JPH04325505A - Optical resin - Google Patents

Abstract

PURPOSE:To obtain an optical resin improved in refractive index, optical transparency, heat resistance, solvent resistance, impact resistance and handleability by polymerizing and curing a monomer composition containing two specified compounds. CONSTITUTION:A monomer composition is obtained by mixing 20-80 wt.% compound of formula I (wherein R1 is H or methyl; and x is H, Cl or Br) with 5-50wt. % compound of formula II (wherein R2 is H or methyl) and 0-50wt.% monomer such as 2,2-bis[4-{(meth)acryloxyethylenoxy-phenyl]propane or p-vinylbenzene. 100 pts. wt. this composition is cured by polymerization at 0-200 deg.C for 1-48hr in an inert gas atmosphere in the presence of at most 10 pts. wt. radical polymerization initiator having a 10-hr half-life temperature of 160 deg.C or below.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to mechanical properties, refractive index,
This invention relates to optical resins that have excellent optical properties such as chromatic aberration.

0002

BACKGROUND OF THE INVENTION In recent years, synthetic resin materials that are lightweight, easy to mold, have excellent impact resistance, and are dyeable have been used as plastic lens materials in place of inorganic glass. As the synthetic resin material, for example, polymethyl methacrylate, polydiethylene glycol bisallyl carbonate, polystyrene, polycarbonate, etc. are known, but the polymethyl methacrylate and polydiethylene glycol bisallyl carbonate have excellent lightness and impact resistance. However, since it has a low refractive index of about 1.49, when used as a lens, it requires a thicker lens than inorganic glass, and has the disadvantage that it is not suitable for increasing magnification or reducing weight. Furthermore, although polystyrene and polycarbonate have a high refractive index of about 1.58 to 1.59, since they are thermoplastic resins, they have the problem of easily causing optical distortion due to birefringence during injection molding. It has drawbacks such as lack of solvent resistance and scratch resistance.

[0003]Recently, therefore, several technical proposals have been made to improve the above-mentioned drawbacks of the conventional materials with a high refractive index. For example, JP-A-1-309002 discloses a plastic lens made by curing a distyryl-type organic sulfur compound and a trivalent or tetravalent thiol compound; Furthermore, a sulfur-containing plastic lens is produced by mixing and curing a compound having 1.3 or more vinyl groups on a molar average and a compound having 1.1 or more thiol groups on a molar average in a specific ratio. JP-A No. 2-58001 proposes a high refractive index optical resin obtained by reacting a dimercaptobenzene nuclear substitute with a compound having at least two reactive unsaturated groups per molecule. . However, although the above-mentioned sulfur-containing optical resin has a high refractive index, the relatively low molecular weight thiol compound used as a raw material has a strong odor when heated, causing problems in terms of the working environment.
Furthermore, there is a problem in that the composition has a high viscosity, resulting in poor handling properties. Furthermore, condensation polymerization compositions have problems such as poor yields because it is difficult to control polymerization during curing.

0004

[Problems to be Solved by the Invention] Therefore, an object of the present invention is to create a resin that has desirable refractive index, chromatic aberration, transparency, etc. as a resin for plastic lenses or other optical applications, has excellent various mechanical properties, and has a low specific gravity. Another object of the present invention is to provide an optical resin with low odor and excellent handling properties during curing.

[0005]

[Means for Solving the Problems] According to the present invention, a compound represented by the following general formula 3 (hereinafter referred to as component A),
An optical resin obtained by polymerizing and curing a raw material monomer composition containing a compound represented by the following general formula 4 (hereinafter referred to as component B) as an essential component is provided.

[0006]

[Chemical formula 3]

[0007]

[C4]

The present invention will be explained in more detail below.

Component A used as a raw material monomer composition in the present invention is a compound represented by the above general formula 3, and specific examples include styrene, α-methylstyrene, p-chlorostyrene, m-chlorostyrene. , p-bromostyrene, m-bromostyrene, and mixtures thereof.

Component B used as a raw material monomer composition in the present invention is a compound represented by the above general formula 4, and is 2,2-bis[4-(2'-hydroxy-
3'-acryloxypropyleneoxy)phenyl]propane, 2,2-bis[4-(2'-hydroxy-3'-
methacryloxypropyleneoxy)phenyl]propane and mixtures thereof.

The blending ratio of component A and component B in the present invention varies depending on the combination with other raw material monomer components, but preferably 20 to 80% by weight of component A and 5 to 50% by weight of component B. At this time, if the blending ratio of component A is less than 20% by weight, a sufficient refractive index cannot be obtained;
If the amount is more, sufficient mechanical strength cannot be obtained, so it is preferably within the above range. Furthermore, if the blending ratio of component B is less than 5% by weight, sufficient heat resistance cannot be obtained;
If it exceeds % by weight, a sufficient refractive index cannot be obtained, so it is preferably within the above range.

[0012] Furthermore, the raw monomer composition components used in addition to component A and component B, which are essential components in the present invention, are specifically, for example, 2,2-bis[4-
(meth)acryloxyethyleneoxy)phenyl]propane, 2,2-bis[4-((meth)acryloxydiethyleneoxy)phenyl]propane, 2,2-bis[4
-((meth)acryloxypolyethyleneoxy)phenyl]propane, 2,2-bis[3,5-dibromo-4-
(meth)acryloxydiethyleneoxy)phenyl]propane, p-vinylethylbenzene, m-vinylethylbenzene, p-divinylbenzene, m-divinylbenzene, methyl (meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glyco -di(meth)acrylate, triethylene glycol di(meth)
Acrylate, polyethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate
Polypropylene glycol di(meth)acrylate, 2-hydroxy-1-acryloxy-3-methacryloxypropane, 1,3-butylene glycol di(meth)acrylate
Acrylate, trimethylolpropane trimethacrylate, tetramethylolmethane tri(meth)acrylate
tetramethylolmethanetetraacrylate, dipentaerythritol hexaacrylate, glycidyl methacrylate, glycidyl allyl ether, (meth)acrylic acid adduct of glycerin diglycidyl ether, dibenzyl itaconate, dibenzyl Preferred examples include mesaconate, dibenzyl fumarate and mixtures thereof. The blending ratio of the compound to component A and component B is preferably 0 to 50% by weight, and 50% by weight.
If the amount is more, a sufficient refractive index cannot be obtained, so it is preferably within the above range. In addition, the said compound can be obtained by a well-known method.

The high refractive index optical resin of the present invention can be prepared, for example, by subjecting the raw material monomer composition to light or heat polymerization in the presence of a radical polymerization initiator. As the radical polymerization initiator, an organic peroxide or an azo compound having a 10-hour half-life temperature of 160° C. or lower can be used. Specifically, for example, benzoyl peroxide, diisopropyl peroxydicarbonate, tert-butyl peroxy-2-ethylhexanoate,
Tertiary butyl peroxypivalate, Tertiary butyl peroxy neodecanoate, Tertiary butyl peroxy diisobutyrate, Lauroyl peroxide, Tertiary butyl peroxy acetate, Tertiary peroxy octoate, Tertiary butyl peroxy benzoate, Azobis Examples include isobutyronitrile, which can be used alone or as a mixture. The amount of the radical polymerization initiator used is 10 parts by weight or less, particularly preferably 5 parts by weight, based on 100 parts by weight of the raw material monomer composition.
It is desirable that the amount is less than parts by weight.

[0014] In order to carry out the heating polymerization, for example, the raw material monomer composition and the radical polymerization initiator are directly charged into a desired mold, and the polymerization is carried out by heating preferably at 0 to 200°C for 1 to 48 hours. can be done. At this time, the polymerization system is preferably carried out under an inert gas atmosphere such as nitrogen, carbon dioxide, or helium. In addition, before the polymerization, the raw material monomer composition may be mixed, for example, from 0 to
After prepolymerizing at 200° C. for 0.5 to 48 hours, it can also be charged into a desired mold and post-polymerized.

[0015] Further, the raw material monomer composition may be UV-treated.
Additives such as absorbers, color inhibitors, and dye accelerators may also be added as necessary. Furthermore, various surface treatments can be performed after curing in order to improve the surface properties of the cured product.

[0016]

Effects of the Invention The optical resin of the present invention has a refractive index of 1.55 or more and a high Abbe number, has low optical distortion, and has excellent optical transparency, heat resistance, solvent resistance, and impact resistance. Moreover, it has a low specific gravity and can be made lightweight. In addition, there is no bad odor characteristic of sulfur compounds when charging and curing the raw monomer composition, and since the raw monomer composition has a low viscosity, it has excellent handling properties.
Since it is easy to control the reaction during curing and polymerization and to mold, it is useful as a resin material for plastic lenses such as eyeglass lenses, camera lenses, and optical materials, or for other optical applications.

[0017]

EXAMPLES The present invention will be explained in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[0018]

[Example 1] 10 g of the raw material monomer composition shown in Table 1,
0.05g tert-butyl peroxybenzoate
The mixture was added and mixed to obtain a monomer composition. Next, the monomer composition was placed in two glass molds, placed in a constant temperature bath at 80°C, heated at a curing temperature of 80°C for 6 hours, and further heated to 100°C for 3 hours. Then, it was heated at 100°C for 3 hours. Finally, an annealing treatment was performed at 100° C. for 2 hours to obtain a cured resin. The obtained cured resin was taken out from the mold, and its refractive index, Abbe's number, b* value, and heat resistance were measured according to the following methods. The results are shown in Table 1.

Refractive index and Abbe number: Measurements were carried out using an Abbe refractometer (manufactured by Atago Co., Ltd.) and a saturated methyl iodide solution as an intermediate solution.

b* value (yellowness): Measured using "Photometer Model 1001" manufactured by Nippon Denshoku Industries Co., Ltd. Note that the smaller this value is, the lower the degree of yellowness is, and the better.

Heat resistance: No deformation or discoloration after being placed in an oil bath at 130° C. for 1 hour was rated as ○, and those with deformation or discoloration were rated as ×.

[0022]

Examples 2 to 5 Cured resins were prepared in the same manner as in Example 1, except that the raw monomer compositions shown in Table 1 were used, and measurements were conducted for each. The results are shown in Table 1.

[0023]

[Table 1]

[0024]

[Comparative Examples 1 to 3] Cured resins were prepared in the same manner as in Example 1, except that the monomers shown in Table 2 were used, and measurements were conducted on each. The results are shown in Table 2.

[0025]

[Table 2]

Claims (1)

[Claims] Claim 1: Obtained by polymerizing and curing a raw material monomer composition containing as essential components (component A) a compound represented by the following general formula 1 and (component B) a compound represented by the following general formula 2. Optical resin. [Chemical formula 1] [Chemical formula 2]