摘要:
A rubber composition capable of giving a highly oil-resistant vulcanizate with an organic peroxide as the vulcanizing agent is proposed. The composition is a blend of an EPM or EPDM rubber and an acrylic rubber loaded with a reinforcing filler, of which the latter rubber is a copolymer having at least two vinylsilyl groups in a molecule as the pendant groups introduced by the copolymerization of one or more acrylic monomers with a vinylsilyl-containing organosilicon compound having an aliphatically unsaturated group copolymerizable with the acrylic monomers in a molecule, such as CH.sub.2 .dbd.CH--CO--O--CH.sub.2 CH.sub.2 CH.sub.2 --Si-- and CH.sub.2 .dbd.CH--C.sub.6 H.sub.4 --Si--. The covulcanizate has the high mechanical strengths of the EPM or EPDM rubber and the high oil resistance of the acrylic rubber in combination.
摘要:
A mounting of semiconductor laser chip on a heat sink or metal mount is improved so as to enable high accuracy of position and direction. A heat sink or metal mount, on which a semiconductor laser chip is mounted, comprises two parts, namely a main mount or larger portion and a sub-mount or smaller portion. The semiconductor laser chip is soldered by a solder layer on the sub-mount utilizing a microscope so as to assure an accurate position and an accurate direction with respect to the sub-mount. Then, the sub-mount is soldered on the main mount by a solder layer with an accurate relation both in position and direction by engaging a linear ridge as a first engaging means provided on the upper face of the main mount with a straight groove and a rear end face as a second engaging means, or by engaging a square recess as a first engaging means and the square bottom of the sub-mount as a second engaging means with each other. As a result of the above-mentioned structure, accurate position and direction of the semiconductor laser chip with respect to the mount is easily obtainable with a high yield.
摘要:
The invention provides a highly flame-retardant polyolefin-based rubber composition free from the problem of the formation of toxic or corrosive gases and a large volume of smoke by burning of conventional flame-retardant rubber compositions impregnated with a large amount of a halogen-containing flame retardant agent. The inventive rubber composition comprises (a) a synthetic rubber of polyolefin type, (b) an organopolysiloxane resin which is preferably formed of monofunctional siloxane units and tetrafunctional siloxane units in a molar ratio of 0.6/1.0 to 2.0/1.0, (c) red phosphorus and (d) aluminum hydroxide or magnesium hydroxide in a specified proportion.
摘要:
In a semiconductor laser comprising an active layer epitaxially formed on a semiconductor substrate and at least a current limiting layer which defines a current injection region of a stripe shape,the improvement is that said substrate has a terrace part on its principle face,said active layer has two parallel bending parts defining a stripe shape active region facing said current injection region in between andsaid stripe shape active region is disposed with a specified angle to said principle face.
摘要:
In a semiconductor laser which has epitaxial layers including an active layer on a semiconductor substrate, a buffer layer is formed neighboring the active layer, in order to prevent undesirable diffusion of a highly diffusing dopant (Zn) into the active layer from an adjacent layer such as the second clad layer. The buffer layer has the same conductivity as that of the adjacent layer, has a broader energy gap than the active layer, and the dopant of the buffer layer is less diffusing than that of the adjacent layer.
摘要:
A semiconductor laser is made by sequential liquid-phase epitaxial growths on an n-type GaAs substrate, thereby sequentially forminga first layer of n-type GaAlAs,a second layer of n-type or p-type GaAs as active region,a third layer of p-type GaAlAs,said first to third layers forming a doublehetero structure,a fourth layer of p.sup.+ -type GaAs, anda fifth layer of n-type GaAlAs,by chemically etching the fifth layer, to form a groove or narrow window therein so as to expose a part of said fourth layer at the bottom of the groove, andby providing a metal electrode embedded in said groove.In the laser of the abovementioned construction, the fifth layer, instead of the conventional oxide film, serves as an isolation layer. However, the fifth layer, being an epitaxially grown GaAlAs layer, has better thermal conductivity than an oxide film. Therefore, when a suitable heat-sink means or heat-radiation means is provided thereon, a laser of good heat radiation characteristics is obtainable, enabling production of higher power continuous wave laser.The etching for forming the groove is easily made by chemically etching the desired layer by utilizing the difference in etching speed for different layers of hetero structure.
摘要:
Novel silicon-containing derivatives of polybutadiene or copolymers of butadiene with other copolymerizable monomer or monomers in which organosilicon-containing groups are bonded to the carbon atoms in the main chain of the butadiene polymers through the carbon-silicon linkages. These derivatives of butadiene polymers are produced by the addition reaction of an organosilicon compound having one hydrogen atom directly bonded to the silicon atom in the molecule to the double bonds in the butadiene polymers. They have a good fluidity, a small temperature dependency of viscosity, an excellent thermal stability and a high anti-oxidation resistance, as well as a good compatibility with siliceous fillers which are added to give improved workability and transparency to the compositions. The compositions to which a crosslinking agent and a curing catalyst are added can be cured into a rubber-like elastomer having excellent properties suitable for applications in various fields.
摘要:
A laminated multilayer sheet structure composed of (A) an opaque flexible sheet layer and (B) a flexible layer laminated to the surface of layer (A) and composed of a transparent thermic ray reflecting layer (B.sub.1) bonded to a transparent synthetic resin layer (B.sub.2). The sheet structure may be applied to the surface of a floor, wall, ceiling, partition or piece of furniture for indoor heat insulation.
摘要:
A mesa region of a stripe geometry is formed by mesa-etching a surface of a GaAs crystal substrate, forming a crystal layer of higher resistivity than the abovementioned crystal substrate so as to fill the abovementioned mesa-etched recesses in a manner that the stripe shaped mesa region is buried in the higher resistivity regions making top faces of the mesa region and the higher resistivity regions flush with each other, then forming, on the abovementioned flush surface, several epitaxial growth regions of semiconductor crystal including a light emitting region, for instance, an active region for lasing, subsequently forming contact isolation region having an opening of the stripe geometry corresponding to and above said mesa region. The current flow in the active region is confined in a narrow stripe region.