Abstract: This process is a process for production of a vinyl chloride polymer by suspension polymerization or emulsion polymerization of vinyl chloride monomer or a mixture of vinyl chloride monomer with a vinyl monomer copolymerizable with said vinyl chloride monomer in an aqueous medium, characterized in that the polymerization is carried out in a polymerizer, the inner wall surface and portions of the auxiliary equipment thereof which may come into contact with the monomer during polymerization being previously coated with a scaling preventive comprising at least one selected from dyes, pigments and aromatic or heterocyclic compounds having at least 5 conjugated .pi. bonds, while controlling the chloride ion concentration in the reaction mixture to not higher than 100 ppm. According to said process, scaling onto the inner wall surface of a polymerizer, etc. during polymerization can be prevented effectively and surely.

Abstract: The inventive composition is a silicone-based softening agent for synthetic fibers such as waddings of polyester fibers without the disadvantage of yellowing caused by heat or in the lapse of time. The essential ingredients of the inventive composition are a combination of two different amino-substituted organopolysiloxanes, an opoxy-containing alkoxysilane compound such as 3-glycidyloxypropyl methyl dimethoxy silane and a monoepoxy compound such as glycidyl alcohol each in a specified amount. Characteristically, one of the amino-substituted organopolysiloxane components is a reaction product of an amino-substituted organopolysiloxane and an organic opoxy compound.

Abstract: The inventive silicone grease composition has markedly improved lubrication characteristics under extreme-pressure conditions, greatly extended durability at high temperatures and little corrosiveness against metals in comparison with conventional silicone greases. The inventive silicone grease composition contains, in addition to an organopolysiloxane fluid as the base oil and a thickening agent, a specific chlorinated alicyclic compound 1,2,3,4,7,8,9,10,13,13,14,14-dodecachloro-1,4,4a,5,6a,7,10,10a,11,12,12a-d odecahydro-1,4;7,10-dimethanodibenzo [a,e] cyclooctane in a substantial amount.

Abstract: The x-cut single crystal wafer of lithium tantalate according to the invention is characterized by the orientation flat formed in a specific crystallographic orientation. The plane of the orientation flat should be (A) in parallel with the (018) plane or a plane which is in parallel with the x-axis and makes an angle of 15.degree. or smaller with the (018) plane or (B) in parallel with a plane which is in parallel with the x-axis and perpendicular to the (018) plane or a plane which is in parallel with the x-axis and makes an angle of 15.degree. or smaller with the plane which is in parallel with the x-axis and perpendicular to the (018) plane. In contrast to conventional lithium tantalate single crystal wafers provided with an orientation flat in a direction parallel to the 112.degree.

Abstract: A silicone rubber composition suitable for hot-air vulcanization under normal pressure without the disadvantages of surface tackiness and internal voids in the cured rubber products and also free from the problems of corrosiveness to metals and toxicity to workers, which comprises, as the curing agent for the organopolysiloxane, a peroxide derivative of dibenzoyl peroxide which is substituted on each of the benzene nuclei with substituted silyl, e.g. trimethyl silyl, group or a silyl-substituted methyl, e.g. trimethylsilyl methyl, group.

Abstract: The rubber composition without formulating a carbon black filler has a remarkably low Mooney viscosity and still is capable of giving a rubber vulcanizate having excellent mechanical properties. The rubber composition comprises, in addition to natural rubber or a diene-based synthetic rubber and a non-carbon inorganic filler, a specific poly(dialkoxysiloxane) terminated at each molecular chain end with a polysulfide linkage-containing group of the formula (RO).sub.3 Si--R.sup.1 --S.sub.x -- R.sup.1 --bonded to the terminal silicon atom, in which R is an alkyl group, e.g. methyl and ethyl, R.sup.1 is a divalent hydrocarbon group, e.g. --CH.sub.2 CH.sub.2 CH.sub.2 13 , and x is a positive integer of 2 to 6 or, typically, 4.

Abstract: The invention provides organosilane compounds of a novel class having one or two (phenyl dimethyl carbinyl) groups bonded to the silicon atom as represented by the general formula (PhMe.sub.2 C).sub.p R.sub.q X.sub.r Si, in which Ph is a phenyl group, Me is a methyl group, R is a monovalent hydrocarbon group selected from the class consisting of alkyl, alkenyl and aryl groups, X is a halogen atom or an alkoxy group, p is 1 or 2, q is zero, 1 or 2 and r is zero, 1, 2 or 3 with the proviso that p+q+r=4. The compound can be prepared by the reaction of a Grignard reagent PhMe.sub.2 C. MgY, in which Y is a halogen atom, with a silane compound represented by the general formula R.sub.q SiX.sub.4-q in an organic solvent.

Abstract: A synthetic resin modifier comprising an organopolysiloxane represented by General Formula (I): ##STR1## wherein the group represented by X consists of 2 to 40% by weight of a group represented by R.sup.1 CO--, wherein R.sup.1 represents a saturated or unsaturated monovalent hydrocarbon group having 7 to 21 carbon atoms, and 60 to 98% by weight of a group represented by R.sup.2 --O-C.sub.q H.sub.2q), wherein R.sup.2 represents a saturated or unsaturated monovalent hydrocarbon group having 7 to 21 carbon atoms.This modifier can be effective for any type of synthetic resins, imparting good lubricity and release properties to the surface of forms or molding products, including films, and improving the workability in the molding of synthetic resins.

Abstract: The silicone rubber composition comprises, in addition to the conventional ingredients of a high-polymeric diorganopolysiloxane and a reinforcing silica filler, a specific phosphorus-containing organic compound, such as phosphinates, phosphonates and phosphates, in a limited amount. By virtue of this unique ingredient, the composition can give a cured silicone rubber product having greatly improved resistance against dynamic fatigue.

Abstract: A presensitized plate for use in making a planographic printing plate requiring no dampening water which comprises a support having provided thereon, in order, a light-sensitive layer comprising a photodimerizable resin and a silicone rubber layer comprising an organopolysiloxane cured with a crosslinking agent comprising a reactive silane compound having a carbon-carbon double bond to which a silicon atom is not directly linked. The presensitized plate shows excellent developing properties and fine dot reproduction.

Abstract: A curable fluorosilicone rubber composition comprising particular organopolysiloxane having a fluoroalkyl group and having a viscosity of 1,000 cP or more at 25.degree. C., reinforcing silica powder having a specific surface area of 50 m.sup.2 /g or more, and a vulcanizing agent; which further comprises, as a fluid for bleed, a fluid organopolysiloxane compound represented by General Formula: ##STR1## wherein some R' represent methyl groups and other R' represent phenyl groups; the ratio of the number of the methyl group to the number of the phenyl group in the molecule ranges between 70/30 and 25/75; and n is an integer of 0 to 5.Rubber obtained by curing of this composition has excellent oil and solvent resistance, thermal resistance and low-temperature resistance which are inherent in ordinary fluorosilicone rubber, and moreover has a good fluid-bleeding property.

Abstract: The silicone-based antifoam composition having excellent durability of the antifoam activity even under vigorous agitation or under an alkaline condition comprises three kinds of diorganopolysiloxanes, of which the first is free from aliphatic unsaturation, the second is terminated at both molecular chain ends each with a vinyl diorganosilyl group and the third is terminated at both molecular chain ends each with a diorganosilyl group having a silicon-bonded hydrogen atom, a finely divided silica powder, a platinum compound to catalyze the addition reaction between the silicon-bonded vinyl groups and silicon-bonded hydrogen atoms in the second and the third diorganopolysiloxanes, respectively, and an organosilane compound of the formula R.sup.1.sub.a Y.sub.b Si, in which R.sup.1 is a monovalent hydrocarbon group, Y is a hydroxy, carboxyl or hydrolyzable group and a and b are each 1, 2 or 3 with the proviso that a+b=4.

Abstract: A novel methacrylic acid ester represented by General Formula (I): ##STR1## wherein l is an integer of 1 to 3; m is an integer of 1 to 10; and n is an integer of 1 to 3,and a process for producing the same. This novel methacrylic acid ester is useful for the synthesis of polymers having useful functions such as an oxygen enrichment performance.

Abstract: The curable organopolysiloxane composition of the invention is formulated with two kinds of crosslinking agents including an organosilane compound having 2 or 3 isopropenyloxy groups in a molecule and an organopolysiloxane having at least 2 mercapto groups in a molecule added to the base ingredient of a hydroxy-terminated diorganopolysiloxane together with a curing catalyst and a photosensitizer. The composition has two-way curability by the condensation reaction in the presence of atmospheric moisture between the silanolic hydroxy groups and the isopropenyloxy groups and by the ultraviolet-induced addition reaction between the isopropenyloxy groups and the mercapto groups to exhibit very reliable curing behavior giving a cured rubbery elastomer having excellent properties.

Abstract: A novel method is proposed for the synthesis of an organopolysiloxane having two hydrogen atoms directly bonded to the same silicon atom at the molecular chain end. The method comprises mixing a dihydro isopropenyloxy silane with an organosilicon compound having at least one silanolic hydroxy group so that a condensation reaction takes place between the isopropenyloxy group of the former reactant and the silanol group of the latter reactant forming acetone as a by-product. The method is advantageous in respect of the absence of any acidic or basic by-product contained in the product as an impurity in the conventional methods.

Abstract: A crosslinkable copolymer is prepared by the copolymerization of a first ethylenically unsaturated monomer and a second monomer substituted by a vinyl-containing cyclic organosilicon group such as ##STR1## in which Vi and Me denote vinyl and methyl groups, respectively. When such a copolymer is admixed with a crosslinking agent such as an organic peroxide and shaped with heating, the crosslinkable copolymer is crosslinked so that the shaped article is imparted with greatly improved properties.

Abstract: The inventive organopolysiloxane composition is curable in two ways, firstly, by the irradiation with ultraviolet light and, secondly, by exposure to a moisture-containing atmospheric air. The principal ingredient of the composition is a diorganopolysiloxane having, in a molecule, at least one isopropenyloxysilyl-substituted ethyl or propyl group bonded to the silicon atom of the polysiloxane chain, which is compounded with a mercaptoalkyl-containing organopolysiloxane, a photosensitizer and, optionally, a curing catalyst for the dealcoholation condensation reaction of the silicon-bonded alkoxy groups under the influence of atmospheric moisture. The composition is advantageous in the improved workability by virtue of the adequate tack-free time or the time taken for surface filming.

Abstract: An efficient cost- and labor-saving method is proposed for controlling the population of two kinds or more of different species of insectan pests in a field by means of distributing dispensers of sex pheromone compounds for the respective species of the insects when one of the sex pheromone compounds is an unsaturated C.sub.10 to C.sub.12 alcohol and the other is an unsaturated C.sub.14 to C.sub.20 acetate or aldehyde. When these two classes of the compounds are mixed in such a proportion that the overall solubility paramater .delta. of the mixture is 9.1 to 9.7 and the mixture is contained in a dispenser body made of polyethylene or a copolymer mainly composed of ethylene moiety, the two compounds can be concurrently emitted from the dispenser in the form of vapor each at a controlled rate over a desired length of time.

Abstract: Described is a magnetic recording medium comprising a non-magnetic substrate and a magnetic layer formed thereon composed mainly of magnetic powder and a binder, said binder containing a compound represented by a following formula: ##STR1## wherein X represents tertiary amine sulfonate or tertiary amine sulfuric ester, Y represents a monomer having vinyl group which is copolymerizable with vinyl chloride and i, j, k represent polymerization degrees.

Abstract: N-Methyl-N-trimethylsilyl trifluoroacetamide can be synthesized by the reaction of N-methyl trifluoroacetamide and, N,O-bis(trimethylsilyl) acetamide at 40.degree.-130.degree. C. followed by fractionating distillation. The method is advantageous in respect of the absence of the step of filtration for the removal of the by-product salt and non-use of any corrosive reactant in comparison with conventional methods.