Process for controlling the intrinsic viscosity of sulfite pulp
CA 1080910 A · Owner: Itt Industries · Inventors: Conca, Romeo J.; Sloan, Tod H.; Gray, John P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure, A process for accurately controlling the intrinsic viscosity of sulfite pulp at the termination of a digestion operation comprising predetermining the duration of digestion time required to obtain a given pulp intrinsic viscosity for a range of initial weight ratios of combined SO2 to wood determining during the digestion operation the initial weight ratio of combined SO2 to wood by measuring the rate of change of absorbance in the digestion cooking liquor and terminating the digestion operation at a time corresponding to the predetermined time required to obtain the given pulp intrinsic viscosity at the aforesaid combined SO2 to wood ratio. - 1 -
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 July 8, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 8, 1997.
- 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.