coating composition, an anticorrosive coating film, a substrate with an anticorrosive coating film, and a method for producing a substrate with an anticorrosive coating film, wherein the aqueous anticorrosive coating composition contains: an aqueous resin (A) having one or more carboxy groups in one molecule; and an aqueous epoxy resin (B) other than the aqueous resin (A).

Description

Aqueous anticorrosion coating composition, anticorrosion film, anticorrosion film-coated substrate and method for producing anticorrosion film-coated substrate

The present invention relates to an aqueous anticorrosive coating composition, an anticorrosive coating, a substrate with an anticorrosive coating, and a method for producing a substrate with an anticorrosive coating.

Various industrial fields, such as bridges, tanks, plants, (land) structures such as containers (for transport), etc., are usually coated with anticorrosion coatings to prevent corrosion. In recent years, from the viewpoint of environmental protection, safety of working environment, etc., as a composition which forms this antirust coating film, switching from a solvent paint to an aqueous paint (aqueous anticorrosion paint composition) is desired.

As the water-based anti-corrosive paint composition, paint compositions such as alkyd resin systems, epoxy ester resin systems, and epoxy-amine curing systems in which an epoxy resin and an amine curing agent are reacted are known.
In addition, in Patent Document 1, corrosion resistance and water resistance can be obtained by using an aqueous resin dispersion obtained by emulsion polymerization of a monomer mixture containing a fatty acid-modified unsaturated monomer and another polymerizable unsaturated monomer copolymerizable with the monomer. It is disclosed that it is possible to form a coating film excellent in Patent Document 2 discloses a composition in which a modified epoxy ester obtained by reacting an epoxy resin with an unsaturated fatty acid and further reacting an ethylenically unsaturated monomer containing an unsaturated carboxylic acid with a (semi) drying oil is used. It is disclosed that a coating film having excellent corrosion resistance and water resistance can be formed by using a substance.

WO 2004/074327 JP 2003-64302 A

In order that the coating film formed from the conventional aqueous | water-based anticorrosion paint compositions, such as the said alkyd resin type | system | group and an epoxy ester resin type | system | group, and the composition described in the said patent document 1 and 2, hardens by oxidation polymerization reaction, It took time to exhibit sufficient coating film performance. In addition, when forming a primer coating film from these compositions and applying a top coating composition over it to form a top coating film, lifting may occur unless the coating is repeated at an appropriate interval. . Furthermore, the coating film formed from these compositions needed further improvement in the use environment where mechanical properties such as high corrosion resistance, water resistance and impact resistance are required.
In addition, a coating film formed from the above-mentioned epoxy-amine-curable aqueous anti-corrosive coating composition has a high shrinkage stress due to a crosslinking reaction, and has excellent corrosion resistance and water resistance to a substrate, and It was difficult to make a coating film having sufficient adhesion.

Nonferrous metals and stainless steel are used as the materials of the above-mentioned structures, in particular, transportation containers such as frozen / refrigerated containers. The oxide film is formed on the surface of these materials, so the surface activity is low, and it is difficult to firmly attach an anticorrosive coating film formed using a conventional aqueous anticorrosion paint composition to these surfaces It turned out that it was.
In addition, impact resistance is also calculated | required by the antirust coating film formed in the said structure, especially the container for transport.

One embodiment of the present invention is an aqueous anticorrosion paint composition having excellent dryability which can be cured at ordinary temperature (5 to 35 ° C.), and also has excellent corrosion resistance and water resistance, as well as a substrate, particularly nonferrous metal. Disclosed is an aqueous anticorrosion paint composition capable of forming a coating film having excellent adhesion and impact resistance to substrates and stainless steel substrates.

As a result of earnestly examining about the method to solve the said subject, according to the coating composition of a specific composition, it discovers that the said subject can be solved and came to complete this invention.
The structural example of this invention is as follows.

<1> An aqueous anticorrosive coating composition comprising an aqueous resin (A) having one or more carboxy groups in one molecule, and an aqueous epoxy resin (B) other than the aqueous resin (A).

<2> The aqueous resin (A) according to <1>, which comprises one or more selected from an aqueous alkyd-modified acrylic resin (A1) having a carboxy group and an aqueous modified epoxy resin (A2) having a carboxy group. Aqueous anticorrosion paint composition.
The aqueous | water-based rustproofing coating composition as described in <2> whose <3> said alkyd modified acrylic resin (A1) and said modified epoxy resin (A2) are resin which has a bisphenol A structure.

<4> In any one of <1> to <3>, the aqueous epoxy resin (B) is contained in an amount of 1 to 30 parts by mass as a nonvolatile matter based on 100 parts by mass of the nonvolatile matter of the aqueous resin (A) The aqueous | water-based anticorrosion paint composition as described.

<5> Any one of <1> to <4>, which is a multicomponent type containing a first agent containing the aqueous resin (A) and a second agent containing the aqueous epoxy resin (B) The aqueous | water-based anticorrosion paint composition as described.

<6> The aqueous anticorrosive coating composition according to any one of <1> to <5>, further comprising a pigment (D).
The aqueous | water-based rustproof coating composition as described in <6> in which the <7> above-mentioned pigment (D) contains a rustproof pigment (D1).
<8> The aqueous anticorrosive coating composition according to <6> or <7>, wherein the pigment volume concentration (PVC) in the aqueous anticorrosive coating composition is 20 to 50%.

<9> An anticorrosive coating film formed from the aqueous anticorrosive coating composition according to any one of <1> to <8>.
<10> A substrate with a rust preventive coating film having the rust preventive coating film according to <9> and a substrate.
<11> The substrate with a rustproofing coating according to <10>, wherein the substrate is a non-ferrous metal or stainless steel.

The manufacturing method of the base material with a rust-proof coating film containing <12> following process [1] and [2].
[1] A step of applying the aqueous anticorrosion paint composition according to any one of <1> to <8> to a substrate [2] drying an aqueous anticorrosion paint composition coated on a substrate Process to form rustproof coating film

According to one embodiment of the present invention, it is an aqueous anticorrosion paint composition which is excellent in drying property which can be cured at room temperature, and which has excellent corrosion resistance and water resistance, as well as a base material such as steel and the like. It is possible to provide an aqueous anticorrosion coating composition capable of forming a coating film having excellent adhesion and impact resistance to non-ferrous metal substrates and stainless steel substrates.
In addition, the aqueous anticorrosion paint composition according to one embodiment of the present invention is also excellent in adhesion to the top coat film formed on the anticorrosion coating film obtained from the composition, and in particular, the corrosion resistance Regardless of the interval from the formation of the coating film to the formation of the top coating film, coating film defects such as lifting are less likely to occur, so that a desired laminated coating film can be easily formed.

An aqueous anticorrosive coating composition, an anticorrosive coating film, a substrate with an anticorrosive coating film, and a method for producing the same according to an embodiment of the present invention will be described below. However, the present invention is not limited by the following description.

«Water-based anticorrosion paint composition»
An aqueous anticorrosive coating composition according to an embodiment of the present invention (hereinafter simply referred to as "the present composition") is an aqueous resin (A) having one or more carboxy groups in one molecule (hereinafter referred to as "component ( The same applies to other components) and a composition containing an aqueous epoxy resin (B) other than the aqueous resin (A).
The composition is an aqueous anticorrosion paint composition excellent in cold-settable drying property, and according to the composition, it has excellent corrosion resistance and water resistance, and a substrate, particularly a nonferrous metal substrate A coating film having excellent adhesion and impact resistance can also be formed on stainless steel and stainless steel substrates.

In particular, the present composition is excellent even for substrates such as non-ferrous metal substrates and stainless steel substrates, for which it was difficult to form a coating having sufficient adhesion with conventional compositions. A coating film having adhesion and impact resistance can be formed. In addition, although the detailed action mechanism which this composition show | plays the said effect is not necessarily clear, the following is considered as the example.
The composition of the present invention can form a hydroxyl group and an ester bond by the crosslinking reaction of the carboxy group of the component (A) and the epoxy group of the component (B), and can be strongly bonded to the substrate surface. As a result, compared to conventional compositions such as alkyd resin systems, epoxy ester resin systems and epoxy-amine curing systems, it is excellent in adhesion to a substrate and a coating film excellent in impact resistance having toughness by a crosslinking reaction. Can be formed.

The present composition is suitable for the outer surface of a frozen / refrigerated container where materials such as non-ferrous metals (eg, aluminum, copper, brass, zinc plating, zinc spraying), stainless steel (eg, SUS304, SUS410) are often used. It is suitably used as a paint capable of forming a rustproof coating film having excellent adhesion and impact resistance to the substrate.

In the present invention, the "water-based anti-corrosive paint composition" refers to the dispersion and / or dissolution of components such as component (A) and component (B) in water or a medium (aqueous medium) containing water as a main component. It refers to the anticorrosion paint composition.

Further, in the present invention, the “aqueous resin” is a resin that uses water or water as a main solvent or dispersion medium, or a resin that can be mixed with water (dilutable with water), and more specifically, Examples thereof include water-dispersible resins, water-soluble resins and self-emulsifying resins. In addition, the resin which can be mixed with water (that can be diluted with water) means a resin which does not show a significant increase in viscosity when mixed with water.

Such aqueous resin can be obtained by any known method, for example, solution polymerization, suspension polymerization, emulsion polymerization, seed polymerization, miniemulsion polymerization, microemulsion polymerization, emulsifier-free (soap-free) emulsion polymerization And so on. In addition to these, the aqueous resin can also be obtained by a method of emulsifying the resin by a known method, for example, phase inversion emulsification, D phase emulsification, forced emulsification, gel emulsification, inversion emulsification, high pressure emulsification and the like.

Since the present composition uses the aqueous resin (A) and the aqueous epoxy resin (B), it becomes a coating composition excellent in ease of preparation, storage stability and the like.
In addition, if it is not the said "aqueous resin", and the resin and epoxy resin which have a carboxy group, and water are mixed, it exists in the tendency for it to become difficult to prepare a desired coating composition. For this reason, it is preferable to use the component containing water as said component (A) and (B), respectively.

The form of the present composition is preferably a multicomponent composition comprising a first agent and a second agent, in consideration of storage stability and ease of storage, and, for example, the composition containing the component (A) One agent, preferably a first agent containing the component (A) and water (C), more preferably a first agent containing the component (A), water (C) and a pigment (D), and A two-component composition comprising a second agent comprising component (B), preferably a second agent comprising said component (B) and water (C), is desirable. Furthermore, it can also be set as the composition of three or more types containing the 3rd agent etc. which contain the following other components etc.

Moreover, when this composition is a multi-component type composition containing a 1st agent and a 2nd agent, the formation method of a coating film by adjusting the usage-amount of the said component (A) and the said component (B) The crosslink density of the coating film formed can be easily adjusted according to the type of substrate, application, coating environment and the like. As a result, it is possible to easily adjust the balance between the toughness and the flexibility of the coating depending on the required performance.
Furthermore, when the composition is a multicomponent composition comprising a first agent containing the component (A) and the component (D), and a second agent containing the component (B), Since the said component (A) which has group has affinity with respect to a component (D), the improvement of the dispersibility of a component (D) is anticipated. As a result, improvement in production efficiency and the like resulting from the improvement in the dispersibility of the component (D) can be expected.

<Aqueous resin having a carboxy group (A)>
The component (A) is not particularly limited as long as it is an aqueous resin having one or more carboxy groups in one molecule.
The component (A) contained in the present composition may be one type, or two or more types.

The content of the non-volatile component of the component (A) with respect to the non-volatile component of 100% by mass of the present composition is well-balanced by the corrosion resistance, water resistance, adhesion to a substrate, particularly nonferrous metal substrate and stainless steel substrate and impact resistance. The amount is preferably 20 to 50% by mass, and more preferably 25 to 45% by mass, from the viewpoint of easily forming an excellent coating film.

Examples of the resin contained in the component (A) include an acrylic resin, an alkyd resin, an epoxy resin, a urethane resin, a polyester resin, a vinyl acetate resin, a phenoxy resin, and modified products thereof having a carboxy group. Examples of the modified products include acrylic modified products, alkyd modified products, epoxy modified products, amine modified products and urethane modified products. For example, alkyd modified acrylic resin, acrylic modified alkyd resin, acrylic modified epoxy resin, amine modified A modified epoxy resin such as an epoxy resin, an acrylic modified urethane resin, etc. may be mentioned. Here, the alkyd-modified acrylic resin refers to a resin in which the proportion of structural units constituting the acrylic resin exceeds 50% by mass with respect to 100% by mass of all structural units constituting the resin. That is, the said modified | denatured thing says thing of the resin whose ratio of the structural unit derived from the modified | denatured component is less than 50 mass%.
Among these, from the viewpoint of obtaining a composition which is more excellent in storage stability, a resin not having an epoxy group is preferable, and corrosion resistance, water resistance, adhesion to a substrate, particularly nonferrous metal substrate and stainless steel substrate And at least one of an alkyd-modified acrylic resin (A1) having a carboxy group and a modified epoxy resin (A2) having a carboxy group, which are described later, from the viewpoint of easily forming a coating excellent in a well-balanced manner by impact resistance. Is preferred.

The content of the resin in 100% by mass of the component (A) is preferably 30 to 75% by mass, and more preferably, from the viewpoint of being able to obtain a coating composition which is excellent in ease of preparation, storage stability, etc. It is 35 to 60% by mass.
Water is preferably contained in the residue of the component (A), and if necessary, conventionally known components such as surfactants may be contained.

<Alkyd-Modified Acrylic Resin Having a Carboxy Group (A1)>
The alkyd-modified acrylic resin (A1) having a carboxy group can be synthesized, for example, using a (meth) acrylic compound and an alkyd resin, and an unsaturated monomer containing a (meth) acrylic compound, an alkyd resin and an epoxy compound It is more preferable that it is resin synthesize | combined using and.
Specifically, a solvent is added to an alkyd resin, an epoxy compound and a catalyst such as triphenylphosphine are added to this, and the mixture is allowed to react at 70 to 170 ° C. for about 3 to 15 hours. It can be synthesized by adding predetermined amounts of a saturated monomer and a polymerization initiator and reacting at 80 to 150 ° C. for about 3 to 10 hours.

In addition, in order to obtain resin (A1) which has a carboxy group, the compound which has a carboxy group may be used as an unsaturated monomer, for example, you may use the compound which has a carboxy group as an alkyd resin, and carboxy as an epoxy compound A compound having a group may be used, or a carboxy group may be generated when reacting these, or after reacting these, modification such as when the resin finally obtained has a carboxy group You may go.

The alkyd resin can be obtained by a conventionally known method, and comprises (semi) drying oil, (semi) drying oil fatty acid or unsaturated fatty acid excluding the above unsaturated monomer, an acid component, and a polyhydric alcohol component It is preferable that it is resin obtained by making it polycondensate, and you may use an epoxy compound as needed.

Examples of the (semi) drying oil include fish oil, dehydrated castor oil, safflower oil, linseed oil, soybean oil, sesame oil, poppy seed oil, poppy seed oil, hemp seed oil, grape kernel oil, corn oil, tall oil, sunflower oil And cottonseed oil, walnut oil and rubber seed oil, and examples of (semi) drying oil fatty acids include fish oil fatty acid, dehydrated castor oil fatty acid, safflower oil fatty acid, linseed oil fatty acid, soybean oil fatty acid, sesame oil fatty acid, poppy seed oil Fatty acid, eno oil fatty acid, hemp seed oil fatty acid, grape kernel oil fatty acid, corn oil fatty acid, tall oil fatty acid, sunflower oil fatty acid, cottonseed oil fatty acid, walnut oil fatty acid, rubber seed oil fatty acid As fatty acids, for example, palmitoleic acid, oleic acid, vacenic acid, linoleic acid, linolenic acid, stearidonic acid, eicosapentaene And the like. These may be used alone or in combination of two or more.

The amount of the (semi) drying oil, the (semi) drying oil fatty acid, and the unsaturated fatty acid excluding the unsaturated monomer is preferably 20 to 70% with respect to 100% by mass of the monomer component in synthesizing the alkyd resin. %, More preferably 30 to 60% by mass.

Examples of the acid component include acids other than the (semi) drying oil, the (semi) drying oil fatty acid, and the compounds exemplified as the unsaturated fatty acid excluding the unsaturated monomer. Specifically, for example, phthalic acid , Isophthalic acid, terephthalic acid, maleic acid, oxalic acid, malonic acid, glutaric acid, fumaric acid, itaconic acid, succinic acid, adipic acid, trimellitic acid, hemimellitic acid, trimesic acid, merophenic acid, prenitic acid, pyromellitic acid Acid, melittic acid, diphenic acid, hydrogenated trimellitic acid, hydrogenated pyromellitic acid, benzoic acid, rosin, crotonic acid, capric acid, capric acid, lauric acid, myristic acid, pentadecyl acid, palmitic acid, margaric acid, stearic acid, arachidin An acid is mentioned. These may be used alone or in combination of two or more.
Among these, it is preferable to use a polyfunctional carboxylic acid such as phthalic acid, isophthalic acid, terephthalic acid, maleic acid, trimellitic acid or an acid anhydride thereof.

The amount of the acid component to be used is not particularly limited, but is preferably 10 to 50% by mass, more preferably 20 to 40% by mass, with respect to 100% by mass of the monomer component at the time of synthesizing the alkyd resin.

Examples of the polyhydric alcohol component include ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 3-methylpentanediol, 1,4-hexanediol, 1,6-hexanediol, and the like. 2,4-Cyclohexanedimethanol, 2,2,4-trimethyl-1,3-pentanediol, butylethylpropanediol, 1,9-nonanediol, dihydric alcohols such as bisphenol A, bisphenol F, glycerin, trimethylolethane And trimethylolpropane and pentaerythritol. These may be used alone or in combination of two or more.
Among these, it is preferable to use glycerin or pentaerythritol.

The amount of the polyhydric alcohol component to be used is not particularly limited, but is preferably 10 to 50% by mass, more preferably 20 to 40% by mass, with respect to 100% by mass of the monomer component in synthesizing the alkyd resin.

Examples of the epoxy compound include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, resorcinol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, and alkylene glycol diglycidyl ether. These may be used alone or in combination of two or more.
Among these, bisphenol A diglycidyl ether is preferable.

When the epoxy compound is used, the amount thereof to be used is not particularly limited, but is preferably 5 to 50% by mass with respect to 100% by mass of a monomer component at the time of synthesizing an alkyd resin.

The unsaturated monomer is not particularly limited as long as a (meth) acrylic compound is used, and other unsaturated monomers may be used together with the (meth) acrylic compound.

Examples of the (meth) acrylic compound include methyl (meth) acrylate, ethyl (meth) acrylate, n- or iso-propyl (meth) acrylate, n-, iso- or tert-butyl (meth) acrylate, hexyl (for example, Meta) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, tridecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) (Meth) acrylic acid alkyl ester such as acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, glycidyl (meth) acryole , Dicyclopentanyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, allyl (meth) acrylate, β-methylglycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 3,4-epoxy Cycloaliphatic such as cyclohexylethyl (meth) acrylate, 3,4-epoxycyclohexylpropyl (meth) acrylate, allyl glycidyl ether, aromatic ring, heterocyclic ring or vinyl group-containing (meth) acrylic acid ester, 2-hydroxyethyl (meth) Hydroxyl group-containing (meth) acrylates such as acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, ethylene oxide, propylene oxide (Meth) acrylic acid esters containing multiple hydroxyl groups such as glycerol (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate Meta) acrylate, 3-methoxybutyl (meth) acrylate, m- or p-methoxyphenyl (meth) acrylate, o-, m- or p-methoxyphenylethyl (meth) acrylate, phenoxyethyl (meth) acrylate, 2- Alkoxy group-containing (meth) acrylates such as dicyclopentenoxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, dimethylamide Tertiary amino groups and (meth) acryloyl group-containing monomers such as nobutyl (meth) acrylate, dibutylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, (meth) acrylamide, Examples include primary or secondary amino group and (meth) acryloyl group-containing monomers such as butylaminoethyl (meth) acrylate, (meth) acrylonitrile, and (meth) acrylic acid. These may be used alone or in combination of two or more.

The amount of the (meth) acrylic compound used is preferably 10 to 100% by mass, more preferably 20 to 90% by mass, with respect to 100% by mass of the unsaturated monomer.

Examples of the other unsaturated monomers include heterocyclic basic monomers such as vinyl pyrrolidone and vinyl pyridine, vinyl monomers such as styrene, vinyl toluene, α-methylstyrene, vinyl acetate and vinyl propionate, and crotonic acid. Monoesters or dibasic acid monomers such as maleic acid, fumaric acid and itaconic acid, and monoesters of dibasic acid monomers such as monomethyl maleate, monoethyl maleate, monomethyl itaconate and monoethyl itaconate. These may be used alone or in combination of two or more.

The unsaturated monomer preferably contains methyl (meth) acrylate, n- or iso-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, styrene or the like.

The resin (A1) preferably has a structural unit derived from a (meth) acrylic compound, a structural unit derived from an alkyd resin, and a structural unit derived from an epoxy compound, and the structural unit derived from the (meth) acrylic compound 100 mass The content of the structural unit derived from the alkyd resin is preferably 1 to 20 parts by mass, and the structural unit derived from the epoxy compound is preferably 5 to 10 parts by mass.
In addition, the resin (A1) can easily form a coating excellent in a well-balanced manner by corrosion resistance, water resistance, adhesion to a substrate, particularly nonferrous metal substrate and stainless steel substrate, and impact resistance, etc. It is preferable that it is resin which has a bisphenol A structure.

A commercial item may be used as a component (A) containing the said resin (A1), For example, it is a water dispersion type alkyd modified acrylic resin which has a carboxy group and a bisphenol A structure, Yuka resin C-390AE (Yoshimura oil chemistry Co., Ltd.).

<Modified epoxy resin having carboxy group (A2)>
The modified epoxy resin (A2) having a carboxy group is not particularly limited as long as it is a modified epoxy resin having one or more carboxy groups in one molecule. For example, a reaction product of a bisphenol-type epoxy resin, a compound having at least two or more carboxy groups in the molecule, and a compound having reactivity with an epoxy group conventionally known, a bisphenol-type epoxy resin, in the molecule The reaction product of the compound which has an amino group, and (meth) acrylic acid is mentioned.
In order to obtain a resin (A2) having a carboxy group, for example, a compound having a carboxy group may be used as a bisphenol type epoxy resin, and a compound having reactivity with an epoxy group using a compound having a carboxy group When reacting these, a carboxy group may be generated, and after reacting these, modification etc. may be performed so that the resin finally obtained may have a carboxy group.

From the viewpoint of storage stability, the resin (A2) is preferably a resin not containing an epoxy group. Such a resin not having an epoxy group is also a resin having an epoxy group as a raw material, since a common name including "epoxy" is used, the present invention similarly does not have an epoxy group. Even resins are called "modified epoxy resins".

As said bisphenol-type epoxy resin, bisphenol-A epoxy resin, bisphenol F-type epoxy resin, and bisphenol AD-type epoxy resin are preferable, and bisphenol-A epoxy resin is more preferable. These may be used alone or in combination of two or more.

Examples of the compound having at least two or more carboxy groups in the molecule include aliphatic polyvalent carboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid and maleic acid, and phthalic acid. , Aromatic polybasic carboxylic acids such as isophthalic acid, terephthalic acid, hemimellitic acid, trimellitic acid, trimesic acid, merophonic acid, planitic acid, pyromellitic acid, mellitic acid, diphenic acid, hydrogenated trimellitic acid, hydrogenation Alicyclic polyhydric carboxylic acids, such as pyromellitic acid, are mentioned. These may be used alone or in combination of two or more.
In addition, polyvalent carboxylic acids obtained by reacting an anhydride of a compound having at least three or more carboxy groups in the molecule with polyethylene glycol monoalkyl ether can also be used. By using such a polyvalent carboxylic acid, the resin (A2) can be made into a self-emulsifying resin.

The reaction of the bisphenol-type epoxy resin with a compound having at least two or more carboxy groups in the molecule is carried out, for example, using a conventionally known catalyst such as triphenylphosphine and the like at 70 to 200 ° C. for 3 to 15 hours. The method of making it react to some extent is mentioned.

The mixing ratio of the bisphenol type epoxy resin to the compound containing at least two or more carboxy groups in the molecule is such that the carboxy group is about 1.1 to 1.5 moles with respect to 1 mole of the epoxy group. Preferably it is mixed with

Examples of the compound having reactivity with the epoxy group include amines and carboxylic acids, and amines are preferable in terms of ease of reaction with the epoxy group and the like. These may be used alone or in combination of two or more.

The amines are not particularly limited, and examples thereof include aliphatic amines, alicyclic amines, aromatic amines, araliphatic amines, monoamines such as heterocyclic amines, diamines and the like, but they contain a hydroxyl group. Preferred are amines.

The carboxylic acids are not particularly limited, and examples thereof include saturated or unsaturated aliphatic, aromatic or alicyclic, monovalent or polyvalent carboxylic acids. However, carboxylic acids having no hydroxyl group are preferable.

As a method of synthesizing a reaction product of the bisphenol epoxy resin, a compound having at least two or more carboxy groups in the molecule, and a compound having reactivity with an epoxy group, for example, a method of reacting in multiple steps It can be mentioned. More specifically, a resin having at least one carboxy group in the molecule, which is obtained by reacting the bisphenol-type epoxy resin with a compound having at least two carboxy groups in the molecule, and the epoxy The method of making the group and the compound which has reactivity react is mentioned.

The mixing ratio between the epoxy resin having one or more carboxy groups in the molecule and the compound having reactivity with the epoxy group used in the reaction is such that the amines and carboxylic acids remain in the obtained resin (A2) Then, the anticorrosion properties of the obtained anticorrosion coating may be lowered, and when the epoxy group remains in the obtained resin (A2), the storage stability of the present composition may be lowered. The ratio is preferably such that the above-mentioned amines, carboxylic acids and epoxy groups do not remain as much as possible in the resin (A2). For example, a group reactive with the epoxy group is preferably 0.9 per 1 mol of the epoxy group. The amount is about to about 1.3 mol, and more preferably about 1 to about 1.2 mol.

Examples of the compound having an amino group in the molecule include the same compounds as the above-mentioned amines. From the viewpoint of the reactivity with the epoxy group and the storage stability of the obtained resin (A2), monoamines are preferable. These amines may be used alone or in combination of two or more.

As said (meth) acrylic acid, acrylic acid and methacrylic acid are mentioned.

Moreover, as reaction of a bisphenol type epoxy resin, the compound which has an amino group in a molecule | numerator, and (meth) acrylic acid, these may be made to react at once, and you may make it react in multiple steps. In the latter case, the reaction may be carried out in any order, for example, the following method may be mentioned.
Method (1): A method of causing a bisphenol epoxy resin to react with the above-mentioned amines, and causing an addition reaction of (meth) acrylic acid to the obtained reaction product Method (2): the above-mentioned amines and (meth) acrylic acid Method of reacting an adduct obtained by addition reaction with a bisphenol type epoxy resin Further, as these addition reaction, Michael addition reaction etc. may be mentioned.

The reaction of the bisphenol type epoxy resin with the amines in the method (1) can be carried out in the absence of a solvent or in the presence of a solvent. The solvent is preferably a hydrophilic solvent because desolvation after the reaction is unnecessary, cellosolves, propylene glycols and glymes are more preferable, and propyl cellosolve, butyl cellosolve, t-butyl cellosolve, methoxypropanol, Propoxypropanol is more preferred. The reaction temperature is preferably 50 to 120 ° C. in that the reactivity is good.

Next, the method of carrying out the addition reaction of the reaction product thus obtained with (meth) acrylic acid is, for example, the addition reaction under the temperature condition of 50 to 120 ° C. immediately after obtaining the reaction product. Alternatively, after the epoxy group in the reaction product is further reacted with the amines, the reaction product and (meth) acrylic acid are subjected to an addition reaction at a temperature of 50 to 120 ° C. It is also good.

The addition reaction of the amines with (meth) acrylic acid in the method (2) can be carried out in the absence of a solvent or in the presence of a solvent. Here, as the solvent, the above-mentioned hydrophilic solvent is preferable in that desolvation after the reaction becomes unnecessary. The reaction temperature is preferably 50 to 120 ° C. in that the reactivity is good.
In these addition reactions, a catalyst may be used if necessary, and examples of the catalyst include sodium ethoxide and the like.

Next, as a method of reacting the adduct thus obtained and the bisphenol epoxy resin, for example, a method of reacting the adduct and the bisphenol epoxy resin at a temperature of 50 to 120 ° C. may be mentioned. .

The mixing ratio of the amine and (meth) acrylic acid in the addition reaction is such that the vinyl group of (meth) acrylic acid is about 0.7 to 0.9 mole with respect to 1 mole of the amino group of the amine. It is preferable to mix so that

With respect to the mixing ratio of each component, when the amines remain in the resin (A2) to be obtained, the corrosion resistance of the rustproof coating film to be obtained may be lowered, and an epoxy group is present in the resin (A2) to be obtained. If it remains, the storage stability of the present composition may be lowered, so that the ratio is preferably such that the above-mentioned amines and epoxy groups do not remain as much as possible in the obtained resin (A2). The amount of amine is about 0.9 to 1.3 moles, more preferably about 1 to 1.2 moles.

A commercial item may be used as a component (A) containing the said resin (A2), for example, Epiclon C-250EP (DIC Corporation) which is a water dispersion-type modified epoxy resin which has a carboxy group and a bisphenol A structure. Manufactured by

<Aqueous epoxy resin (B)>
The component (B) may be any compound other than the component (A), and preferably has two or more epoxy groups in one molecule. The component (B) may be an emulsion or dispersion, and the resin physical values such as the molecular weight of the epoxy resin and the epoxy equivalent are not particularly limited.
The component (B) contained in the present composition may be one type, or two or more types.

Examples of the component (B) include bisphenol A epoxy resin, bisphenol F epoxy resin, novolak epoxy resin (eg, phenol novolac epoxy resin, cresol novolac epoxy resin), alicyclic epoxy resin, aliphatic A modified epoxy resin is mentioned.

The content of the epoxy resin in 100% by mass of the component (B) is preferably 35 to 100% by mass, more preferably from the viewpoint of being able to obtain a coating composition which is excellent in ease of preparation, storage stability, etc. Is 45 to 80% by mass.
The remainder of the component (B) may contain water, and may contain conventionally known components such as surfactants, if necessary.

A commercial item may be used as said component (B), For example, Epiclon EM-85-75W, Epiclon EM-8358 (all are water-dispersed bisphenol A epoxy resins which do not have a carboxy group) DIC (manufactured by DIC Corporation), Adeka Resin C-110 EP (manufactured by ADEKA Corporation), and the like.

The content of the nonvolatile component of the component (B) can easily form a coating film excellent in a well-balanced manner by corrosion resistance, water resistance, adhesion to a substrate, particularly nonferrous metal substrate and stainless steel substrate, and impact resistance. Preferably, 1 to 30 parts by mass, more preferably 1 to 25 parts by mass, still more preferably 5 to 20 parts by mass, particularly preferably 5 to 20 parts by mass with respect to 100 parts by mass of the nonvolatile component of the component (A). It is 15 parts by mass.

<Water (C)>
The components (A) and (B) may contain water, and the components (A) and (B) preferably contain water, but preparation of the present composition is preferable. It is preferable to further add water (C) to the present composition, in order to make the composition easier to use and to improve the storage stability of the composition. When the present composition comprises the first agent containing the component (A) and the second agent containing the component (B), the preparation ease and storage stability of the first agent and the second agent are further increased. From the point of improvement etc., it is preferable to mix the component (C) to the first agent and / or the second agent, and it is preferable to mix the component (C) to the first agent and the second agent.
The component (C) is not particularly limited, and tap water and the like may be used, but it is preferable to use ion exchange water and the like.
The content of water in the composition (the total of water which may be contained in the components (A) and (B) and other water (C)) is not particularly limited, but preferably 10 to 50% by mass It is.

<Pigment (D)>
Examples of the component (D) include an extender pigment, a color pigment, and an anticorrosion pigment (D1). These may be used alone or in combination of two or more.
When the present composition is a multicomponent composition comprising a first agent and a second agent, component (D) may be incorporated into either one of the first agent and the second agent, or in both Although it may be blended, blending into the first agent is preferable.

The content of the component (D) in the present composition can easily form a coating film excellent in good balance by corrosion resistance, water resistance, adhesion to a substrate, particularly nonferrous metal substrate and stainless steel substrate, and impact resistance. From the point of view of etc., the content is preferably 45 to 75% by mass, more preferably 50 to 70% by mass, with respect to 100% by mass of the nonvolatile matter of the present composition.

The pigment volume concentration (PVC) in the present composition can easily obtain a composition which is more excellent in coating workability, and easily obtain a coating which is more excellent in adhesion to a substrate by stress relaxation and water resistance. From the viewpoint of being able to do etc, it is preferably 20 to 50%, more preferably 20 to 45%, still more preferably 20 to 40%, particularly preferably 20 to 38%.
If PVC falls below the above range, the effect of stress relaxation due to a decrease in the corrosion resistance of the resulting coating film and incorporation of the pigment tends to be poor, and if it exceeds the above range, the impact resistance of the coating film obtained The paintability tends to be reduced as well as the properties are reduced.

The PVC refers to the total volume concentration of the pigment relative to the volume of non-volatile components in the present composition. Specifically, PVC can be obtained from the following equation.
PVC [%] = total volume of all pigments in the composition × 100 / volume of non-volatile components in the composition

The nonvolatile content (solid content) of the composition means the mass percentage of the coating (heating residue) after the reaction curing (heating) of the composition sufficiently, or the coating (heating residue) itself Do. The non-volatile component is obtained by weighing 1 ± 0.1 g of the present composition (for example, a composition immediately after mixing the first agent and the second agent) in a flat bottom plate according to JIS K 5601-1-2: 2008, By spreading uniformly using a wire of known mass, drying at 23 ° C. for 24 hours, and measuring the mass of the heating residue and the wire when heated at a heating temperature of 125 ° C. for 1 hour (normal pressure) It can be calculated. In addition, this non volatile matter is a value equivalent to the total amount of solid content (components other than a solvent) of the raw material component used for this composition.

The volume of the non-volatiles in the present composition can be calculated from the mass and the true density of the non-volatiles of the present composition. The mass and the true density of the non-volatile components may be measured values or values calculated from raw materials used.
The volume of the pigment can be calculated from the mass and true density of the pigment used. The mass and true density of the pigment may be measured values or values calculated from the raw materials used. For example, it can be calculated by separating the pigment and other components from the nonvolatile matter of the present composition, and measuring the mass and true density of the separated pigment.

<Extra pigment>
The extender pigment is not particularly limited, and is a pigment other than the following color pigment and rust preventive pigment.
Examples of the extender pigment include, for example, conventionally known talc, mica, barium sulfate (including precipitated barium sulfate and barium sulfate sulfate), (potassium) feldspar, kaolin, alumina white, clay, magnesium carbonate, barium carbonate, Examples include calcium carbonate, dolomite and silica. Among these, talc, barium sulfate and (potassium) feldspar are preferable.
One extender pigment may be used, or two or more extender pigments may be used.

The content in the case of blending the above-mentioned extender pigment in the present composition makes it easy to form a coating film which is excellent in balance by corrosion resistance, water resistance, adhesion to a substrate, particularly nonferrous metal substrate and stainless steel substrate and impact resistance. From the viewpoint of formation, etc., the content is preferably 15 to 60% by mass, more preferably 20 to 55% by mass, with respect to 100% by mass of the non volatile matter of the present composition.

<Colored pigment>
The color pigment is not particularly limited, but is a pigment other than the following rust preventive pigment.
Examples of the coloring pigment include, for example, conventionally known inorganic pigments such as carbon black, titanium dioxide (titanium white), iron oxide (red iron oxide), yellow iron oxide and ultramarine blue, and organic pigments such as cyanine blue and cyanine green. Be Among these, titanium white, carbon black and red iron oxide are preferable.
The color pigments may be used alone or in combination of two or more.

The content of the color pigment in the present composition is preferably 0.1 to 25% by mass, more preferably 0.5 to 20% by mass, with respect to 100% by mass of the nonvolatile matter of the composition. is there.

<Antirust pigment (D1)>
The present composition preferably contains an anticorrosion pigment (D1) as the component (D) from the viewpoint that a coating film more excellent in corrosion resistance and water resistance can be easily obtained.
As the component (D1), one type may be used, or two or more types may be used.

The component (D1) is preferably a metal phosphate anticorrosive pigment from the viewpoint that the above effects are easily obtained, etc., and zinc phosphate, molybdenum phosphate, aluminum phosphate, and strontium phosphate are preferred. It is more preferable that it is a rust preventive pigment. More specifically, for example, the hydrates of aluminum molybdenum polyphosphate, the hydrates of molybdenum aluminum zinc polyphosphate, the hydrates of aluminum phosphate phosphomolybdate, strontium zinc phosphate silicate, zinc molybdenum phosphate polyphosphate as these rust preventive pigments. Hydrates, hydrates of calcium polyphosphate strontium silicates, hydrates of zinc aluminum phosphate polysilicates, zinc phosphates, and organic modifications thereof, preferably organically modified aluminum molybdenum polyphosphates Hydrates, aluminum phosphomolybdate, hydrate of zinc molybdenum phosphate, zinc phosphate.

The content in the case of blending the component (D1) in the present composition is a coating film excellent in good balance by corrosion resistance, water resistance, adhesion to a substrate, particularly nonferrous metal substrate and stainless steel substrate, and impact resistance. The amount is preferably 0.1 to 15% by mass, and more preferably 1 to 15% by mass, with respect to 100% by mass of the non volatile matter of the present composition from the viewpoint of easy formation.
If the content of the component (D1) is below the above range, the corrosion resistance and the water resistance of the resulting coating film tend to be lowered, and if it exceeds the above range, the adhesion to the substrate and the impact resistance As it decreases, the water resistance tends to decrease.

<Other ingredients>
In addition to the above components, the composition of the present invention may, if necessary, contain known dispersants, film-forming assistants, antifoaming agents, thickeners, anti-settling agents, as long as the effects of the present invention are not impaired. A dryer, a curing accelerator, an organic solvent, etc. may be blended.

[Organic solvent]
Since the composition may be frozen in winter due to the inclusion of water, the composition may be used for the purpose of suppressing the freezing, or for the purpose of obtaining appropriate coating workability as a coating composition, etc. From this, it is possible to use water-miscible organic solvents in any amount.
Examples of such organic solvents include alcohol solvents having 1 to 3 carbon atoms such as isopropyl alcohol, and ether solvents such as ethylene glycol monomethyl ether, ethylene glycol monobutyl ether and propylene glycol monomethyl ether.

«Anti-corrosion coating, substrate with anti-corrosion coating»
The anticorrosive coating according to an embodiment of the present invention (hereinafter also referred to as "the present coating") is formed using the present composition, and the anticorrosion coated group according to an embodiment of the present composition. The material (hereinafter also referred to as “the coated film-coated substrate”) is a laminate including the present coated film and a substrate (substrate).

The material of the base is not particularly limited. For example, steel (eg, iron, steel, mild steel), non-ferrous metal (eg, aluminum, copper, brass, galvanized, zinc sprayed), stainless steel (eg, SUS 304, etc.) SUS 410) may be mentioned, and the surface of the substrate may be coated with a coating film formed of a coating composition such as an alkyd resin system, an acrylic resin system, or an epoxy resin system.
When mild steel (SS400, etc.) is used as the substrate, for example, the surface of the substrate is polished by grit blasting if necessary, and the substrate adjustment (example: arithmetic average roughness (Ra) is 30 to 75 μm) It is desirable to adjust to a certain extent.

The substrate is not particularly limited, and can be used without limitation for substrates requiring anticorrosion and water resistance, but from the viewpoint of exhibiting the effect of using the present composition, etc., it is preferable. Bridges, tanks, plants, and (land) structures such as containers (for transportation).

The dry film thickness of the coating film is not particularly limited, but the coating film has sufficient corrosion resistance and water resistance, and is excellent in a well-balanced manner by adhesion to a substrate, particularly nonferrous metal substrate and stainless steel substrate and impact resistance. The thickness is usually 10 to 100 μm, preferably 20 to 60 μm from the viewpoint of obtaining.

Further, the substrate with the present coating film is a laminate including the present coating film and the object to be coated (substrate), and it is possible to form a top coat film further excellent in weather resistance and appearance on the present coating film. Good. As such a top coat film, the coat formed from various top coat water-based paint compositions, such as an acrylic resin system, an acrylic silicone resin system, a urethane resin system, a silicone resin system, and a fluorine resin system, is mentioned, for example.

«Method of manufacturing base material with anti-corrosion coating film»
The method for producing a substrate with a rustproof coating according to an embodiment of the present invention (hereinafter also referred to as "the present method") includes the following steps [1] and [2].
Step [1]: A step of coating the present composition on a substrate Step [2]: a step of drying the present composition coated on a substrate to form an anticorrosion coating

<Step [1]>
The coating method in the step [1] is not particularly limited, and examples thereof include conventionally known methods such as airless spray coating, spray coating such as air spray coating, brush coating, and roller coating. Among these, spray coating is preferable from the viewpoint of being able to easily coat a large-area substrate such as the above-mentioned structure.
In the case of such coating, it is preferable to coat so that the dry film thickness of the obtained coating film may become the said range.

Although the conditions of the spray coating may be appropriately adjusted according to the dry film thickness to be formed, for example, in the case of airless spray coating, the primary (air) pressure: about 0.3 to 0.6 MPa, secondary (paint ) Pressure: about 10 to 15 MPa, gun moving speed of about 50 to 120 cm / second is preferable.

The viscosity of the composition suitable for spray coating is preferably 6 at a viscosity of 23 ° C. using a B-type viscometer (Model: VT-06, manufactured by Rion Co., Ltd.) as a measuring instrument. And preferably from 8,000 to 12,000 mPa · s.

In addition, when coating this composition, you may adjust to the viscosity of a suitable coating composition as needed. It is preferable to use water as a diluent used for such viscosity adjustment.
In this case, it is preferable to use a diluent so as to obtain a paint viscosity suitable for each coating method. For example, in the case of airless spray coating, the amount of diluent used per 100 parts by mass of the present composition is preferably 1 to 30 It is a mass part.

<Step [2]>
The drying conditions in the step [2] are not particularly limited, and may be appropriately set according to the method of forming a coating film, the type of substrate, the application, the coating environment, etc. The drying temperature is usually 5 to 35.degree. C., more preferably 10 to 30.degree. C. When drying with a hot air drier or the like, the temperature is usually 30 to 90.degree. C., more preferably 40 to 80.degree. According to the present composition, the composition can be cured even by such normal temperature drying.
On the other hand, the drying time varies depending on the method of drying the coating film, and is usually 1 hour to 7 days, preferably 1 day to 3 days in the case of normal temperature drying, and is usually 5 minutes to 60 in the case of drying with a hot air drier or the like. Minutes, preferably 10 minutes to 30 minutes.

The present invention will be described in more detail by way of examples, but the present invention is not limited thereto. In addition, the compounding quantity in a table | surface represents a "mass part" unless there is particular description.
Raw materials used in the following Examples and Comparative Examples are shown in Table 1 below.

Example 1
In a container, 9.7 parts by mass of ion-exchanged water, 1 part by mass of a dispersant, 0.1 parts by mass of an antifoaming agent, 14 parts by mass of talc, 13 parts by mass of inert barium sulfate, and 10 parts by mass of titanium oxide 0.1 parts by mass of an anti-settling agent was added, and dispersed with a high-speed disper to a particle gauge of 40 μm or less (according to JIS K 5600-2-5: 1999) to prepare a mill base. After adding 45 parts by mass of the aqueous resin A1, 1 part by mass of the film-forming aid, 0.1 part by mass of the antifoaming agent, and 1 part by mass of the thickener to the obtained mill base, they are mixed by a high speed disper , The first agent was prepared.
Further, 2.5 parts by mass of water-dispersed epoxy B1 and 2.5 parts by mass of ion-exchanged water were added to another container, and then mixed with a high-speed disper to prepare a second agent.
The obtained first and second agents were mixed immediately before coating to prepare a coating composition.

[Examples 2 to 19 and Comparative Example 2]
Each paint composition was prepared in the same manner as in Example 1 except that the raw materials described in Tables 2 to 4 were used in the amounts described in the tables.

Comparative Example 1
In a container, 11.7 parts by mass of ion-exchanged water, 1 part by mass of a dispersant, 0.1 parts by mass of an antifoaming agent, 11 parts by mass of talc, 11 parts by mass of inert barium sulfate, and 10 parts by mass of titanium oxide Add 5 parts by mass of Anti-corrosion pigment 1 and 0.1 parts by mass of anti-settling agent, disperse with a high-speed disper to a particle gauge of 40 μm or less (according to JIS K 5600-2-5: 1999), and mill base Made. After adding 48 parts by mass of the aqueous resin A1, 1 part by mass of the film-forming aid, 0.1 part by mass of the antifoaming agent, and 1 part by mass of the thickener to the obtained mill base, they are mixed by a high speed disper The paint composition of Comparative Example 1 was prepared.

Comparative Example 3
A paint composition was prepared in the same manner as Comparative Example 1 except that the raw materials listed in Table 2 were used in the amounts listed in the table.

<Preparation of acrylic resin-based aqueous paint>
In a container, 6 parts by mass of ion exchange water, 1 part by mass of a dispersant, 0.1 parts by mass of an antifoaming agent, 15 parts by mass of titanium oxide, 15 parts by mass of an inert barium sulfate, 0. One part by mass was added, and dispersed with a paint shaker to a particle gauge of 30 μm or less (in accordance with JIS K 5600-2-5: 1999) to prepare a mill base. After adding 55 parts by mass of a water-dispersed acrylic resin, 4 parts by mass of a film-forming agent, 0.1 parts by mass of an antifoaming agent and 1 part by mass of a thickener to the obtained mill base, high speed disper The mixture was mixed to prepare an acrylic resin-based aqueous paint.

[Method of creating test body]
The viscosity of each paint composition of the examples and comparative examples was adjusted using ion exchanged water so that the viscosity at 23 ° C. measured using the B-type viscometer was 10,000 mPa · s.
Each paint composition after viscosity adjustment is applied on a stainless steel plate (SUS410) by air spray so that the average dry film thickness is 40 μm, dried at normal temperature for 10 minutes, and then dried at 50 ° C. for 15 minutes. To form a primer coating. Thereafter, the above-mentioned acrylic resin-based water-based paint was applied on the undercoat film by air spray so that the average dry film thickness would be 40 μm, and a top coat film was formed under the same dry conditions as the undercoat film. After forming the top coat, it was dried for 7 days in an environment of 23 ° C. and 50% relative humidity to prepare a test body (substrate with a coat) used in various coat performance evaluation tests described later.
In this method, the undercoat film was formed by hot-air drying at 50 ° C. for 15 minutes to promote drying, but each coating composition obtained in the examples was 1.5 hours at normal temperature (23 ° C.) The undercoating film (cured film) could be formed also by drying.

<Initial adhesion>
[Stickness test on grids]
The adhesion test (cross-cut method) of 25 squares of 2 mm × 2 mm was carried out according to JIS K 5600-5-6: 1999 on each of the above-mentioned test bodies, and the 25 squares accounted for according to the following evaluation criteria. The adhesion was evaluated by the ratio (%) of the area of the coating film peeled from the stainless steel plate to the coating film area of 100%.
In addition, it can be said that there is no problem in terms of adhesion if the following evaluation is "4" or more.

(Evaluation criteria)
5: The area of the peeled coating is 5% or less 4: The area of the peeled coating is more than 5% and 15% or less 3: The area of the peeled coating is more than 15% and 35% or less 2: Peeled The area of the coating is more than 35% and not more than 65% 1: The area of the peeled coating is more than 65%

[Impact resistance test]
For each of the test specimens mentioned above, using an impact tester (manufactured by BYK-Gardener), a 2-pound weight with a spherical tip (diameter: 0.625 inches) against the coated surface (front surface) of the test specimen It was dropped from a height of 30 inches from the test body. A cut is made until it reaches the base material (SUS410) in 1.5 cm steps in a cross shape around the falling part of the weight of the coating surface, and after the transparent pressure-sensitive adhesive tape is attached, the tape is peeled off and coated The maximum peel width of the film was measured. Impact resistance (impact resistance test (Table)) was evaluated according to the following evaluation criteria.
In addition, a weight is dropped to the surface (back) opposite to the coating film surface of the test body, and the maximum peeling width is measured in the same manner as described above for the coating film surface corresponding to the falling portion of the weight. Impact resistance (impact resistance test (back)) was evaluated according to the criteria. In addition, in the location which the coating film peeled, the largest peeling width points out the length where the line tied so that it may pass through the center of the fall place of a weight becomes the longest.
In addition, it can be said that impact resistance has no problem in practical use if the following evaluation is "3" or more.

(Evaluation criteria)
5: The coating did not peel 4: The maximum peeling width of the coating is 8 mm or less 3: The maximum peeling width of the coating is more than 8 mm, 12 mm or less 2: The maximum peeling width of the coating is more than 12 mm, 16 mm or less 1: The maximum peeling width of the coating is greater than 16 mm

<Secondary adhesion>
After the salt spray test described later was performed on each of the test bodies, the secondary adhesion of each test body was evaluated according to the same test method and evaluation criteria as those for the cross-cut adhesion test and the impact resistance test.

<Water resistance>
[Water immersion test]
A water immersion test in which each of the test specimens is immersed in water at 23 ° C. for 96 hours (4 days) or 168 hours (7 days) based on JIS K 5600-6-2: 1999 for liquid resistance (water immersion method) Carried out. Water resistance was evaluated according to the evaluation criteria described later.
In addition, water resistance does not have a problem in practical use if the following evaluation of the test body after being immersed in water for 96 hours is "3" or more, and even after immersion in water for 168 hours, the following evaluation is "3" When it is above, it can be said that the primer coating has extremely high water resistance.

(Evaluation criteria)
5: Both rust and swelling did not occur. 4: No blistering occurred, but with respect to the entire area of the coated surface of the test body,
Rust generation area is 0.03% or less 3: No blistering has occurred, but with respect to the entire area of the coated surface of the test body,
The occurrence area of rust is more than 0.03% and less than 0.1% 2: No blistering has occurred, but with respect to the entire area of the painted surface of the test body,
Rust generation area is larger than 0.1% and 0.3% or less 1: The occurrence of blistering and / or the rust generation area is larger than 0.3% with respect to the total area of the coated surface of the test body

<Corrosion resistance>
Salt spray test
Each sample is placed in a salt spray tester under salt spray conditions of salt concentration 5 wt%, temperature 35 ° C., relative humidity 98% based on JIS K 5600-7-1: 1999 for neutral salt spray resistance. A salt spray test was performed by holding for 200 hours. The corrosion resistance was evaluated by evaluating each test body after this salt spray test according to the evaluation criteria similar to the said water immersion test.
In addition, if the said evaluation is "3" or more, it can be said that corrosion resistance does not have a problem in practical use.

In each of the above tests, even when the substrate of the coated substrate (test body) is changed from a stainless steel plate to an aluminum substrate or a steel plate, it can be obtained from the coating composition obtained in the example as described above. The coated film was excellent in adhesion to these substrates.

It was found that this coating film is excellent in initial adhesion, secondary adhesion, water resistance and corrosion resistance. In addition, it was found that the present coating film is excellent in adhesion to a substrate, particularly to a nonferrous metal substrate, a stainless steel substrate, and further to an iron-based substrate, and also excellent in adhesion to a top coating film. When a conventional composition such as an alkyd resin system is used, there is a tendency for coating film defects due to lifting if the above-mentioned interval is insufficient, but according to the present composition, the formation of the present coating film It was found that coating film defects such as lifting hardly occur and the desired laminated coating film can be easily formed regardless of the range from the above to the formation of the top coating film.

Claims (12)

1. An aqueous anticorrosion paint composition comprising an aqueous resin (A) having one or more carboxy groups in one molecule, and an aqueous epoxy resin (B) other than the aqueous resin (A).
2. The aqueous anticorrosion according to claim 1, wherein the aqueous resin (A) contains one or more selected from an aqueous alkyd modified acrylic resin (A1) having a carboxy group and an aqueous modified epoxy resin (A2) having a carboxy group. Paint composition.
3. The aqueous anticorrosion paint composition according to claim 2, wherein the alkyd-modified acrylic resin (A1) and the modified epoxy resin (A2) are resins having a bisphenol A structure.
4. The aqueous solution according to any one of claims 1 to 3, wherein the aqueous epoxy resin (B) is contained in an amount of 1 to 30 parts by mass as a nonvolatile matter based on 100 parts by mass of the nonvolatile matter of the aqueous resin (A). Anticorrosion paint composition.
5. The aqueous solution according to any one of claims 1 to 4, which is a multicomponent type comprising a first agent containing the aqueous resin (A) and a second agent containing the aqueous epoxy resin (B). Anticorrosion paint composition.
6. The aqueous anticorrosive coating composition according to any one of claims 1 to 5, further comprising a pigment (D).
7. The aqueous anticorrosion paint composition according to claim 6, wherein the pigment (D) contains an anticorrosion pigment (D1).
8. The aqueous anti-corrosive paint composition according to claim 6 or 7, wherein the pigment volume concentration (PVC) in the aqueous anti-corrosive paint composition is 20 to 50%.
9. A rustproof coating film formed from the aqueous rustproof coating composition according to any one of claims 1 to 8.
10. A substrate with a rust-preventive coating, comprising the rust-preventive coating according to claim 9 and a substrate.
11. The anticorrosion coated substrate according to claim 10, wherein the substrate is a nonferrous metal or stainless steel.
12. The manufacturing method of the base material with a rustproof coating film containing the following process [1] and [2].
    [1] A step of applying the aqueous anticorrosion paint composition according to any one of claims 1 to 8 to a substrate [2] drying an aqueous anticorrosion paint composition coated on a substrate Process to form rustproof coating film