Abstract: An improved extrusion coater having at least two coater slots for applying one or more magnetizable layers to a flexible nonmagnetic substrate is described. The upper lip of the outlet orifice is recessed relative to the lower lip and, in addition, the edge of a right parallelepiped magnet which has a gradient of more than 400 A/cm.sup.2 in the direction of the extruder slot, resulting in a stabilized liquid cushion, is arranged opposite the outlet orifice for the dispersions from the extrusion coater, on the other side of the substrate. It is thus possible to apply very thin layers and to make the meniscus insensitive to interfering forces. To reduce the edge bead, a stripping plate (13) which is extended beyond the range of the upper or lower lip of the extrusion coater, in the direction of the coated material web (1), is mounted at both coating edges, a minimum distance of from 0.05 to 0.8 mm between the surface (19) of the stripping plate (13) and the coated material web being established (FIG. 1).

Abstract: A wet-on-wet application process by means of a sheet extruder having at least two slot dies is described, the upper layer containing metal powders and/or metal powder alloys while the lower layer contains the same magnetic pigments and conductivity-increasing and/or transparency-reducing additives, preferably carbon black, and both layers having virtually the same rheological properties. The magnetic recording medium has improved conductivity and very good running behavior, in particular when used as a mirror mastertape.

Abstract: A magnetic tape cassette, for example an audio cassette, which is distinguished by an attractive outer appearance, consists of a bottom part and a top part, transparent in each case, and contains inside it two adjacent tape rolls. The bottom part and the top part each have a transparent housing wall having transparent or slightly colored regions and opaque or untransparent regions. The untransparent or opaque regions are produced by printing surface areas of the cassette housing walls including the application of various patterns and/or colors.

Abstract: A magnetic tape cassette, in which the activation of the front flap (11) and of the slide (15) is coupled by cassette-side means, contains a side part (12) of the front flap provided with a recess (20) in which a guide peg (18), which rests in the sidewall (16) of the slide, engages with the recess and thus couples the swivelling movement of the front flap with the sliding movement of the slide. In another embodiment, the side wall (12) of the front flap (11) contains a guide peg (22) which engages with a recess (21) provided in a side wall (16'') of the slide (15) (FIG. 3, FIG. 5).

Abstract: A magnetic tape cassette, particularly a video tape cassette which is provided with a hinged front panel prestressed by a tension spring, the coil of which is positioned on an axle on the inside of the side wall of the front panel. The free end of the long spring leg grips beneath the front of an upper housing half of the cassette, which constrains the long spring leg. A lower housing half has a hinged locking plate on the inside, in the area of the front panel. The locking plate has a obliquely extending projection projecting over the plate, which projection being eccentric to the center of rotation of the plate has a surface off set from the axis of rotation of said hinged locking plate, and on the surface of oblique projection the long spring leg stressed between the upper housing half and the projection of the plate to produce a moment of force on the plate tending to swing the plate on the axis of rotation.

Abstract: A locking plate for front panels of magnetic tape cassettes, particularly video tape cassettes, which has a hinged bearing and contains a spring which exerts a torque in a direction towards the barred position, whereby the plate spring is injected on the journal bearing of the locking panel pointing inside the casette and is U-shaped and that its free end touches the wall of the cassette housing.

Abstract: A video cassette with two reels which are arranged in plane-parallel fashion for winding and unwinding a magnetic tape and with a locking mechanism consisting of a pivotal two-armed pawl for each reel which can be slipped on a support. One lever arm engages in a toothed reel flange in the inoperative position of the cassette and the other lever arm rests on the disengaging component of a vertically rotatable release lever. The locking mechanism also includes moulded pre-tensioning arms, the deflection points of the pre-tensioning arms rigid with the housing at the support lie close to the rotational axis of the pawl.

Abstract: A cover for the light channel for a device for switching-off at the end of its run a magnetic cassette tape with a transparent leader tape, an opening being provided in the bottom part of the cassette for accommodating the light, the opening being defined by a one- or two-part light shaft having slotted light channels for the passage of the beams of light towards the light-receiving elements on the side of the device, the light shaft 5 located only in the bottom part of the cassette being provided with an encircling ledge 8 below the light channels, 6, 7 on which ledge a flexible piece of film 9 rests which is transparent at least in the region of the light channels, or the light shaft, which is divided in the middle and fills out the height of the interior of the cassette housing, has an encircling ledge 8, 10 in each of the top and bottom parts 5, 5 a thereof, outside the region of the light channels, between which a flexible transparent piece of film 12 covering the light channels rests, the piece of film

Abstract: Magnetic tape cassette for magnetic recording and play-back devices with pivotal front lid whereby the front lid is biassed by a two-armed safety bar which may be moved forwards and backwards, the swivel range of which is restricted by a pin on the inside of the front lid, characterized in that the two-armed safety bar 19 extends beyond its bearing journal 22, and the extension in the closed position of the front lid serves as a stop 25 on the wall 27, positioned behind, on the upper part of the cassette, and an U-shaped leaf spring 28 is provided to bias the safety bolt between the back wall of the safety bar bearing 18 and the adjacent safety bar arm 21.

Abstract: Magnetic tape cassette for magnetic recording and playback devices, comprising a substantially rectangular, two-part housing which has an upper main wall and an opening along its front side, along which the magnetic tape is transported from two plane-parallel positioned reels, and a pivotal front lid which partly overlaps the side walls and which release and closes the opening, and which comprises an outer cover and an inner cover by which the magnetic tape is enclosed in the closed position of the front lid being biassed by means of torsion springs, one of the pivot pins 12 on the inside wall of the side part 10a of the front lid 7 accomodating a one-armed flat spiral spring 13, the arm 16 of which, pointing towards the front lid, has a length which extends up to the outer cover 8 of the front lid, and the arm in the ready made cassette lies in a groove 18 on the front end of the upper part of the cassette.

Abstract: This invention relates to a spool for video cassettes comprising at least one flange which is raised from or deposited onto the base of the cassette against the force of a spring. The spool has a hollow-cylindrical projection (11) which is open to the outside, in the center of the top of the spool hub, in which projection (11) a spherical body (12) of abrasion-proof plastics material is clamped, for example, polyoxymethylene. The spherical cap protruding from the projection protrudes beyond other pins (10) which are optionally moulded on the surface. The spool itself is made of a different, plastics material of less hardness compared with that of the spherical body.

Abstract: Elimination of beads created along the edge during coating magnetic binder containing dispersions on a flexible support by subjecting the coated dispersion to the stray field of a magnetic circuit consisting of permanent magnets and soft magnetic conductor elements, the central line of the gap of the magnetic circuit extending downstream the moving support at an angle up to 10.degree. in the direction towards the border of the support.