公开(公告)号：DE2364877A1

公开(公告)日：1975-07-03

申请号：DE2364877

申请日：1973-12-28

Applicant: BASF AG

Inventor： GROSS EGON VON DIPL CHEM DR ,  STRITZINGER HEINZ DIPL ING ,  HARTMANN JOB-WERNER DIPL CHEM ,  STEUERWALD MANFRED ,  KLEIN URSULA ,  SCHAEFER DIETER DIPL CHEM DR

IPC: C09D5/23 ,  G11B5/702 ,  G11B5/68

Abstract: Magnetic recording media comprising a non-magnetizable flexible base and a firmly adhering magnetic coating based on a dispersion, containing a silane, of a magnetic pigment in a polymeric binder, and a process for their manufacture. The silane is an aminoalkylsilane RnSi(OR')4-n, wherein n is 1, 2 or 3, R' is alkyl of 1 to 8 carbon atoms and R is aminoalkyl of the formula with one or more primary and/or secondary amino groups and from 3 to 11 carbon atoms. Magnetic recording media comprising a magnetic coating containing such a silane exhibit better abrasion resistance and better electromagnetic properties than comparable coatings.

公开(公告)号：DE2312848A1

公开(公告)日：1974-09-26

申请号：DE2312848

申请日：1973-03-15

Applicant: BASF AG

Inventor： STRITZINGER HEINZ DIPL ING ,  HARTMANN JOB-WERNER DIPL CHEM ,  BALZ WERNER DIPL CHEM DR ,  OSTERTAG WERNER DIPL CHEM DR

IPC: C09D5/23 ,  G11B5/708 ,  G11B5/84 ,  G11B5/68

Abstract: Aluminium or Al alloy discs coated with a magnetic layer contg. 3-9, pref. 4-6 wt.% corundum powder, where pref. 40-60 wt.% of the corundum has a particle size of 110-200% of the thickness of the final ground magnetic layer, the remainder having a size =110% of this thickness. A corundum paste is prepd. by mixing sharp-edged corundum, size 1-10 mu with an epoxy resin having an epoxide equiv. wt. of 1000-2000 made from epichlorohydrin and 2,2-bis(4-hydroxyphenyl)-propane dissolved in toluene and ethylene glycolmonoethylether-monoacetate (I) to form a resin soln. (II). This paste is added to a mixt. of needle-shaped gamma Fe2O3 (average particle length 0.8 mu) with a further amt. of (I) and (II) plus a hardenable melamine-formaldehyde and sprayed on one or both sides of the Al disc (which may first be coated with a laquer) to form a film 3.9-4.4 mu thick. After curing, the surface is ground with rotating discs of porous polyvinyl alcohol sponge using diamond powder (7 mu) and a press. of 0.4 kg/cm2, followed by polishing with felt and diaminod powder (1) mu). The final magnetic layer is 3.8-4.1 mu thick.