摘要:
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.
摘要:
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.
摘要:
A magnetic recording medium is disclosed comprising a non-magnetic support having provided thereon a plurality of magnetic layers containing a ferromagnetic powder dispersed in a binder, wherein the lower magnetic layer closest to the support contains as the binder at least one polyurethane resin having a glass transition temperature (Tg) of from -50.degree. C. to -10.degree. C., and the uppermost magnetic layer contains as the binder at least one polyurethane resin having a glass transition temperature of from more than 40.degree. C. to 100 .degree. C.The magnetic recording medium of the present invention exhibits excellent running durability as well as electromagnetic conversion characteristics.
摘要:
A magnetic recording medium comprising a non-magnetic support having thereon at least one magnetic layer is disclosed, comprising a dispersion of ferromagnetic particles in a binder; said at least one magnetic layer comprising:(a) a surface comprising abrasive agents having a Mohs' hardness of 6 or more in an average amount of 0.3 to 1.4 particles/.mu.m.sup.2, and(b) a cutting cross section containing abrasive agents having a Mohs' hardness of 6 or more in an average amount of at least 0.1 particle/.mu.m.sup.2 greater than said average amount of abrasive agents contained on said surface.
摘要:
A method for measuring the thickness of a multi-layer magnetic recording medium which provides a high accuracy and which can be used for continuous on-line monitoring of product thickness. First, first and second magnetic layers are simultaneously coated onto a running nonmagnetic support to form the recording medium. The first and second magnetic layers are made of materials having different responses to fluorescent X-rays. Then, the thickness of at least one of said first and second layers is measured by exposing the recording medium to fluorescent X-rays.
摘要:
A method for simultaneously forming a plurality of organic-solvent-based magnetic layers on a moving support for the manufacture of a magnetic recording medium or the like. The surface tension of a solvent used to form the uppermost of the layers is made lower than that of the other layers. The most preferred range of the surface tension of the solvent which forms the uppermost layer is in a range of 0.1 to 3 dynes.
摘要:
A method for manufacturing a magnetic recording medium comprising the steps of: (1) providing a lower layer comprising a ferromagnetic powder dispersed in a binder on a non-magnetic support and (2) providing an upper layer comprising a ferromagnetic powder dispersed in a binder on the lower layer, wherein a solvent used in a magnetic coating composition for the lower layer contains at least 30 wt % of an organic solvent having an evaporation rate index of less than 50; a solvent used in a magnetic coating composition for the upper layer contains from 0 to 40 wt % of an organic solvent having an evaporation rate index of less than 50; the content of an organic solvent having an evaporation rate index of less than 50 in the coating composition for the upper layer is smaller than that in the coating composition for the lower layer; the magnetic coating composition for the upper layer is coated while the lower layer is not dried; and when the lower and upper layers are dried until the total solvent content of the lower and upper layers is in the range of from 0.05 to 3 wt %, a calendering treatment is carried out.
摘要:
A semiconductor integrated circuit includes a logic circuit which has first and second transistors constituting an emitter coupled transistor pair and a third transistor which is used as a constant current source, a bias circuit which includes a fourth transistor having an emitter from which a first predetermined voltage is supplied to a base of the third transistor and an impedance having one end coupled to a first power source and another end coupled to a base of the fourth transistor to supply a second predetermined voltage thereto, and a clamping circuit. The clamping circuit is OFF and does not perform a clamping operation with respect to the base of the fourth transistor when the entire semiconductor integrated circuit needs to operate. When the entire semiconductor integrated circuit does not need to operate, the clamping circuit is ON to clamp the base potential of the fourth transistor so as to reduce the power consumption of the semiconductor integrate circuit.
摘要:
A magnetic recording medium such as an audio-tape or a video-tape comprising a flexible support and a magnetic recording layer provided on one surface of said support, which is characterized in that the total of the thickness of said magnetic recording layer (dM) and the thickness of said support (dB), namely dM plus dB, is not larger than 14 .mu.m; the ratio of the thickness of said magnetic recording layer (dM) to the thickness of said support (dB), namely dM/dB, is in the range of 0.6-1.0; and said magnetic recording medium has F-3 tensile strength in the range of 6.0-8.5 kg/mm.sup.2.
摘要:
A magnetic recording medium such as an audio-tape or a video-tape comprising a nonmagnetic support and a magnetic recording layer provided on said support, said magnetic recording layer comprising a ferromagnetic powder dispersed in a binder, which is characterized in that said magnetic recording layer comprises at least one modified silicon compound having molecular weight of less than 3,000 and at least one modified silicon compound having molecular weight of not less than 3,000.