Abstract: There is disclosed a storage apparatus which is of a system of utilizing a polarized state change by Kerr effect to read information from a storage medium and which easily and precisely performs adjustment to compensate for a phase deviation between both P, S polarized components attributed to an optical system. Phase plates 500, 510 are disposed between a fixed optical section 200 and a movable optical section 190 and the inclination angles of the phase plates are adjusted.

Abstract: A material for an insulating film which comprises a copolymer obtained by reacting a polyamide having a specific structure and a reactive oligomer as a component forming the film; a coating varnish for an insulating film which comprises this material and an organic solvent; an insulating film which comprises a layer of a resin comprising as a main structure a polybenzoxazole which is obtained by treating the above material or the above coating varnish by heating so that condensation reaction and crosslinking reaction take place and has fine pores; and a semiconductor device which comprises an insulating interlayer film for multi-layer wiring comprising the insulating film and/or a surface protective film comprising the insulating film. Excellent electrical, thermal and mechanical properties are exhibited and a low permittivity can be achieved.

Abstract: A precursor of a polybenzoxazole resin which comprises a crosslinking group in a molecule and has a specific structure, a polybenzoxazole resin obtained from the precursor by the condensation reaction and the crosslinking reaction, an insulating film comprising the polybenzoxazole resin and a semiconductor device comprising an insulating interlayer film in multi-layer wiring or a film for protecting surfaces which comprises the above insulating film. The precursor exhibits excellent processability due to excellent solubility in solvents and, after the ring closure, excellent heat stability in applications. The resin exhibits excellent electric, physical and mechanical properties and is advantageously used for insulating interlayer films of semiconductor devices and the like applications.

Abstract: The present invention provides a layer insulating film for multilayer interconnection of semiconductors which is excellent in resistance to heat, resistance to moisture absorption as well as in electric characteristic properties, and a process for producing the film. That is, a layer insulating film for multilayer interconnection of semiconductors which comprises a fluorine-containing polybenzoxazole resin having the structure represented by the formula (6) and obtained by a process which comprises subjecting to heat-dehydrating ring closure a fluorine-containing polyhydroxyamide resin obtained by reacting a dicarboxylic acid diester obtained from one kind of compound selected from the group of compounds represented by the formulas (2) and 2,2′-bis(tri-fluoromethyl)-4,4′-biphenyldicarboxylic acid, with 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, (in the formula (6), m is an integer of 10-500).

Abstract: A precursor of a polybenzoxazole resin which comprises a crosslinking group in a molecule and has a specific structure, a polybenzoxazole resin obtained from the precursor by the condensation reaction and the crosslinking reaction, an insulating film comprising the polybenzoxazole resin and a semiconductor device comprising an insulating interlayer film in multi-layer wiring or a film for protecting surfaces which comprises the above insulating film.

Abstract: A primary object of the invention is to provide a production technology for functional polyamic acid microfine particles and functional polyimide microfine particles by which the particle shape, size and size distribution can be freely controlled. The invention is concerned with a process for synthesizing polyamic acid particles having functional groups at least on the surface from a tetracarboxylic anhydride and a diamine compound characterized by its comprising (a) a first step which comprises providing a tetracarboxylic anhydride and a diamine compound at least one of which has functional groups and preparing a first solution containing the tetracarboxylic anhydride and a second solution containing the diamine compound and (b) a second step which comprises mixing the first and second solutions under ultrasonic agitation to thereby precipitate polyamic acid microfine particles from the mixed solution.

Abstract: An object of the invention is to provide thermosetting amic acid microfine particles, thermosetting imide microfine particles and crosslinked imide microfine particles of controlled particle shape and size distribution. The invention provides a production technology which comprises mixing a first solution containing a tetracarboxylic anhydride and a C═C bond-containing acid anhydride with a second solution containing a diamine compound, causing precipitation of thermosetting amic acid microfine particles from the resulting mixture, and further producing thermosetting imide microfine particles and crosslinked imide microfine particles from the thermosetting amic acid microfine particles.

Abstract: Provided is a compact inexpensive optical disk drive adaptable to high-density optical disks and having an improved stationary optical unit. The storage device has a first light path and a second light path defined therein. Along the first light path, laser light emanating from a laser light source is passed through a collimator lens and a beam splitter and routed to a movable optical system that is movable on an optical disk. Along the second light path, light reflected from the optical disk and returned from the movable optical system is split into a plurality of rays by the beam splitter, and one of the rays is routed to a sensor via a servo unit and a condenser. An angle at which the second light path meets the first light path is 90°+&agr;° where &agr; denotes a positive number.

Abstract: Heat resistant polybenzoxazole resins useful as layer insulation films and protective films for semiconductor, layer insulation films for multilayer circuits, cover coats for flexible copper-clad sheets, solder resist films, liquid crystal-aligned films and the like. These resins have excellent thermal, electrical, physical and mechanical characteristics. Polybenzoxazole precursors are provided, represented by the general formula (A), and are used to obtain polybenzoxazole resins, represented by the general formula (D). In the formulas (A) and (D), n denotes an integer from 2-1000, and X denotes a structure having a formula selected from structures indicated at (B). In the formulas at (B), Y denotes a structure having a formula selected from those indicated at (C), and the hydrogen atom(s) on the benzene ring in these structures are optionally substituted.

Abstract: A process for producing polyimide microfine particles which is amenable to free control of particle morphology and particle diameter distribution is provided. A polyamic acid and a polyimide, each in the form of microfine particles with good monodispersibility, are also provided. There is also provided a process for producing polyimide microfine particles from a tetracarboxylic anhydride and a diamine compound which comprises (a) a first step of preparing a first solution containing the tetracarboxylic anhydride and a second solution containing the diamine compound, (b) a second step of mixing the first and second solutions and causing a polyamic acid to precipitate in the form of microfine particles from the mixed solution under ultrasonic agitation, and (c) a third step of imidating the polyamic acid particles to provide the objective polyimide in the form of microfine particles.

Abstract: A phenolic resin molding material for molding at lower than normal pressures, comprising as resin components a combination of (A) a crystalline phenolic compound having two or more hydroxyphenyl groups and (B) a compound having two or more hydroxyl groups in the benzene ring, or (A), (B) and (C) a phenolic resin.

Abstract: A lamp is attached to the back end of a synthetic resin reflector through a synthetic resin lamp holder. A heat shielding member made of a metal such as stainless steel, aluminium or general steel plate is appropriately attached to the lamp holder to cover the circumferential face of said lamp holder in such a way that said circumferential face is not subjected directly to the light projected from a filament in the lamp.