Abstract: A magnetic recording medium comprises a nonmagnetic substrate and at least one ferromagnetic metal layer applied thereon and a protective layer formed on this metal layer and consisting of a compound which consists of an unfluorinated or partially fluorinated alkyl radical and a disulfide, hydroxyl or keto group.

Abstract: A container for at least two separate articles with separate receiving spaces, the dividing wall being movable and it being possible as a result to vary the momentary size of the receiving spaces, thereby also facilitating the accessibility and removability of the articles. The container can be suitably used for any type of articles, in particular for recording carriers and insert sheets.

Abstract: A description is given of a cuboidal multipack for vertically stacked magnetic recording media, comprising a rectangular pallet, a baseplate and top plate and wound roll sets stacked between two intermediate plates in each case, the tape rolls being wound up on flangeless winding hubs provided with internal bores, through which a hub sleeve is inserted, the pack being protected by edges and side parts and a stretch film being drawn around the entire unit. To be able to stack a large number of wound rolls one on top of the other without the risk of damaging the edges of the tape rolls, each intermediate plate, which is provided on its upper side and under side with a ring groove, is supported by means of the end face of the hollow-cylindrical hub sleeve by the next-lower intermediate plate, so that merely the wound pack accommodated in one set is placed with its weight able to bear on an intermediate plate.

Abstract: A magnetic dispersion comprising finely divided iron power or iron alloy powder having a BET value of more than 35 m.sup.2 /g dispersed in a polymeric binder and organic solvent, whose filterability is markedly improved, is obtained by using certain low molecular weight phosphoric esters of the general formula I or II ##STR1## combined with a dispersion-active compound which contains at least one polar group capable of adsorption on the magnetic pigment. The polar group of the dispersion-active compound can be an acid or alkaline or amphoteric group or a group capable of hydrogen bonding or polarization. The dispersion-active compound can be a polycondensate, a polyaddition product or a chain growth copolymer which can also be used in the magnetic dispersion combined with customary other polymeric binders.

Abstract: Magnetic recording media consist of a nonmagnetic substrate and at least one magnetizable layer which is firmly applied thereon is based on a magnetic material dispersed in at least one polyureaurethane and a polyurethaneurea (meth)acrylate, the polyurethaneurea (meth)acrylate being obtained by reacting a polyacrylate with a mixture of di- and polyisocyanates and converting the remaining NCO groups into substituted urea groups with aminoalkyltrialkoxysilanes.

Abstract: A wet-on-wet application process by means of an extrusion coater having at least two slot dies is described, the upper lip of the common outlet orifice of the slot dies being recessed relative to the lower lip and a right parallelepiped magnet whose upper edge is opposite the extruder orifice at a distance of, preferably, from 1 to 1.5 mm away being arranged on the other side of the nonmagnetic substrate and parallel to the latter, in which the uppermost layer contains magnetic pigments and has a layer thickness of more than 2.0 .mu.m while the lower layer is nonmagnetic, may contain a conductivity-increasing additive or nonmagnetic fillers and has a thickness of less than 0.5 .mu.m when dry. The magnetic recording medium has very good mechanical and electroacoustic properties, improved conductivity, very good adhesion, improved surface quality and a smaller number of dropouts.

Abstract: Flexible magnetic recording media consisting essentially of a web-like nonmagnetic substrate, a magnetic layer applied to one main side of the web-like substrate and a backing layer formed on the opposite main side of the substrate from a polymeric binder, at least one filler, at least one auxiliary pigment and a polyolefin having a spherical particle shape.

Abstract: Sheet-like PET materials having slight surface roughness consisting of fine dot patterns in the submicron range are produced by double successive exposure of the surfaces to polarized UV light produced by a pulsed excimer laser and having planes of polarization arranged at an angle of from 20.degree. to 90.degree. relative to one another, and the PET films treated in this manner are used as a substrate for thin ferromagnetic metal layers.

Abstract: In the preparation of dispersions of magnetic pigments in organic solvents, dispersants which have a sterically stabilizing effect are used. Milling results in division of the pigment aggregates, which combine again as a result of attractive forces to give secondary agglomerates in the event of poor stabilization. These flocculating materials must be removed from the dispersion by expensive filtration. If an increase in the fineness or pigment batch fluctuations lead to an increase in the secondary agglomerates, filter breakthroughs may occur, resulting in a dramatic reduction in the yield of magnetic recording medium. It was found that excellent dispersion stability is achieved when the magnetic pigments are first precoated with a long-chain dispersant. Subsequently, the use of charge-generating, low molecular weight codispersants, a charge build-up on the pigment is specifically induced by means of bases or acids.

Abstract: A hollow-cylindrical supporting core for pancakes which is produced from recyclable plastic by injection molding is described, the arms, which may be angled off, which extend from the gating point and run to the inside diameter of the supporting core remaining in place after demolding of the injection mold and being suitable as holding grips for the supporting core.

Abstract: A magnetic recording medium comprising a nonmagnetic substrate and at least one magnetic layer applied thereon and containing an acicular chromium dioxide uniformly distributed in a polymeric binder and additives and having a coercive force of at least 60 kA/m, a mean particle length of the chromium dioxide of less than 300 nm, whose factor HD according to the formula ##EQU1## where KT is the coercive force of the magnetic layer in [kA/m], measured in an external field of 380 kA/m, L is the mean particle length and .DELTA.L is the range of the particle size distribution, determined from the numerical distribution of the particle length, both measured in [nm], is greater than 1.85, and a process for the preparation of this chromium dioxide.

Abstract: A compact cassette is provided with substantially rectangular plastic support liner(s) between tape roll(s) and cassette wall(s), having at least one longitudinal bend, and the deflections of the support liners in a defined load range should be not more than a factor of 2 greater in the case of exposure to heat at about 85.degree. C. compared with no exposure. Suitable liner materials are those having glass transition temperatures equal to or greater than 85.degree. C., for example consisting of polysulfones, polyethersulfones, polyarylether ketones, polyetherimides, and/or blends and/or copolymers thereof.

Abstract: A filter apparatus is described, in which there are in the interior of a filter housing (7) a multiplicity of filter elements (1) which are suspended on the filter cover (3) and in which the inner bores of the filter cartridges are connected to the outlet nozzle (6) via a system of channels. Against the wall of the filter housing (7) there bears a film bag (2), the upper end of which is welded to an O-ring (4), which is seated in an annular groove on the flange of the filter housing, with the diameters of O-ring and film bag being identical. Furthermore, volume displacers (16, 17, 25), which extend in the axial direction over the entire length of the filter housing, are provided between filter bag (2) and inner wall of the filter housing as well as in the inner space of the filter cartridges. When a filter is changed, these volume displacers are, for example, inflated with compressed air, as a result of which the volume of residual filtrate is considerably reduced, so that less loss of dispersion occurs.

Abstract: Parallelepipedal packaging containers, suitable for return transport, for wound-up magnetic recording media, produced from a one-part or multi-part blank having a bottom and top as well as side parts, which are joined to one another by means of foldable joining tabs and containing a hub support extending from the top to the bottom. The bottom and the top each have a circular central clearance through which a one-part or multi-part hollow-cylindrical hub support is inserted, onto which the wound media are fitted in a stackable manner. For assembly of the package from the folded-up state, the hub support has a locking snap-in device on at least one end face.

Abstract: A tensioning device for hubs, comprising a winding shaft having rotatably and drivably mounted on it individual winding elements as hub holder for hubs with inner cylindrical bores, the tensioning device including measures for locking the hubs in the axial direction on each individual winding element, wherein the hub (1) includes along its inner circumference (3), alongside the inner bore (5) and uniformly distributed over the circumference, a multiplicity of resilient elements (2), which have the form of a bent-off arm which extends in the radial direction from the inner circumference (3) of the hub (1) and is bent off in the circumferential direction, the end (4) of each resilient arm being at a distance from the bending point of the next-following arm.

Abstract: A magnetic tape cassette is provided with a raised housing part. The conventional two-part housing of such a cassette is formed by essentially planar housing parts connected to one or more third separate housing parts which can be suitably connected to and/or can connect the planar housing parts. The position of the tape guide elements can be improved for all cassettes of this raised housing part type.

Abstract: In flexible magnetic recording media consisting essentially of a web-like nonmagnetic substrate, the magnetic layer is applied to one main side of the web-like substrate and a backing coating formed on the opposite main side of the substrate from a polymeric binder and nonmagnetic fillers as well as supporting pigments, the backing coating contains a precipitated silica treated on the surface with a phosphate-containing polyurethane.

Abstract: The multipack for pancakes of relatively large diameter comprises two end plates (1, 2) and an intermediate plate (4), anchored on which is a tube (3) on which the pancakes are arranged in series with cushioning disks placed in between. The end plates include fixing means on their narrow sides for stacking a plurality of the multipacks described on top of and next to one another on one and the same pallet. A film of plastic is drawn over each multipack and each multipack is held together by securely lashed straps, which are drawn over the end plates.

Abstract: A right-parallelepipedal multipack for vertically stacked wound rolls, comprising a rectangular pallet (1), a rectangular base plate (3), located on said pallet and provided with a multiplicity of clearances (2), an identically constructed intermediate plate (5) and a likewise identical top plate (6), a multiplicity of wound rolls (4) respectively stacked in-between and means (7, 8, 9) for fixing the pack and the wound rolls, wherein the wound rolls are recording media (10) in tape form which are wound-up on flangeless hubs (11) which are provided with inner bores and through which there is fitted a hub sleeve (8) which is mounted non-displaceably in the clearances (2) of the base plate (3), intermediate plate (5) and top plate (6), and a cover (9), provided with a ring, being adapted to fit onto the upper end of the hub sleeve (8) above the top plate, the lateral four corners of the pack being secured by vertically attached corner parts (7) and a stretch film (12 ) being drawn around the side parts of the pa

Abstract: Flexible magnetic recording media essentially consist of a web-like nonmagnetic substrate, a magnetic layer applied to one main side of the web-like substrate and a backing coating formed on the opposite main side of the substrate from a polymeric binder and nonmagnetizable fillers and supporting pigments.