JPH04180911A - Curable composition - Google Patents

Abstract

PURPOSE:To obtain a curable composition which can give a cured product excellent in internal homogeneity, accuracy of surface transfer, transparency and hue by mixing a photopolymerizable diethylenically unsaturated monomer with a specified photopolymerization initiator and a specified organic peroxide. CONSTITUTION:100 pts.wt. photopolymerizable diethylenically unsaturated monomer {e.g. p-bis[beta-(meth)acryloyloxyethylthio]xylylene} is mixed with 0.01-0.3 pt.wt. photopolymerization initiator of the formula (wherein X is methyl, methoxy or Cl; R is phenyl or methoxy; and(n) is 2 or 3) and 0.02-0.5 pt.wt. organic peroxide of a 10-hr half-life temperature of 50-95 deg.C [e.g. 1,1-bis(tert. butylperoxy)-3,3,5-trimethylcyclohexane].

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 is particularly applicable to the production of optical components such as lenses, prisms, mirrors, and optical discs. The present invention relates to photocurable compositions suitable for cast polymerization.

(Prior art) A method of manufacturing plastic lenses by irradiating a photocurable resin with ultraviolet rays from a mercury lamp as active energy rays has already been proposed (Tokuzui Sho 1./-/9 Sanda Oi No. , JP-A No. 67-207632, etc.). This method is
Although it has the advantage of being able to be cured in a short time by UV irradiation, the internal homogeneity and surface transfer precision of the cured resin are not sufficient, and the transparency and hue of the cured resin that is obtained is generally lower than that of polymethyl methacrylate or polycarbonate. However, it has the disadvantage that it is inferior to polymers such as diethylene glycol bisallyl carbonate.

For this reason, conventional optical components such as lenses using this type of ultraviolet curable resin have had many problems in practical use.

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

(Means for Solving the Problem) According to the present invention, the purpose can be achieved by a photocurable composition in which a photopolymerizable monomer contains a specific photopolymerization initiator and a specific organic peroxide in a specific ratio. This is something we were able to achieve.

That is, the curable composition of the present invention comprises (A) photopolymerizable diethylenically unsaturated monomer 100
Based on parts by weight, CB) Represented by the general formula (wherein, At least seven types of photoinitiators are o, oi
0.3 parts by weight, and (C) 0.02 to 0.3 parts by weight of an organic peroxide whose IO time half-life temperature is in the range of jO to rijC.

Examples of the photopolymerizable diethylenically unsaturated monomer used in the present invention include p-bis[β-(meth)acryloyloxyetherdeo]xylylene, m-bis[β-(
meth)acryloyloxyethylthioxylylene, p
-bis[β-(meth)acryloyloxyethyloxyethylthio]xylylene, m-bis[β-(meth)acryloyloxyethyloxyethyltheo]xylylene,
Sulfur-containing di(meth)acrylates such as false′-bis[β-(meth)acryloyloxyethylthiococyphenylsulfone, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di (meth)acrylate,
Alkylene glycol di(meth)acrylates such as propylene glycol di(meth)acrylate and hexanediol di(meth)acrylate, 2.2-bis[tei-(meth)acryloyloxyphenyl]propane, halogen derivatives thereof, 2.2 -bis(tei-C2-methacrytetrayloxyethoxy)phenyl]propane, bisphenol human skeleton-containing di(meth)acrylates such as its halogen derivatives, m-bis((44-vinylphenyl)methylthio)xylyle β, / Examples include styrenic compounds such as '-'s((≠-vinylphenyl)methylthio]diethyl ether.Particularly preferred diethylenically unsaturated monomers include p-bis[β-(meth)acryloyloxyethylthio ] cycrylene, m-bis[β-(
O sulfur-containing di(meth)acrylates such as meth)acryloyloxyethylthioxylylene, etc. or acrylate and methacrylate.

The general formula (B) of the photopolymerization initiator used in the present invention is (
Specific examples of the compound represented by 1) include dirodimethylbenzoyldiphenylphosphine oxide, 2pseudo-6-drimetherpenzoyldiphenylphosphine oxide), LtA, A-) methyl limethylbenzoylphenylphosphinate. ester, 2,6-cyclobenzoyldiphenylphosphinoxai)”
, 2j-dimethoxybenzoyldiphenyl 7-osphine oxide, and the like. A particularly preferred photopolymerization initiator is 241. j-t IJ methylbenzoyldiphenyl 7-osphine oxide and hydromethylbenzoylphenylphosphinic acid methyl ester.

These photopolymerization initiators may be used alone or in combination of 2ai or more. The proportion of the photopolymerization initiator used is from o, oi to 0.3 parts by weight, preferably 0.0 parts by weight, based on 100 parts by weight of the diethylenically unsaturated monomer.
It is 2 to 0.2 parts by weight. If the proportion of the photopolymerization initiator is too high, the internal homogeneity of the cured product (cured resin) will not only deteriorate, but also the hue will deteriorate. Moreover, if the proportion is too small, the composition will not be sufficiently cured.

The organic peroxide (C) used in the present invention has a half-life temperature of IO time! It is within the range of O~rijC.

Specific examples thereof include peroxyketals such as /, l-bis(tert-butylperoxy)-3,j, j-trimethylcyclohexane, /, l-bis(tert-butylperoxy)-cyclohexane, and tert- Peroxy esters such as butyl peroxy bivalate, tert-butyl peroxy (-monoethylhexanoate), tert-butyl peroxy isobutyrate,! ,! ,! Examples include diacyl peroxides such as t-trimethylhexanoyl peroxide, lauroyl peroxide, and benzoyl peroxide. These organic peroxides may be used alone or in combination of two or more.

The blending ratio of the organic peroxide is 0.02 to 0.00! with respect to 100 parts by weight of the diethylenically unsaturated monomer. Parts by weight, preferably 0. Oj -0.3 parts by weight. If the blending ratio of the organic peroxide is too large, not only will the hue of the cured product deteriorate, but also the mechanical properties of the cured product will deteriorate in some cases. Moreover, if the ratio is too small, the composition will not be sufficiently cured.

The curable composition of the present invention may contain an ultraviolet absorber, a polymerization accelerator, a polymerization control agent, an antifogging agent, a mold release agent, and other additives as necessary.

The curable composition of the present invention can be polymerized and cured by appropriately combining polymerization by active energy ray irradiation and heating polymerization. For example, a method of further heating polymerization after polymerization by irradiation with active energy rays such as ultraviolet rays,
A method of polymerizing by heating simultaneously with active energy ray irradiation,
Alternatively, polymerization and curing can be carried out using a method of irradiating one active energy ray after preliminary heating polymerization. Among these polymerization and curing methods, from the viewpoint of the degree of curing, internal homogeneity, hue, etc. of the polymerized and cured product, the method of first irradiating with active energy rays such as ultraviolet rays and then heating and polymerizing is preferred.

As a light source for the active energy ray irradiation, a chemical lamp, a xenon lamp, a low pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, etc. are used as appropriate.

Moreover, although any temperature can be used for thermal polymerization, the temperature is usually determined by taking into consideration the decomposition temperature of the organic peroxide used. - For boat fishing, temperatures in the range 70 to l≠O are used.

Further details will be given below with reference to Examples and Comparative Examples. In these examples, the parts mentioned refer to parts by weight.

Further, the physical properties of the cured products described in these examples were measured using the following test method.

(2) Light transmittance Using a test piece with a thickness of 2 mm, the light transmittance of Joonm was measured.

(2) Refractive index and Atsube number Measured at 2jC using an Atsube refractometer (manufactured by Atago Co., Ltd.).

(2) Optical distortion Measured with a Toshiba distortion tester (manufactured by Toshiba Glass Co., Ltd.), and those with no distortion were rated as × and those with O1 distortion.

Example 1 A sulfur-containing methacrylic compound represented by the structural formula (this is referred to as monomer ①. > 2.4I, A- in the ioo part) 13
/ 0.03 part of thylbenzoyl diphenylphosphine oxide (referred to as TMDPJ), t-butylperoxy-coethylhexanoate (manufactured by NOF Corporation)
After adding 0.2 parts and stirring and mixing uniformly, the mixture was defoamed to obtain a composition.

This composition was injected under an argon atmosphere into a mold having a thickness of A mm and made of a mirror-finished glass plate and silicone rubber. Next, the height of the glass surface of the mold is 41
Ultraviolet rays were irradiated from a distance of 0 es for 1 minute using a high-pressure mercury lamp with an output of 10 Vi/exs (from both sides of the glass for each interval). After removing the obtained cured product from the mold, it was heated at 10OC for 2 hours in an air-open environment to obtain a colorless and transparent cured product with no optical distortion.

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

Example 0.100 parts of the monomer used in Example 1 was replaced with io0 parts of a sulfur-containing methacrylic compound (referred to as monomer Ⅰ) represented by the structural formula, and the rest was the same as in Example 1.
A composition was prepared in the same manner as above, and when it was cast and cured in the same manner, a colorless and transparent cured product with no optical distortion was obtained.

The physical properties of this cured product were as shown in Table 1.

Example 3 In place of 2 parts of t-butylperoxy-coethylhexanoate O0 used in Example 1, 0.2 parts of 1-butyl peroxybivalate (manufactured by NOF Corporation) was used, and among them, A composition was prepared in the same manner as in Example 1, and cast and cured in the same manner to obtain a colorless and transparent cured product with no optical distortion.

The physical properties of this cured product were as shown in Table/.

Example 1 K, /, /-bis(t-butylperoxy) -J, j, j -trimethyl instead of 0.2 part of t-butylperoxy-2-ethyl hexaphate used in Example 1 A composition was prepared using 0.2 part of cyclohexane (manufactured by NOF Corporation) in the same manner as in Example 1, and cast and cured in the same manner to obtain a colorless and transparent cured product with no optical distortion. Obtained.

The physical properties of this cured product are shown in Table 1).

Example! In place of 03 parts of TMDPO used in Example 1, 2 false 4
A composition v4#! was prepared in the same manner as in Example 1 except that 0.02 part of -19 methylbenzoyl phenylphosphinic acid methyl ester was used. A cured product with no optical distortion was obtained by casting and curing in the same manner.

The physical properties of this cured product were as shown in Table 1).

Comparative Example 1 A composition was prepared in the same manner as in Example 1 using TMDPo used in Example, 0.7 parts of DK, and 0.06 parts of benzyl dimethyl ketal, and cast and cast in the same manner. When cured, the cured product did not become colorless and transparent but had a yellow color.

The physical properties of this cured product were as shown in Table 1.　　.

Comparative Example A composition was prepared in the same manner as in Example 1 except that 003 parts of the same compound was used in place of 07 parts of TMDPo used in Example 1, and cast and cured in the same manner. However, the cured product did not become colorless and transparent, but had a yellow color] and had optical distortion.

The physical properties of this cured product were as shown in Table 7.

Comparative Example 3 A composition was prepared in the same manner as in Example 1 except that TMDPo used in Example 1, 0 parts of K), and 0.00 parts of the same compound were used, and cast in the same manner. Afterwards, ultraviolet rays were irradiated using the same light source for 76 minutes (t minutes from each side of the glass), but no cured product was obtained that could be removed from the mold.

Comparative Example μ A composition was prepared in the same manner as in Example 1 without using the t-budelperoxy-coethylhexanoate used in Example 1, and cast and cured in the same manner. However, the cured product obtained by heating after demolding was brittle and could not be cut.

Comparative Example J The same procedure as in Example 1 was carried out except that diisopropylperoxydicarbonate)O,jiSe was used in place of 0.2 part of t-butylperoxy-coethylhexanoate used in Example. When a composition was prepared and cast and cured in the same manner, the cured product obtained by heating after demolding was too brittle to be cut.

Comparative Example 6 A composition was prepared in the same manner as in Example 1 except that 7.0 parts of the same compound was used in place of 0.2 parts of t-butylperoxy-2-ethylhexanoate used in Example 1. Prepare
When cast and cured in the same manner, the cured product did not become colorless and transparent, but had a yellow color and optical distortion.

The physical properties of this cured product were as shown in Table 1.

(Effects of the Invention) The photocurable composition of the present invention can provide a cured product with excellent internal homogeneity, surface transfer accuracy, transparency, and hue,
It can be advantageously used for manufacturing optical components.

Patent originator: Mitsubishi Yuka Co., Ltd.

Claims (1)

[Claims] (1) (A) Photopolymerizable diethylenically unsaturated monomer 10
(B) General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, X represents a methyl group, methoxy group or chlorine atom, n represents the number of 2 or 3, R represents a phenyl group or a methoxy group) at least one photopolymerization initiator represented by 0.01
-0.3 parts by weight, and (C) 0.02 to 0.5 parts by weight of an organic peroxide having a 10-hour half-life temperature in the range of 50 to 95°C.