Abstract: A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording medium is disclosed, comprising a nonmagnetic support having provided thereon at least a lower nonmagnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording medium is disclosed comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

Abstract: A magnetic recording disk having a good overwriting characteristic and an excellent electromagnetic characteristic, as well as superior running durability. The magnetic recording disk comprises a non-magnetic support having coated thereon, in the order, a non-magnetic layer comprising mainly a non-magnetic powder and a binder resin and a magnetic layer comprising mainly a ferromagnetic powder and a binder resin, wherein the magnetic layer is formed by applying a magnetic layer coating solution onto the coated non-magnetic layer while the non-magnetic layer remains in a wet condition, the average thickness of the magnetic layer is 0.5 .mu.m or less, and the maximum thickness and the minimum thickness thereof fall within the range of .+-.15% of the average thickness of the magnetic layer.

Abstract: There is disclosed a flexible magnetic recording disk which is suitable as a high capacity magnetic disk for data recording and has an excellent durability. The flexible magnetic recording disk comprises a non-magnetic support having thereon a non-magnetic layer comprising a non-magnetic powder and a binder resin, and a magnetic layer comprising a ferromagnetic powder and a binder resin, in this order, wherein the magnetic layer has a thickness of 1 .mu.m or less, which is 1/2 or less of the thickness of the non-magnetic layer; and the magnetic layer further contains the abrasive particles which comprise a first abrasive particles having a Mohs' hardness of 6 or more and an average particle size of 0.8 to 1.4 times as large as the average particle size of the magnetic powder and a second abrasive particles having a Mohs' hardness of 6 or more and an average particle size of 2 to 4 times as large as the average particle size of the ferromagnetic powder.

Abstract: A novel magnetic recording disc is provided comprising, a nonmagnetic support having thereon a nonmagnetic layer comprising nonmagnetic particles and a binder resin, and a magnetic layer comprising ferromagnetic particles and a binder resin, in this order. The nonmagnetic particles in the nonmagnetic layer are partially or entirely electrically conductive particles, the thickness of the magnetic layer is in the range of 0.5 .mu.m or less, and the orientation ratio of the ferromagnetic particles in the magnetic layer is 0.85 or more.A novel process for preparing the magnetic recording disc is provided. Further, a novel process for recording and reproduction of a signal having a shortest recordable wavelength of 1.5 .mu.m or less is provided, which utilizes the magnetic recording disc in conjunction with a magnetic head having a gap length (.delta.) of 0.50 .mu.m or less.

Abstract: A magnetic recording disc is disclosed which comprises a disc container with a liner comprising nonwoven fabric in which a flexible magnetic disc comprising a flexible non-magnetic support having on at least one side thereof a magnetic layer mainly comprising a ferromagnetic powder and a binder resin is rotably set, wherein said liner comprises (1) a nonwoven fabric layer mainly comprising rayon fiber on at least the side in contact with the magnetic layer, and (2) a nonwoven fabric layer mainly comprising polypropylene fiber, and said liner comprises from 70 to 80% by weight based on the liner of rayon fiber and from 20 to 30% by weight based on the liner of polypropylene fiber.

Abstract: A magnetic recording medium comprising (A) a non-magnetic support; (B) a non-magnetic layer comprising mainly a non-magnetic powder and a binder resin; and (C) a magnetic layer comprising mainly a ferromagnetic powder and a binder resin, wherein said non-magnetic layer is coated on said non-magnetic support; and said magnetic layer is coated over the previously formed non-magnetic layer while the previously formed non-magnetic layer is still wet; the thickness of the magnetic layer is 0.6 .mu.m or less; the Young's Modulus of the magnetic layer is from 50% to 95% of the Young's Modulus of the non-magnetic layer, and the glass transition temperature of the magnetic layer is lower than that of the non-magnetic layer. The magnetic recording medium has good electromagnetic characteristics and excellent running stability and running durability. It is suitable as a disc medium for high-density recording at a shortest recording wavelength of 1.5 .mu.

Abstract: The present invention relates to a magnetic recording medium comprising, in the following order:(a) a nonmagnetic support;(b) a nonmagnetic layer comprising nonmagnetic particles and a binder resin; and(c) a magnetic layer comprising ferromagnetic particles and a binder resin;wherein said magnetic layer has a thickness of 0.8 .mu.m or less and said nonmagnetic layer and said magnetic layer are formed by a process which comprises the steps of coating a nonmagnetic layer coating solution on said nonmagnetic support, and then subsequently coating a magnetic layer coating solution on said nonmagnetic layer coating solution wile said nonmagnetic layer is wet and, further, wherein the solvent used in said nonmagnetic layer coating solution has a higher boiling point than the solvent used in said magnetic layer coating solution.

Abstract: A magnetic recording disk is disclosed which comprises a flexible magnetic disk comprising a nonmagnetic support having thereon a magnetic layer comprising ferromagnetic powders and binders which is rotatably loaded in a cartridge having a liner formed with a nonwoven fabric on the inside of the cartridge, wherein said liner comprises (A) two layers of a layer of the magnetic layer side comprising a nonwoven fabric of a mixed yarn of rayon fibers and polyester fibers formed on the side which contacts with the magnetic layer, and a layer of the cartridge side comprising a nonwoven fabric of acrylic fibers formed on the side which contacts with the cartridge; or (B) three layers of two layers comprising a nonwoven fabric of a mixed yarn of rayon fibers and polyester fibers, and an inter layer comprising acrylic fibers formed between the two layers.

Abstract: A magnetic recording medium having an improved running durability is disclosed, which comprises a non-magnetic support having formed thereon a magnetic layer mainly composed of a ferromagnetic powder and a binder resin, wherein an ester compound selected from the group consisting of a phthalic acid diester represented by formula (I) and a benzenetricarboxylic acid triester represented by formula (II) is contained in the magnetic layer or coated on the magnetic layer: ##STR1## wherein R.sup.1 and R.sup.2, which may be the same or different, each represents a straight chain or branched alkyl or alkenyl group and the sum of the carbon atoms of R.sup.1 and R.sup.2 is at least 22; and ##STR2## wherein R.sup.3, R.sup.4 and R.sup.5, which may be the same or different, each represents a straight chain or branched alkyl or alkenyl group and the sum of the carbon atoms of R.sup.3, R.sup.4 and R.sup.

Abstract: A magnetic recording medium is disclosed, which has a magnetic layer on a non-magnetic support, wherein at least a mixture of ester compounds shown by formula (I) obtained by the reaction of a straight chain or branched fatty acid having from 12 to 30 carbon atoms and branched alcohols having from 10 to 32 carbon atoms synthesized by oxo synthesis is retained in or on the magnetic layer: ##STR1## wherein R.sub.1 represents a straight chain or branched alkyl group having from 11 to 29 carbon atoms or a straight chain or branched alkenyl group having from 11 to 29 carbon atoms, and R.sub.2 represents a branched alkyl group having from 10 to 32 carbon atoms. The magnetic recording medium has an excellent running durability in wide ranges of temperature and humidity condition.

Abstract: A magnetic recording medium is disclosed, which comprises a non-magnetic support having provided thereon a magnetic layer mainly composed of a ferromagnetic powder and a binder resin comprising (i) a polymer having at least one polar group selected from --SO.sub.3 M.sup.1, --OSO.sub.3 M.sup.1, --COOM.sup.1, ##STR1## wherein M.sup.1 represents a hydrogen atom, Li, Na or NR.sub.4 (wherein R represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkanol group), and M.sup.2 represents a hydrogen atom, Li, Na, an alkyl group, or NR.sub.4 (wherein R has the same significance as defined above); or (ii) a compound having at least one polar group selected from --SO.sub.3 M.sup.3, --COOM.sup.3, and --PO.sub.3 (M.sup.3).sub.2 (wherein M.sup.

Abstract: By coating a solid fertilizer with a coating material comprising an aqueous emulsion of resin as the main component to form a resin film having a glass transition temperature of 60.degree. C. or higher; or by coating a solid fertilizer with a coating material comprising an aqueous emulsion of a thermoplastic resin and a melamine resin, and heating the coated fertilizer at 70.degree. C. or higher; a gradually-effective, coated fertilizer having a distinguished gradual releasability and strong resistance to caking, which have been so far regarded as difficult to be obtained in an aqueous emulsion system, can be prepared.