Abstract: In the manufacture of viscose, and an elongate cellulose member such as standard viscose rayon fibre, with reduced alkali ratio from dissolving-grade cellulose such as wood pulp by irradiation with a high energy beam at a dose of 1-30 kGy, steeping in aqueous sodium hydroxide, pressing to form alkali cellulose, xanthating to form cellulose xanthate, dissolving in aqueous liquor to form viscose and (when elongate cellulose members are required) extruding through a die into an acid bath for coagulation and regeneration to form an elongate cellulose member which is then washed and dried, viscose filtration can be improved by including in the dissolving liquor for the cellulose xanthate an amount of from 200 to 10000 ppm by weight of a salt which consists of alkali metal or ammonium cations and anions of a strong acid.
Type:
Grant
Filed:
March 21, 2000
Date of Patent:
March 25, 2003
Assignee:
Acordis Kelheim GmbH
Inventors:
Klaus Fischer, Heinzhorst Möbius, Tatjana Poggi
Abstract: Cellulosic fibrids can be made by mixing together under turbulent conditions viscose and a coagulating and regenerating liquor containing preformed fibrids to form a suspension of fibrids in a spent liquor, and collecting the fibrids from the spent liquor.
Type:
Grant
Filed:
September 11, 2000
Date of Patent:
February 4, 2003
Assignee:
Acordis Kelheim GmbH
Inventors:
Andrzej Marek Mackiewicz, Guy Edward Scudder, Sabine Seddon
Abstract: Cellulosic fibrids can be made by mixing together under turbulent conditions viscose and a coagulating and regenerating liquor so as to form a suspension of soft macroscopic cellulosic particles in a spent liquor, collecting the particles, and comminuting them to form the fibrids.
Type:
Grant
Filed:
August 4, 2000
Date of Patent:
January 7, 2003
Assignee:
Acordis Kelheim GmbH
Inventors:
Richard Kinseher, Andrzej Marek Mackiewicz
Abstract: Cationic cellulose particles useful in papermaking comprise from greater than 10 up to 50 percent by weight on cellulose of a polymeric amine of weight-average molecular weight in the range from 100,000 to 1,000,000 comprising monomeric units having the formula:
—XCR3((CH2)nNR1R2)(CH2)m—
where X is selected from the group consisting of a chemical bond, O and NR4; R1 and R2 are the same or different and are selected from the group consisting of H, C1-C4 alkyl, phenyl and phenyl substituted with one, two or three substituents selected from the group consisting of C1-C4 alkyl, C1-C4 alkoxy, F, Cl and Br; R3 and R4 are independently selected from the group consisting of H, methyl and ethyl; m is an integer in the range from 1 to 4; and n is an integer in the range from 0 to 4.
Abstract: A process for producing viscose wherein the caustic soda used previously in the alkalization of electron-untreated cellulose can be used in the alkalization of electron-treated cellulosic material, provided the level of dispersed solids in the caustic soda does not exceed 0.16 g/l.
Abstract: Viscose filaments, preferably in staple fibre form, which have a decitex of less than 5.0 and a multi-limbed cross-section, the limbs having a length-to-width aspect ratio of at least 2:1. Examples of multi-limbed cross-sectional shapes are Y-, X-, H- and T-shapes. The fibre can be formed into woven, non-woven or knitted fabrics, and is especially useful for absorbent products.
Type:
Grant
Filed:
May 9, 1995
Date of Patent:
December 25, 2001
Assignee:
Acordis Kelheim GmbH
Inventors:
Andrew George Wilkes, Alan John Bartholomew