Abstract: An optical disc used with an optical head with a focus depth of about 2 micron meter minimizes defects and deterioration in the optical disc at the time of manufacture, during operation and storage thereof as well. The optical disc includes a pair of transparent substrates each provided with at least one layer enabling recording of information, with the pair being bonded and laminated together has an instantaneous axial acceleration<2G.

Abstract: An optical disc used with an optical head with a focus depth of about 2 micron meter minimizes defects and deterioration in the optical disc at the time of manufacture, during operation and storage thereof as well. The optical disc includes a pair of transparent substrates each provided with at least one layer enabling recording of information, with the pair being bonded and laminated together has an instantaneous axial acceleration<2 G.

Abstract: The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration<2 G measured at room temperatures, a skew angle<5 mrad measured at room temperatures, and a skew angle<5 mrad measured after being left for one hour as heated to 80° C. (otherwise, a shear mass<20 &mgr;m measured after being left for one hour as heated to 80° C.

Abstract: A small-sized heat resisting high voltage transformer and an ignition transformer using the high voltage transformer are provided and utilize both a heat resistant casting resin and a bobbin, which contain an inorganic filler. The high voltage transformer is capable of producing an output voltage of 10-35 kV and comprises a primary coil, a secondary coil, and a magnetic core, wherein a casting resin is injected into the coil part and subsequently cured. The casting resin and bobbin material used for making the coils have heat distortion temperature of at least 130° C., and contain an inorganic filler. The surface of the bobbin may be pretreated. Thereby, adhesion between a bobbin and a casting resin is enhanced to ensure operating properly under the sever heat cycle condition and provide a small-sized heat resistant high voltage transformer.

Abstract: The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration<2 G measured at room temperatures, a skew angle<5 mrad measured at room temperatures, and a skew angle <5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass<20 .mu.m measured after being left for one hour as heated to 80.degree. C.

Abstract: The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through spcifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration<2 G measured at room temperatures, a skew angle<5 mrad measured at room temperatures, and a skew angle<5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass<20 .mu.m measured after being left for one hour as heated to 80.degree. C.

Abstract: An optical disk producing apparatus produces an optical disk by bonding a pair of replica disks together. The replica disks are disposed in a sealed space to oppose to each other with a predetermined gap therebetween. The sealed space is defined by a peripheral wall and opposite ends. The peripheral wall is divided into two portions which are slidingly movable relative to each other. When the sealed space is evacuated, the two portions are moved to apply an atmospheric pressure to the replica disks, so that the replica disks are bonded together into an optical disk.

Abstract: The object of the present invention is to provide an optical disc, a method of manufacturing thereof and an optical reproduction apparatus including the same wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration <2G measured at room temperatures, a skew angle <5 mrad measured at room temperatures, and a skew angle <5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass <20 .mu.m measured after being left for one hour as heated to 80.degree.

Abstract: An optical disk producing apparatus produces an optical disk by bonding a pair of replica disks together. The replica disks are disposed in a sealed space to oppose to each other with a predetermined gap therebetween. The sealed space is defined by a peripheral wall and opposite ends. The peripheral wall is divided into two portions which are slidingly movable relative to each other. When the sealed space is evacuated, the two portions are moved to apply an atmospheric pressure to the replica disks, so that the replica disks are bonded together into an optical disk.

Abstract: The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration <2 G measured at room temperatures, a skew angle <5 mrad measured at room temperatures, and a skew angle <5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass <20 .mu.m measured after being left for one hour as heated to 80.degree. C.

Abstract: This invention is related to an optical data recording medium of a high reliability and a large capacity, preventing moisture absorption and swelling of a resin layer formed on one side of a transparent substrate, and related to a method for manufacturing thereof wherever the optical data recording medium comprises at least a transparent substrate, a transferred layer of a preformat pattern formed on the transparent substrate and a thin film layer formed on the transferred layer wherein at least the surface of the transferred layer in contact with the transparent substrate is made of a resin layer composed of an ultraviolet ray curable resin resulting in an optical data recording medium having a reduced absorbing moisture of the transferred layer thereof and wherever the ratio of swelling (.DELTA.d/d) is restricted to 0.1% or less.

Abstract: The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration <2G measured at room temperatures, a skew angle <5 mrad measured at room temperatures, and a skew angle <5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass <20 .mu.m measured after being left for one hour as heated to 80.degree. C.

Abstract: Disclosed are a novel azide compound represented, for example, by the formula, ##STR1## wherein R.sub.f represents a fluoroalkyl or fluoroalkylpolyether group, ##STR2## wherein R represents a divalent organic group having an ester bond, and R.sub.f ' represents a fluoroalkylpolyether group, and a novel diacylhydrazine compound having a fluoroalkylpolyether group in the side chain and lubricants containing them. When this lubricant is coated onto the carbonaceous protective film of magnetic recording media and reacted by the action of light or heat, it strongly bonds or adheres to the protective film. Thus, the durability of the lubricant improves, as a result of which a high-density magnetic recording medium having a high reliability and long life can be obtained.

Abstract: This invention relates to insulated wires having good heat resistance and solderability. In particular, wires coated with a polyimide resin or an imide-modified polyurethane resin are provided. They can each be produced by coating a conductor with an insulating coating composition which contains a polyamic acid represented by the following formula: ##STR1## wherein R.sup.1 means a particular tetravalent organic group, R.sup.2 denotes a specific divalent organic group, X is an alkylene or alkylenephenylene group, and n stands for a positive integer.

Abstract: The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration <2G measured at room temperatures, a skew angle <5 mrad measured at room temperatures, and a skew angle <5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass <20 .mu.m measured after being left for one hour as heated to 80.degree. C.

Abstract: This invention is related to an optical data recording medium of a high reliability and a large capacity, preventing moisture absorption and swelling of a resin layer formed on one side of a transparent substrate, and related to a method for manufacturing thereof whatever the optical data recording medium comprises at least a transparent substrate, a transferred layer of a preformat pattern formed on the transparent substrate and a thin film layer formed on the transferred layer wherein at least the surface of the transferred layer in contact with the transparent substrate is made of a resin layer composed of an ultraviolet ray curable resin resulting in an optical data recording medium having a reduced absorbing moisture of the transferred layer thereof and whatever the ratio of swelling (.DELTA.d/d) is restricted to 0.1% or less.

Abstract: A method for making a cathode ray tube involves the step of positioning a non-reflective transparent plate in front of a face plate of a tube body with a given space therebetween; a step of filling the space with a resin composition and a step of heating the resin composition filled in the space to harden the composition to bond the tube body and the non-reflective transparent plate to each other. The resin composition is an unsaturated polyester resin composition which comprises an unsaturated polyester having a molecular weight per one unsaturated group of 1000 to 8000 and (1) a polymerizable monomer, a low-temperature hardener and a high-temperature hardener or (2) styrene and/or a derivative thereof and an unsaturated compound having a refractive index of 1.5 or less. This composition can be molded in a short time and forms no strain on hardening and serves as an adhesive for production of the cathode ray tube.

Abstract: This invention relates to a replica plate having a transparent plastic substrate and a photo-cured resin, and a projection type television using the replica plate. An adhesive layer comprising an acrylic or methacrylic compound is provided between a transparent plastic plate and a replica-forming photo-curable resin, whereby it is possible to enhance the adhesion between the surface of the transparent plastic plate and the photo-cured resin, and to produce a replica plate having excellent optical characteristics, good replicating properties and high reliability. The adhesive layer can be provided (1) by coating a layer containing the acrylic or methacrylic compound on the plastic plate, the compound infiltrating into the plate, or (2) by incorporating the acrylic or methacrylic compound into the photo-curable resin, the compound infiltrating therefrom into the plate; in this latter technique, the plate coated with the resin should be heated.

Abstract: A polymer excellent in transparency, mechanical properties, moisture resistance suitable for optical use is obtained by copolymerizing a (meth)acrylate compound (I) and a (meth)acrylate compound (II).

Abstract: A method for producing an optical disk base to store, record, and retrieve sounds, images, and information. An improved method for producing an optical disk base includes the steps of injecting a photo-curable resin into a cavity, curing the photo-curable resin by irradiation with light, and demolding, where the photo-curable resin is injected from an injection nozzle having an outside diameter which is substantially equal to the diameter of the center hole of the optical disk base and also having a horn-shaped opening at the forward end. The injection nozzle is arranged at the center of the optical disk base. The forward end of the nozzle is closed after injection and the photo-curable resin is irradiated with light, with the injection nozzle projected into the cavity. A liquid resin is injected in the form of uniform flow without entrapped bubbles, so that the anamolous molecular orientation is avoided and the contamination with insufficiently cured or uncured resin is also avoided.