Preparation of thermoformed plastic articles
CA 1283237 C · Owner: Coster, Harmen Zwier Klasinus · Inventors: Coster, Harmen Zwier Klasinus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
PREPARATION OF MOULDED ARTICLES" Moulded articles of uniform wall thickness are prepared by vacuum-forming or thermoforming a composition comprising a uniform blend of, as base resin, a moulding grade resin having a continuous phase of a first copolymer of a styrenic monomer and an ethylenically unsaturated nitrile and a minor proportion of, as additive resin, a second copolymer of a styrenic monomer and an ethylenically unsaturated nitrile having an ultra high molecular weight, the forming operation being carried out at least 50°C above the glass transition temperature of the base resin and at a stress level of at most 1 MPa.
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 April 16, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 16, 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.
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.