JP2730364B2 - Anionic electrodeposition paint and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an anionic electrodeposition paint having high weather resistance.

[0002]

2. Description of the Related Art Conventionally, in coating aluminum materials for building materials such as aluminum sashes and curtain walls of ordinary houses and buildings, a coating material in which an amino resin such as melamine resin is mixed as a curing agent with an acrylic water-based resin has been used. This has been put to practical use by applying an anionic electrodeposition coating to an aluminum material, but in recent years, due to the demands of the times, painting with even better weather resistance has been regarded as important. Naturally, acrylic / silicone resin blends, acrylic-silicone graft copolymer resins, and fluororesins have been developed to meet this demand.

However, since the acrylic / silicone resin blend system is a blend of both resins, the silicone resin falls off in the long term, and although it is superior to the acrylic resin, it does not exhibit long-term weather resistance. In addition, acrylic-silicone-based graft copolymer resins often fail to effectively carry out the graft copolymerization reaction between acrylic and silicone resin in the reaction process, and are generally more effective than acrylic / silicone resin blends. Although excellent, long-term weatherability still has problems. Fluorine-based resins are economically disadvantageous and have poor versatility, although their performance is sufficient. In recent years, there has been an increasing demand for a matte painted surface capable of producing a more calm atmosphere than the metallic glossiness of the painted surface.
Electrodeposition paints for single-coat finishes that provide this matte coating surface are also being actively developed, but at present the development of inexpensive materials having high weather resistance and matting properties, such as fluororesins, is underway. Not.

[0004]

DISCLOSURE OF THE INVENTION The present invention overcomes the drawbacks of the above-mentioned conventional anionic electrodeposition paints and provides a polymerizable unsaturated paint.
Copolymerizable mixed monomer containing carboxylic acid monomer as one component and azo group
Silicone units derived from polysiloxane compounds
And to provide a method for producing an anionic electrodeposition coating material having excellent adhesion, weather resistance, and anti-glare property in which the anion electrodeposition paint is efficiently bonded . Copolymerization using polymerizable unsaturated acid monomer as one component
From an ionic mixed monomer and an azo group-containing polysiloxane compound
Weather resistance that efficiently combines with the led silicone unit
It is another object of the present invention to provide a method for producing an anionic electrodeposition paint having excellent matting properties .

[0005]

According to the present invention, there is provided a method for producing an anionic electrodeposition paint capable of achieving the above object.

That is, a first aspect of the present invention is to provide a copolymer derived from a polymerizable unsaturated acid monomer (a) and a monomer mixture of the polymerizable unsaturated monomer (b) copolymerizable therewith. The present invention relates to a dispersion-type anionic electrodeposition coating material containing, as a main component, an aqueous hydrate of a block copolymer having a main unit comprising a united unit (A) and a polysiloxane unit (B) derived from an azo group-containing polysiloxane compound. >

A second aspect of the present invention is a compound represented by the general formula [I]:

[0008]

Embedded image

Wherein R ₁ is an alkyl group, R ₂ is an alkyl group or a cyano group, R ₃ is an aliphatic hydrocarbon, an aliphatic amide, an amidine, an aliphatic amidine or a derivative thereof, and R ₄ is a saturated group. Or an unsaturated aliphatic, alicyclic, or aromatic hydrocarbon group, R ₅ represents a polysiloxane-containing compound group, and X and Z each represent an ester, amide, urethane or urea bond]. In the presence of 2 to 60% by weight of the polysiloxane compound, 40 to 40% of a mixed monomer of the polymerizable unsaturated acid monomer (a) and the polymerizable unsaturated monomer (b) copolymerizable therewith. 2. A method for producing a dispersion-type anionic electrodeposition coating material according to claim 1, wherein 98% by weight is radically polymerized in a hydrophilic solvent, neutralized with ammonia and / or amines, and then made aqueous.

Hereinafter, the present invention will be described in more detail. The present invention relates to a copolymer unit (A) derived from a mixed monomer of a polymerizable unsaturated acid monomer (a) and a polymerizable unsaturated monomer (b) copolymerizable therewith, Each unit with the polysiloxane unit (B) derived from the group-containing polysiloxane compound is mainly AB, ABA and / or-(AB)
_{The present} invention relates to a dispersion-type anionic electrodeposition coating material containing, as a main component, an aqueous hydrate of a block copolymer bonded to _n-, and a method for producing the azo group-containing polysiloxane represented by the general formula [I] A block copolymer solution obtained by heating and reacting the components (a) and (b) in a hydrophilic solvent using a compound is neutralized with ammonia and / or amines, and then deionized water is added. A method of adding an aqueous solution is used to obtain a resin for anionic electrodeposition paint as a stable fine particle dispersion.

The azo group-containing polysiloxane compound represented by the above general formula [I] used for producing the block copolymer includes an azo component (c), a diisocyanate or acid halide component (d), and a polysiloxane component (e). ) Can be produced by reacting

The azo component (c) has the general formula [II]

[0013]

Embedded image

An azodiol or azodiamidine compound represented by the formula:
-Azobis (2-cyanopropal), 2,2'-azobis (2-cyanobutanol), 2,2'-azobis
(2-cyanopentanol), 2,2'-azobis (2-
Cyanohexanol), 2,2'-azobis (2-methylpropanol), 2,2'-azobis (2-phenylpropanol), 2,2'-azobis [2-methyl-N-
(2-hydroxyethyl) propionamide], 2,2 '
-Azobis [2-methyl-N- (3-hydroxypropyl) propionamide], 2,2'-azobis [2-methyl-N- (7-hydroxyheptyl) propionamide], 2,2'-azobis [2 -Phenyl-N- (2-
Hydroxyphenyl) propionamide], 2,2'-
Azobis [2-methyl-N- (2-hydroxyethyl)
Propionamidine], 2,2'-azobis [2-methyl-N- (3-hydroxypropyl) propionamidine], 2,2'-azobis [2-methyl-N- (2-hydroxypropyl) propionamidine] and Azodiols such as halides; 2,2'-azobis (2-
Methylpropionamidine), 2,2'-azobis (2
-Methyl-N-phenylpropionamidine), 2,
2'-azobis [N- (4-chlorophenyl) -2-methylpropionamidine], 2,2'-azobis (N,
N'-dimethyleneisobutylamidine), 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane], 2,2'-azobis [2- (3,4,5,
6-tetrahydropyrimidin-2-yl) propane],
2,2'-azobis [2- (4,5,6,7-tetrahydro-1H-1,3-diazepin-2-yl) propane], 2,2'-azobis [N- (4-aminophenyl) -2-methylpropionamidine] and azodiamidines such as halides thereof.

The diisocyanate or acid halide is represented by the general formula [III]

[0016]

Embedded image DR ₄ -D [III]

Wherein R ₄ is the same as above, and D is N
CO, -COCl].

Specific examples of the diisocyanate include aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate and trimethylhexane diisocyanate; isophorone diisocyanate, methylcyclohexane-2,4-diisocyanate, methylcyclohexane-2,6-diisocyanate, Cycloaliphatic diisocyanates such as 4,4'-methylenebis (cyclohexylisocyanate) and 1,3-di (isocyanatomethyl) cyclohexane; or tolylene diisocyanate, xylylene diisocyanate,
And aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate.

Specific examples of the acid halide include dichlorides of saturated aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid and sebacic acid and derivatives thereof;
Dichlorides of alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid and cyclopentanedicarboxylic acid and derivatives thereof; isophthalic acid, terephthalic acid, 2,2'-diphenyldicarboxylic acid, 3,3'-diphenyldicarboxylic acid, 4,4'- Diphenyldicarboxylic acid, diphenylmethanedicarboxylic acid, 1,4-naphthalenedicarboxylic acid,
2,6-naphthalenedicarboxylic acid, 3,3'-diphenyl ketone dicarboxylic acid, 4,4'-diphenyl ketone dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl thioether dicarboxylic acid,
Dichlorides of aromatic dicarboxylic acids such as 4,4'-diphenylsulfone dicarboxylic acid and derivatives thereof; dichlorides of unsaturated aliphatic dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid and itaconic acid.

The polysiloxane component (e) has the general formula [I
V]

[0021]

Embedded image GR ₅ -G [IV]

Wherein R ₅ is the same as above, and G is-
Represented by represents OH or -NH _2], the general formula (V)

[0023]

Embedded image

Wherein R ₆ is the same or different and is a lower alkyl group, R ₇ is the same or different and is a halogen-substituted or unsubstituted alkyl or phenyl group, and J is
(CH ₂ ) _l (where l is the same or different and is 0 or 1 to 1)
6) or — (CH ₂ ) ₃ O (CH ₂ ) ₂ —, and m
Represents 0 or an integer of 1 to 200, and G is the same as described above].

In the above formula [V], the lower alkyl group means a straight or branched C1-C6 group such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl, pentyl and hexyl. Alkyl group. Further, as the halogen-substituted alkyl group, those in which the above alkyl group is halogenated, for example, chloromethyl, bromomethyl, trifluoromethyl, 2-chloroethyl, 3-chloropropyl, 3-bromopropyl,
3,3,3-trifluoropropyl, 1,1,2,2-tetrahydroperfluorooctyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine element.

The synthesis of the azo group-containing polysiloxane compound represented by the general formula [I] is performed by the azo component (c) represented by the general formula [II] and the diisocyanate or acid halide component represented by the general formula [III]. (D) and the reaction of the polysiloxane component (e) represented by the general formula [IV] or [V]. The charging ratio of each component is as follows: component (d) = component (c) + component (e) ), But it is particularly preferable that component (c): component (d): component (e) = 1: 2: 1.

The specific combinations of the components are as follows:
There are three methods, 1 of which is azodiol of component (c), diisocyanate of component (d) and component (e), and 2 of which is azodiol of component (c), acid halide and component of component (d). (E), 3 of which is component (c)
Azodiamidine, component (d) diisocyanate and component (e), and No. 4 is component (c) azodiamidine, component (d) acid halide and component (e). The order of addition of the components (c), (d) and (e) during the synthesis is not particularly limited, and the following three methods can be basically mentioned. The first is a method of reacting the component (c) with the component (d) and then reacting the component (e) to obtain an azo group-containing polysiloxane compound. The second is a method of reacting the component (d) with the component (e) and then reacting the component (c) to obtain an azo group-containing polysiloxane compound. Part 3 includes component (c), component (d) and component (e)
This is a method for obtaining an azo group-containing polysiloxane compound by simultaneously reacting.

As the organic solvent used for synthesizing the azo group-containing polysiloxane compound, an aprotic solvent is preferable, and specific examples thereof include ethers such as diethyl ether, dimethoxyethane and tetrahydrofuran; carbon tetrachloride, chloroform, Halogenated hydrocarbons such as methylene chloride and tricrene; aliphatic, alicyclic and aromatic hydrocarbons such as n-hexane, cyclohexane, benzene and xylene; acetonitrile, N, N-dimethylformamide, and N-methyl- 2-pyrrolidone and the like.

In the synthesis of the azo group-containing polysiloxane compound, a catalyst is used if necessary. in this case,
Examples of catalysts used when using diisocyanate as component (d) include organometallic catalysts such as dimethyltin dilaurate, dibutyltin dilaurate, dibutyltin di (2-ethylhexoate); triethylenediamine, triethylamine, N, Aliphatics such as N, N ', N', N "-pentamethyldiethylenetriamine, N, N-dicyclohexylmethylamine and N-methylmorpholine;
Alicyclic and heterocyclic tertiary amine catalysts are exemplified.
The catalyst used when using an acid halide as the component (d) is preferably a basic catalyst, and specific examples thereof include aliphatic compounds such as triethylamine, tributylamine, N, N-dimethylaniline, piperidine, pyridine and morpholine.
Aromatic and heterocyclic tertiary amines are included.

The reaction temperature is usually -10 to 50 ° C. in order to prevent thermal decomposition of the azo group during the reaction and side reactions between the components.
But more preferably 0 ° C to 30 ° C.
° C. If the reaction temperature is lower than −10 ° C., the reaction rate is low, which is not preferable. This causes problems such as gelation.
The reaction time is not particularly limited, but is preferably 0.5 to 24 hours.

The number average molecular weight of the azo group-containing polysiloxane compound represented by the general formula [I] is usually from 1,500 to
100,000, preferably 2,000-60,
000. If the number average molecular weight is less than 1,500, there will be considerable molecules that do not substantially possess an azo bond, so that the efficiency of block copolymerization with a polymerizable monomer is reduced, and the original function is lost. No longer shown. Conversely 10
If it exceeds 000, the solubility in the hydrophilic solvent used for block copolymerization decreases, and the solution viscosity increases, so that block copolymerization must be performed at a low concentration. For this reason, the polymerization rate of the polymerizable monomer used in the step (1) decreases, so that a long-time reaction is inevitable.

The properties of the azo group-containing polysiloxane compound thus obtained vary depending on the molecular weight and type of each component to be used, but usually exhibit a colorless to brown powder , viscous oil or rubber. ing.

Next, a copolymer unit (A) derived from a mixed monomer of a polymerizable unsaturated acid monomer (a) and a polymerizable unsaturated monomer (b) copolymerizable therewith, The production of an aqueous product of a block copolymer having a polysiloxane unit (B) derived from an azo group-containing polysiloxane compound in the main chain will be described.

The amount of the azo group-containing polysiloxane compound used for producing the aqueous hydrate of the block copolymer is 2
-60% by weight, preferably 5-30% by weight. If the amount of the azo group-containing polysiloxane compound is less than 2% by weight, block copolymerization becomes extremely difficult, and if it exceeds 60% by weight, the molecular weight of the block copolymer decreases, which is not preferable, and the economic efficiency also decreases.

It is needless to say that the polymerizable unsaturated acid monomer (a) used in the production of the block copolymer is necessary in the step of making the produced block copolymer aqueous or anionic electrodeposition coating. . Specific examples of the polymerizable unsaturated acid monomer that can be used include (meth) acrylic acid, maleic acid, fumaric acid, and itaconic acid, and these can be used alone or in combination.

The usable (a) includes acid phosphooxyethyl (meth) acrylate, acid phosphooxypropyl (meth) acrylate, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, and acid phosphooxypolyoxypropylene. Unsaturated organic phosphoric acid such as glycol mono (meth) acrylate; vinyl sulfonic acid, 2-acrylamide-2
And unsaturated organic sulfonic acids such as -methylpropanesulfonic acid and p-styrenesulfonic acid. Among these polymerizable unsaturated acid monomers (a), the use of (meth) acrylic acid is particularly preferred.

The amount of the polymerizable unsaturated acid monomer (a) varies depending on the monomer composition (b) to be copolymerized and its molecular weight and distribution, or reaction conditions. At 1
It should be adjusted between 5 and 150, preferably between 20 and 100.

Specific examples of the polymerizable unsaturated monomer (b) used for producing the block copolymer include (meth) acrylates having 1 to 8 carbon atoms, for example, methyl (meth) acrylate, Ethyl, isopropyl, n-butyl,
Isobutyl, 2-ethylhexyl, 2-hydroxyethyl, hydroxypropyl: vinyl esters of alkanemonocarboxylic acids having 1 to 12 carbon atoms, such as vinyl acetate, vinyl propionate, vinyl-n-butyrate, vinyl versatate: unsaturated Amides or imides such as (meth) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide,
N-methylol (meth) acrylamide, alkoxymethyl (meth) acrylamide such as N-butoxymethyl (meth) acrylamide, maleic imide, maleic diamide: vinyl aromatic monomer such as styrene, p
-Methylstyrene and the like. In general, any monomer having radical polymerizability can be used as the monomer of the present invention, and halogen-containing vinyl compounds such as vinyl chloride, vinylidene chloride, and vinylidene fluoride: ethylene, 1, Mono- or diolefins such as 3-butadiene: α-β olefinically unsaturated acids such as maleic acid and fumaric acid; and other (meth) acrylonitrile. These monomers can be used alone or in combination.

The amount of the mixed monomer containing the polymerizable unsaturated acid monomer (a) and the polymerizable unsaturated monomer (b) is 40
９８98% by weight, preferably 70-95% by weight. When the amount of the mixed monomer used is less than 40% by weight, the molecular weight of the block copolymer decreases, which is not preferable. When the amount of the mixed monomer is more than 98% by weight, the synthesis of the block copolymer is difficult. Extremely difficult.

Specific examples of the hydrophilic solvent used for producing the block copolymer include monoalcohols having 1 to 4 carbon atoms, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butyl alcohol,
Isobutyl alcohol and t-butyl alcohol: ethylene glycol and its derivatives such as monomethyl ether, monomethyl ether acetate, monoethyl ether, diethyl ether, monoethyl ether acetate, monoisopropyl ether of ethylene glycol,
Monobutyl ether, diethyl ether, monoethyl ether acetate, monoisopropyl ether, monobutyl ether acetate: diethylene glycol and derivatives thereof, for example, monomethyl ether, monoethyl ether, monoethyl ether acetate of diethylene glycol, mono-n-butyl ether, mono-t-butyl ether , Dimethyl ether, methyl ethyl ether,
Diethyl ether monoacetate: triethylene glycol and its derivatives, for example, monomethyl ether of triethylene glycol, monoethyl ether: propylene glycol and its derivatives, for example, monomethyl ether, monoethyl ether, mono-ethyl of propylene glycol
n-butyl ether, mono-t-butyl ether, methyl ether acetate: dipropylene glycol and its derivatives, for example, monomethyl ether of dipropylene glycol, monoethyl ether: tripropylene glycol and its derivatives, for example, monomethyl ether of tripropylene glycol: glycerin and Derivatives thereof, such as glycerin monoacetate: trimethylene glycol and its derivatives, such as 1-butoxy-ethoxypropanol, 3,3-dimethyl-3-methoxypropanol, 3-methoxybutyl acetate: butanediol and its derivatives, such as 3- Methoxybutanol, 3-
Methyl-3-methoxybutanol, 3-methyl-3-methoxybutyl acetate, 3-methyl-1,3-butanediol: an acetylene glycol derivative such as 2,
4,7,9-Tetramethyl-5-decyne-4,7-diol and its ethylene oxide adduct, 2,6-dimethyl-4-octyne-3,6-diol: other dioxane, 1,5-pentanediol Hexylene glycol, trimethylolpropane, 1,2,6-hexanetriol and low molecular weight polyethylene glycol, and the like. Generally, monoalkyl ethers of ethylene glycol or propylene glycol and monoalcohols having 5 or less carbon atoms are used in combination. It is suitable. These solvents can be used alone or in combination.

The neutralizing agent used in the production of the aqueous hydrate of the block copolymer is ammonia and / or amines. Specific examples of the amines that can be used include alkylamines such as diethylamine, triethylamine, diisopropylamine and trimethylamine; Alkanolamines such as diethanolamine and triethanolamine; and alkylalkanolamines such as dimethylaminoethanol. The amount used varies depending on the concentration (oxidation) of the polymerizable unsaturated acid monomer used, but is usually 5 to the acid group.
0 to 95 mol%.

The method for producing a block copolymer with an unsaturated monomer having a polysiloxane unit in the main chain is different from the method employed in ordinary anionic electrodeposition coatings, and is different from the above-mentioned azo group-containing polymer. Since a siloxane compound is used, a generally used low molecular weight polymerization initiator is not required. That is, the azo group-containing polysiloxane compound is dissolved in the hydrophilic solvent, the polymerizable unsaturated acid monomer (a) and the polymerizable unsaturated monomer (b), and then the temperature is raised. The azo group contained in the siloxane compound is decomposed, and the generated carbon radical becomes a site for initiation of polymerization. Therefore, a polymerization reaction of the unsaturated monomer occurs from both ends of the extended molecule of the polysiloxane unit.

The method of charging the raw materials may be either batch charging or split charging, and the reaction temperature is usually 60 to 140.
C., the reaction time is about 4 to 20 hours. In addition,
When the concentration of the azo group-containing polysiloxane compound is low, and when the molecular weight of the polysiloxane unit in the azo group-containing polysiloxane compound is high, the concentration of the azo component of the azo group-containing polysiloxane compound included in the reaction system as a whole decreases. As a result, the polymerization rate may decrease. In such a case, a normal peroxide-based and / or azo-based initiator can be added in the latter half of the polymerization reaction to improve the polymerization rate.

Specific examples of the peroxide-based initiator include methyl ethyl ketone peroxide, lauroyl peroxide, benzoyl peroxide, cumene hydroperoxide and t-butyl hydroperoxide. Specific examples of the azo initiator include:
Examples thereof include 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), and azodiol or azodiamidine compounds represented by the above general formula [II]. Further, if necessary, octyl mercaptan, lauryl mercaptan, β
-Various chain transfer agents such as mercaptopropionic acid and octyl thioglycolate can also be used for controlling the molecular weight.

The block copolymer thus obtained is neutralized with ammonia and / or amines, and then made aqueous by adding deionized water, to obtain a stable fine particle dispersion (resin for anionic electrodeposition paint). Become.

The aqueous stable dispersion of fine particles may contain, in addition to the block copolymer as the main component, chain transfer by a solvent during the reaction, or chain transfer by a chain transfer agent when a chain transfer agent is used. As a result, a copolymer derived from only a mixed monomer of the monomers (a) and (b), which does not become a block copolymer, is produced. Also, when a normal peroxide-based or azo-based initiator is used in combination with an azo-containing polysiloxane compound, a block copolymer is not obtained (a).
(B) A copolymer derived from only a monomer mixture of monomers is produced. Strictly, it also includes an azo group-containing polysiloxane compound in which the azo group has been lost during the block copolymerization reaction, and an unreacted hydroxyl group-containing polydimethylsiloxane. The solid content of the water-based stable fine particle dispersion can be usually produced in the range of 20 to 40%, but the anionic electrodeposition paint is usually prepared to a concentration of about 10% including the curing agent component. The hardener added and mixed after the production of the block copolymer may be added either before or after adding deionized water to make it aqueous.

[0047]

The present invention will be described below in more detail with reference to examples and comparative examples. Note that “parts” in Production Examples, Examples, Comparative Examples, and Application Reference Examples are “parts by weight” unless otherwise specified.

Production Example 1 (Synthesis of azo group-containing polysiloxane compound) In a 500 ml four-necked flask equipped with a thermometer, a stirrer, a reflux condenser and a calcium chloride tube, chloroform 380 was added.
Part, 2,2'-azobis (2-cyanopropanol)
[VF-077, manufactured by Wako Pure Chemical Industries, Ltd.] 5.88
Part, a polydimethylsiloxane having a hydroxyl group at both terminals having a molecular weight of 3,200 [In the above general formula (V), R ₆ and R ₇ are methyl groups, G is a hydroxyl group, and J is — (CH ₂ ) ₂ O.
(CH ₂ ) _3- , m is an average of 40, 96 parts of KF-6002 manufactured by Shin-Etsu Chemical Co., Ltd. and triethylamine 1
After charging 2.12 parts, the mixture was homogenized with stirring and cooled with ice. Next, 47 parts of a chloroform solution containing 14.32 parts of sebacic acid dichloride was added dropwise over about one hour, and then heated at 30 ° C.
The reaction was continued for hours.

After completion of the reaction, the product solution was washed with water to remove water-soluble components such as triethylamine hydrochloride contained in the solution, and dried under reduced pressure to obtain a polymer. The yield of the polymer was 93%, and the number average molecular weight in terms of polystyrene of the polymer determined by GPC was 22,000. Note that D
The thermal decomposition temperature of the azo group determined by SC (differential scanning calorimeter) is 88.6 ° C., and its enthalpy is −38.6.
Although this was mJ / mg, this heat balance was not found in the polymer after heat treatment at 140 ° C. for 5 hours.

Production Example 2 (Synthesis of azo group-containing polysiloxane compound) Instead of 2,2'-azobis (2-cyanopropanol) used in Production Example 1, 2,2'-azobis (N, N'-
A polymer was obtained in the same manner as in Production Example 1 except that 7.5 parts of dimethyleneisobutylamidine) was used.

The yield of the polymer was 98%, and the number average molecular weight in terms of polystyrene of the polymer determined by GPC was 12,000.
Met. The thermal decomposition temperature of the azo group determined by DSC was 86.2 ° C, and its enthalpy was -88.8 m
J / mg, but this heat balance was not observed in the polymer after heat treatment at 140 ° C. for 5 hours.

Preparation Example 3 (Synthesis of azo group-containing polysiloxane compound) 140 parts of chloroform was stirred in the flask used in Preparation Example 1, 100 parts of polydimethylsiloxane having hydroxyl groups at both ends used in Preparation Example 1, 10.88 parts of tolylene diisocyanate and 0.0 of dibutyltin dilaurate
7 parts were sequentially charged and reacted at room temperature for 4 hours. next,
7.82 parts of 2,2'-azobis (N, N'-dimethyleneisobutylamidine), 140 parts of chloroform and 0.005 part of dibutyltin dilaurate were charged, and the reaction was further continued at room temperature for 23 hours. After the reaction, the product solution was washed with water and dried under reduced pressure to obtain a polymer.

The yield of the polymer was 93%, and the number average molecular weight in terms of polystyrene of the polymer determined by GPC was 14,50.
It was 0. The thermal decomposition temperature of the azo group determined by DSC was 106.2 ° C. and its enthalpy was −23.
Although it was 5 mJ / mg, this heat balance was not found in the polymer after heat treatment at 140 ° C. for 5 hours.

Production Example 4 (Synthesis of azo group-containing polysiloxane compound) Instead of 2,2'-azobis (N, N'-dimethyleneisobutylamidine) used in Production Example 3, 2,2'-azobis (2 -Cyanopropanol) was carried out in the same manner as in Production Example 3 except for using 6.13 parts, to obtain a polymer.

The yield of the polymer was 99%, and the number average molecular weight in terms of polystyrene of the polymer determined by GPC was 21,000.
It was 0. The thermal decomposition temperature of the azo group determined by DSC was 81.3 ° C., and its enthalpy was −27.4 mJ.
/ Mg, but this heat balance was not found in the polymer after heat treatment at 140 ° C for 5 hours.

Examples 1 to 5 In a 1000 ml four-necked flask equipped with a stirrer, a heat exchanger and a thermometer, an azo group-containing polysiloxane compound and a polymerizable unsaturated acid monomer were added according to the formulation shown in Table 1. And the polymerizable unsaturated monomer are charged at a time and stirred at about 100 ° C.
The solution polymerization was carried out at a temperature of 7 hours, and then a diluting solvent was added. Next, the temperature of the reaction solution was adjusted to about 60 ° C., neutralized with a neutralizer solution, and deionized water was gradually added to make the aqueous solution aqueous, thereby obtaining a stable fine particle dispersion (resin for anionic electrodeposition paint).

The obtained fine particle dispersion was added with acetic acid to precipitate a resin, and repeated dissolution / precipitation with acetone / water to remove unreacted components, followed by drying, and ¹ H-NMR and infrared absorption spectrum analysis. As a result, it was confirmed that each sample was a block copolymer having a polydimethylsiloxane unit in the main chain.

[0058]

The aqueous product of the block copolymer of the present invention with a vinyl component having a polysiloxane unit in the main chain is excellent in adhesion and weather resistance, and is used as an anionic electrodeposition paint having a matting property. Useful.

[0059]

[Table 1]

Application Reference Examples 1 to 5 and (Comparative) Reference Examples 1 to
2 Cymel as a curing agent component was added to a resin for an anionic electrodeposition paint having a water-based block copolymer having a polysiloxane unit as a main chain obtained in Examples 1 to 5 and a resin of Comparative Examples 1 to 2 as main components. 301 (water-soluble melamine resin manufactured by Mitsui Toatsu Chemicals, Inc.) was blended in accordance with the formulation shown in Table 2 and anion electrodeposition coating was carried out.

The object to be coated, the electrodeposition coating conditions, and the method of evaluating the coating film performance were performed in the following manner.

A) Aluminum plate: JIS H400
(A1050P) 1.5 × 35 × 70 mm b) Anodization: ・ Immersion in a 10% NaOH aqueous solution for 2 minutes / 60 ° C., then washing with deionized water ・ Immersion in a 15% HNO ₃ aqueous solution for 30 seconds / 25 ° C., then deionization Water washing ・ 15% H ₂ SO ₄ aqueous solution at a current of 1 A / dm ² for 30 minutes /
3) Electrodeposition coating: voltage 150V, 2 minutes / 25 ° C, distance between electrodes 150mm d) Film thickness: Using a film thickness meter (Isoscope MP2, manufactured by Helmut Fisher Co.) Measurement e) Smoothness of the coating film: The appearance of the coating film after coating is visually observed.
The appearance, irregularities, and pinholes were examined. F) Adhesion: Gobang eyes at 1 mm intervals on the coated surface (10 × 10)
And then peel off after attaching cellophane tape, and evaluate by the number of remaining coatings. G) Gloss: Gloss meter [Digital variable angle gloss meter UGV-5D,
Suga Test Machine Co., Ltd. product) to measure the specular gloss at 60 degrees g) Weather resistance: gloss retention (%) after 1000 hours of sunshine weatherometer Re) Pencil hardness: "Mitsubishi Uni" (Mitsubishi Pencil (Product) Co., Ltd.) to evaluate the hardness until the coating film is damaged. D) Alkali resistance: 24 coating films in 5% Na ₂ CO ₃ aqueous solution.
Time / 20 ° C. observing Le a state after immersion) Acid resistance: 5% H ₂ SO ₄ aqueous solution for coating 24 hours / 2
Observe the condition after immersion at 0 ℃

[0063]

[Table 2]

[0064]

The aqueous product of the block copolymer of the present invention with a vinyl component having a polysiloxane unit in the main chain is excellent in adhesion and weather resistance, and has a matting property for an anionic electrodeposition paint. Useful as a resin.

Claims (2)

(57) [Claims] 1. A copolymer unit (A) derived from a monomer mixture of a polymerizable unsaturated acid monomer (a) and a polymerizable unsaturated monomer (b) copolymerizable therewith, and azo A dispersion-type anionic electrodeposition coating composition containing, as a main component, an aqueous hydrate of a block copolymer having a polysiloxane unit (B) derived from a group-containing polysiloxane compound in a main chain. 2. A general formula [I] embedded image Wherein R ₁ is an alkyl group, R ₂ is an alkyl group or
Ano group, R ₃ is an aliphatic hydrocarbon, an aliphatic amide,
Emissions, aliphatic amidine or each group of derivatives thereof, R ₄ is
Saturated or unsaturated aliphatic, alicyclic and aromatic hydrocarbons
The group R ₅ represents a polysiloxane-containing compound group, X and
Z represents an ester, amide, urethane or urea bond
Of the azo group-containing polysiloxane compound represented by the formula
Polymerizable unsaturated acid monomer (a) in the presence of
And a mixture of the polymerizable unsaturated monomer (b) copolymerizable therewith.
40-98% by weight of the monomer is free radical in a hydrophilic solvent
Polymerized and neutralized with ammonia and / or amines
2. The dispersion type according to claim 1, wherein the dispersion type is made aqueous.
A method for producing an anionic electrodeposition paint .