摘要:
The present invention provides a magnetic recording medium comprising a magnetic layer with excellent surface smoothness, which comprises a thin film magnetic layer of thickness in a range from 0.03 to 0.30 μm that is ideal for short wavelength recording, and displays superior electromagnetic conversion characteristics. The magnetic recording medium comprises a magnetic layer containing at least a ferromagnetic powder and a binder resin on one surface of a non-magnetic support, wherein the thickness of the magnetic layer is within a range from 0.03 to 0.30 μm, and the number of concavities with a depth of 30 nm or greater in the surface of the magnetic layer is 5 per 1 cm2 of surface area or less. Preferably, the value of the average depth Rv6 of the surface of the magnetic layer, as measured by a contact type surface roughness meter, is 12 nm or less.
摘要:
The present invention provides a magnetic recording medium comprising a magnetic layer with excellent surface smoothness, which comprises a thin film magnetic layer of thickness in a range from 0.03 to 0.30 μm that is ideal for short wavelength recording, and displays superior electromagnetic conversion characteristics. The magnetic recording medium comprises a magnetic layer containing at least a ferromagnetic powder and a binder resin on one surface of a non-magnetic support, wherein the thickness of the magnetic layer is within a range from 0.03 to 0.30 μm, and the number of concavities with a depth of 30 nm or greater in the surface of the magnetic layer is 5 per 1 cm2 of surface area or less. Preferably, the value of the average depth Rv6 of the surface of the magnetic layer, as measured by a contact type surface roughness meter, is 12 nm or less.
摘要:
The present invention provides a magnetic recording medium comprising a magnetic layer with excellent surface smoothness, which comprises a thin film magnetic layer of thickness in a range from 0.03 to 0.30 μm that is ideal for short wavelength recording, and displays superior electromagnetic conversion characteristics. The magnetic recording medium comprises a magnetic layer containing at least a ferromagnetic powder and a binder resin on one surface of a non-magnetic support, wherein the thickness of the magnetic layer is within a range from 0.03 to 0.30 μm, and the number of concavities with a depth of 30 nm or greater in the surface of the magnetic layer is 5 per 1 cm2 of surface area or less. Preferably, the value of the average depth Rv6 of the surface of the magnetic layer, as measured by a contact type surface roughness meter, is 12 nm or less.
摘要:
The present invention provides a magnetic recording medium comprising a thin film magnetic layer of thickness in a range from 0.03 to 0.30 μm, and having excellent surface smoothness and superior electromagnetic conversion characteristics. The magnetic recording medium comprises a lower non-magnetic layer containing at least a non-magnetic powder and a binder resin on one surface of a non-magnetic support, an upper magnetic layer containing at least a ferromagnetic powder and a binder resin on the lower non-magnetic layer, and a back coat layer on the other surface of the non-magnetic support, wherein the thickness of the upper magnetic layer is within the range from 0.03 to 0.30 μm, the AFM surface roughness Ra of the upper magnetic layer is 6 nm or less, and the number of concavities with a depth of 30 nm or greater in the surface of the upper magnetic layer is 5 per 1 cm2 of surface area or less.
摘要:
A magnetic recording medium is prepared by coating a dispersion of non-magnetic powder and ferromagnetic powder in a binder and a dispersion of ferromagnetic powder in a binder to a non-magnetic substrate by a wet-on-wet coating technique to form subordinate and magnetic layers on the substrate, and subjecting the layers to magnetic field orientation. The subordinate layer has a Br of 80 to 400 gauss, and the magnetic layer has a thickness of 0.1 to 0.4 μm. The medium has surface smoothness and good electromagnetic characteristics and lends itself to recording and reproducing signals having a minimum wavelength of 0.2 to 0.7 μm.
摘要:
A magnetic recording medium has a non-magnetic layer and a magnetic layer formed in that order on one surface of a non-magnetic support and a back coat layer formed on the other surface of the non-magnetic support. The non-magnetic layer is formed so as to include at least one of α-iron oxide and α-iron hydroxide. The magnetic layer is formed so as to include a ferromagnetic alloy powder. The back coat layer is formed so as to include carbon black, and barium sulfate. At least one of the non-magnetic layer and the magnetic layer includes lubricant. The layers are formed so that the amount of SO42− eluted when the magnetic recording medium is immersed in water at 70° C. is in a range of 300 ppm to 600 ppm inclusive relative to the weight of the magnetic recording medium.
摘要:
A magnetic recording medium comprising a non-magnetic base having on at least one side a non-magnetic layer (undercoat) containing electron beam-curable resins which in turn is over-laid with a magnetic layer (topcoat) containing an iron (Fe) based magnetic powder, said magnetic layer having a glass transition temperature (Tg) of at least 65.degree. C. and said non-magnetic layer being an electron beam cured coating that is formed by coating the non-magnetic base with a non-magnetic coating mix containing electron beam curable resins, the yet to be cured coating having a glass transition temperature (Tg) of 30-53.degree. C. and said electron beam curable resins comprising an electron beam curable vinyl chloride based resin having a sulfur-containing polar group and an electron beam curable urethane resin having a phosphorus-containing polar group. Also disclosed is a process for producing the magnetic recording medium, which has good electromagnetic conversion characteristics in a high-frequency range and which can be manufactured at high production rate.
摘要:
A magnetic recording medium having an intermediate layer excellent in conductivity, surface properties and strength, and excellent in electromagnetic characteristics, physical properties, etc., which comprises a non-magnetic intermediate layer having a thickness of 0.5 .mu.m to 3.0 .mu.m formed on at least one surface of a non-magnetic support, and a magnetic layer formed on the intermediate layer, the magnetic layer being mainly composed of a ferromagnetic powder and a binder and having a thickness of 0.1 .mu.m to 0.5 .mu.m, in which said magnetic layer is formed on the intermediate layer at least in a dry state, and the intermediate layer comprises (A) an inorganic material having an average particle size of 10 nm to 50 nm and a Mohs' hardness of 7 or less, (B) an inorganic material having an average particle size of 100 nm to 500 nm and a Mohs' hardness of 9 or more, (C) carbon black, a lubricant and a binder.
摘要:
The present invention provides a high recording density magnetic recording medium with excellent surface smoothness, as well as excellent electromagnetic conversion characteristics and durability. A magnetic recording medium comprising a lower non-magnetic layer containing at least a non-magnetic powder and a binder resin on a non-magnetic support, and an upper magnetic layer with a thickness of 0.2 μm or less on said lower non-magnetic layer, wherein said lower non-magnetic layer contains an acicular powder of hydrated iron oxide as the non-magnetic powder, and said lower non-magnetic layer contains a fatty acid and a fatty acid amide. Preferably the acicular powder of hydrated iron oxide is goethite with an average long axial length of 0.15 μm or less.
摘要:
The average major-axis length (L) of a ferromagnetic alloy powder primarily contained together with a binder in a magnetic layer provided on at least one surface of a non-magnetic support is less than 0.10 μm, and the ferromagnetic alloy powder contains Co at a content of 15 to 28 at % relative to Fe, and furthermore, contains Y at a content of 22 μmol/m2 or more with respect to a specific surface area (Sc) calculated from the above-mentioned average major-axis length (L) and the crystallite diameter (d). A coating-type high-recording-density magnetic recording medium has excellent surface properties, an excellent electromagnetic transducing characteristic especially in short wavelength regions and high reliability.
摘要翻译:在非磁性载体的至少一个表面上设置的磁性层中主要与粘结剂一起含有的铁磁性合金粉末的平均长轴长度(L)小于0.10μm,铁磁性合金粉末含有Co 相对于Fe为15〜28原子%的含量,此外,相对于从上述平均长轴长度(L)算出的比表面积(Sc),含有Y为22μmol/ m 2以上的Y )和微晶直径(d)。 涂布型高记录密度磁记录介质具有优异的表面性能,特别是在短波长区域和高可靠性下具有优异的电磁感应特性。