JPH023829B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a coating composition, and more particularly to a coating composition containing novel copolymer fine particles useful as an automotive or other decorative coating. In recent years, so-called high-solids coating compositions, in which cross-linked polymer fine particles called microgels are dispersed in a coating composition containing a resin vehicle, have been attracting attention in automobile painting and other fields due to their workability and coating performance. There is. The microgel particles are made of a polymer that is insoluble in the organic solvent for the coating material in which they are to be dispersed and are crosslinked to some extent, have a microscopic particle size, and must be stably dispersed in the composition. Various methods have been proposed to produce microgels, one of which is to emulsion polymerize an ethylenically unsaturated monomer with a crosslinkable copolymerizable monomer in an aqueous medium to form a fine particle copolymer. The other method is to obtain microgel particles by removing water by manufacturing, solvent replacement, azeotropy, centrifugation, filtration, drying, etc., and the other method is to obtain microgel particles by dissolving monomers such as aliphatic hydrocarbons but not dissolving polymers. This method was called the NAD method, in which an ethylenically unsaturated monomer and a crosslinkable copolymerizable monomer are reacted in an aqueous organic solvent, and the resulting fine particle copolymer is fractionated. In this internal emulsion polymerization method, relatively fine particles can be easily obtained, and the heat of reaction can be easily removed, making it suitable for industrial use. However, it only requires an operation to remove water from the emulsion product. In order to disperse the monomers to be copolymerized in an aqueous medium, a comparatively low molecular weight compound consisting mainly of anionic or cationic surfactants is required as an emulsifier, and this surfactant increases the weight of the fine particles produced. Since it is attached to the coalescence, when a coating film is formed, it is mixed into the coating film, and it is unavoidable that it will adversely affect the coating performance. In addition, an aqueous medium is used in emulsion polymerization, and volatile organic solvents such as aromatic solvents are used in coatings.However, during emulsion polymerization, an emulsifying dispersant that helps in particle dispersion is used as it is for microgel particles in the coating composition. It is difficult to use it for dispersion, and some kind of ingenuity is required for stable dispersion of microgels in paint compositions. On the other hand, in the NAD method, a non-aqueous solvent that does not dissolve the polymer is used as the reaction medium, so it can be added to the coating composition as it is without separating the microgel, and it also has the advantage of being easy to separate. However, this method also has many problems different from those of emulsion polymerization. First, when an ethylenically unsaturated monomer and a crosslinkable comonomer are copolymerized in a nonaqueous organic liquid, a special dispersion stabilizer is required to form a microgel. Usually, this dispersion stabilizer is a graft copolymer consisting of a polymer main chain that is not solvated by the organic liquid of the reaction medium and a polymer chain that is bonded to the main chain as a side chain and is solvated by the organic liquid. However, it is necessary to carefully select the graft copolymer, taking into account its affinity for polymer particles and affinity for solvents, depending on the type of monomer to be microgelled, the type of non-aqueous organic liquid to be used, etc. It is. In addition, when preparing microgels, a low polarity solvent mainly composed of aliphatic hydrocarbons is usually used as the organic liquid, and relatively highly polar organic solvents are used for making paints. Dispersion stabilizers have a problem in that they are almost ineffective in stabilizing the dispersion of microgels in coating compositions. As one of the solutions, for example,
53-133234; 53-133235; 53-133236; 54-
In No. 150439, etc., the microgel is modified by polymerizing the monomer on the microgel particles to form a polymer having the same composition as the film-forming polymer used to make the paint. There is.
As described above, there are various problems in the conventional production of microgels and in the preparation of high-solids coating compositions using microgels, and methods for producing microgels include emulsion polymerization, NAD method, and condensation polymerization of polyester, etc. Each of these methods has advantages and disadvantages, and at present no microgels or high solids coating compositions have been produced that are industrially fully satisfactory. The present inventors previously found that the formula

[Formula] (In the formula, R is a C ₁ to C ₆ alkylene group or phenylene group that may have a substituent, and Y is -
Alkyd resins, polyester resins, acrylic resins, melamine resins, polyether resins, etc. that have groups represented by COOH or -SO ₃ H groups have amphoteric groups in their molecules, so they have unique reactivity, surface activity, and electrical properties. He applied for a patent after discovering that it has chemical properties and is extremely useful as an emulsifier or dispersant when carrying out emulsion polymerization of ethylenically unsaturated monomers in an aqueous medium in the presence of a polymerization initiator. (Special Application No. 56-71864). The above invention uses a monomer having two or more radically polymerizable ethylenically unsaturated groups in the molecule as one type of ethylenically unsaturated monomer, and also contains the amphoteric group in the molecule. An emulsion resin is obtained by copolymerizing polymerizable monomers in an aqueous medium using a water-soluble resin as an emulsifier. does not contain a protective colloid and is copolymerized with a monomer having two or more radically polymerizable ethylenically unsaturated groups in the molecule, improving the water resistance, solvent resistance, and gloss of the coating film. It focused on the following points. The present inventors further discovered that the particle size of the emulsion resin is extremely fine, about 0.02 to 0.5μ;
When the water is removed and the resin is isolated, some agglomeration is observed, but the particle size is about 40μ, which is a size that does not interfere with coating film formation, and if desired, it can be easily made fine by mechanical means. What can be done is that the resin is cross-linked and insoluble in ordinary paint-forming solvents, and that a zwitterionic group-containing resin with specific surface activity and electrochemical properties is attached to the cross-linked polymer fine particles. As a result, the polymer particles obtained by removing water from the above emulsion resin were used as film-forming polymers and volatile organic liquids. A separate patent application was filed on the same date as the present application for a so-called high solids type coating composition in which a system consisting of a diluent and a crosslinking agent is dispersed. (Patent Application No. 13053 (1982)
(No. 129066)) However, the fine particle polymer shown in the same patent application has a formula in the molecule. (In the formula, R is a C ₁ to C ₆ alkylene group or phenylene group that may have a substituent, and Y is -
Copolymerization of two or more monomers having α,β-ethylenically unsaturated groups in an aqueous or organic medium using a resin having a group represented by COOH or -SO ₃ H group) as a dispersion stabilizer. Since these are crosslinked polymer fine particles obtained by
On the surface of the microparticles of the crosslinked copolymer, within the molecules mentioned above,

[Formula] When a resin having a group is attached in some way and is used as a coating composition, the parent solvent portion of the dispersion stabilizer spreads into the solvent and the resin is engaged with the fine particles. As long as the particulate polymer is present, a stable dispersion of the particulate polymer can be obtained, but if for some reason it separates from the particulate polymer and flows out, the stability of the particulate polymer decreases, and the viscosity of the entire system increases, causing the original high solids coating composition to deteriorate. There is a risk that the advantages of Therefore, the present inventors expect the above-mentioned amphoteric group-containing resin to play a role as a dispersion stabilizer, and
We continued our research with the intention of ensuring stable dispersibility of the fine particle polymer by covalently integrating the resin into the crosslinked copolymer fine particles and preventing the flow of the dispersion-stable resin from the fine particle body, and developed the present invention. I was able to complete it. That is, according to the present invention, a film-forming polymer (A) having a functional group capable of reacting with a crosslinking agent, and a volatile organic liquid diluent that supports the polymer.
(B), polymer fine particles (C) that are insoluble and stably dispersed in the combination of the polymer and diluent, and a crosslinking agent (D) that is dissolved in the diluent; Polymer fine particles (C) have a formula in the molecule (In the formula, R is a C ₁ to C ₆ alkylene group or phenylene group that may have a substituent, and Y is -
In an aqueous or _organic medium, two or more types of α,β-ethylenically unsaturated A coating composition is provided which is a crosslinked polymer fine particle obtained by copolymerizing a monomer having a group. In a preferred embodiment, the coating composition of the present invention uses the film-forming polymer (A) and the crosslinked polymer fine particles (C) in a weight ratio of 50 to 99.5 parts and 50 to 0.5 parts,
In addition, the crosslinking agent (D) is 5 to 5 parts per 100 parts of polymer components (A) + (C).
100 parts, and the organic diluent (B) is 10 to 2000 parts per 100 parts of the total amount of polymer components and crosslinking agent (A) + (C) + (D).
Used in parts by weight. Film-forming polymer having a functional group capable of reacting with a crosslinking agent in the above-mentioned coating composition according to the present invention
(A) is a known film-forming polymer such as acrylic resin, alkyd resin, polyester resin, epoxy resin, silicone resin, or urethane resin, which has a functional group such as a hydroxyl group or a carboxyl group. Value 0.5~60, Hydroxyl value 20~200, Number average molecular weight 500~10000
It is of a certain degree. These polymers are usually mixed with a crosslinking agent (D) to achieve or promote curing. Suitable crosslinking agents include diisocyanates, diepoxides, aminoplast resins, etc., which are usually dissolved in the polymer diluent and react with the functional groups of the film-forming polymer during or after coating to create a three-dimensional cure. Forms a coating film. Particularly preferred crosslinking agents are melamine formaldehyde condensates in which a substantial proportion of the methylol groups have been etherified by reaction with butanol or methanol. The above-mentioned film-forming polymer can be present in the diluent (B) in a dissolved or dispersed state, or can be present in a partially dissolved or partially dispersed state.
In this case, volatile organic liquids are used, typically aromatic hydrocarbons such as toluene, xylene, various petroleum fractions containing aromatics; esters such as butyl acetate, ethylene glycol diacetate, 2-ethoxyethyl Examples include acetate and the like; ketones such as acetone and methyl isobutyl ketone; alcohols such as butyl alcohol; and aliphatic hydrocarbons or mixtures thereof. The coating composition of the present invention further contains, as the most characteristic part, special new polymer fine particles stably dispersed in the above-mentioned system of film-forming polymer, volatile organic liquid diluent, and crosslinking agent. Since the polymer particles are composed of a crosslinked copolymer, they are insoluble in the combination of film-forming polymer and diluent. Moreover, it exhibits various interfacial properties within the molecule depending on various environments.

[Formula] Because a resin containing a polymerizable unsaturated bond (referred to as an oligosoap) is used as a dispersion stabilizer, the reaction medium used to produce the fine particle polymer can be either aqueous or non-aqueous. It also exhibits affinity for media, and can be expected to have a stabilizing effect on the dispersion of fine particle polymers. Furthermore, the above-mentioned dispersion stabilizer is integrally incorporated into the fine particles as a component of the crosslinked copolymer through polymerizable unsaturated bonds, and the dispersion stabilizer portion does not flow out from the fine particle polymer. Moreover, the crosslinked copolymer oligosoap prepared in this manner exhibits good affinity for relatively polar volatile organic diluents in coating compositions, and therefore, it is possible to easily transfer fine particle polymers into the system. It also helps to stabilize the dispersion. As already mentioned, insolubility of the polymer fine particles in the combination of the film-forming polymer and the diluent is achieved in the present invention by making the polymer fine particles a crosslinked copolymer. In two or more α,β-unsaturated monomers to be polymerized,
At least one type of monomer having two or more radically polymerizable ethylenically unsaturated groups in the molecule,
Alternatively, it contains a monomer having two types of ethylenically unsaturated groups each carrying a group that can react with each other,
They are further copolymerized with one or more other copolymerizable monomers. Therefore, in the present invention, the term "monomer having two or more types of α,β-ethylenically unsaturated groups" refers to a combination of a crosslinking monomer and a non-crosslinking monomer as described above. It should be understood what is intended. In addition, two or more polyfunctional monomers for crosslinking or groups capable of reacting with each other are present in the monomers having two or more α,β-ethylenically unsaturated groups to be copolymerized. Regarding the proportion of unsaturated monomers of the species, they should be present in an amount of 0.01 to 20% by weight of the total monomers, preferably 0.1 to 20% by weight of the total monomers.
The amount is selected to be within the range of 10% by weight, but these are not critical and the point is that the resulting fine particle copolymer does not dissolve in the combination of film-forming polymer and organic diluent. It should be selected to provide sufficient crosslinking. Usually, the insolubility of this fine particle polymer is determined by adding 1% by weight of the fine particles to an organic diluent such as tetrahydrofuran, shaking for 30 minutes, and centrifuging at 17000 rpm for 30 minutes.
Remove the supernatant liquid, separate and dry the residue, weigh it,
Comparing the results with the initial weight, if the microparticles are acceptably insoluble in the diluent alone;
It is also determined to be insoluble in the film-forming polymer and diluent combination. Monomers having two or more radically polymerizable ethylenically unsaturated groups in the molecule (polyfunctional monomers) used in the present invention include polymerizable unsaturated monocarboxylic acid esters of polyhydric alcohols, Examples include polymerizable unsaturated alcohol esters of polybasic acids and aromatic compounds substituted with two or more vinyl groups, examples of which include the following compounds. Ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol dimethacrylate acrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate,
Pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerol dimethacrylate,
Glycerol diacrylate, glycerol acroxy dimethacrylate, 1,1,1-trishydroxymethylethane diacrylate, 1,1,
1-trishydroxymethylethane triacrylate, 1,1,1-trishydroxymethylethane dimethacrylate, 1,1,1-trishydroxymethylethane trimethacrylate, 1,1,
1-trishydroxymethylpropane diacrylate, 1,1,1-trishydroxymethylpropane triacrylate, 1,1,1-trishydroxymethylpropane dimethacrylate, 1,
1,1-trishydroxymethylpropane trimethacrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, diallyl phthalate and divinylbenzene. In addition, two groups each carrying a group that can react with each other
Examples of monomers having ethylenically unsaturated groups include epoxy group-containing ethylenically unsaturated monomers such as glycidyl acrylate and glycidyl methacrylate, and carboxyl group-containing ethylenically unsaturated monomers such as acrylic acid, methacrylic acid, and crotonic acid. Monomers are the most representative. However, mutually reactive groups are not limited to these, and include, for example, amine and carbonyl; epoxide and carboxylic acid anhydride; amine and carboxylic acid chloride; alkyleneimine and carbonyl; organoalkoxysilane and carboxyl; hydroxyl and Various isocyanates and the like have been proposed, and the present invention includes all of these. In the present invention, in addition to these crosslinking monomers, any monomer having an α,β-ethylenically unsaturated group is used as a copolymerization component, and one polymerizable group is contained in these molecules. The monofunctional monomers can be roughly classified into the following groups. ) Carboxyl group-containing monomers, such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, etc. ) Hydroxyl group-containing monomers, such as 2-hydroxyethyl acrylate, hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, allyl alcohol,
Metaallyl alcohol etc. ) Nitrogen-containing alkyl acrylates or methacrylates, such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, etc. ) Polymerizable amides, such as acrylamide,
methacrylic acid amide etc. ) Polymerizable nitriles, such as acrylonitrile, methacrylonitrile, etc. ) Alkyl acrylates or methacrylates, such as methyl acrylate, methyl methacrylate, ethyl acrylate, n-butyl acrylate, n-butyl methacrylate, 2
- Ethylhexyl acrylate, etc. ) Polymerizable aromatic compounds, such as styrene, α
-Methylstyrene, vinyltoluene, t-butylstyrene, etc. ) α-olefins, such as ethylene, propylene, etc. ) Vinyl compounds, such as vinyl acetate, vinyl propionate, etc. ) Diene compounds, such as butadiene, isoprene, etc. These monomers may be used alone or in combination. In the present invention, as described above, "two or more types of α, β
- a monomer having an ethylenically unsaturated group" in an aqueous or organic medium, (In the formula, R is a C ₁ to C ₆ alkylene group or phenylene group that may have a substituent, and Y is -
It is copolymerized in the presence of a resin having a group represented by COOH (COOH or -SO ₃ H group) and a polymerizable α,β-unsaturated bond. in the molecule

[Formula] The resin having a polymerization-reactive α,β-unsaturated bond includes various resins having these groups and bonds, such as alkyd resins, polyester resins, modified epoxy resins, acrylic resins, and polyether resins. Among these, alkyd, polyester, and acrylic resins are preferred. These resins may be used during or after their manufacture.

[Formula] groups can be incorporated. Also, since it is easy to support -COOH or epoxy groups in the resin, epoxy-containing unsaturated compounds such as glycidyl acrylate and glycidyl methacrylate are used for resins having carboxyl groups, and for resins having epoxy groups, By reacting α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid,

[Formula] A resin having both a group and a polymerizable α,β-unsaturated bond can be easily obtained. A more specific explanation of these resins is as follows. Alkyd resins and oil-free polyester resins having amphoteric groups were developed in a patent application filed by the present inventors.
It is described in No. 54-110865 and No. 55-56048. Alkyd resins and polyester resins are characterized by using polybasic acids and polyhydric alcohols as essential components to generate continuous ester chains. (In the formula, R ₁ is an alkyl group having at least one hydroxyl group, R ₂ and R ₃ are the same or different and are hydrogen or an alkyl group that may have a substituent, and A may have a substituent. C ₁
~ C ₆ alkylene group or phenylene group) can be used to produce an alkyd resin or polyester resin having the above-mentioned amphoteric group (for details, refer to the above-mentioned Japanese Patent Application No. 110865/1986). , see No. 55-56048). In the present invention, alkyd or polyester resins having these amphoteric groups (preferably number average molecular weight
500-5000) plus glycidyl acrylate,
By reacting glycidyl methacrylate, etc., the residual carboxyl group and glycidyl group form α, β
-Incorporating unsaturated bonds into the resin makes it polymerizable. formula

A modified epoxy resin having the group [Formula] in its molecule is described in Japanese Patent Application No. 116293/1983 by the present inventors. Generally, epoxy resin has a formula at the end. (In the formula, R ₄ and R ₅ are hydrogen or methyl groups.) It is characterized by having a group represented by the formula R ₆ -NH-A-SO ₃ M () (in the formula, R ₆ is The oxirane ring is cleaved by reacting an alkyl group that may have a substituent that does not react with the epoxy group, M is an alkali metal or ammonium group, and A is the same as above. part is expression A modified epoxy resin is obtained. The hydrophilicity of the modified epoxy resin increases in proportion to the degree of substitution of the amphoteric group of the formula () (for details, see Japanese Patent Application No. 116293/1983). In the present invention, a portion of the terminal group of the epoxy resin is further reacted with an α,β-unsaturated carboxylic acid such as acrylic acid or methacrylic acid to form an α,β-unsaturated carboxylic acid that is polymerizable with the amphoteric group. A resin is created that incorporates both sides of the bond. formula

[Formula] Regarding the acrylic resin having a group in the molecule, patent application No. 123899 of the present inventors
The formula described in No. 53-125996, No. 47651-47651 and No. 47652-1983 (In the formula, R ₇ , R ₈ , R ₉ , R ₁₀ are H, CH ₃ ,
is any of C ₂ H ₅ , and R ₁₁ is H or a C ₁ to C ₂₀ alkyl group that may contain a -SO- group, -COO, or -O- group in the chain; ,
R ₁₂ is -OH group, -SH group, -SR ₁₃ group (R ₁₃ is C ₁ - _{C 4}
a C 1 -C 12 alkylene group, which may be substituted with any one of the following alkyl groups), and which may be substituted with one or _more C _{1 -C 4} alkyl groups, and A is COOHH group or SO ₃ H
group) or formula (In the formula, R ₁₄ , R ₁₅ , R ₁₆ are each H or C ₁ to _{C 6}
is an alkyl group, and R ₁₇ is H or -SO- in the chain.
a _C1 to _C20 alkyl group which may contain either a group, -COO-, or -O-, or

[Formula] group, and R ₁₈ is a C ₂ -C ₁₂ alkylene group which may be substituted with one or more C ₁ -C ₆ alkyl groups) or the formula (In the formula, R ₁₉ , R ₂₀ , and R ₂₁ are each the same or different and are H or CH ₃ , and R ₂₂ has at least one hydroxyl group and may contain -O- or -COO- in the alkyl skeleton. C ₁ to C ₂₀ alkyl group, R ₂₃ has at least one hydroxyl group and -O- or -COO- in the alkyl skeleton
C ₁ -C ₂₀ alkyl group which may contain or H
or a _C1 to _C20 alkyl group, _R24 is basically an alkylene group represented by ( _CH2 )n (n is 1 to 6) and may be substituted, and A is _CO2
or SO ₃ ) or the formula (In the formula, R ₂₅ , R ₂₆ , and R ₂₇ are each the same or different and are H, or CH ₃ , R ₂₈ , and R ₂₉ are each the same or different and are C ₁ to C ₂₀ -O- or -COO
An alkyl group or a cycloalkyl group that may contain - or R ₂₈ and R ₂₉ combine to form a heterocycle containing an N atom, and R ₃₀ is basically (CH ₂ )
an optionally substituted alkylene group represented by n (n is 1 to 6), and A is CO ₂ or SO ₃
); and a hydroxyl group-containing monomer, a carboxyl group-containing monomer, a glycidyl group-containing monomer, an alkyl acrylate or methacrylate, a nitrogen-containing alkyl acrylate or methacrylate. , a polymerizable amide, a polymerizable nitrile, a polymerizable aromatic compound, an α-olefin compound, a vinyl compound and a diene compound. Therefore, it is produced by solution polymerization in an organic solvent. For details of the above-mentioned polymerizable amino acid compounds, please refer to the above-mentioned patent application No. 53-123899;
No. 125996, No. 125996, No. 47651/1982, No. 47652/1983, and Japanese Patent Application No. 71864/1983 for details of the above-mentioned acrylic resin having a -N--RY group in the molecule. However, in the present invention, it is necessary to further introduce α,β-unsaturated bonds into the resin.
It is necessary to contain a carboxyl group- or glycidyl group-containing monomer in the monomers to be copolymerized. obtained in this way

[Formula] An acrylic copolymer having a group in the molecule is reacted with glycidyl acrylate, glycidyl methacrylate, etc. when there is a carboxyl group, or with acrylic acid, methacrylic acid, etc. when there is a glycidyl group. α,β of
-Introducing unsaturated bonds, number average molecular weight 500 to 10,000
Those of about 100% are preferably used in the present invention. formula

Regarding the polyether resin having a group represented by the formula:
-The formula at the end as described in No. 116293 (In the formula, R ₃₁ and R ₃₂ are hydrogen or methyl groups.)
Reacting a compound of R ₃₃ -NH-A-SO ₃ M (in the formula, R ₃₃ is a substituent that may have a substituent that does not react with an epoxy group, M is an alkali metal or ammonium group, and A is an alkylene group). The oxirane ring is cleaved by A modified polyether type epoxy resin is obtained. Polyether type epoxy resins are well known and various types are commercially available, and they can be obtained by reacting polyhydric phenols or polyhydric alcohols other than bisphenol A with halohydrin. (For details, see the above-mentioned Japanese Patent Application No. 116293/1983).
In the present invention, a polyether type epoxy resin having a polymerizable α,β-unsaturated bond introduced into a portion of the terminal group by reaction with acrylic acid, methacrylic acid, etc. is further used. Each resin mentioned above has a characteristic formula in its molecule. It contains an amphoteric group represented by the formula and exhibits affinity and solubility for both aqueous and non-aqueous solvents. Water solubility can be further ensured by introducing hydrophilic groups into the resin. In addition, since it has α,β-unsaturated bonds along with the above-mentioned amphoteric group, it easily participates in copolymerization reaction by radical polymerization, and is able to form a resin part.

A resin having a structure in which an oligosoap having an amphoteric moiety of the formula is covalently integrated with crosslinked polymer fine particles is produced. Because the oligosoap is integrated into the microparticle polymer, a solvated barrier is formed around the microparticles in both aqueous and non-aqueous solvents, which has the effect of stably dispersing the microparticles in the solvent. can get. Therefore, if the resin of the present invention is used, it is possible to co-contain two or more monomers having ethylenically unsaturated groups, consisting of a crosslinking monomer and a non-crosslinking monomer, in either an aqueous or a non-aqueous reaction medium. By polymerization, crosslinked copolymer fine particles can be produced, and since the oligosoap itself can be covalently integrated with the crosslinked copolymer, fine particles can be obtained without the need for modification of the fine particles. The oligosoap can be dispersed in a relatively polar solvent while remaining insoluble, and since the oligosoap does not flow out from the fine particles, stable dispersion can be ensured. The production of particulate copolymers in an aqueous medium is carried out as follows. Polymerization is preferably carried out by dropping a monomer mixture in a predetermined ratio into an aqueous medium containing the oligosoap in the presence of a polymerization initiator. formula

The resin having the amphoteric group and α,β-unsaturated bond of [Formula] is 0.3 to 8%, more preferably 0.5 to 6%, based on the total weight of the monomer mixture.
It is sufficient to use it. The non-volatile content of the obtained emulsion resin is 2.
It is preferable to use it at a ratio of ~65%, preferably 20~60%, and further to help dissolve the resin (oligosoap) having the above-mentioned amphoteric group and polymerizable α,β-unsaturated group. , preferably contains a base in an amount corresponding to its acid value. Alkali hydroxide, ammonia, and organic amines can be used as the base, but ammonia or organic amines are particularly preferred since they are free from volatilization and leave inorganic ions in the coating film. The aqueous medium may also contain organic solvents that are miscible with water. As the polymerization initiator, ordinary ones can be used, such as organic peroxides such as benzoyl peroxide, t-butyl peroxide, and cumene hydroperoxide, azobiscyanovaleric acid, azobisisobutyronitrile, azobis-(2,4 -dimethyl)
organic azo compounds such as valeronitrile, azobis-(2-amidinopropane) hydrochloride, inorganic water-soluble radical initiators such as potassium persulfate, ammonium persulfate, sodium persulfate, hydrogen peroxide; Examples include redox initiators obtained by combining sodium pyrosulfite, sodium bisulfite, divalent iron ions, etc., and these can be used alone or as a mixture of two or more. Such a polymerization initiator may be added to the reaction medium in advance, or may be added dropwise at the same time as the constituent monomers. The amount of these polymerization initiators used is usually 0.05 to 5%, preferably 0.1 to 3% based on the total monomers.
Selected within a range of %. Further, if necessary, an appropriate amount of a conventional chain transfer agent (for example, mercaptans such as lauryl mercaptan and hexyl mercaptan) may be used in combination. By the above emulsion polymerization method, a milk-like or cream-like emulsion resin that is stably dispersed in water is obtained.
The average particle size of this resin is about 0.02 to 0.5 μm. If water is removed from this emulsion by an appropriate means such as spray drying, solvent substitution, azeotropy, centrifugation, or over-drying, secondary particles of somewhat agglomerated copolymer fine particles up to about 40μ can be obtained. ,
No fusion is observed, and it can be added as it is or after being pulverized if desired, to a high solids coating composition as insoluble polymer fine particles. For drying the emulsion, it is particularly preferable to use spray drying means from the viewpoint of workability and particle size of secondary particles. The above polymer fine particles used in the present invention also contain

It can also be produced by the so-called NAD method in a non-aqueous organic medium using a resin having an amphoteric group of the formula and a polymerizable α,β-unsaturated bond as a dispersion stabilizer. As the non-aqueous organic medium, a low polar organic solvent that dissolves the monomer but does not dissolve the polymer, such as an aliphatic hydrocarbon such as hexane, heptane, or octane, is usually used. within the molecule

By selecting a resin having a [formula] group and a polymerizable α,β-unsaturated bond, the resin is rendered soluble in the reaction medium and its specific surfactant and electrochemical properties make it Acts as an effective dispersion stabilizer within. The initiator, reaction operation, post-treatment, etc. when using the NAD method are well known to those skilled in the art, and the details will be omitted. N.A.D.
Even when using this method, a stabilized copolymer of oligosoap can be obtained as fine particles with an average particle size of about 1 to 40 μm. As described above, the fine particle polymer of the present invention uses a resin having an amphoteric group and a polymerization-reactive α,β-unsaturated bond as an emulsifier or a dispersant, so it can be used in both the emulsion polymerization method and the NAD method. Not only can it be produced by the method, but it also opens the door to the production of crosslinked fine particles by easier-to-operate suspension polymerization or bulk polymerization. Moreover, the fine particles obtained are not contaminated with impurities such as low molecular weight emulsifiers or dispersion stabilizers unlike conventional methods, and have a unique affinity for both aqueous and non-aqueous solvents as well as various solvents of different polarity. Oligosoap exhibiting medium properties is integrated by covalent bonds, and when dispersed in a solvent, this oligosoap flows out from the fine particles and does not interfere with the dispersion stability of the fine particles. Further, it can be dispersed and contained in a high solids coating composition without any modification treatment. The integration of the crosslinked copolymer and oligosoap also prevents the migration of the oligosoap within the coating film, and therefore the three-dimensional coating film has the effect of improving its physical properties. It is. The coating composition of the present invention is particularly useful as a high solids coating composition for automobiles or other decorative applications, and metal or nonmetallic pigments and any other known coating additives may be added thereto. The present invention will be specifically explained below using Reference Examples, Examples, and Comparative Examples. In the example sentence, ``chubu'' and ``%'' indicate parts by weight, and % indicates % by weight. Reference Example 1 Production of polyester resin having amphoteric groups and polymerizable α,β-unsaturated bonds: Bishydroxyethyltaurine was placed in a 2-colben equipped with a stirrer, a nitrogen inlet tube, a temperature control device, a condenser, and a decanter. 213 parts of 1,6-hexanediol, 236 parts of 1,6-hexanediol, 296 parts of phthalic anhydride, 376 parts of azelaic acid, and 44 parts of xylene were charged and the temperature was raised. Water produced by the reaction was removed by azeotroping with xylene. The temperature was raised to 210° C. over about 3 hours from the start of reflux, and the reaction was continued with stirring and dehydration until the acid value equivalent to carboxylic acid reached 125. this
After lowering the temperature to 140°C, while maintaining this temperature, 250 parts of "Cardular E10" (manufactured by Ciel, glycidyl ester of versatate) was added dropwise over 30 minutes, and stirring was continued for 2 hours. This was lowered to 80°C, and 0.05 parts of hydroquinone monomethyl ether, 140 parts of xylene, 170 parts of glycidyl methacrylate,
7.5 parts of triethylamine was added and the reaction was completed at 90°C for 3 hours. This product had an acid value of 53, a hydroxyl value of 73, a number average molecular weight of 1110, and an iodine value of 21.9. Reference Example 2 Production of Polymer Fine Particles 25 parts of the polyester resin obtained in Reference Example 1 was placed in a reaction vessel equipped with a stirrer, a cooling condenser, and a temperature control device.
1.7 parts dimethylethanolamine, 508 parts deionized water
The temperature was brought to 80°C while stirring. After adding 90 parts of the following initiator solution to this, dropwise addition of the following monomer mixture was immediately started. Initiator solution Azobiscyanovaleric acid 10 parts Deionized water 100 parts Dimethylethanolamine 10 parts Monomer mixture Methyl methacrylate 125 parts n-Butyl acrylate 165 parts Styrene 125 parts 2-Hydroxyethyl acrylate 50 parts Ethylene glycol dimethacrylate 10 After finishing the dropping for 60 minutes, remove the remaining initiator solution.
30 parts were added and stirring was continued for 30 minutes to complete the reaction. The particle size of the microgel dispersion in the obtained emulsion (measured using a transmission electron microscope) was 0.083μ. This emulsion was spray-dried to obtain fine polymer particles. Reference Example 3 Production of Polymer Fine Particles In the same container as used in Reference Example 2, 100 parts of the polyester resin obtained in Reference Example 1, 6.8 parts of dimethylethanolamine, and 503 parts of deionized water were charged, and the temperature was raised while stirring. The temperature was set to 80℃. After adding 72 parts of the following initiator solution to this, dropwise addition of the following monomer mixture was immediately started. Initiator solution Azobiscyanovaleric acid 8 parts Deionized water 80 parts Dimethylethanolamine 8 parts Monomer mixture Methyl methacrylate 80 parts n-Butyl acrylate 130 parts Styrene 80 parts 2-Hydroxyethyl acrylate 50 parts Glycidyl methacrylate 18.5 parts 11.5 parts of methacrylic acid After finishing dropping in 2 hours, remove the remaining initiator solution.
24 parts were added and stirring was continued for 30 minutes to complete the reaction. The particle size of the microgel dispersion in the obtained emulsion was 0.042μ. This emulsion was spray-dried to obtain fine polymer particles. Reference Example 4 Production of film-forming acrylic resin varnish: 710 parts of toluene and 20 parts of n-butanol were charged into a container equipped with a stirrer, a temperature controller, and a reflux condenser. Next, 200 parts of a solution having the following composition was added and heated while stirring to raise the temperature. Methacrylic acid: 12 parts Styrene: 264 parts Methyl methacrylate: 264 parts , then azobisisobutyronitrile 3
and 100 parts of toluene were added dropwise over 30 minutes. The reaction solution was further stirred and refluxed for 2 hours to increase the conversion rate to resin, and then the reaction was terminated to obtain an acrylic resin varnish with a non-volatile content of 50%. Reference Example 5 Production of alkyd resin varnish Raw materials having the following composition were charged into a container equipped with a stirrer, a temperature control device, and a decanter, and heated while stirring. Dehydrated castor oil 260 parts Coconut oil 192 parts Trimethylolpropane 403 parts Diethylene glycol 65 parts Phthalic anhydride 578 parts Value 100
Heating was continued until the reaction was completed. The resulting resin was diluted with xylene to a nonvolatile content of 70% to obtain an alkyd resin varnish. This varnish had a Gardner viscosity of Z. Reference Example 6 Production of polyester resin varnish The following raw materials were charged into a container equipped with a stirrer, a temperature control device, and a decanter, and heated while stirring. Ethylene glycol 39 parts Neopentyl glycol 130 parts Azelaic acid 236 parts Phthalic anhydride 186 parts Continued. Then the temperature was cooled to 140℃,
Argyura E-10 (manufactured by Ciel, epoxy resin)
314 parts were added and stirring was continued for 2 hours to complete the reaction. The obtained resin has an acid value of 9, a hydroxyl value of 90,
The number average molecular weight was 1050. The non-volatile content of this resin
The mixture was diluted with xylene to a concentration of 60% to obtain a polyester resin varnish having a Gardner viscosity of Y. Example 1 Materials having the following composition were weighed into a stainless steel container and stirred using a laboratory stirrer to prepare a coating composition.

[Table] The number of fine particles dispersed in the composition of this example is 72
No sedimentation was observed even after standing for some time. When each composition was diluted with a mixed solvent of xylene/ethylene glycol monobutyl ether = 1/1 and adjusted to a viscosity of 25 seconds using a food cup No. 4, the nonvolatile content of the composition of this example was 42.3%. but,
The nonvolatile content of Comparative Example 1 was 37.6%. Furthermore, the coatings of this example exhibited much better sagging during spray coating than those of the comparative examples. Example 2 Using the same method as in Example 1, a coating composition having the following composition was prepared.

[Table] Compositions Each composition was diluted with a mixed solvent of xylene/ethylene glycol monobutyl ether = 1/1 and adjusted to a viscosity of 40 seconds using a food cup No. 4. The coating of this example was much better than that of Comparative Example 2 in terms of pin-sag performance and metal pattern control when applied using a normal spray gun. Example 3 100 parts of the alkyd resin varnish of Reference Example 5 and 100 parts of the rutile-type titanium oxide pigment were weighed into a dispersion container, and
A white paste was prepared by mixing and dispersing using a paint conditioner. A coating composition having the following formulation was prepared using this paste.

[Table] Min
p〓Toluenesulfonic acid 0.1 part 0.1 part Each composition was adjusted to a viscosity of 25 seconds using a No. 4 Folk Cup, and after spray painting using a conventional method (same speed, same interval), baking was performed at 140℃ for 30 minutes. As a result, a coating film of 47μ was obtained with the composition of this example, and a coating film with a thickness of 34μ was obtained with the composition of Comparative Example 3. Example 4 100 parts of the polyester resin varnish of Reference Example 6 and 90 parts of the rutile titanium oxide pigment were weighed into a dispersion container, and mixed and dispersed using a paint conditioner to prepare a white paste. Using this paste, a coating composition having the following formulation was prepared.

[Table] Trimerized products of each composition xylene/butyl acetate = 1/1
Dilute with thinner and add 25% with food cup No. 4.
Adjusted to a viscosity of seconds. After conventional spray painting, 80
A coating film was obtained by drying at ℃ for 30 minutes. Pins when painting
The coating of this example was far superior to that of Comparative Example 4 in terms of sagging properties and coating film thickness.

[Claims]

1. A coating composition comprising a prepolymer of aromatic polyisocyanate and polyol having an isocyanate group at the end, blocked with a lactam blocking agent, and polyaminopolyamide.

Claims (1)

A group consisting of alkyd resins, polyester resins, acrylic resins, modified epoxide resins, and polyether resins, each having a group represented by -COOH or _-SO3H (Y is a -COOH or -SO3H group) and a polymerizable α,β-unsaturated bond. obtained by copolymerization of two or more α,β-ethylenically unsaturated monomers in an aqueous or organic medium in the presence of a resin selected from Crosslinked by the presence of a monomer having two or more radically polymerizable ethylenically unsaturated groups, or two types of ethylenically unsaturated monomers each carrying mutually reactive groups. with an average particle size of 0.02
The crosslinked vinyl copolymer fine particles have a particle size of ~40μ, and the polymer components consist of 50 to 99.5 parts by weight of film-forming polymer (A) and 50 to 0.5 parts of polymer fine particles (C), and a crosslinking agent. (D) is 5 to 100 parts by weight per 100 parts by weight of polymer components (A) + (C), and an organic liquid diluent
(B) is the total amount of polymer component and crosslinking agent (A) + (C) + (D) 100
A coating composition characterized in that the ratio is 10 to 2000 parts by weight per part by weight.