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：JPH06301958A

公开(公告)日：1994-10-28

申请号：JP31042593

申请日：1993-12-10

Applicant: BASF MAGNETICS GMBH

Inventor： GUREEGORU BUROTO ,  HERUMAN DEIKOBU ,  MIHIYAERU BOBURITSUHI ,  HERUMUUTO AUBUETAA ,  ARUBERUTO KOORU ,  RUDORUFU ZUYUTEINGAA ,  YOTSUHEN RUDORUFU

IPC: C08G18/38 ,  C09D5/23 ,  G11B5/702

Abstract: PURPOSE: To improve recording performance and mechanical stability by incorpo rating a thermoplastic and elastic polyurethane binder which is easily dissolved in either and/or ketone and has good dispersability into a magnetic medium. CONSTITUTION: This magnetic recording medium comprises a nonmagnetic substrate and a magnetic layer formed of a magnetic material which is finely dispersed in a binder containing 50wt.% thermoplastic polyurethane. The thermoplastic polyurethane is a branched-chain polyurethane which is soluble with tetrahydrofuran and contains no isocyanate group. The polyurethane has urea groups with or without OH groups on the end of the chain and 30000 to 100000mol.wt.(Mw) and comprises the following five components. (A) One mol of polydiol having 400 to 10000mol.wt., (B) 0.3 to 10 moles of mixture of 12-18C diol and diol having phosphone groups, (C) 0.01 to 1 mole of 3-25C triol or polyol. (D) 1.3 to 13 moles of 6-30C diisocyanate, and (E) 0.09 to 2 moles of 2-16C aminoalcohol or monoamine containing no OH group. The ratios of OH groups in the components (A) to (C), NCO groups in the components (D) and the amino groups in the component (E) are 1:(1.03 to 1.3):(0.03 to 0.3).

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.