EP 0421172 A1 19910410 - Method of clouring or tinting paper.
Title (en)
Method of clouring or tinting paper.
Title (de)
Verfahren zum Färben von Papier.
Title (fr)
Procédé de teinture du papier.
Publication
Application
Priority
CA 615364 A 19890929
Abstract (en)
The colouring or tinting of paper is achieved during the paper making process by adding at least one of only the three primary colour dyes to a base furnish. The colouring or tinting provides a tighter control for any shade of white paper while maintaining maximum brightness and opacity. The control is obtained at a reduced cost compared to the use of fillers. The method comprises the steps of selecting a set of optical properties for a required paper representing luminosity value (L), red to green colour difference value (a), and yellow to blue colour difference value (b), measuring the L, a and b values of a base furnish, determining the deviations between the selected values and the measured values and adding at least one of only the three primary colour dyes, yellow, red and blue, to the base furnish to achieve the selected set of optical properties for the required paper.
IPC 1-7
IPC 8 full level
D21H 21/28 (2006.01); D21H 23/08 (2006.01)
CPC (source: EP)
D21H 21/28 (2013.01); D21H 23/08 (2013.01)
Citation (search report)
- [X] PAPER TECHNOL.IND. 27 No.5 Aug./Sept. 1986 pages 208-209, 211 B.E.EVANS ET AL : "Closed-loop color control and papermaking dyes."
- [X] DATABASE WPIL, no. 90-050579 Derwent Publications Ltd, London, GB, & SU-A-1477803 (Cell Paper Ind Prod )
- [A] TAPPI JOURNAL. vol. 55, no. 1, January 1972, ATLANTA US pages 140 - 144; J.A.VAN DEN AKKER: ""Spectral reflectance, transmittance, and color of paper and pulp ( usingspectrophotometer with reversed optics )."
Designated contracting state (EPC)
DE FR GB IT SE
DOCDB simple family (publication)
EP 0421172 A1 19910410; CA 1332663 C 19941025; FI 904764 A0 19900927
DOCDB simple family (application)
EP 90117789 A 19900915; CA 615364 A 19890929; FI 904764 A 19900927