Abstract: Provided is a magnetic recording medium suited to magnetic recording and reproduction systems employing linear methods and incorporating magnetoresistive reproduction heads. The magnetic recording medium comprising a magnetic layer for servo signal recording, a nonmagnetic layer, and a magnetic layer for information recording in this order on a nonmagnetic support, wherein said magnetic layer for information recording exhibits a coercivity of at least 7.96 kA/m (100 Oe) higher than a coercivity of said magnetic layer for servo signal recording and an interface roughness at the interface of said magnetic layer for servo signal recording and said nonmagnetic layer ranges from 7 to 12 nm.

Abstract: A magnetic recording medium comprising a support having provided on one side thereof a magnetic layer containing a ferromagnetic powder and a binder, wherein the magnetic layer surface has protrusions having a height of from 20 to 50 nm in the number of from 20 to 150 per 900 &mgr;m2 of the surface, and a magnetic recording medium comprising a support having provided thereon a magnetic layer containing a ferromagnetic powder and a binder, wherein the magnetic layer surface has the following protrusion distributions of the protrusion heights: protrusion number a of protrusion height of region A (20 nm or more and less than 30 nm) accounts for from 52.5 to 92.5% (A), protrusion number b of protrusion height of region B (30 nm or more and less than 40 nm) accounts for from 9 to 29% (B), and protrusion number c of protrusion height of region C (40 nm or more) accounts for from 0 to 18.

Abstract: Provided is a magnetic recording medium suited to magnetic recording and reproduction systems employing linear methods and incorporating magnetoresistive reproduction heads. The magnetic recording medium comprising a magnetic layer for servo signal recording, a nonmagnetic layer, and a magnetic layer for information recording in this order on a nonmagnetic support, wherein said magnetic layer for information recording exhibits a coercivity of at least 7.96 kA/m (100 Oe) higher than a coercivity of said magnetic layer for servo signal recording and an interface roughness at the interface of said magnetic layer for servo signal recording and said nonmagnetic layer ranges from 7 to 12 nm.

Abstract: A nut-fixing part 20 formed in a housing 10 has a nut-holding room 26, where a nut 30 is insertable and detachable by a movement in a direction perpendicular to the thickness direction of the nut 30. At the entrance of the nut-holding room 26, a projection 27 is provided to prevent the inserted nut 30 from sliding out. By this construction, this type of connector can be miniaturized further. In addition, when this connector mounted on a circuit board is heated in a furnace for soldering electrical connections, even if the housing experiences a stress relief, there is no possibility of any nut falling off from the housing.

Abstract: A magnetic recording tape favorably employable for computer data storage has a flexible polymer web, a magnetic recording layer arranged on one surface side of the web, and a backing layer arranged on another surface side of the web, characterized in that the recording tape has a thickness of 2 to 8 .mu.m and shows a Young's modulus of not less than 1,200 kg/mm.sup.2 in its longitudinal direction; and the backing layer has a thickness of 0.2 to 1 .mu.m and is composed of a binder, a carbon black, a non-magnetic powder I having Mohs' scale of hardness of 3 to 4.5 and another non-magnetic powder II having Mohs' scale of hardness of 5 to 9. Between the magnetic layer and the flexible polymer web, a non-magnetic undercoating layer composed of a binder and a non-magnetic powder can be provided.

Abstract: An electrical connector has an insulative housing, a fixture, and a shield. The fixture is used for fixing this insulative housing on a circuit board, and the shield is to cover the insulative housing. The insulative housing, which is made of an electrically insulating material, comprises a main body and an engaging portion, which protrudes forward from the main body to engage with a matable connector. The insulative housing also comprises fixture retaining slots, which extend through the main body in the vertical or to-and-fro direction at the lateral ends of the main body of the housing. Into each of these fixture retaining slots, a fixture, which is made of an electrically conductive metallic material, is press-fit to fix the insulative housing onto a circuit board. The shield, which is made of an electrically conductive metallic material, comprises a peripheral portion and contact portions in a one-piece body.

Abstract: A novel magnetic recording medium is provided comprising a non-magnetic support having provided thereon a magnetic layer comprising a ferromagnetic powder dispersed in a binder, wherein at least one fatty acid amide compound represented by formula (I), at least one fatty acid ester represented by formula (II) and at least one fatty acid ester represented by formula (III) are provided in or on the magnetic layer: ##STR1## wherein R.sup.1 represents a C.sub.13-21 straight-chain saturated hydrocarbon group; ##STR2## wherein R.sup.2 represents a C.sub.12-21 straight-chain or branched saturated or unsaturated hydrocarbon group; and R.sup.3 represents a C.sub.1-10 straight-chain or branched saturated or unsaturated hydrocarbon group; ##STR3## wherein R.sup.4 represents a C.sub.12-21 straight-chain or branched saturated or unsaturated hydrocarbon group; R.sup.5 represents a C.sub.2-3 divalent hydrocarbon group; R.sup.6 represents a C.sub.

Abstract: A magnetic recording medium comprising a non-magnetic support having provided thereon a magnetic layer comprising a ferromagnetic powder dispersed in a binder,wherein said binder comprises a polymer containing a polar group selected from --SO.sub.3 M, --OSO.sub.3 M, --COOM, ##STR1## where M represents a hydrogen atom, Li, Na, K or NR.sub.4 where R represents a hydrogen atom or an alkyl group, and M' represents a hydrogen atom, Li, Na, K, an alkyl group or NR.sub.4 where R represents a hydrogen atom or an alkyl group, andsaid magnetic layer contains at least one fatty acid ester compound represented by formula (I), at least one fatty acid ester compound represented by formula (II), and at least one fatty acid having from 11 to 35 carbon atoms: ##STR2## wherein R.sup.1 represents a linear or branched chain hydrocarbon group having from 11 to 35 carbon atoms, R.sup.

Abstract: A method for preparing a magnetic recording medium comprising a non-magnetic support having coated thereon a magnetic layer of a magnetic coating composition containing ferromagnetic metal particles and a binder, comprising at least (1) a step of mixing and dispersing ferromagnetic metal particles, a binder, and a solvent to prepare magnetic coating composition, (2) a step of adding and mixing lubricating agent therewith and (3) a step of coating the resulting magnetic coating composition on a non-magnetic support.

Abstract: A magnetic recording medium comprising a non-magnetic support having provided thereon an intermediate layer comprising carbon black, a binder and ferromagnetic particles in a weight ratio of from 5% to 25% based on the carbon black; and a magnetic layer provided on said intermediate layer, wherein said magnetic layer comprises ferromagnetic particles and a binder.

Abstract: A magnetic recording medium contains in its magnetic recording layer a ferromagnetic metal powder containing an aluminum component in an amount of 1 to 6% by weight as alumnum metal, and an extremely hard abrasive such as .alpha.-alumina, chrome oxide, silicon carbide and silicon nitride. A magnetic recording medium preferably contains in its magnetic recording layer a binder comprising a resin component having a polar group.

Abstract: A magnetic recording medium comprising a nonmagnetic support and a magnetic recording layer provided on the support, said magnetic recording layer comprising a binder and a ferromagnetic powder dispersed therein, which is characterized in that said binder is composed of a resin component comprising:a vinyl chloride copolymer containing a repeating unit having at least one polar group selected from the group consisting of --SO.sub.3 M, --OSO.sub.3 M, --COOM and --PO(OM').sub.2, wherein M is hydrogen or an alkali metal atom, and M' is any one of hydrogen, an alkali metal atom and a lower hydrocarbon group, and a repeating unit having an epoxy group; anda polyurethane resin containing a repeating unit having at least one polar group selected from the group consisting of --SO.sub.3 M, --OSO.sub.3 M, --COOM and --PO(OM').sub.2, wherein M and M' have the same meanings as defined above.

Abstract: In a magnetic recording medium such as a video tape comprising a nonmagnetic support and a magnetic recording layer provided on the support, said magnetic recording layer comprising a binder and a ferromagnetic powder dispersed therein, the improvement in which:the magnetic recording layer comprises a fatty acid ester lubricant and a lubricant other than the fatty acid ester lubricant;the binder is composed of a resin component comprising a resin containing a repeating unit which has a polar group and having a glass transition point of not lower than 50.degree. C., and a resin containing a repeating unit which has a polar group and having a glass transition point of lower than 50.degree. C; andat least one resin of the resins contains a repeating unit having a polar group such as --SO.sub.3 M, --OSO.sub.3 M or --PO(OM').sub.2, wherein M is hydrogen or an alkali metal atom, and M' is hydrogen, an alkali metal atom or a lower hydrocarbon group.

Abstract: A tape for cleaning magnetic head comprising a support and a cleaning layer coated on at least one surface of said support, which is characterized in that said cleaning layer contains a ferromagnetic metal powder as abrasive, the surface of said cleaning layer is a surface of center line average height of not less than 0.025 .mu.m as cut-off value of 0.08 mm, and said tape has a stiffness of not more than 2.

Abstract: A magnetic recording medium comprising a non-magnetic support having coated thereon a magnetic layer, the magnetic layer containing (i) ferromagnetic alloy particles having an average length in the long axis of 0.25 .mu.m or less and (ii) fatty acid components comprising behenic acid in an amount of 20 to 75 wt%, stearic acid in an amount of 10 to 45 wt% and oleic acid in an amount of 10 to 45 wt% based on the total weight of the three fatty acids.

Abstract: A magnetic recording medium is disclosed which comprises a non-magnetic support having provided thereon a magnetic layer containing ferromagnetic metal particles and a binder, wherein the ferromagnetic metal particles have a specific surface area of 30 m.sup.2 /g or more, and a saturation magnetization of 120 emu/g or more and have been surface-treated with an organic compound. Also, a magnetic recording medium is disclosed which comprises a non-magnetic support having provided thereon a magnetic layer containing ferromagnetic particles and a binder, wherein the ferromagnetic particles have been surface-treated with an organic compound and the binder has essentially no functional groups which adsorb onto ferromagnetic metal particles.

Abstract: A heat-treating process is disclosed. The process involves cutting a polymer support for a recording medium from a web roll of a long support base into a sheet form. The sheet or sheets in a superposed state are then heat-treated while applying pressure in the range of 1 g/cm.sup.2 to 1 kg/cm.sup.2 at a temperature of 50.degree. C. to 150.degree. C. for a period of time of 15 seconds to 24 hours. The heat treating process avoids conventional problems with respect to thermal shrinkage.

Abstract: A tape for cleaning magnetic head comprising a support and a cleaning layer coated on said support which contains an abrasive comprising a ferromagnetic metal powder of a specific surface area in the range of 40 to 65 m.sup.2 /g as a principal component, the surface of said cleaning layer having a surface of center line average height in the range of 0.02 to 0.04 .mu.m at a cut-off value of 0.08 mm.

Abstract: A flexible magnetic disc for use in combination with a magnetic head assembly which includes a regulator plate and performs magnetic recording or playback by protruding a magnetic head beyond a predetermined support level of a rotatable sheet of magnetic recording medium at least by an amount which is substantially equal to a total thickness of the recording medium. Assuming that the recording medium has a total thickness of t millimeters (mm) and a Young's modulus of E grams per square millimeter (g/mm.sup.2), a product of the Youngs's modulus E and the third power of the total thickness t, i.e. Et.sup.3, lies in a range between a lower limit of 2.5 g.mm and an upper limit of 36 g.mm inclusive of the lower and upper limits.

Abstract: A magnetic recording medium is described, comprising a non-magnetic support having provided thereon a magnetic layer comprising ferromagnetic particles dispersed in a binder, said ferromagnetic particles having a BET specific surface area of 25 m.sup.2 /g or more, said binder comprising a modified polyurethane resin containing 0.1 meq/g or more of functional groups selected from carboxyl groups, hydroxyl groups, sulfonic acid groups, and epoxy groups, and containing at least three functional groups per molecule of the resin.