Abstract: A process is disclosed for manufacturing a circuit board having a metal layer in which a portion of the metal layer is removed by etching. A novel etch resist immersion tin composition is selectively applied to the metal layer to leave areas of coated and uncoated metal followed by etching the metal not coated with the resist. The immersion tin composition is applied as a substantially pore free coating at thicknesses of from about 0.08 to about 0.175 microns. The novel immersion tin composition contains a tin salt and both thiourea compounds and urea compounds.

Abstract: The invention relates to security fibers and other allied materials made luminescent by a dyeing process employing rare-earth compounds and their applications in fiduciary documents and other materials requiring authentication.

Abstract: An electroless copper plating bath having improved stability which contains a cationic polymer from acrylamide and/or methacrylamide. The plating bath also contains a cupric ion source, a reducing agent for the cupric ion source, and a complexing agent for the cupric ion.

Abstract: A novel stable, homogeneous aqueous solution for application to wood surfaces is provided herein. The aqueous solution consists essentially of creosote, a conventional inorganic wood preservative component, ammonia and an oil. The oil and the creosote are present in specified proportions in the aqueous solution. When the solution is applied to wood, and the wood dried, a creosote-treated wood surface which may be painted is provided.

Abstract: Rodent repellent paints and solid are disclosed which are comprised of thujone oil or cedar leaf oil in a suitable carrier such as lacquer, sodium silicate or paraffin.

Abstract: In accordance with the present invention, there can be provided a denture base for a dental prosthesis comprising a body having an inner surface to be in contact with patient's alveolus ridge; a lining layer covering the inner surface of the body; and an adhesive agent for bonding the lining layer to the inner surface of the body; wherein the body is made of polymethyl methacrylate; the lining layer is made of a rubber-like resilient material comprising an olefin thermoplastic elastomer; and the adhesive agent contains a copolymer comprising an olefin and methyl methacrylate. The denture base has an advantage that adhesive force between the lining layer and the body is strong, and the lining layer has suitable hardness for supporting the dental prosthesis.

Abstract: A marine anti-fouling paint capable of becoming smoother in use on a ship's hull moving through sea water comprises an effective amount of marine biocide and, as the film-forming binder, a polymer containing diorganotin moities linked to the polymer by carboxylate linkages. The binder is preferably a copolymer of units of a diorganotin salt of an olefinically unsaturated carboxylic acid of the formula: ##STR1## where R' is an olefinically unsaturated group, each group R is a monovalent organic radical linked to the tin atom by a carbon-tin bond and X represents an electronegative group linked to the tin atom by an atom other than carbon, together with units of at least one olefinically unsaturated comonomer.

Abstract: A dental cement composition consisting of a composition A and a composition B,said composition A comprising (a) 100 parts by weight of a powder containing 20 to 70% by weight of calcium oxide and 30 to less than 80% by weight of aluminum oxide, said powder being coated on the surface with a water-soluble high-molecular substance, and (b) 2 to 70 parts by weight of a calcium hydroxide powder, andsaid composition B comprising an aqueous solution containing 0.01 to 70% by weight of a water-soluble high-molecular substance.

Abstract: A catalytic adsorbate suspended in an aqueous solution comprising reduced catalytic metal on an organic suspending agent where the reduced catalytic metal has a maximum dimension not exceeding 500 angstroms and the organic suspending agent is one capable of complexing with ions of the catalytic metal. The catalytic adsorbate is useful for the electroless metal deposition of substrates that are non-catalytic to electroless metal deposition.

Abstract: Composite articles and cutting tools are prepared by densification to form a body consisting essentially of particles of hard refractory boride uniformly distributed in a silicon nitride matrix consisting essentially of a first phase and a second phase. The first phase consists essentially of crystalline silicon nitride and the second phase is an intergranular refractory phase comprising silicon nitride and a suitable densification aid selected from the group consisting of yttrium oxide, cerium oxide, zirconium oxide, hafnium oxide and the lanthanide rare earth oxides and mixture thereof. The resulting composite article or cutting tool has a fracture toughness equal to or greater than about 4 MN/m.sup.3/2.

Abstract: A stable thixotropic coating composition especially suitable for dipspin application having an aqueous acid binder solution which comprises phosphate ions and ions of the group of chromate ions or molybdate ions, and a dispersible hydrated alumina having a boehmite type crystal lattice.

Abstract: A process for beneficiating a crude kaolinitic clay mineral to produce a clay filler for use in papermaking to improve the brightness, the color characteristics and the light scattering efficiency of the paper product. The crude kaolin clay is blunged with water containing a dispersing agent consisting of a blend of from about 20% to about 50% by weight of a water-soluble carbonate, about 20% to about 50% by weight of a water-soluble polyacrylate, and from 0% to about 60% by weight of a water-soluble anionic phosphate, to form a high solids fluid aqueous clay suspension having an acidic pH. This clay suspension is then fractionated to reduce the percentage of particles therein larger than 45 microns to not more than 0.2% by weight. The fractionated clay suspension is treated with an alkaline leaching solution containing a reducing agent effective in converting ferric ions to ferrous ions.

Abstract: The invention is a method for sizing polytetrafluoroethylene fabrics comprising:(a) forming a sizing composition of a perfluorinated polymer containing sites convertible to ion exchange groups and a treating agent having: a boiling point less than about 110.degree. C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.2 hildebrands;(b) contacting the sizing composition with the fibers of a polytetrafluoroethylene fabric; and(c) removing the treating agent from the sizing composition.Particularly preferred as a treating agent is a compound represented by the general formula:XCF.sub.2 --CYZX'wherein:X is selected from the group consisting of F, Cl, Br, and I;X' is selected from the group consisting of Cl, Br, and I;Y and Z are independently selected from the group consisting of H, F, Cl, Br, I and R';R' is selected from the group of perfluoroalkyl radicals and chloroperfluoroalkyl radicals having from 1 to 6 carbon atoms.

Abstract: There is provided a method for indirect bonding of chemically or light curable resin based restoratives especially acrylates and methacrylates, to the metal base of dental cast restorations. The invention is particularly useful in cases of in situ repairs of damaged or worn porcelain or polymeric veneers on cast restorations made of precious and non-precious metals. According to the invention, the exposed metal of the restoration is covered with a layer of primer consisting essentially of a copolymer of polymethacrylic or polyacrylic acid followed by the application of the polymerizable restorative material.

Abstract: This invention relates to two-pack type dental lining compositions comprising (a) a solution of a polymer having at least 10 mole % of a carboxyl-containing vinyl monomer, and (b) a solution of a zirconium chelate compound represented by the following general formula ##STR1## (wherein R.sub.1 denotes --CH.sub.3, --OCH.sub.3 or --OCH.sub.2 CH.sub.3, R.sub.2 stands for an alkoxy of 2 to 10 carbon atoms, and n is an integer from 2 to 4).

Abstract: A dental impression composition is provided which has high tensile and gel strengths, but an absence of graininess through the use of zinc borate and a water soluble alkylene glycol in the composition.

Abstract: There is provided an aqueous emulsion of (a) a hydrolyzable silane having the general formula:R.sub.n --Si--(R').sub.4-nwherein R is a hydrocarbyl group containing from 1 to 20 carbon atoms, R' is a hydrolyzable group and n is 1 or 2, and oligomers thereof, e.g., dimers and trimers, and other oligomers, (b) an emulsifying agent having an HLB value of from 4 to 15, and (c) water.

Abstract: A dental cement composition consisting of a composition A and a composition B,said composition A comprising at least two powders, (a) 100 parts by weight of a powder containing more than 20% by weight to 70% by weight of calcium oxide and 30% by weight to less than 80% by weight of aluminium oxide and treated on the surface with 0.01 to 5% by weight of at least one selected from the group consisting organic acids and/or inorganic acids, and (b) 2 to 70 parts by weight of a calcium hydroxide powder, andsaid composition B comprising of an aqueous solution containing 0.01 to 70% by weight of a water-soluble high-molecular substance.

Abstract: A corrosion-inhibiting coating composition for application onto rusted steel or iron surfaces is disclosed. The coating composition comprises an organic silicate, citric acid, and a non-aqueous solvent. The organic silicate is preferably present in an amount sufficient to provide about 12% to 24% silicon dioxide in the cured coating from the composition and is preferably pre-hydrolyzed in an amount of about 70% to 90%. Citric acid is preferably present in an amount of about 0.1 to 0.2 grams per cubic centimeter of the coating composition. Dissolution and complexation of the rust by the citric acid provides a pigment which causes the organic silicate to become a film-forming binder. Zinc chloride is preferably added to the composition to increase the rate of rust dissolution and to improve binder properties.

Abstract: A zinc-based composition comprising, by weight:from about 0.1 to 4 percent copper;from about 0.1 to about 1 percent nickel;from about 0.01 to less than 0.5 percent aluminum;0 to about 0.5 percent chromium;0 to about 0.5 percent titanium; and the remainder being zinc is provided. The composition is useful for coating or joining metal surfaces, particularly metals formed of or containing copper.The above composition may be used with or without a flux. Particularly beneficial results are obtained when a flux having a composition comprising, by weight:from about 5 to about 70 percent ZnCl.sub.2 ;from about 1 to about 28 percent NH.sub.4 Cl;from about 0.1 to about 10 percent SnCl.sub.2 ;from about 0 to about 10 percent HCl;from about 0 to about 10 percent Li.sub.2 B.sub.4 O.sub.7 ;from about 0 to about 5 percent MgBr.sub.2 ;from about 0 to about 5 percent ZnBr.sub.2 ; and about 0 to about 94 percent water is used.