Title:
TRANSPARENT RESIN AND ITS MANUFACTURE
Document Type and Number:
Japanese Patent JPH0220518
Kind Code:
A
Abstract:
PURPOSE:To prepare a transparent resin with a low photoelasticity coefficient, little warpage and deformation upon water absorption and high transparency by the polycondensation of raw materials for a polyester carbonate resin having a low C1 content and a specific structure in the presence of a catalyst comprising a lithium compd. CONSTITUTION:A polymer of the formula (wherein R1, R2, R5 and R6 are 8C or lower alkylene, alkylidene or cycloalkylene; a bond or a crosslinked structure of a 6C or lower alkylene or alkylidene group may exist to crosslink between R1 and R2 and between R5 and R6; there is no cas when both linkages of R1 to R2 and R5 to R6 are bonds at the same time; R3, R4, R7 and R8 are H, or 8C or lower alkyo; x and y are the copolymerization ratio, x:y=(99:1)-(1:99) is prepd. by polycondensation, while keeping the C1 content in the total raw materials below 200ppm and using a catalyst such as Li or LiH.
Inventors:
SASAKI SHIGERU
MATSUMOTO MITSUO
MATSUMOTO MITSUO
Application Number:
JP17145788A
Publication Date:
January 24, 1990
Filing Date:
July 08, 1988
Export Citation:
Assignee:
KURARAY CO
International Classes:
G02B1/04; C08G63/64; (IPC1-7): C08G63/64; G02B1/04
Attorney, Agent or Firm:
Honda Ken
Next Patent: FLUORINATED POLYETHER POLYESTER