公开(公告)号：JPH06198700A

公开(公告)日：1994-07-19

申请号：JP25071893

申请日：1993-10-06

Applicant: BASF MAGNETICS GMBH

Inventor： GEERUHARUTO HIYUBURAA ,  BUORUFUUDEIITAA SHIYUREEAA ,  RAINHARUTO KURECHIYUMAA ,  YOOZEFU SHIERUBURE

IPC: B29C47/02 ,  B05C9/06 ,  G11B5/848

Abstract: PURPOSE: To manufacture a double layer by a wet lap coating method using an extrusion coating machine capable of extremely thinly applying an upper layer containing a magnetizable pigment and a lower lay capable of pref. containing a non-magnetic additive increasing conductivity or reducing light permeability. CONSTITUTION: At least two slot dies for stacking a plurality of layers to apply them to a soft non-magnetic base material by a wet-on-wet system are provided and the upper lip of the common outlet orifice of the slot dies is set back from the lower lip thereof. A magnetic recording medium is produced by an extrusion coating machine constituted so that a right parallelepiped magnet of which the upper end is opposed to an extruder orifice at a distance of 0.1-5 mm is arranged behind a base material in parallel thereto and an uppermost magnetizable layer has a dry thickness of 2.0 μm or more and the lower layer adjacent thereto, pref., a non-magnetic layer has a dry thickness of 0.5 μm or less.

公开(公告)号：JPH0899344A

公开(公告)日：1996-04-16

申请号：JP13157595

申请日：1995-05-30

Applicant: BASF MAGNETICS GMBH

Inventor： ZUIIKUFURIITO RIIGAA ,  RAINHARUTO KURECHIYUMAA ,  FURANTSUUKUSAFUAA BUAAGUNAA

IPC: B29C48/345 ,  B05C9/06 ,  G11B5/845 ,  G11B5/848 ,  B29C47/30

Abstract: PURPOSE: To provide an extrusion forming apparatus of a magnetic layer capable of forming a layer free from a streak even if the formed layer is extremely thin without bringing about the mixing of both wet layers after a magnetic powder dispersion is applied to a magnetic layer support sheet. CONSTITUTION: In an extrusion forming apparatus of a magnetic layer having extrusion slits 8, 8' at least at two places and characterized by that the center line between these slits stands erect with respect to the surface of a layer support sheet and the front surface 15 of the separator 16 between both slits is an obliquely downwardly inclined surface, the edge 5 of a magnet 2 is arranged behind the layer support sheet in opposed relation to an extrusion opening and a magnetizable layer is formed while extruded from the extrusion opening 3 and the edge 5 of the magnet 2 is positioned at the height level of the common extrusion opening of both slits.