| (19) |
 |
|
(11) |
EP 1 306 484 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
29.09.2004 Bulletin 2004/40 |
| (43) |
Date of publication A2: |
|
02.05.2003 Bulletin 2003/18 |
| (22) |
Date of filing: 17.10.2002 |
|
| (51) |
International Patent Classification (IPC)7: D21H 17/07 |
|
| (84) |
Designated Contracting States: |
|
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR |
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Designated Extension States: |
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AL LT LV MK RO SI |
| (30) |
Priority: |
25.10.2001 GB 0125605
|
| (71) |
Applicant: Arjo Wiggins Fine Papers Limited |
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Basingstoke, Hampshire RG24 8BA (GB) |
|
| (72) |
Inventor: |
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- Bracewell, Graham Robert
Canterbury, Kent CT1 1JD (GB)
|
| (74) |
Representative: Carré, Claudine Bernadette |
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Arjo Wiggins Legal & Intellectual Property Department 117, quai du Président Roosevelt
92442 Issy-les-Moulineaux Cedex
92442 Issy-les-Moulineaux Cedex (FR) |
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| |
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(57) A process for modifying natural tracing paper to reduce its susceptibility to cracking
on folding comprises the step of treating the paper with an aqueous urea solution
of a concentration of at least 40% by weight, preferably about 50% by weight. The
treatment is preferably carried out at the size press or bath of the paper machine
on which the tracing paper is produced. The urea solution may also contain a surface
sizing agent. The resulting treated tracing paper is particularly suitable for the
production of envelopes, or packaging for luxury products.