Patent · US Expired

Papermaking process using a specified NSF to silica-based particle ratio

US7156955B2 · kind B2 · utility

6Cited by
20References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 20, 2002
Grant dateJan 2, 2007
Priority date
Expiry dateSep 22, 2023

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD21H21/10
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

The present invention refers to a process for the production of paper from a suspension containing cellulosic fibers, and optionally fillers, comprising adding to the suspension at least one cationic organic polymer and an aqueous silica-containing composition comprising an anionic naphthalene sulphonate formaldehyde condensate and anionic silica-based particles, the composition having a weight ratio of naphthalene sulphonate formaldehyde condensate to silica-based particles within the range of from 0.2:1 to 99:1, and containing naphthalene sulphonate formaldehyde condensate and silica-based particles in an amount of at least 0.01% by weight, based on the total weight of the aqueous silica-containing composition, and with the proviso that the composition contains substantially no cellulose-reactive sizing agent. The invention also encompasses an aqueous silica-containing composition and a method for preparation of an aqueous silica-containing compound.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.