Abstract: An anti-HTLV-I agent comprising as an effective component a streptovaricin C derivative represented by the general formula (I): ##STR1## wherein R.sup.1 represents an alkyl group having 3 to 7 carbon atoms. The streptovaricin C derivative has good HTLV-I killing activity, and this agent is useful for therapy of diseases caused by HTLV-I.

Abstract: An anti-AIDS virus agent comprising as an effective component a streptovaricin C derivative represented by the general formula (I): ##STR1## wherein R.sup.1 represents an alkyl group having 3 to 7 carbon atoms. The streptovaricin C derivative has good HIV-growth inhibiting activity, and this agent is useful for therapy of AIDS.

Abstract: Curable or vulcanizable fluorinated silicone compositions which comprise a uniform mixture of predetermined amounts of an organopolysiloxane of the following average unit formula ##STR1## in which R.sup.1 represents a monovalent hydrocarbon group having from 1 to 8 carbon atoms, and a and b are, respectively, a defined value; an organohydrogenpolysiloxane having at least three SiH groups in one molecule and consisting of the several siloxane units; and a catalytic amount of a platinum compound. If necessary, another type of polysiloxane may be added to the above composition in order to further improve physical properties. The composition is rapidly vulcanized to give a cured product having stable physical properties within a short time.

Abstract: A vinyl chloride copolymer is produced by copolymerizing vinyl chloride monomer or a monomer mixture comoposed of vinyl chloride monomer and copolymerizable monomer, with one or more than one kind of cross-linking agent selected from polyhydric alcohol diglycidyl ether diacrylate and dimethacrylate. The vinyl chloride copolymer has good moldability and can be made into moldings having good matte finish surface and also good permanent compression set resistance, creep resistance, heat resistance, and electrical properties.

Abstract: A process for preparing organopolysiloxane emulsion comprised of dispersed particles having an average particle size of 0.5.mu. or less, comprising emulsifying a liquid organopolysiloxane with use of an emulsifying agent by means of a composite emulsifying apparatus equipped with(A) a stirring means having a stirring blade capable of stirring contents of a container at a low speed over the whole of the container, and at least one stirring means selected from(B) a disc type stirring means capable of rotating at a high speed and having tooth-like projections on its peripheral edge, and(C) a stirring means having a stator and a turbine blade disposed in the inside of the stator and capable of rotating at a high speed. According to this process, an organopolysiloxane having a high viscosity up to 500,000 cP can be emulsified to prepare an emulsion of high stability.

Abstract: A self-adhering silicone composition comprising;(A) 100 parts by weight of an organopolysiloxane(B) 0.01 to 10 parts by weight of an organic peroxide represented by the formula (II): ##STR1## wherein R.sup.2 represents a hydrogen atom, an alkyl group or alkoxy group having 1 to 10 carbon atoms; R.sup.3 represents an alkyl group having 1 to 10 carbon atoms or a phenyl group; a is an integer of 1 to 3 and b is an integer of 0 to 2, provided that a+b=3; and c is an integer of 1 to 3 and d is an integer of 0 to 2, provided that 1.ltoreq.c+d.ltoreq.5.This composition can bring about strong and durable adhesion to substrates without use of any primers.

Abstract: An elastomer roll comprising a roll core, a first layer of a cured organopolysiloxane composition, and a second thin layer of a fluorine resin formed in this order. The organopolysiloxane composition is comprised of an organopolysiloxane, a finely divided silica filler, an organosilicon material having at least one hydrogen atom bonded to the silicon atom in one molecule, iron oxide, a fluorine resin, and an organic peroxide in defined amounts.

Abstract: Whereas the mechanism for the crosslink formation in the curable organopolysiloxane composition of the invention is the ultraviolet-induced addition reaction between alkenyl, e.g., vinyl, groups in a diorganopolysiloxane and mercaptoalkyl groups in another organopolysiloxane as in conventional compositions, the mercaptoalkyl-containing organopolysiloxane used in the invention is, differently from those in conventional compositions, an organopolysiloxane of a three-dimensionally branched molecular structure as composed of the siloxane units of the formulas R.sup.1.sub.3 SiO.sub.0.5, R.sup.1.sub.a (HSR.sup.2)SiO.sub.(3-a)/2 and SiO.sub.2, in which R.sup.1 is, for example, a methyl or phenyl group, R.sup.2 is, for example, --CH.sub.2 CH.sub.2 CH.sub.2 -- and a is zero, 1 or 2, in a specified proportion. In addition, the vinyl group-containing siloxane units in the vinyl-containing diorganopolysiloxane are localized in the molecular structure forming two blocks each bonded to one of the terminal silicon atoms.

Abstract: The copper-foiled laminated sheet of the invention is used to prepare a printed circuit sheet having see-throughness after patterning by etching of the copper foil. Different from conventional copper-foiled laminates using an electrolytic copper foil having a surface roughness of 10 or larger, the inventive laminate is prepared using a rolled copper foil having a surface roughness of 1.5 to 5 so that the surface of the adhesive layer, from which the copper foil has been removed by etching, has no undue roughness as a replica of the copper foil surface not to irregularly diffuse the light giving a parallel light-beam transmission of at least 50% and overall light transmission of at least 70% to ensure good see-through visibility.

Abstract: A fluorine-containing coating agent which can be used for forming a fluorocarbon resin coating film on a substrate comprises a polymer which has a fluorine-containing polymer as a main chain and an alkoxysilyl group in the side chain and which is obtained by the reaction of a hydroxyl group of a fluorine-containing polymer having the hydroxyl group in the side chain with an isocyanato group of an alkoxysilane having the isocyanato group. The fluorine-containing polymer having a hydroxyl group in the side chain is a copolymer of a fluoro-olefin and a hydroxyalkyl vinyl ether having a straight or branched alkyl group having 2 to 5 carbon atoms. The alkoxysilane having an isocyanato group is a compound represented by the following formula:OCN(CH.sub.2).sub.3 SiX.sub.n R.sub.(3-n) (I)whereinR is hydrogen or a monovalent hydrocarbon group haviang 1 to 10 carbon atoms,X is an alkoxyl group having 1 to 5 carbon atoms, andn is an integer of 1 to 3.

Abstract: Disclosed are a block-graft copolymer comprising a polymer block having a repeating unit represented by General Formula (I): ##STR1## wherein A is a side chain and represents an organopolisiloxane chain, a polyacrylate chain, a polymethacrylate chain, polydiene chain, etc.and a process for producing the same. This block-graft copolymer can have various performances such as oxygen enrichment performance, biocompatibility, depending on the kind of side chains.

Abstract: An organosilicon compound represented by General Formula (I): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 may be the same or different, and each represent a substituted or unsubstituted monovalent hydrocarbon group, x and y each represent an integer of 1 to 3, and n is an integer of 0 or more.This compound is useful as a starting material for ultraviolet curable silicone compositions and room temperature curable silicone compositions.

Abstract: The curable and foamable organopolysiloxane composition comprises three different organopolysiloxanes, of which (A) the first is an .alpha.,.omega.-divinyl dimethyl polysiloxane, (B) the second is an organopolysiloxane having, in a molecule, at least three silicon-bonded hydroxy groups and (C) the third is an organohydrogenpolysiloxane having, in a molecule, at least two silicon-bonded hydrogen atoms, along with a platinum catalyst. The platinum-catalyzed curing and foaming reactions proceed in two ways of, one, the hydrosilation between the vinyl groups in (A) and the silicon-bonded hydrogen atoms in (C) and, the other, by the dehydrogenation between the silanol groups in (B) and the silicon-bonded hydrogen atoms in (C). The composition gives a cured and foamed silicone rubber body having excellent mechanical properties with a good cell structure by standing at room temperature or by heating up to 70.degree. C.

Abstract: Novel organosilicon compounds of the following general formula ##STR1## in which R.sup.1 and R.sup.2 independently represent an unsubstituted or substituted monovalent hydrocarbon group having from 1 to 8 carbon atoms, R.sup.3 and R.sup.4 independently represent a hydrogen atom or have the same meaning as R.sup.1 and R.sup.2, X has the same meaning as R.sup.1 or is a group of the following formula ##STR2## in which R.sup.3 and R.sup.4 have, respectively, the same meanings as defined above, l and m are, respectively, 0, 1 or 2, and n is an integer of from 2 to 8.

Abstract: A gel composition which comprises a specific type of cyclic dimethyl polysiloxane, an animal or plant oil or vaseline, and an ester of dextrin with a fatty acid having from 8 to 20 carbon atoms. The cyclic dimethyl polysiloxane is methyl-substituted cyclotetrasiloxane, cyclopentasiloxane or cyclohexasiloxane. The use of this type of cyclosiloxane contributes to impart good spreadability on the skin to the composition.

Abstract: An improved aqueous electrolyte solution suitable as an electrolytic plating bath is disclosed which is capable of giving a magnetic layer of a cobalt-based alloy on a substrate of a magnetic recording medium used in a high-density vertical-mode magnetization. The electrolyte solution characteristically contains, in addition to the conventional salts of cobalt, manganese and nickel, reducing agent and pH buffering and controlling agents, a water-soluble rhenium salt such as ammonium perrhenate in a concentration of 0.002 to 0.015 mole/liter.

Abstract: Novel organo-silicone compounds represented by the formula, ##STR1## wherein R is hydrogen, halogen or alkyl group, R.sup.1, R.sup.2 and R.sup.3 are alkyl group, alkoxy group, phenyl radical, substituted phenyl radical, alkylcarbonyloxy group, or trialkylsilyloxy group, respectively, R.sup.4 is hydrogen, alkyl or alkenyl grup, and m and n are an integer, respectively but those do not represent same integer of 2, when all of R.sup.1, R.sup.2 and R.sup.3 represents methyl radical, a process for the manufacture of the compounds, and an anti-tumor agent which comprises as an effective component, at least one of the compounds.

Abstract: The invention provides a method for the preparation of a stable aqueous emulsion of a poly(silsesquioxane) without formation of gelled particles. In the method, a trialkoxysilane compound as the starting material is first emulsified in an aqueous medium containing a cationic surface active agent and a non-ionic surface active agent having a specified HLB value in the range from 16 to 20 in combination followed by the addition of an alkali catalyst and heating to effect hydrolysis and polycondensation of the trialkoxysilane.

Abstract: The single crystal wafer of lithium tantalate provided by the invention is characterized by the limited range of variation of the value of double refraction which should not exceed .+-.6.times.10.sup.-4 so that the value of the double refraction is given by 4.5.times.10.sup.-3 .+-.6.times.10.sup.-4. When single crystal wafers of lithium tantalate each satisfying the above requirements are used for the manufacture of SAW devices, the devices may have a very small deviation of the SAW sound velocity from the standard value and the range of variation of the SAW sound velocity within a wafer is also very small so that the SAW devices can be manufactured with greatly improved productivity and excellent quality.

Abstract: The invention provides an improvement in the suspension polymerization of vinyl chloride or a monomer mixture mainly composed of vinyl chloride in an aqueous medium containing a nonionic surface active agent and in the presence of a monomer-soluble polymerization initiator, according to which the aqueous polymerization medium is admixed with a crosslinked copolymer having carboxyl group such as a copolymer of acrylic acid and diethyleneglycol bisallyl or bismethallyl ether at a moment when the percentage of the monomer conversion is in the range from 1 to 20% so that a polyvinyl chloride resin product of high quality can be obtained having an outstandingly high bulk density and plasticizer absorptivity but still containing an extremely small number of fish eyes.