CN1093155C - Novel resin-coated metallic pigment and metallic coating material containing the pigment - Google Patents

Abstract

A resin-coated metal pigment, and a metal paint using the resin-coated metal pigment, which can be formed into a paint having excellent weather resistance, chemical resistance and gloss and excellent in water-based paint Storage-stable metal coating film; made from the following three raw materials (A), (B) and (C), wherein (A) is a free radical polymerizable unsaturated carboxylic acid, and/or has a free radical At least one selected from the monoester or diester of phosphoric acid or phosphonic acid with a polymerizable double bond, and/or a coupling agent with a radically polymerizable double bond, (B) having three or more radically polymerizable A monomer with a double bond, (C) is a polymerization initiator, first add (A) to treat the metal pigment, then slowly add at least one of (B) and (C) to form a polymerized resin layer on the metal surface.

Description

New resin-coated metallic pigments and metallic paints using the same

The present invention relates to a novel resin-coated metallic pigment, in particular, to a resin-coated metallic pigment which, when used as a paint pigment, provides excellent chemical resistance, gloss, Weatherable metallic coatings with excellent storage stability in water-based coatings. In addition, the present invention also relates to a novel metallic paint composed of the above-mentioned resin-coated metallic pigment, resin for paint, and diluent. Metallic coating with excellent storage stability.

For a long time, metallic pigments have been used in metallic paints, printing inks, blended into plastics, etc. to achieve aesthetic effects while emphasizing the metallic feel.

However, coating films or resin molded articles obtained using conventional metallic pigments have insufficient chemical resistance such as acid resistance and alkali resistance, and water resistance, and also have disadvantages of poor weather resistance. That is, the painted surface becomes discolored and the gloss lowers after a period of time, so their uses are limited. Therefore, it is strongly desired to provide a metallic pigment excellent in chemical resistance and weather resistance and also excellent in storage stability.

As an improvement to this problem, it has been proposed to apply resin coating to the metal pigment component.

It is known that an aluminum paste is dispersed in an organic solvent in which an ethylenically unsaturated monomer is dissolved and heated in the presence of a polymerization initiator to obtain an aluminum paste coated with a resin having excellent chemical resistance (Japanese Patent Laid-Open Sho Bulletin No. 51-11818). However, the resin-coated aluminum paste produced according to this method does not have sufficient chemical resistance and does not reach a practical level.

In addition, there is a method of dispersing aluminum paste in an organic solvent, first absorbing a radically polymerizable unsaturated carboxylic acid, etc., and then coating the surface with a polymer produced from a monomer having three or more radically polymerizable double bonds Proposal (Japanese Patent Publication No. 1-49746). In this method, in order to realize sufficient alkali resistance, it is necessary to add a considerable amount of monomer for coating resin, and at the same time, not only the gloss is lowered, but also there is a problem that the metallic feeling is significantly different.

In addition, JP-A-7-3185 describes a metallic pigment composed of coating silicone and coating a synthetic resin that forms a three-dimensional crosslink through covalent bonds on the silicone coating. However, this metallic pigment is still not considered to have sufficient chemical resistance.

In addition, when the resin-coated aluminum paste and the aluminum paste not coated with resin are used in an aqueous medium, they react with water to generate hydrogen gas, which greatly reduces the metallic luster. Therefore, when using it as a water-based paint, it is necessary to take countermeasures such as exhaust gas.

For the purpose of improving the uniformity and smoothness of the coating resin film, there is a proposal of coating with a copolymer of a radically polymerizable monomer and an oligomer (JP-A-64-40566). This method also has the problem of generating a large amount of hydrogen gas when it is used as a water-based paint, and also has problems in storage stability due to a significant decrease in metallic luster.

In order to solve the problems existing in the existing metallic pigments, the inventors of the present invention have conducted in-depth studies and found that: from radically polymerizable unsaturated carboxylic acids, monoesters or diesters of phosphoric acid or phosphonic acids having radically polymerizable double bonds, And at least one of coupling agents having radically polymerizable double bonds is selected, and a monomer having 3 or more radically polymerizable double bonds in one molecule and a polymerization initiator are continuously added thereto, or a monomer having 3 or more radically polymerizable double bonds is continuously added thereto. Any one of monomers or polymerization initiators with more than two free radically polymerizable double bonds can achieve the purpose by coating the surface of the metal pigment with the copolymer obtained after the above operation, and thus the present invention has been completed.

That is, the present invention has the following characteristics:

(1) A resin-coated metal pigment obtained from the following three raw materials (A), (B), and (C), wherein (A) is a radically polymerizable unsaturated carboxylic acid, and/or has a radical At least one selected from the monoester or diester of phosphoric acid or phosphonic acid with a polymerizable double bond, and/or a coupling agent having a radically polymerizable double bond; (B) has 3 or more radically polymerizable double bonds (C) is a polymerization initiator, first add (A) to treat the metal pigment, and then slowly add at least one of (B) and (C), thereby forming a polymerized resin layer on the metal surface.

(2) The resin-coated metallic pigment described in (1) above, wherein the monomer having three or more radically polymerizable double bonds as (B) is a monomer having three radically polymerizable double bonds and A mixture of monomers having 4 or more free radically polymerizable double bonds, and the amount of the monomer having 4 or more free radically polymerizable double bonds is relative to the amount of the aforementioned monomer having 3 or more free radically polymerizable double bonds The total amount is 10% by weight to 60% by weight.

(3) The resin-coated metallic pigment described in (1) or (2) above, wherein the time for adding at least one of the above (B) and the above (C) is 20% or more of the total polymerization time.

(4) The resin-coated metal pigment described in any one of the above (1)-(3), wherein the molecular weight of the functional group of each monomer having 4 or more radically polymerizable double bonds is 30 or more and 200 or less .

(5) The resin-coated metallic pigment described in any one of (1) to (4) above, which has an alkali resistance of 2.0 or less.

(6) A metallic paint comprising the resin-coated metallic pigment described in any one of (1) to (5) above.

(7) A method for preparing a resin-coated metal pigment, which is characterized in that the following three raw materials (A), (B) and (C) are used, wherein (A) is obtained from a radically polymerizable unsaturated carboxylic acid, and/or monoester or diester of phosphoric acid or phosphonic acid with free radical polymerizable double bonds, and/or at least one selected from the coupling system with free radical polymerizable double bonds; (B) has more than 3 free (C) a polymerization initiator, first add (A) to treat the metal pigment, and then slowly add at least one of (B) and (C) to form a polymer on the metal surface resin layer.

The resin-coated metallic pigment obtained by the present invention exhibits excellent chemical resistance that has never been seen before, can maintain the luster attached to the raw metallic pigment, and has excellent storage stability.

The metal pigment used in the present invention contains aluminum, copper, zinc, iron, nickel, and/or alloys thereof, preferably aluminum. Its shape can be flake, spherical, needle and other granular. The preferred particle size of metallic pigments varies depending on the application. For coatings and printing, the average particle size is preferably about 1 to 10 μ, and when blended into plastics, it is preferably about 1 to 200 μ, and these ranges are not particularly limited.

The radically polymerizable unsaturated carboxylic acid in the present invention includes acrylic acid, methacrylic acid, itaconic acid, fumaric acid, and the like, and one or more of them are used as a mixture. The amount used may vary depending on the type and characteristics of the metal pigment, especially the surface area of the metal pigment, but generally speaking, it is between 0.01 parts by weight and 10 parts by weight relative to the metal pigment, more preferably 0.1 parts by weight parts to 5.0 parts by weight. When it is less than 0.01 parts by weight, the effect of the present invention, that is, chemical resistance such as alkali resistance or acid resistance cannot be well exerted. In addition, when a monomer having 3 or more radically polymerizable double bonds is polymerized on the surface of the metallic pigment , the polymerization system may gel and cannot be stirred. Moreover, when using more than 10 weight part, the effect, such as chemical resistance, does not increase.

As the phosphoric acid or phosphonic acid ester with a radically polymerizable double bond in the present invention, monoester or diester of phosphoric acid or phosphonic acid can be used, for example: 2-methacryloxyethyl phosphate, di-phosphonic acid 2-methacryloyloxyethyl ester, tri-2-methacryloyloxyethyl phosphate, 2-acryloyloxyethyl phosphate, di-2-acryloyloxyethyl phosphate, tri- 2-Acryloyloxyethyl Ester, Diphenyl-2-Acryloyloxyethyl Phosphate, Dibutyl-2-Methacryloyloxyethyl Phosphate, Dioctyl-2-Acryloyloxy Phosphate Ethyl ester, 2-methacryloxypropyl phosphate, bis(2-chloroethyl) vinyl phosphonate, diallyl dibutyl phosphonosuccinate, etc., one or both of them can be used mixture of the above.

Among phosphoric acid or phosphonic acid esters having a radically polymerizable double bond, phosphoric acid monoesters are preferable. Its reason can be considered because the phosphate radical has 2 OH groups, so it is more firmly fixed on the surface of the aluminum ion, and the more preferred phosphoric acid monoester is the monoester with methacryloyloxy group and acryloyloxy group, such as 2-Methacryloyloxyethyl Phosphate, 2-Acryloyloxyethyl Phosphate.

The amount used varies depending on the type and characteristics of the metallic pigment, especially its surface area. Generally speaking, relative to 100 parts by weight of the metallic pigment, it is between 0.01 parts by weight and 30 parts by weight. More preferably, it is 0.1 weight part - 20 weight part. When the content is less than 0.01 parts by weight, the effect of the present invention, that is, chemical resistance such as alkali resistance, cannot be exhibited well, and the effect cannot be expected to increase even if it is used more than 20 parts by weight.

As the coupling agent having a radically polymerizable double bond in the present invention, there are silane-type coupling agents, titanate-type coupling agents, aluminum-type coupling agents, and the like.

Silane-type coupling agents include, for example, γ-methacryloxypropyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(β- Methoxyethoxy) silane, etc.

Examples of the titanate-type coupling agent include isopropyl isostearyl diacryloyl titanate and the like.

Examples of aluminum-type coupling agents include acetylalkoxyaluminum diisopropionate, zircoaluminate and the like.

The amount of the coupling agent with a radically polymerizable double bond varies depending on the type and characteristics of the metallic pigment, especially the surface area, and is generally between 0.01 and 20 parts by weight relative to 100 parts by weight of the metallic pigment. More preferably between 0.1 parts by weight and 10 parts by weight. When the content is less than 0.01 parts by weight, the effect of the invention, that is, chemical resistance such as alkali resistance, cannot be exhibited well, and when the content exceeds 20 parts by weight, the effect does not increase.

Generally, when treating metallic pigments, it is desirable to treat them in an inert solvent in order to prevent the reaction of the metallic pigment itself with water.

Because free-radically polymerizable unsaturated carboxylic acids, and/or monoesters or diesters of phosphoric acid and phosphonic acids with free-radically polymerizable double bonds have high solubility in inert solvents, they can be uniformly dispersed relatively easily, so chemical resistance It has good quality and is not easy to cause the problem of decreased storage stability in water-based paints, so it is preferred.

Examples of the monomer (B) having three or more radically polymerizable double bonds in the present invention include trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, tetramethylolpropane Methane tetraacrylate, tetramethylolpropane tetraacrylate, di-trimethylolpropane tetraacrylate, di-trimethylolpropane hexaacrylate, pentaerythritol tetraacrylate, di-pentaerythritol hexaacrylate, etc., can Use one or a mixture of more than one of these.

Among the monomers (B) having 3 or more radically polymerizable double bonds in the present invention, the monomer having 4 or more radically polymerizable double bonds is preferably di-trimethylolpropane tetraacrylate , Pentaerythritol tetraacrylate, di-pentaerythritol hexaacrylate.

The usage amount of the monomer (B) with 3 or more free radical polymerizable double bonds in the present invention is between 2 parts by weight and 50 parts by weight relative to 100 parts by weight of the metal component of the metal pigment, more preferably 3 parts by weight to 40 parts by weight. When it is less than 2 parts by weight, the effect of the invention, that is, chemical resistance is low, and if it exceeds 50 parts by weight, the effect cannot be expected to increase, and the basic properties of metallic paints such as brightness and gloss will be reduced, making it difficult to use for practical use.

And use the monomer with 3 free radical polymerizable double bonds and the monomer with 4 or more free radical polymerizable double bonds as the monomer with 3 or more free radical polymerizable double bonds in the present invention (B ), the effect of the present invention can be enhanced. The ratio thereof is 10 to 60% by weight of the monomer having 4 or more radically polymerizable double bonds, more preferably 20% to 50% by weight. Combining monomers with 4 or more radically polymerizable double bonds exhibits excellent chemical resistance such as acid resistance and alkali resistance. In addition, for monomers having four or more radically polymerizable double bonds, in order to further enhance the above-mentioned effect, it is preferable that the molecular weight of each functional group is between 30 and 200. The reason for this is not clear, but it is considered to be due to a high degree of three-dimensional interaction. caused by the connection.

A monomer having 1 to 2 polymerizable double bonds in 1 molecule can also be used within the range that does not impair the effect of the present invention. For example, styrene, α-methylstyrene, acrylic esters such as methyl acrylate, methacrylates such as methyl methacrylate, acrylonitrile, acrylonitrile, vinyl acetate, vinyl propionate, ethylene glycol Alcohol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, neopentyl glycol diacrylate, 1,6- Hexylene glycol diacrylate, divinylbenzene, etc. One or a mixture of more than one of them can be used. The amount used is between 0.1 parts by weight and 10 parts by weight relative to 100 parts by weight of the metal pigment. If the amount used exceeds 10 parts by weight, the effect of the invention, that is, when the obtained resin-coated metal pigment is used to form a metal coating film, the characteristics will decrease, and the heat resistance stability of the metal pigment will also decrease, making it difficult to use it for practical use. The resin-coated metal pigment of the present invention is obtained by the following method: firstly disperse the untreated metal pigment in an organic solvent, then add (A) to treat the surface of the metal pigment while heating and stirring, and (A) It is at least one selected from free radical polymerizable unsaturated carboxylic acid, phosphoric acid with free radical polymerizable double bond, mono- or diester of phosphonic acid, and a coupling agent with free radical polymerizable double bond; then Slowly and continuously add at least one of (B) and (C), wherein (B) is a monomer with more than 3 radically polymerizable double bonds, and wherein (C) is a polymerization initiator while polymerizing, thereby A resin layer is formed on the surface of the metallic pigment.

Firstly, after dispersing the untreated metal pigment in an organic solvent, heat while stirring, and add (A) for treatment at the same time, although it is not particularly limited, the weight concentration of the metal pigment in the organic solvent is preferably 1 to 30%. . If it is less than 1%, uniform dispersion is possible, but the amount of solvent to be treated is too large and the subsequent removal process is laborious, which is not preferable. If it exceeds 30%, the dispersion of the metallic pigment tends to become non-uniform, which is also not preferable. In addition, the preferred temperature of this treatment is 40° C. to 150° C., and the time range is 5 minutes to 10 hours. When it is lower than 40°C, it will take additional time to raise the temperature to the polymerization temperature of (B). When it is higher than 150°C, the problem of easy ignition of organic solvent vapor must be seriously considered, which is not preferred. In addition, if the treatment time is less than 5 minutes, the diffusion of (A) tends to be insufficient, and if it exceeds 10 hours, the effect will not increase and it will only take time, which is not preferable.

Then, while slowly and continuously adding (B): a monomer having 3 or more radically polymerizable double bonds and (C): at least one of a polymerization initiator, polymerization is carried out to form a resin on the surface of the metallic pigment. layer. In the present invention, it is important to continuously add at least one of (B) and (C). Specifically, (B) and (C) can be added slowly at the same time, or (C) can be added first, then (B) can be added slowly, or (B) can be added first, and then (C) can be added slowly, any method is acceptable. Can. In the present invention, it is believed that by continuously adding at least one of (B) and (C) to carry out polymerization, a three-dimensional highly crosslinked resin layer can be formed on the metal surface. The polymerization temperature is not particularly limited, but it is preferably 60°C to 150°C. In order to increase the polymerization efficiency, it is desirable to carry out under an inert atmosphere such as nitrogen or helium. In addition, when adding continuously, it is preferable to dilute (B) and (C) with an organic solvent, etc., and then use a quantitative feeding pump to feed at a certain speed. The feeding time, that is, the additional addition time, is preferably more than 20% of the polymerization time. The polymerization time is not particularly limited, and is in the range of 2 hours to 10 hours. Here, the polymerization time refers to the time from the simultaneous presence of (B) and (C) in the reaction system to the time when the unreacted substance of (B) is less than 1%. When the feeding time is less than 20% of the polymerization time, the effect of continuous addition is small, which is not preferable. In addition, in order to reduce the reaction time, the feeding time is preferably 90% or less of the polymerization time, and in order to further shorten the reaction time and improve productivity, it is desirably 70% or less.

Compared with the metal pigment before treatment, the metal pigment coated with resin obtained in the present invention has an increased specific surface area, but compared with the metal pigment coated resin prepared by the existing method, it is characterized in that the specific surface area increases. It is greatly reduced, and the oil absorption is also reduced. The reason is considered to be due to the relatively uniform resin layer formed on the metal surface and the formation of a high degree of three-dimensional crosslinking. The coating film of the metal pigment coated with resin of the present invention exhibits excellent chemical resistance, gloss, and corrosion resistance. climatic properties.

In the present invention, the organic solvent used during polymerization can be aliphatic hydrocarbons such as hexane, heptane, pentane, mineral spirits, aromatic hydrocarbons such as benzene, toluene, xylene, solvent naphtha, tetrahydrofuran, diethyl ether, etc. Ethers, ethyl acetate, butyl acetate and other esters.

The polymerization initiator used in the present invention is a generally known free radical generator, including peroxides such as benzoyl peroxide, lauroyl peroxide, two-(4-tert-butylcyclohexyl) peroxycarbonate, and Azo compounds such as 2,2'-azobisisobutyronitrile and 2,2'-azobis-2,4-dimethylvaleronitrile. The amount used is not particularly limited in the present invention, and is 0.1 to 50 parts by weight relative to 100 parts by weight of the monomer having three or more radically polymerizable double bonds.

When the resin-coated metallic pigment of the present invention is used in paint, its coating film exhibits extremely excellent alkali resistance characteristics. This is considered to be due to the highly three-dimensional cross-linked resin layer coated on the surface of the metallic pigment, even if the alkali invades the inside of the coating film, it is difficult to reach the surface of the metallic pigment. As shown in the examples of the present invention, alkali-resistant The value is 0.01 to 2.0.

The metal paint of the present invention can be used as a solvent-based paint or a water-based paint, and mainly contains three basic components, namely (a) resin for paint, (b) metal pigment coated with resin, and (c) diluent.

As the coating resin for solvent-based coatings, any coating resins used in existing metal coatings can be used, such as acrylic resins, alkyd resins, oil-free alkyd resins, vinyl chloride resins, polyurethane resins, melamine resins, unsaturated poly Ester resins, urea resins, cellulose-type resins, epoxy resins, fluororesins, etc., may be used alone or in combination.

The preferred amount of the resin-coated metallic pigment used in the solvent-based paint is preferably 0.1 to 100 parts by weight, more preferably 1 to 50 parts by weight, based on 100 parts by weight of the paint resin. When the metal pigment of the coating resin is less than 0.1 parts by weight, the necessary metallic luster as a metal paint is insufficient. When using more than 100 parts by weight, the amount of metal pigment in the paint is too much, the coating workability is poor, and the quality of the coating film is not good. Good, not practical.

As diluents for solvent-based paints, there are aromatic compounds such as toluene and xylene, aliphatic compounds such as hexane, heptane and octane, alcohols such as ethanol and butanol, esters such as ethyl acetate and butyl acetate, Ketones such as butanone, chlorides such as trichloroethane, cellosolves such as ethylene glycol monoethyl ether, these diluents can be used alone or in combination of two or more. Its composition should be determined after considering the solubility to resin for coatings, coating film formation characteristics, coating workability, and the like.

Pigments, dyes, wetting agents, dispersants, anti-segregation agents, leveling agents, slip agents, anti-skinning agents, anti-gelling agents, defoaming agents and other additives generally used in the coatings industry can be added to solvent-based coatings.

The pigments of the present invention can also be used in water-based paints by using resins for water-based paints, which may be water-soluble resins or water-dispersible resins, which may be used alone or in admixture. The types can vary depending on the purpose and use, and there is no special limitation. Generally, there are acrylic type, acrylic-melamine type, polyester type, polyurethane type and other water-based coating resins, among which acrylic-melamine type is the most commonly used .

The amount of metallic pigment used in the coating resin used in the water-based paint is 0.1 to 100 parts by weight relative to 100 parts by weight of the resin for paint. Especially preferably, it is 1 weight part - 50 weight part. When the metal pigment of the coating resin is less than 0.1 parts by weight, the necessary metallic luster as a metal paint is insufficient. When using more than 100 parts by weight, the amount of metal pigment in the paint is too much, the coating workability is poor, and the quality of the coating film is not good. Good, not practical.

In addition, various additives commonly used in this field, such as dispersants, thickeners, anti-drip agents, anti-fungal agents, ultraviolet absorbers, film-forming aids, surfactants, other organic solvents, water, etc., It can be added arbitrarily as long as its type and amount do not impair the effect of the present invention.

The metal coatings referred to in the present invention can also be other commonly used coatings, such as powder coatings, in addition to solvent-based coatings and water-based coatings.

Hereinafter, examples of the present invention are given, but the present invention is not limited by these examples. In addition, the test method and measurement method used in this Example are as follows.

(1) Production of coated panels for evaluation

Use the aluminum paste coated with resin, and prepare the metal coating for evaluating alkali resistance according to the coating ratio shown in Table 1.

Table 1 Coating ratio (parts by weight) Aluminum paste coated with resin (converted to non-volatile content) 9 Thinner*1 40 Acrylic resin *2 100 Nitrocellulose resin solution*3 50

*1 Butyl acetate (30 parts), toluene (45 parts), isopropanol (20 parts),

A mixture of ethyl cellosol (5 parts)

*2 ACRYDIC A-166 (non-volatile components: 45%) (large

Manufactured by Nippon Ink Chemical Co., Ltd., normal dry type acrylic resin)

*3 LIG 1/2 (non-volatile components: 70%)

(Manufactured by Asahi Kasei Industry Co., Ltd., industrial nitrocellulose) dilute

 Release agent*1 is a solution with 16% non-volatile components

The viscosity of the coating was adjusted to 13 seconds (FC#4, 20°C) with the diluent listed in the above table, and sprayed on the ABS resin board until the film thickness was 10μ. After that, it was dried at 50° C. for 30 minutes to prepare a coated panel for evaluation.

(2) Determination of alkali resistance

The lower half of the above-mentioned coated plate was immersed in a beaker filled with 2.5N NaOH aqueous solution, and placed at 20°C for 24 hours. After the test, wash and dry the coated plate, measure the color of the impregnated part and the non-impregnated part according to the condition d (8-d method) of JIS-Z-8722 (1982), and measure the color according to 6.3. 2 Find the color difference ΔE.

(3) Gloss retention

The 60-degree gloss of the above-mentioned coated board was measured with a gloss meter (both the incident angle and the reflection angle are 60 degrees). Taking the 60-degree gloss of the untreated aluminum paste as G, and the 60-degree gloss of the resin-coated aluminum paste as G', the gloss retention rate R was obtained according to the following formula.

R＝(G′/G)×100

(4) Oil absorption

The resin-coated aluminum paste was heat-treated at 105°C for 3 hours to obtain a sample, which was measured with dibutyl phthalate according to JIS K 6221-1982 B method (scratch knife method).

(5) specific surface area

The solvent of the aluminum paste was removed by substitution with acetone to make the sample into a powder, and the specific surface area of the powdered sample was measured with a BET 1-point specific surface area meter (Shimadzu FLOW SORB2300).

Example 1

Add 75 grams of aluminum paste (MG-51 manufactured by Asahi Kasei Kogyo Co., Ltd., 67% metal content) and 300 grams of mineral spirits into a four-neck bottle with a capacity of 1 liter, stir under nitrogen, and raise the internal temperature to 80°C. Then 0.375 g of acrylic acid was added and stirring was continued for 30 minutes at 80°C. After that, 2.5 grams of trimethylolpropane trimethacrylate and 1.0 grams of di-trimethylolpropane tetraacrylate (each functional group molecular weight 116.5) and 0.35 grams of 2,2'-azobis-2,4 -Dimethylvaleronitrile was dissolved in 19 grams of mineral spirits, and the solution was added to the reaction system at a rate of about 0.13 g/min with a quantitative pump, and the addition was completed in 3 hours. Then, the internal temperature of the system was kept at 80° C., and the polymerization time was totaled 6 hours. At this time, a sample was taken, and the unreacted amount of trimethylolpropane trimethacrylate in the filtrate was measured by gas chromatography, and 99.5% or more of the added amount had reacted. After the polymerization is completed, the muddy reaction solution is filtered to obtain an aluminum paste coated with resin. The non-volatile component content (in accordance with JIS-K-5910) of this aluminum paste was 65.0 weight%. The amount of the coating resin was 8.3 parts by weight with respect to 100 parts by weight of the aluminum metal component. From this result, it can be deduced that acrylic acid, trimethylolpropane trimethacrylate, di-trimethylolpropane tetraacrylate, 2,2'-azobis-2,4-dimethylvaleronitrile have been More than 98% adhere to the aluminum surface.

Example 2

Except that trimethylolpropane trimethacrylate and di-trimethylolpropane tetraacrylate used in Example 1 were replaced with 3.5 grams of trimethylolpropane trimethacrylate, the same as in Example 1 Aluminum paste coated with resin is obtained by method.

Example 3

Add 75 grams of aluminum paste (MG-51 manufactured by Asahi Kasei Kogyo Co., Ltd., metal component ratio 67%) and 300 grams of mineral spirits into a four-necked bottle with a volume of 1 liter, stir under nitrogen, and raise the internal temperature to 60 ° C. Then 0.375 g of acrylic acid was added and stirring was continued for 30 minutes at 60°C. Then, 6.4 g of trimethylolpropane triacrylate and 1.6 g of di-pentaerythritol hexaacrylate (each functional group molecular weight 96.3) were dispersed in the reaction system. Then 0.8 grams of 2,2'-azobis-2,4-dimethylvaleronitrile was dissolved in 19 grams of mineral spirits, and the solution was added to the reaction system with a quantitative pump at a speed of about 0.08 grams/minute, 4 Hours added. The internal temperature of the system was kept at 60° C., and the total polymerization time was 7 hours. After the polymerization is completed, the slurry reaction solution is filtered to obtain a resin-coated aluminum paste. The non-volatile component content (in accordance with JIS-K-5910) of this aluminum paste was 60.0 weight%. The amount of the coating resin was 18.2 parts by weight relative to 100 parts by weight of the aluminum metal component. From this result, it can be inferred that more than 99% of acrylic acid, trimethylolpropane triacrylate, di-pentaerythritol hexaacrylate, and 2,2'-azobis-2,4-dimethylvaleronitrile have been attached to aluminum On the surface.

Example 4

Add 75 grams of aluminum paste (MG-51 manufactured by Asahi Kasei Kogyo Co., Ltd., 67% metal content) and 300 grams of mineral spirits into a four-neck bottle with a capacity of 1 liter, stir under nitrogen, and raise the internal temperature to 70°C. Then 0.4 g of acrylic acid was added and stirring was continued for 30 minutes at 80°C. Afterwards, 0.5 gram of 1,6-hexanediol diacrylate, 3.0 gram of trimethylolpropane trimethacrylate, 1.5 gram of pentaerythritol tetraacrylate (each functional group molecular weight 88) and 0.5 gram of azobisisobutyronitrile were dissolved in In 38 grams of mineral spirits, the solution was added to the reaction system with a quantitative pump at a speed of about 0.24 g/min, and the addition was completed in 3 hours. The internal temperature of the system was kept at 80° C., and the total polymerization time was 6 hours. After the polymerization is completed, the slurry reaction solution is filtered to obtain a resin-coated aluminum paste. The non-volatile content (in accordance with JIS-K-5910) of this aluminum paste was 62.0% by weight. The amount of the coating resin was 11.6 parts by weight relative to 100 parts by weight of the aluminum metal component. From this result, it can be deduced that more than 98% of acrylic acid, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate and 2,2'-azobisisobutyronitrile have been attached. on aluminum surfaces.

Example 5

Except that the amount of trimethylolpropane trimethacrylate used in embodiment 1 is changed to 1.0 gram, and the amount of di-trimethylolpropane tetraacrylate is changed to 2.5 grams, the coating resin is obtained in the same way as in embodiment 1 aluminum paste. The non-volatile content (in accordance with JIS-K-5910) of this aluminum paste was 60.0%.

Example 6

In addition to changing the amount of trimethylolpropane trimethacrylate used to 2.5 grams, the amount of di-trimethylolpropane tetraacrylate to 1.0 grams, and 0.35 grams of 2,2'-azobis-2 , the solution that 4-dimethylvaleronitrile is dissolved in 19 grams of mineral spirits adds outside in 1.2 hours with the quantitative pump with the speed of about 0.32 gram/min, obtains the coating resin by the same method of embodiment 1 aluminum paste. The non-volatile content (in accordance with JIS-K-5910) of this aluminum paste was 65.0%.

Example 7

150 g of aluminum paste (MG-51 manufactured by Asahi Kasei Kogyo Co., Ltd., 67% metal content) and 600 g of 2-propanol were added to a four-necked bottle with a capacity of 2 liters, stirred under nitrogen, and the inner temperature was raised to 70° C. Then add 7 grams of vinyltrimethoxysilane and 7 grams of purified water, and stir for 5 hours. Afterwards, filter the muddy reaction solution and wash carefully with mineral spirits. Add 75 grams of the aluminum paste thus obtained and 300 grams of mineral spirits into a four-necked bottle with a capacity of 1 liter, stir under nitrogen, and raise the inner temperature to 80° C. Afterwards, 2.5 g of trimethylolpropane trimethacrylate, 1.0 g of di-trimethylolpropane tetraacrylate, and 0.35 g of 2,2'-azobis-2,4-dimethylvaleronitrile Dissolve in 19 grams of mineral spirits, and add the solution to the reaction system at a rate of about 0.13 g/min with a quantitative pump, and complete the addition in 3 hours. The internal temperature of the system was kept at 80° C., and the total polymerization time was 6 hours. After the polymerization is completed, the slurry reaction solution is filtered to obtain a resin-coated aluminum paste. The non-volatile component content (in accordance with JIS-K-5910) of this aluminum paste was 65.0 weight%. The amount of the coating resin was 8.3 parts by weight relative to 100 parts by weight of the aluminum metal component. From these results, it can be inferred that vinyltrimethoxysilane, trimethylolpropane trimethacrylate, di-trimethylolpropane tetraacrylate, 2,2′-azobis-2,4-dimethyl More than 98% of valeronitrile has been attached to the aluminum surface.

Example 8

Except that acrylic acid was replaced by 2-methacryloyloxyethyl acid phosphate (manufactured by Daihachi Chemical Co., Ltd., MR-200), aluminum paste coated with resin was obtained in the same manner as in Example 1. The non-volatile component content (in accordance with JIS-K-5910) of this aluminum paste was 65.0 weight%. From these results, it can be deduced that 2-methacryloxyethyl acid phosphate, trimethylolpropane trimethacrylate, di-trimethylolpropane tetraacrylate, 2,2′-azobis -2,4-Dimethylvaleronitrile has more than 98% attached to the aluminum surface. Comparative example 1

The resin-coated aluminum paste was prepared in the same manner as in Example 1, except that the continuous addition of the feed pump was not performed, but the monomer (B) and the polymerization initiator were added together. Comparative example 2

The resin-coated aluminum paste was prepared in the same way as in Example 2, except that the continuous additional addition operation was not carried out through the feeding pump, but the monomer (B) and the polymerization initiator were added together. Comparative example 3

In addition to dissolving 2.5 g of trimethylolpropane trimethacrylate, 1.0 g of di-trimethylolpropane tetraacrylate and 0.35 g of 2,2′-azobis-2,4-dimethylvaleronitrile in In 19 grams of mineral spirits, add with the speed of about 0.76 gram/minute with quantitative pump, except that 0.5 hour adds, the aluminum paste of coating resin is obtained by the same method of embodiment 1. The non-volatile content (in accordance with JIS-K-5910) of this aluminum paste was 60.0%. Comparative example 4

In addition to replacing acrylic acid with a mixture of 0.88 grams of vinyltrimethoxysilane, 0.06 grams of phosphoric acid, 0.06 grams of water, and 1.00 grams of 2-butanol, trimethylolpropane trimethacrylate and bis-trimethylol Propane tetraacrylate was replaced with 3.5 grams of trimethylolpropane trimethacrylate, and the solution obtained by dissolving trimethylolpropane trimethacrylate in 19 grams of mineral spirits was passed through a quantitative pump at a rate of about 0.78 g/min. Add at a speed of 0.5 hour, except that 0.5 hour has added, the aluminum paste that coats resin is obtained by the same method of embodiment 1. The non-volatile content (in accordance with JIS-K-5910) of this aluminum paste was 60.0%. Comparative Example 5

Except that the operation of continuous additional addition by the quantitative pump was not carried out, but the solution obtained by dissolving trimethylolpropane trimethacrylate in mineral spirits was added at one time, the coating resin was prepared in the same way as in Comparative Example 4 aluminum paste. The non-volatile content (in accordance with JIS-K-5910) of this aluminum paste was 60.0%.

The properties of the aluminum pastes obtained in Examples 1-8 and Comparative Examples 1-5 are shown in Table 2.

In Table 2, the compounding ratio of the polyfunctional monomer represents the ratio (weight Compare).

Table 2 Aluminum Paste Properties Compounding ratio of multifunctional monomer*1% Feeding time*2(%) Oil absorption (g/g) Storage stability in water-based paints*3 Alkali resistance ΔE (8-d method) Gloss retention (%) Example 1 29 50 1.42 ○ 0.7 91 Example 2 0 50 1.61 ○ 1.7 90 Example 3 20 57 1.56 ○ 0.2 90 Example 4 33 50 1.45 ○ 0.3 90 Example 5 71 50 1.70 ○ 2.0 89 Example 6 29 20 1.60 ○ 1.0 90 Example 7 29 50 1.31 ○ 0.2 92 Example 8 29 50 1.41 ○ 0.6 90 Comparative example 1 29 0 1.82 x 2.5 88 Comparative example 2 0 0 1.90 x 3.0 85 Comparative example 3 29 8 1.84 x 2.3 88 Comparative example 4 0 7 1.44 ○ 15.0 88 Comparative Example 5 0 0 1.44 ○ 17.0 88

*1 A monomer with 4 or more radically polymerizable double bonds

*2 The percentage of the addition time of component (B) and/or component (C) to the polymerization time

*3 Storage stability in water-based paints

○: The amount of gas generated is 10 ml/g or less

×: The amount of gas generated is 10 ml/g or more

Example 9

Using the resin-coated aluminum paste obtained in Example 1, the resin-coated aluminum paste obtained in Comparative Example 2, the aluminum paste without resin-coated treatment (MG-51: manufactured by Asahi Kasei Industries, Ltd.), and the fluororesin, according to After the coating ratio in Table 3 was prepared, the coating was applied on an aluminum plate (1×70×150 mm) by air spraying to make a film thickness of 30 μ. Then, it was dried at 100° C. for 30 minutes to form a fluororesin type metal coating film.

Table 3 Coating ratio (parts by weight) LUM IFURON LF 200 ^*1 100 Aluminum paste (based on 100% non-volatile components) 10.2 DURANATE TPA-100 ^*2 7.8 Thinner ^*3 150 Total 268.0

*1...Manufactured by Asahi Glass Co., Ltd.

*2…Manufactured by Asahi Kasei Industries, Ltd.

*3...toluene/xylene/ethyl acetate/butyl acetate

Weight ratio = 30/20/20/30

The metal coating film was subjected to a spot test for chemical resistance at 20° C. for 10 days, and then the degree of discoloration of the coating film was evaluated. In addition, a 3000-hour exposure test was performed with the same coating film using a sunshine weather meter (Sunshine etherometer, SWOM). The chemicals used in the chemical resistance test are aqueous solutions of 10% hydrochloric acid, 10% NaOH, and 10% sulfuric acid. The results are shown in Table 4.

Table 4 Evaluation of the degree of discoloration of the coating film Types of Aluminum Paste The degree of discoloration of the coating film 10% hydrochloric acid spot test 10% NaOH spot test 10% sulfuric acid spot test Sunshine climate meter test Resin-coated aluminum paste of Example 1 ○ ○ ○ ○ Resin-coated aluminum paste of Comparative Example 2 △ △ ○ △ MG-51 (untreated aluminum paste) x x x △

○: No discoloration

          △: slight discoloration

      ×: Obvious discoloration

As can be seen from the above table, the coating film using the resin-coated aluminum paste of Example 1 of the present invention did not change at all in the chemical resistance test. Moreover, in the test with the sunshine climate meter, the coating film using the resin-coated aluminum paste of Example 1 of the present invention has almost no change in the appearance of the coating film, showing excellent weather resistance.

Example 10

According to the coating ratio in Table 5, after using 1,1-difluoroethylene type fluororesin to make a resin type coating, apply it on an aluminum plate with a rod coater to make the film thickness 30μ, and then dry it at 240°C for 5 minutes , to make a coating film. The same chemical resistance spot test as in Example 9 was carried out. As a result, the coating film using the resin-coated aluminum paste of Example 1 exhibited extremely excellent chemical resistance as in Example 9.

Table 5 Coating ratio (parts by weight) Paraloid B-44 ^*1 15.2 Aluminum paste (based on 100% non-volatile components) 9.2 Thinner ^*2 120 NEOFLON VDF VP-850 ^*3 45.6 Total 190.0

*1…Manufactured by Rohm and Haas

*2…Isophorone/Dimethylphthalate/Toluene/Isobutyl Acetate/Acetic Acid

The weight ratio of ethyl ester = 45/24/15/8/8

*3…Manufactured by Daikin Industries

Example 11

After the aluminum paste coated with resin obtained in Example 1 and the aluminum paste coated with resin obtained in Comparative Example 2 were made into coatings according to the coating ratio in Table 6, they were coated on On an ABS resin plate, the film thickness was 30 µ. Then after drying at room temperature for 24 hours, measure the 60-degree gloss of the coating film. As a result, it can be seen that the coating gloss of the aluminum paste coated with resin obtained in Example 1 is a high value of 65%. The coating film gloss of the resin-coated aluminum paste was 53%.

Table 6 Coating ratio (parts by weight) ACRYDIC A-801 ^*1 100 Aluminum paste (based on 100% non-volatile components) 5 DURANATE TPA-100 16.2 Thinner ^*2 120 Catalyst (dibutyl dilaurate) 1.0 Total 242.2

*1...Manufactured by Dainippon Ink Chemical Co., Ltd.

*2...of ethyl acetate/butyl acetate/toluene/xylene/methoxypropyl acetate

Weight ratio = 20/30/30/15/5

Example 12

The resin-coated aluminum pastes obtained in Examples 1-8 and Comparative Examples 1-5 were formulated according to Table 7 to make water-based paints, and their storage stability was evaluated. Add 100 grams of the above-mentioned paints to 200 ml Erlenmeyer flasks, and seal them with rubber stoppers with graduated pipettes. The state of gas production after standing at 50°C for 24 hours is shown in Table 2 above. The resin-coated aluminum paste obtained in Example 1 was made into a water-based paint according to the proportions in Table 7, and was applied on an aluminum plate by air spraying to make a film thickness of 30 μ. Then, after drying at 170° C. for 20 minutes, a coating film was prepared, and a coating film with excellent metallic feeling was obtained.

Table 7 Coating ratio (parts by weight) Metallic components of resin-coated metallic pigments 2821 Water-soluble acrylic resin (residue after heating = 50%) ^*1 370 Water-soluble melamine resin (residue after heating = 50%) ^*2 100 pure water 491 Total 3782

*1...ALM ATEXWA-911 (manufactured by Mitsui Topress Chemical Co., Ltd.)

Add dimethylethanolamine to adjust the pH to 9.5

*2...CYMEL 350 (manufactured by Mitsui CYTEC Co., Ltd.)

Example 13

The specific surface areas of the resin-coated aluminum paste obtained in Example 1, the resin-coated aluminum paste obtained in Comparative Example 2, and the aluminum paste not treated with resin coating (MG-51: manufactured by Asahi Kasei Industries, Ltd.) were measured. The results are shown in Table 8. The specific surface area of the aluminum paste coated with resin obtained in Example 1 is 1.9 times that of the aluminum paste coated with resin without coating resin, and the specific surface area of the aluminum paste coated with resin obtained in Comparative Example 2 is 1.9 times that of the aluminum paste coated with resin without coating resin. 3.0 times that of the paste, it can be seen from the results that the resin-coated aluminum paste obtained in Example 1 is coated with a highly three-dimensional cross-linked resin.

Table 8 specific surface area

Example 14

Except that the aluminum paste used in Example 1 was replaced by MH-8801 (manufactured by Asahi Kasei Industry Co., Ltd., with a metal content of 65%), the resin-coated aluminum paste was prepared in the same manner as in Example 1. The alkali resistance of the obtained resin-coated aluminum paste was measured, and the color difference ΔE=0.3, showing excellent alkali resistance. Comparative example 6

Except that the aluminum paste used in Comparative Example 2 was changed to MH-8801 (manufactured by Asahi Kasei Industry Co., Ltd., metal component content 65%), the aluminum paste coated with resin was made in the same way as Comparative Example 2. The alkali resistance of the obtained resin-coated aluminum paste was measured, and the color difference ΔE=3.1.

Example 15

The specific surface areas of the resin-coated aluminum paste obtained in Example 14, the resin-coated aluminum paste obtained in Comparative Example 6, and the aluminum paste not treated with resin coating (MH-8801: manufactured by Asahi Kasei Industries, Ltd.) were measured. The results are shown in Table 9. The specific surface area of the aluminum paste coated with resin obtained in Example 14 is 1.5 times that of the aluminum paste coated with resin without coating, and the specific surface area of the aluminum paste coated with resin obtained in Comparative Example 6 is 1.5 times that of the aluminum paste processed without coating. 3.0 times of that, it can be seen from the results that the resin-coated aluminum paste obtained in Example 13 is coated with a highly three-dimensional cross-linked resin.

比较例6     28.5     3.0 MH-8801     9.5     - Table 9 specific surface area

Comparative Example 6 28.5 3.0 MH-8801 9.5 -

The resin-coated metallic pigment of the present invention is coated with a resin having a high crosslink density, so it has excellent chemical resistance, weather resistance and storage stability. In addition, the specific surface area is small, the oil absorption is small, and the gloss reduction caused by coating resin can be suppressed to a minimum.

For the above reasons, the resin-coated metallic pigments of the present invention are suitable for use in metallic paints, printing inks, blending into plastics.

In addition, since the metal coating of the present invention has excellent weather resistance, it is suitable for parts such as automobile bodies, bumpers, and side mirrors with durability requirements, exterior decoration of buildings such as veneers, roofs, and walls, and home appliances. and other fields.

Claims (9)

1, a kind of metallic pigment of application of resin, it is characterized in that, use following (A), (B), (C) three kinds of raw materials, wherein (A) is from free-radical polymerised unsaturated carboxylic acid, and/or have the monoesters or a diester of the Phosphoric acid or phosphonic acid of free-radical polymerised pair of key, and/or have select in the coupler of free-radical polymerised pair of key at least a, (B) for having the monomer of free-radical polymerised pair of key more than 3, (C) be polymerization starter, at first adding (A) handles after the metallic pigment, with (B) with (C) at least aly slowly append adding, form the polymeric resin layer in the metallic surface

Wherein, the consumption of the free-radical polymerised unsaturated carboxylic acid (A) is 0.01～10 weight part with respect to 100 weight part metallic pigment, having the monoesters of Phosphoric acid or phosphonic acid of free-radical polymerised pair of key or the consumption of diester is 0.01～30 weight part with respect to 100 weight part metallic pigment, the consumption that has the coupler of free-radical polymerised pair of key is 0.01～30 weight part with respect to 100 weight part metallic pigment, and the consumption that has the coupler of free-radical polymerised pair of key is 0.01～20 weight part with respect to 100 weight part metallic pigment; (B) consumption is 2～50 weight parts with respect to metal ingredient 100 weight parts of metallic pigment; (C) consumption is 0.1～50 weight part with respect to the monomer that 100 weight parts have free-radical polymerised pair of key more than 3.

2, according to the metallic pigment of the application of resin of claim 1 record, it is characterized in that, as the monomer that has free-radical polymerised pair of key more than 3 of (B) is the monomer and the monomeric miscellany that has free-radical polymerised pair of key more than 4 that has 3 free-radical polymerised pair of keys, has wherein that the monomeric weight ratio of free-radical polymerised pair of key is 10～60% more than 4.

3, according to the metallic pigment of the application of resin of claim 1 record, it is characterized in that, (B) with (C) at least a joining day of appending be more than 20% of polymerization time.

4, according to the metallic pigment of the application of resin of claim 2 record, it is characterized in that, (B) with (C) at least a joining day of appending be more than 20% of polymerization time.

According to the metallic pigment of the application of resin of claim 1 record, it is characterized in that 5, the molecular weight that has monomeric each functional group of free-radical polymerised pair of key more than 4 is more than 30 below 200.

According to the metallic pigment of the application of resin of claim 2 record, it is characterized in that 6, the molecular weight that has monomeric each functional group of free-radical polymerised pair of key more than 4 is more than 30 below 200.

According to the metallic pigment of the application of resin of claim 3 record, it is characterized in that 7, the molecular weight that has monomeric each functional group of free-radical polymerised pair of key more than 4 is more than 30 below 200.

According to the metallic pigment of the application of resin of claim 4 record, it is characterized in that 8, the molecular weight that has monomeric each functional group of free-radical polymerised pair of key more than 4 is more than 30 below 200.

9, the metallic paint that contains the metallic pigment of the application of resin of each record in the claim 1 to 8.