Abstract: Provided is a thin magnetic tape with good tracking and very little output variation in VTRs. The magnetic tape comprises a flexible support, a magnetic layer provided on one side of said flexible support and a backcoat layer provided on the reverse side of said flexible support. The magnetic tape has a stiffness equal to or less than 70 mg·mm2 in the width direction, an average meandering amount of a tape edge trajectory traced by each of both end in the width direction of said tape observed from the direction perpendicular to said magnetic layer surface is equal to or less than 15 &mgr;m in every end, and an intensity of a meandering component having a cycle of 20 to 200 mm is equal to or less than 30 percent of the intensity of a meandering component having a cycle of 20 to 10,000 mm.

Abstract: A magnetic recording medium is provided which includes a non-magnetic support and a magnetic layer formed on or above the support. The magnetic layer includes a ferromagnetic powder, a binder resin, an abrasive, and a fatty acid ester. The fatty acid ester is a fatty acid alkyl ester compound having an acid hydrolysis rate of 0.030 (1/hr) or less.

Abstract: A magnetic recording medium is formed from a non-magnetic support, and a magnetic layer formed on the support and including mainly a binder resin and a ferromagnetic metal powder including mainly Fe. The magnetic layer includes an abrasive and a lubricant. The abrasive present on the surface of the magnetic layer satisfies the relationship 0.01≦H15/H10≦0.3 where H10 denotes the number of particles per unit area having a height less than 10 nm (particles/&mgr;m2) and H5 denotes the number of particles per unit area having a height equal to or greater than 15 nm (particles/&mgr;m2). The magnetic recording medium has a surface lubricant index of 3 to 11. The height of the abrasive particles can be controlled by, for example, a blade treatment using an abrasive tape (LTBL system) or a diamond powder-studded rotating roll (DWBL system).

Abstract: A magnetic recording medium having little head staining and favorable dropout and error rates when recording after extended or high-temperature and -humidity storage. The medium has, on a nonmagnetic support, a magnetic layer of coated ferromagnetic metal powder containing Fe and binder. The ferromagnetic metal powder contains at least Al, Co and Y, and, respectively, has ratios of Al to Fe (Al/Fe) ranging from 5 to 15% by atom, Co to Fe (Co/Fe) from 1 to 25% by atom, and Y to Fe (Y/Fe) ranging from 0.5 to 5% by atom. Si and Nd either are absent or are each found in an amount not more than 0.01% by atom with respect to Fe. The magnetic layer contains a fatty acid and a fatty acid ester, the fatty acid ester being a fatty alkyl ester compound having an acid-hydrolytic speed not more than 0.

Abstract: Provided is a thin magnetic tape with good tracking and very little output variation in VTRs. The magnetic tape comprises a flexible support, a magnetic layer provided on one side of said flexible support and a backcoat layer provided on the reverse side of said flexible support. The magnetic tape has a stiffness equal to or less than 70 mg.mm2 in the width direction, an average meandering amount of a tape edge trajectory traced by each of both end in the width direction of said tape observed from the direction perpendicular to said magnetic layer surface is equal to or less than 15 &mgr;m in every end, and an intensity of a meandering component having a cycle of 20 to 200 mm is equal to or less than 30 percent of the intensity of a meandering component having a cycle of 20 to 10,000 mm.

Abstract: A magnetic recording medium is provided comprising a non-magnetic support and at least one magnetic layer comprising ferromagnetic metal particles principally containing iron, having a spindle shape and having an average major axis length of 0.15 &mgr;m or less, and a binder resin, and optionally further comprising, between the support and the magnetic layer, at least one adhesive layer or at least one non-magnetic layer principally containing a non-magnetic inorganic powder and a binder, and wherein center line average surface roughness Ra of the magnetic layer surface being 2 to 6 nm, said recording medium having the following properties; steel ball wear at 23° C. and 70%RH being 2×10−5 to 4×10−5 mm3, surface C/Fe ratio measured by Auger electron spectroscopy being 50 to 100, and coefficient of friction between the magnetic layer surface and an SUS rod having a roughness of 8 to 10 nm being 0.2 to 0.3.

Abstract: A process is disclosed for making para-aramid filaments of especially high strength by extruding a solution of para-aramid through fine capillaries and drying the resulting filaments under high tension.

Abstract: A magnetic recording medium is disclosed, comprising a nonmagnetic support having provided on a first side of the support a magnetic layer containing a ferromagnetic powder and a binder, the ferromagnetic powder is a ferromagnetic metal powder having a water-soluble calcium content of 100 ppm or less, and the ratio of widthwise stiffness (TD) to lengthwise stiffness (MD) of the magnetic recording medium is in the range of from 0.65 to 1.00. In a preferred embodiment, the magnetic layer contains a saturated aliphatic acid having 14 to 24 carbon atoms, the magnetic layer has a dry thickness of from 0.5 to 3.5 .mu.m, the nonmagnetic support has a thickness of from 8 to 11 .mu.m, and the magnetic recording medium further comprises a backing layer having a dry thickness of from 0.1 to 1.0 .mu.m.

Abstract: A method for preparing a magnetic recording medium is disclosed, comprising the steps of (1) surface-treating ferromagnetic particles with a glycidyl compound having a molecular weight of 1,000 or less and having an epoxy equivalent of 200 g/eq. or less, (2) dispersing the surface-treated ferromagnetic particles with a binder to prepare a magnetic coating composition, (3) coating the resulting magnetic coating composition on a nonmagnetic support, and then (4) drying the magnetic coating composition.

Abstract: A method for making a magnetic recording medium comprises the steps of mixing ferromagnetic grains and a surface treating agent, grinding the resulting mixture, and thus obtaining a ground mixture. A binder and a solvent are added to the ground mixture, which results from the mixing and grinding process, the resulting mixture is kneaded and diluted, and a kneaded and diluted mixture is thus obtained. An additive and a solvent are then added to the kneaded and diluted mixture, which results from the kneading and diluting process, a dispersion process is carried out on the resulting mixture, and a dispersion mixture is thereby obtained. Thereafter the dispersion mixture, which results from the dispersion process, is applied to a non-magnetic substrate.

Abstract: A method for manufacturing a magnetic recording medium is disclosed, comprising ferromagnetic alloy powders having an average length in the long axis of 0.3 .mu.m or less and a specific surface area (BET Method) of 45 m.sup.2 /g or more, by steps which comprise surface-treating the ferromagnetic alloy powders with at least one triazine thiol compound, dispersing the surface-treated powders in a binder, and then coating the binder containing the surface-treated powders on a nonmagnetic support, wherein the ferromagnetic alloy powders are surface-treated with a triazine thiol compound represented by formula (I) in a condition in which the moisture content of the ferromagnetic alloy powders is 0.5 wt % or less, in a system of substantially excluded moisture: ##STR1## wherein R represents R.sub.1 O--, R.sub.1 S--, R.sub.1 NH--, or R.sub.1 R.sub.2 N--R.sub.1 --, R.sub.1 and R.sub.