Dyeable hot-bulked polypropylene fibers modified with a copolyamide
CA 2047791 C · Owner: Tietz, Raymond F. · Inventors: Tietz, Raymond F.; Tung, Wae-Hai
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Dyeable fibers are formed from polypropylene by blending a major portion of polypropylene with a minor portion of 1) a copolymer of nylon 6,6 and substantially equimolar amounts of hexamethylene diamine and an alkali metal salt of 5-sulfoisophthalic acid or 2) a basic reaction product of substantially equimolar amounts of N-(2-aminoethyl) piperazine and adipic acid hexamethylene, diamine and adipic acid and optionally .epsilon.-caprolactam. The blend is formed in an extruder and extruded into filaments which are quenched in air, stretched 2-4 x (preferably at an elevated temperature) and bulked using a jet of heated turbulent fluid. The thusly bulked filaments are then dyed.
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 July 24, 1991 and granted September 11, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 24, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 24, 2013.
- 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.