Process for producing porous thermoplastic resin sheet
CA 1048723 A · Owner: Sumitomo Chemical Company · Inventors: Tsuji, Kozo; Matsunaga, Hiroomi; Watanabe, Masashi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A porous thermoplastic resin sheet is obtained by molding into a sheet a mixture comprising 100 parts by weight of a thermoplastic resin and 0.1 to 50 parts by weight of a pullulan powder, and then immersing the resulting thermoplastic resin sheet in water to dissolve-out and remove the said pullulan powder.
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 February 20, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 20, 1996.
- 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.