Buffered acid interleaving for glass sheets
CA 2185159 C · Owner: Ppg Industries Ohio, Inc. · Inventors: Franz, Helmut
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An organic acid anti-staining composition for glass sheets is disclosed herein whereby the corrosive effects of very low pH are eliminated by buffering the organic acid. The buffered organic acid has a less acidic pH but is as effective as unbuffered organic acid in neutralizing alkali formed by sodium from the glass to prevent staining of the glass surface.
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 September 9, 1996 and granted August 8, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 9, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 9, 2018.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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.