Process for producing prepreg
CA 2069601 C · Owner: Yazawa, Hiroshi · Inventors: Iwanami, Yoshimu; Yazawa, Hiroshi; Yoshida, Sumio
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides a prepreg obtained by stretching a material comprising, as a main component an, ultra-high-molecular-weight polyethylene having an intrinsic viscosity of 5-50 dl/g as measured at 135°C in decalin to a, total draw ratio of at least 20, subjecting the resulting stretched polyethylene material to a splitting treatment and, impregnating the resulting material with a thermosetting resin, and a process for producing said prepreg. The split stretched polyethylene material has improved adhesion to the impregnant resin and can be used as a good base material for prepreg.
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
- Filed May 26, 1992 and granted April 21, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 26, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 26, 2014.
- 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.