JPH06279685A - Thermosetting resin composition for in-mold coating molding and method or in-mold coating molding - Google Patents

Abstract

PURPOSE:To provide the subject composition enabling obtaining, by in-mold coating molding process, a coated molded product excellent in the adhesion of the coating layer and maintaining sufficient such adhesion even after subjected to severe environments such as cold repetition. CONSTITUTION:The objective composition is intended that a base material consisting of a thermosetting molding material is coated, in a mold, with a thermosetting coating material to form a coating layer. In this case, one party of said thermosetting molding material and thermosetting coating material is a thermosetting resin composition comprising (A) a thermosetting resin and (B) at least one kind of compound selected from unsaturated carboxylic acids, unsaturated sulfonic acids, unsaturated phosphoric acid compounds, unsaturated isocyanates and unsaturated isothiocyanates, and the other party is a second thermosetting resin composition comprising (a) a thermosetting resin and (b) at least one kind of compound selected from unsaturated phosphoric acid compounds, polyols and polymercaptans..

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an in-mold coating and molding method for forming a coating layer by coating a thermosetting coating material on a substrate made of a thermosetting molding material in a molding die. The present invention relates to a thermosetting resin composition for in-mold coating molding used as a thermosetting molding material and a thermosetting coating material, and in particular, to obtain a coated molded article having excellent adhesion between a base material made of a molding material and a coating layer. The present invention relates to a thermosetting resin composition and an in-mold coating molding method using the thermosetting resin composition, which are possible.

[0002]

2. Description of the Related Art Recently, molded articles made of thermosetting material have
It is very widely used in industrial parts as a substitute for metal parts. Above all, a sheet molding compound (hereinafter abbreviated as SMC) or a bulk molding compound (hereinafter abbreviated as BMC) is generally used.

However, in a molded product obtained by molding SMC or BMC by heating and pressing in a molding die, surface defects such as pores, microcracks, sink marks or undulations tend to occur on the surface. When such surface defects are present, it is difficult to form a sufficient coating film even if the molded product is coated by a usual method.

Therefore, a so-called in-mold coating molding method has been proposed as a method for concealing the above-mentioned surface defects. For example, Japanese Examined Patent Publication No. 4-33252 discloses a method of forming a coating layer on the surface of a molded article by injecting a coating material at an injection pressure higher than the molding pressure and curing it during compression molding.

[0005]

However, there is a problem that the coating film formed by the in-mold coating molding method does not have sufficient adhesion to the base material made of the molding material. An object of the present invention is to obtain a coated molded article having good adhesiveness of a coating layer and capable of maintaining sufficient adhesiveness even after undergoing an environmental change such as repeated cold and heat by an in-mold coating molding method. It is an object of the present invention to provide a thermosetting resin composition for in-mold coating molding, which enables the above, and an in-mold coating molding method using the same.

[0006]

According to a first aspect of the present invention, there is provided an in-mold coating for forming a coating layer by coating a thermosetting coating material on a substrate made of a thermosetting molding material in a die. A thermosetting resin composition used in a molding method, wherein one of the thermosetting molding material and the thermosetting coating material is a thermosetting resin, an unsaturated carboxylic acid, an unsaturated sulfonic acid,
A thermosetting resin composition containing at least one of an unsaturated phosphoric acid, an unsaturated isocyanate and an unsaturated isothiocyanate, the other being a thermosetting resin,
It is a thermosetting resin composition containing at least 1 sort (s) of a polyol and a polymer captan, It is a thermosetting resin composition for in-mold coating molding characterized by the above-mentioned.

Further, the invention according to claim 2 is the thermosetting molding material and the thermosetting coating material according to claim 1 in the in-mold coating molding method, respectively. It is characterized by using a material.

The details of the structure of each invention according to claims 1 and 2 will be described below. Invention of Claim 1 In invention of Claim 1, as a thermosetting resin used for a thermosetting molding material, in addition to the said polyol and polymercaptan, a heat decomposable radical catalyst is used and it is doubled. An unsaturated polyester resin having a reactive double bond in the molecule, an epoxy acrylate (vinyl ester) resin, a urethane acrylate resin, or the like, which can form a three-dimensional network structure by cleavage addition reaction of the bond, is used. These resins may be used alone or as a mixture of plural kinds.

The thermosetting resin used for the coating material is
Similarly, unsaturated polyester resin, epoxy acrylate (vinyl ester) resin, urethane acrylate resin and the like are used in addition to the above polyol and polymercaptan. These resins may be used alone or as a mixture of plural kinds.

The above-mentioned unsaturated polyester resin is usually produced by a known and commonly used method, usually an organic polyol, an aliphatic unsaturated polycarboxylic acid, and, if necessary, an aliphatic saturated polycarboxylic acid and / or an aromatic polycarboxylic acid. Manufactured from.

On the other hand, the above-mentioned epoxy acrylate (vinyl ester) resin is also produced by a known and conventional method.
Usually, it is produced from an epoxy resin and a monocarboxylic acid having a reactive double bond such as (meth) acrylic acid.

Further, the urethane acrylate resin is
Usually, it is produced by reacting an organic polyol such as an alkylene diol, an alkylene diol ester, an alkylene diol ether, a polyether polyol or a polyester polyol with an organic polyisocyanate, and further reacting with a hydroxyalkyl (meth) acrylate.

Examples of the organic polyol used in the above unsaturated polyester resin include diols, triols, tetrols, and mixtures thereof. They are mainly classified into aliphatic polyols and aromatic polyols, of which aliphatic ones. Typical examples of the polyol include ethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, triethylene glycol, neopentyl glycol, dibromoneopentyl glycol, hexamethylene glycol, trimethylene glycol, trimethylolpropane, glycerin, There are pentaerythritol diallyl ether, hydrogenated bisphenol A, etc., and typical aromatic polyols are bisphenol A or bisphenol S. Polyoxyalkylene bisphenol A or polyoxyalkylene obtained by adding an aliphatic oxirane compound such as ethylene oxide, propylene oxide or butylene oxide to these bisphenol A or bisphenol S in the range of 1 to 20 on average in one molecule. There are bisphenol S and the like.

As the aliphatic unsaturated polycarboxylic acid used in the unsaturated polyester resin, (anhydrous) maleic acid, fumaric acid, (anhydrous) itaconic acid and the like are used. The aliphatic saturated polycarboxylic acid used in the unsaturated polyester resin, sebacic acid, adipic acid,
(Anhydrous) succinic acid or the like is used.

As the aromatic polycarboxylic acid used for the unsaturated polyester resin, (anhydrous) phthalic acid, isophthalic acid, terephthalic acid, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride and the like are used.

The epoxy resin used for the epoxy acrylate (vinyl ester) resin is also a bisphenol A type epoxy resin produced from epichlorohydrin and bisphenol A, epichlorohydrin and brominated bisphenol A, which are also known and commonly used. Brominated bisphenol A type epoxy resin produced, phenol novolac or novolac type epoxy resin produced by glycidyl etherification of orthocresol novolak, tetraglycidyl metaxylenediamine, tetraglycidyl 1 obtained by reacting various amines with epichlorohydrin , 3-bisaminomethylcyclohexane, tetraglycidyl diaminodiphenylmethane, triglycidyl-p-aminophenol, triglycidyl-m Aminophenol, diglycidyl aniline, glycidyl amine compounds such as diglycidyl ortho-toluidine is used.

As the polyol used in the urethane acrylate resin, alkylene diols such as ethylene glycol, propylene glycol,
Diethylene glycol, diisopropylene glycol,
Polyethylene glycol, polypropylene glycol,
Polyoxymethylene, polyethylene oxide, polypropylene oxide, etc. as polyether polyols such as hydroxyalkyl ethers of butanediol, polyesters having hydroxyl groups at both ends produced by the above-mentioned organic polyols and polycarboxylic acids as polyester polyols. Polyol or the like is used.

As the polyisocyanate used for the urethane acrylate resin, tolylene diisocyanate, isophorone diisocyanate, polymethylene polyphenyl diisocyanate and the like are used.

The hydroxyalkyl (meth) acrylate used in the urethane acrylate resin is
Usually, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, etc. are used, and the hydroxyl group is usually bonded to the carbon at the beta position of the alkyl group. Alkyl groups can usually contain up to 8 carbon atoms.

The above-mentioned unsaturated carboxylic acids are compounds which have a carboxyl group and a reactive unsaturated bond, and anhydrides or metal salts thereof, which are easily hydrated or ion-exchanged with water molecules to form carboxyl groups. Atomic group (bond) that can be a base
Means an unsaturated compound having

As the compound having a carboxyl group and a reactive unsaturated bond, any conventionally known compound can be used. For example, acrylic acid, methacrylic acid, fumaric acid,
Examples thereof include maleic acid, itaconic acid, phthalic acid monohydroxyethyl acrylate, succinic acid monohydroxyethyl acrylate, phthalic acid monohydroxyethyl methacrylate, and succinic acid monohydroxyethyl methacrylate.

As the above-mentioned unsaturated carboxylic acid anhydride,
Any conventionally known one is used. Examples thereof include maleic anhydride and itaconic anhydride. Any conventionally known metal salt of the unsaturated carboxylic acid may be used. For example, specifically, lithium, sodium, potassium, magnesium, calcium, strontium, barium, manganese, iron, cobalt, nickel,
Examples thereof include (meth) acrylic acid salts, maleic acid salts, and itaconic acid salts of metals such as copper, silver, zinc, and aluminum.

The above-mentioned unsaturated sulfonic acids are sulfone which is easily hydrated or ion-exchanged with a water molecule or the like such as a compound having a SOOH group and a reactive unsaturated bond, and its anhydride and metal salt. Atomic group that can be an acid group (bond)
Means an unsaturated compound having

Any conventionally known compound can be used as the compound having the SOOH group and the reactive unsaturated bond. For example, parastyrene sulfonic acid, beta styrene sulfonic acid, allyl sulfonic acid, 2-acrylamido-
2-methyl propane sulfonic acid etc. are mentioned.

The metal salt of unsaturated sulfonic acid includes
Any conventionally known one is used. For example, potassium parastyrene sulfonate, sodium parastyrene sulfonate, sodium beta styrene sulfonate, sodium allyl sulfonate, and sodium 2-acrylamido-2-methylpropane sulfonate may be mentioned.

As the above-mentioned unsaturated sulfonic acid anhydride,
Any conventionally known one is used. For example, there is allyl sulfonic anhydride. The unsaturated phosphoric acids are P
A compound having an OOH group and a reactive unsaturated bond and an atomic group (bond) capable of becoming a POOH group such as a metal salt thereof, an anhydride metal salt thereof, etc., which can be easily hydrated or ion-exchanged with a water molecule etc. Means an unsaturated compound having.

The following compounds are used as the compound having the POOH group and the reactive unsaturated bond. For example, mono (2-acryloyloxyethyl) dihydrogen phosphate, mono (2-methacryloyloxyethyl) dihydrogen phosphate, di (2-acryloyloxyethyl) monohydrogen phosphate, di (2-methacryloyloxyethyl) mono Hydrogen phosphate, mono {5-carbonyloxy (2-acryloyloxyethyl) pentane} dihydrogen phosphate, mono {5-carbonyloxy (2-methacryloyloxyethyl) pentane} dihydrogen phosphate, di {5-carbonyloxy (2-Acryloyloxyethyl) pentane} monohydrogen phosphate, di {5-carbonyloxy (2-acryloyloxyciethyl) pentane} monohydrogen phosphate Doors and the like.

As the metal salt of unsaturated phosphoric acid, known and commonly used ones are used. For example, mono (2-acryloyloxyethyl) disodium phosphate, mono (2
-Methacryloyloxyethyl) dipotassium phosphate and the like.

As the unsaturated phosphoric acid anhydride, known and conventional ones are used. For example, mono (2-acryloyloxyethyl) dihydrogen phosphate anhydrous and the like can be mentioned.

The unsaturated isocyanate used in the invention described in claim 1 means a compound having an isocyanate group and a reactive unsaturated bond, and an alkali metal isocyanic acid salt and an alkenyl halide are reacted by a known method. Can be obtained. Specifically, there are allyl isocyanate, 1-butene-3-isocyanate, 2-methylpropene-3-isocyanate and the like. It can also be synthesized by an addition reaction between an unsaturated alcohol and polyisocyanate.

The unsaturated isothiocyanate used in the invention of claim 1 means a compound having an isothiocyanate group and a reactive unsaturated bond, and isothiocyanic acid alkali metal salt and alkenyl halide are prepared by a known method. Is obtained by reacting. Specific examples thereof include allyl isothiocyanate, 1-butene-3-isothiocyanate, and 2-methylpropene-3-isothiocyanate. It can also be synthesized by an addition reaction of an unsaturated alcohol and polyisothiocyanate.

The polyol used in the invention described in claim 1 means a compound having a plurality of hydroxyl groups in the molecule. Specific examples thereof include diols, triols, tetraols and mixtures thereof. It is mainly divided into an aliphatic polyol and an aromatic polyol, and among these, representative ones as the aliphatic polyol include ethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, triethylene glycol,
Neopentyl glycol, dibromoneopentyl glycol, hexamethylene glycol, trimethylene glycol, trimethylolpropane, glycerin, pentaerythritol diallyl ether, hydrogenated bisphenol A
and so on.

Typical aromatic polyols are bisphenol A or bisphenol S, or bisphenol A or bisphenol S thereof.
In addition, there are polyoxyalkylene bisphenol A and polyoxyalkylene bisphenol S obtained by adding an aliphatic oxirane compound such as ethylene oxide, propylene oxide or butylene oxide in the range of 1 to 20 on average in one molecule.

The polymercaptan used in the invention described in claim 1 means a compound having a plurality of mercapto groups in the molecule, and known and conventional ones are used. For example, 1,2
-Propanedithiol, 1,3-propanedithiol,
1,4-butanedithiol, 1,6-hexanedithiol, 1,10-decanedithiol, 2,3-mercapto-1-propanol, di (2-mercaptoethyl) ether, pentaerythritol tetra (mercaptoacetate), pentaerythritol Tetra (3-mercaptopropionate) and the like.

When at least one of unsaturated carboxylic acids, unsaturated sulfonic acids, unsaturated phosphoric acids, unsaturated isocyanates and unsaturated isothiocyanates is used in the molding material, the total amount thereof is
0.1 to 70% by weight is preferable, and more preferably 0.5 to 20% by weight, of the total resin content (total amount of thermosetting resin, copolymerizable monomer, and thermoplastic resin) of the molding material. .
If the amount used is less than 0.1% by weight, it is difficult to obtain the effect of sufficiently improving the adhesion to the coating layer, and conversely 70% by weight
If it exceeds, the viscosity of the composition will be too low, so SMC
Alternatively, it tends to be difficult to form the BMC (solid state).

When a polyol and / or polymercaptan is used as the molding material, the amount thereof is
As a total, the total resin content (thermosetting resin,
0.1) out of total amount of copolymerizable monomer and thermoplastic resin)
-20% by weight is preferable, and 1-12% by weight is more preferable. If the amount used is less than 0.1% by weight, it is difficult to obtain the effect of sufficiently improving the adhesion to the coating layer. On the other hand, if it exceeds 20% by weight, the viscosity of the composition becomes too low, resulting in SMC or It tends to be difficult to obtain a BMC form (solid state).

When a polyol and / or polymercaptan is used as the coating material, the amount of the resin and the total resin content (thermosetting resin, copolymerizable monomer,
The total amount of the thermoplastic resin) is preferably 0.1 to 20% by weight, more preferably 1 to 12% by weight. If the amount used is less than 0.1% by weight, it is difficult to obtain the effect of sufficiently improving the adhesion to the molding material, and if it exceeds 20% by weight, the water resistance of the coating layer tends to deteriorate. Have.

When at least one kind of unsaturated carboxylic acids, unsaturated sulfonic acids, unsaturated phosphoric acids, unsaturated isocyanates and unsaturated isothiocyanates is used for the coating material, the total amount thereof is 0.1 to 90% by weight of the total resin content of the coating material (total amount of thermosetting resin, copolymerizable monomer, thermoplastic resin)
Is preferred, and more preferably 0.5 to 30% by weight. If the amount used is less than 0.1% by weight, it is difficult to obtain the effect of sufficiently improving the adhesion to the molding material, and if it exceeds 90% by weight, the water resistance of the coating layer tends to deteriorate. Have.

In the molding material and the coating material used in the invention described in claim 1, polyvinyl acetate, polymethyl (meth) acrylate, polyethylene,
A thermoplastic resin such as ethylene vinyl acetate copolymer, vinyl acetate-styrene copolymer, polybutadiene, saturated polyesters, saturated polyethers, etc. can be used in an appropriate amount, if necessary.

An appropriate amount of inorganic filler can be added to the molding material and the coating material used in the invention described in claim 1 according to the purpose and application. Examples of usable inorganic fillers are as follows. That is, elemental minerals such as sulfur, graphite and diamond, sulfide minerals such as pyrite, halogenated minerals such as rock salt and potassium rock salt, carbonate minerals such as calcium carbonate, phosphate minerals such as cyanite, vanadium such as carnotite. Salt minerals, barite (barium sulfate), gypsum (calcium sulfate) and other sulfate minerals, borax and other borate minerals, perovskite and other titanate minerals, mica, talc (talc), and flake wax. Natural products such as stones, kaolin, quartz, silicate minerals such as feldspar, titanium oxide, metal (hydr) oxides such as corundum (aluminum oxide) aluminum hydroxide, glass products such as (hollow) glass spheres Artificial minerals or processing it,
Purified or processed products and mixtures thereof are used.

The amount of the filler used in the molding material is 0 to 300 with respect to 100 parts by weight of the resin component (total amount of thermosetting resin, thermoplastic resin and copolymerizable monomer).
It is preferably added in parts by weight. If the amount added exceeds 300 parts, it becomes difficult to uniformly disperse the filler in the resin and the monomer, and since the viscosity becomes too high, the flow in the mold deteriorates and dimensional stability is obtained. Becomes difficult.

The amount of the above filler used for the coating material is 0 to 150 relative to 100 parts by weight of the resin component (total amount of thermosetting resin, thermoplastic resin, copolymerizable monomer).
It is preferably added in parts by weight. If the addition amount exceeds 150 parts, the viscosity becomes too high, so that the fluidity in the mold becomes poor and it becomes difficult to spread the molding material over the entire target area.

Further, various reinforcing fibers, that is, glass fibers, carbon fibers and the like can be added to the molding material and the coating material as a reinforcing material in appropriate amounts, if necessary. Further, the above molding material and coating material, if necessary, styrene, alphamethylstyrene, divinylbenzene,
Copolymerizable monomers such as vinyltoluene, diallyl phthalate, various acrylate monomers, various methacrylate monomers, ketone peroxides, diacyl peroxides, hydroperoxides, dialkyl peroxides, alkyl peresters, percarbonates , Known initiators such as peroxyketals, dimethylaniline, known curing accelerators such as cobalt naphthenate, polymerization inhibitors such as parabenzoquinone, carbon black and titanium oxide, iron oxide, cyanine pigments, aluminum flakes, Pigments such as nickel powder, gold powder, silver powder, azo dyes, anthraquinone dyes, indigoid dyes, stilbene dyes, conductivity imparting agents such as carbon black, emulsifiers, metal soaps such as zinc stearate, and aliphatic phosphates. , Lecithin It may be added an appropriate amount in accordance with such a release agent application, the purpose.

The molding material used in the invention of claim 1 is the SM compounded by the conventionally known method using the compounding material as described above.
It becomes a molding material having the form of C or BMC. Specifically, for example, when at least one kind of unsaturated carboxylic acid, unsaturated sulfonic acid, unsaturated phosphoric acid, unsaturated isocyanate and unsaturated isothiocyanate is used for the molding material, styrene of unsaturated polyester resin is used. 0 to 30 parts by weight of a styrene solution of a thermoplastic resin such as polymethylmethacrylate, polystyrene and polyvinyl acetate (styrene concentration of 30 to 80% by weight) based on 50 to 99 parts by weight of a solution (styrene concentration of 40 to 70% by weight). , Unsaturated carboxylic acid, unsaturated sulfonic acid, or unsaturated phosphoric acid, unsaturated isocyanate and unsaturated isothiocyanate to 1 to 20 parts by weight of 100 parts by weight, and calcium carbonate, aluminum hydroxide, etc. 100-300 parts by weight of the filler powder of 0.1, a thickener such as magnesium oxide 0.1- 1 part to 200 parts by weight of reinforcing fibers such as glass fibers are impregnated with a kneading machine or an impregnating machine to obtain a solid form. The molding material is preferably used because it has excellent moldability, handleability, and physical properties of the molded product.

When a polyol and / or polymercaptan is used as the molding material, for example, a styrene solution of an unsaturated polyester resin (styrene concentration: 40 to 70) is used.
% By weight) 50 to 99 parts by weight, 0 to 30 parts by weight of a styrene solution of a thermoplastic resin such as polymethylmethacrylate, polystyrene, polyvinyl acetate (styrene concentration 30 to 80% by weight), polyol and / or polymercaptan 1 to 12 parts by weight are added to make 100 parts by weight, and filler powder 10 such as calcium carbonate and aluminum hydroxide is used.
0 to 300 parts by weight, thickener such as magnesium oxide 0.1
˜3 parts by weight, 0.1 to 5 parts by weight of an organic peroxide as an initiator are added and kneaded well, and reinforcing fibers such as glass fiber 1 to
A solid molding material obtained by impregnating 200 parts with a kneading machine or an impregnation machine is preferably used because it has excellent moldability, handleability, and physical properties of the molded product.

The coating material used in the invention described in claim 1 is kneaded into a liquid coating material by a conventionally known method using the compounding material as described above. In particular,
For example, when a polyol and / or polymercaptan is used as the coating material, a styrene solution of an unsaturated polyester resin, an epoxy acrylate resin or a urethane acrylate resin (styrene concentration: 40 to 70% by weight) 6
0 to 99 parts by weight of polymethylmethacrylate,
A styrene solution of a thermoplastic resin such as polystyrene or polyvinyl acetate (styrene concentration 30 to 80% by weight) 0 to 30
1 to 12 parts by weight of polyisocyanate, polyamine, or epoxy is added to 100 parts by weight, and filler powder 10 to 150 such as calcium carbonate or barium sulfate is added.
1 part by weight, 0.1 to 3 parts by weight of an internal release agent such as zinc stearate, and 0.1 to 5 parts by weight of an organic peroxide as an initiator are added and kneaded well. It is suitable for use because of its excellent physical properties.

Further, the coating material is an unsaturated carboxylic acid,
When unsaturated sulfonic acids, saturated phosphoric acids, unsaturated isocyanates and unsaturated isothiocyanates are used, a styrene solution of an unsaturated polyester resin, an epoxy acrylate resin or a urethane acrylate resin (styrene concentration 40 to 70% by weight) 60 to 99 0 to 30 parts by weight of a styrene solution of a thermoplastic resin such as polymethylmethacrylate, polystyrene, or polyvinyl acetate (styrene concentration 30 to 80% by weight), unsaturated carboxylic acids, unsaturated sulfonic acids, unsaturated 1 to 20 parts by weight of at least one kind of phosphoric acid, unsaturated isocyanate and unsaturated isothiocyanate is added to make 100 parts, and filler powder 10 to 15 such as calcium carbonate and barium sulfate.
0 parts by weight, internal release agent such as zinc stearate 0.1-3
A mixture of 1 part by weight and 0.1 to 5 parts by weight of an organic peroxide as an initiator and well kneaded is preferably used because it has excellent moldability, handleability, and physical properties of the molded product.

The invention described in claim 2 is characterized in that the molding material and the coating material of the invention described in claim 1 thus obtained are used, and the other steps are conventionally known. The in-mold coating molding method can be used.

For example, SMC is put in a molding die heated to 130 to 160 ° C. and pressure-molded at a pressure of 40 to 120 kg / cm ² for 30 seconds to 5 minutes, and then the mold is slightly opened to cover the coating material. Injection, then 5-120 kg / cm ² ,
There is a method in which the coating material is spread over the entire surface of the molded SMC and cured by reheating and repressurizing at 130 to 160 ° C. for 30 seconds to 5 minutes to form a coating.

Further, it is disclosed in Japanese Patent Publication No. 4-33252.
So that SMC at 130-160 ° C, 40-120k
g / cm²After pressure molding for several tens of seconds to several minutes, the pressure is adjusted to 10
~ 30 kg / cm²Use a high-pressure injection machine with the pressure reduced to
100-300 kg / cm ²High pressure of coating material in the mold
And inject again into 30 to 100 kg / cm²Increase pressure to cover
There is also a method of spreading and hardening the material,
The coating material and the molding material which are the features of the present invention are used in the coating method.
If a covering material is used, it is easy to improve the adhesion between the film and the molding material.
A good coating can be formed.

[0051]

In the thermosetting resin composition according to the first aspect of the present invention, one of the thermosetting resin compositions constituting the molding material and the coating material is provided with an unsaturated carboxylic acid, an unsaturated sulfonic acid or an unsaturated carboxylic acid. It contains at least one kind of phosphoric acid, unsaturated isocyanate and unsaturated isothiocyanate, and the other contains at least one kind of polyol and polymercaptan.

When at least one of unsaturated carboxylic acids, unsaturated sulfonic acids, unsaturated phosphoric acids, unsaturated isocyanates and unsaturated isothiocyanates is contained in the molding material, it is possible to remove these at the time of pressure molding. The compound is copolymerized with the thermosetting resin to give a carboxyl group, SOOH group, POOH group, isocyanate group or isothiocyanate group on the surface of the molding material. It reacts with the polyol contained in the coating material and appears on the surface at the time of molding, the OH group and mercapto group of polymercaptan as shown in the following chemical formula, and a strong cured resin layer (mutually) is formed at the interface between the molding material and the coating material. It is presumed that they are entangled with each other by invading the crosslinked structure of the other material), and therefore, the adhesion between the molding material and the coating layer can be improved.

[0053]

[Chemical 1]

[0054]

[Chemical 2]

In the above chemical formulas 1 and 2, R ¹ and R
^3: unsaturated carboxylic acid ^{residues, R 2, R 6, R} 10, R 14, R 18:
Polyol residue, R ⁴ , R ⁸ , R ¹² , R ¹⁶ : Polymercaptan residue, R ⁵ , R ⁷ : unsaturated sulfonic acid residue, R ⁹ , R ¹¹ :
Unsaturated phosphoric acid residue, R ¹³ , R ¹⁵ : unsaturated isocyanate residue, R ¹⁷ , R ¹⁹ : unsaturated isothiocyanate residue.

When a polyol or polymercaptan is used as the molding material, these produce OH groups or mercapto groups on the surface during pressure molding. This is an unsaturated carboxylic acid, unsaturated sulfonic acid, unsaturated phosphoric acid, unsaturated isocyanate and unsaturated isothiocyanate carboxyl group, SOOH group, POOH group, isocyanate group contained in the coating material and copolymerized at the time of molding.
It has a function of reacting with an isothiocyanate group to form a chemical bond as shown in the following chemical formula, and forming a cured resin layer such as IPN across the interface between the coating film and the molding material. The adhesion between the material and the coating can be improved.

[0057]

[Chemical 3]

[0058]

[Chemical 4]

In the chemical formulas of Chemical Formulas 3 to 4, R ²¹ ,
R ²⁵ , R ²⁹ , R ³³ , R ³⁷ : Polyol residue, R ²² , R ²⁴ : Unsaturated carboxylic acid residue, R ²³ , R ²⁷ , R ³¹ , R ³⁵ , R ³⁹ : Polymercaptan residue, R ²⁶ , R ²⁸ : unsaturated sulfonic acid residue, R ³⁰ , R ³² : unsaturated phosphoric acid residue, R ³⁴ , R ³⁶ : unsaturated isocyanate residue, R ³⁸ , R ⁴⁰ : unsaturated isothiocyanate residue is there.

[0060]

EXAMPLES The present invention will be clarified by giving Examples and Comparative Examples of the present invention. In the following, parts are parts by weight unless otherwise specified. In addition, the invention and the invention according to claim 1 and the comparative example will be described separately.

Examples and Comparative Examples of Invention of Claim 1 [Preparation of Material] 1. Unsaturated polyester resin liquid 5 mol of isophthalic acid, 5 mol of maleic acid and 10 mol of propylene glycol were condensed by a conventionally known method to obtain an unsaturated polyester resin (molecular weight: about 1000). This was dissolved in styrene monomer to obtain an unsaturated polyester resin liquid. (Styrene content about 40% by weight, UP, UP
Abbreviated. ) 2. Polystyrene-based low-shrinking agent resin liquid (polystyrene resin approximately 30% by weight, styrene monomer approximately 70% by weight,
Abbreviated as LPA. )

3. 4. Diethylene glycol (Wako Pure Chemical Industries, Ltd., hereinafter abbreviated as DEG) 4.1,4-Butanediol (Wako Pure Chemical Industries, Ltd., hereinafter abbreviated as BDO) Neopentyl glycol (manufactured by Wako Pure Chemical Industries, Ltd., hereinafter abbreviated as NPG) 6.1,2-propanedithiol (manufactured by Wako Pure Chemical Industries, Ltd.,
Hereinafter, abbreviated as PDT) 7.1,6-hexanedithiol (Wako Pure Chemical Industries, Ltd.,
Hereinafter referred to as HDT) 8. Methacrylic acid (manufactured by Wako Pure Chemical Industries, Ltd., hereinafter abbreviated as MAA) 9. Maleic anhydride (Wako Pure Chemical Industries, Ltd., hereinafter AMA
Abbreviated) 10. Allylsulfonic acid (manufactured by Wako Pure Chemical Industries, Ltd., hereinafter, A
(Abbreviated as SA) 11. Potassium parastyrene sulfonate (Wako Pure Chemical Industries, Ltd., abbreviated as SSA hereinafter) 12. Mono (2-acryloyloxyethyl) dihydrogen phosphate (manufactured by Wako Pure Chemical Industries, Ltd., AE
(Abbreviated as HP) 13. Allyl isocyanate (manufactured by Wako Pure Chemical Industries, Ltd., hereinafter abbreviated as AI)

14. Allyl isothiocyanate (manufactured by Wako Pure Chemical Industries, Ltd., hereinafter abbreviated as AIT) 15. 16. Calcium carbonate powder (NS-100: manufactured by Nitto Koka Kogyo Co., Ltd., hereinafter abbreviated as “calcium charcoal”) 16. Curing agent (Kayabutyl B: Kayaku Akzo Co., tertiary butyl peroxobenzoate content 98% by weight) 17. Thickener (magnesium oxide powder, Kyowamag 1)
50: Kyowa Chemical Industry Co., Ltd.) 18. Glass fiber (Roving made by Asahi Fiber Glass: ER4630LBD166W cut into a length of 25 mm, abbreviated as GF hereinafter)

[Manufacture of molding material] Of these materials,
Compounding materials other than glass fiber were mixed according to the following Tables 1 to 6 and sufficiently stirred, and then glass fiber was impregnated with an SMC impregnation device to obtain SMC.

[Production of Coating Material] The above-mentioned compounded materials were mixed according to the following Tables 1 to 6 and sufficiently kneaded to obtain a coating material.

[Molding] SMC obtained as described above
And the coating material were used and molded as follows.

The above S was placed in a die of a 30 cm × 30 cm square flat plate in which the upper die was heated to 150 ° C. and the lower die was heated to 150 ° C.
After charging about 700 g of MC (which corresponds to a thickness of about 4 mm) and press-molding at a pressure of 100 kg / cm ² for 100 seconds, the mold was slightly opened to make the coating material 1 above.
Inject 0 ml, close the mold again, and use 1 at 80 kg / cm ² .
Molded SM by reheating and repressurizing for 20 seconds
The coating material was spread over the entire surface of C and cured to form a coating. After that, the mold is opened and demolded, and the surface has a thickness of about 10
A molded article coated with a 0 μm coating was obtained.

[Evaluation] On the surface of the molded article thus obtained, using a cutter knife, draw a straight line reaching 11 substrates at 2 mm intervals, and further draw a 11 straight line orthogonal to it. An adhesive tape (Cellotape, manufactured by Sekisui Chemical Co., Ltd.) was attached to the eye-shaped portion and then peeled off, and the number of remaining squares of the squares on which the coating was not peeled off was examined (cross-grid adhesion test).

From the obtained molded product, 10 cm × 10
A test piece of cm is cut out, and in a program-type oven, 80 cycles of 80 ° C. × 5 hours → 23 ° C. × 1 hour → −30 ° C. × 5 hours → 23 ° C. × 1 hour → repeated cooling / heating cycle is 1 cycle, and 10 cycles are consecutive. I went over again. A cross-cut adhesion test was also performed on the test piece after the completion of the cold heat repetition test.

Tables 1 to 6 below show the results of the adhesion obtained in the above manner and after the repeated heat and cold test. (Examples 1 to 28) According to the following Tables 1 to 3, the molding material and the coating material were blended, and molding and evaluation were performed by the above-mentioned method. The results are shown in Tables 1 to 3 below. The adhesion of the coating was good both in the initial stage and after the cold and heat repeated test.

(Comparative Examples 1 to 24) According to the following Tables 4 to 6, the molding material and the coating material were blended, and molding and evaluation were carried out by the above-mentioned method. The results are also shown in Tables 4 to 6 below. The adhesion was good at the beginning,
It was poor after the cold heat repeated test.

(Comparative Example 25) A molding material and a coating material were blended according to Table 6 below, and molding and evaluation were carried out by the above-mentioned method. The results are also shown in Table 6 below. The adhesiveness was poor both in the initial stage and after the cold and heat repeated test.

[0073]

[Table 1]

[0074]

[Table 2]

[0075]

[Table 3]

[0076]

[Table 4]

[0077]

[Table 5]

[0078]

[Table 6]

The symbols used for the molding material and the coating material in Tables 1 to 6 have the following meanings. UP: Unsaturated polyester resin liquid LPA: Polystyrene-based low-shrinking agent resin liquid DEG: Diethylene glycol BDO: 1,4-butanediol NPG: Neopentyl glycol PDT: 1,2-propanedithiol HDT: 1,6-hexanedithiol

MAA: Methacrylic acid AMA: Maleic anhydride ASA: Allyl sulfonic acid SSA: Potassium parastyrene sulfonate AEHP: Mono (2-acryloyloxyethyl) dihydrogen phosphate AI: Allyl isocyanate AIT: Allyl isothiocyanate charcoal: Calcium carbonate powder GF: Glass fiber

[0081]

As described above, according to the first aspect of the present invention, the unsaturated carboxylic acid, the unsaturated sulfonic acid, the unsaturated phosphoric acid, the unsaturated isocyanate and the unsaturated isomeric compound are used as the molding material and the coating material. At least one of thiocyanates is blended, and at least one of these unsaturated carboxylic acids, unsaturated sulfonic acids, unsaturated phosphoric acids, unsaturated isocyanates and unsaturated isothiocyanates is copolymerizable during pressure molding. The double bond undergoes a copolymerization reaction with the thermosetting resin composition at the time of pressure molding to give a carboxyl group, a SOOH group, a POOH group, an isocyanate group, and an isothiocyanate group on the surface. Therefore, it reacts with the hydroxyl group and mercapto group of the polyol and polymercaptan contained in the other of the molding material and the coating material to form a chemical bond. As a result, it has the function of forming a strong thermosetting resin layer at the interface between the two, and by this chemical bond, the adhesion between the molding material and the coating layer can be improved, and in a harsh environment such as repeated heat and cold. It is possible to maintain sufficient adhesion even after the change.

When the thermosetting molding material and the coating material according to claim 1 are used, as in the invention described in claim 2, the coating layer has excellent adhesion to the molded article substrate, and is repeatedly subjected to cold heat. It is possible to provide a coated molded article in which a coating layer having sufficient adhesion is formed even after such a severe environmental change.

Claims (2)

[Claims] 1. A thermosetting resin composition for use in an in-mold coating molding method, which comprises coating a thermosetting coating material on a base material made of a thermosetting molding material in a mold to form a coating layer. One of the thermosetting molding material and the thermosetting coating material is a thermosetting resin and one of unsaturated carboxylic acids, unsaturated sulfonic acids, unsaturated phosphoric acids, unsaturated isocyanates and unsaturated isothiocyanates. A thermosetting resin composition containing at least one kind, and the other is a thermosetting resin composition containing a thermosetting resin and at least one kind of polyol and polymercaptan. And a thermosetting resin composition for in-mold coating molding. 2. A method of coating a coating material made of a thermosetting resin composition on a substrate made of the molding material in a mold when molding a molding material made of a thermosetting resin composition, An in-mold coating molding method, wherein the thermosetting molding material and the thermosetting coating material according to claim 1 are used as the thermosetting molding material and the thermosetting coating material, respectively.