JPH0570712A - In-mold coating composition - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an in-mold coating composition which is excellent in weather resistance, water resistance, chemical resistance and the like, and which can form a coating capable of one-coat finishing without intermediate coating or top coating. It is in. [Structure] (A) (i) Urethane acrylate or urethane methacrylate 10 represented by the following general formula (I)
To 70% by weight, R ₃ O- (CONHR ₁ NHCO-OR ₂ O) _m CONHR ₁ NHCO-OR ₃ ... (I) (wherein m is an integer of 1 to 10 and R ₁ is an isocyanate group of a diisocyanate compound) R ₂ is a portion of the diol compound excluding the hydroxyl group, and R ₁
Alternatively, R ₂ is one having an aliphatic ring structure, and R ₃ is a portion of the hydroxyl group-containing acrylate or methacrylate excluding the hydroxyl group. ) (Ii) 5-50% by weight of a thermoplastic polymer having a glass transition temperature of 30 ° C. or higher, and (iii) a vehicle component consisting of 25-70% by weight of a radical-polymerizable monomer, (B) a release agent and (C) An in-mold coating composition for a fiber-reinforced plastic molding, which contains a polymerization initiator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention covers surface defects such as pinholes and fiber patterns on the surface of a fiber reinforced plastic molding to improve the appearance quality, and has a durable quality such as weather resistance, water resistance and chemical resistance. The present invention relates to a one-pack type in-mold coating composition capable of improving the above properties and capable of finishing one coat.

[0002]

2. Description of the Related Art A matrix of a thermosetting resin or a thermoplastic resin such as a sheet molding compound (SMC), a bulk molding compound (BMC) and a stampable sheet is used as a matrix.
Molded products obtained from fiber-reinforced plastic molding materials such as glass fibers, carbon fibers, organic fibers, and mineral fibers are excellent in mechanical strength and moldability, and are lightweight, so they are parabona-based materials as alternatives to metals. It is widely used in the fields of electric equipment such as antennas, automobile outer panels, and housing equipment parts.

However, these molded products have surface defects such as pinholes, burrows, microcracks, and fiber patterns, and also have low gloss and poor appearance quality, and further have weather resistance, water resistance and chemical resistance. There were problems such as poor properties and low hardness. Therefore, these molded products are usually coated with a paint to form a protective coating on the surface, but since the molded products have many surface defects as described above, they can be applied to ordinary coating means such as spraying. However, there is a problem that it is difficult to form a film having an excellent appearance such as smoothness even when applied by coating, the adhesion is low, and the coating workability is poor. Therefore, an in-mold coating method has been proposed as a method for solving these problems. For example, U.S. Pat.
See 527, 4076788, 4668460, etc.

However, since this in-mold coating method is a special method, it has been difficult to use conventional coating materials as they are. Therefore, in-mold coating compositions suitable for the in-mold coating method have been developed in recent years. For example, Japanese Examined Patent Publication Sho 54-1327
No. 3, JP-B-59-15137, JP-B-59-195
See No. 83, etc. However, these in-mold coating compositions
It has a function as a primer, and it is premised that an intermediate coating and a top coating are applied on the obtained coating, and those consisting only of the coating have poor weather resistance and discoloration or chalking occurs. The water resistance was poor, the water resistance was poor, blisters were likely to occur, and the chemical resistance was poor.

The present inventors have made diligent studies in view of the present situation, and as a result, have solved the above-mentioned problems and are excellent in weather resistance, water resistance, chemical resistance, etc. Therefore, intermediate coating and top coating can be performed. The present invention has been accomplished by finding an in-mold coating composition capable of forming a coating capable of performing an unnecessary one-coat finish.

[0006]

Means for Solving the Problems That is, the present invention provides (A) (i) 10 to 70% by weight of urethane acrylate or urethane methacrylate represented by the following general formula (I), R ₃ O- (CONHR ₁ NHCO-OR ₂ O) _m CONHR ₁ NHCO-OR ₃ ... (I) (where m is an integer of 1 to 10, R ₁ is a portion excluding the isocyanate group of the diisocyanate compound, and R ₂ is the hydroxyl group of the diol compound. Part and R ₁
Alternatively, R ₂ is one having an aliphatic ring structure, and R ₃ is a portion of the hydroxyl group-containing acrylate or methacrylate excluding the hydroxyl group. ) (Ii) A vehicle component consisting of 5 to 50% by weight of a thermoplastic polymer having a glass transition temperature of 30 ° C or higher and (iii) 25 to 70% by weight of a radically polymerizable monomer, (B) a release agent and (C). The present invention relates to an in-mold coating composition for a fiber-reinforced plastic molded product, which contains a polymerization initiator.

The present invention will be described in detail below. The in-mold coating composition of the present invention contains a specific urethane acrylate or urethane methacrylate (hereinafter, acrylate or methacrylate is referred to as “(meth) acrylate”), a thermoplastic polymer, and a radical-polymerizable monomer as main components, which will be described later. A vehicle component (A), a release agent (B), and a polymerization initiator (C) as essential components, and if necessary, a modifying resin, a pigment, and other various additives. is there.

The urethane (meth) acrylate constituting the vehicle component (A) is represented by the following general formula (I). R ₃ O- (CONHR ₁ NHCO-OR ₂ O) _m CONHR ₁ NHCO-OR ₃ ... (I) (wherein m is an integer of 1 to 10, R ₁ is a portion of the diisocyanate compound excluding the isocyanate group, R ₂ is a portion of the diol compound excluding the hydroxyl group, and R ₁
Alternatively, R ₂ is one having an aliphatic ring structure, and R ₃ is a portion of the hydroxyl group-containing acrylate or methacrylate excluding the hydroxyl group. ) Urethane (meta)
Acrylate includes a diisocyanate compound, a diol compound and a hydroxyl group-containing (meth) acrylate,
It can be obtained by mixing all at once and reacting. As another method, a diol compound and a diisocyanate compound are reacted to form a urethane isocyanate intermediate containing one or more isocyanate groups per molecule, and then the intermediate and a hydroxyl group-containing (meth) acrylate are prepared. By reacting a diisocyanate compound with a hydroxyl group-containing (meth) acrylate to form a urethane (meth) acrylate intermediate containing one or more isocyanate groups per molecule, and then with this intermediate Examples thereof include a method of reacting with a diol compound.

As the diisocyanate compound, various known compounds can be used, and specific examples thereof include
1,2-diisocyanatoethane, 1,2-diisocyanatopropane, 1,3-diisocyanatopropane, hexamethylene diisocyanate, lysine diisocyanate,
Trimethylhexamethylene diisocyanate, tetramethylene diisocyanate, dimer acid diisocyanate, bis (4-isocyanatocyclohexyl) methane,
Methylcyclohexane 2,4-diisocyanate, methylcyclohexane 2,6-diisocyanate, 1,3-
Bis (isocyanatomethyl) cyclohexane, 1,3-
Bis (isocyanatoethyl) cyclohexane, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-bis (isocyanatomethyl) benzene, 1,3-bis (isocyanato-1-methylethyl) benzene Etc. can be given.

These diisocyanates may be used individually or as a mixture with one another. Among these, preferred are those having an aliphatic ring structure in the structure, and particularly preferred are 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3- It is bis (isocyanatomethyl) cyclohexane or bis (4-isocyanatocyclohexyl) methane.

Specific examples of the diol compound include alkyl diols, polyether diols and polyester diols. Examples of the alkyl diol include ethylene glycol, 1,3-propanediol, propylene glycol, 2,3-butanediol, 1,4-butanediol, 2-ethylbutane-1,
4-diol, 1,5-pentadiol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-
Decanediol, 1,9-decanediol, 1,4-cyclohexanediol, 1,4-dimethylolcyclohexane, 4,8-dihydroxytricyclo [5.2.
1.0 ^2,6 ] decane, 4,8-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, 2,2
-Bis (4-hydroxycyclohexyl) propane,
2,2-diethylpropane-1,3-diol, 2,2
-Dimethylpropane-1,3-diol, 3-methylpentane-1,4-diol, 2,2-diethylbutane-
1,3-diol, 4,5-nonanediol, and 2
-Butene-1,4-diol and the like.

As the polyether diol, those synthesized by polymerization of aldehyde, alkylene oxide or glycol by a known method can be used, for example, formaldehyde, ethylene oxide, propylene oxide, tetramethylene oxide, epichlorohydrin and the like. There can be mentioned a polyether diol obtained by addition-polymerizing an alkyl diol under appropriate conditions.

The polyester diols include esterification reaction products obtained by reacting saturated or unsaturated dicarboxylic acids and / or their acid anhydrides with excess alkyl diols, and alkyl diols with hydroxycarboxylic acids. And / or an esterification reaction product obtained by polymerizing lactone which is an internal ester thereof and / or lactide which is an intermolecular ester can be used.

Examples of the saturated or unsaturated dicarboxylic acid include oxalic acid, malonic acid, succinic acid, methylsuccinic acid, 2,3-dimethylsuccinic acid, hexylsuccinic acid, glutanoic acid, 2,2-dimethylglutaric acid, 3,3
-Dimethyl glutaric acid, 3,3-diethyl glutaric acid,
Adipic acid, pimelic acid, suberic acid, azelaic acid,
Sebacic acid, 1,2-cyclohexanedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, maleic acid, fumaric acid, aconitic acid, itaconic acid, Mention may be made of citraconic acid, mesaconic acid, muconic acid and dihydromuconic acid and halo and alkyl derivatives of the above acids.

Examples of the hydroxycarboxylic acid include lactic acid, glycolic acid, α-hydroxyllacic acid, β-hydroxyllacic acid, α-hydroxyisolacic acid, hydroxystearic acid, resinolenic acid and γ-hydroxyvaleric acid. The diol compounds listed above may be used alone or as a mixture with each other.

Among the above-mentioned diol compounds, preferred are those having an aliphatic ring structure in their structure, and particularly preferred are 4,8-bis (hydroxymethyl) tricyclo. [5.2.1.0 ^2,6 ] decane, 2,2-bis (4-hydroxycyclohexyl)
It is propane or a polyether polyol obtained by adding alkylene oxide to these or a polyester polyol obtained by adding a lactone.

The urethane (meth) acrylate used in the present invention is required to have an aliphatic ring structure in its structure in order to improve the adhesion of the resulting coating film to a molded article and the weather resistance. And therefore,
As described above, at least one of the diisocyanate compound and the diol compound having an aliphatic ring structure is used. As the hydroxy group-containing acrylate, various known ones may be used, and specific examples thereof include 2
-Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, 3-bromo-2-hydroxypropyl (meth) Acrylate, 2-chloro-
Examples thereof include 1- (hydroxymethyl) ethyl (meth) acrylate and 2-bromo-1- (hydroxymethyl) ethyl (meth) acrylate.

The urethane (meth) acrylate used in the present invention has a structure represented by the above general formula (I) obtained by reacting the above-described diisocyanate compound, diol compound and hydroxyl group-containing (meth) acrylate. Have, where m is 1
It is an integer from 10 to 10, and when m is larger than 10, the curability of the coating composition is deteriorated and the toughness of the obtained coating is deteriorated.

The above-mentioned thermoplastic polymer constituting the vehicle component (A) is blended in order to improve the adhesion of the resulting coating film to the molded product, and specifically, acrylic polymer, polyester polymer and the like. However, the polymers are not limited to these. As the acrylic polymer, those obtained by polymerizing various known acrylic monomers by various known methods can be used. Examples of the acrylic monomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl ( Examples thereof include (meth) acrylate, butyl (meth) acrylate, and hydroxyethyl (meth) acrylate. Further, vinyl monomers such as styrene, vinyltoluene and vinyl acetate can be copolymerized with the acrylic polymer. Examples of the polyester-based polymer include saturated or unsaturated dicarboxylic acids and / or their acid anhydrides described in the specific examples of the polyester polyol, and alkyls described in the specific examples of the polyester diol. An esterification reaction product obtained by reacting with a diol can be mentioned.

It is necessary to use a thermoplastic polymer having a glass transition temperature of 30 ° C. or higher, and if it is lower than that, the heat resistance of the obtained coating film is lowered, which is not preferable.
The radical-polymerizable monomer that constitutes the vehicle component (A) has a function as a viscosity adjusting agent for adjusting the viscosity of the coating composition to be suitable for injecting into the mold described below, and the urethane (meta) ) It is compounded for radical polymerization with the polymerizable unsaturated group in the acrylate to form a uniform cured film.

Examples of radically polymerizable monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate,
2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-dicyclopentenoxyethyl (meth) acrylate, methoxy Ethyl (meth) acrylate, ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxyethoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) )
Acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate,
(Meth) acrylic acid, (meth) acrylate monomers such as (meth) acryloylmorpholine, and styrene, vinyltoluene, N-vinyl-2-pyrrolidone, N-vinylimidazole, N-vinylcaprolactam, allyl acetate, vinyl acetate, propion Vinyl monomers such as vinyl acrylate and vinyl benzoate can be used.

Further, in order to improve the performance such as the curing speed and coating hardness of the coating composition, a polyfunctional (meth) acrylate can be used as a radically polymerizable monomer.
Specific examples of the polyfunctional (meth) acrylate include trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, triallyl cyanurate, triallyl isocyanurate, triallyl formal, (1, 3, 5 -Triacryloylhexahydro-S-triazine), polypropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate and the like.

The vehicle component (A) is composed of the urethane (meth) acrylate, the thermoplastic polymer and the radical-polymerizable monomer described above. In addition,
Urethane (meth) acrylate is a vehicle component (A)
The content of 10 to 70% by weight is suitable, and if it is less than the above range, the hardness of the obtained coating becomes difficult to obtain, the chemical resistance and water resistance are lowered, and the adhesion to the molded article is also lowered. On the other hand, when the amount is more than the above range, the viscosity of the coating composition becomes high, the dispersibility of the pigment described below decreases, and the fluidity when injected into the mold tends to decrease. Neither is preferable. A particularly preferred range is 25 to 50% by weight.

It is appropriate that the thermoplastic polymer is blended in the vehicle component (A) in an amount of 5 to 50% by weight. If the amount is less than the above range, the adhesiveness of the resulting coating film to the molded product tends to decrease. On the other hand, if the amount is more than the above range, the hardness of the obtained coating tends to be low, and the chemical resistance, water resistance and the like tend to be lowered, so that both are not preferable.
A particularly preferred range is 10 to 30% by weight.

Further, it is appropriate that the radical-polymerizable monomer is blended in the vehicle component (A) in an amount of 25 to 70% by weight. If the amount is less than the above range, the viscosity of the coating composition becomes high and the monomer is injected into the mold. In addition, the fluidity at the time decreases, and the impact resistance also decreases. On the other hand, if the amount exceeds the above range, warpage occurs in the molded product due to volume shrinkage during polymerization and curing, or the adhesiveness decreases due to shrinkage stress inside the film. In addition, hardness, chemical resistance, water resistance, weather resistance, etc. are also deteriorated, which is not preferable. A particularly preferred range is 35 to 60% by weight.

The release agent (B) used in the present invention is added so that the cured coating can be released from the mold smoothly. The types thereof include zinc, aluminum, magnesium and calcium. Typical examples include stearate, lecithin, and alkyl phosphate, but the invention is not limited thereto. The release agent (B) is preferably added in an amount of 0.05 to 4% by weight in the coating composition.

The polymerization initiator (C) used in the present invention is
Free radicals are generated, the vehicle component is polymerized, and the coating is hardened to mix. As the polymerization initiator, tertiary butyl perbenzoate, tertiary butyl peroctoate, methyl ethyl ketone peroxide, tertiary benzyl perbenzoate,
Typical examples thereof include dicumyl peroxide, cumyl hydroperoxide, diacetyl peroxide, caprylyl peroxide, and tert-butyl hydroperoxide, but the present invention is not limited thereto.

The polymerization initiator (C) is preferably added in an amount of 0.1 to 5% by weight based on the vehicle component. The coating composition of the present invention contains the vehicle component (A), the release agent (B) and the polymerization initiator (C) described above as essential constituent components, and further contains a pigment, a curing accelerator, a dispersant, and a sedimentation agent if necessary. It is composed of various additives such as an inhibitor, a flow aid, a polymerization inhibitor and an ultraviolet absorber.

In the case of clear, the above-mentioned pigment is not necessarily blended, but the molded product is colored to have an aesthetic appearance, and the shrinkage stress due to film curing is dispersed to improve the adhesion to the molded product. It is desirable that the composition is blended for the purpose of filling cavities and the like existing on the surface of the molded product, smoothing fine irregularities on the surface, and further having functions such as conductivity. As the pigment, a coloring pigment or an extender pigment which has been conventionally used for plastics and paints can be used without particular limitation as long as it does not adversely affect the curability of the coating film and hardly discolors.

Specific examples of color pigments include titanium oxide for white type, benzidine yellow, titanium yellow, and Hansa yellow for yellow type; molybdate orange, yellow lead, benzidine orange for orange type; quinacridone, maroon; black type for red type. Then carbon black, powdered pigments such as iron oxide or flaky aluminum, copper,
Typical examples are scale-like pigments such as stainless steel, mica, graphite, and titanium nitride.

Typical extender pigments include calcium carbonate, talc, barium sulfate, aluminum hydroxide, clay, and various resin powders. It is possible to add an arbitrary amount of the pigment in the coating composition according to the above purpose, but it is appropriate to add up to 40% by weight in the case of a normal coloring pigment and up to 50% by weight in the case of an extender pigment, and to use both together. If so, it is appropriate to add up to 65% by weight. Next, a method of coating the coating composition of the present invention in a mold will be described.

As the fiber-reinforced plastic molding material used in the present invention, conventionally known materials such as SMC, BMC, FRTP and stampable sheets can be used without particular limitation. Specifically, an unsaturated polyester resin system, an epoxy acrylate resin system, a phenol resin system, a thermosetting resin such as an epoxy resin system or a polyolefin resin system, a polystyrene resin system, a thermoplastic resin such as a polycarbonate resin system as a matrix, The above-mentioned fiber-reinforced plastic molding material can be mentioned as a typical example.

As a molding method, a conventional method of molding in a mold can be used without any particular limitation, but it is preferably JP-A-61-61.
-273921 and JP-B-55-9291. That is, one mold is the other mold (hereinafter, for convenience, the former is referred to as "lower mold" and the latter is referred to as "upper mold").
The above-mentioned fiber-reinforced plastic molding material is put into a mold for forming a cavity space having the shape of the target molded product by fitting it inside, and is fitted and molded in the mold. That is, when the molding material uses a thermosetting resin as a matrix, the molding material is heated and pressed to flow the molding material and cause a thermosetting reaction to mold it into a desired shape. The molding heating temperature is arbitrarily determined depending on the molding time, the type of molding material, etc., but normally 130 to 200 ° C. is appropriate, and the mold is set to the above temperature before the molding material is put in, and the cured film described later is obtained. It is desirable to maintain the temperature until the above is obtained.

The molding pressure is arbitrarily determined depending on the heating temperature, the type of molding material, etc., but usually 50 to 200 kg / cm ²
Is appropriate. The molding time may be until the thermosetting reaction of the molding material is completely completed, but when the coating composition described below is injected, it may be cured to a strength that does not impair the shape of the molding, and is usually 40 to About 200 seconds is suitable.

On the other hand, when the molding material uses a thermoplastic resin as a matrix, the material which has been heated and softened in advance by a heating oven or the like is pressed in a mold to flow the molding material and mold it into a desired shape, which will be described later. When the coating composition is injected, it is cured to such strength that the shape of the molded article is not damaged. After the molded product is cured in this manner, the upper mold is separated from the surface of the molded product and is larger than a desired cured coating film thickness to be described later, but it is not enough to release the fitting of the mold. After giving a gap, or while maintaining the molding pressure with the mold fitted, or after reducing the pressure, a desired film thickness, preferably 10 to 1000
The coating composition is injected (injection injection) between the upper mold and the surface of the molded article in such an amount that a cured coating of μm is obtained.

Next, when the molding material uses a thermosetting resin as a matrix, the coating composition uniformly covers the surface of the molding while maintaining the heating temperature at about the above temperature,
(Re) pressurize to about 10-140 kg / cm ² to penetrate,
It is usually maintained for about 30 to 120 seconds until the cured film is formed. On the other hand, when the molding material uses a thermoplastic resin as a matrix, the coating composition is uniform while maintaining the mold temperature at a temperature at which the molding does not re-soften and the coating composition cures, for example, 60 to 160 ° C. The surface of the molded article is covered with, and (re) pressurized to about 10 to 140 kg / cm ² so as to permeate, and usually maintained for about 30 to 150 seconds until a cured film is formed. In this case, it is desirable that the curing temperature of the coating composition is lower, so that a curing accelerator such as cobalt naphthenate or amine may be used in combination.

After the cured film is formed on the surface of the molded product in this manner, the mold is opened and the molded product is taken out to obtain a molded product having a protective coating.

[0038]

INDUSTRIAL APPLICABILITY The in-mold coating composition of the present invention covers surface defects such as pinholes on the surface of a fiber-reinforced plastic molded product, improves the appearance quality, and improves adhesion, weather resistance, water resistance, and
Since it can form a film with excellent chemical resistance, it has not only the function as a primer but also the function as a topcoat, and one coat can be finished. It can be said that it is.

[0039]

EXAMPLES The present invention will now be described in more detail by way of examples. In the examples, "part" and "%" are based on weight. (Preparation of Urethane (Meth) Acrylate Solution) Synthesis Examples 1-2 Total amount of components (A) to (C) in component (A) and diluent monomer (radical polymerizable monomer) in the amounts shown in Table 1 is 10
An amount of 0.02 part per 0 part of dibutyltin dilaurate was charged, the component (B) shown in Table 1 was added dropwise while keeping the temperature at 40 ° C., and the mixture was reacted for a sufficient time. Into the component (C), a solution prepared by dissolving hydroquinone in an amount of 0.1 parts per 100 parts of the total amount of the components (A) to (C) was added dropwise, and heating and stirring were continued at 75 ° C. for a sufficient time. A urethane (meth) acrylate solution (UA-1, 2) was obtained. Synthetic Examples 3 to 4 and Comparative Synthetic Example 1 In the amounts shown in Table 1, (A) was added to the component (A) and the diluted monomer.
To (C) component was added in an amount of 0.02 part per 100 parts of the total amount of dibutyltin dilaurate, and while maintaining the temperature at 40 ° C., the components (B) and (C) in the amounts shown in Table 1 were added to (A). ~ A solution of hydroquinone in an amount of 0.1 parts per 100 parts of the total amount of component (C) is added dropwise, and the mixture is further heated and stirred at 75 ° C for a sufficient time, and a solution of urethane (meth) acrylate (UA -3, 4, 5) were obtained.

[0040]

[Table 1]

A-1: 3-isocyanatomethyl-3,
5,5-trimethylcyclohexyl isocyanate A-2; bis (4-isocyanatocyclohexyl) methane A-3; 1,3-bis (isocyanatomethyl) cyclohexane A-4; bis (4-isocyanatophenyl) methane B- 1; 2,2-bis (4-hydroxycyclohexyl) propane B-2; 2,2-bis (4-hydroxycyclohexyl) propane ethylene oxide adduct (average molecular weight 1000) B-3; 2,2-bis ( Ε-caprolactone adduct of 4-hydroxycyclohexyl) propane (average molecular weight 500) B-4; ethylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane (average molecular weight 100)
0) C-1; 2-hydroxyethyl acrylate C-2; 2-hydroxyethyl methacrylate C-3; 3-hydroxypropyl acrylate (Preparation of thermoplastic polymer) Synthesis example 1 1000 parts by weight of deionized water, polyvinyl alcohol To
2.2 parts by weight are mixed and charged into a reaction vessel equipped with a cooling tube, a stirrer and a thermometer, and then methyl methacrylate 6
00 parts by weight, 400 parts by weight of butyl methacrylate, and 30 parts by weight of benzoyl peroxide were mixed and put into a reaction vessel.
The stirring speed was kept at 350 rpm, and the temperature inside the reaction vessel was raised to 88 ° C. by heating with hot water from outside the reaction vessel to start suspension polymerization. About 2 hours after the internal temperature reached 88 ° C, the internal temperature and the external temperature were reversed. Then, the internal temperature was kept at 88 ° C. for about 1 hour to complete the polymerization. Then, the resin (P-1) was obtained by cooling with water to about 40 ° C. or lower, and dried for about 24 hours. The obtained resin was white and transparent. Its Tg was 50 ° C. Synthesis Example 2 600 parts by weight of methyl methacrylate in Synthesis Example 1,
Polymerization was carried out in the same manner except that 400 parts by weight of butyl methacrylate was changed to 700 parts by weight of methyl methacrylate and 300 parts by weight of ethyl acrylate to obtain a white transparent resin (P-2). Its Tg was 55 ° C. Examples 1 to 6 and Comparative Examples 1 to 4 Components shown in Table 2 (however, excluding the polymerization initiator) were kneaded and dispersed, and the polymerization initiator was added immediately before use to prepare coating compositions A to J.
Was prepared. Using each of the obtained coating compositions, a molded product having a coating film was manufactured under the following conditions according to the molding apparatus and molding method described in JP-A-61-273921.

Using a box-type test mold having a length of 250 mm, a width of 150 mm, and a height of 50 mm, which was plated with chromium, the molding temperature was set to 150 ° C. for the upper mold and 145 ° C. for the lower mold. First, SM, which is an unsaturated polyester thermosetting glass fiber reinforced plastic molding material (glass fiber content 30%), is placed on the lower mold.
350 g of the C material was set and molded under the conditions of a molding pressure of 130 kg / cm ² and a molding time of 50 seconds.

Next, after the molding pressure was reduced, 25 g of each coating composition was poured between the upper molds to form a molding pressure of 70 kg.
Pressurized to / cm ² and maintained for 90 seconds. Next, the mold was opened and the molded product was taken out. As a result, the film (film thickness about 12
A molding covered with 0 μm) was obtained. The obtained film was subjected to performance tests of film appearance, hardness, adhesion, chemical resistance, water resistance, weather resistance and impact resistance, and the results are shown in Table 2.
It is shown in the lower column.

As is clear from the results of the performance test shown in Table 2, the coating film obtained by using the in-mold coating composition of the present invention has no appearance, and has an adhesive property, chemical resistance, water resistance, weather resistance, It was excellent in impact resistance. On the other hand, in Comparative Example 1 in which urethane (meth) acrylate having no aliphatic ring structure was used, adhesion, weather resistance and the like were poor. Further, in Comparative Example 2 in which urethane (meth) acrylate was excessively blended as the vehicle component, the film appearance was poor. Further, in Comparative Example 3 in which the thermoplastic polymer was not added, the adhesion and impact resistance were poor. Further, Comparative Example 4 in which the radical-polymerizable monomer was excessively blended had poor adhesion, water resistance, weather resistance and the like.

[0045]

[Table 2]

Note 1) Visual inspection of film appearance Pass: Smooth and uniform Fail: Abnormality of color unevenness, flow pattern, warp, etc. Note 2) Pencil hardness Note 3) Peeling test with cellophane tape on 100 2mm square squares * 4) Visual inspection of coating state after 24 hours at room temperature spot with 1N sulfuric acid solution Pass: No abnormality Fail: Abnormalities such as blisters and discoloration Note 5) Coating after immersion in water (40 ° C) for 240 hours Visual judgment of the condition Pass: No abnormality Fail: Abnormalities such as blisters and discoloration Note 6) Accelerate for 300 hours with Sanshan Weatherometer Visually judge the film state after the weather resistance test Pass: No abnormality Fail: Discoloration, blister , Gloss reduction, etc. Note 7) Visual inspection of film state after DuPont impact test (500 g / cm) Pass: No crack Fail: Crack

Front page continued (72) Inventor Masaki Shinmoto 4-1-60 Sunadabashi, Higashi-ku, Nagoya, Aichi Sanryu Rayon Co., Ltd. Product Development Laboratory (72) Inventor, Yukishige Takamatsu 4-1-1 Sunadabashi, Higashi-ku, Nagoya, Aichi 60 Sanryo Rayon Co., Ltd. Product Development Laboratory (72) Inventor Mina Obayashi 4-1-1 Sunadabashi, Higashi-ku, Nagoya, Aichi Prefecture 60-58 Sanryo Rayon Co., Ltd. Product Development Laboratory (72) Inventor Satoshi Fujii Iwaseidai, Kasugai City, Aichi Prefecture 10-18-5 (72) Inventor Kenji Yonemochi 631-1 Komatsuji, Komaki-shi, Aichi (72) Inventor Munehiro Nishimoto 2-11 Asahi-cho, Iwakura-shi, Aichi Dream Heights II Room I-B

Claims (1)

[Claims] 1. (A) (i) 10 to 70% by weight of urethane acrylate or urethane methacrylate represented by the following general formula (I), R ₃ O- (CONHR ₁ NHCO-OR ₂ O) _m CONHR ₁ NHCO-OR ₃ ... (I) (wherein m is an integer of 1 to 10, R ₁ is a portion of the diisocyanate compound excluding the isocyanate group, R ₂ is a portion of the diol compound excluding the hydroxyl group, and R ₁
Alternatively, R ₂ is one having an aliphatic ring structure, and R ₃ is a portion of the hydroxyl group-containing acrylate or methacrylate excluding the hydroxyl group. ) (Ii) A vehicle component consisting of 5 to 50% by weight of a thermoplastic polymer having a glass transition temperature of 30 ° C or higher and (iii) 25 to 70% by weight of a radically polymerizable monomer, (B) a release agent and (C). An in-mold coating composition for a fiber-reinforced plastic molded product, which comprises a polymerization initiator.