Process for the preparation of perylene pigments
CA 2364991 C · Owner: Greene, Michael J. · Inventors: Thompson, Brian L.; Greene, Michael J.; Sandefur, Charles W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a process for preparing perylene pigment compositions by (a) reacting at a temperature of less than about 25°C a mixture of (1) a perylene tetracarboxylic compound (2) at least about 0.1% by weight, relative to the perylene tetracarboxylic compound of a surfactant of formula (I) (see formula I) wherein R1 R2, R3, X, Y, Z, and Z' are defined herein (3) an equivalent excess, relative to the amount of the perylene tetracarboxylic compound of ammonia or a primary amine R A-NH2, wherein R A is defined herein and (4) optionally, a solvent, to form a perylene intermediate; (b) heating the perylene intermediate at a temperature of about 50°C to about 250°C optionally in …
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 December 14, 2001 and granted March 15, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 14, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 14, 2023.
- 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.