JPH04363313A - Reactive resin fine particle, its production and resin composition for heat-forming - Google Patents

Abstract

PURPOSE:To obtain the subject particle having a shell part formed on the surface of a core particle and capable of giving a molded article having high transparency and durability by polymerizing a polyfunctional monomer and a non-aromatic monomer in the presence of a core particle composed of a three-dimensionally crosslinked resin having a specific crosslinking degree. CONSTITUTION:The objective reactive resin fine particle can be produced by polymerizing a monomer mixture composed of styrene, n-butyl acrylate and neopentyl glycol dimethacrylate, etc., to synthesize a core particle of a three- dimensionally crosslinked resin having a crosslinking degree of 0.05-2.0 mmol/g and polymerizing a polyfunctional monomer having at least one kind of 1- monosubstituted or 1,1-disubstituted radically polymerizable ethylenic unsaturated bond and at least one kind of 1,2-disubstituted, 1,1,2-trisubstituted or 1,1,2,2- tetrasubstituted radically polymerizable ethylenic unsaturated bond in the molecule and a non-aromatic radically polymerizable monomer, thereby forming a shell part having radically polymerizable ethylenic unsaturated bond on the surface of the core particle.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to novel three-dimensional resin fine particles having crosslinkable reactive groups on their surfaces and a method for producing the same.

The present invention also provides a thermosetting resin composition for thermoforming, which contains the above-mentioned reactive resin fine particles, and more specifically, a marble-like resin composition with a rich transparency for use in bathtubs, washstands, kitchen counters, etc. SMC (Sheet Molding Compound) used to manufacture molded products
and BMC (bulk molding compound),
or other premix materials.

0003

[Prior Art] Generally, SM used for pressure and heat molding
For C and BMC, thermoplastic resins such as polymethyl methacrylate, polystyrene, polyethylene, polyvinyl acetate, or copolymers of these are used to prevent loss of surface gloss and cracks during molding due to curing shrinkage of the resin. is added as a low-shrinkage agent in the form of granules or in a state dispersed or dissolved in a crosslinking monomer.

[0004] By adding this thermoplastic resin, the thermoplastic resin undergoes phase separation from the matrix due to rapid heat generation during curing of the thermoplastic resin, and fine pores are generated and microscopic particles are generated due to significant thermal expansion of the thermoplastic resin. Cracks occur, and these phenomena offset the curing shrinkage of the thermosetting resin, suppressing shrinkage of the molded product as a whole.

[0005]

[Problems to be Solved by the Invention] However, as described above, when a thermoplastic resin is used as a low-shrinkage agent to suppress shrinkage during curing, it inevitably causes phase separation of the thermoplastic resin and fine pore formation. This is a serious problem in that light scattering occurs at the interface between the thermoplastic resin, micropores, and microcracks and the matrix, resulting in loss of transparency, which is an important characteristic of this type of molded product. occurs. In addition, in molded products that are brought into contact with hot water or heated, such as bathtubs and washstands, the former peels off from the latter at the interface between the thermoplastic resin and the matrix, allowing water to enter the micropores, resulting in whitening of the molded product. There is a problem in that the durability of the molded product, such as heat resistance and water resistance, decreases as a result.

By the way, the following two types of three-dimensional resin fine particles obtained by polymerizing a polyfunctional monomer and a polymerizable monomer have been known: i) First, α, β
- Synthesizing crosslinked fine particles from a polyfunctional monomer having at least two ethylenically unsaturated groups and a polymerizable monomer having an α,β-ethylenically unsaturated group; Fine particles (Japanese Patent Application Laid-Open No. 2002-121002) are prepared by introducing active hydrogen onto the particle surface using a nanoparticle, and then reacting the active hydrogen with a monomer having an ethylenically unsaturated group at the end to introduce an ethylenically unsaturated group onto the particle surface. 62-84113), ii) A polyfunctional monomer having at least two ethylenically unsaturated groups having different copolymerizability, and vinyl polymerization that can undergo a polymerization reaction only with one unsaturated group of the polyfunctional monomer. fine particles obtained by emulsion polymerization with a cross-linking monomer and leaving at least one unsaturated group of the cross-linking monomer intact (JP-A-62-246
(See Publication No. 916).

However, the former type of fine particles is intended to be blended into a solvent-based coating composition to form a coating film with excellent physical properties such as hardness, abrasion resistance, tensile strength, and heat resistance. In addition, the latter microparticles are intended to have functional polymers or foreign substances fixed on their surfaces, and be incorporated into solvent-based paint compositions to provide paints with excellent coating workability and storage stability. Therefore, none of these fine particles have ever been used as a low shrinkage agent for SMC or BMC.

In view of the above-mentioned circumstances, it is an object of the present invention to provide novel three-dimensional resin fine particles that can be incorporated into resin compositions as a low-shrinkage agent, as well as to provide a molded material that is highly transparent and has excellent durability. The object of the present invention is to provide a thermosetting resin composition for thermoforming, from which a product can be obtained.

[0009]

[Means for Solving the Problems] The present invention was completed by creating new three-dimensional resin fine particles having a crosslinkable reactive group on the particle surface, and the resin composition according to the present invention , was provided based on the knowledge that the above-mentioned problems can be solved by blending the above-mentioned fine particles into a resin composition as a low-shrinkage agent.

[0010] Throughout this specification, all percentages and parts are based on weight.

i) Reactive resin fine particles The reactive resin fine particles according to the present invention have a degree of crosslinking of 0.05.
It is composed of a core particle made of a three-dimensional crosslinked resin in the range of ~2.0 mmol/g, and a shell part formed on the surface of the particle and having a radically polymerizable ethylenically unsaturated bond, and the shell part is , 1-monosubstitution and 1,
1-di-substituted radically polymerizable ethylenically unsaturated bond (a
) and 1,2-di-substituted, 1,1
, 2-tri-substituted and 1,1,2,2-tetra-substituted radically polymerizable ethylenically unsaturated bonds (b). It is obtained by polymerizing the mixture and a non-aromatic radically polymerizable monomer (B) alone or in a mixture.

In the reactive resin fine particles according to the present invention, the 1-mono-substituted or 1,1-disubstituted radically polymerizable ethylenically unsaturated bond (a) in the polyfunctional monomer (A) for forming the shell portion is singly It is an ethylenically unsaturated bond that can be polymerized. 1,2-di-substituted, 1,1,2-
The tri-substituted or 1,1,2,2-tetra-substituted radically polymerizable ethylenically unsaturated bond (b) is an ethylenically unsaturated bond that is neither substantially homopolymerized nor copolymerized with the ethylenically unsaturated bond (a). It is a saturated bond. In addition, the non-aromatic radically polymerizable monomer (B) can copolymerize with the ethylenically unsaturated bond (a), but the ethylenically unsaturated bond (b)
) is a polymerizable monomer having one ethylenically unsaturated bond that does not substantially copolymerize.

[0013] Therefore, in other words, the reactive resin fine particles according to the present invention have a core particle made of a three-dimensionally crosslinked resin having a degree of crosslinking in the range of 0.05 to 2.0 mmol/g, and a and a shell part that is formed and has a radically polymerizable ethylenically unsaturated bond, and the shell part has a homopolymerizable ethylenically unsaturated bond (
a) and an ethylenically unsaturated bond (a) which does not substantially homopolymerize or copolymerize with the ethylenically unsaturated bond (a).
b) A single or a mixture of polyfunctional monomers (A) each having at least one of these, which can be copolymerized with the ethylenically unsaturated bond (a) but substantially copolymerized with the ethylenically unsaturated bond (b). It is obtained by polymerizing a single or a mixture of polymerizable monomers (B) having one ethylenically unsaturated bond that does not polymerize.

[0014] The weight ratio of the core particle to the shell part of the reactive resin fine particles is preferably core particle/shell part = 10/9.
It is in the range of 0 to 99/1. If this weight ratio (core particle/shell part, abbreviated as "C/S") is less than 10/90, the durability of the molded product will decrease, while if it exceeds 99/1, the composition or dispersion will The particle dispersibility of the particles decreases. A particularly preferred weight ratio is in the range 40/60 to 80/20.

[0015] The preferred average particle size of the reactive resin fine particles is 0.
．． It is in the range of 01 to 5 μm. If the particle size is less than 0.01 μm, the dimensional stability of the molded product will be poor, while if it exceeds 5 μm, the transparency and other appearance of the molded product will be deteriorated. A particularly preferred average particle size is in the range of 0.05 to 2 μm.

The refractive index of the shell portion is preferably adjusted so that the difference between the refractive index of the resin containing the reactive resin fine particles and the other compounds is within 0.05.

ii) Method for producing reactive resin particles The method for producing reactive resin particles according to the present invention has a crosslinking degree of 0.0.
A first step of synthesizing a core particle made of a three-dimensional crosslinked resin in the range of 5 to 2.0 mmol/g, and a radically polymerizable ethylenically unsaturated 1-mono- or 1,1-di-substituted compound in the molecule. At least one of the bonds (a) and 1,2
-di-substitution, 1,1,2-tri-substitution and 1,1,2,2
- Tetra-substituted radically polymerizable ethylenically unsaturated bond (
b) A single or a mixture of polyfunctional monomers (A) each having at least one of the following, and a single or a mixture of a non-aromatic radically polymerizable monomer (B) are polymerized to form core particles. a second step of forming a shell portion having a radically polymerizable ethylenically unsaturated bond on the surface thereof.

ii-a) First step The synthesis of core particles made of three-dimensionally crosslinked resin is carried out by, for example,
A crosslinkable monomer having at least two copolymerizable ethylenically unsaturated bonds is added to the vinyl polymerizable monomer, and the degree of crosslinking is 0.
．． 05-2.0 mmol/g, preferably 0.2-1.
This is carried out by emulsion polymerization using an amount of 0 mmol/g. The vinyl polymerizable monomer used here is not particularly limited, and the following are exemplified. (Meth)acrylate; for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, 2-ethylhexyl acrylate, lauryl methacrylate, phenyl acrylate, and the like. Polymerizable aromatic compounds; e.g. styrene, α
- Methylstyrene, vinyl ketone, t-butylstyrene, parachlorostyrene, vinylnaphthalene, etc. Carboxyl group-containing monomers; for example, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, etc. Hydroxyl group-containing monomers; for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, allyl alcohol, methallyl alcohol, etc. Nitrogen-containing alkyl (meth)acrylate; for example, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropyl acrylate, dimethylaminopropyl methacrylate, dimethylaminopropyl methacrylamide, etc. Polymerizable amides; for example, acrylamide, methacrylic amide, N-methylolacrylamide, N-methoxymethylacrylamide, etc. Polymerizable nitrile; for example, acrylonitrile, methacrylonitrile, etc. Vinyl halides; for example, vinyl chloride, vinyl bromide, vinyl fluoride. α-olefin; for example, ethylene, propylene, etc. Vinyl compounds; for example, vinyl acetate, vinyl propionate, etc. Diene compounds; for example, butadiene, isoprene, etc.

The crosslinking monomer is not particularly limited as long as it has two or more radically polymerizable ethylenically unsaturated bonds in its molecule, and the following are exemplified. Polymerizable unsaturated monocarboxylic acid ester of polyhydric alcohol;
For example, ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate,
1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, pentaerythritol diacrylate, pentaerythritol dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, glycerol diacrylate Acrylate, glycerol dimethacrylate, glycerol acroxy dimethacrylate, 1,1,1-trishydroxymethylethane diacrylate, 1,1,1-trishydroxymethylethane dimethacrylate, 1,1,1-trishydroxymethylethane triacrylate , 1,1,1-trishydroxymethylethane trimethacrylate, 1,
1,1-trishydroxymethylpropane diacrylate, 1,1,1-trishydroxymethylpropane dimethacrylate. Polymerizable unsaturated alcohol esters of polybasic acids; for example diallyl terephthalate, diallyl phthalate, triallyl trimellitate. Aromatic compounds substituted with two or more vinyl groups; for example divinylbenzene. Addition compound of a monomer having an epoxy group-containing ethylenically unsaturated bond and a monomer having a carboxyl group-containing ethylenically unsaturated bond; for example, a reaction product of glycidyl acrylate or glycidyl methacrylate and acrylic acid or methacrylic acid.

When an emulsifier is used, the amount used is 0.1 to 20 parts, preferably 2 to 10 parts, based on 100 parts of the total amount of the above monomers. The type of emulsifier is not particularly limited and may include anionic, cationic, amphoteric,
A nonionic surfactant, a reactive surfactant, a non-reactive surfactant, or the like may be used as appropriate. Examples of surfactants include the following. Anionic surfactants; for example, fatty acid soaps, higher alcohol sulfates, alkylbenzene sulfonates, dioctyl sulfosuccinates, commercially available reactive anionic emulsifiers such as "Latemul S-120A" and "Latemul S-180" manufactured by Kao Corporation. ”, “Latemul S-180A”: “New Frontier A229E” manufactured by Daiichi Kogyo Seiyaku Co., Ltd., “Aqualon HS-10”: “Eleminol JS-2”, “Eleminol S” manufactured by Sanyo Chemical Co., Ltd.
SS”: “RA-1022” manufactured by Nippon Nyukazai Co., Ltd., “RA
-1024”, “RA-421”, “RA-423”,
“Antox-MS-2N (7)”: Asahi Denka “S”
X-1154” “SX-1159” “SX-1163”
. Nonionic surfactants; for example, polyethylene glycol alkyl ether, polyethylene glycol alkyl phenyl ether, polyethylene glycol fatty acid ester, polypropylene glycol, polyethylene glycol ether, polyoxyethylene sorbitan fatty acid ester, as a commercially available reactive nonionic emulsifier, manufactured by Daiichi Kogyo Seiyaku. “New Frontier N177E” and “Aqualon RN-20” manufactured by Nippon Nyukazai Co., Ltd.: “RMA-8” manufactured by Nippon Nyukazai Co., Ltd.
62”, “RA-951”, “RA-953”, “RA
-954”, “RA-955”, “RA-957”, “
RA-958”: “SX-1151” manufactured by Asahi Denka Co., Ltd.
SX-1152”, “SX-1156”, “SX-11”
57". Commercially available reactive cationic emulsifiers include "Latemul K-180" manufactured by Kao Corporation and "RF" manufactured by Nippon Nyukazai Co., Ltd.
-755”, “RF-756”.

Particularly preferred emulsifiers are reactive emulsifiers and polyester emulsifiers having amphoteric ionic groups (Japanese Patent Application Laid-Open No. 1983-1999).
151727 and Japanese Unexamined Patent Publication No. 56-34725).

The method for preparing the core particles is not limited to the above-mentioned method, but conventional methods such as suspension polymerization, dispersion polymerization, and post-emulsification methods can be used, and crosslinking methods include radical polymerization and addition reaction. or condensation reaction, examples of functional group combinations for this reaction include carboxylic acid/amino group/epoxy group, hydroxyl/amino group/isocyanate, carboxylic acid/hydroxyl group/melamine, amino group/active ester group, etc. .

[0023] The core particles also contain the above-mentioned polyfunctional monomer (A
), the above radically polymerizable monomer (B), and a polyfunctional monomer (C ) can also be formed by emulsion polymerization of a mixture of

The polymerization reaction in the first step is carried out in the presence of a radical polymerization initiator, if necessary. The type of initiator is not particularly limited, and the following general initiators are used. Oil peroxides; for example benzoyl peroxide, parachlorobenzoyl peroxide, lauroyl peroxide, t-butyl perbenzoate. Aqueous peroxides; eg potassium persulfate, ammonium persulfate. Oily azo compounds; for example, azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile). Aqueous azo compounds; for example, anionic azobiscyanovaleric acid, cationic -2,2'-azobis(2-amidinopropane) hydrochloride.

ii-b) Second step Formation of the shell portion in the second step involves adding the polyfunctional monomer (A) alone or a mixture thereof and the radically polymerizable monomer (B) alone to the aqueous dispersion of the core particles. This is carried out by dropping a monomer group or a mixture of monomers and an initiator solution. As mentioned above, the polyfunctional monomer (A) contains at least one kind selected from the group consisting of 1-monosubstituted and 1,1-disubstituted radically polymerizable ethylenically unsaturated bonds (a) and 1 ,2-di-substituted,1,
At least one type selected from the group consisting of 1,2-tri-substituted and 1,1,2,2-tetra-substituted radically polymerizable ethylenically unsaturated bonds (b). Suitable polyfunctional monomers (A) include:
For example, those having an acrylic or methacrylic ethylenically unsaturated bond (a) and a maleic acid or fumaric acid type ethylenically unsaturated bond (b) are used.

Particularly suitable polyfunctional monomers (A) include, for example, the reaction product of maleic anhydride and 2-hydroxyethyl methacrylate, the reaction product of monobutyl maleate and glycidyl methacrylate, and the like.

[0027] As the non-aromatic radically polymerizable monomer (B), those exemplified as the vinyl polymerizable monomer used in the first step can be used, particularly methyl acrylate, methyl methacrylate, ethyl acrylate, (Meth)acrylic monomers such as ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, 2-ethylhexyl acrylate, lauryl methacrylate, and phenyl acrylate are preferably used.

In the reaction of the second step, the proportion of the polyfunctional monomer (A) in all the shell-forming monomers is preferably in the range of 1 to 50%. If the proportion of monomer (A) is less than 1%, the interface between the fine particles and the resin cannot be made sufficiently strong, resulting in poor durability of the molded product, and conversely, if it exceeds 50%, the dimensional stability of the molded product decreases. . A particularly preferred proportion of polyfunctional monomer (A) is in the range from 5 to 40%.

An emulsifier is also used in the second step polymerization reaction, if necessary. The amount and type of emulsifier used are as exemplified in the explanation of the first step.

The polymerization reaction in the second step is also usually carried out in the presence of a radical polymerization initiator. The type of initiator is not particularly limited, and those exemplified in the description of the first step are used as appropriate.

The reactive resin fine particles according to the present invention contain a monomer having at least one ethylenically unsaturated bond copolymerizable with the radically polymerizable ethylenically unsaturated bond (b) or a monomer group containing at least one kind thereof. 1
It is also possible to form a dispersion by dispersing up to 40 parts.

iii) Thermosetting resin composition for thermoforming The above-mentioned reactive resin fine particles are blended into a thermosetting resin as a low shrinkage agent and used to form a thermosetting resin composition for thermoforming. It will be done.

The thermosetting resin composition for thermoforming according to the present invention contains a thermosetting resin, an inorganic filler, and the above-mentioned reactive resin fine particles.

[0034] Examples of the thermosetting resin, which is one of the constituent components of the resin composition, include unsaturated polyester resins, thermosetting acrylic resins, and vinyl ester resins.

[0035] Examples of inorganic fillers, which are other constituents, preferably have a refractive index in the range of 1.46 to 1.60 and a diameter of 1 to 300 μm, more preferably 20 to 10 μm.
Examples include glass powder having an average particle size in the range of 0 μm, aluminum hydroxide (its refractive index is 1.57), silica lime, etc., which may be used alone or in a mixture. Furthermore, as an inorganic filler, one that has been surface-treated with a silane coupling agent is preferably used to give the molded product a transparent marble-like appearance and to improve the hot water resistance of the molded product. Ru. Particularly preferred inorganic fillers are glass powder, aluminum hydroxide and mixtures thereof having a refractive index in the above range. The reactive resin fine particles, which is another component of the resin composition, function as a low-shrinkage agent, and the average particle size thereof is preferably 0.01 to 5 μm, more preferably 0.02 μm.
~1 μm, and its refractive index is preferably 1
．． It is in the range of 46 to 1.60.

Regarding the refractive index of the inorganic filler and the reactive resin fine particles, in order to obtain a transparent molded article from a resin composition containing a combination of the thermosetting resin, the inorganic filler and the reactive resin fine particles, these three The refractive indexes of the resin and the filler are matched as much as possible to prevent light scattering at the interface between the resin and the filler and the interface between the resin and the reactive resin particles. Since the refractive index of a thermosetting resin is generally in the range of 1.48 to 1.57, the inorganic filler and reactive resin fine particles should have a refractive index of 1.46 to 1.60, which is close to the refractive index of the thermosetting resin. A material having a refractive index is preferable. Whether the refractive index is less than 1.46 or more than 1.60, light scattering becomes significant at the interface between the resin and the filler and the interface between the resin and the reactive resin particles, reducing the transparency of the molded product. . A particularly preferred refractive index of the inorganic filler and the reactive resin fine particles is the refractive index of the cured resin ±0.05.

Next, each constituent component and molding method of the resin composition according to the present invention will be explained in more detail.

A) Thermosetting resin The unsaturated polyester resin, which is one of the thermosetting resins, is
An unsaturated polyester prepolymer dissolved in an ethylenically unsaturated monomer, usually in the form of a syrup. Any known unsaturated polyester resin can be used as the unsaturated polyester resin. The unsaturated polyester prepolymer is derived by polycondensation of at least one type of polyhydric carboxylic acid including ethylenically unsaturated polycarboxylic acid and at least one type of diol. Examples of ethylenically unsaturated polycarboxylic acids include maleic acid, maleic anhydride, fumaric acid, itaconic acid, tetrahydrophthalic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, etc., and used in combination with these. Examples of polyhydric carboxylic acids include phthalic anhydride, isophthalic acid, terephthalic acid, tetrachlorophthalic anhydride,
Examples include adipic acid, sebacic acid, and succinic acid. Suitable examples of diol components include ethylene glycol, diethylene glycol, triethylene glycol,
, 2-propylene glycol, butanediol, neopentyl glycol, hydrogenated bisphenol A, 2,2-
Bis(4-oxyethoxyphenyl)propane, 2,2
-bis(4-oxypropoxyphenyl)propane and the like.

It is also possible to use prepolymers of unsaturated esters derived from polycarboxylic acids and ethylenically unsaturated alcohols, such as diallylphthalate (DAP).

As the ethylenically unsaturated monomer, one type or a combination of two or more types of radically polymerizable liquid monomers is used. Of course, the combination of monomers and polyester prepolymers used must be capable of forming a homogeneous solution. Suitable examples of monomers include vinyl aromatics such as styrene, vinyltoluene, α-methylstyrene, divinylbenzene; ethylenically unsaturated ester monomers such as ethyl acrylate, methyl methacrylate, diallylphthalate, triallylcyanuric acid, etc. However, of course, the monomers are not limited to those exemplified.

[0041] The ratio of the unsaturated polyester prepolymer and the ethylenically unsaturated monomer is generally 70:30 to 45:5.
It is preferable to use the combination in a weight ratio of 5:5, preferably 65:35 to 55:45. It is generally desirable that the monomer solution of the prepolymer has a viscosity of 50 to 8000 cP (at 25°C).

Thermosetting acrylic resins, which are other thermosetting resins, are produced by copolymerizing acrylic esters or methacrylic esters with other monomers to form carboxy groups, epoxy groups, hydroxy groups, amide groups, amino groups, etc. , which has an ethylenic double bond such as a vinyl group introduced therein, and is self-hardened by a catalyst and also hardened by a crosslinking agent. Any known thermosetting acrylic resin can be used as the thermosetting acrylic resin.

Vinyl ester resin, which is another example of thermosetting resin, is a resin having a vinyl group at the end of an ester main chain or an ether main chain, and is usually composed of an epoxy resin having a bisphenol A skeleton, Epoxy acrylate produced by reaction with an unsaturated monobasic acid such as acrylic acid or methacrylic acid is diluted with a polymerizable monomer such as styrene.

B) Inorganic Filler Glass powder, which is one of the inorganic fillers, has a refractive index of 1.46 because of its transparent marble-like appearance.
~1.60, preferably within the range of the refractive index of the cured resin ±0.05, and the average particle size is 1 to 300μ
It is desirable that the value be within the range of m. Regarding the glass composition, one having a composition of borosilicate glass is preferable, and glass having the following composition is particularly preferable.

[0045] SiO2; 40-65%, B2 O3
; 2-30%, alkali metal oxide; 2-25%, alkaline earth metal; oxide or ZnO; 5-30%, Al
2 O3; 0-25%, TiO2; 0-10%, Z
rO2; 0-10%.

[0046] Aluminum hydroxide, which is another example of an inorganic filler, has a particle size of 1 to 1 to
It is desirable that the diameter is in the range of 300 μm, and commercially available products such as Showa Denko's Hygilite H-310 and H-32 are preferable.
0 etc. are used. Aluminum hydroxide is a substance that also serves as a flame retardant.

[0047] The inorganic filler surface-treated with a silane coupling agent is one in which the above-mentioned inorganic powder such as glass powder or aluminum hydroxide is surface-treated with any known silane coupling agent. It is. As the silane coupling agent, silanes having an ethylenically unsaturated double bond and a hydrolyzable group in the molecule are preferably used, and suitable examples thereof include vinyltriethoxysilane, vinyltris-β -methoxyethoxysilane, γ-methacryloxypropyltrimethoxysilane, and the like. The amount of these silane coupling agents used is usually in the range of 0.01 to 2 parts by weight per 100 parts by weight of inorganic powder such as glass powder or aluminum hydroxide.

C) Reactive resin fine particles The reactive resin fine particles constituting the resin composition have a degree of crosslinking and an average particle size within the above-mentioned ranges. Further, the refractive index of the shell portion is adjusted so that the difference between the refractive index of the resin in which the reactive resin fine particles are blended and the refractive index of other compounds is within 0.05. A preferred refractive index is in the range of 1.46 to 1.60.

D) Compounding composition The resin composition according to the present invention preferably contains 100 to 400 parts of an inorganic filler and 5 parts or more of reactive resin fine particles, usually up to 30 parts, per 100 parts of a thermosetting resin. .

If the amount of inorganic filler is less than 100 parts per 100 parts of thermosetting resin, the weight and texture of the molded product will be poor, a transparent marble-like texture will not be obtained, and cracks will occur during molding. molded products with excellent heat resistance cannot be obtained. On the other hand, if the amount of inorganic filler exceeds 400 parts, fluidity necessary for molding cannot be obtained, machinability also deteriorates, and both moldability and mechanical properties of the molded product deteriorate.

If the amount of the reactive resin fine particles is less than 5 parts per 100 parts of the thermosetting resin, the shrinkage reduction effect of the reactive resin fine particles will not be sufficiently exerted, and cracks will easily occur. The reactive resin fine particles may be blended in an amount that provides the desired shrinkage reduction effect. There is no particular problem even if the amount exceeds 30 parts, but from an economical standpoint, 30 parts or less is appropriate. A particularly preferred blending ratio is 150 to 350 parts of the inorganic filler to 100 parts of the thermosetting resin.
parts, and 10 to 20 parts of reactive resin fine particles.

E) Other ingredients In the resin composition according to the present invention, in addition to the above-mentioned essential ingredients, other ingredients conventionally used in thermosetting resin compositions of this type as required may be optionally added. Can be added. Such compounding agents include fiber reinforcing agents, colorants, internal mold release agents, thickeners, water-containing water retention agents, and the like. As a fiber reinforcing agent, the fiber length is 0.5 to 50 mm.
Glass fibers, aramid fibers, vinylon fibers, polyester fibers, polyimide fibers, etc. are used. As the colorant, organic or inorganic pigments and toners using the pigments are used. As the internal mold release agent, metal soaps such as zinc stearate and calcium stearate, and those based on phosphate esters are generally used. As the thickener, alkaline earth metal oxides or hydroxides such as magnesium oxide and calcium hydroxide are preferred.

[0053] Curing catalysts important for completing the curing of thermosetting resins include benzoyl peroxide, parachlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide,
Acetyl peroxide, dicumyl peroxide, 2
,5-dimethyl-2,5-di(t-butylperoxy)
Organic peroxides such as hexane, t-butyl perbenzoate are used alone or in combination. The amount of the curing catalyst used may be a so-called catalytic amount, and is preferably in the range of 0.3 to 2.5% by weight based on the resin.

F) Molding method The resin composition according to the present invention can be shaped into a sheet, a rice cake, a column,
It is thickened into pellet form, etc., and SMC and BMC
It is used as a material for manufacturing various molded products such as bathtubs, kitchen counters, washstands, bathroom panels, table tops, and other highly transparent molded products. The method of thermoforming the resin composition includes a pressure and heat molding method. Molding conditions are not particularly limited, but are generally 9.
It is preferable to carry out the process at a temperature of 0 to 160 DEG C. and a pressure of 20 to 140 kg/cm@2 gauge.

[0055]

[Function] The reactive resin fine particles according to the present invention have the ethylenically unsaturated bond (b) remaining in the shell portion without being copolymerized, so the ethylenically unsaturated bond (b)
When blending the fine particles with a monomer or thermosetting resin having at least one ethylenically unsaturated group that can be copolymerized with the monomer dispersion or thermosetting resin composition and performing a curing reaction, The above ethylenically unsaturated bond (
b) is copolymerized with the above monomer or the ethylenically unsaturated group of the thermosetting resin, the reactive resin fine particles are chemically bonded to the matrix, and the fine particles function as a low-shrinkage agent. Therefore, the phenomenon that light is scattered at the interface between the reactive resin fine particles and the matrix and the transparency is impaired does not occur at all.

Further, the chemical bonding between the reactive resin fine particles and the matrix as described above greatly improves the durability such as heat resistance and water resistance of the obtained molded article.

[0057] Thus, by using the above-mentioned reactive resin fine particles, curing shrinkage of the resin can be reliably suppressed, and a molded article that is highly transparent and has excellent durability and dimensional stability can be obtained.

[0058]

[Example] Next, (a) production of reactive resin fine particles, (
The present invention will be explained in more detail by giving specific examples of b) production of a thermosetting resin molded product and (c) quality test of the molded product.

(a) Reactive resin fine particle production example 1 (Ampholytic polyester emulsifier) 134 parts of bishydroxyethyl taurine was placed in a glass reactor equipped with a thermometer, reflux condenser, nitrogen gas inlet tube, stirrer and decanter. , 130 parts of neopentyl glycol, 236 parts of azelaic acid, 186 parts of phthalic anhydride, and 27 parts of xylene were respectively charged, and the reaction solution was heated to reflux. Water produced by the reaction was removed by azeotropy with xylene. It takes about 2 hours from the start of reflux to raise the temperature to 19.
The temperature was raised to 0°C, and stirring and dehydration were continued until the acid value equivalent to carboxylic acid reached 145.

Next, the temperature was cooled to 140° C. and maintained at this temperature, and 314 parts of versatile acid glycidyl ester “Cardura E10” (manufactured by Shell) was added dropwise over 30 minutes, and stirring was continued for 2 hours. The reaction has ended.

Thus, the acid value is 59 and the hydroxyl value is 90.
A polyester emulsifier having an amphoteric ionic group and made of a polyester resin having an average molecular weight of 1054 was obtained.

Production example 2 (polyfunctional monomer) thermometer,
A glass reactor equipped with a reflux condenser, an air inlet tube and a stirrer was charged with 98 parts of maleic anhydride, 130 parts of 2-hydroxyethyl methacrylate, 57 parts of toluene and p
- 0.5 part of methoxyphenol was added, the temperature of the mixed solution was raised to 110°C, and the reaction was carried out for 1 hour under air bubbling. The reaction solution was then cooled and the solvent was removed under reduced pressure.

In this way, a polyfunctional monomer (A) having two radically polymerizable ethylenically unsaturated bonds having different reactivities, a maleic acid-based ethylenically unsaturated bond and a methacrylic acid-based ethylenically unsaturated bond, was obtained.

Production Example 3 (Polyfunctional monomer) Thermometer,
172 parts of monobutyl malate, 149 parts of glycidyl methacrylate, and 0.5 parts of p-methoxyphenol were charged into a glass reactor equipped with a reflux condenser, an air inlet tube, and a stirrer, and the mixture was heated to 160°C. After heating and reacting for 1 hour under air bubbling, the reaction solution was cooled.

In this way, a polyfunctional monomer (A) having two radically polymerizable ethylenically unsaturated bonds having different reactivities, a maleic acid-based ethylenically unsaturated bond and a methacrylic acid-based ethylenically unsaturated bond, was obtained.

Example 1 (Fine particles obtained by two-step emulsion polymerization) 213 parts of deionized water and the reactive emulsifier "New Frontier A229E" were placed in a glass reactor equipped with a thermometer, a reflux condenser, a nitrogen gas inlet tube, and a stirrer. (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) were added in an amount of 5.5 parts, and the temperature of the mixed solution was raised to 81 to 85° C. while passing nitrogen gas through the mixture. Then, a monomer mixture consisting of 30 parts of styrene, 10 parts of n-butyl acrylate, and 10 parts of neopentyl glycol dimethacrylate, 20 parts of deionized water, 1 part of azobiscyanovaleric acid, and 0.64 part of dimethylethanolamine was prepared. Half of the aqueous initiator solution was added dropwise from separate dropping ports over 30 minutes. In this way, crosslinked core particles were obtained in the first step.

Next, a monomer mixture consisting of 15 parts of the polyfunctional monomer (A) obtained in Production Example 2, 17.5 parts of methyl methacrylate, and 17.5 parts of n-butyl acrylate, and the remainder of the above-mentioned aqueous initiator solution were added. Half of the solution was added dropwise over 30 minutes from separate dropping ports, and the reaction solution was aged for 1 hour and then cooled.

[0068] In this way, reactive resin fine particles (1) having an ethylenically unsaturated bond in the shell portion, an average particle size of 0.07 μm, and a C/S ratio of 5/5 were obtained.

Example 2 (Fine particles produced by two-step emulsion polymerization) A glass reactor equipped with a thermometer, a reflux condenser, a nitrogen gas inlet tube, and a stirrer was charged with 215 parts of deionized water and the particles obtained in Production Example 1. 10 parts of an emulsifier and 1 part of dimethylethanolamine were each added, and the temperature of the mixed solution was raised to 81 to 85°C while nitrogen gas was passed through. Next, a monomer mixture consisting of 35 parts of methyl methacrylate, 15 parts of n-butyl acrylate, 15 parts of ethylene glycol dimethacrylate, and 5 parts of the polyfunctional monomer (A) obtained in Production Example 2, 20 parts of deionized water, and Azobis 1 part cyanovaleric acid and 0.6 parts dimethylethanolamine
Seventy percent of the initiator aqueous solution consisting of 4 parts was dripped over 40 minutes from separate dropping ports. In this way, crosslinked core particles were obtained in the first step.

Next, the monomer mixture consisting of 10 parts of the polyfunctional monomer (A) obtained in Production Example 2, 15 parts of methyl methacrylate, and 5 parts of benzyl methacrylate and the remaining 30% of the aqueous initiator solution were each separated. The solution was added dropwise from the dropping port over a period of 20 minutes, and the reaction solution was aged for 1 hour and then cooled.

[0071] In this way, reactive resin fine particles (2) having an ethylenically unsaturated bond in the shell portion, an average particle size of 0.11 μm, and a C/S ratio of 7/3 were obtained.

Example 3 (Soap-free cationic large-sized particles) 109 parts of deionized water was charged into a glass reactor equipped with a thermometer, a reflux condenser, a nitrogen gas inlet pipe, and a stirrer, and the mixed solution was heated to 75 parts. The temperature was raised to ℃. Then, an aqueous solution consisting of 5 parts of methyl methacrylate, 0.5 parts of initiator 2,2'-azobis(2-amidinopropane) hydrochloride "V-50" (manufactured by Wako Pure Chemical Industries, Ltd.) and 10 parts of deionized water was added, After 10 minutes of reaction, methyl methacrylate 40
A monomer mixture consisting of 20 parts of n-butyl acrylate and 20 parts of 1.6 hexanediol dimethacrylate was added dropwise over 50 minutes.

After aging for 20 minutes, a monomer mixture consisting of 10 parts of the polyfunctional monomer (A) obtained in Production Example 3 and 10 parts of methyl methacrylate was added dropwise over 10 minutes, and the reaction mixture was aged for 1 hour. Cooled.

In this way, soap-free cation-reactive resin fine particles (3) having an ethylenically unsaturated bond in the shell portion, an average particle size of 1.1 μm, and a C/S ratio of 8/2 were obtained.

Example 4 (Crosslinked melamine particles by post-emulsification) A glass reactor equipped with a thermometer, a reflux condenser, a nitrogen gas inlet tube and a stirrer was placed in a glass reactor equipped with a water-soluble acrylic resin “Kotax WE-804” (Toray Co., Ltd.). company, solid content 50%) 91
100 parts of melamine resin "Yuban 22" (manufactured by Mitsui Toatsu Chemical Industry Co., Ltd., solid content 50%) and 1.4 parts of triethylamine were added, and while stirring the mixture thoroughly, 308 parts of deionized water was gradually added. , the mixture was emulsified. Next, remove the solvent under reduced pressure while replenishing deionized water.
The reaction solution was kept at 60° C. for one week and cooled after the reaction. In this way, crosslinked core particles were obtained in the first step.

[0076] Then, the reaction solution was heated for 8 hours while passing nitrogen gas.
The temperature was raised to 1 to 85°C, and a monomer mixture consisting of 8 parts of the polyfunctional monomer (A) obtained in Production Example 2 and 2.5 parts of methyl methacrylate, 20 parts of deionized water, and azobiscyanovaleric acid was added. An aqueous initiator solution consisting of 0.2 parts of dimethylethanolamine and 0.13 parts of dimethylethanolamine was added dropwise over 15 minutes from separate dropping ports, and the reaction solution was
After aging for an hour, it was cooled. In this way, emulsion polymerization was carried out in the second step to obtain reactive resin fine particles (4) having an ethylenically unsaturated bond in the shell portion, an average particle size of 0.12 μm, and a C/S ratio of 9/1.

Example 5 (Dispersion of reactive resin particles) A stainless steel beaker was charged with 80 parts of styrene, and an emulsified aqueous solution of the reactive resin particles (1) obtained in Example 1 was freeze-dried. 20 parts of the powder thus obtained were added while stirring with a disburr to obtain a styrene dispersion of reactive resin fine particles (1). This was a milky white, good particle dispersion with a viscosity of 95 poise.

Comparative Example 1 (Single-layer crosslinked particles) 215 parts of deionized water and 10 parts of the emulsifier obtained in Production Example 1 were placed in a glass reactor equipped with a thermometer, a reflux condenser, a nitrogen gas inlet tube, and a stirrer. 1 part of dimethylethanolamine and 1 part of dimethylethanolamine, and while blowing nitrogen gas, the mixture was heated to 8 parts.
The temperature was raised to 1-85°C.

Next, a mixture of 60 parts of styrene and 40 parts of ethylene glycol dimethacrylate and an aqueous initiator solution of 20 parts of deionized water, 1 part of azobiscyanovaleric acid, and 0.64 parts of dimethylethanolamine were each added. The solution was added dropwise from another dropping port over 60 minutes, and the reaction solution was aged for 1 hour and then cooled.

[0080] In this way, styrenic single-layer crosslinked resin particles (5) having an average particle diameter of 0.06 μm were obtained. Comparative Example 2 (Particles without reactive groups) 213 parts of deionized water and emulsifier "Eleminol JS2" (Sanyo Chemical Co., Ltd. 5.5 parts of each product (manufactured by Manufacturer Co., Ltd.) and heated the mixture to 81-85°C while blowing nitrogen gas.
The temperature rose to . Next, a monomer mixture consisting of 30 parts of styrene, 10 parts of n-butyl acrylate, and 10 parts of neopentyl glycol dimethacrylate, and 2 parts of deionized water were added.
0 parts of azobiscyanovaleric acid, and half of an aqueous initiator solution consisting of 1 part of azobiscyanovaleric acid and 0.64 parts of dimethylethanolamine were added dropwise from separate dropping ports over a period of 30 minutes. In this way, crosslinked core particles were obtained in the first step.

Next, a monomer mixture consisting of 32.5 parts of methyl methacrylate and 17.5 parts of n-butyl acrylate and the remaining half of the above-mentioned aqueous initiator solution were added dropwise from separate dropping ports over a period of 30 minutes. 1 of the reaction solution
After aging for an hour, it was cooled.

In this way, the shell part has no ethylenically unsaturated bonds, the average particle size is 0.06 μm, and C/S=5/5.
Core/shell type crosslinked resin particles (6) were obtained.

Comparative Example 3 (Single-layer crosslinked particles having reactive groups) Into a glass reactor equipped with a thermometer, a reflux condenser, a nitrogen gas inlet tube, and a stirrer, 215 parts of deionized water and the same method as in Production Example 1 were added. 10 parts of the obtained emulsifier and 1 part of dimethylethanolamine were each charged, and the mixture was heated to 81 to 85°C while nitrogen gas was passed through. Next, a monomer mixture consisting of 40 parts of methyl methacrylate, 20 parts of n-butyl acrylate, 10 parts of ethylene glycol dimethacrylate, and 10 parts of the polyfunctional monomer (A) obtained in Production Example 2, 20 parts of deionized water, and azobis An aqueous initiator solution consisting of 1 part of cyanovaleric acid and 0.64 parts of dimethylethanolamine was added dropwise from separate dropping ports over 60 minutes, and the reaction solution was aged for 1 hour and then cooled.

In this way, single-layer crosslinked particles (7) having an ethylenically unsaturated bond and having an average particle size of 0.09 μm were obtained.

(b) Thermosetting resin composition and molded product Example 6 - Unsaturated polyester resin
1,
000g (“Yupika 7661” manufactured by Japan Yupika Co., Ltd.)・
Silane coupling agent treated glass powder
2,500g (
Reactive resin particles (2) obtained in Example 2 (refractive index 1.548, “M-27-S” manufactured by Nippon Fellow Co., Ltd.)
12
0g (Refractive index 1.53) Magnesium oxide

10g・Zinc stearate

50g tert-butyl peroctoate
10g chopped strand glass (length 13mm)
150g (total)


3,840gi) The raw materials of the above formulation were put into a kneader with an internal volume of 5 liters and kneaded for 10 minutes.

[0086] The kneaded product was taken out of the kneader and first wrapped in a polyethylene film, then wrapped in an aluminum-deposited polyethylene terephthalate film and sealed. Put the double-wrapped kneaded product into a drying oven and heat it to 45°C.
It was aged for 20 hours. In this way, a press molding composition (2) which had increased in viscosity and became hard was obtained.

ii) After removing the packaging film from composition (2), cut this composition (2) into an appropriate size,
Charge a predetermined amount onto the press mold and apply a clamping pressure of 6.
0 kg/cm2: Press molding was performed at a molding temperature of 130° C. for 5 minutes to obtain a molded product (2) having the shape shown in FIG. This molded product (2) had no cracks, sink marks, or warpage, and had excellent surface gloss and high transparency.

Example 7 - Unsaturated polyester resin
1,
000g (“Yupika 7661” manufactured by Japan Yupika Co., Ltd.)・
aluminum hydroxide
2
, 500g (Refractive index 1.567, “Hygilite H
-320” (manufactured by Showa Denko)・Reactive resin particles (2) obtained in Example 2
120g (Refractive index 1.53) Magnesium oxide

10g・Zinc stearate

50g tert-butyl peroctoate
10g chopped strand glass (length 13mm)
150g (total)


3,840 g of the above-mentioned raw materials were kneaded and aged in the same manner as in step i) of Example 6 to obtain press molding composition (2). This composition (2) was press-molded in the same manner as in step ii) of Example 6 to obtain a molded article (2).

This molded product (2) had no cracks, sink marks, or warpage, and had excellent surface gloss and transparency, but its transparency was slightly inferior to that of the molded product (2).

Example 8 - Unsaturated polyester resin
1,
000g (“Yupica 7520” manufactured by Japan Yupica Co., Ltd.)・
aluminum hydroxide
1
, 500g (Refractive index 1.567, “Hygilite H
-320” (manufactured by Showa Denko)・Reactive resin particles (1) obtained in Example 1
150g (Refractive index 1.48) Magnesium oxide

10g・Zinc stearate

50g tert-butyl peroctoate
10g chopped strand glass (length 13mm)
400g (total)


3,120gi) chopped strand glass 40
The above-mentioned raw materials except for 0g were placed in a container with an internal volume of 5 liters, stirred and mixed with a dissolver for 5 minutes, and SMC
It was made into a premix for use. Pour this premix onto a polypropylene film until the thickness of the premix is approx.
It was spread out to a size of mm to obtain a premix sheet. Next, this premix sheet was cut in half at the center to obtain two premix sheets. Place one premix sheet with the premix side facing up, sprinkle 400g of chopped strand glass evenly on the premix side, and then place another premix sheet on the same side. Lay them on top of each other with the sides facing down. In this way, a sandwich-like sheet in which glass fibers were sandwiched between premix sheets was obtained.

[0091] This sandwich-like sheet is spaced 4 mm apart.
The glass fibers were thoroughly impregnated into the premix by three passes between two rolls. This sheet was wrapped and sealed in aluminum-deposited polyethylene terephthalate film, placed in a drying oven, and aged at 45° C. for 20 hours. In this way, a press molding composition (2) which had increased in viscosity and became hard was obtained.

ii) After removing the packaging film from composition (2), cut this composition (2) into an appropriate size,
Remove the polypropylene film on both sides of the sheet, charge the specified amount onto the press molding die, and apply a mold clamping pressure of 60k.
g/cm2: Press molding was carried out at a molding temperature of 130° C. for 5 minutes to obtain a molded product (2) having the shape shown in FIG.

This molded article (1) had no cracks, sink marks, or warpage, and had excellent surface gloss and transparency almost equivalent to that of the molded article (2).

Example 9 Vinyl ester resin

1,000g (“Lipoxy RP-30” manufactured by Showa Kobunshi Co., Ltd.) / Silane coupling agent treated glass powder
2,500
g (refractive index 1.548, "M-27-S" manufactured by Nippon Fellow Co., Ltd.) - Reactive resin particles obtained in Example 1 (1)

120g (Refractive index 1.48) ・Zinc stearate

50g tert-butyl peroctoate
10g chopped strand glass (length 13mm)
150g (total)

3,830gi)
The above-mentioned raw materials were put into a kneader having an internal volume of 5 liters and kneaded for 10 minutes. The kneaded material taken out from the kneader was used as a press molding composition (2).

ii) This composition (2) was press-molded in the same manner as in step ii) of Example 6 to obtain a molded article (2).

This molded product (2) had no cracks, sink marks, or warpage, and had excellent surface gloss and transparency.

Example 10 - Unsaturated polyester resin
1,
000g (“Yupica 7660” manufactured by Japan Yupica Co., Ltd.)・
Trimethylolpropane trimethacrylate
300g aluminum hydroxide
3,00
0g (Refractive index 1.567, “Hygilite H-32
0” (manufactured by Showa Denko)・Reactive resin particles obtained in Example 3 (3)
250g (Refractive index 1.49) ・Zinc stearate

50g tert-butyl peroctoate
15g chopped strand glass (length 13mm)
250g (total)

4,865 g of the above-mentioned raw materials were kneaded in the same manner as in step i) of Example 9 to obtain press molding composition (2). This composition (2) was press-molded in the same manner as in step ii) of Example 6 to obtain a molded article (2).

This molded product (2) had slight cracks at the corners, but was free from warpage and had excellent surface gloss and transparency.

Comparative Example 4 - Unsaturated polyester resin
1,
000g (“Yupika 7661” manufactured by Japan Yupika Co., Ltd.)・
Silane coupling agent treated glass powder
2,500g (
Refractive index 1.548, "M-27-S" manufactured by Nippon Fellow Co., Ltd.) Liquid low shrinkage agent

300g (polystyrene dissolved in styrene, “Polylite PB-956” manufactured by Dainippon Ink Chemical Co., Ltd.)・Magnesium oxide

10g・Zinc stearate
5
0g tert-butyl peroctoate

10g chopped strand glass (length 13mm)
150
g (total)

4,020g of the above-mentioned raw materials in Example 6
The mixture was kneaded and aged in the same manner as in step i) to obtain a press molding composition (2). This composition (1) was added to step i of Example 6.
Press molding was performed in the same manner as in i) to obtain a molded product (■).

[0100] This molded product (■) had no cracks, sink marks, or warpage, and had excellent surface gloss, but the entire surface became cloudy and
It was unclear.

Comparative Example 5 - Unsaturated polyester resin
1,
000g (“Yupika 7661” manufactured by Japan Yupika Co., Ltd.)・
Silane coupling agent treated glass powder
2,500g (
Refractive index 1.548, “M-27-S” manufactured by Nippon Fellow Co., Ltd.)・Magnesium oxide

10g・Zinc stearate

50g tert-butyl peroctoate
10g chopped strand glass (length 13mm)
150g (total)

3,720g of the above-mentioned raw materials were kneaded and aged in the same manner as in step i) of Example 6 to form a press-molding composition (1).
I got it. This composition (2) was press-molded in the same manner as in step ii) of Example 6 to obtain a molded article (2).

This molded article (2) had transparency comparable to that of the molded article (2), but cracks occurred and a glossy surface could not be obtained.

Comparative Example 6 - Unsaturated polyester resin
1,
000g (“Yupika 7661” manufactured by Japan Yupika Co., Ltd.)・
aluminum hydroxide
2
, 500g (Refractive index 1.567, “Hygilite H
-320” (manufactured by Showa Denko)・Core obtained in Comparative Example 2/
Shell-shaped crosslinked resin particles (6)
120g (Refractive index 1.48) Magnesium oxide

10g・Zinc stearate

50g tert-butyl peroctoate
10g chopped strand glass (length 13mm)
150g (total)


3,840 g of the above-mentioned raw materials were kneaded and aged in the same manner as in step i) of Example 6 to obtain press molding composition (2). This composition (2) was press-molded in the same manner as in step ii) of Example 6 to obtain a molded article (2).

This molded article (2) had no cracks, sink marks, or warpage, and had surface gloss and transparency almost equivalent to that of the molded article (2), but it had drawbacks in water resistance, heat resistance, etc.

Comparative Example 7 - Unsaturated polyester resin
1,
000g (“Yupica 7520” manufactured by Japan Yupica Co., Ltd.)・
aluminum hydroxide
1
, 500g (Refractive index 1.567, “Hygilite H
-320” (manufactured by Showa Denko)・Styrenic single-layer crosslinked resin particles obtained in Comparative Example 1 (5)
200g Magnesium oxide

10g・Zinc stearate
5
0g tert-butyl peroctoate

10g chopped strand glass (length 13mm)
400g (total)

3,170 g of the above-mentioned raw materials were treated in the same manner as in step i) of Example 8 to obtain press molding composition (2). This composition (2) was press-molded in the same manner as in step ii) of Example 8 to obtain a molded article (2).

[0106] This molded product (2) had no cracks, sink marks, or warpage, and had excellent surface gloss, but the whole part became cloudy and
It was unclear.

Comparative Example 8 - Unsaturated polyester resin
1,
000g (“Yupica 7661” manufactured by Japan Upica Co., Ltd.)

Silane coupling agent treated glass powder
2,500g (refractive index 1.548, "M-27-S"
(manufactured by Nippon Fellow Co., Ltd.)
・Magnesium oxide

10g・Zinc stearate

50g tert-butyl peroctoate
10g chopped strand glass (length 13mm)
150g (total)


3,720 g of the above-mentioned raw materials were kneaded and aged in the same manner as in step i) of Example 6 to obtain a press-molding composition. This composition was press-molded in the same manner as in step ii) of Example 6 to obtain a molded product.

[0108] This molded article had transparency comparable to molded article (2), but cracks occurred and a glossy surface could not be obtained.

Comparative Example 9 - Unsaturated polyester resin
1,
000g (“Yupika 7661” manufactured by Japan Yupika Co., Ltd.)・
aluminum hydroxide
2
, 500g (Refractive index 1.567, “Hygilite H
-320” manufactured by Showa Denko Co., Ltd.) Acrylic-styrene copolymer fine particles
120g (Refractive index 1.56, no surface functional groups, “Nippe Microgel” manufactured by Nippon Paint Co., Ltd.)・Magnesium oxide

10g・Zinc stearate

50g
・Tertiary butyl peroctoate
10
g. Chopped strand glass (length 13mm)
150g
(total)

3,840 g of the above-mentioned raw materials were kneaded and aged in the same manner as in step i) of Example 6 to obtain a press-molding composition. This composition was press-molded in the same manner as in step ii) of Example 6 to obtain a molded product.

This molded product had no cracks, sink marks, or warpage, and had surface gloss and transparency almost equivalent to molded product (2), but it had drawbacks in water resistance, heat resistance, etc.

Comparative Example 10 - Unsaturated polyester resin
1,
000g (“Yupica 7520” manufactured by Japan Yupica Co., Ltd.)・
aluminum hydroxide
1
, 500g (Refractive index 1.567, “Hygilite H
-320” manufactured by Showa Denko Co., Ltd.) Acrylic-styrene copolymer fine particles
120g (Refractive index 1.56, no surface functional groups, “Nippe Microgel” manufactured by Nippon Paint Co., Ltd.)・Liquid low shrinkage agent

300g (Polystyrene dissolved in styrene, "Yupica A-02" manufactured by Nippon Upica Co., Ltd.)
・Magnesium oxide

10g・Zinc stearate

50g・
Tert-butyl peroctoate
10g
・Chopped strand glass (length 13mm)
400g
(total)

3,270 g of the above-mentioned raw materials were treated in the same manner as in step i) of Example 8 to obtain a press molding composition. This composition was press-molded in the same manner as in step ii) of Example 8 to obtain a molded product.

This molded product had no cracks, sink marks, or warpage and had excellent surface gloss, but the entire molded product was cloudy and opaque.

(c) Molded product quality test test 1 (
Transparency and Moldability) A 50 mm x 50 mm (thickness 5 mm) plate piece was cut out from each formed product and used as a test piece. Place this test piece on the white part of the opacity test paper certified by the Japan Paint Inspection Association, and place it on top of the white part of the opacity test paper certified by the Japan Paint Inspection Association.
The values of Lw, aw, and bw were measured by contacting the colorimeter with the colorimeter. Next, transfer the test piece to the black part of the test paper,
Similarly, the values of Lb, ab, and bb were measured. 2
The color difference ΔEwb was calculated using the following formula, and the transparency was determined. Here, the larger the value of ΔEwb, the greater the transparency.

[0114]

[Math 1]

[0115] The moldability of each test piece was also visually examined.

The results of these tests are summarized in Table 1.

[0117]

[Table 1]

[0118] Moldability (presence or absence of cracks)
Visual transparency◎ No cracks
◎ Extremely high transparency ○ Small cracks at the corners ○ High transparency × Large cracks
Δ Translucent x Opaque As is clear from Table 1, it is recognized that each molded article of the example has excellent moldability and transparency compared to that of the comparative example.

Test 2 (Water Resistance) A plate piece of 80 mm x 80 mm (thickness 5 mm) was cut out from each molded product and used as a test piece. Using the hot water test apparatus shown in FIG. 2, a continuous hot water test was conducted for 200 hours in hot water at 97°C. In Figure 2, (1) is a constant temperature water tank, (
2) indicates hot water, (3) indicates a thermometer, (4) indicates a hot water exposure port, (5) indicates a test piece, and (6) indicates a vise.

[0120] The transparency ΔEwb was determined for each test piece that was left at room temperature for 24 hours before the hot water treatment and after the completion of the hot water treatment in the same manner as in the comparison of transparency above. Next, the rate of change in ΔEwb before and after hot water treatment was determined, and hot water resistance was determined from the degree of deterioration in transparency. In addition, changes in surface conditions were visually observed.

The results of this test are shown in Table 2.

[0122]

[Table 2]

Rate of change in △Ewb before and after hot water treatment Judgment of hot water resistance ◎ Extremely excellent ○ Excellent × Defective As is clear from Table 2, each molded product of the example was compared with that of the comparative example. It is recognized that it has excellent hot water resistance.

Test 3 (Heat resistance) A 50 mm x 50 mm (thickness 5 mm) plate piece was cut out from each molded product and used as a test piece. 200 pieces of this test piece
The test piece was heated for 10 minutes in a drying oven at .degree. C., then taken out from the drying oven and cooled at room temperature, and the degree of discoloration and change in transparency of the test piece was visually observed.

The results of this test are shown in Table 3.

[0126]

[Table 3]

Heat Resistance Judgment ◎ Very Excellent ○ Excellent × Poor As is clear from Table 3, it is recognized that each molded article of the example has superior heat resistance compared to that of the comparative example.

Test 4 (Cigarette Resistance) Cigarettes dried in a drying oven at 80° C. for 2 hours were used as tobacco for the cigarette resistance test. A lit cigarette was placed on each molded product and left for 10 minutes, then the burnt residue and ashes were removed, the tar was washed off with acetone, and changes in the condition of the area where the cigarette had been placed were visually observed.

The results of this test are shown in Table 4.

[0130]

[Table 4]

Judgment of Cigarette Resistance ◎ Very Excellent ○ Excellent × Poor As is clear from Table 4, it is recognized that each molded article of the Examples has superior cigarette resistance compared to that of the Comparative Examples.

[0132]

[Effects of the Invention] Since the reactive resin fine particles according to the present invention have the ethylenically unsaturated bond (b) remaining in the shell portion without being copolymerized, it is possible to copolymerize with the ethylenically unsaturated bond (b). The fine particles are blended with a monomer or thermosetting resin having at least one ethylenically unsaturated group to form a monomer dispersion or a thermosetting resin composition, and when performing a curing reaction, the above ethylenically unsaturated group is added. The unsaturated bond (b) is copolymerized with the ethylenically unsaturated group, the reactive resin fine particles are chemically bonded to the matrix, and the fine particles function as a shrinkage reducing agent. Therefore, it is possible to completely prevent the phenomenon that light is scattered at the interface between the reactive resin fine particles and the matrix and the transparency is impaired.

[0133] Further, by chemically bonding the reactive resin fine particles and the matrix as described above, the durability such as heat resistance and water resistance of the obtained molded article can be greatly improved.

[0134] Thus, by using the above-mentioned reactive resin fine particles of the present invention, curing shrinkage of the resin can be reliably suppressed, and a molded article that is highly transparent and has excellent durability and dimensional stability can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a molded product of Example 6 according to the present invention.

FIG. 2 is a vertical sectional view showing the structure of the hot water test device.

Claims (17)

[Claims] [Claim 1] Degree of crosslinking is 0.05 to 2.0 mmol/
It consists of a core particle made of a three-dimensionally crosslinked resin having a range of At least one of mono-substituted and 1,1-di-substituted radically polymerizable ethylenically unsaturated bonds (a) and 1,2-di-substituted, 1,1,2-tri-substituted and 1,1,2-substituted, A single or a mixture of polyfunctional monomers (A) each having at least one of the 2-tetra-substituted radically polymerizable ethylenically unsaturated bonds (b) and a non-aromatic radically polymerizable monomer. (B) Reactive resin fine particles obtained by polymerizing either alone or in a mixture. 2. The core particles emulsify a vinyl polymerizable monomer and a crosslinkable monomer having at least two copolymerizable ethylenically unsaturated bonds in an amount such that the degree of crosslinking is 0.05 to 2.0 mmol/g. Fine particles according to claim 1, which are formed by polymerization. [Claim 3] The core particle is a polyfunctional monomer (A)
, a radically polymerizable monomer (B), and 1 in the molecule
- At least one of monosubstituted and 1,1-disubstituted radically polymerizable ethylenically unsaturated bonds
2. Fine particles according to claim 1, which are formed by emulsion polymerization of a mixture of polyfunctional monomers (C). 4. The polyfunctional monomer (A) is an acrylic or methacrylic ethylenically unsaturated bond (a)
and a maleic acid-based or fumaric acid-based ethylenically unsaturated bond (b). 5. Fine particles according to claim 1, wherein the proportion of the polyfunctional monomer (A) in the total monomers for forming the shell is in the range of 1 to 50%. 6. Fine particles according to claim 1, having an average particle size in the range of 0.01 to 5 μm. 7. The fine particles according to claim 1, wherein the weight ratio of the core particle to the shell part is in the range of core particle/shell part (C/S)=10/90 to 99/1. 8. The reactive resin fine particles according to one of claims 1 to 7 contain a monomer having at least one ethylenically unsaturated bond copolymerizable with the radically polymerizable ethylenically unsaturated bond (b); A dispersion formed by dispersing 1 to 40 parts of this in a monomer group containing at least one kind. [Claim 9] The degree of crosslinking is 0.05 to 2.0 mmol/
The first step is to synthesize a core particle made of a three-dimensionally crosslinked resin in the range of g, and 1-monosubstitution or 1,1-
Di-substituted radically polymerizable ethylenically unsaturated bond (a)
at least one of the following, and 1,2-di-substituted, 1,1,2
- a single or a mixture of polyfunctional monomers (A) each having at least one of tri-substituted and 1,1,2,2-tetra-substituted radically polymerizable ethylenically unsaturated bonds (b); , a second step of polymerizing a non-aromatic radically polymerizable monomer (B) alone or in a mixture to form a shell portion having a radically polymerizable ethylenically unsaturated bond on the surface of the core particle. Method for producing reactive resin fine particles. 10. A thermosetting resin composition for thermoforming, comprising a thermosetting resin, an inorganic filler, and reactive resin fine particles according to one of claims 1 to 7. 11. A composition according to claim 10, wherein the thermosetting resin is an unsaturated polyester resin, a thermosetting acrylic resin or a vinyl ester resin. 12. A composition according to claim 10, wherein the inorganic filler is a glass powder with a refractive index in the range from 1.46 to 1.60. 13. A composition according to claim 10, wherein the inorganic filler is aluminum hydroxide. 14. A composition according to claim 10, wherein the inorganic filler is a mixture of glass powder and aluminum hydroxide with a refractive index in the range from 1.46 to 1.60. 15. The composition according to claim 10, wherein the inorganic filler is surface-treated with a silane coupling agent. 16. The reactive resin fine particles are 0.01 to 5 μm.
11. A composition according to claim 10 having an average particle size in the range of m and a refractive index in the range of 1.46 to 1.60. 17. The composition according to claim 10, which contains 100 to 400 parts of an inorganic filler and 5 to 30 parts of reactive resin fine particles based on 100 parts of the thermosetting resin.