Patent Yard Sign in
Expired Canadian patentCanada

Crystalline polybutene-1 compositions

CA 1280840 C · Owner: Wakatsuki, Kizuku · Inventors: Kakugo, Masahiro; Wakatsuki, Kizuku

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

A crystalline polybutene-l composition containing from from 1 x 10-6 to 10% by weight of a vinylcycloalkane unit having a melting point of 180°C or higher in terms of its homopolymer, is disclosed. The composition has a markedly improved rate of crystal conversion of polybutene-l.

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 26, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 26, 2008.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJune 12, 1985
GrantedFebruary 26, 1991
Term endedFebruary 26, 2008
Patent numberCA 1280840 C
Classification (IPC)C08L23/20

Timeline

Timeline From CIPO dates

19861989199219951998200120042007Application filedJune 12, 1985Patent grantedFeb 26, 1991Term endedFeb 26, 2008

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.