Acrylic flexible light pipe of improved photo-thermal stability,申请号EP19970309822-传众专利搜索

Acrylic flexible light pipe of improved photo-thermal stability

申请公布号：EP0849315(A1)

申请号：EP19970309822

申请日期：1997.12.05

申请公布日期：1998.06.24

申请人：

ROHM AND HAAS COMPANY

发明人：ILENDA, CASMIR STANISLAUS;JOHNSON, PHELPS BRIAN;HALLDEN-ABBERTON, MICHAEL PAUL

分类号：G02B6/00;B29C47/00;B29D11/00;B29K33/04;C08J9/34;C08K5/00;C08L33/08;G02B1/04;G02B6/02;(IPC1-7):C08K5/00;B29B11/14;C08L33/06;C08L43/04

主分类号：G02B6/00

摘要：<p>Acrylic light pipe has adequate thermal and photo-thermal stability for many purposes, but is deficient in maintaining clarity, color, and good optical properties under conditions of exposure to high temperatures, especially in combination with exposure for lengthy periods to passage of light. Improved thermal stability, as reflected in reduced color formation, can be imparted by adjusting the polymerization conditions to produce the uncured core polymer of the core/clad construction with a much reduced terminal vinyl content, preferably below 0.5 vinyl groups/ 1000 monomer units. This process improvement, in combination with selected addition of a combination of certain hindered phenols and hydrolytically stable organic phosphites, together produce a substantial improvement in the resistance to discoloration under photo-thermal conditions, while maintaining the resistance to discoloration under thermal conditions. The known process conditions which do not yield lower terminal vinyl content, in combination with the selected additives, also produce acrylic light pipe with greatly improved photo-thermal stability.</p>