JPH04180904A - Photocurable composition - Google Patents

Abstract

PURPOSE:To obtain a photocurable composition which can give a cured product excellent in internal homogeneity, accuracy of surface transfer, an ability to cut ultraviolet rays, transparency and hue by adding a specified photopolymerization initiator and a specified ultraviolet absorber to a polyfunctional photopolymerizable acrylic monomer. CONSTITUTION:A photocurable composition comprising 100 pts.wt. polyfunctional photopolymerizable acrylic monomer, 0.01-0.3 pt.wt. photopolymerization initiator of the formula and 0.01-0.02 pt.wt. at least either a benzophenone ultraviolet absorber or a benzotriazole ultraviolet absorber. Examples of the polyfunctional acrylates which can be desirably used include 2,2-bis(4-methacryloyloxyphenyl) propane and 2,2-bis(4-methacryloyloxy-3,5-dibromophenyl)propane.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of industrial application) The present invention relates to a photocurable composition that is cured by irradiation with active energy rays such as ultraviolet rays, and particularly for the production of optical components such as lenses, prisms, mirrors, and optical discs. The present invention relates to a photocurable composition suitable for cast polymerization.

(Prior art) A method of manufacturing plastic lenses by irradiating a photocurable resin with ultraviolet rays from an ice statue lamp as active energy rays has already been proposed (4! ,
JP-A No. 63-207632, etc.). This method has the advantage that it can be cured in a short time by UV irradiation, but the internal homogeneity and surface transfer precision of the cured resin are not sufficient, and the transparency and hue of the cured resin are generally lower than that of polymethyl methacrylate. It has the disadvantage that it is inferior to polymers such as , polycarbonate, and diethylene glycol bisallyl carbonate.

For this reason, optical components such as lenses using conventional ultraviolet curable resins have had many practical discoveries.

(Problems to be Solved by the Invention) The present invention aims to improve the above-mentioned drawbacks of conventional photopolymerizable compositions for use in optical component manufacturing, and particularly improves internal homogeneity, surface transfer accuracy, and ultraviolet resistance. The present invention aims to provide a photocurable composition that provides a cured product with excellent properties such as cuttability, transparency, and hue, and is preferably a photocurable composition suitable for manufacturing optical components by cast polymerization.

(!!Solution for Pupils) According to the present invention, a photocurable composition containing a specific photopolymerization initiator and a specific ultraviolet absorber in a specific ratio in a photopolymerizable monomer is used to achieve the objective. This is what we were able to achieve.

That is, the photocurable composition of the present invention contains (B) the general formula (wherein, X is a methyl group, a methoxy group, or a chlorine atom , n represents the number 2 or 3, and R'Ii represents a phenyl group or a methoxy group.
~0.3 parts by weight, and (C) at least one UV absorber selected from benzophenone UV absorbers and benzotriazole UV absorbers in an amount of 0.0/~0. ,! It is a composition formed by containing in the ratio of the weight part.

Polyfunctional photopolymerizable acrylic monomer used in the present invention (
As A), various polyfunctional (meth)acrylates are used. "(Meth)acrylate" as described in this specification is a general term for acrylate and methacrylate.

Specific examples of polyfunctional acrylates used include:
General formula (wherein, R1 represents a hydrogen atom or a methyl group, 几 represents an alkylene group having 2 to 3 carbon atoms, Y represents a chlorine atom or a bromine atom, and J and m each represent O or 1 to 3 carbon atoms. The sum of ) and m is 0 to 6. R3 represents a hydrogen atom or a methyl group. ) A di(meth)acrylated metal having a bisphenol A or bisphenol F skeleton represented by the general formula (wherein R1 represents a hydrogen atom or a methyl group, R4 represents an alkylene group having 2 to /j carbon atoms, p represents an integer of /~l≠), and furthermore, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)
Examples include tri(meth)acrylate compounds such as acrylate and pentaerythritol tri(meth)acrylate.

Specific examples of particularly preferred polyfunctional acrylates include 2
．． 2-bis(≠-methacryloyloxyphenyl)propane, 22-bis(p-methacryloyloxy-3,j
-dibromphenyl)propane, 22-bis(≠-methacryloyloxyethoxyphenyl)propane, -2,
-2-His(Hiro-methacryloyloxyethoxy-3,
J''-dibromphenyl)propane 1.2-bis(≠-methacryloyloxyjetoxyphenyl)propane, 2,2-bis(tIt-methacryloyloxyshedquin-3,5-dibromphenyl)propane, ethylene Examples include glycol dimethacrylate, diethylene glycol dimethacrylate, trimethylene glycol dimethacrylate, Otsu-3-butylene dimethacrylate, Otsu-hexanediol dimethacrylate, and cicorbis(coome methacryloyloxycyclohexyl)propane.

The photopolymerization initiator used in the present invention has the above general formula (I)
These photopolymerization initiators may be used in combination of seven types, or in combination of two or more types.

Specific examples of the photopolymerization initiator include 2-dimethylbenzoyldiphenylphosphine oxide,
λ, trimethylbenzoyldiphenylphosphine oxide, 2<t.

O-trimethylbenzoylphenylphosphinic acid methyl ester, 21. -dichlorobenzoyldiphenylphosphine oxide, 2A-dimethoxybenzoyldiphenylphosphine oxide, and the like. A preferred photoinitiator is 23. O-trimethylbenzoyl diphenylphosphine oxide and trimethylbenzoyl phenylphosphine acid methyl ester.

The proportion of the photopolymerization initiator to be used is from o, oi to 0.3 parts by weight, preferably from 0.02 to 01.2 parts by weight, based on 100 parts by weight of the polyfunctional photopolymerizable acrylic polymer. If the proportion of the photopolymerization initiator is too high, the internal homogeneity of the cured resin will deteriorate and the hue will also deteriorate. Furthermore, if the amount of photopolymerization initiator is too small, the composition cannot be sufficiently cured.

The ultraviolet absorber used in the present invention is selected from benzophenone ultraviolet absorbers and benzotriazole ultraviolet absorbers, and seven types of ultraviolet absorbers may be used, or two or more types may be used in combination. You can.

Specific examples of the ultraviolet absorber used are U≠-dihydroxybenzophenone, 2-hydroxy-≠-methoxybenzophenone, 2-hydroxy-q-octoxybenzophenone, 2-hydroxy-≠-octadecyloxybenzophenone, 2.2'-dihydroxy-≠-methoxybenzophenone 1.2. j'-dihydroxy-% +'
-benzophenone compounds such as dimethoxybenzophenone, J-(,2'-hydroxy-!-methylphenyl)benzotriazole 1.2-(,2'-hydroxy-
Finished! '-ditertiarybutylphenyl)penztriazole, 2-(λ'-hydroxy-3'-tert-
These are benzotriazole compounds such as butyl-j'-methylphenyl)benzotriazole.

The proportion of these ultraviolet absorbers is from o, oi to 0.2 parts by weight, preferably from 0.03 to 0.7 parts by weight, based on 100 parts by weight of the polyfunctional photopolymerizable acrylic monomer. If the blending ratio of the ultraviolet absorber is too large, the cured product may not be sufficiently cured or the internal homogeneity of the cured product will deteriorate. Furthermore, if the proportion of the ultraviolet absorber is too small, the desired ultraviolet cut property cannot be obtained.

The photocurable composition of the present invention may contain other radically polymerizable compounds for the purpose of adjusting the optical properties of the cured product or adjusting the viscosity of the composition. Specific examples of other radically polymerizable compounds include monofunctional esters of acrylic acid and methacrylic acid such as methyl methacrylate and methyl acrylate, and aromatic vinyl compounds such as styrene, dibromustyrene, and divinylbenzene. can give.

Further, the photocurable composition of the present invention may contain a polymerization accelerator, a polymerization regulator, an antifogging agent, a mold release agent, and other additives as necessary.

The photocurable composition of the present invention can be easily polymerized and cured by irradiation with active energy rays, and the active energy rays preferably have a wavelength in the range of 200 to 000 nm.

The atmosphere in which active energy rays are irradiated is normal air,
Alternatively, it may be in an inert gas atmosphere. As a light source for active energy rays, a chemical lamp, a xenon lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, etc. are used.

Examples and comparative examples will be given and explained in detail below.

In these examples, "parts" refer to parts by weight.

Further, the physical properties of the cured resin described in these examples were determined by the following test method.

■ Light transmittance using a 2mm thick test piece! ; The transmittance of light of 00 nm was measured.

(2) Refractive index and Atsube number Measured at 23C using an Atsube refractometer (manufactured by Atago Corporation).

■ Optical distortion Measured using a Toshiba distortion tester (manufactured by Toshiba Glass Co., Ltd.), and those with no distortion were evaluated as ○, and those with distortion were evaluated as X.

Example/2.2-bis(II-~methacryloyloxyethoxyphenyl)propane (100 parts); ≠Otsu-trimethylpenzoyldiphenylphosphine oxide (hereinafter referred to as
It is called l'-TMDPOJ. ) 0.1 part 1.2-Hydroxy≠-octoxybenzophenone (Kyodo Yakuhin Co., Ltd. trade name Biosorb/30) 0.0 part was added, stirred and mixed uniformly, and defoamed to obtain a composition. 6mm thick made of glass plate with steel surface finish and silicone rubber.
The mold was cast under an argon gas atmosphere.

Next, from a distance of height ≠ Om from the glass surface of the mold, the output, ! i' OW/cm high pressure mercury lamp for 70 minutes (
Ultraviolet rays were irradiated from both sides of the glass for 5 minutes each.

After demolding the obtained cured product, it was placed in an air oven for 1ooc.
The resin was heated for 2 hours to obtain a colorless and transparent cured resin with no optical distortion.

This cured resin was cut and polished to the dimensions of a sample for measurement in order to measure its physical properties, and the results of measuring its physical properties were as shown in Table 1.

Used in Example/Example. 2. A composition was prepared in the same manner as in Example, except that 100 parts of triethylene glycol dimethacrylate was used instead of 100 parts of 2-bis(lA-methacryloyloxyethoxyphenyl)furopane, and cast in the same manner. The physical properties of the cured resin obtained by curing in the same manner were as shown in Table 1.

Example 3 In place of 100 parts of 2,2-bis(≠-methacryloyloxyethoxyphenyl)propane used in Example 1, 100 parts of Otsu-hexanediol dimethacrylate was used, and the rest was carried out in the same manner as in Example. A composition was prepared, cast and cured in the same manner, and the physical properties of the cured resin were measured in the same manner. The results were as shown in Table/.

Example 1 Instead of 77,100 parts of 22-bis(t-methacryloyloxyethoxyphenyl)furo used in Example 1, 22
-bis(≠-methacryloyloxyethoxyphenyl)
A composition was prepared using propane rom and 20 parts of 22-bis(dermethacryloyloxyethoxy3.!; -dibromphenyl)propane in the same manner as in Example/, and cast and cast in the same manner. It was cured, and the physical properties of the cured resin were measured in the same manner.

A colorless and transparent cured product with no optical distortion was obtained. The physical properties of the cured resin were measured in the same manner as in Example 1, and the results are shown in Table 2.

Example J Instead of the 2-hydroxy-μm octoxybenzophenone O, OS part used in Example/, 2-(2'-hydroxy-j'-methylphenyl)benzotriazole (Kyodo Yakuhin Co., Ltd. trade name Biosorb j, 20) A cured resin was obtained in the same manner as in Example, except that 0.0 parts of the resin was used and the ultraviolet irradiation time was changed from 70 minutes to 72 minutes (6 minutes each from both sides of the glass). The physical properties of the cured resin were as shown in Table.

Example 0.7 part of the photopolymerization initiator TMDPO used in Example 2 was replaced by 0.7 part of methyl ester of 24+, trimedelbenzoyl phenylfuos heptaonic acid, and the rest were as in Example. A cured resin was obtained in the same manner as in /. The physical properties of the cured resin are as shown in Table 1. 0.7 part of benzyl dimethyl ketal was used in place of 0.7 part of TMDPO used in Comparative Example/Example/, and the rest was the same as Example/. A cured resin was obtained. The physical properties of the cured resin are as shown in Table 1, and the cured resin in this case did not become colorless and transparent but had a yellow color.

Comparative Example A cured resin was obtained in the same manner as in Example except that 0.3 parts of the same compound was used in place of 017 parts of TMDPO used in Example. The physical properties of this cured resin are as shown in Table 1. The cured resin in this case did not become colorless and transparent, but had a yellow color and optical distortion.

Comparative Example 3 A composition was prepared in the same manner as in Example, except that 0.003 parts of the same compound was used in place of 0.7 parts of TMDPO used in Example, and the resulting composition was The molded product was cast in the same way for 20 minutes using the same high-pressure mercury lamp.
Although both sides of the glass were irradiated with ultraviolet rays for 70 minutes each, a cured product that could be removed from the mold was not obtained.

Comparative Example≠ Instead of 0.0 part of J-hydroxy-t-octoxybenzophenone used in Actual Full/, 0.11 part of the same compound was used.
A composition was prepared in the same manner as in Example 1, and cast in the same manner as above.It was irradiated with ultraviolet rays for 20 minutes (70 minutes on each side of the glass) using the same high-pressure mercury lamp. However, the cured product did not become removable.

(Effects of the Invention) The photocurable composition of the present invention can provide a cured product with excellent internal homogeneity, surface transfer accuracy, ultraviolet cut-off properties, transparency, and hue, and is advantageous for manufacturing optical components. Can be used.

Patent applicant: Mitsubishi Yuka Co., Ltd.

Claims (1)

[Claims] (1) For 100 parts by weight of (A) polyfunctional photopolymerizable acrylic monomer, (B) General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, X is a methyl group, a methoxy group, or (represents a chlorine atom, n represents the number 2 or 3, R represents a phenyl group or a methoxy group) at least one photopolymerization initiator represented by 0.01
~0.3 part by weight, and (C) at least one UV absorber selected from benzophenone UV absorbers and benzotriazole UV absorbers in a proportion of 0.01 to 0.2 parts by weight. A photocurable composition.