EP 0807704 B1 20001102 - Recovery of fibres from bonded nonwovens
Title (en)
Recovery of fibres from bonded nonwovens
Title (de)
Wiedergewinnung von Fasern aus gebundenen Faservliesen
Title (fr)
Récupération de fibres provenant de non-tissés liés
Publication
Application
Priority
DE 19619639 A 19960515
Abstract (en)
[origin: EP0807704A1] A method for removing a polymer binder containing carboxylate groups cross-linked via alkaline earth metal ions from impregnated nonwovens comprises: (1) the nonwoven is treated with an aqueous alkali salt solution so that the alkali salt anions combine with the alkaline earth metal cations to form a poorly soluble salt or chelate; and (2) the binder-free fibres are separated. Preferably a phase transfer catalyst, preferably an alkyl phenol ethoxylate, fatty alcohol ethoxylate, oxo alcohol ethoxylate or quat. organic ammonium salt, is used in the alkali salt solution. Calcium ions are the cations present. The binder comprises a radical-polymerised polymer containing 0.1-30 wt.% carboxylate groups, of which 50-100 wt.% are present as salts containing alkaline earth metal cations. The alkali salt solution has a temperature of 10-100 degrees C. The nonwoven is added to the alkali salt solution, which is then optionally stirred before separating the fibres 1-60 minutes later.
IPC 1-7
IPC 8 full level
D04H 1/435 (2012.01); D04H 1/587 (2012.01); D04H 1/64 (2006.01); D04H 1/645 (2012.01); D04H 3/011 (2012.01); D04H 3/12 (2006.01)
CPC (source: EP US)
D04H 1/435 (2013.01 - EP US); D04H 1/587 (2013.01 - EP US); D04H 1/645 (2013.01 - EP US); D04H 3/011 (2013.01 - EP US); D04H 3/12 (2013.01 - EP US); Y10S 260/31 (2013.01 - EP US); Y10S 260/43 (2013.01 - EP US)
Designated contracting state (EPC)
AT BE CH DE ES FR GB IT LI NL SE
DOCDB simple family (publication)
EP 0807704 A1 19971119; EP 0807704 B1 20001102; AT E197323 T1 20001115; DE 19619639 A1 19971120; DE 59702552 D1 20001207; ES 2152593 T3 20010201; US 6004428 A 19991221
DOCDB simple family (application)
EP 97107491 A 19970507; AT 97107491 T 19970507; DE 19619639 A 19960515; DE 59702552 T 19970507; ES 97107491 T 19970507; US 85206497 A 19970506