Claims
- 1. A process for producing an optical resin which comprises subjecting a monomer mixture comprising
- (a) 97 to 50% by weight of methyl methacrylate,
- (b) 3 to 30% by weight of an N-substituted maleimide, and
- (c) 0 to 40% by weight of an unsaturated monomer other than methyl methacrylate and the N-substituted maleimide and copolymerizable therewith, a total weight of monomers being 100% by weight, to suspension polymerization in the presence of poly(meth)acrylic acid salt as a suspending agent while maintaining a pH of 5.5 to 7.5 by adding a buffering agent thereto.
- 2. A process according to claim 1, wherein the pH is maintained at 6.0 to 7.0.
- 3. A process according to claim 1, wherein the monomer (c) is selected from the group consisting of cyclohexyl methacrylate, norbornyl methacrylate and tricyclo[5,2,1,0.sup.2.6 ]deca-8-yl methacrylate.
- 4. A process according to claim 1, wherein the suspension polymerization is at a temperature of from 0.degree. to 200.degree. C.
Priority Claims (1)
Number |
Date |
Country |
Kind |
63-222696 |
Sep 1988 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 403,387 filed Sep. 6, 1989, now abandoned.
US Referenced Citations (3)
Continuations (1)
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Number |
Date |
Country |
Parent |
403387 |
Sep 1989 |
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