公开(公告)号：JPH04286717A

公开(公告)日：1992-10-12

申请号：JP32565191

申请日：1991-12-10

Applicant: BASF MAGNETICS GMBH

Inventor： UBUE KEPERAA ,  MIHIYAERU BOBURITSUHI ,  HERUMUUTO AUBUETAA ,  RUDORUFU ZUYUTEINGAA ,  ARUBERUTO KOORU ,  HERUMAN DEIKOU ,  BUERUNAA RENTSU ,  GUREGOORU BUROTSUTO

IPC: C08G18/08 ,  C08G18/12 ,  C09D5/00 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/04 ,  G11B5/702

Abstract: PURPOSE: To obtain a binder system for finely divided ferromagnetic powders corresponding to a high-density recording system by using branched polyurethane which does not contain isocyanate and soluble in tetrahydrofuran. CONSTITUTION: The polyurethane used as the binder of a magnetic layer has a sulfonate group on its branched chain, has an OH-contg. urea group at its molecule terminal, and has a mol.wt. of 4,000 to 30,000. The polyurethane is prepared from 1mol polydiol having a mol.wt. of 400 to 4,000, 0.3 to 9mol mixture, 0.01 to 1mol 3 to 25C trial or polyol, 1.25 to 13mol 6 to 30C diisocyanate and 0.05 to 4mol OH-contg. primary or secondary amine reactive with isocyanate.

公开(公告)号：JPH04298818A

公开(公告)日：1992-10-22

申请号：JP32871091

申请日：1991-12-12

Applicant: BASF MAGNETICS GMBH

Inventor： UBUE KEPERAA ,  HERUMAN DEIKOU ,  HERUMUUTO AUBUETAA ,  MIHIYAERU BOBURITSUHI ,  YOTSUHEN RUDORUFU ,  GUREGOORU BUROTSUTO ,  ARUBERUTO KOORU ,  BUERUNAA RENTSU ,  RUDORUFU ZUYUTEINGAA

IPC: C08G18/65 ,  C08G18/08 ,  C08G18/12 ,  C09D5/00 ,  C09D5/23 ,  C09D175/04 ,  G11B5/02 ,  G11B5/702

Abstract: PURPOSE: To provide a novel thermoplastic elastic polyurethane resin which is easily soluble in ether and ketones and has excellent dispersion performance and imparts high mechanical stability and excellent electromagnetic conversion characteristics to a magnetic recording medium produced by using the same. CONSTITUTION: This magnetic recording medium is formed by using the binder contg. >=50wt.% the thermoplastic elastic polymethane resin consisting of the following components: A) 1mol polydiol having a mol.wt. of 400 to 4,000, B) 0.3 to 10mol mixture composed of the following: B1) >=1 kinds of 2 to 18C diols and B2) diol having one or more pieces of sulfonate groups, C) 0.01 to 1mol 3 to 25C triol or polyol, D) 1.3 to 13mol >=1 kinds of 6 to 30C dissocyanate and E) 0.09 to 2mol 2 to 26C aminoalcohol. The ratios of the OH groups of the components A) to C): the NCO groups of the component D): the amino groups of the component E) are 1:1.03 to 1.3:0.03 to 0.3.