Abstract: A loop portion of a bus wire connected to an electric blasting device is passed through a first magnetic core together with a first loop-like wire, and the first loop-like wire is further passed through a second magnetic core provided in a detonator. The detonator includes a second loop-like wire which is passed through the second magnetic core, an electric bridge connected to the second loop-like wire and a fuse head provided around the electric bridge. When a pulsatory high frequency current is supplied to the bus wire, high frequency currents are induced in the first and second loop-like wires by electromagnetic induction. Then the current flows through the electric bridge of the detonator to fire the primer explosive.

Abstract: An ethylene-acrylic acid ester copolymer can be easily grafted in a high graft efficiency with a peroxy group-containing block copolymer consisting of segments of copolymer A, which is a copolymer of a (meth)acrylic acid ester monomer or its mixture with a radically copolymerizable monomer, with a radically copolymerizable peroxycarbonate, and segments of (co)polymer B, which is different from copolymer A in the monomer composition and does not contain a monomer unit of the radically copolymerizable peroxycarbonate. The grafted ethylene-acrylic acid ester copolymer can be effectively used as a compatibilizing agent in a polymer blend of polyolefin with styrene (co)polymer, as an emulsifying agent in an emulsion of high polymer, or as an adhesive at the interface of polyolefin and styrene (co)polymer.

Abstract: A light curable dental composition is provided. The composition comprises an ethylenic unsaturated compound and a light polymerization initiator. The light polymerization initiator is selected from a combination of an organic peroxide and a pyrylium salt compound of: ##STR1## Wherein R.sub.1, R.sub.2, and R.sub.3 each represents a hydrogen atom, an alkyl group and the like, X stands for an oxygen or sulfur atom and Y for an anionic functional group; a polyperoxy ester containing a benzophenone group; and a combination the polyperoxy ester and an .alpha.-diketone.

Abstract: A composition for semiconductor porcelain comprisies:(a) 35.5 to 70 mol % of MgTiO.sub.3,(b) 26.5 to 61 mol % of BaTiO.sub.3,(c) a grain boundary improver, and(d) 0.01 to 0.2 mol % of an element selected from rare earth elements and the elements belonging to the group V of the periodic table.

Abstract: An aqueous suspension of a solid organic peroxide is produced by mixing a solid organic peroxide having a difference of at least 5.degree. C. between the melting point and the thermal decomposition temperature thereof with a protective colloid, a surface active agent, and water thereby forming an aqueous emulsion and subsequently cooling this aqueous emulsion.

Abstract: A water-in-oil emulsion explosive having a high resistance against dead pressing is obtained by adding a cushioning medium having a high impact energy-absorbing property to a water-in-oil emulsion explosive containing a continuous phase consisting of a carbonaceous fuel, a disperse phase consisting of an aqueous solution of inorganic oxidizer salt and an emulsifier.

Abstract: A resin composition with which to coat a steel structure used as a reinforcement, in a lightweight foam concrete produced under the condition of high temperature, high pressure and high alkalinity. The resin composition with which to coat a steel structure comprises a phenoxy resin and a hardening agent having a blocked isocyanate group.

Abstract: Amorphous alloy shaped articles having excellent magnetic properties, high hardness and strength, or high corrosion resistance can be obtained by a method, wherein amorphous alloy or atomized alloy raw material powder layer is laminately arranged adjacently to a metal powder layer having a shock impedance a little different from that of the raw material powder layer, and a shock pressure is applied to the raw material powder layer.

Abstract: A method of preparing fine crystal particles of maleic anhydride is provided. The method contains the steps of putting a molten mass of maleic anhydride into a hermetically closed container moved at a moving rate of 1 to 30 times per minute and cooling the molten mass to room temperature over three hours or more. A maleic anhydride composition contains 0.01 to 5 wt. parts of colloidal silica relative to 100 wt. parts of maleic anhydride particles.

Abstract: A cured unsaturated polyester resin or vinyl ester resin having excellent water resistance, weather resistance, stain resistance and anti-block property can be obtained by curing an unsaturated polyester resin or vinyl ester resin together with a fluorine-containing block copolymer consisting of a polymer portion having fluorine-containing groups and a polymer portion compatible with the unsaturated polyester resin or vinyl ester resin.

Abstract: A method for finish coating on polyurethane formed articles, which comprises formulating a finish coating composition so as to have a content of pyrrolidone or its derivative represented by the general formula ##STR1## in which R stands for hydrogen or an alkyl group having at the most 4 carbon atoms, in an amount of 5-40% by weight upon the coating, applying this finish coating composition on the polyurethane formed article directly and heating the so called polyurethane formed article at a temperature of at least 50.degree. C.

Abstract: Expandable thermoplastic resin particles comprising a thermoplastic resin and a hydrocarbon having the lower boiling point than the softening point of the thermoplastic resin in which a copolymer composed of a fluorinated vinyl polymer part and a hydrophilic vinyl polymer part covers or is included on the surface or in the surface layer of the expandable thermoplastic particle, said resin particles are useful for producing package vessels and containers for oily or fatty foods.

Abstract: A drill bit the point of which has two or more outer cutting edges and is formed with a V-shaped notch. The V-shaped notch has its center lying on the axis of rotation of the drill bit and opens in the direction of feed of the tool. The V-shaped notch defines inner cutting edges terminating in respective outer cutting edges.

Abstract: According to the invention, a method for modifying a polyfumaric acid diester is provided. The method comprises subjecting the polyfumaric acid diester to thermal treatment to thereby obtain a polyfumarate having carboxyl groups. The polyfumaric acid diester is obtained by polymerizing a fumaric acid diester represented by the following general formula of: ##STR1## wherein R represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms or an organic residue having at least one aromatic ring.

Abstract: A block copolymer consisting of segments of copolymer A, which is obtained by copolymerizing an aromatic vinyl monomer with a radically copolymerizable peroxycarbonate and has peroxy groups in its main polymer chain, and segments of (co)polymer B, which is different from copolymer A in the monomer composition and does not contain peroxy groups, can modify matrix resin without deteriorating the mechanical property of the resin.

Abstract: A specialized polymeric peroxide is copolymerized with vinyl type monomers in the presence of organic liquid, thereby obtaining a solution of a copolymer having peroxy bonds therein.This solution is admixed with vinyl type monomers which are different in composition from the ones used in the first copolymerization, and the resultant mixture is subjected to block copolymerization.The obtained block copolymer solution is admixed with an organic liquid which exert solubility to one of polymers of the vinyl type monomers which are employed in the first or second copolymerization, whereby a non aqueous system liquid dispersion is obtained.This dispersion contains a block copolymer in a high concentration and it also is splendid in uniformity of dispersion and dispersion stability.

Abstract: A random copolymer comprising specific groups represented by the general formula: ##STR1## and specific peroxycarbonate structural units represented by the general formula: ##STR2## is produced by a method which comprises causing a compound of the formula: ##STR3## to react with a compound of the formula: ##STR4##

Abstract: A lubricating oil composition for metal rolling is described, comprising (a) an oily component comprising one or more of fats and oils, mineral oils, and fatty acid esters, and (b) a dispersant comprising one or more of polyethyleneimine/epoxy compound adducts, polyethylene polyamine/epoxy compound adducts, fatty acid esters of the adducts, and salts of the adducts and the fatty acid esters. This composition is useful for rolling metals under high shear and high rolling speed conditions.

Abstract: A pressure-resistant buoyancy material, comprising pressure-resistant hollow elements, a syntactic foam, and an empty space intervening between the pressure-resistant hollow elements and the syntactic foam, communicating with the outside of the buoyancy material. The pressure-resistant hollow elements are retained in a freely movable state in the empty space.

Abstract: It is proposed a hair-rinse liquid having pearly luster, which includes the following four components A to D, namely:component A: a cationic surface active agent expressed by the general formula (I), as given below;component B: an amine oxide represented by the general formula (II), as given also in below;component C: an amino acid having an isoelectric point not higher than 7 andcomponent D: a salt of an alkali metal or alkaline earth metal. ##STR1## In the above formulae (I) and (II), R.sup.1, R.sup.2, R.sup.3 and R.sup.4 represent each a hydrocarbon group or a hydroxy alkyl group having 1-24 carbon atoms, which may be identical or different with each other, and the sum of the total carbon atoms in each formula should lie within the range of 16-45 and X denotes a halogen atom.