JPH0820561B2 - High refractive index optical resin - Google Patents

Description

TECHNICAL FIELD The present invention relates to an optical resin, and more specifically, it is a high-refractive-index optical that is excellent in transparency and has a high refractive index, which is useful for plastic lenses for eyeglasses and the like. For resins.

<Prior Art> In recent years, a synthetic resin material excellent in lightness, moldability, impact resistance and dyeability has been used as an optical material such as a plastic lens instead of the inorganic glass. Known examples of the synthetic resin material include polymethyl methacrylate, polydiethylene glycol bisallyl carbonate, polystyrene, and polycarbonate.
The polymethylmethacrylate and polyethylene glycol bisallyl carbonate are lightweight and have excellent impact resistance, but when used as a lens because the refractive index is low at about 1.49, a thicker lens than inorganic glass is required, Therefore, it has a drawback that it is not suitable for high magnification and light weight. Further, in the polystyrene and polycarbonate, although the refractive index is as high as about 1.58 to 1.59, since these are thermoplastic resins, there is a problem that optical distortion easily occurs due to birefringence during injection molding. There are drawbacks such as inferior properties and scratch resistance.

Therefore, various technical proposals have recently been made in order to improve these conventional defects. For example, JP-A-53-77
No. 87, a copolymer of diethylene glycol biscarbonate and diallyl isophthalate, JP-A-59-8131.
No. 8 discloses a copolymer of diallyl phthalate and unsaturated fatty acid alcohol benzoate and JP-A-59-19.
Japanese Patent No. 1708 discloses di (meth) having bisphenol A.
A copolymer of acrylate, diallyl isophthalate and diethylene glycol bisallyl carbonate is disclosed. However, each of the resins proposed above has a problem that the refractive index is as low as 1.52 to 1.56 and unreacted allyl monomer is likely to remain.

Further, JP-A-57-28115 discloses a copolymer of a styrene-based vinyl monomer and an unsaturated carboxylic acid heavy metal salt,
JP-A-60-55007 discloses a copolymer of a halogen-substituted diallyl phthalate and a halogen-substituted allyl benzoate, which are 1.58 to 1.60 in terms of refractive index.
Although high, the specific gravity of the polymer is large, and there is a drawback that the weight cannot be reduced.

Further, in JP-A-55-13747, a copolymer of halogen-substituted styrene, di (meth) acrylate having bisphenol A, a benzyl methacrylate-based monomer, and a phenol methacrylate-based monomer is disclosed in JP-A-59-13.
In 133211, hydroxydi (meth) acrylate having an aromatic ring, a copolymer of a diisocyanate compound and a styrene monomer is proposed, but in the case of these resins, the refractive index is as high as around 1.60. However, it has the drawbacks that it is difficult to control the polymerization reaction, the specific gravity of the polymer is large, and there is a problem in weather resistance.

<Problems to be Solved by the Invention> An object of the present invention is to have desirable optical transparency as a plastic lens or other optical resin, and also excellent in weather resistance, solvent resistance and impact resistance. Is to provide a high refractive index optical resin having a small specific gravity.

<Means for Solving the Problems> According to the present invention, the following general formula (I) (In the formula, X represents a halogen atom, R ₁ represents an alkylene group, R ₂ represents a carbonyl group or an alkylene group, R ₃ represents a hydrogen atom or a methyl group, and n, m and l are 0 to Three
Indicates an integer. However, a high refractive index optical resin obtained by polymerizing a raw material monomer containing an organic sulfur compound represented by 1 ≦ m + 1 ≦ 3 is provided.

 The present invention will be described in more detail below.

The high refractive index optical resin of the present invention is characterized by containing a specific organic sulfur compound as an essential raw material monomer.

The organic sulfur compound used in the present invention can be represented by the following general formula (I), In the formula, X represents a halogen atom, R ₁ represents an alkylene group, R ₂ represents a carbonyl group or an alkylene group, and R ₃ represents a hydrogen atom or a methyl group. Also, n, m and l are 0 to 3
Indicates an integer. However, 1 ≦ m + l ≦ 3. If m + 1 exceeds 3, the production is difficult.

Examples of the organic sulfur compound represented by the general formula (I) include 1- (p (m) -vinylbenzylthio) -2.
-((Meth) acryloylthio) ethane, 1- (p
(M) -Vinylbenzylthio) -2-((meth) allylthio) ethane, 1- (p (m) -vinylbenzylthio)
-5-((meth) acryloylthio) diethyl ether, 1- (p (m) -vinylbenzylthio) -5-
((Meth) allylthio) diethyl ether, 1- (p
(M) -Vinylbenzylthio) -5-((meth) acryloylthio) diethylthioether, 1- (p (m)-
Vinylbenzylthio) -5-((meth) allylthio) diethylthioether, 1- (p (m) -vinylbenzylthio) -8-((meth) acryloylthio) -3,6-dioxaoctane, 1- ( p (m) -vinylbenzylthio) -8-((meth) allylthio) -3,6-dioxaoctane, 1- (o-bromo-p-vinylbenzylthio)
-2- (acryloylthio) ethane and the like can be mentioned, and when used, they can be used alone or as a mixture.

To prepare the organic sulfur compound, for example, a corresponding dithiol compound is reacted with chloromethylstyrene, and then methacrylic acid chloride, acrylic acid chloride, methallyl chloride, allyl chloride is cupped in a suitable solvent. It can be easily obtained by a method such as ringing.

The mixing ratio of the organic sulfur compound in the raw material monomer is not particularly limited, but is preferably 1 to 100% by weight, particularly preferably 50 to 95% by weight, based on the entire raw material monomer. . Further, when the organic sulfur compound is blended in the range of 1 to 30% by weight, it can be used as a high-performance crosslinking agent having a high refractive index.

In the present invention, as the monomer other than the organic sulfur compound that can be used as the raw material monomer component,
For example, styrene, p-methylstyrene, p-chlorostyrene, o-chlorostyrene, p-bromostyrene, o-
Bromstyrene, vinyl acetate, vinyl propionate, methyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, phenyl methacrylate, phenyl acrylate, benzyl acrylate,
Benzyl methacrylate, bromphenyl methacrylate, acrylonitrile, methacrylonitrile, 2,2-bis (4-methacryloyloxyethoxyphenyl) propane, 2,2-bis (4-acryloyloxyethoxyphenyl) propane, diethylene glycol bisallyl carbonate, tetrachloro Diallyl phthalate, diallyl phthalate, p-divinylbenzene, m-divinylbenzene, divinylbiphenyl, ethylene glycol bis methacrylate, diethylene glycol bis methacrylate, ethylene glycol bis acrylate, diethylene bis acrylate, dipropylene glycol bis methacrylate, triethylene glycol bis acrylate,
Preferred examples include tetraethylene glycol bisacrylate, bisphenol A bismethacrylate, diallyl tetrachlorophthalate, diallyl isophthalate, allyl methacrylate, propylene glycol bisacrylate, hexaethylene glycol bisacrylate, octaethylene glycol bisacrylate, decane ethylene glycol bisacrylate. be able to.

The high refractive index optical resin of the present invention can be prepared, for example, by heat-polymerizing a raw material monomer in the presence of a radical polymerization initiator. As the radical polymerization initiator, an organic peroxide having a 10-hour half-life temperature of 160 ° C. or lower, an azo compound, or the like can be used. Specifically, for example, diisopropyl peroxydicarbonate, tertiary butyl peroxy-2- Ethyl hexanoate, tert-butyl peroxypivalate, tert-butyl peroxydiisobutyrate, lauroyl peroxide, t-butyl peroxyacetate, tert-peroxy octoate, tert-butyl peroxybenzoate, azobisisobutyronitrile, etc. ,
When used, they can be used alone or as a mixture. The amount of the radical polymerization initiator used is preferably 10 parts by weight or less, and particularly preferably 5 parts by weight or less, based on 100 parts by weight of the raw material monomer.

In order to carry out the heat polymerization, for example, the raw material monomer and the radical polymerization initiator may be charged directly into a desired mold, and preferably heated at 0 to 200 ° C. for 1 to 48 hours for polymerization. At this time, it is desirable that the polymerization is carried out under an atmosphere of an inert gas such as nitrogen, carbon dioxide or helium. In addition, before the polymerization, after prepolymerizing the raw material monomer, for example, 0 to 200 ° C. for 0.5 to 48 hours,
It is also possible to charge in a desired mold and post-polymerize.

<Effects of the Invention> The high-refractive-index optical resin of the present invention has a high refractive index of 1.60 or more, has a small optical strain, and has optical transparency, heat resistance, solvent resistance, and resistance to solvent. It is excellent in impact resistance and has a low specific gravity and can be made lightweight. Further, since reaction control and molding at the time of curing and polymerization are easy, it is useful as a plastic lens such as a lens for glasses, a camera lens, an optical material, or other optical resin material.

<Example> Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1 1- (p-vinylbenzylthio) -2- (acryloylthio) ethane (the structural formula; 2.4 g, 1- (m-vinylbenzylthio) -2- (acryloylthio) ethane (the structural formula; 0.05 g of tertiary butyl peroxybenzoate was added to and mixed with a raw material monomer composed of 3.6 g and 6 g of styrene to obtain a monomer composition. Then, after charging the monomer composition into two glass molds, the monomer composition was placed in a constant temperature bath at 80 ° C., heated at a curing temperature of 80 ° C. for 6 hours, and further heated for 10 hours in 3 hours.
The temperature was raised to 0 ° C. and finally annealed at 100 ° C. for 2 hours to obtain a cured resin. The obtained cured resin was taken out of the mold, and the refractive index, Abbe number and transparency were measured according to the following methods. Table 1 shows the results.

Refractive index and Abbe number ... Measured using an Abbe refractometer (manufactured by Atago Co., Ltd.).

Transparency: The one having transparency as observed with the naked eye was marked with ◯, and the one slightly clouding was marked with Δ.

Examples 2-6 Instead of the raw material monomer of Example 1, 1- (p-vinylbenzylthio) -5- (acryloylthio) diethyl ether (the structural formula; 28 parts by weight and 1- (m-vinylbenzylthio) -5- (acryloylthio) diethyl ether (structural formula; A raw material monomer (Example 2) consisting of 42 parts by weight and 130 parts by weight of p-chlorostyrene was added to 1- (p-vinylbenzylthio) -5- (methallylthio) diethyl ether (structural formula; 40 parts by weight and 1- (m-vinylbenzylthio) -5- (methallylthio) diethylthioether (structural formula; 60 parts by weight of the raw material monomer (Example 3)
(P-Vinylbenzylthio) -5- (allylthio) diethylthioether (Structural formula; 40 parts by weight and 1- (m-vinylbenzylthio) -5- (allylthio) diethylthioether (structural formula; 60 parts by weight of a raw material monomer (Example 4), and 1- (p-vinylbenzylthio) -8- (acryloylthio) -3,6-dioxaoctane (the structural formula; 28 parts by weight and 1- (m-vinylbenzylthio) -8- (acryloylthio) -3,6-dioxaoctane (structural formula; A raw material monomer (Example 5) consisting of 42 parts by weight and 30 parts by weight of methyl methacrylate was added to 1- (o-bromo-p-
Vinylbenzylthio) -2- (acryloylthio) ethane (structural formula; A cured resin was prepared and each measurement was performed in the same manner as in Example 1 except that the raw material monomer (Example 6) consisting of 50 parts by weight and 50 parts by weight of styrene was used. The results are shown in Table 1.
Shown in

Comparative Examples 1 and 2 A cured resin was prepared in the same manner as in Example 1 except that the vinyl-based monomer shown in Table 2 was used, and each measurement was performed. The results are shown in Table 2.

Claims (1)

[Claims] 1. The following general formula (I): (In the formula, X represents a halogen atom, R ₁ represents an alkylene group, R ₂ represents a carbonyl group or an alkylene group, R ₃ represents a hydrogen atom or a methyl group, and n, m and l are 0 to 3 Where 1 ≦ m + l ≦ 3), a high refractive index optical resin obtained by polymerizing a raw material monomer containing an organic sulfur compound represented by the formula: