公开(公告)号：DE19644347C2

公开(公告)日：1999-08-12

申请号：DE19644347

申请日：1996-10-25

Applicant: EMTEC MAGNETICS GMBH

Inventor： WUENSCH THOMAS DR ,  KRESS RIA DR ,  LOCH WERNER DR ,  LEHNER AUGUST ,  KOHL ALBERT ,  SCHNEIDER NORBERT ,  BURKHARDT UWE

IPC: C08K3/08 ,  C08G18/10 ,  C08G18/32 ,  C08G18/38 ,  C08G18/64 ,  C08G18/72 ,  C08K3/22 ,  C08L75/00 ,  C08L75/04 ,  C09D5/23 ,  C09D175/00 ,  C09D175/04 ,  G11B5/702 ,  C08G18/30 ,  C09D17/00

Abstract: Hydroxyl-containing polyurethanes I are composed essentially of a) a diisocyanate of 6 to 30 carbon atoms (component II), b) a component III comprising alpha ) an aliphatic diol of 2 to 20 carbon atoms or beta ) an aromatic-aliphatic or aromatic-cycloaliphatic diol of 8 to 30 carbon atoms having nonphenolic hydroxyl groups as hydroxyl groups of the diol and c) a polyhydric alcohol having at least 3 hydroxyl groups, 3 to 18 carbon atoms and nonphenolic hydroxyl groups as hydroxyl groups of the alcohol (component IV), the amounts of components II to IV being such that the total number of nonphenolic hydroxyl groups is from 1.1 to 5.0 per isocyanate group of II. The polyurethanes can be used as binders or binder components for pigment-containing coatings, in particular for the production of magnetic recording materials.

公开(公告)号：DE19757670A1

公开(公告)日：1999-07-01

申请号：DE19757670

申请日：1997-12-23

Applicant: EMTEC MAGNETICS GMBH

Inventor： LEHNER AUGUST ,  KOHL ALBERT ,  KRESS RIA DR ,  WUENSCH THOMAS DR ,  WEINGART FRANZ DR

IPC: C09D5/23 ,  C09D175/04 ,  G11B5/702 ,  C08G18/10 ,  C08G18/32 ,  C08G18/65 ,  C08G18/38

Abstract: The present invention relates to a magnetic recording medium, comprising a non-magnetic support and at least one magnetic coating applied thereto, whereby said coating contains at least one finely distributed magnetic material dispersed in a binding agent. Said binding agent contains at least one polyurethane resin (PV, which can be obtained by cross-linking at least one polyisocyanate (A) with at least one polyurethane prepolymer (B) which is free of isocyanate groups and contains at least 3 active hydrogen atoms. The invention is characterised in that the polyurethane prepolymer (B) has at least two hydroxyl groups and at least one primary and/or secondary amino group. The invention also relates to a method for producing a magnetic recording medium, polyurethane prepolymers B) which are free of isocyanate and a method for the production and use thereof.