Global Patent Index - EP 1316639 A1

EP 1316639 A1 2003-06-04 - Use of ozone for increasing the wet strength of paper and nonwoven

Title (en)

Use of ozone for increasing the wet strength of paper and nonwoven

Title (de)

Die Verwendung von Ozone zur Erhöhung der Nassfestigkeit von Papier und Vliesstoff

Title (fr)

L'utilisation de l'ozone pour augmenter de la resistance humide de papier et de non tissé

Publication

EP 1316639 A1 (EN)

Application

EP 02026454 A

Priority

GB 0128735 A

Abstract (en)

The present invention relates to the use of a treatment sequence comprising ozonation under acidic conditions followed by an acidic wash for enhancing the wet strength of a cellulosic fibrous material, as well as the corresponding process. Preferably the ozone treatment and the acidic wash are followed by a second ozonation step under acidic conditions. The present invention further concerns a fibrous cellulosic material obtainable by this treatment sequence which preferably has a breaking length of at least 100 m. The present invention thus allows increasing the wet strength of a cellulosic fibrous material (e.g. pulp), paper or nonwoven without the use of additives, such as wet strength agents. This use of ozone is very simple and efficient, and leads to highly pure products. The use of ozone as the only treatment chemical in particular avoids the introduction of so-called "non-process elements" (NPE) into the treatment system, for instance metal oxides such as MgO, which are frequently used in the oxidative treatment of pulps.

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

D21C 9/153; D21H 21/20

IPC 8 full level (invention and additional information)

D21C 9/00 (2006.01); D21C 9/153 (2006.01)

CPC (invention and additional information)

D21C 9/002 (2013.01); D21C 9/153 (2013.01)

Citation (search report)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

EPO simple patent family

EP 1316639 A1 20030604; GB 0128735 D0 20020123; GB 2382592 A 20030604

INPADOC legal status


2006-02-08 [18D] APPLICATION DEEMED TO BE WITHDRAWN

- Effective date: 20050804

2005-03-09 [17Q] FIRST EXAMINATION REPORT

- Effective date: 20050124

2004-02-25 [AKX] PAYMENT OF DESIGNATION FEES

- Designated State(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

2003-10-29 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20030829

2003-06-04 [AK] DESIGNATED CONTRACTING STATES:

- Designated State(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

2003-06-04 [AX] REQUEST FOR EXTENSION OF THE EUROPEAN PATENT TO:

- Countries: AL LT LV MK RO SI