Method and device for the production of polyethylene terephthalate preforms
CA 2526232 C · Owner: L'Air Liquide, Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'Etude Et L'Exploitation Des Procedes Georges Claude · Inventors: Benjamin, Yves; Rames-Langlade, Geraldine
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a method and device for the production of polyethylene terephthalate preforms. The inventive device comprises: a feed hopper (3) for polymer granules arriving from a dryer; means (1 2) for heating, moving and pressurising the polymer such as a heated screw conveyor; and polymer-shaping means. According to the invention an inert gas is injected at a point (4 5, etc.) which is located at the dryer at the hopper or downstream of the hopper said gas being pre-heated to a temperature of at least 170 ·C and preferably, within a temperature range of between 170 ·C and 250 ·C.
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 7, 2004 and granted August 28, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 7, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 7, 2026.
- 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.