Patent · US Expired

Method for optically brightening paper

US6464832B2 · kind B2 · utility

11Cited by

12References

13Claims

0Family size

Assignee

Ciba Specialty Chemicals Corporation · US

Inventors

Thomas Engelhardt · Rheinfelden (Baden), DE
Peter Rohringer · Allschwil, CH

Key dates

Filing date	Sep 10, 2001
Grant date	Oct 15, 2002
Priority date	—
Expiry date	Sep 10, 2021

Classification

Technology area (CPC D)Textiles; Paper
CPC primaryD21H17/68
WIPO fieldTextile and paper machines
WIPO sectorMechanical engineering

Abstract

A simplified method for the optical brightening of paper either in the pulp mass, the size or metering press or by coating by the use of a formulation of an optical brightening agent together with a swellable layered silicate.

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