摘要:
A magnetic recording medium comprises: a non-magnetic base film; and a magnetic recording layer comprising a binder resin and black magnetic acicular composite particles having an average particle diameter of 0.051 to 0.35 μm, comprising magnetic acicular cobalt-coated iron oxide particles or magnetic acicular metal particles containing iron as a main component, a coating formed on surface of the magnetic acicular particles, comprising at least one organosilicon compound selected from the group consisting of: (1) organosilane compounds obtainable from alkoxysilane compounds, and (2) polysiloxanes or modified polysiloxanes, and a carbon black coat formed on the coating layer comprising said organosilicon compound, in an amount of from more than 10 to 40 parts by weight based on 100 parts by weight of said magnetic acicular particles. Such a magnetic recording medium exhibits not only a smooth surface, a smaller light transmittance and a lower surface electrical resistivity value, but also a small friction coefficient and an excellent running durability.
摘要:
A magnetic recording medium comprises: a non-magnetic base film; and a magnetic recording layer comprising a binder resin and magnetic composite particles having an average particle diameter of 0.02 to 0.70 &mgr;m, comprising magnetic particles as core particles, a coating formed on surface of said magnetic particle, comprising at least one organosilicon compound selected from the group consisting of: (1) organosilane compounds obtainable from alkoxysilane compounds, and (2) polysiloxanes or modified polysiloxanes, and a phthalocyanine-based pigments coat formed on said coating layer comprising said organosilicon compound, in an amount of 1 to 100 parts by weight based on 100 parts by weight of said magnetic particles.
摘要:
The present invention provides particles for a non-magnetic undercoat layer of a magnetic recording medium, which comprises acicular hematite particles having an average major axial diameter of not more than 0.3 &mgr;m, a geometrical standard deviation in the major axial diameter of not more than 1.50 and a BET specific surface area of not less than 40 m2/g, and containing a total amount of sodium of not more than 50 ppm calculated as Na. The acicular hematite particles have an excellent dispersibility in a vehicle so that a non-magnetic undercoat layer containing the particles is excellent in surface smoothness and strength. A magnetic recording medium using the non-magnetic undercoat layer is excellent not only in electromagnetic performance, but in storage stability.
摘要:
The present invention provides particles for a non-magnetic undercoat layer of a magnetic recording medium, which comprises particular hematite particles having an average major axial diameter of not more than 0.3 &mgr;m, a geometrical standard deviation in the major axial diameter of not more than 1.50 and a BET specific surface area of not less than 40 m2/g, and containing a total amount of sodium of not more than 50 ppm calculated as Na. The particular hematite particles have an excellent dispersibility in a vehicle so that a non-magnetic undercoat layer containing the particles is excellent in surface smoothness and strength. A magnetic recording medium using the non-magnetic undercoat layer is excellent not only in electromagnetic performance, but in storage stability.
摘要:
A magnetic recording medium of the present invention comprises: a base film; a non-magnetic undercoat layer formed on said base film and comprising a binder resin and non-magnetic acicular particles containing iron as a main component, comprising iron and titanium of 0.05 to 50% by weight, calculated as Ti, based on the total weight of the particles, which is present within the particle; and a magnetic recording layer formed on said non-magnetic undercoat layer and comprising magnetic particles and a binder resin. Such a magnetic recording medium has a low light transmittance, an excellent smooth surface, a high mechanical strength and an excellent durability.
摘要:
The disclosure describes a non-magnetic undercoating layer for a magnetic recording medium, coated on the surface of a non-magnetic substrate comprising: non-magnetic particles selected from the group consisting of particles (1) and (2): (1) coated acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles which are produced by adhering not less than 0.01 to 20 wt % (calculated as Al, SiO.sub.2 or Al and SiO.sub.2, and based on acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material) of an oxide or a hydroxide containing Al, Si or both Al and Si to the surfaces of acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material, and have a molecular weight-dependent parameter .alpha. represented by the following formula of not less than 0.5: As=K.sub.1 .multidot.M.sup..alpha. wherein M represents the number-average molecular weight of a binder resin, As represents the saturation adsorption of said binder resin, and K.sub.1 represents a constant used for measuring As and dependent on the binder resin and a solvent, (2) BaO.multidot.4.5Fe.sub.2 O.sub.3 particles having an average particle diameter of not more than 0.1 .mu.m; and a binder resin.
摘要翻译:本发明描述了一种涂覆在非磁性基材表面上的用于磁记录介质的非磁性底涂层,包括:选自颗粒(1)和(2)的非磁性颗粒:(1)涂覆 通过粘附不小于0.01至20重量%(以Al,SiO 2或Al和SiO 2计算,并以针状或纺锤形α-Fe2O3颗粒为核心材料)制备的针状或纺锤状α-Fe2O3颗粒, 含有Al,Si或Al和Si的氧化物或氢氧化物作为核心材料的针状或纺锤形α-Fe2O3颗粒的表面,并且具有不低于下列公式的分子量依赖参数α 比0.5:As =K1xMα其中M表示粘合剂树脂的数均分子量,As表示所述粘合剂树脂的饱和吸附,K1表示用于测量As的常数,并且取决于粘合剂树脂和溶剂, ( 2)平均粒径不大于0.1μm的BaO x 4.5 Fe 2 O 3粒子; 和粘合剂树脂。
摘要:
A magnetic recording medium using black magnetic acicular composite particles produced by forming a single carbon black coat between the surface of magnetic acicular cobalt-coated iron oxide particle or magnetic acicular metal particle and a coating comprising at least one organosilicon compound, in an amount of from more than 10 to 40 parts by weight based on 100 parts by weight of the magnetic acicular particles, exhibits not only a smooth surface, a smaller light transmittance and a lower surface electrical resistivity value, but also a small friction coefficient and an excellent running durability.
摘要:
A black colorant for ink-jet printing ink, has an average particle diameter of 0.001 to 0.15 &mgr;m, and comprises: extender pigments as core particles; a gluing agent-coating layer formed on at least a part or the surface of said core particles; and a black pigment coat uniformly formed on at least a part of said gluing agent-coating layer. The black colorant for ink-jet printing ink exhibits not only a high blackness and an excellent tinting strength, but also excellent dispersibility and light resistance in spite of fine particles.
摘要:
A colorant for ink-jet printing ink of the present invention, has an average particle diameter of 0.001 to 0.15 &mgr;m, and comprises: extender pigments as core particles; a gluing agent coating layer formed on at least a part of surface of said core particle; and an organic pigment coat uniformly formed on at least a part of said gluing agent coating layer. The colorant for ink-jet printing ink exhibits not only a high tinting strength and a clear hue, but also excellent dispersibility and light resistance in spite of fine particles.
摘要:
Organic and inorganic composite pigments having an average particle diameter of 0.01 to 10.0 &mgr;m composed of a white inorganic particle, an organosilane compound obtained from alkoxysilanes, or polysiloxanes coating on the white inorganic particle, and an organic pigment coat formed on said coating. An ultraviolet light-absorbing agent is present in any portion from the surface of the white inorganic particle to surface of the organic pigment coat. These composite pigments have reduced amounts of organic pigments desorbed from their surface and exhibit excellent light resistance due to their ultraviolet absorbing property.