Global Patent Index - EP 0664356 B1

EP 0664356 B1 20000705 - Process and apparatus for improving the quality of multi-layer papers

Title (en)

Process and apparatus for improving the quality of multi-layer papers

Title (de)

Verfahren und Vorrichtung zur Verbesserung der Papierqualität bei Mehrschicht-und Mehrlagenpapieren

Title (fr)

Procédé et dispositif pour améliorer la qualité des papiers à plusieurs couches

Publication

EP 0664356 B1 20000705 (DE)

Application

EP 95100234 A 19950110

Priority

DE 4401761 A 19940122

Abstract (en)

[origin: EP0664356A2] Improvement of multilayer paper quality in the wet working section of a paper machine entails at least two different quality pulps for paper strip mfr.; collection and recycling of dilute suspension drained from a screen in quite separate containers where at least most of a first pulp is drained through a first screen, corresp. for a second pulp and where the suspensions from each screen are separately gathered and reintroduced to the corresp. pulp i.e. paper layer. The appts. for the implementation comprises: appts. and pipework for gathering the separate dilute suspensions in accordance with quality levels and pipework for the re-introduction of the suspensions. Where a two-layer strip is formed by passing two pulp layers through a continuous double-sided screen, the gathering of the different dilute suspensions is carried out mainly in the screens' initial zone. In the formation of a triple layer sheet where the dilute suspension extracted from a first screen originates essentially from the outer layers it is reintroduced to them, while that from a later screen is reintroduced to the middle layer. The outer layers (S1, S3) can originate from approx. the same pulp and enclose a middle layer (S2).

IPC 1-7

D21F 11/04; D21F 9/00

IPC 8 full level

D21F 9/02 (2006.01); D21F 9/00 (2006.01); D21F 11/04 (2006.01); D21H 17/63 (2006.01)

CPC (source: EP US)

D21F 9/006 (2013.01 - EP US); D21F 11/04 (2013.01 - EP US)

Designated contracting state (EPC)

AT DE SE

DOCDB simple family (publication)

EP 0664356 A2 19950726; EP 0664356 A3 19960612; EP 0664356 B1 20000705; AT E194398 T1 20000715; CA 2140734 A1 19950723; CA 2140734 C 20060606; DE 4401761 A1 19950727; DE 4401761 C2 19970424; DE 59508521 D1 20000810; FI 111862 B 20030930; FI 950131 A0 19950111; FI 950131 A 19950723; JP H07300789 A 19951114; US 5639349 A 19970617

DOCDB simple family (application)

EP 95100234 A 19950110; AT 95100234 T 19950110; CA 2140734 A 19950120; DE 4401761 A 19940122; DE 59508521 T 19950110; FI 950131 A 19950111; JP 741895 A 19950120; US 37702695 A 19950120