Process for preparing pulp for paper making
US4798651A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 31, 1987 |
| Grant date | Jan 17, 1989 |
| Priority date | — |
| Expiry date | Jul 31, 2007 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C1/00
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
This invention relates to an improved process for preparing pulp suitable for paper making. Although processes using explosive decompression have been known in the past, it has been believed that these must be conducted at relatively low temperatures. Although such known processes of explosive decompression resulted in a saving of power, the physical strength was low, the color was relatively dark and there was a considerable yield loss. This invention is to provide a process to achieve the saving of power resulting from the use of explosive decompression but in which there is good brightness, high yield and good fiber strength. The process of this invention defines conditions for achieving these objectives. These conditions include impregnation of the chips of other wood fragments under specified conditions and cooking with saturated steam at a high temperature and pressure followed by explosive decompression and refining.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.