EP 0578304 B1 19960918 - Process for bleaching a chemical paper pulp
Title (en)
Process for bleaching a chemical paper pulp
Title (de)
Verfahren zum Bleichen eines chemischen Zellstoffs
Title (fr)
Procédé pour le blanchiment d'une pâte à papier chimique
Publication
Application
Priority
BE 9200626 A 19920706
Abstract (en)
[origin: EP0578304A1] Process for bleaching a chemical paper pulp to a brightness of at least 89 DEG ISO, consisting in subjecting the pulp to a multistage treatment sequence comprising a final stage of bleaching with hydrogen peroxide in alkaline medium performed in the presence of at least one stabilising agent and at a pulp consistency of at least 25 % by weight of solids content, the stages preceding this final stage having purified the pulp so that its manganese content does not exceed 3 ppm by weight relative to the solids content and that the pulp has been delignified beforehand to a kappa value not exceeding 5.
IPC 1-7
IPC 8 full level
CPC (source: EP US)
D21C 9/1057 (2013.01 - EP US); D21C 9/163 (2013.01 - EP US)
Citation (examination)
- WO 9314262 A1 19930722 - SUNDS DEFIBRATOR IND AB [SE]
- EP 0402335 A2 19901212 - EKA NOBEL AB [SE]
- EP 0377981 A2 19900718 - DU PONT [US]
- Journal of wood chemistry and technology, vol. 2(3), 1982, pages 231-250; G. Gellerstedt et al "Chemical aspects of hydrogen peroxide bleaching. Part II: The bleaching of kraft pulps".
Designated contracting state (EPC)
AT BE CH DE ES FR LI NL PT SE
DOCDB simple family (publication)
EP 0578304 A1 19940112; EP 0578304 B1 19960918; AR 247258 A1 19941130; AT E143074 T1 19961015; AU 4170593 A 19940113; AU 654623 B2 19941110; BE 1006056 A3 19940503; BR 9302764 A 19940208; CA 2099827 A1 19940107; DE 69304822 D1 19961024; DE 69304822 T2 19970410; ES 2094465 T3 19970116; FI 111170 B 20030613; FI 933103 A0 19930706; FI 933103 A 19940107; JP H06166981 A 19940614; NZ 248029 A 19951026; SI 9300362 A 19940331; SK 70293 A3 19940406; US 6221209 B1 20010424
DOCDB simple family (application)
EP 93201886 A 19930629; AR 32534193 A 19930705; AT 93201886 T 19930629; AU 4170593 A 19930702; BE 9200626 A 19920706; BR 9302764 A 19930705; CA 2099827 A 19930705; DE 69304822 T 19930629; ES 93201886 T 19930629; FI 933103 A 19930706; JP 16713293 A 19930706; NZ 24802993 A 19930630; SI 9300362 A 19930706; SK 70293 A 19930702; US 8318393 A 19930629