Thermoplastic hardboard from acetylated mat
CA 1162702 A · Owner: United States Gypsum Company · Inventors: Leichti, Robert J.; House, Cynthia B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A wet-felted mat of wood fibers is acetylated by coating the mat with a quantity of acetic anhydride ranging from 5 to 70% by volume of the mat and heating the mat at a temperature of from 150 to 300° F. while confining substantially all of the acetic anhydride within the mat for about 20 to 120 minutes. The acetylated mat is pressed into hardboard which may be bent into a variety of loops, spirals helices, and, other curvilinear shapes to make articles of furniture pro-, tective packaging products and the like.
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 28, 1984. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 28, 2001.
- 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.