Abstract: A slide electricity structure according to the present invention uses grease for electrical contacts wherein contact resistance does not gradually increase even when exposed to sliding and lifetime is long, and has a silver-plated spring contact that contacts or separates by way of sliding and grease for electrical contacts that has been applied to the spring contact and contains perfluoropolyether oil having an average molecular weight between 2600 and 12500 as a base oil and PTFE having a primary particle diameter of 1 ?m or less as a thickener.

Abstract: A grease composition, which comprises a mixture of mutually incompatible thickener-containing non-fluorine-based base oil and thickener-containing fluorine-based base oil, the base oils being in a morphological structure, where one of the base oils is homogeneously dispersed in a particulate state in the other base oil, can be produced by kneading the mixture through a three-roll mill at least twice. By forming a morphological structure, one of the mutually incompatible non-fluorine-based base oil and fluorine-based base oil is homogeneously dispersed in a particulate state in the other base oil, that is, by forming a microscopically dispersed state, the following effects can be obtained: (1) less oil separation (smaller degree of oil separation) at elevated temperatures, (2) distinguished shearing stability, (3) low and stable friction coefficient, and (4) less abrasion.

Abstract: A slide electricity structure according to the present invention uses grease for electrical contacts wherein contact resistance does not gradually increase even when exposed to sliding and lifetime is long, and has a silver-plated spring contact that contacts or separates by way of sliding and grease for electrical contacts that has been applied to the spring contact and contains perfluoropolyether oil having an average molecular weight between 2600 and 12500 as a base oil and PTFE having a primary particle diameter of 1 ?m or less as a thickener.

Abstract: A grease composition, which comprises a mixture of mutually incompatible thickener-containing non-fluorine-based base oil and thickener-containing fluorine-based base oil, the base oils being in a morphological structure, where one of the base oils is homogeneously dispersed in a particulate state in the other base oil, can be produced by kneading the mixture through a three-roll mill at least twice. By forming a morphological structure, one of the mutually incompatible non-fluorine-based base oil and fluorine-based base oil is homogeneously dispersed in a particulate state in the other base oil, that is, by forming a microscopically dispersed state, the following effects can be obtained (1) less oil separation (smaller degree of oil separation) at elevated temperatures, (2) distinguished shearing stability, (3) low and stable friction coefficient, and (4) less abrasion.

Abstract: In a vapor phase growth apparatus for performing a vapor phase growth of a silicon epitaxial layer on a main surface of a silicon single crystal substrate while heating the silicon single crystal substrate placed on a pocket formed on a susceptor, from both sides, the pocket has an outer peripheral side part which supports a rear surface of the silicon single crystal substrate and an inner peripheral side part which is kept in a state of being more recessed than the outer peripheral side part in the inside of the outer peripheral side part, and the susceptor has a warped inverted U-shaped longitudinal sectional shape.

Abstract: A quartz jig of this invention is such as being provided inside a semiconductor manufacturing apparatus allowing therein growth of an epitaxial layer on a main surface of a semiconductor wafer, capable of supporting a soaking jig which keeps, during epitaxial growth, uniform temperature of a susceptor allowing thereon placement of the semiconductor wafer, and has the top surface thereof aligned almost at the same level of height with the top surface of the susceptor, and is characterized as being composed of transparent quartz at least in a portion thereof brought into contact with the soaking jig. This configuration successfully provides a quartz jig supporting the soaking jig in the semiconductor manufacturing apparatus while suppressing generation of particles, and a semiconductor manufacturing apparatus provided with this sort of quartz jig.

Abstract: A magnetic fluid seal device that increases a permissible value of eccentricity for two members to improve sealability and decreases a variation of quality by injecting a magnetic fluid before assembling of parts, that saves structural members to achieve thinning, and that is easy to produce. An annular magnet 3 is buoyantly supported by the magnetic fluid 4 and 5 retained, and the space between a housing 1 and a shaft 2 is sealed by the annular magnet 3 and magnetic fluid 4 and 5.

Abstract: In a vapor phase growth apparatus for performing a vapor phase growth of a silicon epitaxial layer on a main surface of a silicon single crystal substrate while heating the silicon single crystal substrate placed on a pocket formed on a susceptor, from both sides, the pocket has an outer peripheral side part which supports a rear surface of the silicon single crystal substrate and an inner peripheral side part which is kept in a state of being more recessed than the outer peripheral side part in the inside of the outer peripheral side part, and the susceptor has a warped inverted U-shaped longitudinal sectional shape.

Abstract: A magnetic fluid seal device that increases a permissible value of eccentricity for two members to improve sealability and decreases a variation of quality by injecting a magnetic fluid before assembling of parts, that saves structural members to achieve thinning, and that is easy to produce. An annular magnet 3 is buoyantly supported by the magnetic fluid 4 and 5 retained, and the space between a housing 1 and a shaft 2 is sealed by the annular magnet 3 and magnetic fluid 4 and 5.

Abstract: There is provided a light shielding apparatus with a light shielding seal 1 that reduces a sliding resistance and, at the same time, improves light shielding property and realizes saving of a space. There is provided a light shielding structure that is provided between a plurality of members 13 and 14, which are arranged to be able to move relatively to each other spaced a predetermined distance apart, and is capable of preventing light from entering from a gap to be formed between these plurality of members 13 and 14, having magnetic force generating means 2 and 3 that are disposed in any one of the above-mentioned plurality of members 13 and 14 and magnetic fluid 4 which is magnetically held by the magnetic force generating means 2 and 3 and contacts the other member and shielding a gap, which is formed between the above-mentioned plurality of members 13 and 14, by the above-mentioned magnetic fluid 4.

Abstract: A fluorine-based magnetic fluid, which comprises (A) fine magnetic particles as dispersed in (D) a perfluoropolyether base oil represented by the following general formula:F?CF(CF.sub.3)CF.sub.2 O!mRfwhere Rf is a perfluoroalkyl group by means of general formulae:(B.sub.1){F?CF(CF.sub.3)CF.sub.2 O!nCF(CF.sub.2) (Y)v(R)wO}tPO(OM)u,(B.sub.2)F?CF(CF.sub.3)CF.sub.2 O!nCF(CF.sub.3)YRSO.sub.2 Mor(B.sub.3)F?CF(CF.sub.3)CF.sub.2 O!nCF(CF.sub.3)X(RO)sCH.sub.2 COOMwhere R is a divalent organic group; Y is a COO group or CONH group; X is a COO group or CH.sub.2 O group; and M is a hydrogen group, an alkali metal, an alkaline earth metal or an ammonium group and perfluoroether carboxylic acid amide compounds represented by the following general formulae:(C.sub.1)F?CF(CF.sub.3)CF.sub.2 O!pCF(CF.sub.3)CONH(CH.sub.2)qNH.sub.2,(C.sub.2)F?CF(CF.sub.3)CF.sub.2 O!pCF(CF.sub.3)CONH(CH.sub.2 CH.sub.2 NH)rHor(C.sub.3)F?CF(CF.sub.3)CF.sub.2 O!pCF(CF.sub.3)CONH(CH.sub.2 CH.sub.2 NH)rCOCF(CF.sub.3)?OCF.sub.2 CF(CF.sub.

Abstract: A fluorine-based magnetic fluid, which comprises (A) fine magnetic particles dispersed in (D) a perfluoropolyether base oil represented by the following general formula:F(CF(CF.sub.3)CF.sub.2 O).sub.m Rfwhere Rf is a perfluoroalkyl group, by means of (B) a perfluoroether carboxylic acid or salt thereof represented by the following general formula:F(CF(CF.sub.3)CF.sub.2 O).sub.n CF(CF.sub.3)COOMwhere M is a hydrogen atom, an alkali metal or an ammonium group, and (C) a perfluoroether compound represented by the following general formula:F(CF(CF.sub.3)CF.sub.2 O).sub.p CF(CF.sub.3)X(RO).sub.q CH.sub.2 COOM',F(CF(CF.sub.3)CF.sub.2 O).sub.p CF(CF.sub.3)(Y).sub.r R'OSO.sub.3 M' or(F(CF(CF.sub.3)CF.sub.2 O).sub.p CF(CF.sub.3)(Y).sub.v (R).sub.w O).sub.t PO(OM').sub.u.Fluorine-based magnetic fluid has a high affinity of the fine magnetic particles toward the perfluoropolyether base oil and is effectively used as a sealing material for vacuum apparatus.

Abstract: A fluorine-based magnetic fluid, which comprises (A) fine magnetic particles as dispersed in (D) a perfluoropolyether base oil represented by the following general formula:F?CF(CF.sub.3)CF.sub.2 O!mRfwhere Rf is a perfluoroalkyl group, by means of (B) a salt of perfluoroether carboxylic acid represented by the following general formula:F?CF(CF.sub.3)CF.sub.2 O!nCF(CF.sub.3)COOMwhere M is an alkali metal or an ammonium group, and (C) amide compounds of perfluoroether carboxylic acid represented by the following general formula:F?CF(CF.sub.3)CF.sub.2 O!pCF(CF.sub.3)CONH(CH.sub.2)qNH.sub.2,F?CF(CF.sub.3)CF.sub.2 O!pCF(CF.sub.3)CONH(CH.sub.2 CH.sub.2 NH)rH orF?CF(CF.sub.3)CF.sub.2 O!pCF(CF.sub.3)CONH(CH.sub.2 CH.sub.2 NH)rCOCF(CF.sub.3)?OCF.sub.2 CF(CF.sub.3)!pFhas a high affinity of the fine magnetic particles toward the perfluoropolyether base oil and is effectively used as a sealing material for vacuum apparatus.

Abstract: A magnetic fluid is produced by adding a solution of N-polyalkylenepolyamine-substituted alkenylsuccinimide in a hydrocarbon solvent to an aqueous suspension of fine particles of ferrites, thereby adsorbing the N-polyalkylenepolyamine-substituted alkenylsuccinimide onto the fine particles of ferrites, distilling off water and the hydrocarbon solvent therefrom, and dispersing the fine particles of N-polyalkylenepolyamine-substituted alkenylsuccinimide-adsorbed magnetites as residues into a base oil of low vapor pressure having a vapor pressure of not more than 0.1 mmHg at 25.degree. C.

Abstract: A magnetic fluid containing fine particles of ferrite stably dispersed in a carrier liquid is prepared by adding carrier liquid and a dispersing agent selected from N-polyalkylenepolyamine-substituted alkenylsuccinimide, an oxyalkylene-substituted phosphoric acid ester and a nonionic surfactant, and, if required, hydrocarbon solvent having a low boiling point to particles of ferrite which is coated with water-soluble surfactant and subjecting the resulting mixture to a dispersion treatment and, if required, removal of the hydrocarbon solvent.

Abstract: A magnetic fluid containing fine particles of ferrite stably dispersed in a low vapor pressure base oil is prepared by adding N-polyalkylenepolyamine-substituted alkenylsuccinimide (and a low vapor pressure base oil) to a suspension of fine particles of surfactant-adsorbed ferrite dispersed in a low boiling point hydrocarbon solvent, heating the resulting mixture, separating the hydrocarbon solvent therefrom, adding a low vapor pressure base oil and a specific dispersing agent to the fine particles of N-polyalkylenepolyamine-substituted alkenylsuccinimide-coated ferrite as the residues and subjecting the resulting mixture to a dispersion treatment.

Abstract: A sheltering apparatus for use in the long wall face of mine wherein a plurality of plates are arranged in overlapping manner between a self-advancing support and an adjacent plate, and hung from wires whose ends are fixed to the supports through springs, and an air curtain is fixed at the front open portion of the support, whereby floating dust and falling dusty materials can be repelled from entering the inner space of the supports.