JPH06128532A - Paint composition - Google Patents

Abstract

(57) [Summary] [Structure] Acrylic copolymer containing hydroxyl group and / or carboxyl group, and film-forming components typified by alkyd resin, oil-free alkyd resin and / or urethane resin; aluminum powder, copper powder Pigments such as zinc powder and other inorganic powders and / or organic powders; the above film-forming components and the above pigments,
A coating composition comprising a fine particle polymer having a modified particle structure or a hollow particle structure, which is not miscible in a system composed of a solvent and can be stably dispersed; and a solvent as an essential component. Composition. [Effect] Above all, it has excellent curability, and
A highly practical cured coating that maintains high appearance and is excellent in weather resistance without causing various coating defects such as "sag", "repellency" and "pinhole". To give.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel and useful coating composition. More specifically, the present invention relates to a base coating composition containing, as essential components, a film-forming component, pigments, fine particle polymers, and solvents, and is mainly 2 coat coloring. The present invention relates to a coating composition useful as a colored coating material or a metallic base coating material used when forming a coating film.

[0002]

2. Description of the Related Art For example, as a method for coating an automobile body, a clear paint is applied on a base paint containing a coloring pigment or a metallic pigment by a wet-on-wet method (wet-on-wet method). The method of baking or hardening at room temperature is widely adopted.

The coating film obtained by such a method includes
For example, if the base paint and clear paint are mixed together, the arrangement of the metallic pigment in the base paint may become defective, or during baking, pinholes, craters, etc.
So-called coating film defects are easily induced.

As an approach to low-pollution paint,
What is being developed is a high-solids-type paint that reduces the amount of solvents used, or a water-based paint that should replace the solvent-based paint. Even when there is a defect, the above-mentioned defects are even more noticeable.

Therefore, in the past, the molecular weight of the base coating resin was increased, a different type of base coating resin from the clear coating resin was used, or the coating conditions were appropriately adjusted. Various methods have been adopted in which the miscibility of both coating resins is reduced by selecting, but each of these methods has drawbacks.

That is, in the case of the method (1), the coating non-volatile content of the paint is apt to be lowered, and in the case of the method (2),
There is a drawback that the adhesion between the resin for base paint and the resin for clear paint tends to be lowered, and in the case of such a method, there is a drawback that the coating efficiency is inevitably lowered.

[0007]

However, the present inventors have earnestly started research in order to solve and solve the above-mentioned various drawbacks and problems.

[0008] Therefore, the problem to be solved by the present invention is to provide a base coating composition which, in particular, has an excellent finished appearance without the above-mentioned drawbacks or problems.

[0009]

Therefore, the present inventors have
As a result of intensive and intensive studies, focusing on the problems to be solved by the invention as described above, as a result, a crosslinkable fine particle polymer having a hollow or irregular structure was added to a base coating material in a colored coating material or a metallic base coating material. The present invention has been completed by discovering that a coating film excellent in curability and weather resistance can be obtained while maintaining a high appearance by including it in the form of.

That is, the present invention basically comprises a film-forming component (A), a pigment (B), a film-forming component (A) and a pigment (B), and a solvent (D). ) Is not miscible in the system consisting of and is stable and can be stably dispersed, and contains fine particle polymers (C) having a modified particle structure or a hollow particle structure and the solvents (D) as essential components. To provide a coating composition comprising:

Specifically, for example, a specific film containing, as an essential component, a specific resin such as an alkyd resin, an oil-free alkyd resin, a urethane resin and / or an acrylic copolymer having a hydroxyl group or a carboxyl group. Forming component (A), aluminum powder,
Crosslinking that is substantially insoluble in the specific pigments (B) consisting of copper powder, zinc powder, inorganic powder and / or organic powder, and the above solvents (D) prepared by, for example, emulsion polymerization method. Fine particulate polymers (C) and these solvents (D
And to contain a coating composition as an essential component, and is intended to provide a coating composition,

100 parts by weight of the component (A), 4 to 470 parts by weight of the pigments (B), 0.1 to 100 parts by weight of the fine particle polymers (C), and an appropriate amount of the solvents (D). By providing a colored paint containing and as an essential component, the clear paint is applied by the wet-on-wet system without impairing the coating workability, and the curability and weather resistance are improved. An object of the present invention is to provide a base coating composition capable of obtaining a two-coat colored coating film excellent in various properties.

Here, first, the above-mentioned film-forming component (A) refers to one that can be baked or cured at room temperature, and only typical film-forming components are exemplified. For example, a mixture of a hydroxyl group-containing vinyl polymer and aminoplast; a mixture of at least one hydroxyl group-containing resin selected from the group consisting of alkyd resin, oil-free alkyd resin and urethane resin, and aminoplast;

Mixtures of hydroxyl group-containing vinyl polymers and isocyanate group-containing resins or isocyanate group-containing vinyl polymers; carboxyl group-containing vinyl polymers and epoxy resins or epoxy group-containing vinyl polymers. Mixtures with polymers; or carboxyl group-containing vinyl-based monomers, epoxy group-containing vinyl-based monomers and copolymers; or carboxyl group-containing vinyl-based polymers, and cyclocarbonate group-containing vinyl-based monomers Mixtures with polymers; or copolymers of carboxyl group-containing vinyl monomers and cyclocarbonate group-containing vinyl monomers.

Of the film-forming component (A), a hydroxyl group,
To prepare vinyl polymers having various functional groups such as a carboxyl group, an epoxy group or a cyclocarbonate group, functional group-containing monomers and other copolymerizable monomers can be prepared. The monomers may be copolymerized by a conventional method.

As only specific examples of such functional group-containing monomers, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) are listed. ) Acrylate, 2-hydroxybryl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, polyethylene glycol mono (meth) acrylate such as (meth) acrylic acid Various hydroxyalkyl esters;

Maleic anhydride, itaconic anhydride,
Various polymerizable unsaturated double bond (unsaturated bond) -containing hydroxyalkyl ester monoesters such as adducts of various acid anhydride group-containing monomers with various polyhydric alcohols such as ethylene glycol Carboxylic acids; various unsaturated bond-containing polyhydroxyalkyl esters such as dihydroxyalkyl esters of various polycarboxylic acids such as maleic acid, fumaric acid and itaconic acid; or various such as hydroxyalkyl vinyl ethers Hydroxyl-containing monomers of

Various unsaturated mono- or dicarboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid or various carboxyl group-containing units such as acid anhydrides as listed above. Various kinds of epoxy group-containing monomers such as glycidyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, vinylcyclohexene oxide, and glycidyl vinyl ether; or 2-oxo-1,3-dioxolane- Examples include various cyclocarbonate group-containing monomers such as 4-yl (meth) acrylate.

On the other hand, if only representative examples of other monomers copolymerizable with the functional group-containing monomers are given, methyl (meth) acrylate and ethyl (meth) acrylate are given. , N-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate; various (meth) acrylic acid esters; dimethyl maleate , Diethyl fumarate, di-n-butyl itaconate and the like diesters of polyhydric carboxylic acids as described above and monohydric alcohols;

Vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, "Veoba" (product of Shell Co. of the Netherlands); "Viscoat 8F, 8FM, 3F.
Or 3FM "[fluorine-containing (meth) acrylic monomers manufactured by Osaka Organic Chemical Industry Co., Ltd.], perfluorocyclohexyl (meth) acrylate, di-perfluorocyclohexyl fumarate, N-isopropyl perfluorooctane sulfone Vinyl esters containing perfluoroalkyl groups such as amidoethyl (meth) acrylate;

Various vinyl halides (vinylidene) such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride and chlorotrifluoroethylene; various α-olefins such as ethylene and propylene; styrene and α Various aromatic vinyl monomers such as -methylstyrene, p-tert-butylstyrene, o-methylstyrene, p-methylstyrene; (meth) acrylamide, N-alkoxymethylated (meth) acrylamide, diacetone ( Various carboxylic acid amide group-containing monomers such as (meth) acrylamide; Various sulfonic acid amide group-containing monomers such as p-styrenesulfonic acid amide and N, N-dimethyl-p-styrenesulfonamide ;

Various N, N-dialkylaminoalkyl (meth) acrylates such as N, N-dimethylaminoethyl (meth) acrylate and N, N-diethylaminoethyl (meth) acrylate, and acid anhydrides as listed above. Various adducts of group-containing monomers with compounds having an active hydrogen group capable of reacting with an acid anhydride group, such as N, N-dimethylaminopropylamine, and a tertiary amino group. Tertiary amino group-containing monomers; Various cyano group-containing monomers such as (meth) acrylonitrile;

Various kinds of (α, β-ethylenic) unsaturated carboxylic acids represented by hydroxyalkyl esters of (meth) acrylics as described above and a phosphoric acid or a phosphoric ester can be obtained by condensation reaction. Monomers containing phosphate bond; or 2-acrylamido-2-
Examples include various sulfonic acid group-containing monomers such as methyl-propane sulfonic acid or organic amine salts thereof.

To obtain the hydroxyl group-containing vinyl polymer, a known method such as a solution polymerization method, a bulk polymerization method, an emulsion polymerization method or a suspension polymerization method, and a solution pressure polymerization method are used. Although the method of 1) can be applied as it is, the solution radical polymerization method is the simplest.

As the solvents to be used at that time, only representative ones are exemplified, and various kinds of hydrocarbons such as toluene, xylene, cyclohexane, n-hexane, heptane and octane; methanol and isopropanol. , N-butanol, isobutanol, sec-
Various alcohols such as butanol and ethylene glycol monomethyl ether; methyl acetate, ethyl acetate,
Various esters such as -n-butyl acetate and amyl acetate;

Various ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl ketone, and cyclohexanone; or various amides such as dimethylformamide and dimethylacetamide, which may be used alone or in combination of two or more. Of course, they may be used in combination.

Polymerization may be carried out by a conventional method using such a solvent and various polymerization initiators such as azo type or peroxide type, and at that time, if necessary, As a molecular weight modifier, lauryl mercaptan,
Various known and conventional chain transfer agents such as octyl mercaptan, 2-mercaptoethanol or α-methylstyrene dimer can also be used.

In addition to the solution radical polymerization method described above, an ionic polymerization method is available as a method for preparing the functional group-containing vinyl polymers as described above. Polymers obtained by such an ionic polymerization method are also available. Further, in the present invention,
It can be used without any problems.

Next, the aforementioned aminoplast means melamine, urea, acetoguanamine, benzoguanamine,
Condensates obtained by reacting various amino group-containing compound components such as steroganamin or spiroguanamine with various aldehyde compound components such as formaldehyde, paraformaldehyde, acetaldehyde or glyoxal by a conventional method;

Alternatively, those obtained by partially or completely etherifying these condensates with alcohols, especially lower alcohols of C _{1 to} C ₄ are referred to. Specifically, it is methyl etherified melamine or isobutyl etherified melamine.
From the viewpoint of high solidification (high solidification), use of methyl etherified melamine is desirable.

Among the film-forming components (A), a method for preparing (condensed) polymers consisting of alkyd resin, oil-free alkyd resin or urethane resin will be described. First, each of these (condensed) polymers is In any case, as so-called synthesis conditions, well-known and commonly used means such as an esterification method can be applied as they are.

Here, the urethane resin refers to a resin having at least one urethane bond in one molecule, such as an isocyanate-modified acrylic resin, an isocyanate-modified alkyd resin, and an isocyanate-modified oil-free alkyd resin. However, the use of an isocyanate-modified alkyd resin and / or oil-free alkyd resin is desirable because of the ease of synthesis and the relatively low risk of gelation.

The urethane resin may be prepared by reacting an alkyd oligomer having one or more hydroxyl groups in one molecule with an organic diisocyanate compound to extend the molecular chain.

As the organic diisocyanate compound which can be used, only representative ones are exemplified. Various aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; xylylene diisocyanate and isophorone diisocyanate. , Various cycloaliphatic diisocyanates;

Or tolylene diisocyanate, 4,
Various aromatic diisocyanates such as 4′-diphenylmethane diisocyanate are used, and it is needless to say that they may be used alone or in combination of two or more, but from the viewpoint of yellowing resistance of the coating film, aliphatic diisocyanate is used. It is preferable to use a type of

Further, only representative polybasic acid components used in synthesizing the polyester component for the alkyd resin, oil-free alkyd resin or urethane resin will be exemplified, and terephthalic acid and isophthalic acid will be given. , Orthophthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid, hexahydroterephthalic acid, methylhexahydrophthalic acid, endomethylenetetrahydrophthalic acid , Methylendomethylenetetrahydrophthalic acid, maleic acid, fumaric acid, itaconic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, pimelic acid, suberic acid, sebacic acid,

Dimeric fatty acids, trimellitic acid, trimesic acid, pyromellitic acid, cyclopentanetetracarboxylic acid, alkyl esters of these, and reactive derivatives of these with anhydrides. ,
Preferably, if one or more of hexahydroterephthalic acid or various reactive derivatives thereof are used in an amount of 50 mol% or more in the total polybasic acid component, curability and weather resistance of the coating film are improved. In addition, it is possible to obtain a coating material excellent in terms of solubility and viscosity reduction.

On the other hand, as the polyhydric alcohol component used when synthesizing the polyester component for the alkyd resin, the oil-free alkyd resin and / or the urethane resin, ethylene glycol, Propylene glycol, trimethylene glycol, 1,4-butanediol, 1,3
-Butanediol, 1,5-pentanediol, 1,6
-Such as hexanediol, neopentyl glycol,
Various alkylene glycols;

Various aromatic or alicyclic glycols such as 1,4-cyclohexanedimethanol, bis-hydroxyethyl terephthalate, hydrogenated bisphenol A, and an alkylenoxide adduct of the hydrogenated bisphenol A. In addition, a monoepoxy compound can also be used in combination as the alcohol component, and various glycol components such as glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, and mannitol, as described above, can be used. And various polyester compounds such as adducts with .epsilon.-caprolactone can also be used.

From the viewpoint of the weather resistance of the coating film, good results can be obtained by using neopentyl glycol in an amount of 30 mol% or more of all alcohol components.

In addition, only specific examples of fatty acids used for preparing the alkyd resin are exemplified by octyl acid, palmitic acid, stearic acid, persatic acid, oleic acid, linoleic acid and linolenic acid. Begin,

C ₈ or more, such as coconut oil fatty acid, hydrogenated coconut oil fatty acid, tall oil fatty acid, castor oil fatty acid, dehydrated castor oil fatty acid, rice bran oil fatty acid, linseed oil fatty acid, soybean oil fatty acid, and safflower oil fatty acid. The long-chain saturated or unsaturated monobasic acids and the like should be appropriately selected and used in consideration of the solubility in solvents, the weather resistance of the coating film, the economical efficiency and the like.

A mixture of the alkyd resin, oil-free alkyd resin and / or urethane resin thus obtained and aminoplast as described above is also used as one of the film-forming components (A), and satisfactory results are obtained. give.

Further, as described above, a film-forming component containing a specific hydroxyl group-containing vinyl polymer and a film-forming component composed of a specific alkyd resin, oil-free alkyd resin and / or urethane resin, respectively. A mixture having an arbitrary ratio of
It is used as a kind of and gives satisfactory results.

Further, at least one hydroxyl group-containing polymer selected from the group consisting of the hydroxyl group-containing vinyl polymers, alkyd resins, oil-free alkyd resins and urethane resins listed above, and the amino group as described above. A co-condensate obtained by co-condensing a part or all of aminoplast with a hydroxyl group-containing polymer according to a conventional method using a mixture with a plast is also used as one of the film-forming components (A). And give satisfactory results.

Furthermore, such a cocondensate, at least one hydroxyl group-containing polymer selected from the group consisting of the above-mentioned hydroxyl group-containing vinyl polymers, alkyd resins and urethane resins, and aminoplast. Mixtures of and are likewise used as the film-forming component (A), giving satisfactory results.

As the above-mentioned pigments (B), any pigments that are usually used for paints can be applied, but among them, only typical ones will be exemplified. If it stays, various inorganic pigments such as titanium oxide and carbon black; quinacridone pigment,
Various organic pigments such as azo and phthalocyanine pigments; various metal powders such as aluminum powder, copper powder and zinc powder.

Of course, these pigments may be used alone or in combination of two or more kinds, and when the dispersibility of the pigments is poor, a suitable resin for dispersing the pigment may be prepared by a conventional method. Of course, it is possible to use it in various forms such as dispersing the pigments beforehand.

Among them, the amount of the above-mentioned pigments (B) used for coloring paints is 4 to 47 with respect to 100 parts by weight of the film-forming component (A).
An amount (ratio) that is 0 parts by weight is suitable.

On the other hand, as the top coating composition, since it is usually used in the form of a clear coating composition, it is not essential to use such pigments, but if necessary, various pigments as described above are used. There is no problem in using the kind.

By the way, in particular, when using the above-mentioned metal powders, a so-called two-coat metallic coating film is obtained, and when using inorganic and / or organic pigments, A so-called two-coat colored coating film having a more beautiful appearance than that of the enamel coating film is obtained.

Next, the above-mentioned fine particle polymers (C) are the above-mentioned film-forming component (A), the above-mentioned pigments (B),
It refers to polymers that are not miscible in a system comprising a solvent (D) as described below and can be stably dispersed, and mainly constitutes a colored coating material (A),
It is added to each of the mixtures comprising the components (B) and (D) in order to impart so-called pseudoplastic viscosity behavior.

The above-mentioned mixture of the components (A), (B) and (D) exhibits substantially Newtonian flow characteristics and has no yield value or an extremely small value. Therefore, for example, in the case where the coating work is performed with the substrate vertical, "saggling" is likely to occur due to the action of gravity and the temperature rise during baking performed after the coating;

Furthermore, since the (condensed) polymers in the film-forming component (A) for the base paint or the film-forming component for the top clear paint have a relatively small molecular weight, "repelling" Various coating film defects such as the occurrence of "pinholes" and "pinholes" tend to occur.

However, when the specific fine particle polymer (C) as shown below is added, the apparent viscosity during standing is increased, but a high shear stress is applied such as during spraying. In such a case, the viscosity becomes sufficiently small so that the spraying work can be performed without any difficulty, and the structure is already formed within a few seconds or a few minutes after the application to the substrate. The effect of preventing such coating defects, such as the occurrence of viscosity and the absence of coating defects such as "repellency" and "pinholes", will work sufficiently.

In the present invention, an aqueous emulsion or gelled fine particle polymers obtained by aqueous suspension polymerization are used as the fine particle polymer. Such gelled fine particle polymers are substantially non-swellable even in a solvent having a large polymer dissolving power such as toluene and ethyl acetate, and further, a resin solution or dispersion containing such a solvent having a large dissolving power. When added to the liquid,
Without increasing the viscosity of such resin (solution) dispersion,
It is possible to realize the acquisition of a dispersion liquid having a high resin content, and after drying, it is possible to form a solid resin composition together with the added resin solution or dispersion liquid, which has a high crosslinking density. It can be defined as a fine particle polymer having.

Examples of the method for preparing the gelled fine particle polymer are as follows. That is, 1 to 100% by weight of polyfunctional monomers, and monomers having one (α, β-ethylenic) unsaturated bond in one molecule,
That is, 0 to 97% by weight of the monofunctional monomer is 10
Organic and / or inorganic radical polymerization initiator having a half-life of 3 hours or less at a temperature of less than 0 ° C., that is, one or more low-temperature decomposition type initiators and a half-life at a temperature of 100 to 250 ° C. Using an organic radical polymerization initiator for 3 hours, that is, one or more high-temperature decomposition initiators,
First, there is a method of polymerizing in an aqueous emulsion or aqueous suspension state at a temperature of 20 ° C. or more and less than 100 ° C.

Here, if only representative examples of the above polyfunctional monomers are given, ethylene glycol di (meth) acrylate and total carbon number are 10
28 oligoethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolethane tri (meth) acrylate,
Poly (meth) acrylates of various polyhydric alcohols such as trimethylolpropane tri (meth) acrylate, glycerin tri (meth) acrylate, pentaerythritol tetra (meth) acrylate;

Esters of various allyl alcohols such as diallyl succinate, diallyl phthalate and triallyl isocyanurate; butadiene, pentadiene,
Dienes such as isoprene and chloroprene; or divinylbenzene or dicyclopentenyl (meth) acrylate, among which divinylbenzene, dicyclopentenyl (meth) acrylate, triallyl isocyanurate or polyhydric alcohol It is preferable to use poly (meth) acrylates.

As the monofunctional monomers, various monomers that are used when preparing the functional group-containing polymers can be applied as they are.

On the other hand, as the low temperature decomposition type initiator, various inorganic compounds such as potassium persulfate, ammonium persulfate or hydrogen peroxide; or acetyl peroxide, propionyl peroxide, isobutyryl peroxide, benzoyl peroxide, Various organic compounds such as tert-butyl peroxyoctoate or azobisisobutyronitrile are each particularly representative,

The high temperature decomposition type initiator is ter
Organic compounds such as t-butyl hydroperoxide, tert-butyl cumyl peroxide, tert hobutyl peroxybenzoate, di-tert-butyl peroxide, dicumyl peroxide or cumene hydroperoxide are particularly representative. It is a thing.

Further, as a method for preparing such irregularly shaped hollow particles, for example, a so-called seed polymerization method in which polymerization is carried out in two stages is generally used. At this time, in either the initial reaction or the two-step reaction, a hollow particle structure can be obtained by using monomers having an ionic functional group and performing phase separation by adjusting pH.

Here, if only representative examples of the ionic functional group-containing monomers are given, firstly, as those having an anionic property, N, N-
Dimethylaminoethyl (meth) acrylate, N, N-
Various N, N-dialkylaminoalkyl (meth) acrylates such as diethylaminoethyl (meth) acrylate; various tertiary amino group-containing monomers such as N, N-dimethylaminopropylamine. Then

Next, as those having a cationic property, various unsaturated mono- or dicarboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid, or acid anhydride groups as described above are used. Examples include contained monomers.

Also in this case, as the monomers to be copolymerized with the ionic functional group-containing monomers, the copolymerizable monomers as in the case of preparing the above vinyl polymer are used. Kinds can be used as well.

The above-mentioned polyfunctional monomers can be contained in both the initial reaction and the second step reaction.

As a method for preparing the gelled fine particle polymers, if the method described above is followed, the polymerization reaction is
Since it is carried out under a relatively mild condition of a temperature of 0 ° C. or more and less than 100 ° C., it is possible to prepare an aqueous emulsion or an aqueous suspension with a good yield even if a large amount of the above-mentioned polyfunctional monomers are used. I can.

In the polymerization reaction in the first step, various known and conventional emulsifiers and dispersion stabilizers can be appropriately used.

The gelled hollow fine particle polymers thus obtained have particles already formed by the initial polymerization reaction, so that they should be used in place of the second step polymerization reaction or as described above. In any case of the polymerization reaction in the drying step performed in the air or the inert gas, the agglomeration (blocking) due to the reaction between the fine particles does not occur.

Thus, the gelled hollow fine particle monomer in the aqueous emulsion or suspension obtained after various types of polymerization is evaporated or azeotroped with water,
They can be separated in the form of solids by physical or chemical means such as sedimentation or agglomeration of polymers (particles), or when such physical or chemical means are applied. In the presence of resins and / or organic solvents other than the various polymers in the paint, the desired medium of gelled hollow fine particle polymers is directly added with water to the resins. And / or it may be replaced with an organic solvent.

The gelled hollow fine particle polymers thus obtained may be prepared by separating the solid content from the aqueous emulsion or suspension as described above, if necessary, or by using another resin or organic solvent. And / or the presence of particles having a particle size of 30 μm (micron) or more in a medium such as water is 1% by weight or less,
Moreover, the weight average particle diameter is 20 μm or less, and preferably,
It is extremely easy to grind so that the particle size is within the range of 10 μm or less.

The particle distribution of the gelled hollow fine particle polymers has an abundance ratio of particles having a particle diameter of more than 30 μm of 1
When the content is more than or equal to wt% or the weight average particle size exceeds 20 μm, it becomes difficult to prepare a coating composition that gives a smooth coating surface.

The amount of the fine particle polymers (C) described above is 1 of the film-forming component (A).
A suitable proportion is 0.1 to 100 parts by weight with respect to 00 parts by weight.

Next, the solvent (D) may be any solvent as long as it can dissolve or stably disperse the mixture of the film-forming component (A) and the pigment (B). For example, solvents such as those used in preparing the film-forming component (A) can be applied, but these solvents may be used alone or in combination of two or more kinds,
Of course.

The amount of the solvent (D) used or the mixture composition ratio as a mixed solvent is determined according to the coating means, the temperature of the coating material during spraying, and further according to the baking conditions such as the baking temperature or time. , Should be decided as appropriate.

A colored coating material or a top coating material can be prepared by mixing the components described above by a conventional method. In addition to the essential components, curing catalysts, various resins, flow regulators, color separation inhibitors, antioxidants, ultraviolet absorbers and / or silane coupling agents, etc. Known and conventional additives used for paints can be added in conventional amounts.

Of these, only typical ones of the above-mentioned various resins are exemplified, and various fiber-based resins such as nitrocellulose and cellulose acetate butyrate, petroleum resins or ketone resins. And so on

As the above-mentioned silane coupling agents, only typical ones will be exemplified. Γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane. Or γ-mercaptopropyltrimethoxysilane or the like,

As only the representative curing catalysts, for example, "Beckamine P-19" is given.
8 "[Product of Dainippon Ink and Chemicals, Inc.] or" Nature 155, 2500X, X49-110, 352 "
5 or 5225 ”(a product of King, USA).

The amounts of these various additive components to be used should be appropriately determined depending on the baking temperature and the baking time when the colored coating material is used.

Thus, each of the above-mentioned essential components and the various additive components as described above, which are optionally added, are mixed by a conventional method, and the solvent (D) is adjusted. By adjusting the coating viscosity to a desired value, the intended colored paint can be obtained.

Next, the colored coating material is applied onto the base material, and if necessary, a setting time of about several minutes is provided, and then the top coating material is applied.

After that, if necessary, further setting may be carried out for several minutes to several tens of minutes to bake and cure. As the baking conditions of this time,
A suitable range is 60 to 180 ° C. for 10 to 40 minutes, and thus a two-coat colored coating film is obtained.

The thickness of the colored coating film at this time may be the minimum thickness necessary for completely hiding the substrate, and usually 15 to 20 μm or less is appropriate. The film thickness of the paint is usually 30 μm or more, preferably 40 to 40, as the final cured coating film thickness.
About 60 μm is suitable.

The coating composition of the present invention thus obtained is applied to various coatings typified by the coating of automobiles. Therefore, as the substrates to be coated, general metals and Such as plastics,
It can be applied to a wide range of materials and processed products.

[0087]

EXAMPLES Next, the present invention will be described more specifically with reference to Reference Examples, Examples and Comparative Examples. In the following, all parts and% are based on weight unless otherwise specified. .

Reference Example 1 (Preparation Example of Hydroxyl Group-Containing Polymers) A reaction vessel equipped with a stirrer, a thermometer, a nitrogen introducing tube and a reflux condenser was charged with 160 parts of xylene and 160 parts of n-butanol. In a nitrogen atmosphere, the temperature was raised to 125 ° C., where 120 parts of styrene, 180 parts of n-butyl acrylate, 120 parts of n-butyl methacrylate were used.
Part, 108 parts of β-hydroxypropyl acrylate,
66 parts of β-hydroxypropyl methacrylate and 6 parts of acrylic acid, 80 parts of n-butanol, ter
48 parts of t-butyl peroxyoctate, di-ter
A mixture of 3 parts of t-butyl peroxide and 12 parts of azobisisobutyronitrile was added dropwise over 8 hours.

After the dropping was completed, when the temperature was kept at the same temperature for 15 hours to continue the reaction, the nonvolatile content (NV) was 6%.
0%, Gardner color (G.C.) is 1 or less, 2
The Gardner viscosity (G.Vis.) At 5 ° C. is E,
And, the number average molecular weight (Mn) is 3,000, and
A solution of the target polymer having a hydroxyl value (OHV) per solid content of 109 was obtained. Hereinafter, the polymer (a-
It is abbreviated as the solution of 1).

Reference Example 2 (Same as above) The composition of the monomers was 120 parts of styrene, 90 parts of methyl methacrylate and 120 parts of n-butyl methacrylate.
Parts, 114 parts of n-butyl acrylate, 90 parts of β-hydroxypropyl acrylate, 60 parts of β-hydroxypropyl methacrylate and 6 parts of acrylic acid. A polymer solution was obtained. The NV of this is 60%,
G. C. Is 1 or less, and G. Vis. Is H and Mn
Was 3,000. Further, the OHV per solid content of this product was 94. Hereinafter, the polymer (a-
2) is abbreviated.

Reference Example 3 (same as above) In a reaction vessel equipped with a stirrer, a thermometer, a nitrogen introducing tube and a reaction product water distilling tube, 215 parts of adipic acid and 63.8 mol% of all polybasic acid components were added. Equivalent to 400 parts of hexahydrophthalic anhydride and 4 parts of trimethylolpropane
4.6 parts and 390.2 parts of ethylene glycol were charged, the temperature was gradually raised to 230 ° C. over 5 hours in a nitrogen stream, and the same value was kept until the acid value became 10. , OHV was 111 and Mn was 1,010 to obtain an oil-free alkyd resin.

Then, the resin thus obtained is treated at 100 ° C.
Cool to below and add 250 parts xylene to bring the NV to 8
A 0% oil-free alkyd resin solution was obtained. Hereinafter, for convenience, this is abbreviated as polymers (a-3).

Reference Example 4 (Same as above) A polyester reactor similar to that of Reference Example 3 was charged with 157.4 parts of adipic acid and 300 parts of hexahydrophthalic anhydride corresponding to 64.4 mol% of all polybasic acid components. , 203.8 parts of trimethylolpropane and 2 mol of neopentyl glycol, which corresponds to 59 mol% of all alcohol components.
30 parts were charged, the temperature was gradually raised to 230 ° C. over 5 hours in a nitrogen atmosphere, and the temperature was kept at the same value until the acid value became 10, to obtain an alkyd resin.

Then, the resin thus obtained is treated at 100 ° C.
Cool to below and add 250 parts xylene to bring the NV to 8
It was a 0% alkyd resin solution. OHV per solid content of this product was 125, and Mn was 1,140. Hereinafter, for convenience, this is abbreviated as polymers (a-4).

Reference Example 5 (Preparation Example of Polymers Containing Carboxyl Group) A reaction vessel similar to that of Reference Example 1 was charged with 500 parts of xylene and 300 parts of isobutanol and heated to 110 ° C. under a nitrogen atmosphere. 100 parts of styrene, 500 parts of n-butyl methacrylate, 247 parts of n-butyl acrylate, 153 parts of methacrylic acid, 20 parts of tert-butyl peroxyoctate, 5 parts of tert-butyl peroxybenzoate and A mixture of 200 parts of xylene was added dropwise over 4 hours.

After that, keeping at the same temperature for 15 hours, NV is 51.3%, VIS is XY,
At the same time, a polymer solution having Mn of 7,800 was obtained. Hereinafter, this is abbreviated as polymers (a-5).

Reference Example 6 (Preparation Example of Epoxy Group-Containing Polymers) In a reaction vessel similar to that of Reference Example 1, 1,400 parts of xylene was charged and heated to 125 ° C. in a nitrogen atmosphere to give styrene. 100 parts of n-butyl methacrylate 210
Parts, 184 parts of n-butyl acrylate, 506 parts of glycidyl methacrylate, 60 parts of tert-butyl peroxyoctate, 10 parts of di-tert-butyl peroxide and 100 parts of xylene over 6 hours. Was dropped.

After that, when kept at the same temperature for 15 hours, NV was 41.7% and VIS. Is A4-
A solution of the target polymer having A5 and Mn of 2,930 was obtained. Hereinafter, this is abbreviated as polymers (a-6).

Reference Example 7 [Preparation Example of Film Forming Component (A)] Solutions of the respective polymers obtained in Reference Examples 1, 2, 3 and 4 and "Super Beckamine L-117-6" were prepared.
0 ”[butyl etherified melamine resin manufactured by Dainippon Ink and Chemicals, Inc .; NV = 60%] was blended so as to have a solid content weight ratio of 70/30 to obtain a mixed solution. Hereinafter, these are sequentially (A-
1), (A-2), (A-3) and (A-4) are abbreviated.

Reference Example 8 (same as above) Solution of carboxyl group-containing polymers (a-5) obtained in Reference Example 5 and solution of epoxy group-containing polymers obtained in Reference Example 6 (a-6) ) And were mixed so that the functional group equivalent ratio was 1: 1 to obtain a mixed solution.

Reference Example 9 (Preparation Example of Seed Particles) Pure water was charged into a reaction vessel under a nitrogen atmosphere and the temperature was raised to 80 ° C. Then, according to the raw material composition as shown in Table 1, 1/10 of the mixture (a) and 1/5 of the mixture (c) were added, and 30 minutes after that, 9 of the mixture (a) was added. / 10 and 3/5 of the mixture (b) were added dropwise over 3 hours.

After completion of the dropping, 1/5 of the mixture (b) was added, and the mixture was kept at 80 ° C. for 1 hour with stirring to terminate the reaction, whereby a seed emulsion having an NV of 45% was obtained.

[0103]

[Table 1]

<< Footnotes in Table 1 >>"HitenolN-08" ... Daiichi Kogyo Seiyaku Co., Ltd.
Polyethylene dodecyl phenyl ether sulfate ammonium salt

Reference Example 10 [Preparation Example of Gelled Hollow Particle Polymers (C)] The mixture (C) was stirred in a reaction vessel according to the raw material charging composition shown in Table 2 and the temperature was raised to 80 ° C. Warm, pH
To 3-4.

Then, 1/20 of the mixture (d) and 1/5 of the mixture (e) were added, and further 30 minutes later,
19/20 of the mixture (d) and 3/5 of the mixture (e) were added dropwise over 3 hours.

After completion of the dropping, 1/5 of the mixture (e) was added, and the mixture was kept at 80 ° C. for 1 hour with stirring, and then the reaction was terminated. After that, the emulsion thus obtained is cooled to 30 ° C. and added with a 25% aqueous ammonia solution to p.
Adjust H to 8.5-9, stir for an additional 30 minutes, then NV
Of 45% and a particle size of 0.23 μm was obtained. The emulsion was filtered through a 200-mesh filter cloth and spray-dried.

The emulsion particles obtained here were confirmed to be hollow particles by a scanning electron microscope (SEM). Hereinafter, this is referred to as fine particle polymers (C-1)
Is abbreviated.

[0109]

[Table 2]

<< Footnotes in Table 1 >>"Lebenol Lu WZ" ... Sodium polyoxyethylene dodecyl phenyl ether sulfate ester manufactured by Kao Corporation

Examples 1-10 and Comparative Examples 1-1
0 Polymers (a-1) to (a-obtained in Reference Examples 1 to 4)
4) and "Super Beckamine L-117-60" as aminoplast, or the carboxyl group-containing polymers (a-5) obtained in Reference Example 5 and Reference Example 6
While using the epoxy group-containing polymers (a-6) obtained in (1) and the curing catalyst in the form of a mixture as a film-forming component,

The fine particle polymers (C-
1) and, if necessary, the pigments (B) as well, and each of these components is made into a coating material at the compounding ratios shown in Tables 3 and 4, respectively. Colored stock solutions and topcoat stock solutions were obtained. However, in the case of the comparative example, the use of fine particle polymers was completely omitted.

Then, the solvents (D-1) and (D-
2) as toluene / xylene / ethyl acetate / cellosolve acetate = 40/20/20/20, respectively
(Weight ratio) mixed solvent and "Solvesso 100"
(Aromatic hydrocarbon mixture manufactured by Exxon Corporation, USA) The spray viscosity was adjusted with a thinner diluted with both solvents to obtain a dual-purpose paint.

After that, one of the colored paints is spray-coated so that the dry film thickness is about 10 μm, set for 5 minutes, and the other top-coating clear paint is spray-coated so that the dry film thickness is about 55 μm. And then 20
After setting for 1 minute, baking is performed at 140 ° C for 25 minutes, so-called 2 coat 1
The bake method was adopted.

The coated plates used in this case were electrodeposited coated plates such as "Beckolite CF-542" (hydroxyl group-containing polyester resin manufactured by Dainippon Ink and Chemicals, Inc.) and "Super Beckamine L-117-60". It is prepared by applying a so-called intermediate coating composition consisting of the above-mentioned "and carbon black" and baking it.

With respect to each of the thus obtained cured coating films, the finish state of the coating film surface was evaluated and judged, and the results are shown together in the same table.

[0117]

[Table 3]

<< Footnote in Table 3 >> (a-1) to (a in the table
-6) is an abbreviation for "polymers (a-1)" to "polymers (a-6)", and "component A", "component B" and C are respectively "film". Forming component (A) ",
"Pigments (B)" and "particulate polymers (C)" are abbreviations, and "Super Beckamine" is an abbreviation for "Super Beckamine L-117-60". The numbers mean "parts."

As the "pigment (1)", "Alpaste 7160N" (aluminum paste manufactured by Toyo Aluminum Co., Ltd .; NV = 65%) was used, and the pigment weight concentration (PWC) was 14%. As the "pigment (2)", "Fastogen Blue NK" [Cyanine Blue manufactured by Dainippon Ink and Chemicals, Inc .; NV = 100%] was used as the "Pigment (2)". The mixture was used so as to be 15%.

As the "curing catalyst", "Nakeure 5225" (active ingredient = 25%) was used and added at a ratio of 0.5% based on the resin solid content.

[0121]

[Table 4]

[0122]

[Table 5]

<< Footnote in Table 4 >> (a-1) to (a in the table
-6) is an abbreviation for "polymers (a-1)" to "polymers (a-6)", and "component A" is an abbreviation for "film forming component (A)". Yes, and "Super Beckamine" is "Super Beckamine L-117-6.
It is an abbreviation for "0", and each number in the table means "part".

As the "curing catalyst", "Nature 5225" (active ingredient = 25%) was used and added at a ratio of 0.5% based on the resin solid content.

[0125]

[Table 6]

<< Footnote in Table 5 >>"Pigmentarrangement" was visually determined. Judgment standard: ○ ……… Good △ △ …… Slightly bad × ……… Extremely bad

The "gloss" was visually determined. Judgment standard: ○ ……… Good △ △ …… Slightly bad × ……… Extremely bad

"GM-26D" [MURAKAMI C
Gloss measuring instrument made by OLOR REAARCHLABORATORY], a so-called Murakami glossiness tester, and the data that the reflection angle is 20 degrees (that is, 20 ° Gl
oss).

The "coating state" is "good"("○") when neither "repelling" nor "pinhole" is found in the cured coating film, and "repelling" or "pinhole" is recognized. Those that were evaluated as extremely poor (“x”).

[0130]

[Table 7]

[0131]

[Table 8]

[0132]

[Table 9]

[0133]

The coating composition of the present invention obtained as described above is particularly excellent in curability, and in addition,
A highly practical cured coating that maintains high appearance and is excellent in weather resistance without causing various coating defects such as "sag", "repellency" and "pinhole". To give.

Claims (7)

[Claims] 1. A film-forming component (A) and a pigment (B)
And a film-forming component (A), the above-mentioned pigments (B) and the following solvents (D) are immiscible with each other and can be stably dispersed. A fine particle polymer (C) having: and a solvent (D) as essential components, a coating composition. 2. The film-forming component (A) contains an acrylic copolymer having a hydroxyl group or a carboxyl group as an essential component.
The coating composition according to. 3. The coating composition according to claim 1, wherein the film-forming component (A) contains an acrylic copolymer having both a hydroxyl group and a carboxyl group as an essential component. 4. The film-forming component (A) comprises at least one hydroxyl group-containing resin selected from the group consisting of alkyd resins, oil-free alkyd resins and urethane resins, and aminoblast. The coating composition according to claim 1, which is a product. 5. The paint according to claim 1, wherein the pigment (B) is at least one selected from the group consisting of aluminum powder, copper powder, zinc powder, inorganic powder and organic powder. Composition. 6. The coating composition according to claim 1, wherein the fine particle polymer (C) is a polymer prepared by an emulsion polymerization method and is substantially insoluble in the solvent (D). Stuff. 7. The coating composition according to claim 1, wherein the fine particle polymer (C) has an intramolecular crosslinked structure.