JPH04202512A - Production of thermoplastic resin and lens having high refraction index - Google Patents

Abstract

PURPOSE:To obtain the title resin useful as a material for lens of glasses and other optical lenses, having excellent heat resistance, dyeability and transparency by polymerizing styrene with acrylonitrile and tricyclodecyl methacrylate in a specific ratio. CONSTITUTION:35-70wt.%, preferably 40-60wt.% styrene is polymerized with 10-25wt.%, preferably 15-20wt.% acrylonitrile and 10-40wt.% (100wt.% total amount) methacrylic acid tricyclo[5,2,1,0<2.6>]dec-8-yl to give the objective resin having >=1.53 refractive index, >=35 Abbe's number and excellent dyeability of lens. The polymerization is carried out by suspension polymerization and polymerization temperature is preferably raised from 65-80 deg.C by stages.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a thermoplastic material that has excellent heat resistance, dyeability, and good transparency and can be used as a material for eyeglass lenses and other optical lenses. This invention relates to a resin manufacturing method and a high refractive lens.

[Conventional technology] Conventionally, materials for optical lenses include highly transparent acrylic resin, diethylene glycol bisallyl carbonate resin,
Polystyrene, polycarbonate, etc. are used, but among these, the one that is widely used for eyeglass lenses is
This lens uses thermosetting resin diethyl chloride bisallyl carbonate. The reason is that it has excellent heat resistance, impact resistance, and dyeability. It also has excellent cutting properties when processing into a desired shape.

[Problems to be Solved by the Invention] A lens using Shikashiwa diethylene glycol bisallyl carbonate has a refractive index of 1.5.

The drawback is that the lens is thicker than a glass lens (this is especially noticeable when the lens variable becomes large).

Recently, there has been a growing desire for eyeglass lenses to be thinner and lighter, and there has been a need for materials for eyeglass lenses that have a high refractive index to make this possible.

Lenses using polystyrene (refractive index L6, Abbe number 30) or polycarbonate (refractive index L58, Abbe number 30) have a high refractive index.

Chromatic aberration is large due to the small Atsube number.

The dyeability is poor, and the former also has poor heat resistance.

On the other hand, if you think about how lenses are manufactured.

Since acrylic resin, polystyrene, and polycarbonate are thermoplastic, they can be injection molded and mass produced easily, whereas diethylene glycol bisallyl carbonate is thermosetting and can only be made by casting. , unsuitable for mass production.

This development has been developed based on the above points, and has excellent heat resistance and dyeability.
Another object of the present invention is to provide a method for producing a thermoplastic resin that can be used for injection moldable spectacle lenses and other optical lens materials, and to provide a high refractive lens.

[Means for Solving the Problems] The present invention provides 35 to 70 weight X of styrene, 10 to 25 weight X of acrylonitrile, and tricyclo methacrylate [5,
A method for producing a thermoplastic resin characterized by polymerizing 10 to 40% by weight of 1.02-dec-8-yl [100% by weight in total], and a thermoplastic resin using the thermoplastic resin obtained by the method. Regarding refractive lenses.

It is preferable that the thermoplastic resin has a refractive index of L53 or more, an Atsube number of 35 or more, and good lens dyeability.

The amount of methacrylic acid tricyclo[5,Z 1.0 '']decar 8-i used is in the range of 10 to 40% by weight.

If it is less than 10% by weight, the effect of improving heat resistance is small.

If it exceeds 401t%, tricyclo[5,2 methacrylate]
, LO"]] Decal 8-i remains as an unreacted monomer. The amount of acrylonitrile used is 10 to 2.
The range is 5% by weight. The Fil content is preferably in the range of 5 to 20% by weight. If it is less than 10% by weight, transparency and dyeability will decrease. If it exceeds 25% by weight, the resin will be colored. The amount of styrene used is in the range of 35 to 70% by weight. A range of 40 to 60% by weight is preferred. If it is less than 35% by weight, the refractive index will decrease, and if it exceeds 70% by weight, the number of pimples will decrease and the dyeability will decrease.

Known polymerization methods can be used to produce the thermoplastic resin in the present invention.

Suspension polymerization is preferred. The bulk polymerization method requires a special reactor, making reaction control complicated. The solution polymerization method has the same drawbacks as the bulk polymerization method and has poor productivity. Emulsion polymerization requires a large amount of emulsifier, which reduces transparency.

Initiators 1 used in polymerization include 9, for example, benzoyl peroxide, lauroyl peroxide, di-t-butylperoxyhexahydroterephthalate, t-butylperoxy-2
-Ethylhexanoate, organic peroxides such as Ll-di-t-butylperoxy-λ&5-trimethylcyclohexane, azobisisobutyronitrile, azobis-4-
Azo compounds such as methoxy-2,4-dimethylvaleronitrile, azobiscyclohexanone-1-carbonitrile, azodibenzoyl, water-soluble catalysts such as potassium persulfate, ammonium persulfate, and peroxides or persulfates and reducing agents. Any combination of redox catalytic forces that can be used for normal radical polymerization is possible. The polymerization catalyst is preferably used in an amount of 0.01 to 1.0% by weight of the monomer mixture. It is also possible to use two or more components. As the chain transfer agent, mercaptan compounds, thioglycol, carbon tetrachloride, α-methylstyrene dimer, etc. can be used, but it is preferable to use mercaptan compounds in view of the overall physical properties of the nine polymer.

In suspension polymerization, care must be taken when adjusting the polymerization temperature because the polymerization temperature is a three-component system and the reaction rates are considerably different. It is preferable that the temperature of this polymerization part V is raised stepwise from 65°C to 80°C (normally the temperature is raised to Fi 100°C). 65℃
It is more preferable to raise the temperature in stages from When starting the stepwise temperature increase from a temperature below 65°C, 9 the polymerization time becomes longer;
Productivity tends to decline. If the stepwise temperature increase is started from a temperature exceeding 80° C., since the temperature is above the boiling point of acrylonitrile, the acrylonitrile becomes a gas phase and comes out of the reaction system, so that it may not be able to participate in copolymerization.

Suspension polymerization is carried out in an aqueous medium and a suspending agent is added. ! Examples of drying agents that can be used include water-soluble polymers such as polyvinyl alcohol, methylcellulose, polyacrylamide, and poly(meth)acrylates, and sparingly soluble inorganic substances such as calcium phosphate and magnesium pyrophosphate.

From the viewpoint of transparency, it is preferable to use poly(meth)acrylate as a suspending agent. Further, it is preferable to use the suspending agent in an amount of 0.03 to 1.0% by weight of the monomer mixture.

Poly(meth)acrylate, which is a water-soluble polymer, can be produced, for example, as follows. Namely.

Hydroxyalkyl (meth)acrylates, salts of (meth)acrylic acid (lithium salt, sodium salt.

(potassium salt, magnesium salt, calcium salt, ammonium salt, etc.), (meth)acrylic salt, and if necessary, other unsaturated monomers that can be copolymerized with these other than these to form a water-soluble polymer. (Meth)acrylate can be produced.

The molecular weight of the thermoplastic resin obtained by the present invention is not particularly limited.

From heat resistance 9 Mechanical properties discussion 9 Weight average molecular weight (polystyrene equivalent) IQ, 000 to L, 00 to 000 books are preferred, especially books in this range.

Preferred when used as a molding material.

When using the Soba Shin Shiho Toku Netsucho plastic resin obtained by the present invention, from the viewpoint of prevention of deterioration, thermal stability, moldability, processability, etc. oxidizing agents, aliphatic alcohols,
Mold release agents such as fatty esters, phthalate esters, triglycerides, fluorine surfactants, high-grade fatty metal salts, other lubricants, plasticizers, antistatic agents, ultraviolet absorbers, flame retardants, double metal deactivators etc. may be added and used.

[Example] The present invention will be explained below with reference to Examples.

Suspending agent: Synthesis of water-soluble polymer ■ (polymethacrylic salt)> Methyl methacrylate 59 + 2-hydroxyethyl methacrylate 12 g, potassium methacrylate 239 and deionized water 360 g were placed in a separable flask with an internal volume of 500 d. After removing the air in the system by blowing N2 gas for 30 minutes, the system was heated to 65°C while heating and stirring in a water bath, and potassium persulfate was 0.0
69 was added. Polymerization was carried out at the same temperature for 5 hours, followed by 9
Raise the temperature to 0℃ and continue stirring for 2 hours to produce a jelly-like water-soluble polymer■.

Example 1 Tricyclo[s,zLo”1deca-8-(
(TCDMA) 280 g, methylene (BT) 98
0g, 7crylonitrile 1N) 1409° lauroyl barogicide (9.8g), t-butyl peroxy 2-ethylhexanoate Z8s and n-octyl mercaptan (1.4g) were mixed and dissolved to obtain a seven-mer solution.

In a 51 separable flask equipped with a stirrer and a condenser, the above-mentioned jelly-like water-soluble polymer o, 7 was added as a suspending agent.
g, and 1960 g of deionized water were added and stirred to obtain a suspension medium. The following composition was added to this while stirring, and the stirring rotation speed was 28 Orpm at 65°C for 4 hours under a nitrogen atmosphere at 80°C.
Polymerization was then carried out at 100°C for 2 hours (polymerization rate 9
9% (by weight). The synthesized polymer particles are washed with water, dehydrated,
Dry. Next, the polymer particles are injection molded, and the resulting molded product has light transmittance, refractive index, Atsube number, and glass transition temperature (
Measures of heat resistance), dyeability, etc. were investigated.

Characteristic evaluation was based on the following method.

- Light transmittance: Measured according to ASTM D1003.

-Refractive index, Atsbe number: Measured using an Atsbe refractometer (manufactured by Atago Corporation).

- After dissolving the glass transition temperature double polymer in methylene chloride, it was poured into methanol with stirring to precipitate the double polymer, which was then filtered and dried to obtain a white powdery polymer. Differential set meal calorimeter (DEC: PerkinElmer D) using this
The glass transition saturation degree (Tg) was measured using a method (SC-7 type).

・Dyeability: Sumikalon Blue EBL (Sumitomo Chemical ■
A dye bath was prepared by dissolving 29 (manufactured by Mimaki Co., Ltd.) in 1000% pure water. The molded product was immersed in the dye bath heated to 80° C. for 30 minutes, washed with water, and then observed for dyeability.

Examples 2 to 5 Molded articles were prepared in the same manner as in Example 1, except that the compositions (wt%) of styrene, acrylonitrile, and methacrylic acid ester were varied, and their physical properties were evaluated.

Comparison examples 1 to 4 Monomer mixture without methacrylate esters.

A molded article was prepared in the same manner as in Example 1 except that a monomer mixture containing no acrylonitrile and a three-component composition (wt%) was used, and its physical properties were evaluated.

Examples 6 and 7 Composition of styrene, acrylonitrile, and methacrylic acid ester A molded article was prepared in the same manner as Fi Example N4, and its physical properties were evaluated.

Table 1 Margin below Table 2 s'rc; Styrene ACN; Acrylonitrile TCDMA; Methacrylic acid t') '/ Ria [5
，! More than 1.0163 Dec-8-yl! Margin m - Table 3 [Effects of the Invention] The thermoplastic resin obtained by the present invention is heat resistant.

It has excellent transparency and dyeability, and is extremely useful as a high refractive lens such as eyeglass lenses and other optical lenses.

Agent Patent Attorney Kuni Wakabayashi i

Claims (1)

[Claims] 1. Styrene 35-70% by weight, acrylonitrile 10
~25% by weight and tricyclo[5,2,1
,0^2^. ^6] Dec-8-yl 10-40% by weight [
A method for producing a thermoplastic resin, comprising polymerizing a total amount of 100% by weight. 2. The method for producing a thermoplastic resin according to claim 1, which has a refractive index of 1.53 or more, an Atsube's number of 35 or more, and good lens dyeability. 3. Polymerization was carried out by suspension polymerization at a polymerization temperature of 65°C to 80°C.
4. The method for producing a thermoplastic resin according to claim 1, 2 or 3, wherein the temperature is raised stepwise from a temperature of .degree. 4. A high refractive lens made of a thermoplastic resin obtained by the manufacturing method according to claim 1, 2 or 3.