JPH01101318A - Resin composition for eyeglass lens - Google Patents

Abstract

PURPOSE:To obtain the titled composition, containing a terminal acrylic-modified polybutadiene oligomer and a radically polymerizable vinyl monomer and capable of providing lightweight molded products having a high refractive index and Abbe's number and excellent heat resistance. CONSTITUTION:The aimed resin composition containing (A) 5-95pts.wt., prefer ably 5-60pts.wt. terminal acrylic-modified polybutadiene [e.g. expressed by the formula (R is H or CH3; X is phenyl, cyclohexyl, etc.)], (B) 95-5pts.wt., preferably 30-95pts.wt. radically polymerizable vinyl monomer [e.g. styrene or ethylene glycol (meth)acrylate]. Furthermore, 0.05-5pts.wt. radical polymeriza tion initiator is preferably blended with 100pts.wt. above-mentioned composition.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a resin composition for eyeglass lenses.

(Conventional technology) Conventionally, polycarbonate was used instead of inorganic glass.

Various studies and proposals have been made regarding the use of synthetic resins such as polystyrene for IIl mirror lenses. Among these, polycarbonate has the disadvantages of low surface hardness and easy orientation during molding, polystyrene has poor impact resistance, heat resistance, and machinability, and the one currently in practical use is diethylene glycol bisallyl. It is only a polymer whose main component is carbonate (hereinafter referred to as CR-39, CR-39 is a trade name of PPG Company, USA). CR-39 is lightweight and safe.

It has advantages that inorganic glass cannot satisfy, such as processability and dyeability, and since it is crosslinked, it also has good mechanical properties.

(Problems to be Solved by the Invention) However, CR-39 has a high curing shrinkage rate of 15%, and in order to improve the precision of curvature transfer from the glass mold and prevent lens distortion, CR-39 has a curing shrinkage rate of 15% per layer per hour. The drawback was that it required a long time (up to 20 hours).Therefore, in order to simultaneously meet the demands of many customers, a large number of glass molds were required, process control became complicated, and the manufacturing cost increased. In addition, the molding cycle was long, so it was not possible to quickly respond to the demands of mt customers. The object of the present invention is to provide a resin composition for eyeglass lenses that can be molded.

(Means for Solving the Problems) The present invention provides a resin for eyeglass lenses containing as main components 5 to 95 parts by weight of an acrylic-terminated polybutadiene oligomer and 5 to 95 parts by weight of a radically polymerizable polymerizable vinyl monomer. It is a composition.

This resin composition can be polymerized in a single hour, and the properties of the cured product are equivalent to or higher than those of CR-39.

Typical terminal-acrylic-modified polyptadiene oligomers include compounds represented by the following formulas T1) to (4).

(Left below) General formula +1l -Czlla-0-nee N-X-nee! -0-CJa-
0-knee:=Cl1z (in the formula R4; Ell also hacl1
) ヲ,
, represents. ) General formula 2) -Mount C-Oj! -N-X-j knee! -0-Mount C-04-
C=CHt (in the formula, R&;!H or HACHs wo, In (1) to (4), n≧25.

It is preferable that M is -1,000 to 3,000. However, it is preferable that the resin composition exhibits fluidity to the extent that it can be poured into a glass mold. , = 1,000 to 3,000.

It is preferable to perform the injection at room temperature, but heating may also be used.

The vinyl monomer that can radically co-form with the tagene oligomer in the terminal acrylic-modified polyester may be any known vinyl monomer, preferably one that is a low viscosity liquid at room temperature, has a high boiling point, and is as colorless and transparent as possible. good.

Examples include styrene, styrene derivatives such as chlorostyrene, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate,! ,
3 Methanediol (meth)acrylate, isobornyl methacrylate, neopentyl glycol dimethacrylate.

Tetraethylene glycol methacrylate, l.

6-hexanediol di(meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxytyryl (meth)acrylate.

Examples include acrylic esters and methacrylic esters such as tricyclodecanyl (meth)acrylate and dipentaerythritol hexaacrylate.゛.

In the resin composition of the present invention, if the terminal acrylic-modified polybutadiene oligomer is too large, the viscosity of the resin composition becomes high, making casting work difficult.

On the other hand, if the terminal acrylic-modified polybutadiene oligomer is small, that is, the polymerizable and nil monomer is large, the hexapolymer will be bent and the strain will be large. Therefore, the terminal acrylic-modified polybutadiene oligomer is 5 to 95 parts by weight, preferably 5 to 60 parts by weight, 95 parts by weight of the polymerizable vinyl monomer.
Parts by weight, preferably 30 to 95 parts by weight.

In addition, the resin composition of the present invention may contain 0.0% ultraviolet absorber in order to improve its weather resistance and light resistance, if necessary.
Preferably, 3 to 3.0 parts by weight are added. When adding an ultraviolet absorber, if it is less than 0.03 parts by weight, it will have almost no effect, and if it exceeds 3.0 parts by weight, it will turn yellow and its commercial value will decrease.

Benzotriazole type UV absorbers.

In addition to hensifenones, salicylic acids, and cyanoacrylates, hindered amines and N as UV stabilizers
A wide variety of salts such as i-complex salts and benzoate salts can be used.

Additionally, antioxidants, anti-yellowing agents, and internal mold release agents.

It is also possible to add so-called additives such as antistatic agents and leveling agents.

The resin composition of the present invention is preferably polymerized by a method of injecting the resin composition into a mold held by an elastomer gasket or spacer and heating it, but other known polymerization methods 1 such as reaction injection molding ( RIM).

Polymerization can also be carried out by photopolymerization or radiation polymerization.

Benzoyl peroxide is used as a polymerization initiator.

Organic peroxides such as isopropyl peroxydicarbonate and lauroyl peroxide, or azo compounds such as azobisisobutyronitrile are used. The type and amount of the polymerization initiator are determined by the composition 1 reactivity 5 of the resin composition. The amount is determined in consideration of reaction rate control, etc., but is usually mixed in an amount of 0.05 to 5 parts by weight per 100 parts by weight of the resin composition.

Polymerization conditions are 60°C to 160°C for 0.5 to 5 hours (
, most preferably at 80°C to 140°C for 2 to 4 hours; if the temperature is outside this range, curing may be insufficient.
It will turn yellow and you will not be able to get the desired effect.

(Example) A mold having a cavity with a center thickness of 2 wa and a ridge thickness of 5 wa, which was composed of a glass mold with a diameter of 100 mm and a silicone gasket, was prepared, and 1 part by weight of Parhexa 3M ( Various resin compositions of Table 1 1) kl-Na5 were added and mixed with organic peroxide (manufactured by NOF ■),
After maintaining the temperature at 100° C. during summer time using a hot air circulation dryer, it was further heat-cured at 140° C. for 2 hours. Thereafter, the molded body was taken out from the mold and various physical properties were measured. The measurement results are shown in Table 1.

Various physical properties were measured by the following methods.

(1) Refractive index (nD'') The refractive index at 20° C. was measured using an Atsube refractometer. I also asked for the loss of 7 games. Monobromonaphthalin was used as a contact liquid.

(2) Light transmittance (Tt%) The light transmittance of a polymer having a thickness of 2 mm at a wavelength of 580 mm was measured using an ultraviolet spectrophotometer.

(3) Surface hardness The pencil hardness was determined.

(4) Density (g/csi) It was measured by the pyranometer method.

(5) Heat-resistant temperature (’C) The glass transition temperature was determined by the DSC method.

(6) Conforms to impact resistance FDA standards and has a height of 127 mm in a molded body with a thickness of 2 fi.
A 16g steel ball was dropped from a specimen and examined.

Those that are broken are indicated by ×, and those that are not broken are indicated by 0.

(7) Machinability When cut with a grinder, a sample that was cut cleanly without cracking is indicated by ○, a sample that does not crack but some cutting powder remains is Δ, and a sample with cracks or cutting powder that remains firmly is indicated by ×.

Comparative Example CR-39 was molded into the same shape as the example, and various physical properties were measured in the same manner. The results are also shown in Table 1.

(Margin below) (Effect of the invention)

Claims (2)

[Claims] (1) A resin composition for eyeglass lenses containing 5 to 95 parts by weight of a terminally acrylic-modified polybutadiene oligomer and 95 to 5 parts by weight of a polymerizable vinyl monomer capable of radical polymerization as main components. (2) The resin composition for eyeglass lenses according to claim 1, wherein 0.05 to 5 parts by weight of a radical polymerization initiator is mixed with 100 parts by weight of the main component.