Mixtures of fluorescent whitening agents
CA 1340088 C · Owner: Guglielmetti, Leonardo · Inventors: Meyer, Hans Rudolf; Reinehr, Dieter; Weber, Kurt
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Mixtures of fluorescent whitening agents consisting of 51 to 99 % by weight of a symmetrically or unsymmetrically substituted first 1,4-bis(cyanostyryl)benzene and 49 to 1 % by weight of an unsymmetrically substituted second 1,4-bis(cyanostyryl)benzene that differs from the first, a process for the preparation of said mixtures by condensing terephthalaldehyde with a di(C1-C4) alkyl-phosphonomethylbenzonitrile to cyano-4-formylstilbene which is, further condensed, either direct or aftqr isolation with at least, one other di(Cl-C4)alkylphosphonomethylbenzonitrile the use of, these mixtures for whitening polyester fibres and compositions, containing said mixtures for whitening polyester fibres.
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 October 20, 1998. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 20, 2015.
- 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.