Polyester sheet containing antiblock agent added in degradable polycarbonate
CA 1104314 A · Owner: Allied Chemical Corporation · Inventors: Walacavage, Eugene V.; Bollen, Philip S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A polyester sheet containing an antiblock agent is produced by uniformly blending a small amount of a degraded polycarbonate containing the antiblock agent. The antiblock agent must have an inherent or adjusted pH of less than six to degrade the polycarbonate to lower its molecular weight upon extrusion compounding. This in turn makes a uniform blend and resulting clear sheet with antiblocking properties. In another embodiment, larger amounts of polycarbonate containing the antiblock agent are used.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted July 7, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 7, 1998.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.