JPS63170404A - Resin component having high refractive index - Google Patents

Abstract

PURPOSE:To obtain a composition having high refractive index, excellent surface properties, surface hardness, impact resistance and processing properties required as optical lens and low water vapor absorption, by polymerizing specific amounts of two kinds of polymers, tribromophenyl methacrylate and p- chlorostyrene. CONSTITUTION:(A) 10-60wt.% monomer shown by formula I (m and n are 0-4; X is H or halogen except F; a is 0-2; R1 and R2 are H or CH3; R3 is CH3-C-CH3, SO2 or S), (B) 2-30wt.% monomer shown by formula III (m is 1-23; p is 2-12; R1 is H or CH3), (C) 25-70wt.% tribromophenyl methacrylate and (D) 5-50wt.% p-chlorostyrene (A+B+C+D=100) are polymerized as main components to give the aimed composition having >=1.60 refractive index. The composition is especially useful as a plastic lens for glasses.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is directed to a resin composition having a refractive index of 1.60 or more among the various physical properties required for a plastic lens, especially a plastic lens for eyeglasses, and furthermore, transparency. It is used as a high refractive index resin composition for use in plastic lenses, which has excellent surface hardness, impact resistance, processability, etc., and is easy to mold.

[Conventional technology]

Conventionally, various studies and proposals have been made regarding synthetic resins to replace inorganic glass. For example, a polymer whose main component is diethylene glycol bisallyl carbonate (hereinafter abbreviated as CR-39) has been put into practical use as an optical lens. Plastic lenses are generally lighter than glass lenses, have higher impact resistance, can be dyed, do not require polishing, and can be mass-produced because they can be easily molded from the material. .

[Problems to be solved by the invention] However, since CR-39 has a lower refractive index of 1.50 than ordinary glass, the edge thickness of the negative lens is lower than that of the positive lens. This also has the disadvantage that the center thickness of the lens becomes large.

On the other hand, attempts have been made widely to obtain high refractive index plastic lenses using high refractive index monomers that have improved these drawbacks. For example, 2,2-bis(3,5-dibromo,4-methacryloyloxyethoxyphenyl)propane and P-chlorostyrene, which are found in JP-A-59-184210, are very effective in increasing the refractive index of resins. However, if only these monomers are used, the impact resistance required for plastic lenses is insufficient. Therefore, polymerizable monomers other than the above monomers have also been proposed;
There are almost no lenses that satisfy high refractive index and impact resistance and have good lens moldability by cast polymerization, and 2,2-bis(3,5-dibromo).

Regarding 4-methacryloyloxyethoxyphenyl)propane, as the proportion of it contained in the monomer mixture increases, the viscosity of the mixture increases.For example, when performing cast polymerization, which is a common eyeglass lens molding method, Practical problems also arise, such as difficulty in injecting the mixed liquid into a glass mold and defoaming after injection. Furthermore, the above P-
Chlorostyrene may also have drawbacks such as the fact that the polymer obtained by polymerization becomes cloudy when the proportion of chlorostyrene increases. Also, JP-A-59-13631
Tribromophenyl methacrylate, which is found in grade 1, is very effective in increasing the refractive index of resins, but since it itself is a solid, it cannot be used, for example, when performing cast polymerization, which is a common eyeglass lens molding method. , it is necessary to dissolve it in another polymerizable liquid monomer or to melt the monomer itself. However, as the proportion of tribromophenyl methacrylate in the monomer mixture increases, tribromophenyl methacrylate often precipitates from the once homogeneous mixture. This poses a practical problem, such as the need to heat-dissolve or melt tribromophenyl methacrylate to form a uniform liquid mixture when making lenses.

[Means to solve the problem]

The present inventors have completed the present invention as a result of intensive research aimed at improving these drawbacks of conventional resins. The present inventor has proposed the following method: (A) at least one first monomer selected from the group of monomers represented by general formula (1); and (C) tribromophenyl methacrylate (third monomer). ) was found to be able to suppress the precipitation of the third monomer from the monomer mixture by using them together in a specific ratio, and in addition to these, (B) a unit represented by the general formula (2) or (3) below was added. at least one type of second monomer selected from the group of monomers and (D) p-chlorostyrene (fourth monomer)
By mixing them in a specific ratio, for example, the mixture has a viscosity suitable for injection into a glass mold when performing cast polymerization, which is a common eyeglass lens molding method, and solids from a homogeneous mixture can be obtained. When monomer precipitation is suppressed, lens creation is facilitated, and the mixture is subjected to radical polymerization (
A) General formula (1) General formula (2) % formula % General formula (3) R+ R+ J (In the formula, m represents an integer of 1 to 23, p represents an integer of 2 to 12, R1 is H or CH3) was found to have a refractive index of 1.60 or more.

In the present invention, the lens can be easily molded, the refractive index of the polymer obtained by radical polymerization is 1.60 or more, impact resistance,
The present invention provides a novel resin for plastic lenses that has excellent processability and high surface hardness.

The present invention will be explained in detail below.

The present invention comprises (A) at least one type of first monomer selected from the group of monomers represented by general formula (1), and (B) a first monomer represented by general formula (2) or (3). at least one type of second monomer selected from the group of monomers (C
) A high refractive index resin composition obtained by polymerizing a monomer mixed solution consisting of tribromophenyl methacrylate and (D) p-chlorostyrene in a specific ratio in the presence of a radical polymerization initiator. In the present invention, the above (A
) The total content of the first monomers is preferably 10 to 60% by weight, preferably 20 to 50% by weight. (A) The higher the content of the first monomer, the better the refractive index, impact resistance, heat resistance, solvent resistance, and flame retardance of the polymer obtained by polymerization. If the content of the polymer is less than 10i% by weight, the above-mentioned physical properties deteriorate and the object of the present invention cannot be achieved. On the other hand, if the content of the first monomer (A) exceeds 60% by weight, the viscosity of the monomer mixture solution becomes extremely high, and for example, when performing cast polymerization, which is a common eyeglass lens molding method, a glass mold is used.・Injecting the mixed liquid and defoaming after injection becomes difficult. The total content of the second monomer (B) is 2 to 30% by weight, preferably 5 to 2% by weight.
0% by weight is preferred.

(B) When the content of the second monomer is 2il%,
The impact resistance of the polymer obtained by polymerization is insufficient, and if it exceeds 30% by weight, the refractive index and heat resistance of the resin composition obtained by polymerization decrease.

The content of the third monomer (C) above is 25 to 70% by weight,
Preferably 35 to 60% by weight is suitable.

(C) The higher the content of the third monomer, the better the refractive index, hardness, heat resistance, hygroscopicity, and flame retardance of the polymer obtained by polymerization. If the content is 25% ungrooved, the refractive index decreases and the object of the present invention cannot be achieved. On the other hand, the content of the third monomer (C) is 70
If it exceeds % by weight, the third monomer (C), which is uniformly dissolved in the monomer mixture, will precipitate in an increased amount, resulting in a decrease in the workability of making lenses. The content of the fourth monomer (D) is 6
~50% by weight, preferably 8-40% by weight is suitable. (D) When the content of the fourth monomer is 5% by weight, the viscosity of the monomer mixture solution becomes significantly high, and for example,
When performing cast polymerization, which is a common eyeglass lens molding method, it becomes difficult to inject the mixed solution into a glass mold and to defoam after injection, and the refractive index of the resin composition obtained by polymerization decreases. On the other hand, 40! When the amount exceeds %, the viscosity of the monomer mixed solution becomes extremely low, leakage from the glass mold occurs, and the yield of lens molding decreases. Furthermore, the resin composition obtained by polymerization becomes cloudy, or the resin tends to be partially peeled off from the glass mold, resulting in deterioration of the surface properties of the lens. Here (A)-(D)
The total weight of the components is 100%.

The following components may be added as other components (fifth component) to the first to fourth components described above.

b) Substances represented by general formula (4), such as diallylisophthalate (b) Benzyl methacrylate represented by formula (5) (c) Substances represented by general formula (6) (where m is 1) or 2, a represents 2.3 or 6, and b represents 0.3 or 4) (d) Substance represented by general formula (7) (in the formula, m and n
The sum of is 2 or 4. ) These (a) - (d)
These components can be contained in a total amount of at most 30% by weight based on the total of components (A) to (D).

The polymerization method of the resin composition of the present invention is not particularly limited, and any known polymerization method can be employed. For example, the composition can be produced by heating the mixed solution in the presence of a polymerization initiator between molds held by gaskets or spacers, but the composition can also be produced by photopolymerization or radiation polymerization. be able to. Further, by selecting the type and amount of the polymerization initiator, it is possible to manufacture by a reaction injection molding method (RIM), and the manufacturing method is not limited thereto.

The polymerization amount initiator used here is not particularly limited, and known ones can be used. Examples of the polymerization initiator used during thermal curing include t-butylperoxyisopropyl carbonate, cumylperoxyoctoate,
Peroxy esters such as t-butyl peroxyisobutyrate, t-butyl peroxy bivalate, t-butyl peroxy (2-ethylhexanoate), diisopropyl peroxy dicarbonate, similystyl peroxy dicarbonate, etc. Peroxydicarbonate milk Diacyl peroxides such as benzoyl peroxide, 3,3゜5-trimethylhexanoyl peroxide, and isobutyryl peroxide; dialkyl peroxides such as dicumyl peroxide and di-t-butyl peroxide. , hydroperoxide necks such as diisopropylbenzene hydroperoxide and t-butyl hydroperoxide, peroxyketals such as 1,1-bis(1-butylperoxy)cyclohexane, ketones such as cyclohexanone peroxide, and methyl ethyl ketone peroxide. Examples include peroxides, other peroxides, and azo compounds such as azobisisobutyronitrile. Further, when curing with ultraviolet rays, examples of initiators include benzoin isopropyl ether, benzophenone, benzoin isobutyl ether, acetophenone, and the like. The amount of the polymerization initiator is usually 0.0 based on the monomer.
01 to 10% by weight, preferably 0.01 to 5% by weight. The type and concentration of the polymerization initiator used are determined in consideration of the composition of the monomer mixture, reactivity, reaction rate control, etc.

In addition, the resin composition of the present invention may contain an ultraviolet absorber of 0.03 to 0.03 to improve its light resistance and weather resistance, if necessary.
It is desirable to contain 3.0 parts by weight. If the concentration of the ultraviolet absorber is less than 0.01% by weight, the light resistance will be extremely low.
It has almost no effect on improving weather resistance, and if it exceeds 3.0% by weight, yellow coloring becomes noticeable and the commercial value tends to decrease.

The UV absorbers used in the present invention include a wide range of UV absorbers such as benzotriazole, benzophenone, salicylic acid, and cyanoacrylate, as well as hindered amine, Ni complex salt, and benzoate as UV stabilizers.

Furthermore, during polymerization, mold release agents, antioxidants,
It may contain additives such as antistatic agents and various stabilizers, and bluing agents.

Furthermore, the resin molded article of the present invention may be coated on its surface in order to improve its optical or mechanical stability.

[Effect]

The resin composition obtained by the present invention not only has a higher refractive index than CR-39, but also has excellent surface properties, surface hardness, impact resistance, and processability necessary for optical lenses, and has low hygroscopicity. It is extremely excellent as a material.

The above-mentioned optical materials include so-called lenses for still cameras, video cameras, telescopes, and sunlight concentrators, prisms, disks such as video disks and audio disks, and mirrors such as concave mirrors, convex mirrors, and polygons. Examples include optical fibers, optical fibers, and optical conductive elements such as optical waveguides.

〔Example〕

Next, the present invention will be described in detail, but the present invention is not limited thereto.The test methods for each characteristic were performed as follows.

Refractive index and Atsbe number: Measured using an Atsbe refractometer.

Impact resistance: FDA approved for concave lens with center thickness of 2 mm
A steel ball drop test was conducted in accordance with the standard, and those with no cracks were rated excellent (○), those with slight cracks were rated good (Δ), and those with cracks were rated poor (X).

Hardness: Measured by pencil hardness.

Example 1 2.2-bis(3,5-dibromo,4-methacryloyloxyethoxyphenyl)propane 40 parts by weight, n=1
4 polyethylene glycol dimethacrylate) 10 parts by weight, tribromophenyl methacrylate 40! quantity,
10 parts by weight of parachlorostyrene, 2 parts by weight as an ultraviolet absorber
1 part by weight of -(2'-hydroxy-3',5'-ditertiary-butylphenyl)-5-chlorobenzotriazole and 2 parts by weight of t-butylperoxy(2-ethylhexanoate) as a radical polymerization initiator. The mixed solution consisting of 50% was poured into a mold assembled with a glass mold and a gasket made of ethylene-vinyl acetate copolymer, and heated from 35°C to 80°C over 20 hours. The lens was removed from the glass mold and post-cured at 100°C for 2 hours. The obtained lens had a refractive index of 1,601 and an Atsbe's number of 32.8, and showed excellent physical properties such as impact resistance, abrasive workability, and light resistance, making it an excellent result as an optical resin. showed that.

Examples 2 to 17 Polymerization was carried out in exactly the same manner as in Example 1 to obtain colorless and transparent lenses of various compositions. The results are shown in Table 1.

Monomer abbreviation era(EtO)2BPMA: 2.2-bis(3,
5-dibromo,4-methacryloyloxyethoxyphenyl)propaneBr4(EtO)2BPsA: bis(3,5-dibromo,4-acryloyloxyethoxyphenyl)sulfoneBra(EtO)2Ph2SA: bis(3,5-
Jibromo.

4-Acryloyloxyethoxyphenyl) sulfide PEDM (m>: polyethylene glycol dimethacrylate) (n=m) NDA: 1. 9-nonanediol diacrylate 0AIP Nidialylisophthalate Br3
PhMA: ) Ribromophenyl methacrylate PC5T: Barrachlorostyrene 8DA
:L 4-butanediol diacrylate BzMA :benzyl methacrylate) ID
A: 1,6-hexanediol diacrylate Brn8PM^: 2,2-bis(3,5-dibromo,4-methacryloyloxyphenyl)propane TEGDM: ) lyethylene glycol dimethacrylate 0r4Ph, SA: 2. 2-bis(3,5
-dibromo, 4-acryloyloxyphenyl) sulfide DPCA-20 In general formula (6), m = 1°a =
2. b = 4 HX-220 m+n=2 in general formula (7)

Claims (1)

[Claims] (1) 10 to 60% by weight of a first monomer represented by the following (A) general formula (1) and a second monomer represented by the following (B) general formula (2) or (3) 2 to 30% by weight and (
C) 25 to 70% by weight of tribromophenyl methacrylate and (D) 5 to 50% by weight of p-chlorostyrene (total of the above 100% by weight) are polymerized as main components,
A high refractive index resin composition having a refractive index of at least 1.60. (A) General formula (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ・・・・・・・(1) (In the formula, m and n each independently represent an integer from 0 to 4, and
represents H or a halogen other than fluorine, a represents an integer from 0 to 2, R_1 and R_2 represent H or CH_3, and R_3 represents CH_3-C-CH_3, -SO_2- or -S-) (B) General formula (2) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(2) General formula (3) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(3) (In the formula, m is an integer from 1 to 23 , p represents an integer from 2 to 12, R_1 represents H or CH_3)