A photoconductor is the heart of plain paper copiers, non-impact printers and so on. Fuji Electric first developed a Se/Te photoconductor and placed it on the market and next eveloped a Se/As photoconductor of high sensitivity and high durability to extend the market. In recent years, we have commercialized an organic photoconductor (OPC) remarkably improved in the properties to complete the lineup of the product models. This paper outlines the features and uses of our nine types in OPC and Se groups and their prospects.

Fuji Electric has developed an organic photoconductor Type 8B for use in electrophotographic page printers with the following characteristics: (1) Widely adjustable high sensitivity using advanced-function conductive organic materials, (2) Long life due to a wearproof resinous materials combined with advanced-function conductive organic materials, (3) Compatible with various type of electrophotographic printers resulted from the outstanding technique of process evaluation and organic materials arrangement, (4) High environmental reliability, (5) Consists of safe chemical substances only.

Organic photoconductors for plain paper copiers (PPCs) came on the market because of low cost and unitized peripheral processes and have grown rapidly. Especially in recent years, their sensitivity and durability have been improved greatly by a construction such that several layers have their own function and organic materials of a wide variety are used for each layer. As a result, photoconductors of this type have come to be applied to high-speed PPCs as well as low- and medium-speed PPCs. To meet these market needs, Fuji Electric has developed organic photoconductors suitable for various speed PPCs.

There are two kinds of developing processes for xerography: the dry toner developing process and the liquid toner developing process. The latter is characterized by high resolution, superior reproducibility of gradation and easy fixation of images, and is suitable to a master for offset printing and a color proof for color separation films. The process will be applied in various fields that requires high-quality images such as digital plain paper copiers (PPCs)/printers and full color PPCs/printers.
Fuji Electric has developed an organic photoconductor for the liquid toner developing process first in the world.

With the progress of plain paper copiers (PPCs), Fuji Electric has made technical development to increase the sensitivity and reliability of selenium photoconductors. As a result, our photo-conductors can cover a wide range from low to high copy speed.
Selenium photoconductors are expected to come into wide use for high-speed PPCs with a copy speed of 70 copies/min or more. This paper describes technical point to enhance the performance of Se/As photoconductors suitable for the electrophotographic process in high-speed PPCs.

Fuji Electric has developed a multilayered selenium photoconductor type 4D based on Se/As and Se/Te which is suitable for non-impact laser diode or light-emitting diode printers.
This photoconductor consisting of a carrier transport layer (Se), a carrier-generating layer (Se/Te) and an overcoating layer (Se/As) shows high sensitivity in the infrared region (for example, half decay is 0.5μJ/cm² 780nm) and high durability of more than 102 k prints.

It is anticipated a high level of information interactive civilization will be realized in the 21 century. Among its essential elements is there a coordination of mankind's progress and computer's as well. Important factors are development of high speed central processing unit and realization of high speed and high capacity memory. Along this direction, hard disk drive as the most feasible device for the computer of next generation has been playing an important roll in various situations. Fuji Electric is a manufacturer of magnetic media which is an essential component of the hard disk drive. It is not only a leading company in the market today but is also engaged in various research and development fields to achieve higher levels tomorrow. This paper intends to introduce its present status as well as future directions.

As magnetic disks were intended for small size, thinness, and high density, the improvement of substrate quality has become necessary. A very small amount of zinc and copper are added to aluminum alloy substrates to make nickel-phosphorus plating easier. Machining causes substrate deformation in the succeeding process; therefore, a heating process is inserted before the grinding process to release residual stress. To get rid of substrate deformation in the polishing process, the machine and machining conditions have been improved. To make thinner substrates, materials, other than aluminum are under study.

The primaly purpose of texture process is to achieve high CSS durability and to take advantage of preffered orientation of magnetic characteristics along the direction processed. Our texture is a tape texture which requires technical experience as well as expertise since its performance is subject to various control-factors. An advantage of tape texture is its wide controllable range compared with the others.
A technology of precision profile measurement is essential to understand what level of practical performance, such as friction and head flyability, the surface textured exhibits. We take measurements, control process and do analyses with STM/AFM in addition to stylus type profilometer.

This paper outlines Fuji Electric's development in sputtering technique. (1) Magnetic materials CoNiCr, CoCrTa and CoCrPt were successively developed to meet high coercivity, and low noise by adding other elements and Lamination were achieved. (2) The protective carbon film obtained by adding methane to sputtering gas was optimized with quality controlled. (3) Target utilization was improved by optimizing cathode magnet arrangement and target shape with magnetic field calculation.

This paper outline Fuji Electric's lubricating technique for rigid magnetic disks. (1) Perfluoropolyether with a polar functional end group is widely used for carbon overcoated magnetic disks. A problem in quality was that some lots of products easily caused head stiction. We clarified that the lot variation was caused by the nonreacted and group and the low molecular component of the lubricant. (2) We developed a purification technique to remove such components using GPC liquid chromatography. (3) The purified lubricant is well suited for A12 O3･TiO hard sliders and shows good solubility in a substitute solvent for chlorofluorocarbons.

In the development of magnetic disk storages, testing technique to evaluate the result is an important item. Fuji Electric has developed various testing techniques since the start of media development. As a result, testing equipment for mass production that is necessary for quality assurance of products has been developed.
Future market demand for higher storage density will require the higher performance of media. To cope with the situation, a development of high level testing will be an essential subject in the development of these media.

This paper is a review of recent progress in the precise processing and defect level of magnetic disks with increasing recording density used for personal computer drives being downsized every year.
Fuji Electric started to produce magnetic disks with a diameter of 1.89 inches and a substrate thickness of 0.635 mm, of which semi-mass production has been started early this year. Furthermore, thinner AI substrates of 0.381 mm in thickness have been manufactured on an experimental basis and new materials for substrates such as glasses, Ti hard metal and ceramics are under investigation.

With advances in the compactness and capacity of hard disk drives, disks and heads have been demanded to have higher recording density. Then disks need to have higher coercivity and lower noise characteristics.
On the basis of the analyses of disks that have been changed to meet higher recording density, this paper reviews Fuji Electric's achievements for high coercivity and low noise. Also some potential structures for high-performance disks are examined from actual parametric and noise tests.

Aiming to develop disk storages of low flying height and high CSS durability, Fuji Electric is proceeding with various processes such as texturing, cleaning, sputtering, and lubrication. Particularly texturing and protective-layer forming are examined focusing on a slurry texturing method and a diamond-like-carbon protective layer respectively. Though the detailed mechanism of these techniques has to be clarified by later analysis in some respects, it is considered the present level can quarantee a flying height of 0.06 μm or less and CSS durability of 40k cycle or more.