(19)
(11) EP 1 244 851 A1

(12)

(43) Date of publication:
02.10.2002 Bulletin 2002/40

(21) Application number: 00936926.5

(22) Date of filing: 14.06.2000
(51) International Patent Classification (IPC)7: D21H 21/14
// D21H17:14
(86) International application number:
PCT/FI0000/532
(87) International publication number:
WO 0007/7301 (21.12.2000 Gazette 2000/51)
(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

(30) Priority: 15.06.1999 FI 991366

(71) Applicant: KEMIRA CHEMICALS OY
00101 Helsinki (FI)

(72) Inventors:
  • JÄKÄRÄ, Jukka
    FIN-65100 Vaasa (FI)
  • PAREN, Aarto
    FIN-65200 Vaasa (FI)

(74) Representative: Svensson, Johan Henrik et al
Berggren Oy Ab,P.O. Box 16
00101 Helsinki
00101 Helsinki (FI)

   


(54) METHOD TO IMPROVE THE OPACITY OF MECHANICAL PULP BY USING ALIPHATIC PEROXYACIDS AND USE OF PEROXYACIDS TO IMPROVE OPACITY