JP2003089709A - Thermosetting resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an unsaturated polyester resin composition having a low smell and high safety and excellent curability, drying property, strength properties and workability in lamination molding. SOLUTION: This thermosetting resin composition comprises a dicyclopentadiene-modified unsaturated polyester oliogomer (A), an ester compound (B) containing a cyclohexene ring and an allyl ether group and a hydroxyalkyl methacrylate (C) containing a 1-4C alkyl group as essential components.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a styrene odor which is a problem when laminating and molding a fiber reinforced thermosetting resin (FRP),
The present invention relates to a thermosetting resin composition that improves flammability, has low odor, is highly safe, and has excellent curability, drying properties, strength properties, and workability.

[0002]

2. Description of the Related Art Conventionally, unsaturated polyester resins for laminate molding have been widely used for FRP molded products because of their excellent moldability, mechanical, scientific, physical and electrical properties. Its main applications are bathtubs, unit baths, boats, fishing boats, tanks, vehicles, housings and the like. In such unsaturated polyester resin, a styrene monomer is often used as a crosslinkable monomer from the viewpoint of curability, physical properties and the like. However, in recent years, in terms of environmental issues, volatile,
There is an increasing social movement to regulate the use of styrene monomer, which causes problems such as odor and toxicity.

To solve this problem, (1) a method of lowering the molecular weight of the unsaturated polyester to reduce the content of the styrene monomer, and (2) a method of adding wax or the like to the unsaturated polyester resin to suppress the volatilization of the styrene monomer. , (3)
Although a method of using a monomer having low volatility as an alternative to the styrene monomer has been proposed, as for (1) and (2), since the styrene monomer is contained, it is not a drastic measure. Regarding 3), no satisfactory one has been obtained in terms of odor, curability, dryability, strength physical properties, and workability in laminate molding.

Air-curable unsaturated polyesters containing allyl ether groups have been proposed, but MMA and alkyl (meth) acrylates such as butyl acrylate may also be used as a crosslinking monomer other than styrene. Although suggested, there is a problem that the odor is strong and the safety is low.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an unsaturated polyester resin composition having low odor, high safety, curability, drying properties, strength properties, and workability in laminate molding. Is.

[0006]

The present inventors have completed the present invention as a result of intensive research on these problems.

That is, the present invention provides a dicyclopentadiene-modified unsaturated polyester oligomer (A), an esterified product (B) having a cyclohexene ring and an allyl ether group.
And a thermosetting resin composition containing a hydroxyalkyl methacrylate (C) having an alkyl group having 1 to 4 carbon atoms as an essential component.

Next, the present invention will be described in detail.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The dicyclopentadiene-modified unsaturated polyester oligomer (A) used in the present invention is a so-called air-drying compound which can be cured in air and has an unsaturated bond. It is a polyester oligomer to which dicyclopentadiene is added, and is usually obtained from dicyclopentadiene, a dibasic acid containing αβ-unsaturated dicarboxylic acid as a main component, and glycol. As the oligomer (A), those having a number average molecular weight of about 550 to 800 are preferable, and those having 20 to 40 mol% of dicyclopentadiene in the molecule are preferable.

A preferred method for producing the dicyclopentadiene-modified unsaturated polyester oligomer (A) is as follows: 1 mol of dicyclopentadiene and αβ-unsaturated dicarboxylic acid such as maleic anhydride, and optionally other dicarboxylic acid such as phthalic anhydride. 1 mol of dibasic acid consisting of 2 parts by weight of water was added thereto to react, and then dicyclopentadiene-added dibasic acid 2
A manufacturing method in which 1 mol of glycol is reacted with respect to mol can be mentioned. The production method is not limited in any way, and depending on the case, the terminal carboxyl group of the esterified product obtained by reacting 1 mol of glycol with 2 mol of the dibasic acid and condensing and adding an acid to both ends of glycol can be used. A production method in which dicyclopentadiene is added can also be adopted. Of course, the amount of any one of the above-mentioned raw materials used is 1 to 2 more than the amount of the other raw materials within a range not impairing the effects of the present invention.
It goes without saying that it can be increased or decreased by about a percentage.

The dibasic acid used for preparing the dicyclopentadiene-modified unsaturated polyester oligomer (A) is preferably an acid anhydride, for example, maleic anhydride, citraconic anhydride, itaconic anhydride, halogenated anhydride. Containing αβ-unsaturated dicarboxylic acid such as maleic acid as the main component, and optionally other dicarboxylic acid such as phthalic anhydride, halogenated phthalic anhydride, hexahydrophthalic anhydride, 2,3-naphthalenedicarboxylic anhydride Is.

Examples of glycols include ethylene glycol, diethylene glycol and triethylene glycol.
, Polyethylene glycol, propylene glycol,
Dipropylene glycol, polypropylene glycol,
2-Methyl-1,3-propanediol, 1,3-butanediol, neopentyl glycol, hydrogenated bisphenol A, 1,4-butanediol, bisphenol A
And propylene oxide or ethylene oxide adduct, 1,2,3,4-tetrahydroxybutane, glycerin, trimethylolpropane, 1,3-propanediol, 1,2-cyclohexane glycol, 1,3-cyclohexane Glycol, 1,4-cyclohexane glycol, 1,4-cyclohexane dimethanol, paraxylene glycol, bicyclohexyl-4,4'-diol, 2,6-decalin glycol, 2,7-decalin glycol and the like can be mentioned.

The ester compound (B) having a cyclohexene ring and an allyl ether group in the molecule used in the present invention is esterified by using a cyclohexene ring-containing dibasic acid and a hydroxyl group-containing compound having an allyl ether group as essential components. What is obtained by the reaction is preferable, and in that case, the cyclohexene ring-containing dibasic acid and the allyl ether compound having a hydroxyl group may be used in combination with the above-mentioned other dibasic acid and / or glycol. What is available can also be used.

As the cyclohexene ring-containing dibasic acid,
Known and conventional ones can be used, and among them, tetrahydrophthalic anhydride and methyltetrahydrophthalic anhydride are particularly preferable.

As the hydroxyl group-containing compound having an allyl ether group, ethylene glycol monoallyl ether,
Diethylene glycol monoallyl ether, triethylene glycol monoallyl ether, polyethylene glycol monoallyl ether, propylene glycol monoallyl ether, dipropylene glycol monoallyl ether, tropropylene glycol monoallyl ether,
Polypropylene glycol monoallyl ether, 1,2
Butylene glycol monoallyl ether, 1,3 butylene glycol monoallyl ether, hexylene glycol monoallyl ether, octylene glycol monoallyl ether, trimethylolpropane diallyl ether,
There are glycerin diallyl ether, pentaerythritol triallyl ether, dipentaerythritol pentaallyl ether, dipentaerythritol triallyl ether and the like. Among them, pentaerythritol triallyl ether is particularly preferable.

As the ester compound (B) having a cyclohexene ring and an allyl ether group, those in which the number of moles of the allyl ether group per mole of the cyclohexene ring in the molecule is 0.9 or more, preferably 0.9 to 2 Particularly preferred is one obtained by adding 1 mol or more of a hydroxyl group-containing compound having an allyl ether group to 1 mol of a cyclohexene ring-containing dibasic acid.

In the present invention, an unsaturated polyester oligomer modified with dicyclopentadiene (A) and an esterified product (B) having a cyclohexene ring and an allyl ether group
The ratio of and is not particularly limited as long as the effect of the present invention is achieved. From the viewpoint of curability, particularly drying property, it is preferable to use an esterified product (B) having a large content of cyclohexene ring and allyl ether group in the molecule, and in that case, to the dicyclopentadiene-modified unsaturated polyester oligomer (A) The weight ratio of the ester compound (B) having a cyclohexene ring and an allyl ether group may be small. Further, in consideration of strength and hot water resistance, an esterified product (B) having a cyclohexene ring and an allyl ether group
Other αβ-unsaturated dicarboxylic acids and / or glycols may also be used in combination, and in this case, the cyclohexene ring and allyl ether group contents decrease, so it is better to increase the weight ratio of the ester compound (B) if necessary. Considering the above points, the weight ratio (A) / (B) = preferably 98/2 to 50/50, more preferably 95/5.
~ 50/50.

The thermosetting resin composition of the present invention may be combined with other unsaturated polyester, urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate or other radically polymerizable resin. . The amount of the radically polymerizable resin used is not particularly limited as long as it does not impair the effects of the present invention, but is preferably about 0 to 70% by weight based on the dicyclopentadiene-modified unsaturated polyester oligomer (A). is there.

The urethane (meth) acrylate is preferably a polyol such as polyether polyol, polyester polyol, polycarbonate carbonate or polybutadiene polyol, polyisocyanate or 2-polyisocyanate.
One or more hydroxyl groups per molecule such as hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate It is obtained by the reaction of a (meth) acrylate having 1 to 3, and has 2 or more (meth) acryloyl groups in one molecule.

The epoxy (meth) acrylate preferably has two or more (meth) acryloyl groups in one molecule, and is a bisphenol type or novolac type epoxy resin alone, or a bisphenol type and novolac type epoxy resin. Obtained by reacting an epoxy resin such as a resin mixed with a resin and an unsaturated monobasic acid such as acrylic acid, methacrylic acid, cinnamic acid, crotonic acid, maleic acid monoalkyl ester in the presence of an esterification catalyst. It is what is done.

The polyester (meth) acrylate is a saturated or unsaturated polyester having two or more (meth) acryloyl groups in one molecule, and a (meth) acrylic compound is added to the terminal of the saturated or unsaturated polyester. It was made to react. The number average molecular weight of the resin is preferably 500 to 5,000.

Hydroxyalkyl methacrylate (B) whose alkyl group used in the present invention has 1 to 4 carbon atoms
Examples thereof include hydroxymethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxybutyl methacrylate, with hydroxyethyl methacrylate being particularly preferred for odor and safety.

Other monomers may be used in combination with the above-mentioned hydroxyalkyl methacrylate (C) having 1 to 4 carbon atoms in the alkyl group as long as the effect of the present invention is not impaired. Of these, only typical ones are exemplified by styrene, α-methylstyrene, chlorostyrene, vinyltoluene, methylmethacrylate, diallylphthalate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, distyrene. Cyclopentenyloxyethyl (meth) acrylate, ethylene glycol monomethyl ether (meth) acrylate, ethylene glycol monobutyl ether (meth) acrylate, ethylene glycol monohexyl ether (meth)
Acrylate, ethylene glycol mono-2-ethylhexyl ether (meth) acrylate, diethylene glycol monomethyl ether (meth) acrylate,
Diethylene glycol monoethyl ether (meth) acrylate, diethylene glycol monobutyl ether (meth) acrylate, diethylene glycol monohexyl ether (meth) acrylate, ethylene glycol mono 2-ethylhexyl ether (meth) acrylate, neopentyl glycol di (meth) acrylate, PTMG di (Meth) acrylate, 1,3 butanediol dimethacrylate, 1,6 hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 2-hydroxy 1,3 dimethylcoloxypropane, 2,2 bis [4 -(Methacryloxyethoxy) phenyl] propane, 2,2bis [4- (methacryloxydiethoxy) phenyl] propane, 2,2bis [4- (methacryloxy) phenyl] propane Shi polyethoxy) phenyl] propane, tetraethylene glycol di (meth) acrylate, bisphenol AEO modified (N = 2) di (meth)
Examples thereof include acrylate, isocyanuric acid EO-modified (n = 3) di (meth) acrylate, and other monomers that can be crosslinked with a resin, or unsaturated oligomers thereof.

If the above-mentioned hydroxyalkyl methacrylate (C) is required to have improved physical properties such as hardness, heat resistance, abrasion resistance, scratch resistance, scorching resistance and chemical resistance, it is often used. Functionally unsaturated monomers, preferably trifunctional or higher functional (meth) acrylic acid ester monomers are preferably used in combination. Specifically, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane PO modified (n = 1) Tri (meth) acrylate, isocyanuric acid EO-modified (n = 3) tri (meth) acrylate, isocyanuric acid EO (n = 3) .ε-caprolactone-modified tri (meth) acrylate, dipentaerythritol pentar and hexa ( A polymerizable monomer such as (meth) acrylate and pentaerythritol tetra (meth) acrylate can also be used in combination.

The content of hydroxyethyl methacrylate is 60% by weight or more, preferably 80% by weight or more, particularly preferably 100% by weight in the hydroxyalkyl methacrylate (B) having an alkyl group having 1 to 4 carbon atoms. . When the content of hydroxyethyl methacrylate is in such a range, the low odor is improved, the resin viscosity is moderate, and the workability is good.

In the present invention, the weight ratio of the dicyclopentadiene-modified unsaturated polyester oligomer (A), the esterified product (B) and the hydroxyalkyl methacrylate (C) is (A + B) / (C) = 70/30. 30/7
The range of 0 is preferable, and 70/30 to 40 is more preferable.
/ 60. With such a weight ratio, the resin has an appropriate resin viscosity, good workability, etc., and excellent curability, dryability, and strength physical properties.

Examples of the curing accelerator include cobalt naphthenate, cobalt octylate, zinc octylate, vanadium octylate, copper naphthenate, barium naphthenate, and other metal soaps, vanadium acetyl acetate, cobalt acetyl acetate, iron acetyl acetonate. Metal chelates such as aniline, N, N-dimethylaniline,
N, N-diethylaniline, p-toluidine, N, N-
Dimethyl-p-toluidine, N, N-bis (2-hydroxyethyl) -p-toluidine, 4- (N, N-dimethylamino) benzaldehyde, 4- [N, N-bis (2-
Hydroxyethyl) amino] benzaldehyde, 4-
(N-methyl-N-hydroxyethylamino) benzaldehyde, N, N-bis (2-hydroxypropyl)-
p-toluidine, N-ethyl-m-toluidine, triethanolamine, m-toluidine, diethylenetriamine, pyridine, phenylimorpholine, piperidine, N,
N, N-substituted anilines such as N-bis (hydroxyethyl) aniline and diethanolaniline, N, N-substituted-p
Examples include amines such as -toluidine and 4- (N, N-substituted amino) benzaldehyde. In the present invention, amine-based and metal soap-based curing accelerators are preferred. The curing accelerator may be used in combination of two or more kinds, may be added to the resin in advance, or may be added at the time of use.

Examples of the polymerization inhibitor include trihydrobenzene, tolhydroquinone, 14-naphthoquinone,
Parabenzoquinone, hydroquinone, benzoquinone, hydroquinone monomethyl ether, p-tertiarybutylcatechol, 2,6-di-tertiarybutyl-4-methylphenol, copper naphthenate and the like can be mentioned. Preferably, it can be added to the resin composition in an amount of 5 to 1000 ppm. The polymerization inhibitor may be used in combination of two or more kinds.

Other various additives include viscosity modifiers such as viscosity reducers, thixotropic agents, thixotropic assistants, defoamers, leveling agents, silane coupling agents, air barrier agents such as paraffin, and the like, which are commercially available. Goods are available.

Examples of the radical curing agent include organic peroxides, specifically diacyl peroxide type, peroxy ester type, hydroperoxide type, dialkyl peroxide type, ketone peroxide type, peroxyketal type. Well-known and publicly known ones such as alkyl perester type and percarbonate type are used. The addition amount of the curing agent is preferably 0.1 to 6 parts by weight based on 100 parts by weight of the total amount of the resin composition. Further, the preferable addition amount of the curing accelerator is 0.1 to 5 parts by weight.

In the resin composition of the present invention, various additives such as a filler, an ultraviolet absorber, an antioxidant, a pigment, a shrinkage reducing agent, a pigment, a flame retardant, a stabilizer and a fiber reinforcing material are used. May be.

As the fiber reinforcing material that can be used, glass fiber, carbon fiber, aramid fiber, vinylon fiber, tetron fiber, metal fiber and the like can be used, and these may be used in combination. As the form of the fiber reinforcing material, a string-like, cloth-like, strand-like, milled fiber-like, whisker-like or the like can be used, and these may be used in combination. The amount of such fiber reinforcement used is not particularly limited, but is preferably 5 in the resin composition.
-60% by weight is suitable.

The resin composition of the present invention can be used for various purposes, but is particularly useful for FRP laminated molded products.

[0034]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples. Further, “part”, “%” and “ppm” in the text are based on weight unless otherwise specified.

Reference Example 1 (Preparation of Dicyclopentadiene Modified Unsaturated Polyester Oligomer (A)) In a 3 L glass flask equipped with a nitrogen gas introducing tube, a reflux condenser, a stirrer, and a dropping device, 1321 g of dicyclopentadiene, 980 g of maleic anhydride was charged, and heating was started under a nitrogen stream. At an internal temperature of 115 to 135 ° C,
180 g of water was added dropwise over 60 minutes, and the solid acid value was allowed to react up to 220 at that temperature and cooled to 100 ° C. Next, 542 g of diethylene glycol and 1 of hydroquinone
After charging 00 ppm and raising the temperature to 210 ° C., a dehydration condensation reaction was carried out by a conventional method, and the viscosity at dicyclopentadiene oligomer / styrene (SM) = 70/30 was KL and the acid value was 22 KOHmg / g. By the way, 50 ppm of P-tert-butyl catechol was added. Further 150
It cooled to ° C and the dicyclopentadiene modification unsaturated oligomer (UP-1) was obtained.

(Reference Example 2) (Preparation of esterified product (B)) 2 L equipped with a nitrogen gas introducing tube, a reflux condenser and a stirrer
866 g of pentaerythritol triallyl ether and 614 g of methyltetrahydrophthalic anhydride were charged into the glass flask of No. 3, and heating was started under a nitrogen stream. Inner temperature 1
A dehydration condensation reaction was carried out for 4 hours at 60 ° C. by a conventional method to obtain an esterified product (ADD-1).

Reference Example 3 (Preparation of Unsaturated Polyester) 2 L equipped with a nitrogen gas introducing tube, a reflux condenser and a stirrer
Propylene glycol 610 in a glass flask
g, maleic anhydride 392 g, and phthalic anhydride 592 g were charged, and heating was started under a nitrogen stream. Unsaturated polyester / SM with dehydration condensation reaction at 200 ℃
= 70/30, viscosity is Q to R, acid value is 25 KOHmg /
When g is reached, it is cooled to 180 ° C., toluhydroquinone 250 ppm, P-tertiarybutylcatechol 5
Add 0 ppm. Further cooling, an unsaturated polyester (UP-2) was obtained.

[Preparation of Thermosetting Resin Composition] (Example 1) 45 parts of the dicyclopentadiene-modified polyester oligomer (UP-1) obtained in Reference Example 1 and the esterified product (ADD) obtained in Reference Example 2 -1) Dissolve 5 parts in 50 parts of hydroxyethylmethacrylate to give 6%
0.5 parts of cobalt naphthenate (manufactured by Dainippon Ink and Chemicals),
1.0 part of Aerosil # 200 (manufactured by Nippon Aerosil) was blended.

(Example 2) Dicyclopentadiene-modified polyester oligomer (UP-1) 3 obtained in Reference Example 1
5 parts and the esterified product obtained in Reference Example 2 (ADD-
1) 15 parts was dissolved in 50 parts of hydroxyethyl methacrylate, and 0.5 parts of 6% cobalt naphthenate (manufactured by Dainippon Ink and Chemicals) and 1.0 part of Aerosil # 200 (manufactured by Nippon Aerosil) were blended.

Comparative Example 1 60 parts of the unsaturated polyester (UP-2) obtained in Reference Example 1 was mixed with 40 parts of styrene monomer.
0.5 parts of 6% cobalt naphthenate (manufactured by Dainippon Ink and Chemicals) and 0.8 parts of Aerosil # 200 (manufactured by Nippon Aerosil) were mixed.

Comparative Example 2 50 parts of the unsaturated polyester (UP-2) obtained in Reference Example 1 was dissolved in 50 parts of hydroxyethyl methacrylate to prepare 6% cobalt naphthenate (manufactured by Dainippon Ink and Chemicals). Part 5, Aerosil # 200
1.0 part (manufactured by Nippon Aerosil) was blended.

<Test Method and Evaluation> Evaluation of [Low Odor] The obtained resin composition was placed in an open container and placed 5c from the nose.
The odor felt at the position of m was judged as follows. Low odor judgment criteria ○ No odor at 5 cm from the nose △ 〃 slightly felt × 〃 strongly felt

Evaluation of [viscosity, degree of thixotropy] The obtained resin composition was measured by JIS-K using a BM type viscometer.
“Viscosity” and “thickness” were measured according to the test method of 4.5 of -6901.

Evaluation of [drying time, pot life] Further, methyl ethyl ketone peroxide (Permec N, manufactured by NOF CORPORATION) was added to 100 parts of the obtained resin composition in a glass beaker, and the mixture was stirred at 25 Three glass chop strand mats (manufactured by Nitto Boseki) having a weight of 450 g / m 2 were impregnated and defoamed on a glass plate coated with a release agent at ℃ to prepare a test plate. At that time, the lightness / weight of the roll work involved in impregnation and defoaming is referred to as “workability”, and the time when the adhesiveness of the laminated surface can be taken is referred to as “drying time”. Further, the time for the resin in the beaker to gel was defined as "pot life".

Evaluation of [Strength Physical Properties] The test plate obtained above was cured at 40 ° C. for 16 hours to obtain J
The strength properties were measured according to the IS test method.

[0046]

[Table 1] <Evaluation of low odor>

In the above table, β-HEMA is hydroxyethyl methacrylate, SM is styrene, 6% Co is 6% cobalt naphthenate, and SiO 2 is Aerosil # 200.

[0048]

[Table 2] <Evaluation of workability, etc.>

[0049]

[Table 3] <Evaluation of strength properties of FRP>

The hydroxyethyl methacrylate used in the present invention has a higher boiling point and a higher flash point than styrene as shown in the table below, and is highly safe.

[0051]

[Table 4]

[0052]

EFFECT OF THE INVENTION The present invention provides an unsaturated polyester resin composition for laminate molding, which has low odor, high safety, and excellent curability, drying properties, strength properties and workability.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kumiko Fukakusa             1-27 Hamadera Koencho, Sakai City, Osaka Prefecture, Park Sai             Dohama Temple 207 F-term (reference) 4J027 AB01 AB05 AB06 AB08 AB09                       AB13 AB14 AB15 AB16 AB17                       AB18 AB19 AB23 AB25 AE02                       AE03 AG03 AG04 AG05 BA05                       BA06 BA07 BA08 BA12 BA19                       BA22 BA24 BA26 CA38 CB03                       CB08 CD01

Claims (5)

[Claims] 1. A dicyclopentadiene-modified unsaturated polyester oligomer (A), an esterified product (B) having a cyclohexene ring and an allyl ether group, and a hydroxyalkyl methacrylate (C) having an alkyl group having 1 to 4 carbon atoms are essential. A thermosetting resin composition as a component. 2. A dicyclopentadiene-modified unsaturated polyester oligomer (A) comprises dicyclopentadiene and α
The thermosetting composition according to claim 1, which is obtained by using a dibasic acid containing β-unsaturated dicarboxylic acid as a main component and glycol and which contains 20 to 40 mol% of dicyclopentadiene in the molecule. Resin composition. 3. The thermosetting resin composition according to claim 1, wherein the hydroxyalkyl methacrylate (C) is hydroxyethyl methacrylate. 4. The weight ratio of the dicyclopentadiene-modified unsaturated polyester oligomer (A) and the esterified product (B) having a cyclohexene ring and an allyl ether group is (A) / (B) = 98/2 to 50/50. Claim 1
The thermosetting resin composition according to any one of 1 to 3. 5. The weight ratio of dicyclopentadiene-modified unsaturated polyester oligomer (A), esterified product (B) and hydroxyalkyl methacrylate (C) having an alkyl group having 1 to 4 carbon atoms is (A + B) / (C). ) = 70
It is / 30-30 / 70, The thermosetting resin composition in any one of Claims 1-4.