Improved insert for thermoforming
CA 2265530 C · Owner: Aristech Acrylics Llc · Inventors: Cheesman, Harry W.; Minghetti, Ettore
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to mold inserts suitable for use with thermoformable sheets made of poly(methyl) methacrylate and other thermoplastic sheet material. The inserts become an integrated part of the thermoformed product, and are characterized by having at least one removable portion or plug. The plug(s) are removed during the thermoforming process and , allow the thermoformed sheet material to shrink without creating undesirable levels of stress in the sheet material. This prevents cracking or other failure of the sheet material.
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 June 26, 1998 and granted December 25, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 26, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 26, 2020.
- 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.