Pulp treatment methods
US4976819A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 28, 1988 |
| Grant date | Dec 11, 1990 |
| Priority date | — |
| Expiry date | Apr 28, 2008 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H15/04
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Mechanical treatment of a pulp slurry of up to 50% O.D. consistency by dewatering and compacting the pulp permanently twists and kinks individual fibers to a degree that is substantially irreversible when they are subsequently subjected to papermaking process steps. The preferred device for imparting such permanent twisting and kinking is a plug screw feeder. Pulp that has been so treated exhibits increased desired drainability in the wet section of a papermachine. Such treated pulp also loses water vapor more easily in the dryer section than untreated pulp, and correspondingly results in less energy consumption in the dryer section of a papermachine. Pulp treated in accordance with the invention also exhibits increased absorbency. Tissue or other soft paper products produced from softwood pulp treated in accordance with the invention exhibit significantly increased softness over such untreated softwood pulp. Pulp treated in accordance with the invention is also useful in enhancing properties, for example bulk, in other paper products.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.