Method for preparing phenolic foams using anhydrous aryl sulfonic acid catalysts
CA 1209747 A · Owner: Koppers Company, Inc. · Inventors: Wojtyna, Vincent J.; Colton, James P.; Carlson, John D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is directed to a method of preparing a phenolic foam that has cell walls which are substantially free of perforations. The method comprises using certain anhydrous aryl sulfonic acids as the foaming and curing catalysts. The useful anhydrous aryl sulfonic acids are those which have a pKa of less than about 2.0 and which change the compatibility of the phenolic resole with water. The preferred anhydrous aryl sulfonic acid is a combination of toluene sulfonic acid and xylene sulfonic acid. The invention is also directed to a phenolic foam having cell walls which are substantially free of perforations and to foamable phenolic resole compositions for preparing the phenolic …
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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 August 12, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 12, 2003.
- 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
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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.