Abstract: A magnetic recording medium which comprises a non-magnetic support having on the surface side thereof a magnetic recording layer and on the opposite side thereof a backing layer is disclosed. The backing layer contains carbon black and a binder and has a thickness of 2 .mu.m or less. The carbon black is composed of fine-grained carbon black having a mean grain size of 10 to 30 m.mu. and coarse-grained carbon black having a mean grain size of 100 to 150 m.mu.. In the backing layer the ratio of the content of carbon black to the binder ranges from 1:0.5 to 1:3.5 by weight.

Abstract: A magnetic recording medium including a nonmagnetic support having a magnetic layer on one side thereof and a backing layer on the opposite side thereof, said backing layer comprising a fatty acid having 12 or more carbon atoms and copper or copper ions. Fatty acid is saturated or unsaturated, and copper is 0.2 micron or less in size.

Abstract: A novel magnetic recording medium comprising a non-magnetic support, a magnetic recording layer, and an intermediate layer containing an electroconductive polymer. An optional second intermediate layer contains carbon black and is provided on either surface of the first intermediate layer. The magnetic recording medium has low surface electric resistance, and when used as a video tape, has both a high video S/N ratio and improved stability of video S/N with the passage of time.

Abstract: A magnetic recording medium is disclosed. The medium comprises a non-magnetic support having provided on opposite surfaces a magnetic recording layer and a backing layer containing two types of carbon black and a binder and having a thickness of 2 .mu.m or less, one of said carbon black being fine carbon black having an average particle size of 30 to 100 m.mu. and the other of said carbon black being coarse carbon black having an average particle size of 150 to 500 m.mu., and the mixing weight ratio of said carbon black and the binder being 1:1.5 to 1:3.5.

Abstract: A magnetic recording medium which comprises a non-magnetic support having on the surface side thereof a magnetic recording layer and on the opposite side thereof a backing layer having a thickness of 2 .mu.m or less, which contains carbon black and a binder and optionally, an inorganic powder, in which the backing layer contains at least two kinds of carbon black, one being fine-grained carbon black having a mean grain size of 10 to 30 m.mu. and the other being coarse-grained carbon black having a mean grain size of 150 to 500 m.mu. such that the weight ratio (P/B) of the total amount of carbon black and inorganic powder (P) to binder (B) is from about 1/0.5 to 1/3.5. The recording medium described provided smooth and stable tape-running for an extended period and a high S/N ratio.

Abstract: A magnetic coating composition comprising a binder dissolved in a solvent and magnetic grains dispersed therein is applied onto a surface of a non-magnetic substrate continuously moved. The coating film thus overlaid on the non-magnetic substrate is subjected to a preliminary orientation step for orientating the magnetic grains in the coating film, and then to a preliminary drying step. A final orientation step is then conducted while intermediate drying is carried out. Thereafter, final drying is effected.

Abstract: A process for the production of magnetic recording media including a nonmagnetic support having a magnetic layer on one side thereof, and a backing layer obtained by dispersing a filler in a binder on the other side thereof, in which said backing layer is provided by:a first step of kneading and dispersing a filler and a binder by means of a roll mill to form chips,a second step of dissolving said chips in a solvent followed by dispersion effected with a sand grinder, anda third step of adding a curing agent to the obtained liquid dispersion, followed by coating.

Abstract: The present invention relates to a leader or trailer tape for a magnetic tape, which comprises a plastic support member and, on one side thereof, a laminated coating consisting of at least (1) an electrically conductive layer as a first layer and (2) a layer containing mainly a pigment and a binder as a second layer.

Abstract: A magnetic recording medium with a greatly reduced coefficient of friction comprising a non-magnetic support having thereon a magnetic recording layer comprising finely divided ferromagnetic powders in a binder, wherein(1) at least one alkylpolysiloxane having a hydrophilic group in the side chain thereof and represented by the formula (I) ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different, each represents ##STR2## provided that R.sub.1 and R.sub.2 are not simultaneously --CH.sub.3 ; R.sub.3 represents --CH.sub.3 or the aliphatic chain having 10 to 18 carbon atoms of a saturated or unsaturated fatty acid; R.sub.4 represents --H or --CH.sub.3 ; Z represents an ionic group, which renders the alkylpolysiloxane water-soluble, selected from the group consisting of --OSO.sub.3 Na, --COOR.sub.5 wherein R.sub.

Abstract: This invention relates to a leader or trailer for a magnetic tape, which comprises a plastic support member, a coated layer consisting essentially of a pigment and binder on the surface of the plastic support and a lubricant layer on the back side of the plastic support, the pigment consisting of a mixture of at least two solid powders each having a mean grain size of (A) 0.002 to 3 microns and (B) 5 to 35 microns and the lubricant layer being coated in a proportion of at least 0.1 mg/m.sup.2.

Abstract: A cleaning tape used for cleaning the surface of a magnetic recording head of a tape recorder or the like consists of a substrate and a cleaning layer. The cleaning layer contains two kinds of particles. One kind of particles has a small diameter and a high hardness, and the other has a large diameter and a low hardness.

Abstract: In a magnetic recording substance comprising a magnetic recording layer on one side of a non-magnetic support and a back layer on the other side thereof, the back layer is provided by coating a powdered solid with a binder and coating solvent and having spike grains with a height of 0.8 to 5 microns and an interval or pitch of at least 200 microns on the surface thereof and a friction coefficient of at least 0.25.