JPH04159306A - Photocurable composition - Google Patents

Abstract

PURPOSE:To obtain a photocurable composition suitable for the production of an optical component being good in inside homogeneity and accuracy of surface transfer, having an ability to cut ultraviolet rays and excelling in transparency and hue by mixing a specified diethylenically unsaturated monomer with a specified photopolymerization initiator and a specified ultraviolet absorber. CONSTITUTION:A photocurable composition is obtained by mixing 100 pts.wt. diethylenically unsaturated monomer of formula I (wherein A is a group of formula II, III or IV; R<1> to R<5> are each 1-8 C alkylene; and (l), (m) and (n) are each 0 or 1-4), e.g. a compound of formula V, VI or VII with 0.02-0.4 pt.wt. photopolymerization initiator selected between a benzophenone photoinitiator and an acetophenone photoinitiator (e.g. 1-phenyl-2-hydroxy-2-methylpropan-1-one) and 0.01-0.2 pt.wt. ultraviolet absorber selected between a benzophenone ultraviolet absorber and a benzotriazole ultraviolet absorber [e.g. 2,4- dihydroxybenzophenone or 2-(2'-hydroxy-5-methylphenyl) benzotriazole].

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a photocurable composition that is cured by irradiation with active energy rays such as ultraviolet rays, and more specifically, to optical components such as lenses, prisms, mirrors, and optical discs. The present invention relates to a composition for cast polymerization suitable for the production of.

[Prior art j A method has been proposed for manufacturing plastic lenses by irradiating a photocurable resin with ultraviolet rays from a mercury lamp or the like as active energy rays (Japanese Unexamined Patent Application Publication No. 61-194
No. 401, Japanese Unexamined Patent Publication No. 63-207632, etc.). These methods have the advantage of short-time curing by UV irradiation, but at present, internal homogeneity and surface transfer accuracy are insufficient, and the transparency and hue of lenses obtained by UV curing are generally poor. , polymethyl methacrylate, polycarbonate, and diethylene glycol bisallyl carbonate polymers.

Therefore, lenses obtained by conventional methods using such ultraviolet rays have many practical problems.

[Problems to be Solved by the Invention] The present invention has been made in order to improve the drawbacks of the conventional method described above. It is an object of the present invention to provide a composition for cast polymerization which has the following properties and is suitable for producing optical parts having excellent transparency and hue.

[Means for Solving the Problems] That is, the present invention provides: (A) 100 parts by weight of a diethylenically unsaturated monomer represented by the following formula [1], CH2=CH-@-CH2-A-CH2-@ -cH・C
H2 [■] (Here, A is -5-(-R'÷R2-5→", -5+R3-0→, R'-S-1 or -S + R
3-0-R5-0→, R'-5-, R1-R5 each represents an alkylene group having 1 to 8 carbon atoms, f, m
, n each represent O or an integer of 1 to 4. ) (B) 0.02 to 0.4 parts by weight of a photopolymerization initiator consisting of at least one selected from benzophenone photoinitiators and acetophenone photoinitiators; (C) benzophenone ultraviolet absorption and 0.2 parts by weight of an ultraviolet absorber consisting of at least one type selected from hensitriazole-based ultraviolet absorbers, in the above proportions.

The photopolymerizable monomer used in the present invention is a diethylenically unsaturated monomer represented by the cutting allowance [N, and as a specific example,
I can list the following:

A is -S + R'-0-)r-R"-S-, and CH2=CH A is -S + R3-0-R'-0→, R'-S-
Assuming that CH2-CH ■ CIl,=C1l "CH2=CH A is -s -+ R'-@-R2-s→, (where p is 4 or less excluding 0 (the number of 1-phenyl-2 indicates the degree of oligomerization).
-Hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexylphenylketone, 4-diphenoxydichloroacetophenone, jetoxyacetophenone, ■-(4-isopropylphenyl)-2-hydroxy-2-methylpropane- These include acetophenone compounds such as 1-one, benzophenone compounds such as benzophenone, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, and 3,3'-dimethyl-4-methoxybenzophenone.

Preferred photoinitiators are 1-phenyl-2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, benzophenone, methyl benzoylbenzoate, and diphenoxybenzophenone. These can be used alone or in combination of two or more, and are 0.02 to 0.4 parts by weight, preferably 0.02 to 0.4 parts by weight, based on 100 parts by weight of the sulfur-containing acrylic monomer of formula [1].
05 to 0.3 parts by weight is blended. If the amount of photopolymerization initiator is too large, not only the internal homogeneity of the resulting polymer will be poor (but also the hue will deteriorate).On the other hand, if the amount of photopolymerization initiator is too small, there will be insufficient Hardness cannot be obtained.

The ultraviolet absorbers used in the present invention include 2,4-dihydroxyhensiphenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, Benzophenone compounds such as 2,2'-dihydroxy-4-methoxybenzophenone and 2,2'-dihydroxy-4,4'-dimethoxybenzophenone;
2-(2'-hydroxy-5-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5
'-ditert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-tert-
hensitriazole compounds such as butyl-5'-methylphenyl)benzotriazole, which can be used alone or in combination of two or more, containing 100 parts by weight of the diethylenically unsaturated monomer of formula [1] 0.01~
It is blended in an amount of 0.2 part by weight, preferably 0.03 to 0.1 part by weight.

If the amount of ultraviolet absorber blended is too large, a sufficient degree of curing may not be obtained, or the internal homogeneity of the obtained cured product will be poor. On the other hand, if the amount of ultraviolet absorber is too small, desired ultraviolet blocking properties cannot be obtained.

In addition, the photocurable composition may optionally contain a polymerization accelerator,
A polymerization regulator, an antifogging agent, a mold release agent, and other additives can be blended.

In order to polymerize and cure the photocurable composition of the present invention by irradiation with active energy rays, a wavelength of 200 to 600 nm is required.
Active energy rays are preferred, and the irradiation atmosphere may be either normal air or an inert gas atmosphere. Further, as a light source, a known chemical lamp, xenon lamp, low-pressure mercury lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, metal halide lamp, etc. can be used.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

[Example] Specific examples will be shown to explain the present invention in more detail. Note that parts in the examples indicate parts by weight. The various physical properties obtained in the Examples were measured by the following test methods.

(1) Light transmittance: 50
The light transmittance at 0 part m was measured.

(2) Refractive index and Atsube number: Measured at 25°C using an Asohe refractometer (manufactured by Atago Corporation).

(3) Optical distortion 2 Measured with a Toshiba distortion tester (manufactured by Toshiba Glass Co., Ltd.), and those with no optical distortion were marked as ○, and those with optical distortion were marked as ×.

Example 1 Diethylenically unsaturated monomer of the following formula (1) CHz・CB÷
CHz-5-CHzl CHz-5-CHzlC)I・
CH2...(1) (However, the bond to both terminal aromatic nuclei is at the P-position 77m-position-
1-hydroxycyclohexyl-phenyl ketone (hereinafter abbreviated as monomer (1)) is added to 100 parts of monomer (1).
"Irgacure 184" (Chiha Geigy) 0.2 parts, 2-hydroxy-4-octoxybenzophenone ("
After adding 0.05 part of "Biosorb 130" (manufactured by Kyodo Yakuhin Co., Ltd.), stirring and mixing uniformly, defoaming, this liquid was placed in a 6M thick mold made of a mirror-finished glass plate and silicone rubber in an argon atmosphere. It was undercast. Then, ultraviolet rays were irradiated for 12 minutes (6 minutes on each side of the glass) from a high-pressure mercury lamp with an output of 80 W/cm from a distance of 40C1 from the glass surface. After demolding the obtained cured product, it was heated in an air oven at 100 °C for 2 hours to obtain a colorless and transparent product with no optical distortion. Thereafter, the sample was cut and polished to the dimensions of the measurement sample in order to measure its physical properties.

The results of physical property measurements were as shown in Table 1.

Example 2 Monomer (11,100 parts) in Example 1 was added to 8 parts of monomer (1).
Example 1 except that 0 parts and 20 parts of dipromostyrene were used.
In the same manner as above, a colorless and transparent cured product with no optical distortion was obtained. It was processed in the same manner as in Example 1 and its physical properties were measured. The measurement results were as shown in Table-1.

Example 3 100 parts of monomer (1) in Example 1 was replaced with monomer (1)
The same procedure as in Example 1 was carried out except that 80 parts of p-bis(β-methacryloyloxyethylthio)xylylene was used, to obtain a colorless and transparent cured product with no optical distortion. It was processed in the same manner as in Example 1 and its physical properties were measured. The measurement results were as shown in Table-1.

Example 4 0.05 part of 2-hydroxy-4-octoxybenzophenone in Example 1 was converted into 2-(2'-hydroxy-5'
- Methylphenyl) benzotriazole ("Biosorb 520" manufactured by Kyodo Yakuhin Co., Ltd.) 0.05 part and the ultraviolet irradiation time was changed from 12 minutes to 14 minutes (7 minutes on each side of the glass). A colorless and transparent cured product with no optical distortion was obtained. It was processed in the same manner as in Example 1 and its physical properties were measured. The measurement results were as shown in Table-1.

Example 5 The same procedure as in Example 1 was performed except that 0.2 parts of "Irgacure 184" in Example 1 was replaced with 0.2 parts of hensifhenone, to obtain a colorless and transparent cured product with no optical distortion. Example 1
The material was processed in the same manner as above and the physical properties were measured.

The measurement results were as shown in Table-1.

Example 6 The same procedure as in Example 1 was carried out except that monomer (1) in Example 1 was replaced with monomer (2) below to obtain a colorless and transparent cured product without optical distortion. It was processed in the same manner as in Example 1, and its physical properties were measured. The measurement results were as shown in Table-1.

C) 12=CH(toCHz-5-CHzCHz-0-C
HzCH2-5-CHz -()-CI(2CH! (However, the bond to both terminal aromatic nuclei is P-position/m-position = %
It is a mixture of ) Example 7 A cured product was obtained in the same manner as in Example 1, except that monomer (1) in Example 1 was replaced with monomer (3) below.

C1(2:CH-KichiCHz-5-C)IzCHz-0-
(Jlz-0-CHzCHz-5-CHz÷CH-CH
2 (However, the bond to the aromatic nucleus at both ends is a mixture of P-position/m-position = 2.) Comparative Example 1 0.2 part of Irgacure 184J in Example 1 was mixed with 0.2 part of diethylthioxanthone. Example 1 except that
A cured product was obtained in the same manner as above. However, it did not become colorless and transparent, but took on a yellow color. It was processed in the same manner as in Example 1 and its physical properties were measured. The measurement results were as shown in Table-1.

Comparative Example 2 1 part of "Irgacure 184JO" in Example 1 was added to 0.
A cured product was obtained in the same manner as in Example 1 except that the amount was changed to 5 parts. However, it did not become colorless and transparent, but took on a yellow color. Additionally, there was optical distortion. It was processed in the same manner as in Example 1 and its physical properties were measured. The measurement results were as shown in Table-1.

Comparative Example 3 The same procedure as in Example 1 was carried out except that 0.005 part of Irgacure 184 J O,1,O in Example 1 was used. Even when irradiated with , a cured product that could be removed from the mold was not obtained.

Comparative Example 4 Example 1 except that 0.05 part of 2-hydroxy-4-octoxybenzophenone in Example 1 was replaced with 0.4 part.
operated in the same way. However, even after irradiating the glass with ultraviolet rays for 20 minutes (10 minutes on each side of the glass), no cured product that could be removed from the mold was obtained.

Claims (1)

[Claims] (1), (A) 100 parts by weight of a diethylenically unsaturated monomer represented by the following formula [I], ▲There are mathematical formulas, chemical formulas, tables, etc.▼[I] (Here, A is ▲Mathematical formulas, chemical formulas, etc.) , there are tables, etc. ▼, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, or ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, and R^1 to R^5 are alkylene with 1 to 8 carbon atoms, respectively. 1, m, and n each represent 0 or an integer of 1 to 4.) (B) The photopolymerization initiator is at least one selected from benzophenone photoinitiators and acetophenone photoinitiators. (C) 0.02 to 0.4 parts by weight of a photopolymerization initiator consisting of; (C) 0.01 to 0.2 parts by weight of an ultraviolet absorber consisting of at least one selected from benzophenone ultraviolet absorbers and benzotriazole ultraviolet absorbers; A photocurable composition comprising , in the above proportions.