Abstract: A hard disk drive includes a magnetic disk used as a magnetic recording medium, and a magnetic head for applying magnetic fields to the disk to record data and for detecting magnetic fields from the disk to reproduce data. During recording and reproducing, the head is moved relative to the disk so as to define a track, which is a series of a number of recording bits, on the disk. At this time, the head is brought into contact with the disk, with a head contact width in the track width direction. The disk has a surface texture which presents a single peak amplitude value falling in a range of being equal to or more than 0.5 nm, and equal to or less than the recording bit length, when the surface texture is factorized into frequency compositions by means of Fourier transform. A wave length for providing the peak amplitude value falls in a range of being ten times the recording bit length or more, and equal to or less than the head contact width.

Abstract: A magnetic recording medium of this invention includes an underlayer formed on a substrate and made of a material containing vanadium as a main constituent, and a magnetic film formed on the underlayer and made of a CoPtO-based alloy. Another magnetic recording medium of this invention includes a first underlayer formed on a substrate and made of a crystal having a crystal structure for forming a body-centered cubic lattice, a second underlayer formed on the first underlayer and made of an amorphous material, and a magnetic film formed on the second underlayer and made of a CoPtO-based alloy. Further, the magnetic recording medium according to the present invention includes an underlayer formed on a substrate, a plurality of magnetic films laminated on the underlayer and interlayers provided respectively between the plurality of magnetic films, in which the underlayer and the interlayers are made of vanadium or an alloy mainly containing vanadium.

Abstract: A hard disk drive includes a magnetic disk used as a magnetic recording medium, and a magnetic head for applying magnetic fields to the disk to record data and for detecting magnetic fields from the disk to reproduce data. During recording and reproducing, the head is moved relative to the disk so as to define a track, which is a series of a number of recording bits, on the disk. At this time, the head is brought into contact with the disk, with a head contact width in the track width direction. The disk has a surface texture which presents a single peak amplitude value falling in a range of being equal to or more than 0.5 nm, and equal to or less than the recording bit length, when the surface texture is factorized into frequency compositions by means of Fourier transform. A wave length for providing the peak amplitude value falls in a range of being ten times the recording bit length or more, and equal to or less than the head contact width.

Abstract: A longitudinal recording medium and a magnetic recording apparatus containing the same, comprising a substrate and a longitudinal magnetization film formed on the substrate containing grains of a Co-based alloy, and exhibiting an oxygen concentration distribution having two peaks as follows: a peak of higher oxygen concentration pertaining to grain boundaries of the longitudinal magnetization film, and a peak of lower oxygen concentration pertaining to grain interiors of the longitudinal magnetization film.

Abstract: According to the present invention, there is provided a magnetic disk memory system.

Abstract: A thin film type longitudinal magnetic recording medium is manufactured by forming a magnetic layer of Co.sub.1-x-y Pt.sub.x Cr.sub.y, (0.15<x.ltoreq.0.35; 0<y.ltoreq.0.15), on a substrate. The magnetic layer is formed by sputtering under an inert gas atmosphere containing 0.1 to 15% by volume of at least one of N.sub.2 and O.sub.2.

Abstract: A perpendicular magnetic recording medium comprises a base having a main surface and form, and a magnetic layer formed on the main surface, and having a recording surface, formed with a number of fine projections, and a susceptible axis substantially perpendicular to the recording surface. The projections are distributed so that the difference between a height level corresponding to an area ratio of 1.0%, obtained when the projections are cut by an imaginary plane parallel to the recording surface, and another height level corresponding to an area ratio of 99.0%, obtained in a like manner, ranges from 40 to 600 .ANG.. A protective film of a substantially uniform thickness is formed on the recording surface of the magnetic layer.

Abstract: An electrostatic latent image transfer type copying apparatus which has a photoconductive member, a system for forming an electrostatic latent image on the photoconductive member, an image transfer system for conducting transfer material having an insulating dielectric layer coated over an electrically conductive layer into contact with the photoconductive member for transferring the latent image onto said transfer material, a transporter for the transfer material to transport it along a predetermined path to the image transfer system, a member such as a relatively sharp edge member like a cutter provided along the path and below which the insulating dielectric layer side of the transfer material passes, and an insulating member provided adjacent the sharp edge member for preventing the surface of transfer material from contacting the sharp edge member as the transfer material is transported, whereby the contact of the sharp edge member with the surface of transfer material which causes frictional charging on

Abstract: An electrophotographic copying apparatus which includes a rotatable photoreceptor member having a photoconductive surface for repeated formation of an electrostatic latent image of an original thereon. A casing is disposed around the photoreceptor member and included a corona charger for uniformly charging the surface. An exposure device is provided for exposing the charged surface to image light of the original through an optical assembly including an illuminating light source so as to form the electrostatic latent image of the original thereon. A system is provided for eliminating harmful gases generated by the corona charger disposed within the copying apparatus.

Abstract: Apparatus for improving the quality of images obtained in an electrostatic latent image transfer type copier according to which there are provided electrical circuits permitting escape or neutralization of charges which may be produced in copy paper during its transport through a photocopying machine and could cause smudging or elimination of required image portions in developed copy paper carrying the image of a document or similar material.In the disclosed embodiment, the electrical circuits maintain each of the rollers of pairs of copy sheet transporting rollers at an equal potential.

Abstract: In a transfer type electrophotographic copying apparatus which comprises a reciprocating platform for supporting an original to be copied, a rotatable photoreceptor drum of a small diameter, and processing devices of small size disposed around the photoreceptor drum for compact size of the copying apparatus, an improved transfer device and a transferred image disturbance prevention device are further included for efficient copying operations.

Abstract: A transfer type electrophotographic copying apparatus with a reciprocating platform to place an original to be copied thereon, which comprises a rotatable photoreceptor drum of a small diameter, and processing devices of small size disposed around the photoreceptor drum with minimum spaces necessary between the processing devices, so that the size and weight of the copying apparatus can be reduced to a large extent. The housing of the apparatus can be divided into an upper frame and a lower frame with the upper frame pivotally connected to the lower frame for easy access to the internal mechanisms in maintenance and replacing of the parts.

Abstract: An electrophotographic copying apparatus which includes a rotatable photoreceptor member having a photoconductive surface for repeated formation of an electrostatic latent image of an original thereon. A casing is disposed around the photoreceptor member and included a corona charger for uniformly charging the surface. An exposure device is provided for exposing the charged surface to image light of the original through an optical assembly including an illuminating light source so as to form the electrostatic latent image of the original thereon. A system is provided for eliminating harmful gases generated by the corona charger disposed within the copying apparatus.