Technical Field The present invention relates to an ordinary temperature curable resin composition useful in various fields, a curing method of the resin composition and a cured product of the resin composition.

More specifically, the present invention relates to a resin composition which can be used for uses such as fiber reinforced plastic (hereinafter simply referred to as"FRP"), coating materials, casting molds and linings and does not require heating or the like for curing but is curable at an ordinary temperature. The present invention also relates to a curing method of the resin composition and a cured product of the resin composition.

Background Art Many radical curable resin compositions represented by an unsaturated polyester resin composition and a vinyl ester resin composition are being used for FRP products such as marine vessels, bathtubs and septic tanks. In particular, the vinyl ester resin composition having excellent chemical resistance is useful for corrosion- resistant equipment and is widely used not only for FRP but also for coating materials, casting molds, linings and the like.

The radical curable resin composition used for these uses usually contains approximately from 30 to 60 mass%

of styrene. The styrene is a crosslinking agent and at the same time, serves as a diluting agent. By controlling the amount of styrene used, the physical values such as viscosity of the resin composition can be freely controlled. Thus, styrene is an excellent monomer component.

For example, in the polyester resin composition (namely, a resin composition where an unsaturated polyester containing an a, ß-unsaturated polybasic acid (or an acid anhydride thereof) as one component and obtained by the esterification from a desired polyhydric alcohol using an optional polybasic acid (or an acid anhydride thereof) in combination is dissolved in a diluent such as styrene), the unsaturated polyester as the main component usually has a molecular weight (Mn) of approximately from 1,500 to 3,000 and this is a very highly viscous liquid, or nearly a solid, at an ordinary temperature. Therefore, it is difficult to mold the unsaturated polyester alone by a molding method. On use, the unsaturated polyester is diluted with from 30 to 60 mass% of styrene to reduce the viscosity and is thereby adjusted to a viscosity suitable for various molding methods. Styrene is a general industrial product and advantageously, is available at a low cost with ease.

The resin composition containing styrene has a polymerizable functional group and shows excellent curability and therefore, can be cured at an ordinary temperature and the cured product after curing this resin composition has good physical properties. Thus, the resin composition containing styrene has very excellent points.

However, the effect of styrene on the environment or human body is recently becoming a problem and reduction in the amount of styrene used is demanded. More specifically, when a polyester or vinyl ester resin composition containing styrene is molded by a hand lay-up or spray-up molding method or other molding method, the

styrene having high volatility cannot be prevented from volatilizing in the working environment. Styrene not only emits offensive odor but also is an objective chemical substance of the Japanese"Law Concerning Reporting, etc. of Release to the Environment of Specific Chemical Substances and Promoting Improvements in Their Management" (hereinafter simply referred to as"PRTR Law"). Therefore, reduction in the amount of styrene used, or no use of styrene, is being demanded in various fields.

This applies also to radical curable resin compositions such as unsaturated polyester resin composition and vinyl ester resin composition and various studies have been made in an attempt to develop a so- called"non-styrene"resin composition reduced in the amount of styrene used or not using styrene at all.

However, as long as an unsaturated polyester intrinsically high in the viscosity is used as the main component of the resin composition, it is an essential matter to reduce the viscosity using some diluent so as to ensure workability. That is, as long as an unsaturated polyester is used as the main component, use of styrene is unavoidable.

In place of a polyester resin composition containing styrene, the present inventors have made extensive investigations to use an oligoacrylate and/or an oligomethacrylate (hereinafter these are simply referred to as"oligo (meth) acrylate") having a relatively low viscosity for its molecular weight. However low the viscosity is, some diluent is necessary for ensuring satisfactory workability and although the amount of styrene used can be reduced, this is not yet satisfied.

The present inventors then investigated the use of allyl monomers represented by diallyl phthalate, as a diluent taking the place of styrene.

Allyl monomers generally have a low viscosity and a high boiling point and are faintly odorous and considered

to have less affect on the human body due to volatilization and therefore, this is a promising diluent. However, allyl monomers are low in the polymerizability and particularly, in comparison with styrene, the curability at an ordinary temperature is poor. Therefore, when this monomer is cured at an ordinary temperature, curing proceeds to gelling but does not reach complete curing.

Examples of conventional techniques for improving the curability of a radical curable resin composition containing an allyl monomer include one shown in Japanese Unexamined Patent Publication No. 3-195715 (JP-A-3- 195715). This patent publication describes an ordinary temperature curing method of an allyl-based polyester resin composition comprising an unsaturated polyester and an allyl monomer and using an organic hydroperoxide as a curing agent and a vanadium compound as an accelerator or using an organic ketone peroxide as a curing agent and a vanadium compound as an accelerator and also states that an allyl-based resin composition further containing a vinyl monomer is curable at an ordinary temperature.

In this patent publication, a special accelerator containing a vanadium compound is essential and it is revealed that curing is not attained by a commonly employed curing method using a combination of methyl ethyl ketone peroxide as a curing agent and cobalt naphthenate as an accelerator. Furthermore, a vinyl monomer is essential and in all of examples, styrene, methyl methacrylate or vinyl acetate having a high volatility is used as the vinyl monomer in an amount of 7 to 10 parts by mass per 100 parts by mass of the unsaturated polyester resin composition or vinyl ester resin composition. Thus, this technique does not provide an alternate of styrene.

On the other hand, representative examples of conventional techniques for improving curability of a radical curable resin composition include Japanese

Unexamined Patent Publication No. 1-254722 (JP-A-1- 254722). This patent publication describes a technique where at the time of curing an unsaturated polyester resin composition or a vinyl ester resin composition by adding a curing agent, even if the amount added of cobalt naphthenate as a general accelerator is reduced to a level of usually not causing a curing reaction, when an aliphatic acetamide compound is added as a curing accelerator, a curing reaction takes place at an ordinary temperature and a cured product is obtained.

However, in this patent publication, the curability of a resin composition containing an allyl monomer having an allyl group, which is extremely different in the polymerizability from the vinyl group, is not discussed at all and the object thereof is merely to improve the curability when the amount of the accelerator used is reduced.

As such, there are not yet known any means capable of satisfactorily solving reduction in the curability, particularly, reduction in the curability at an ordinary temperature, which becomes a problem in a radical curable resin composition mainly comprising an oligo (meth) acrylate and using an allyl monomer as a diluent.

Disclosure of Invention An object of the present invention is to provide a novel radical curable resin composition obtained by diluting an oligo (meth) acrylate with an allyl monomer, where the problem of reduction in curability at an ordinary temperature is solved. Another object of the present invention is to provide a curing method of the resin composition. Still another object of the present invention is to provide a cured product of the resin composition.

As a result of extensive studies on the above- described problems, the present inventors have found that an acetoacetamide compound is effective in improving the

curability of a radical curable resin composition mainly comprising an oligo (meth) acrylate and using an allyl monomer as a diluent, and have accomplished the present invention.

The present inventors have also found that when an unsaturated polyester is added to the resin composition and the resin composition is cured, a cured product having higher strength can be obtained, and have accomplished the present invention.

More specifically, the present invention (I) provides an ordinary temperature curable resin composition comprising, (1) an oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule, (2) an allyl monomer of a saturated and/or unsaturated polybasic acid, and (3) an acetoacetamide compound.

The present invention (II) provides a curing method of the resin composition of the present invention (I).

The present invention (III) provides a cured product of the resin composition of the present invention (I).

The present invention comprises, for example, the following embodiments.

1. An ordinary temperature curable resin composition comprising, (1) an oligo (meth) acrylate having one or more (meth) acryloyl group within one molecule, (2) an allyl monomer of a saturated and/or unsaturated polybasic acid, and (3) an acetoacetamide compound.

2. A composition according to above item 1, which further comprises an unsaturated polyester.

3. A composition according to above item 1 or 2, wherein the oligo (meth) acrylate is a polyester- (meth) acrylate.

4. A composition according to above item 1 or 2, wherein the oligo (meth) acrylate is an ester of a

polyhydric alcohol having one or more (meth) acryloyl groups within one molecule.

5. A composition according to above item 1 or 2, wherein the oligo (meth) acrylate is at least one member selected from vinyl ester resin compositions which are a reaction product of a (meth) acrylic acid and an epoxy resin composition or a reaction product of a polyvalent phenol compound and an unsaturated epoxy compound.

6. A composition according to above item 1 or 2, wherein the oligo (meth) acrylate is a urethane- (meth) acrylate.

7. A composition according to above item 1 or 2, wherein the oligo (meth) acrylate is an oligo (meth) acrylate obtained by reacting (A) a composition containing a (meth) acrylic acid, an alkylene monoepoxide and a polybasic acid anhydride in the presence of (B) an organic and/or inorganic antimony compound at a temperature of 140 to 210°C.

8. A composition according to above item 1 or 2, wherein the oligo (meth) acrylate is an oligo (meth) acrylate obtained by reacting (A) a composition resulting from adding a polybasic acid anhydride to an unsaturated monoalcohol-containing composition obtained by the reaction between a (meth) acrylic acid and an alkylene monoepoxide, in the presence of (B) an organic and/or inorganic antimony compound at a temperature of 140 to 210°C.

9. A composition according to any one of above items 1 to 8, wherein the oligo (meth) acrylate has a mass average molecular weight of 150 to 3,000.

10. A composition according to any one of above items 1 to 9, which comprises antimony and/or an antimony compound.

11. A composition according to any one of above items 1 to 10, wherein the ratio of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule to (2) the allyl monomer of a

saturated and/or unsaturated polybasic acid is (1): (2) =1: 9 to 9: 1 in terms of weight ratio.

12. A composition according to any one of above items 1 to 11, wherein the amount of (3) the acetoacetamide compound is from 0.01 to 5 parts by mass per 100 parts by mass as a total of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule and (2) the allyl monomer of a saturated and/or unsaturated polybasic acid.

13. A composition according to any one of above items 1 to 12, wherein the amount of (4) the unsaturated polyester is from 5 to 500 parts by mass per 100 parts by mass as a total of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule and (2) the allyl monomer of a saturated and/or unsaturated polybasic acid.

14. A method for curing an ordinary temperature curable resin composition, comprising adding a curing agent to an ordinary temperature curable resin composition as claimed in any one of above items 1 to 13 and curing the composition at an ordinary temperature.

15. The method as claimed in above item 14, wherein the curing agent is an organic peroxide.

16. The method as claimed in above item 14, wherein the curing agent is a composite curing agent comprising an organic peroxide and a curing accelerator.

17. The method as claimed in above item 16, wherein the composite curing agent is at least one member selected from methyl ethyl ketone peroxide-cobalt naphthenate, benzoyl peroxide-N, N-dimethylaniline, and benzoyl peroxide-N, N-dimethylparatoluidine.

18. A cured product obtained by curing an ordinary temperature curable resin composition as claimed in any one of above items 1 to 13.

Best Mode for Carrying Out the Invention The present invention is described below. The "ordinary temperature curable resin composition"as used

in the present invention is described below.

The"ordinary temperature"in the ordinary temperature curing as used herein refers to a temperature region classified by the common use form. In general, the curing by charging a curing agent at a resin composition temperature of 50°C or less is classified into"ordinary temperature curing", the curing under heating at 50 to 100°C after the charging of a curing agent is classified into"medium temperature curing", and the curing under heating at 100°C or more after the charging of a curing agent is classified into"high temperature curing". The"curing"at an ordinary temperature curing means that the composition loses flowability due to crosslinking or polymerization reaction and is solidified from the molten state, and excludes the case where a thermoplastic resin composition or the like is, after fusing under heat, cooled and solidified.

For example, when a curing agent is charged into a resin composition having flowability, polymerization starts and at the same time, the viscosity gradually increases to provide a state called"gelling". As the polymerization further proceeds, the viscosity increases and the composition changes into a solid not having flowability at all. This process is called"curing".

The"ordinary temperature curing"does not always mean that the curing is performed at a temperature of 50°C or less throughout the curing process. After starting the curing at an ordinary temperature, the temperature may exceed 50°C due to heat of polymerization.

The polymerization speed is known to greatly vary depending on the temperature of resin composition or the kind or amount of curing agent, accelerator, acceleration aid or polymerization inhibitor. According to the temperature of a resin composition at molding, the curing time can be controlled by the kind or amount of curing

agent, accelerator, acceleration aid or polymerization inhibitor. However, the cured product may vary in the physical properties depending on the kind or amount of curing agent, accelerator, acceleration aid or polymerization inhibitor. Also, the viscosity varies depending on the temperature of resin composition. In order to obtain a viscosity suitable for molding and control the physical properties of the cured product, the resin composition is sometimes cured under heating at a temperature approximately from 20 to 30°C.

In the case of curing a radical curable resin composition at an ordinary temperature, it is known that the polymerization reaction proceeds even in the state that the generation of heat of curing is finished. This is called"postcuring". The condition where the postcuring is almost finished is called"complete curing" and in order to quickly reach complete curing, the molded article is heated.

For example, in the case of producing FRP by a hand lay-up molding method, the temperature of resin composition is adjusted to approximately from 15 to 25°C and a curing agent is charged into the composition. This resin composition is laminated by impregnation on a mat cloth or the like place in a mold. After a while, curing starts and heat is generated. After the completion of heat generation, the resin composition is in a solidified state. This composition is postcured by heating it at 60 to 80°C in a heating furnace and thereby, the complete curing is attained. In order to shorten the molding cycle, it is preferred that gelling starts within 24 hours to provide a state capable of after-curing. More preferably, the gelling starts within 1 hour. However, the gelling time is not particularly limited.

From the above, the"ordinary temperature curable resin composition"as used in the present invention refers to a resin composition such that a resin composition having flowability can be changed into a

solid having no flowability by charging a curing agent or the like at the resin composition temperature of 50°C or less. This does not limit to maintain the ordinary temperature through all steps in the curing of the resin composition of the present invention but the temperature may elevate accompanying heat generation due to heat of polymerization or an operation may be performed for postcuring.

Respective elements of the present invention (I) are described below.

(1) Oligo (meth) acrylate having one or more (meth) acryloyl group within one molecule The oligo (meth) acrylate for use in the present invention (I) is not particularly limited and any oligo (meth) acrylate can be used. According to the use form of the resin composition, various materials may be used from the standpoint of controlling the viscosity, curability or curing speed or by taking account of the molding method, however, the following materials are mainly used: (A) polyester- (meth) acrylate, (B) vinyl ester resin composition (epoxy- (meth) acrylate), (C) polyhydric alcohol- (meth) acrylate, and (D) urethane- (meth) acrylate.

Of course, in the resin composition of the present invention (I), one of these materials may be used and/or two or more thereof may be used in combination.

Furthermore, an oligo (meth) acrylate other than those described above may be used.

The materials (A) to (D) are described below.

(A) Polyester-(meth) acrylate The polyester- (meth) acrylate is an oligomer having a (meth) acryloyl group at the molecular terminal and preferably having a mass average molecular weight of 150 to 3,000, which is generally synthesized by the reaction of a polyester oligomer and a (meth) acrylic acid.

Examples of the production method of the polyester- (meth) acrylate include a method of esterifying an acrylic acid and/or a methacrylic acid (hereinafter, these are collectively called simply as" (meth) acrylic acid") with a polyhydric alcohol and a polybasic acid under heating at a temperature of 80 to 100°C together with a solvent capable of azeotropically removing water, such as benzene or toluene, in the presence of a sulfuric acid catalyst, neutralizing the sulfuric acid with an alkali after the completion of reaction, repeating water washing to remove salts produced, and then distilling off the solvent to obtain the objective polyester- (meth) acrylate, and a method of using a transesterification reaction between a methyl ester of polybasic acid and an unsaturated alcohol. These are described in detail in Polyester Jushi Handbook (Handbook of Polyester Resin), first ed., first imp. , pp. 187-189 (June 30,1988).

Other examples of the production method include the following method invented by the present inventors. This is a production method of an oligo (meth) acrylate, comprising performing a reaction at a temperature of 140 to 210°C in the presence of an organic and/or inorganic antimony compound.

This production method is described in detail below.

This production method is characterized in that raw materials of an oligo (meth) acrylate are reacted at a temperature of 140 to 210°C in the presence of an organic and/or inorganic antimony compound. Specific examples thereof include the following production methods (1) and (2).

Production Method (1) : A method of reacting (A) a composition containing a (meth) acrylic acid, an alkylene monoepoxide and a polybasic anhydride in the presence of (B) an organic and/or inorganic antimony compound at a temperature of 140 to 210°C.

Production Method (2) :

A method of reacting (A) a composition resulting from adding a polybasic acid anhydride to an unsaturated monoalcohol-containing composition obtained by the reaction between a (meth) acrylic acid and an alkylene monoepoxide, in the presence of (B) an organic and/or inorganic antimony compound at a temperature of 140 to 210°C The production method (1) more specifically includes a production method comprising the following first to third steps: First Step: a step of obtaining a starting material composition containing a (meth) acrylic acid, an alkylene monoepoxide and polybasic acid anhydride, Second Step: a step of reacting the starting material composition obtained in the first step, under heating in the presence of a catalyst in a closed system to obtain a reaction mixture (1), and Third Step: a step of reacting the reaction mixture (1) obtained in the second step, at a temperature of 140 to 210°C in the presence of an organic and/or inorganic antimony compound to obtain an oligo (meth) acrylate-containing resin composition.

The production method (2) more specifically includes a production method comprising the following first to fourth steps: First Step: a step of obtaining a starting material composition containing a (meth) acrylic acid and an alkylene monoepoxide, Second Step: a step of reacting the starting material composition obtained in the first step, under heating in the presence of a catalyst in a closed system to obtain a reaction mixture (2),

Third Step: a step of adding a polybasic acid anhydride to the reaction mixture (2) obtained in the second step to obtain a reaction mixture (3), and Fourth Step: a step of reacting the reaction mixture (3) obtained in the third step, at a temperature of 140 to 210°C in the presence of an organic and/or inorganic antimony compound to obtain an oligo (meth) acrylate-containing resin composition.

The polyester- (meth) acrylate as one of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule in the ordinary temperature curable resin composition of the present invention (I) is of course not limited to that produced by the above- described production methods and a polyester- (meth) acrylate produced by any production method may be used. However, the above-described production method of an oligo (meth) acrylate, comprising performing a reaction at a temperature of 140 to 210°C in the presence of an organic and/or inorganic antimony compound, is simple and easy as compared with conventional production methods of an oligo (meth) acrylate and therefore, is preferred as the production method of an oligo (meth) acrylate for use in the ordinary temperature curable resin composition of the present invention (I).

In the case of using an antimony compound as a catalyst in the synthesis of an oligo (meth) acrylate, it may be considered to separate and remove the antimony compound by distillation, extraction and/or other methods, however, the antimony catalyst used in the synthesis of an oligo (meth) acrylate may have been changed from the compound before use and for completely removing the compound, at least one or more of distillation, extraction and other separation methods must be performed, which may be expensive.

It is not known, at present, how the remaining

antimony affects the ordinary temperature curing, but the effect of the present invention is not conspicuously inhibited. In order to produce an oligo (meth) acrylate at a low cost, the resin composition is preferably used while containing the antimony. However, the present invention is not limited to contain antimony but the antimony may be separated and removed.

The antimony compound is known to be used as an additive for obtaining a flame retardant material and in the present invention, an antimony compound may be newly added in addition to the catalyst residue.

Specific examples of respective raw materials except for (a) the (meth) acrylic acid for use in the production of a polyester- (meth) acrylate include the followings.

Specific examples of (b) the alkylene monoepoxides include ethylene oxide, propylene oxide, butylene oxide, epichlorohydrin, epibromohydrin, allyl glycidyl ether, phenyl glycidyl ether, cyclohexene oxide, styrene oxide and glycidyl (meth) acrylate.

Specific examples of (c) the alkylene monoepoxide adduct of (meth) acrylic acid include compounds obtained by adding an acrylic acid and/or a methacrylic acid to the above-described alkylene monoepoxides.

Specific examples of (d) the polybasic acid and/or polybasic acid anhydride and/or polybasic acid ester include phthalic acid anhydride, orthophthalic acid, isophthalic acid, terephthalic acid, dimethyl orthophthalate, dimethyl isophthalate, dimethyl terephthalate, endomethylene tetrahydrophthalic acid anhydride, endomethylene tetrahydrophthalic acid, dimethyl endomethylenetetrahydrophthalate, methyltetrahydrophthalic acid anhydride, methyltetrahydrophthalic acid, dimethyl methyltetrahydrophthalate, adipic acid, dimethyl adipate, sebacic acid, trimellitic acid anhydride, trimellitic acid and tetramethyl trimellitate.

Specific examples of (e) the polyhydric alcohols

include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,3-propanediol, neopentyl glycol, 1,4-cyclohexane dimethanol, xylylene glycol, 1,3- butanediol, 1,4-butanediol, 2-methylpropanediol and pentaerythritol.

(B) Vinyl ester resin composition The vinyl ester resin composition as one of the oligo (meth) acrylate for use in the present invention (I) is described below. The vinyl ester resin composition is a resin composition having a (meth) acryloyl group at the molecular terminal and having a molecular weight of 500 to 3,000, which is generally synthesized by the addition reaction of an epoxy resin composition and a (meth) acrylic acid, and/or a composition obtained by dissolving the above-described resin composition in a reactive monomer, however, the"vinyl ester composition" as referred to in the present invention is defined not to contain a reactive monomer.

Examples of the epoxy resin composition used in the synthesis of the vinyl ester resin composition include the following types: (a) a bisphenol-type epoxy resin composition obtained by a dehalogenation reaction of various bisphenols represented by bisphenol A, and an epichlorohydrin, (b) a novolak-type epoxy resin composition synthesized from a novolak and an epichlorohydrin, and (c) a peracetic acid-type epoxy resin composition obtained by epoxidizing an unsaturated bond with peracetic acid.

Other vinyl esters are described in detail in Vinyl <BR> <BR> Ester Jushi (Vinyl Ester Resin), first ed. , first imp., pp. 7-21 (June 16,1993).

Also, an epoxy resin composition modified using a phenol, a saturated or unsaturated polybasic acid, a phosphoric acid, a urethane, a silicone, an allyl ether or a ketene dimer may be used so as to modify the

physical properties of the epoxy resin composition. The modification method of the epoxy resin composition is described in detail in Vinyl Ester Jushi (Vinyl Ester Resin), 1st ed. , 1st imp. , pp. 22-31 (June 16,1993).<BR> <P>(C) Polyhydric alcohol-(meth) acrylate The polyhydric alcohol- (meth) acrylate as one of the oligo (meth) acrylate for use in the present invention (I) and the present invention (II) is described below. The "polyhydric alcohol"as used herein is not only a general "polyhydric alcohol"but also includes a so-called "polyalkylene glycol".

The synthesis method of the polyhydric alcohol- (meth) acrylate includes the following production methods (3) to (5).

Production Method (3) : A method of esterifying a polyhydric alcohol or polyalkylene glycol and a (meth) acrylic acid to obtain a polyhydric alcohol- (meth) acrylate.

Production Method (4) : A method of transesterifying a (meth) acrylic acid ester and a polyhydric alcohol or polyalkylene glycol to obtain a polyhydric alcohol- (meth) acrylate.

Production Method (5) : A method of reacting a (meth) acrylic acid and an alkylene monoepoxide and further esterifying the reactant with a (meth) acrylic acid to obtain a polyhydric alcohol- (meth) acrylate.

The compounds used in these production methods (3) to (5) are not limited but specific examples of the general polyhydric alcohol include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,3-propanediol, neopentyl glycol, 1,4- cyclohexanedimethanol, xylylene glycol, 1,3-butanediol, 1,4-butanediol, 2-methylpropanediol, glycerin, pentaerythritol, trimethylolpropane and trimethylolmethane.

Specific examples of the polyalkylene glycol include

polyethylene glycol and polypropylene glycol.

Specific examples of the alkylene monoepoxide include ethylene oxide, propylene oxide, butylene oxide, epichlorohydrin, epibromohydrin, allyl glycidyl ether, phenyl glycidyl ether, cyclohexene oxide and styrene oxide.

(D) Urethane- (meth) acrylate The urethane- (meth) acrylate, as one of the oligo (meth) acrylates for use in the present invention (I), is described below.

The"urethane- (meth) acrylate" as used herein means a urethane compound having an unsaturated group and capable of radical curing. Specifically, this is, for example, a compound having one or more (meth) acryloyl group and two or more urethane bonds within one molecule and this compound is obtained by reacting a polyvalent isocyanate compound with, as one component, an unsaturated alcohol covalently having a (meth) acryloyl group and a hydroxyl group within one molecule, which is obtained by reacting an alkylene monoepoxide with a (meth) acrylic acid. Those obtained by adding to this compound a polyhydric alcohol or a polyester or polyether having a terminal hydroxyl group and reacting these are also included.

Examples of the polyvalent isocyanate compound which can be used in the urethane- (meth) acrylates include 2,6- tolylene diisocyanate, 2,4-tolylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, hexamethylene diisocyanate and hexamethylene diisocyanate trimer.

The molecular weight of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule for use in the ordinary temperature curable resin composition of the present invention (I) is not particularly limited. The molecular weight is preferably from 150 to 3,000 in terms of the weight average

molecular weight (hereinafter sometimes referred to as "molecular weight"). If the molecular weight is less than 150, the volatility may disadvantageously elevate, whereas if it exceeds 3,000, an extremely high viscosity may result and this is not preferred. The molecular weight is more preferably from 200 to 2,000, most preferably from 300 to 1,000.

The molecular weight of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule for use in the ordinary temperature curable resin composition of the present invention (I) can be measured by a known method. Specific examples of the measuring method include gel permeation chromatography.

This is described in detail, for example, in Shin Jikken Kagaku Koza 19 Kobunshi Kagaku II (New Experimental Chemistry Course, 19, Polymer Chemistry II), pp. 533-539 (September 20,1978).

(2) Allyl monomer of saturated and/or unsaturated polybasic acid Next, (2) the allyl monomer of a saturated and/or unsaturated polybasic acid which can be used in the present invention (I) is described.

The allyl monomer which can be used in the present invention is not particularly limited and any compound may be used if it has at least one allyl group within one molecule. In particular, allyl esters are preferred.

Specific examples of the allyl esters include diallyl orthophthalate, diallyl isophthalate, diallyl terephthalate, diallyl endomethylene tetrahydrophthalate, diallyl 1,4-cyclohexanedicarboxylate monomer, triallyl trimellitate, diallyl maleate and diallyl fumarate.

Other examples of the allyl monomer include triallyl isocyanurate and triallyl cyanurate.

Among these, although an allyl monomer is selected by taking account of easy availability, easy producibility, curability and physical properties of the cured product, preferred are diallyl orthophthalate,

diallyl isophthalate, diallyl terephthalate, diallyl maleate, diallyl fumarate and triallyl trimellitate. Of course, the present invention is not limited thereto.

Two or more of these allyl monomers may be used in combination.

(3) Acetoacetamide compound Then, (3) the acetoacetamide compound for use in the present invention (I) is described.

The acetoacetamide compound is not particularly limited and may be sufficient if it is a compound having any one of the structures represented by the following formulae (1) to (3) which are a so-called acetoacetamide structures. wherein R1, R2 and R3 each independently represents hydrogen or an alkyl group having from 1 to 10 carbon atoms, which may have a branch or a substituent. wherein R4 represents hydrogen or an alkyl group having from 1 to 10 carbon atoms, which may have a branch or a substituent, and Rs and R6 each independently represents hydrogen, an alkyl group having from 1 to 10 carbon atoms, which may have a branch or a substituent, or a phenyl group which may have a substituent, provided that at least one of R5 and R6 is a phenyl group which may have a substituent.

wherein R'represents hydrogen or an alkyl group having from 1 to 10 carbon atoms, which may have a branch or a substituent, Re and R9 combine with each other to form a 5-, 6-or 7-membered ring structure, the ring structure may contain, in addition to the carbon, one or more atom of oxygen, nitrogen and sulfur at an arbitrary position and may have a double bond at an arbitrary position, each element constituting the ring structure may have one or more alkyl group having from 1 to 10 carbon atoms, which may have a branch or a substituent, or one or more phenyl group which may have a substituent, and a bicyclo or tricyclo ring structure having the above-described ring structure as a part of the structure may also be formed.

Specific examples of the so-called aliphatic acetoacetamide compound represented by formula (1) include acetoacetamide, (N-methyl) acetoacetamide, (N, N- dimethyl) acetoacetamide, (N, N-diethyl) acetoacetamide, (N, N-diisopropyl) acetoacetamide, N, N- dibutylacetoacetamide, [N-methyl-N- (acetoacetoxyethyl) ] acetoacetamide and N, N- di (hydroxyethyl) acetoacetamide.

Specific examples of the so-called aromatic aceto- acetamide compound represented by formula (2) include N- methylacetoacetanilide and (N-acetoacetoxyethyl) aceto- acetanilide.

Specific examples of the so-called acetoacetyl heterocyclic compound represented by formula (3) include (1-acetoacetyl) pyrrole, (1-acetoacetyl) imidazole, (1- acetoacetyl) indole, (1-acetoacetyl) indazole, (7- acetoacetyl) purine, (9-acetoacetyl) carbazole, (10- acetoacetyl) phenothiazine, (10-acetoacetyl) phenoxazine, (l-acetoacetyl) pyrrolidine, (1-acetoacetyl) pyrroline, (1-

acetoacetyl) imidazolidine, (l-acetoacetyl) imidazoline, (l-acetoacetyl) pyrazolidine, (l-acetoacetyl) pyrazoline, (l-acetoacetyl) piperidine, (l-acetoacetyl) piperazine, 1, 4-di (acetoacetyl) piperazine, (l-acetoacetyl) indoline and (2-acetoacetyl) isoindoline.

Among these acetoacetamide compounds, preferred are aliphatic acetoacetamide compounds and acetoacetyl heterocyclic compounds, more preferred are N, N-dimethyl- acetoacetamide and (1-acetoacetyl) pyrrolidine.

Of course, two or more of these acetoacetamide compounds may be used in combination.

(4) Unsaturated polyester Finally, (4) the unsaturated polyester which can be used in the present invention (I) is described. The unsaturated polyester which can be used in the present invention (I) is not particularly limited if it is an unsaturated polyester having a molecular weight of approximately from 1,000 to 3,000, obtained by esterifying a polybasic acid (or an anhydride thereof) and a polyhydric alcohol. Commonly available unsaturated polyesters can be used.

Specific examples of the polybasic acid (or an anhydride thereof) which can be used as a raw material of the unsaturated polyester include, maleic anhydride, maleic acid, fumaric acid, itaconic acid, phthalic anhydride, orthophthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic anhydride, tetrahydroorthophthalic acid, methyltetrahydrophthalic anhydride, methyltetrahydro-orthophthalic acid, endomethylene tetrahydrophthalic anhydride, endomethylene tetrahydroorthophthalic acid, adipic acid, sebacic acid, HET acid, tetrabromophthalic anhydride, dimethyl 2,6- naphthalenedicarboxylate, dodecanoic acid, dicyclopentadiene maleic acid adduct and 1,4- cyclohexanedicarboxylic acid.

Specific examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, propylene glycol,

dipropylene glycol, neopentyl glycol, 1,4-cyclohexane- dimethanol, xylylene glycol, 1,3-butanediol, 1,4- butanediol, 2-methylpropanediol, pentaerythritol, bisphenol A, hydrogenated bisphenol A, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, glycerin monoallyl ether and pentaerythritol diallyl ether.

As a particular example, a low molecular weight polyethylene terephthalate resulting from the glycol decomposition of recycled polyethylene terephthalate and having a terminal hydroxyl group can be used.

In the esterification, polycondensation is performed in an inert gas stream at a temperature between 180°C and 220°C according to an ordinary method. The resulting unsaturated polyester having a molecular weight on the order of 1,000 to 3,000 can be used as it is in the present invention. Of course, the polyester may be subjected to some purification operation, if desired, before use.

The content and proportion of respective components (1) to (4) in the ordinary temperature curable resin composition of the present invention (I) are not particularly limited. These can be selected according to the viscosity required in view of workability at the time of molding the resin composition, the curing properties such as curing time and curing temperature, and various physical properties which the cured product after curing are required to have.

The ratio of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule to (2) the allyl monomer of a saturated and/or unsaturated polybasic acid in the present invention (I) is not particularly limited. The ratio is preferably, in terms of weight ratio between (1) and (2), (1): (2) =1: 9 to 9: 1, more preferably (1): (2) =2: 8 to 8: 2.

If the proportion of (1) is excessively low, the ordinary temperature curability of the resin composition

may lower extremely and this is not preferred, whereas if the proportion of (1) is too high, the cured product may be disadvantageously deteriorated in the heat resistance or physical properties such as strength.

The ratio of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule to (2) the allyl monomer of a saturated and/or unsaturated polybasic acid in the resin composition of the present invention (I) can be measured, for example, generally known gas chromatography or gel permeation chromatography.

The amount of (3) the acetoacetamide compound used in the present invention (I) is described below. The amount of (3) the acetoacetamide compound is not particularly limited. The preferred amount varies depending on the ratio of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule to (2) the allyl monomer of a saturated and/or unsaturated polybasic acid, the proportion of their total amounts occupying in the entire resin composition, and the physical properties such as structure and molecular weight of (1) and (2), however, this amount is generally from 0.01 to 5 parts by mass per 100 parts by mass as a total of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule and (2) the allyl monomer of a saturated and/or unsaturated polybasic acid contained in the ordinary temperature curable resin composition.

If (3) is less than 0.01 part by mass, its effect may be scarcely brought out and this is not preferred, whereas if (3) is used in excess of 5 parts by mass, the resin composition may be colored or stink or the ordinary temperature curability of the resin composition itself may deteriorate and this is not advantageous. The amount is more preferably from 0.05 to 2 parts by mass, still more preferably from 0.1 to 1 part by mass.

However, these numerical values vary depending on

the state and property of the resin composition as a whole and the amount is not limited thereto.

The amount of (4) the unsaturated polyester used in the present invention (I) is also not particularly limited. The ordinary temperature curable resin composition of the present invention (I) is resultant from further adding (4) an unsaturated polyester to the ordinary temperature curable resin composition and by this addition, the cured product can be increased in the strength. Accordingly, (4) may be used in any proportion as long as the ordinary temperature curability is maintained. Similarly to (3) the acetoacetamide compound described above, the preferred amount also varies depending on the state and property of the resin composition as a whole, however, this is generally from 5 to 500 parts by mass per 100 parts by mass as a total of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule and (2) the allyl monomer of a saturated and/or unsaturated polybasic acid contained in the ordinary temperature curable resin composition.

If (4) is less than 5 parts by mass, its effect may be scarcely brought out and this is not preferred, whereas if (4) is used in excess of 500 parts by mass, the viscosity may excessively increase depending on the state and property of the resin composition and this may disadvantageously cause failure in molding of the resin composition. The amount is more preferably from 5 to 200 parts by mass, still more preferably from 5 to 100 parts by mass.

The ordinary temperature curable resin composition of the present invention (I) can be used in combination with various conventionally known materials. Examples of the material which can be used in combination include an inorganic and/or organic reinforcing agent, a filler, a mold releasing agent, a defoaming agent, a coloring agent, a polymerization inhibitor, a wax, and an oil and

fat.

Specific examples of the inorganic and/or organic reinforcing agent include glass fiber, carbon fiber, aramid fiber, vinylon fiber and metal fiber.

Specific examples of the filler include calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, aluminum hydroxide, clay, talc, kaolin, kieselguhr, mica powder, glass fiber powder, powdered asbestos, silica gel and rock wool.

Specific examples of the mold releasing agent include waxes and stearic acid metal salts represented by zinc stearate.

Specific examples of the defoaming agent include silicon oils, polyvinyl ethers, acrylic acid ester copolymers and fluorine-containing compounds.

The polymerization inhibitor is not only added at the synthesis of the oligo (meth) acrylate, the synthesis of the unsaturated polyester or the synthesis of the allyl monomer but also may be added so as to prevent the resin composition of the present invention (I) and the present invention (II) from alteration before use or to adjust the time until gelling at the molding. Specific examples of the polymerization inhibitor include para- benzoquinone, methoxyphenol, naphthoquinone, phenanthraquinone, toluquinone, 2,5-diacetoxy-p- benzoquinone, 2,5-dicaproxy-p-benzoquinone, 2,5-acyloxy- p-benzoquinone, hydroquinone, p-tert-butylcatechol, 2,5- di-tert-butylhydroquinone, mono-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, di-tert-butyl-para-cresol hydroquinone monomethyl ether, a-naphthol, copper naphthenate, acetoamidine acetate, acetoamidine sulfate, phenylhydrazine hydrochloride, hydrazine hydrochloride, trimethylbenzylammonium chloride, laurylpyridinium chloride, cetyltrimethylammonium chloride, phenyltrimethylammonium chloride, trimethylbenzylammonium oxalate, di (trimethylbenzylammonium) oxalate, trimethylbenzylammonium maleate, trimethylbenzylammonium

tartrate, trimethylbenzylammonium glycolate, phenyl-ß- naphthylamine, para-benzylaminophenol, di-p-naphthyl- para-phenyldiamine, dinitrobenzene, trinitrotoluene, picric acid, cyclohexanone oxime, pyrogallol, tannic acid, resorcin, triethylamine hydrochloride, dimethylaniline hydrochloride and dibutylamine hydrochloride.

The present invention (II) is described below. The present invention (II) is a method for curing the resin composition of the present invention (I).

The curing method of the resin composition, as the present invention (II), is not particularly limited.

Curing may be attained by a conventionally known curing method for resin compositions. The resin composition can be cured if a radical can be generated by some means such as light or heat and, needless to say, use of a curing agent (radical generator). In particular, curing at an ordinary temperature using a curing agent is particularly effective because this method is suitable for the properties of the resin composition of the present invention (I).

The curing agent which can be used in the present invention (II) at the time of curing the resin composition of the present invention (I) is not particularly limited and any may be used as long as it has an ability of generating a radical necessary for curing conventionally known radical curable resin compositions. In particular, a peroxide is preferred.

Specific examples of the peroxide which can be used include methyl ethyl ketone peroxide, cyclohexanone peroxide, methylacetoacetate peroxide, acetylacetone peroxide, bis (l-hydroxycyclohexyl) peroxide, 1, 1-bis (tert- butylperoxy) -3,3, 5-trimethylcyclohexane, cumene hydroperoxide, dicumyl peroxide, benzoyl peroxide, bis (4- tert-butylcyclohexyl) peroxy dicarbonate, tert-butylperoxy benzoate, tert-butylperoxy pivalate, tert-butylperoxy-2-

ethyl hexanoate and lauroyl peroxide. These curing agents may be used individually or in combination.

The curing agent for use in the curing method of resin composition, which is the present invention (II), may be only the above-described peroxide but a curing accelerator may be used in combination. In this case, the combination of the peroxide and the curing accelerate is sometimes referred to as a"composite curing agent".

Examples of the curing accelerator which can be used include at least one compound selected from the group consisting of a cobalt salt, a copper salt, a manganese salt and a calcium salt of organic acid compound, at least one compound selected from the group consisting of a sulfonic acid compound and a salt thereof, and at least one compound selected from tertiary amines. Specific examples thereof include cobalt naphthenate, copper naphthenate, manganese naphthenate, calcium naphthenate, cobalt stearate, copper stearate, cobalt octoate, N, N- dimethylaniline, N, N-diethylaniline, N, N-dimethyl-para- toluidine, pyridine, phenylmorpholine, diphenyl disulfide, para-toluenesulfonic acid and sodium dodecylsulfonate. These curing accelerators can be used individually or in combination.

In the case of a composite curing agent, the combination of the peroxide and the curing accelerator greatly affects the curability. Preferred examples of the combination in the composite curing agent suitable for the present invention include the following.

However, the present invention is not limited to these combinations.

Methyl ethyl ketone peroxide-cobalt naphthenate Benzoyl peroxide-N, N-dimethylaniline Benzoyl peroxide-N, N-dimethyl-para-toluidine In addition to the composite curing agent, an acceleration aid for accelerating the curing may also be used. The acceleration aid means a tertiary component added in addition to the peroxide and the curing

accelerator. Accordingly, use of a curing accelerator as the acceleration aid is also included.

Specific examples of the acceleration aid include acetylacetone, dimedone, dibenzoylmethane, acetylcyclopentane, acetoacetic acid ester and acetylbutyrolactone.

In the curing method of resin composition, which is the present invention (II), the amount of the curing agent used is not particularly limited and the preferred range varies depending on the state and property of the resin composition as a whole or the state and property of the curing agent itself, but this range is generally from 0.01 to 10 parts by mass per 100 parts by mass as a total of (1) the oligo (meth) acrylate having one or more (meth) acryloyl group within one molecule and (2) the allyl monomer of a saturated and/or unsaturated polybasic acid contained in the ordinary temperature curable resin composition. If the curing agent is less than 0.01 part by mass, curing may be seriously retarded and this is not preferred, whereas if the curing agent is used in excess of 10 parts by mass, the curing product may be disadvantageously deteriorated in the physical properties. The amount used is preferably from 0.05 to 8 parts by mass, more preferably from 0.1 to 5 parts by mass.

The amount used of the composite curing agent where a peroxide is used as the curing agent, and this is combined with a curing accelerator, is also not particularly limited. Similarly to the above-described curing agent, the preferred amount varies depending on the state and property of the resin composition as a whole or the state and property of the composite curing agent itself, but this is generally from 0.001 to 10 parts by mass per 100 parts by mass as a total of (1) the oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule and (2) the allyl monomer of a saturated and/or unsaturated polybasic acid contained in

the ordinary temperature curable resin composition. If the composite curing agent is less than 0.001 part by mass, curing may be seriously retarded and this is not preferred, whereas if the composite curing agent is used in excess of 10 parts by mass, the curing product may be disadvantageously deteriorated in physical properties.

The amount used is preferably from 0.01 to 8 parts by mass, more preferably from 0.05 to 5 parts by mass.

In the curing method of resin composition, which is the present invention (II), the molding method is not particularly limited but preferred are hand lay-up molding and spray-up molding. The hand lay-up molding is a molding method of applying the resin composition to a mold using a roller and the spray-up molding is a method of atomizing the resin composition using a compressed air and spraying it on a mold. These are described in detail in Polyester Jushi Handbook (Handbook of Polyester Resin), 1st ed. , 1st imp. , pp. 507-539 (June 30,1988)).

The present invention (III) is described below. The present invention (III) is a cured product of the resin composition of the present invention (I).

The cured product of the present invention (III) may have any state and property as long as it is obtained by curing the resin composition of the present invention (I). The curing method is also not particularly limited, however, the curing product is preferably obtained by curing the resin composition of the present invention (I) at an ordinary temperature by making use of its ordinary temperature curability, using a curing agent (including a composite curing agent) used in the curing method of the present invention (II). An excess active energy such as heat or ultraviolet ray needs not be applied at the curing and the curing can be performed under mild conditions. As a result, a cured product particularly excellent in the physical properties such as color tone can be obtained.

Also, the physical properties of the cured product

can be advantageously controlled with ease by changing the state and property or the blending ratio of each component used in the resin composition of the present invention (I) as a starting material.

The present invention is further illustrated below by referring to Examples, however, the present invention is not limited thereto.

Respective physical properties were measured as follows.

1. Viscosity, Acid Value, Color Number and Specific Gravity of Resin Composition The viscosity, acid value, color number and specific gravity of the resin composition were measured according to JIS K 6901: 1999.

2. Tensile Strength, Tensile Modulus The tensile strength and tensile modulus of the cured product obtained by a casting method were measured according to JIS K 7113: 1995. The tensile strength and tensile modulus of FRP obtained by a lamination method were measured according to JIS K 7054: 1995.

3. Bending Strength and Bending Modulus The bending strength and bending modulus of the cured product obtained by a casting method were measured according to JIS K 7203: 1995. The bending strength and bending modulus of the cured product obtained by a lamination method were measured according to JIS K 7055: 1995.

Production Example 1: Synthesis of Oligo (meth) acrylate (hereinafter referred to as"Polyester-Methacrylate (A)) Into a 1 liter separable flask with a stirrer, a cooling condenser, a thermometer and a gas inlet tube, 260 g of 2-hydroxyethyl methacrylate, 135 g of phthalic anhydride, 0.8 g of triphenylantimony and 0.4 g of methoxyphenol were charged and reacted at 180 to 185°C for 1 hour and 30 minutes in an air stream. As a result, the acid value became 35 KOH-mg/g and therefore, the

reaction was stopped. The distilled amount was about 38 ml. The obtained Polyester-Methacrylate (A) had a Hazen color number of 350 and a viscosity of 690 mPa s.

Production Example 2: Synthesis of Unsaturated Polyester (B) Into a 1 liter four-neck flask with a stirrer, a cooling condenser, a thermometer and a gas inlet tube, 160 g of propylene glycol, 89 g of phthalic anhydride and 137 g of maleic anhydride were charged and esterified at 180 to 210°C in a nitrogen gas stream. When the acid value became 41, the condenser was exchanged with a vacuum cooling-type condenser and the reaction was performed at 250°C for 1 hour under reduced pressure of 2 to 3 kPaA. When the acid value became 21 KOH-mg/g, the reaction was stopped. After adding 0.06 g of hydroquinone, the reactant was injected into a metal vat and solidified to obtain pale yellow Unsaturated Polyester (B).

Production Example 3: Synthesis of Vinyl Ester (C) Into a 1 liter separable flask with a stirrer, a cooling condenser and a thermometer, 360 g of Epicote (registered trademark) 827 (produced by Shell) as an epoxy resin composition, 137 g of acrylic acid, 1.5 g of triphenylphosphine, 0.25 g of phosphorous acid and 0.5 g of methoxyphenol were charged and reacted at 130 to 135°C for 3 hours in air. As a result, the acid value became 10 KOH-mg/g and therefore, the reaction was stopped.

Vinyl Ester (C) was obtained as a pale yellow syrup.

Production Example 4: Synthesis of Oligo (meth) acrylate (hereinafter referred to as"Urethane-Acrylate (D)") Into a 1 liter separable flask with a stirrer, a reflux condenser, a dropping funnel and a thermometer, 188 g of xylylene diisocyanate, 200 g of diallyl isophthalate, 0.4 g of dibutyltin dilaurate and 0.04 g of phenothiazine were charged and while keeping it at 70 to

75°C, 232 g of 2-hydroxyethyl acrylate was added dropwise in 30 minutes. After the dropwise addition, the reaction was performed at the same temperature for 3 hours and as a result of infrared absorption, it was confirmed that the absorption of isocyanate group was completely quenched. A pale red-violet viscous diallyl isophthalate solution of Urethane-Acrylate (D) was obtained.

Production Example 5: Synthesis of Unsaturated Polyester (E) Into a 2 liter separable flask with a stirrer, a cooling condenser, a gas inlet tube and a thermometer, 116 g of maleic acid and 250 g of dicyclopentadiene were charged and reacted at 180 to 190° for 2 hours.

Thereafter, the condenser was exchanged with a fractionating condenser, the temperature was lowered to 130°C and, after adding 325 g of ethylene glycol and 490 g of maleic anhydride, esterification was performed at 200 to 205°C for 8 hours in a nitrogen gas stream. As a result, the acid value became 25 KOH-mg/g and therefore, the reaction was stopped. After adding 0.1 g of hydroquinone, the reactant was injected and solidified.

Unsaturated Polyester (E) was obtained as a red-tinted brown solid which was slightly soft at room temperature.

Production Example 6: Synthesis of Polyester Resin Composition (F) Into a 1 liter separable flask with a stirrer, a cooling condenser, a gas inlet tube, a thermometer and a dropping funnel, 192 g of recycled polyethylene terephthalate (hereinafter simply referred as"R-PET") flakes and 0.4 g of dibutyltin dilaurate was charged.

After melting R-PET at near 270°C for about 20 minutes, 76 g of propylene glycol and 26 g of glycerin monoallyl ether were added dropwise over 15 minutes and R-PET was decomposed to a molecular weight of 800 or less at 220 to 230°C for 3 hours. Thereafter, the condenser was exchanged by a fractionating condenser and 98 g of maleic acid was added at 160°C. Esterification was allowed to

proceed at 200 to 205°C in a nitrogen gas stream and then, condensation was allowed to proceed for 30 minutes under reduced pressure of 10 to 20 kPaA. Polyester Resin Composition (F) having a final acid value of 27 KOH-mg/g was obtained as a brown transparent solid.

Production Example 7: Synthesis of Unsaturated Polyester (G) Into a 1 liter four-neck flask with a stirrer, a cooling condenser, a thermometer and a gas inlet tube, 799 g of propylene glycol, 831 g of isophthalic acid and 490 g of maleic anhydride were charged and esterified at 180 to 210°C in a nitrogen gas stream. When the acid value became 41, the condenser was exchanged by a vacuum cooling-type condenser and the reaction was performed at 250°C for 1 hour under reduced pressure of 2 to 3 kPaA.

When the acid value became 21 KOH-mg/g, the reaction was stopped. After adding 0.06 g of hydroquinone, the reactant was injected into a metal vat and solidified to obtain pale yellow Unsaturated Polyester (G).

Production Example 8: Synthesis of Oligo (meth) acrylate (hereinafter referred to as"Polyester-Acrylate (H)") Into a 1 liter glass-made autoclave, 144 g of acrylic acid, 166 g of propylene oxide, 89 g of phthalic anhydride, 1.2 g of dimethylbenzylamine, 0.44 g of phenothiazine, 0.4 g of triphenylantimony and 0.4 g of antimony trioxide were charged and reacted at a maximum temperature of 131°C and a maximum pressure of 0.5 MPaG for 2 hours.

Subsequently, the obtained reaction mixture was transferred to a 1 liter separable flask with a stirrer, a fractionating condenser, a thermometer and a gas inlet tube and reacted at 179 to 183°C for 80 minutes in an air stream. Then, pale red-brown Polyester-Acrylate (H) having a viscosity of about 500 means was obtained.

Example 1 The resins and compounds except for the curing

agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 25°C, a composite curing agent (hereinafter simply referred to as a"curing agent") comprising PERMEC N (produced by NOF, 35-45 mass% methyl ethyl ketone peroxide dimethyl phthalate solution) and cobalt naphthenate (produced by Wako Pure Chemical Industries, Ltd. , cobalt: 6 mass%) was added as a curing agent and mixed with stirring. As a result, heat was gradually generated and after nearly 5 minutes, exothermic curing abruptly occurred. The maximum exothermic temperature reached 129°C. After the heat generation was finished, a solid having no flowability was obtained.

Table 1 Example Example Example Example Example Example Example Example Example 1 2 3 4 5 6 7 8 9 Component (1) Polyester-Acrylate (A) 0 50 40 0 0 0 50 40 10 Vinyl Ester (C) 0 0 0 40 0 0 0 0 0 Urethane-Acrylate (D) 0 0 0 0 45 0 0 0 0 Polyester-Acrylate (H) 50 0 0 0 0 0 0 0 20 Dipentaerythritol 0 0 0 0 0 30 0 0 0 hexaacrylate Component (2) Diallyl terephthalate 50 50 40 50 0 50 30 40 50 Diallyl isophthalate 0 0 0 0 25 0 0 0 0 Triallyl isocyanurate 0 0 0 0 10 0 0 0 0 Component (3) Acetoacetylpyrrolidine 0.30 0.30 0.30 0.20 0 0.20 1.00 1.00 1.00 N, N-Dimethylacetoacetamide 0 0 0 0 1. 00 0 0 0 0 Component (4) Unsaturated Polyester (B) 0 0 20 10 0 0 0 0 0 Unsaturated Polyester (E) 0 0 0 0 20 0 0 0 0 Unsaturated Polyester (F) 0 0 0 0 0 26 0 0 0 Unsaturated Polyester (G) 0 0 0 0 0 0 20 20 20 Accelerator Cobalt naphthenate 0. 50 0.50 0.50 0.50 0.30 0.70 1.00 1.00 0.50 Curing agent PERMEC N 1. 00 1.00 1.50 1.20 1.50 1.50 2.00 2.00 1.00 Polymerization p-tert-butylcatechol 0. 10 0.26 0.10 Inhibitor In the Table, the numerical values are values showing the proportion ot each component<BR> in the whole composition in terms of weight ratio.

Example 2 The resins and compounds except for the curing agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 25°C, the curing agent was added and mixed with stirring. As a result, heat was gradually generated and after nearly 2 minutes, exothermic curing abruptly occurred. The maximum exothermic temperature reached 92°C. After the heat generation was finished, a solid having no flowability was obtained.

Example 3 The resin compositions and compounds except for the curing agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 15°C, the curing agent was added and mixed with stirring. As a result, gelling occurred in 12 minutes and heat was abruptly generated. The maximum exothermic temperature reached 163°C. The Barcol hardness of the cast-molded curable resin composition was 46.

Example 4 The resin compositions and compounds except for the curing agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 15°C, the curing agent was added and mixed with stirring. As a result, heat was gradually generated and after nearly 5 minutes, exothermic curing abruptly occurred. The maximum exothermic temperature reached 159°C. The Barcol hardness of the cast-molded curable resin composition was from 40 to 41.

Example 5 The resin compositions and compounds except for the curing agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 15°C, the curing agent was added and mixed with stirring. As a result, gelling occurred in 47 minutes and thereafter, heat was continuously generated to cause curing. The maximum exothermic temperature reached 134°C. The Barcol

hardness of the cured product obtained by cast-molding and then postcured at 80°C for 30 minutes was 42.

Example 6 A commercially available dipentaerythritol hexaacrylate (produced by Nippon Kayaku Co. , Ltd. ) was used for the oligo (meth) acrylate.

The resin compositions and compounds except for the curing agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 15°C, the curing agent was added and mixed with stirring. As a result, gelling occurred in 12 minutes and thereafter, heat was abruptly generated. The maximum temperature reached 169°C.

Example 7 Polyester-Methacrylate (A) was used for the oligo (meth) acrylate and Unsaturated Polyester (G) was used for the unsaturated polyester.

The resin compositions and compounds except for the curing agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 25°C, the curing agent and p-tert-butylcatechol for adjusting the polymerization time were added and mixed with stirring.

As a result, gelling occurred in 18 minutes and thereafter, heat was continuously generated to cause curing. The maximum exothermic temperature reached 100°C. The composition was cast-molded and the cured product was completely cooled and then postcured at 120°C for 2 hours. The physical properties of the cured product are shown in Table 2.

Table 2 Unit Example Example Example 7 8 9 Resin Appearance brown brown brown Composition liquid liquid liquid Viscosity mPa-s 591 367 400 Color number 200 200 80 Specific gravity g/ml 1. 185 1.182 1.204 Acid value KOH-mg/g 28 24 28 Water content mass% <0.1 <0.1 <0.1 Refractive index 1. 522 1. 520- Gelling time min 26 18 25 Minimum curing time min 37 26 33 Maximum temperature °C 108 97 158 reached Cured Bending strength MPa 115 89 96 Product, Bending modulus GPa 4.0 3.3 2.6 cast-molded Barcol hardness 43 37 32 plate Heat deformation °C 84 85 53 temperature Shrinkage percentage % 8 8 8 Water absorption1) mass% 0.2-0. 4 0.2-0. 4 0.2-0. 4 Cured Bending strength MPa 162 199 192 Product, Bending modulus GPa 8. 44 7.80 8.21 laminated Charpy impact kJ/m 64 75 74 plate strength

1) Increase of weight after dipping in pure water at 25°C for 24 hours.

Example 8 Polyester-Methacrylate (A) was used for the oligo (meth) acrylate and Unsaturated Polyester (G) was used for the unsaturated polyester.

The resin compositions and compounds except for the curing agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 25°C, the curing agent and p-tert-butylcatechol for adjusting the polymerization time were added and mixed with stirring.

As a result, gelling occurred in 18 minutes and thereafter, heat was continuously generated to cause curing. The maximum exothermic temperature reached 100°C. The composition was cast-molded and the cured product was completely cooled and then postcured at 120°C for 2 hours. The physical properties of the cured product are shown in Table 2.

Example 9

Polyester-Methacrylate (A) and Polyester-Acrylate (H) were used in combination for the oligo (meth) acrylate and Unsaturated Polyester (G) was used for the unsaturated polyester.

The resin compositions and compounds except for the curing agent, shown in Table 1, were thoroughly mixed and after adjusting the resin temperature to 25°C, the curing agent and p-tert-butylcatechol for adjusting the polymerization time were added and mixed with stirring.

As a result, gelling occurred in 31 minutes and thereafter, heat was continuously generated to cause curing. The maximum exothermic temperature reached 100°C. The composition was cast-molded and the cured product was completely cooled and then postcured at 120°C for 2 hours. The physical properties of the cured product are shown in Table 2.

Comparative Example 1 Unsaturated Polyester (G) was used for the unsaturated polyester. The resin compositions and compounds except for the curing agent, shown in Table 3, were thoroughly mixed and after adjusting the resin temperature to 25°C, the curing agent was added and mixed with stirring. The mixture was allowed to stand for 24 hours, however, heat was scarcely generated and curing was not attained.

Table 3 Comparative Comparative Example 1 Example 2 Component (1) Polyester-Acrylate (A) 0 0 Vinyl Ester (C) 0 0 Urethane-Acrylate (D) 0 0 Polyester-Acrylate (H) 0 40 Dipentaerythritol 0 0 hexaacrylate Component (2) Diallyl terephthalate 50 40 Diallyl isophthalate 0 0 Triallyl isocyanurate 0 0 Component (3) Acetoacetylpyrrolidine 0. 50 0. 00 N, N-Dimethylacetoacetamide 0 0 Component (4) Unsaturated Polyester (B) 0 0 Unsaturated Polyester (E) 0 0 Unsaturated Polyester (F) 0 0 Unsaturated Polyester (G) 50 20 Accelerator Cobalt naphthenate 0. 50 0. 50 Curing agent PERMEC N 1. 00 1. 00 Polymerization p-tert-Butylcatechol 0 0 inhibitor

In the Table, the numerical values are values showing the proportion of each component in the whole composition in terms of weight ratio.

Comparative Example 2 Polyester-Acrylate (H) was used for the oligo (meth) acrylate and Unsaturated Polyester (G) was used for the unsaturated polyester.

The resin compositions and compounds except for the curing agent, shown in Table 3, were thoroughly mixed and after adjusting the resin temperature to 25°C, the curing agent was added and mixed with stirring. The mixture was allowed to stand for 24 hours, however, heat was scarcely generated and curing was not attained.

Industrial Applicability As described above, it is apparent that the resin composition of the present invention comprising (1) an oligo (meth) acrylate having one or more (meth) acryloyl groups within one molecule, (2) an allyl monomer of a saturated and/or unsaturated polybasic acid and (3) an acetoacetamide compound has ordinary temperature curability equal to that of conventional general-purpose radical curable resin compositions. Moreover, styrene

need not be used for adjusting the viscosity which is an important factor for providing satisfactory moldability.

Thus, a"non-styrene type resin composition"most keenly demanded as the general-purpose resin composition can be provided.

Furthermore, for the curing of the resin composition of the present invention, a conventionally known general method can be used. Also from this point, it is apparent that the resin composition of the present invention can be used for various uses.