Abstract: It is an object of the present invention to provide a dimer diol derivative and a composition containing the dimer diol derivative which have an excellent water-holding property, an excellent pigment dispersion property and further a high level of safety.

Abstract: A spark plug comprises: a center electrode (3); an insulator (2) provided around the center electrode (3); a metal shell (1)provided around the insulator (2); a ground electrode (4) disposed in opposition to the center electrode (3) so as to form a spark discharge gap; and a sealing-material layer (61) comprising a sealing material, wherein the sealing material comprises talc, and the sealing material is filled in a space between the inner face of the metal shell (1) and the outer face of the insulator (2), so as to seal the space, wherein the sealing material has a filling density of 1.5 g/cm3 to 3.0 g/cm3, or the sealing-material layer (61) comprises at least one of an inorganic material and a silicone binder in an amount of 2 to 7 wt %.

Abstract: A spark plug comprises: a center electrode (3); an insulator (2) provided around the center electrode (3); a metal shell (1) provided around the insulator (2); a ground electrode (4) disposed in opposition to the center electrode (3) so as to form a spark discharge gap; and a sealing-material layer (61) comprising a sealing material, wherein the sealing material comprises talc, and the sealing material is filled in a space between the inner face of the metal shell (1) and the outer face of the insulator (2), so as to seal the space, wherein the sealing material has a filling density of 1.5 g/cm3 to 3.0 g/cm3, or the sealing-material layer (61) comprises at least one of an inorganic material and a silicone binder in an amount of 2 to 7 wt %.

Abstract: A process for growing a single crystal in which variation in a dopant concentration in a melt contained in a crucible can be reduced and a single crystal having small variation in specific resistance can be produced. The process is the Czhohralski growth of a silicon single crystal including the steps: melting a crystal raw material in a crucible; bringing into contact a seed crystal to a melt contained in the crucible to thereby stabilize the surface temperature of the melt that is called “the seed crystal contact technique;” and adding a dopant into the crucible after carrying out the seed crystal contact technique. Furthermore, in the process, a dopant may be added while the seed crystal contact technique is stopped, and the seed crystal contact technique may be carried out again. Alternatively, a dopant may be added while the seed crystal contact technique is carried out.

Abstract: The invention provides a spark plug having an insulator which is composed mainly of alumina, and which is more superior in voltage endurance characteristics at high temperatures as compared with the prior-art materials. An insulator 2 of a spark plug 100 is made of an insulating material which is composed mainly of alumina, and which contains Al component within a range of 95 to 99.7 wt % in weight converted to Al2O3, and in which an area ratio occupied by alumina base principal-phase particles with particle size not less than 20 &mgr;m is not less than 50% as a cross-sectional structure of the insulator is observed. By making the alumina base principal-phase particles appropriately coarse like this, the voltage endurance characteristics of the insulator can be remarkably improved.

Abstract: In a spark plug insulator made of a sintered ceramic body, including aluminum nitride (AlN) or aluminum oxynitride (AlON) ceramic powder having an average grain size of 1.5 .mu.m in which the oxygen content of the aluminum nitride or the aluminum oxynitride powder is less than 2 percent by weight. Magnesium (Mg) is also present in an amount in the range from 0.01 wt. % to 5.0 wt. % where the amount of the magnesium (Mg) is calculated by converting the magnesium (Mg) to its oxidized compound (MgO). Also included is a sintering additive present in an amount up to 10 wt. % selected from the group consisting of rare earth metal compounds in which the weight percentage of the sintering additive is calculated by converting the sintering additive to its oxidized compound. The rare earth metal compound is selected from the group of yttrium oxide (Y.sub.2 O.sub.3) calcium oxide (CaO), barium oxide (BaO), strontium oxide (SrO), scandium oxide (Sc.sub.2 O.sub.2), europium oxide (Eu.sub.2 O.sub.

Abstract: An organic composite coated steel sheet having excellent chromate dissolution resistance, wet adhesion, and corrosion resistance before and after working. The steel sheet comprises a chromate-silica film on at least one face of a zinc or zinc base alloy plated steel sheet, the silica-added chromate film having about 5 to 500 mg/m.sup.2 in terms of metal Cr content and being formed from a chromate solution containing about 25 to 70 wt % of Cr.sup.+6 based upon total Cr content. A resin coating film is adhered to the chromate-silica film and is formed from an aqueous paint. The aqueous paint includes an aqueous anionic resin and/or an aqueous nonionic resin, a reducing agent, and a water-dispersed silica. The resin coating film is deposited in a dry weight amount of about 0.1 to 3 g/m.sup.2.

Abstract: In a spark plug insulator having a sintered ceramic body, the ceramic body has silicon nitride (Si.sub.3 N.sub.4), aluminum nitride (AlN) and alumina (Al.sub.2 O.sub.3), the sum of the weight of aluminum nitride (AlN) and alumina (Al.sub.2 O.sub.3) to silicon nitride (Si.sub.3 N.sub.4) is in the range of 0.093.about.1.439. Typically, the additive is represented by the group consisting of yttrium oxide (Y.sub.2 O.sub.3), calcium oxide (CaO), lanthanum oxide (La.sub.2 O.sub.3), magnesia (MgO), cerium oxide (SrO), barium oxide (BaO) and neodymium (Nd.sub.2 O.sub.3). The percentage by weight of the sintering additive ranges from 0.3% to 15.0% of the total weight of the silicon nitride (Si.sub.3 N.sub.4), aluminum nitride (AlN) and alumina (Al.sub.2 O.sub.3).

Abstract: In a spark plug insulator for use in an internal combustion engine, a sintered body has boron nitride and a metal oxide, the boron nitride of the sintered body being 80% or exceeding 80% by weight, and the sintered body having a thermal expansion coefficient of less than 5.0.times.10-.sup.6 /.degree.C. The metal oxide is selected alone or combination from the group consisting of magnesium oxide, calcium oxide, silicon oxide, boron oxide, yttrium oxide and aluminum oxide.

Abstract: In a spark plug insulator for use in an internal combustion engine, a sintered body has boron nitride and a metal oxide, the boron nitride of the sintered body being 80% or greater by weight, and the sintered body having a thermal expansion coefficient of less than 5.0.times.10-.sup.6 /.degree.C. The metal oxide is selected alone or in combination from the group consisting of magnesium oxide, calcium oxide, silicon oxide, boron oxide, yttrium oxide and aluminum oxide.

Abstract: A spark plug includes a cylindrical metallic shell having a shoulder portion, and a tubular insulator having a stepped portion which rests on the shoulder portion within the metallic shell. The insulator has a rear half made of aluminum oxide and a front half made of aluminum nitride, the rear half having a protrusion, while the front half having a housing, and tightly joining the protrusion within the housing. An overlapping portion of the protrusion and the housing is at least partly located in a plane which is perpendicular to a longitudinal axis of the center electrode, the plane passing through the shoulder portion of the metallic shell.

Abstract: In a spark plug insulator having a sintered ceramic body, the ceramic body has silicon nitride (Si.sub.3 N.sub.4), aluminum nitride (AlN) and alumina (Al.sub.2 O.sub.3), the weight ratio of aluminum nitride (AlN) and alumina (Al.sub.2 O.sub.3) to silicon nitride (Si.sub.3 N.sub.4) being in the range of 0.093 to 1.439; and at least one sintering additive is among the group consisting of yttrium oxide (Y.sub.2).sub.3), calcium oxide (CaO), lanthanum oxide (La.sub.2 O.sub.3), magnesia (MgO), cerium oxide (CeO.sub.2), scandium oxide (Sc.sub.2 O.sub.3), strontium oxide (SrO), barium oxide (BaO) and neodymium (Nd.sub.2 O.sub.3). The weight percentage of the sintering additive ranges from 0.3% to 15.0% of the total weight of the silicon nitride (Si.sub.3 N.sub.4), aluminum nitride (AlN) and alumina (Al.sub.2 O.sub.3).

Abstract: A spark plug insulator is desirably made up of a sintered body of AlN-based ceramic powder comprising about 60-98% AlN and a sintering additive. There is provided on the surface of the sintered body a layer of pyrolytic boron nitride having a thickness in the range 10-100 .mu.m.

Abstract: In a sintered ceramic body used for an insulator of a spark plug, magnesium (Mg) is uniformly diffused into grains of a nitride-based ceramic body. An amount of the diffused magnesium (Mg) is within a range from 20 ppm to 100 ppm which is calculated by reducing the magnesium (Mg) to its oxidized component.

Abstract: Disclosed is an anti-corrosive coating composition comprising (a) 100 parts by weight of an unsaturated polyester resin, (b) 10 to 100 parts by weight of a glass flake having an average thickness of 0.5 to 5 microns and an average particle size of 100 to 400 microns, or 10 to 70 parts by weight of said glass flake and 10 to 150 parts of scaly metal pigment, (c) 0.1 to 1.0 part by weight of a ketone peroxide and (d) 0.5 to 2.0 parts by weight of a hydroperoxide and/or a peroxy ester. Also disclosed is a process for forming anti-corrosive coatings, which comprises spray-coating the above anti-corrosive coating composition to a thickness of 300 to 1500 microns by using a spray gun having a spray tip diameter of 0.5 to 3 mm.

Abstract: An anticorrosive coating process comprises:(i) a step of forming a primer coating layer by applying on a substrate an oil-type anticorrosive coating or an alkyd resin-type anticorrosive coating as a primer coating, followed by air-drying,(ii) a step of forming a binder coating layer by applying on the primer coating layer a phenol-modified alkyd resin-type coating containing a flaky pigment, followed by air-drying, and(iii) a step of forming a top coating layer by applying on the binder layer a top coating comprising (a) a fluorine-containing copolymer composed of from 40 to 60 molar % of a fluoroolefin, from 5 to 45 molar % of cyclohexylvinyl ether, from 5 to 45 molar % of an alkylvinyl ether, from 3 to 15 molar % of a hydroxyalkylvinyl ether and from 0 to 30 molar % of other comonomer and (b) a polyisocyanate, followed by air-drying.

Abstract: An anticorrosive coating process comprises:(i) a step of applying on a substrate a zinc-rich paint or an epoxy resin primer coating, followed by air-drying,(ii) a step of applying thereon an intermediate synthetic resin coating, followed by air-drying, and(iii) a step of applying thereon a top coating comprising (a) a fluorine-containing copolymer composed of from 40 to 60 molar % of a fluoroolefin, from 5 to 45 molar % of cyclohexylvinyl ether, from 5 to 45 molar % of an alkylvinyl ether, from 3 to 15 molar % of a hydroxyalkylvinyl ether and from 0 to 30 molar % of other comonomer and (b) a polyisocyanate, followed by air-drying.

Abstract: Disclosed is an anti-corrosive coating composition comprising (a) 100 parts by weight of an unsaturated polyester resin, (b) 10 to 100 parts by weight of a glass flake having an average thickness of 0.5 to 5 microns and an average particle size of 100 to 400 microns, or 10 to 70 parts by weight of said glass flake and 10 to 150 parts of scaly metal pigment, (c) 0.1 to 1.0 part by weight of a ketone peroxide and (d) 0.5 to 2.0 parts by weight of a hydroperoxide and/or a peroxy ester. Also disclosed is a process for forming anti-corrosive coatings, which comprises spray-coating the above anti-corrosive coating composition to a thickness of 300 to 1500 microns by using a spray gun having a spray tip diameter of 0.5 to 3 mm.

Abstract: This invention relates to a method for coating inner faces of metal pipes of a small diameter which comprises feeding a stream of a powdery resin at a rate of 2 to 10 m/sec into a metal pipe of a small diameter preheated at a temperature higher by 20.degree. to 70.degree.C. than the melting or softening point of said powdery resin so that the concentration of said powdery resin or a mixture of said powdery resin and a carrier is 5 to 40% by volume.