Swollen starch-latex compositions for use in papermaking
US7074845B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 7, 2003 |
| Grant date | Jul 11, 2006 |
| Priority date | — |
| Expiry date | Oct 22, 2023 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H21/52
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A novel filler treatment comprising the preparation of swollen starch-latex compositions, prepared in the presence or absence of co-additives, and the addition of the said composition to a filler suspension, has been developed. Use of the treated filler during papermaking improves filler retention and produces filled papers where addition of the filler has only a minimal negative effect on strength properties. The swollen starch-latex compositions can be prepared in a batch or jet cooker, or by mixing with hot water under controlled conditions (i.e., temperature, pH, mixing, mixing time) in order to make the starch granules swell sufficiently to improve their properties as a filler additive but avoiding excess swelling leading to their rupture. The swollen starch-latex composition is then rapidly mixed with the filler slurry, preferably in a static mixer, and added to the papermaking furnish at a point prior to the headbox of the paper machine. The starch-latex composition can be used with wood-free or wood-containing furnishes. The treated filler is easily retained in the web during papermaking, improves drainage, and gives sheets having good formation. Sheets made with the treate…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.