公开(公告)号：JPH11166031A

公开(公告)日：1999-06-22

申请号：JP22834598

申请日：1998-08-12

Applicant: EMTEC MAGNETICS GMBH

Inventor： WEINGART FRANZ ,  HACKL CHRISTA ,  KRECH RUEDIGER ,  BAUER STEPHAN ,  KOHL ALBERT ,  KRESS RIA ,  SCHELBLE JOSEF ,  BOHRMANN HANS-GUENTHER

IPC: C08G18/28 ,  C08G18/08 ,  C08G18/38 ,  C08G18/42 ,  C08G18/66 ,  C09D5/23 ,  C09D175/04 ,  G11B5/702

Abstract: PROBLEM TO BE SOLVED: To obtain a thermoplastic polyurethane containing no isocyanate group, useful as a binder having improved dispersion characteristics for a mag netic recording medium having excellent magnetic characteristics, by subjecting a specific constituent component to melt polymerization and specifying a molecu lar weight, etc. SOLUTION: Constituent components comprising (A) a 1 mol of a polyol having 400-4,000 molecular weigh, (B) 0.3-9 mol of a mixture of (i) optionally a 2-18C diol and (ii) 0.03-0.4 mol of a diol containing one or more acidic groups, (C) 0-1 mol of a 3-18C polyol containing three or more OH groups, (D) 1.25-13 mols of a 6-30C diisocyanate and (E) 0-1 mol of a 2-16C primary or secondary amino-alcohol are subjected to melt polymerization so as to make the molar ratio of OH group and NH group in the components A, B, C and E to NCO group in the component D of 0.98-1.4 to give the objective polyurethane containing an acidic group, soluble in tetrahydrofuran and having 15,000-70,000 molecular weight.

公开(公告)号：DE10050710A1

公开(公告)日：2002-04-25

申请号：DE10050710

申请日：2000-10-13

Applicant: EMTEC MAGNETICS GMBH

Inventor： HEES ULRIKE ,  BOHRMANN HANS-GUENTHER ,  RAETHER BENEDIKT ,  KRESS RIA ,  KOHL ALBERT

IPC: C08G18/08 ,  C08G18/40 ,  C08G18/50 ,  C08G18/76 ,  C09D5/23 ,  G11B5/702 ,  C08G18/48 ,  C08L75/04 ,  B32B15/08

Abstract: A polyurethane (I) has at least one anionic anchor group L which is covalently bonded to a nitrogen atom containing polyether segment in the polyurethane. Independent claims are included for (i) a binding agent (II) containing a thermoplastic polyurethane (I) (ii) a magnetic dispersion comprising a magnetic or magnetisable pigment and a polyurethane (I) or binding agent (II) (iii) a process for the production of the polyurethane (I) by addition of difuntional linear or branched polyetheramine having at least one covalently bonded anionic group L. (iv) a magnetic recording medium containing the polyurethane (I) or binding agent (II).

公开(公告)号：DE19734893A1

公开(公告)日：1999-02-18

申请号：DE19734893

申请日：1997-08-12

Applicant: EMTEC MAGNETICS GMBH

Inventor： WEINGART FRANZ ,  HACKL CHRISTA ,  KRECH RUEDIGER ,  BAUER STEPHAN ,  KOHL ALBERT ,  KRESS RIA ,  SCHELBLE JOSEF ,  BOHRMANN HANS-GUENTHER

IPC: C08G18/28 ,  C08G18/08 ,  C08G18/38 ,  C08G18/42 ,  C08G18/66 ,  C09D5/23 ,  C09D175/04 ,  G11B5/702 ,  C08G18/34 ,  C08G18/50 ,  C08G18/32 ,  C08G18/76 ,  G11B5/62 ,  C08L75/04

Abstract: Thermoplastic polyurethane (I) with a molecular weight of 15000-70000, which contains acid groups, is soluble in tetrahydrofuran (THF) and is free from isocyanate (NCO) groups, comprises: (A) 1 mole polyol with a molecular weight of 400-4000, (B) 0.3-9 mole mixture of (B1) optionally a 2-18 carbon (C) diol and (B2) 0.03-0.4 mole diol containing acid group(s), (C) 0-1 mole 3-18 C polyol with NOTLESS 3 hydroxyl (OH) groups, (D) 1.25-13 mole 6-30 C diisocyanate and (E) 0-1 mole primary or secondary 2-16 C amino-alcohol. The molar ratio of OH and optionally NH groups in the sum of components A, B, C and E to NCO groups in D is 0.98-1.4. (I) is obtained by reacting these components in the melt. Also claimed are: (i) the preparation of (I) in this way; and (ii) magnetic recording media with a magnetic layer containing (I).