Global Patent Index - EP 1101860 A1

EP 1101860 A1 2001-05-23 - Method for bleaching pulp with activated ozone

Title (en)

Method for bleaching pulp with activated ozone

Title (de)

Verfahren zum Bleichen von Pulpe mittels aktivem Ozon

Title (fr)

Procédé de blanchiment de pate a papier par ozone activé

Publication

EP 1101860 A1 (EN)

Application

EP 00125129 A

Priority

US 44332399 A

Abstract (en)

An ozone based bleaching method for bleaching lignocellulosic materials comprising a bleaching sequence of at least four sequential stages, said stages including an oxidative treatment stage, an alkaline extraction stage, an activated ozone bleaching stage, and a final bleaching stage to produce a pulp of desired final brightness. The activated ozone bleaching stage comprises the addition of an ethanol/DMSO mixture to the pulp prior to the ozone reaction.

IPC 1-7 (main, further and additional classification)

D21C 9/10

IPC 8 full level (invention and additional information)

D21C 9/10 (2006.01); D21C 9/153 (2006.01)

CPC (invention and additional information)

D21C 9/1005 (2013.01); D21C 9/101 (2013.01); D21C 9/153 (2013.01)

Citation (search report)

  • [A] WO 9823811 A1 19980604 - KESKUSLABORATORIO [FI], et al
  • [A] US 5630906 A 19970520 - BOE JEAN-FRANÇOIS [FR], et al
  • [A] DE 3227843 A1 19830224 - CHEMIEFASER LENZING AG [AT]
  • [A] US 5411635 A 19950502 - FRANCIS RAYMOND C [US], et al
  • [AD] US 4959124 A 19900925 - TSAI TED Y [US]
  • [A] DATABASE PAPERCHEM2 [online] ALLISON, R. W.: "Effects of Temperature and Chemical Pretreatment on Pulp Bleaching with Ozone", XP002158244, retrieved from STN Database accession no. 7580 & (JUNE 18-21, 1985) PP. 47-53. [ENGL.]. MEETING INFO.: CPPA/TAPPI INT. PULP BLEACHING CONF. (QUEBEC CITY) PROC..(JUNE 18-21, 1985) PP. 47-53. [ENGL.]. MEETING INFO.: CPPA/TAPPI INT. PULP BLEACHING CONF. (QUEBEC CITY) PROC..
  • [A] DATABASE PAPERCHEM2 [online] NI, Y. (UNIVERSITY OF NEW BRUNSWICK) ET AL: "ECF Sequence for the AlcellRG Process Including an Ethanol -Assisted Ozone Stage", XP002158245, retrieved from STN Database accession no. 5423 & TAPPI J., VOL. 81, NO. 4, P. 92. 4 REF., 3 TAB..TAPPI J., VOL. 81, NO. 4, P. 92. 4 REF., 3 TAB..

Designated contracting state (EPC)

DE ES FR GB IT

EPO simple patent family

EP 1101860 A1 20010523; BR 0005444 A 20010703; CA 2326311 A1 20010519; CN 1297085 A 20010530; KR 20010051774 A 20010625

INPADOC legal status


2002-09-11 [18W] WITHDRAWN

- Date of withdrawal: 20020723

2002-02-20 [AKX] PAYMENT OF DESIGNATION FEES

- Free text: DE ES FR GB IT

2001-07-25 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20010528

2001-05-23 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): DE ES FR GB IT

2001-05-23 [AX] REQUEST FOR EXTENSION OF THE EUROPEAN PATENT TO

- Free text: AL;LT;LV;MK;RO;SI