JPH0748394A - (meth)acrylic acid ester, production thereof, curable resin composition using the same and cured product thereof - Google Patents

Abstract

PURPOSE:To obtain a new (meth)acrylic acid ester, excellent in transparency, having characteristics such as a high refractive index and flame retardancy and useful as a material for forming various protective films for films or moldings, etc., a coating material for various optical instruments and an adhesive for various substrates, etc. CONSTITUTION:This compound is expressed by formula I (R is H or CH3). The compound expressed by formula I is obtained by reacting a compound expressed by formula II with an acrylic or a methacrylic acid ester in the presence of 1-5mol% esterification catalyst (e.g. an acidic catalyst such as sulfuric acid or p-toluenesulfonic acid).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel (meth) acrylic acid ester, a method for producing the same, a curable resin composition using the same, and a cured product thereof. More specifically, the novel (meth) acrylic acid ester of the present invention, a curable resin composition containing the same is easily polymerized by heating or ultraviolet irradiation in the presence of a radical polymerization initiator or a cationic polymerization initiator, The cured product has excellent transparency and a high refractive index,
It has properties such as flame retardancy and can be widely used as materials for forming various protective films such as films and molded products, coating materials for various optical devices, and adhesive materials for various base materials. Further, it can be favorably used as a film, a sheet, a lens, a glass substitute, or the like.

[0002]

2. Description of the Related Art A curable resin or a curable resin composition is
Since it is easily cured by irradiation with radiation such as heat rays, ultraviolet rays, and electron rays, it is widely used, for example, as a protective film forming material for various plastic molded products, UV curable printing ink, and adhesive. Further, in recent years, as a material replacing an inorganic optical lens, a lens made of a transparent synthetic resin has excellent lightness, impact resistance and molding processability, and thus the field of application is expanding. A resin having a high refractive index is desired to reduce the weight of the lens.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cured product having high refractivity and flame retardancy which does not require complicated operations during production and is colorless and excellent in transparency. is there.

[0004]

DISCLOSURE OF THE INVENTION As a result of intensive studies in view of the present situation, the present inventors have found that a resin composition containing a novel (meth) acrylic acid ester as an essential component and a cured product thereof have the above problems. The inventors have found that the points are solved and completed the present invention. That is, the present invention provides (1) a (meth) acrylic acid ester represented by the general formula [1]

[Chemical 3] (2) The method for producing a (meth) acrylic acid ester according to claim 1, wherein the compound represented by the general formula [2] is reacted with (meth) acrylic acid.

[Chemical 4] (3) A curable resin composition containing the (meth) acrylic acid ester according to claim 1. (4) A cured product of the curable resin composition according to claim 3. It is about. The present invention described above will be described in more detail below. The (meth) acrylic acid ester represented by the formula [1] of the present invention is used for various protective films such as films, sheets, lenses and molded products by taking advantage of its transparency, high refractivity and flame retardancy. Suitable as a component of UV curable resin composition, which can be widely used for forming materials, adhesives, etc., especially for optical applications such as lens manufacturing such as Fresnel lenses and eyeglass lenses, and adhesion of optical lenses and optical parts, coating, etc. Available. Further, the (meth) acrylic acid ester of the present invention is easily hydrolyzed by an alkali to become a water-soluble curable resin, which is used as a curable resin material for applications requiring water solubility and as a polymer raw material. You can also

The (meth) acrylic acid ester of the present invention is
It can be obtained by esterifying the compound represented by the general formula [2] with (meth) acrylic acid. In more detail, the amount of (meth) acrylic acid used is usually a stoichiometric ratio or higher with respect to the compound represented by the general formula [2], and generally the carboxylic acid to alcohol is used. The molar ratio is 1.0 to 2.0, but preferably 1.1 to 1.5. The reaction uses an esterification catalyst, and the produced water is promoted by distilling off. Such an esterification catalyst is an acidic catalyst such as sulfuric acid or P-toluenesulfonic acid, and the amount thereof is 0.1 to 10 mol% with respect to acrylic acid or methacrylic acid, preferably 1
~ 5 mol% is used. It is advantageous to use an azeotropic solvent to distill off the water generated by the reaction, and such an azeotropic solvent has a boiling point of 60 to 130 ° C. and can be used if it is easily separated from water. Suitable are aliphatic hydrocarbons such as n-hexane and n-heptane, aromatic hydrocarbons such as benzene and toluene, and alicyclic hydrocarbons such as cyclohexane. The amount used is usually 5 to 5% of the reaction mixture.
It is 70% by weight. The reaction temperature may be in the range of 60 to 130 ° C., but from the viewpoint of shortening the reaction time and preventing polymerization, it is 75 to
Advantageously, it is carried out at 120 ° C. A polymerization inhibitor is usually added to (meth) acrylic acid, but a polymerization inhibitor may be added again during the reaction. Examples of such a polymerization inhibitor include hydroquinone, P-methoxyphenol, 2,4-dimethyl-6-t-butylphenol, 3-hydroxythiophenol, α-nitroso β-naphthol, P-benzoquinone, 2,5-dihydroxy-P-quinone and phenothiazine. Nitrosodiphenylamine, copper salts and the like. The amount used is usually 0.01 to 1% by weight with respect to the reaction mixture. The (meth) acrylic acid ester of the present invention is used for industrial purposes by washing with water or an aqueous alkali solution, etc., if necessary, or by separating from the solvent by a method such as vacuum distillation.

(Meth) represented by the general formula [1] of the present invention
The acrylic acid ester can be cured by irradiating it with an electron beam, but is usually used as a curable resin composition that is cured by ultraviolet rays and / or heat by adding a polymerization initiator. The curable resin composition of the present invention can be prepared by dissolving the (meth) acrylic acid ester represented by the general formula [1] and a photopolymerization initiator or / and a thermal polymerization initiator. A photopolymerization initiator is used in the case of curing with ultraviolet rays. As the photopolymerization initiator,
Although any known photopolymerization initiator can be used, it is required to have good storage stability after compounding. Examples of such a photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone, benzyl dimethyl ketal, 2-hydroxy-2-methylpropiophenone, benzophenone, 4-isopropyl-2-hydroxy-2.
-Photo radical polymerization initiators such as methylpropiophenone, and photocationic polymerization initiators such as diphenyliodonium hexafluoroantimonate, triphenylsulfonium hexafluorophosphate, and triphenylsulfonium hexafluoroantimonate. . Further, in the case of curing with infrared rays or heat, a thermal polymerization initiator is used. As the thermal polymerization initiator, any known thermal polymerization initiator can be used, but an organic peroxide is generally used. Examples of the organic peroxide include methyl ethyl ketone peroxide, bis-3,3,5-
Trimethylhexanoyl peroxide, lauroyl peroxide, benzoyl peroxide, cumene hydroperoxide, dicumyl peroxide, di-
Examples thereof include t-butyl peroxide, 3,3,5-trimethylcyclohexanone peroxide, 2,2-di-t-butylperoxybutane, and diisopropylperoxydicarbonate. These polymerization initiators can be used alone or in combination of two or more at an arbitrary ratio. The amount used is preferably 0.1 to 10 wt% of the curable resin composition of the present invention, particularly 0.5 to 7 wt%.
Is preferred. The novel (meth) acrylate (1) of the present invention gives a cured product by a known curing method. For example, the curable resin composition of the present invention containing the (meth) acrylic acid ester represented by the general formula [1] of the present invention and a photopolymerization initiator is irradiated with ultraviolet rays or visible rays to give a cured product. Further, the curable resin composition of the present invention containing the (meth) acrylic acid ester represented by the general formula [1] of the present invention and a thermal polymerization initiator may be irradiated with infrared rays or heated to give a cured product. it can. Each of the obtained cured products has a higher refractive index than that obtained from the generally known (meth) acrylate. In addition to the polymerization initiator, the novel (meth) acrylic acid ester of the present invention includes non-reactive polymers, oligomers, monomers, photopolymerization accelerators, polymerization inhibitors, thickeners, leveling agents, fluidity improvers, and deodorants. Foaming agent, matting agent, thixotropic agent, plasticizer, solvent, extender pigment,
Auxiliaries such as colorants such as pigments and dyes can be used in combination. Further, the curable resin composition of the present invention can also be emulsified and used.

[0007]

EXAMPLES The present invention will be described in more detail below with reference to synthesis examples and examples, but the present invention is not limited to these examples. The curable composition and various properties of the cured product were evaluated by the following methods. (Viscosity) The viscosity at 25 ° C. was measured using an E-type viscometer. (Refractive Index) The refractive index at 20 ° C. was measured using an Abbe refractometer. Examples of synthesis Example 1 2 equipped with a stirrer, thermometer, water separator with condenser
In the L reactor, 3,4,5,6-dibenzo-1,2-oxaphosphane-2-oxide (manufactured by Sanko Chemical Co., product name S
AKO-HCA) was charged at 432 g and gradually increased to 120
After heating to 0 ° C and melting, 72 g of paraformaldehyde was gradually charged with stirring and the reaction was carried out at a temperature of 120 to 125 ° C for 3 hours. After confirming that the reaction solution was free from 3,4,5,6-dibenzo-1,2-oxaphosphane-2-oxide by liquid chromatography, the reaction solution was cooled to room temperature and charged with 500 g of 20% caustic soda to uniformly dissolve it. . Then, 15% hydrochloric acid is stirred to gradually add crystals until it becomes slightly acidic. Then, the crystals were filtered, washed with water and then filtered and dried to obtain 380 g of a white crystal having a melting point of 165 ° C. The main peaks detected by measuring the mass spectrum of this product are shown below. m / z 246 (parent ion) m / z 216 m / z 215 m / z 168 m / z 139 The results of 13 C-nuclear magnetic resonance (NMR) measurement of this product are shown below. In the measurement, tetramethylsilane was used as a reference substance and deuterated chloroform was used as a solvent, and the measurement was carried out by the proton decoupling method.

[0008] From these results, it was found that the obtained crystal product was a compound having the structure represented by the formula [2].

Then, 369 g of the obtained crystal product, 216 g of acrylic acid, 600 g of toluene, 2.2 of metoquinone.
g, 21.6 g of PTS were charged into a 1 L reactor equipped with a stirrer, thermometer, and water separator with condenser, and 105-1
The dehydration condensation reaction was carried out at 10 ° C. for 13 hours, the obtained reaction solution was washed twice with a 10% aqueous sodium carbonate solution and once with a 20% saline solution, and then toluene was distilled under reduced pressure to obtain 303 g of a slightly yellow liquid. It was The viscosity of this product at 40 ℃ is 63
The refractive index at 00 CPS and 20 ° C. was 1.6145. The main peaks detected by measuring the mass spectrum of this product are shown below. m / z 300 (parent ion) m / z 215 m / z 168 m / z 139 Further, the results of ¹³ C-nuclear magnetic resonance (NMR) measurement of this product are shown below. In the measurement, tetramethylsilane was used as a reference substance and deuterated chloroform was used as a solvent, and the measurement was carried out by the proton decoupling method.

[0010] From these results, it was found that the obtained viscous liquid was an acrylate ester having the following structure.

[0011]

[Chemical 5]

Example 2 1 equipped with a stirrer, thermometer, water separator with condenser
The compound 246 of the formula [2] obtained in Example 1 was placed in an L reactor.
g, 172 g of methacrylic acid, 500 g of toluene, 1.7 g of methoquinone, and 17 g of paratoluenesulfonic acid were charged, and a dehydration condensation reaction was carried out at 90 to 95 ° C. for 10 hours. 20
After washing three times with a% saline solution, toluene was distilled under reduced pressure to obtain 262 g of a slightly yellow liquid. This product has a viscosity of 5200 CPS at 40 ° C and a refractive index of 1.607 at 20 ° C.
It was 8. The main peaks detected by measuring the mass spectrum of this product are shown below. m / z 314 (parent ion) m / z 215 m / z 192 m / z 168 m / z 139 Further, the results of ¹³ C-nuclear magnetic resonance (NMR) measurement of this product are shown below. In the measurement, tetramethylsilane was used as a reference substance and deuterated chloroform was used as a solvent, and the measurement was carried out by the proton decoupling method.

[0013] From these results, it was found that the obtained viscous liquid was a methacrylic acid ester having the following structure.

[0014]

[Chemical 6]

Example of Cured Product Example 3 3 wt% of hydroxycyclohexyl phenyl ketone as a photo-radical polymerization initiator was added to the (meth) acrylic acid esters obtained in Examples 1 and 2 (Ciba Geigy, product name Irgacure 184). Was added to obtain a curable resin composition of the present invention. This curable resin composition was applied on a glass plate in a thickness of about 50 μm, and then irradiated with ultraviolet rays of 150 mj / cm ² with a high pressure mercury lamp in a nitrogen atmosphere to obtain a cured product. The refractive index of the obtained cured product is shown in Table 1.

Example 4 3 wt% of t-butylperoxy-2-ethylhexanoate (manufactured by Kayaku Akzo Co., product name Kayaester O) as a peroxide was added to the (meth) acrylic acid ester obtained in Example 1. -50) was added to obtain a curable resin composition of the present invention. This curable resin composition was applied on a glass plate in a thickness of about 50 μm, and then heated in a dryer at 130 ° C. for 10 minutes to obtain a cured product. The refractive index of the obtained cured product is first
Shown in the table.

Example 5 To the (meth) acrylic acid ester obtained in Example 2, 2 wt% of a diphenyl sulfide derivative (manufactured by Asahi Denka Co., Ltd., product name SP-170) was added as a cationic photopolymerization initiator,
A curable resin composition of the present invention was obtained. After applying this curable resin composition on a glass plate in a thickness of about 50 microns,
A cured product was obtained by irradiating 150 mj / cm ² of ultraviolet rays in the air with a high pressure mercury lamp. The refractive index of the obtained cured product is shown in Table 1.

Comparative Example The well-known conventionally known (meth) acrylic acid ester has a refractive index at 20 ° C. and cured products thereof prepared by the same method as in Examples 3 to 5 have a refractive index of 1%. Shown in the table.

[0019]

[Table 1] Table 1 Refractive index of a cured product obtained by the method shown in the following Examples Example 3 Example 4 Example 5 Actual compound of Example 1 1.6175 Example of compound 1 of Example 1 1.6178 Example Implementation Compound of Example 2 1.6172 Ratio R-128H * 1 1.5308 Comparison R-561 * 2 1.5498 Example R-551 * 3 1.5415

* 1 KAYARAD R-128H 2-hydroxy-3-phenoxypropyl acrylate * 2 KAYARAD R-561 2-phenoxyethyl acrylate * 3 KAYARAD R-551 Bisphenol A polyethylene glycol ether diacrylate

[0021]

EFFECT OF THE INVENTION A (meth) acrylate which can be easily cured by a radical and cation curing system and has a higher refractive index than the conventionally well-known (meth) acrylate and gives a flame-retardant cured product is obtained. It was

Claims (4)

[Claims] 1. A general formula [1]: (However, R is H or CH _3. ) A (meth) acrylic acid ester represented by. 2. A compound represented by the general formula [2] and (meth)
React with acrylic acid The method for producing a (meth) acrylic acid ester according to claim 1, wherein 3. A curable resin composition containing the (meth) acrylic acid ester according to claim 1. 4. A cured product of the curable resin composition according to claim 3.