Process for making suede-like sheet material

US4612688A · kind A · utility

Assignee

• Akzona Incorporated · US

Inventors

• Klaus Gerlach · Aschaffenburg, DE
• Nikolaus Mathes · Höchst im Odenwald, DE
• Hans-Jurgen Pitowski · Miltenberg, DE
• Friedbert Wechs · Bad Mergentheim, DE

Key dates

• Filing date: Mar 21, 1985
• Grant date: Sep 23, 1986
• Expiry date: Mar 21, 2005

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T442/633
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

Staple fibers made from crimped, in particular compression crimped, multicomponent filaments of the matrix/segment type, the cross section of which shows, in addition to the matrix, at least 6 peripheral wedge-shaped or lenticular segments, not completely covered by the matrix, are processed into a web, which is then mechanically bonded, preferably by needling. Subsequently, the fabric is subjected to a shrinkage process, by which its density is increased by more than 30%, themulticomponent fibers being completely or partly split up into their components. The difference in shrinkage between the components should be at least 10%. The liquids used for the shrinkage treatment are in particular organic liquids, such as methylene chloride, as well as other liquids producing a difference in shrinkage of at least 20%. The fabric is then impregnated with a solution of polyurethane on the basis of polyglycols, specifically polytetramethylene glycol, diisocyanates and low-molecular glycols as chain lengtheners, the jelling temperature of the solution being higher than the roomtemperature and higher than the temperature of the coagulation bath; the polyurethane is coagulated by cooling and/or…