Abstract: Fine silica particles surface-treated with a silane and having primary particles having a particle diameter of from 0.01 to 5 ?m, which fine silica particles fulfill the following conditions (i) and (ii), a process for their production and an organic resin composition containing such particles as a component are provided. (i) When an organic compound which is liquid at room temperature and has a dielectric constant of from 1 to 40 F/m and fine silica particles are mixed in a weight ratio of 5:1 and shaked, the fine silica particles disperse uniformly in the organic compound, and (ii) the quantity of primary particles remaining as primary particles when methanol is evaporated under heating by means of an evaporator from a dispersion prepared by dispersing the fine silica particles in methanol and thereafter the particles are held at a temperature of 100° C. for 2 hours, is in a percentage of at least 20% based on the quantity of primary particles originally present.

Abstract: A process for preparing an urethane compound for medical instruments, characterized by reacting a hydroxyl compound (A) with an isocyanate compound (B) in the absence of a catalyst or in the presence of a reaction catalyst other than an organic tin compound to give an urethane compound (I). According to the process, the urethane compound showing high safety can be easily prepared, in particular, while molecular weight of the compound is controlled.

Abstract: A process for preparing an ocular lens with a urethane compound comprising the steps of a) preparing a urethane compound by reacting at least one hydroxyl compound and at least one isocyanate compound in the presence of an organic iron compound, b) removing the organic iron compound from the urethane compound obtained in the step a) c) mixing the urethane compound obtained in the step b) with at least one compound selected from the group consisting of another copolymerizable compound, a crosslinking agent, a UV absorbent, a dye, a polymerization initiator, a photosensitizer, and an organic solvent to obtain a mixture, and d) curing the mixture obtained in the step c) to prepare a lens.

Abstract: A polyethersilicone represented by the following formula (1), said polyethersilicone being modified at an end of a silicone chain thereof, 1

Abstract: Coatings composed of (A) a copolymer prepared by copolymerizing (1) a silicone macromer having a double bond at one end of the molecule, (2) an unsaturated monomer having on the molecule both a carboxyl or acid anhydride group and a double bond, (3) an unsaturated silane monomer having on the molecule both a hydrolyzable silyl group and a double bond, (4) an unsaturated monomer having on the molecule both an amide, imide, carbamate or urea group and a double bond and, optionally, (5) another copolymerizable unsaturated monomer; in combination with (B) a crosslinking catalyst provide crosslinked coats which have an adhesion to substrates and a toughness comparable to isocyanate-crosslinked coats and which are also endowed with excellent lubricity.

Abstract: Fine silica particles surface-treated with a silane and having primary particles having a particle diameter of from 0.01 to 5 &mgr;m, which fine silica particles fulfill the following conditions (i) and (ii), a process for their production and an organic resin composition containing such particles as a component are provided. (i) When an organic compound which is liquid at room temperature and has a dielectric constant of from 1 to 40 F/m and fine silica particles are mixed in a weight ratio of 5:1 and shaked, the fine silica particles disperse uniformly in the organic compound, and (ii) the quantity of primary particles remaining as primary particles when methanol is evaporated under heating by means of an evaporator from a dispersion prepared by dispersing the fine silica particles in methanol and thereafter the particles are held at a temperature of 100° C. for 2 hours, is in a percentage of at least 20% based on the quantity of primary particles originally present.

Abstract: A process for preparing an ocular lens with a urethane compound comprising the steps of

Abstract: A carnuba silicone wax which does not contain free silicone oil. This wax is obtained by reacting a silicone compound having a substituent with reactivity to the hydroxyl group in natural carnuba wax, with this hydroxyl group. A carboxyl group may be introduced into the molecule by reacting this hydroxyl group with a cyclic acid anhydride, and a silicone compound having a group which can react directly with this carboxyl group is made to react. Alternatively, a hydrogen silicone may be hydrosilylated by a double bond introduced by reacting an epoxy compound having a double bond with this carboxyl group.

Abstract: A silicone wax which has a melting point of 45° C. or more, and an endothermic peak half value amplitude in a scanning differential calorimeter measurement of 7° C. or less is disclosed. This silicone wax is easily obtained by a reaction between the reaction product of a higher fatty acid of purity 90% or higher, and/or a higher alcohol of purity 90% or higher and a double bond-containing compound, and one or more compounds chosen from among a SiH bond-containing silicone compound, an amino group-containing silicone compound and a sulfhydryl group-containing compound, or by a dehydration reaction between a higher fatty acid of purity 90% or higher and an amino group-containing silicone compound.

Abstract: A process for preparing an urethane compound for medical instruments, characterized by reacting a hydroxyl compound (A) with an isocyanate compound (B) in the absence of a catalyst or in the presence of a reaction catalyst other than an organic tin compound to give an urethane compound (I). According to the process, the urethane compound showing high safety can be easily prepared, in particular, while molecular weight of the compound is controlled.

Abstract: The present invention is a cosmetic material characterized by comprising silicone-modified wax wherein low-molecular-weight polyethylene and/or low-molecular-weight polypropylene is linked to silicone via ester linkage.

Abstract: Fine silica particles surface-treated with a silane and having primary particles having a particle diameter of from 0.01 to 5 &mgr;m, which fine silica particles fulfill the following conditions (i) and (ii), a process for their production and an organic resin composition containing such particles as a component are provided. (i) When an organic compound which is liquid at room temperature and has a dielectric constant of from 1 to 40 F/m and fine silica particles are mixed in a weight ratio of 5:1 and shaked, the fine silica particles disperse uniformly in the organic compound, and (ii) the quantity of primary particles remaining as primary particles when methanol is evaporated under heating by means of an evaporator from a dispersion prepared by dispersing the fine silica particles in methanol and thereafter the particles are held at a temperature of 100° C. for 2 hours, is in a percentage of at least 20% based on the quantity of primary particles originally present.

Abstract: Coatings composed of (A) a copolymer prepared by copolymerizing (1) a silicone macromer having a double bond at one end of the molecule, (2) an unsaturated monomer having on the molecule both a carboxyl or acid anhydride group and a double bond, (3) an unsaturated silane monomer having on the molecule both a hydrolyzable silyl group and a double bond, (4) an unsaturated monomer having on the molecule both an amide, imide, carbamate or urea group and a double bond and, optionally, (5) another copolymerizable unsaturated monomer; in combination with (B) a crosslinking catalyst provide crosslinked coats which have an adhesion to substrates and a toughness comparable to isocyanate-crosslinked coats and which are also endowed with excellent lubricity.

Abstract: A process for preparing an urethane compound for medical instruments, characterized by reacting a hydroxyl compound (A) with an isocyanate compound (B) in the absence of a catalyst or in the presence of a reaction catalyst other than an organic tin compound to give an urethane compound (I). According to the process, the urethane compound showing high safety can be easily prepared, in particular, while molecular weight of the compound is controlled.

Abstract: A cosmetic containing spherical hydrophobic fine silica particles having an average particle diameter of from 0.01 to 5 &mgr;m, having been made more highly hydrophobic, is provided. The spherical hydrophobic fine silica particles have been made hydrophobic on their surfaces by introducing an R2SiO3/2 unit (wherein R2 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms) to the surfaces of hydrophilic fine silica particles having an SiO2 unit, and further have been made more highly hydrophobic on their surfaces by introducing to the surfaces of the hydrophobic fine silica particles first treated an R13SiO1/2 unit (wherein R1's may be the same or different and each represent a monovalent hydrocarbon group having 1 to 6 carbon atoms). The cosmetic containing spherical hydrophobic fine silica particles is a product improved in spreadability and inunctionability.

Abstract: An external additive for electrostatically charged latent image developing toner is provied. The additive includes spherical hydrophobic fine silica particles having primary particles having a particle diameter of from 0.01 to 5 &mgr;m, which fine silica particles fulfill the following conditions (i) and (ii): (i) when an organic compound which is liquid at room temperature and has a dielectric constant of from 1 to 40 F/m and fine silica particles are mixed in a weight ratio of 5:1 and shaken, the fine silica particles disperse uniformly in the organic compound; and (ii) the quantity of primary particles remaining as primary particles when methanol is evaporated under heating by means of an evaporator from a dispersion prepared by dispersing the fine silica particles in methanol and thereafter the particles are held at a temperature of 100° C. for 2 hours, represents at least 20% of the quantity of primary particles originally present.

Abstract: A mixture of short-chain polysulfide silanes of the formula: (RO).sub.3 SiC.sub.3 H.sub.6 S.sub.n C.sub.3 H.sub.6 Si(OR).sub.3 wherein R is methyl or ethyl and n is a positive number having a distribution whose average falls in the range: 2.2.ltoreq.n.ltoreq.2.8 is prepared by reacting metal polysulfides, typically Na.sub.2 S.sub.n with a halogenopropyltrialkoxysilane of the formula: (RO).sub.3 SiC.sub.3 H.sub.6 X wherein X is halogen.

Abstract: A mixture of short-chain polysulfide silanes having the formula: (RO).sub.3 SiC.sub.3 H.sub.6 S.sub.n C.sub.3 H.sub.6 Si(OR).sub.3 wherein R is methyl or ethyl and n is a positive number having a distribution in the average range of 2.1.ltoreq.n.ltoreq.2.9, is prepared by reacting one mole of an anhydrous sulfide of the formula: M.sub.2 S or NS wherein M is an alkali metal or ammonium and N is an alkaline earth metal or zinc, with (n-1) mole of sulfur in an inert gas atmosphere and in a polar solvent, thereby forming polysulfide compounds, and reacting the polysulfide compounds with a halogenopropyltrialkoxysilane of the formula: (RO).sub.3 SiC.sub.3 H.sub.6 X wherein R is as defined above and X is a halogen atom. The method is simple to produce polysulfide silanes in high yields.

Abstract: Water-soluble organic silicon compounds are prepared by effecting co-hydrolysis of (A) 1-30 parts of an alkyltrialkoxysilane of R.sup.1 Si(OR.sup.2).sub.3 or a partial hydrolyzate thereof, (B) 70-90 parts of an alkoxy-containing siloxane of R.sup.3.sub.a (OR.sup.2).sub.b SiO.sub.(4-a-b)/2, and (C) 1-20 parts of an amino-containing alkoxysilane of R.sup.4 R.sup.5 NR.sup.6 --SiR.sup.7.sub.n (OR.sup.2).sub.3-n or a partial hydrolyzate thereof in the presence of an organic or inorganic acid. R.sup.1 is a C.sub.7 -C.sub.18 alkyl group, R.sup.2 is a C.sub.1 -C.sub.4 alkyl group, R.sup.3 is a C.sub.1 -C.sub.6 alkyl group, R.sup.4 and R.sup.5 are a hydrogen atom, C.sub.1 -C.sub.15 alkyl or aminoalkyl group, R.sup.6 is a divalent C.sub.1 -C.sub.18 hydrocarbon group, and R.sup.7 is a C.sub.1 -C.sub.4 alkyl group. Letters a and b are 0.75.ltoreq.a.ltoreq.1.5, 0.2.ltoreq.b.ltoreq.2, and 0.95<a+b<3.4.

Abstract: Polysulfide silanes: (RO).sub.3 SiC.sub.3 H.sub.6 S.sub.x C.sub.3 H.sub.6 Si(OR).sub.3 are reacted with an anhydrous sulfur compound: M.sup.1.sub.2 S or M.sup.2 S and a halogenoalkoxysilane: XC.sub.3 H.sub.6 Si(OR).sub.3 to form polysulfide silanes: (RO).sub.3 SiC.sub.3 H.sub.6 S.sub.y C.sub.3 H.sub.6 Si(OR).sub.3 wherein R is methyl or ethyl, x is a positive number of 3 to 6 on the average, M.sup.1 is an alkali metal or ammonium, M.sup.2 is an alkaline earth metal or zinc, X is a halogen, and y is a positive number less than x on the average. Short chain polysulfide silanes can be prepared with the industrial advantages of safety, high yields and low cost.