EP 1152086 A3 20020807 - Process and apparatus for making a multiply and /or multilayer fibrous web
Title (en)
Process and apparatus for making a multiply and /or multilayer fibrous web
Title (de)
Verfahren sowie Vorrichtung zur Bildung einer mehrschichtigen und/oder mehrlagigen Faserstoffbahn
Title (fr)
Procédé et dispositif de fabrication d'une feuille fibreuse multicouche et/ou multijet
Publication
Application
Priority
DE 10021979 A 20000505
Abstract (en)
[origin: EP1152086A2] To form a multi-layer fiber web (34), especially of paper or cardboard, at least one of the two outer layers (34',34) is from a fiber material with at least one additive at the fiber surfaces. For a multi-layer paper/cardboard web, the additive is deposited on the surfaces of hollow fibers and, in addition, within the hollow fibers and at their walls. The additive includes a filling material, and the outer layers of the web have a higher filling material content than a center layer. Calcium carbonate is used as the additive or filling material at the wet fibers, or is used as a precipitate. To apply the calcium carbonate to wet fibers, a medium with calcium oxide and/or calcium hydroxide is used so that at least a portion associates with the water at the fibers. The treated fibers are exposed to carbon dioxide to give a chemical reaction with the calcium carbonate at the fiber surfaces. The calcium oxide and/or calcium hydroxide is used at a rate of 0.1-50.0 wt.% of the fiber dry weight. The fibers are treated with carbon dioxide in a closed vessel, as a gas under pressure, during a mixing phase where a high shear effect is applied to the fibers using an energy of at least 10-50 W/hr/kg based on the dry weight. The fiber material is derived in a pulper from cellulose or used paper materials, or it is a never-dried pulp. An Independent claim is included for a papermaking/cardboard production machine, to produce a multi-layer web, with stock inlet channels (36,40) charged with fiber materials where an additive is deposited on the fiber surfaces at least partially. Preferred Features: The multi-layer stock inlet assembly (28) is structured to form a web with two outer layers or a sandwich with an intermediate layer, where the pulp for the outer layers has fibers with an additive on their surfaces.
IPC 1-7
IPC 8 full level
D06P 1/44 (2006.01); D21F 11/04 (2006.01); D21H 17/00 (2006.01); D21H 27/38 (2006.01)
CPC (source: EP US)
D21F 11/04 (2013.01 - EP US); D21H 27/38 (2013.01 - EP US)
Citation (search report)
- [X] WO 9801622 A1 19980115 - STORA PUBLICATION PAPER AG [DE], et al
- [X] DE 3720618 A1 19880107 - VALMET OY [FI]
- [A] DE 4436317 A1 19960418 - NALCO CHEMICAL CO [US]
- [DA] US 5223090 A 19930629 - KLUNGNESS JOHN H [US], et al
- [A] WO 9949133 A1 19990930 - PULP PAPER RES INST [CA]
- [A] DE 4311505 A1 19931014 - AUSSEDAT REY [FR]
- [A] DE 4237309 A1 19930408 - VOITH GMBH J M [DE]
- [A] DE 1940321 A1 19700730 - NEUMANN SALOMON
- [X] G. STENBERG: "MEHRSCHICHTIGE DRUCKPAPIERE-ERFAHRUNGEN MIT EINER NEUEN MEHRSCHICHTSANLAGE", WOCHENBLATT FÜR PAPIERFABRIKATION, no. 15, 1987, pages 662,664 - 667, XP002201349
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR
DOCDB simple family (publication)
EP 1152086 A2 20011107; EP 1152086 A3 20020807; EP 1152086 B1 20040602; AT E268411 T1 20040615; CA 2345600 A1 20011105; DE 10021979 A1 20011108; DE 50102455 D1 20040708; US 2001045265 A1 20011129; US 6627042 B2 20030930
DOCDB simple family (application)
EP 01106092 A 20010313; AT 01106092 T 20010313; CA 2345600 A 20010503; DE 10021979 A 20000505; DE 50102455 T 20010313; US 84807601 A 20010503