Abstract: Aqueous solutions of amide polymers such as polyacrylamide when treated with small amounts of a water-soluble polyaldehyde at an alkaline pH react to form film gels within a short time at ambient temperature. Such gels are usefully employed to plug porous subterranean formations, for grouting of leaking soil pipes or wells, and to otherwise render porous structures impermeable to the passage of liquids such as water.

Abstract: Plates made of porous material are strengthened by impregnation with a hardening fluid. The plates are stacked, subjected to vacuum in a chamber and immersed in the treating fluid, and pressure is then exerted on the fluid. The apparatus includes a chamber which contains a body of the fluid and which can be made airtight by applying a cover. The cover carries a support frame which carries a stack of plates, the cover having a hoisting device to lower the frame and stack into the fluid. A vacuum source and pressure source are connected to the container through a control valve.

Abstract: A compound body comprising a metallic basic body, an inner layer or layers of carbides and/or nitrides of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Si, or B, and an outer layer or layers of a mixture of oxides and nitrides and/or oxynitrides of Cr, Al, Ca, Mg, Th, Sc, Y, La, Ti, Hf, V, Nb, or Ta. The compound body can be used as a part subject to wear, and for machining metallic materials.

Abstract: A heat-sensitive recording sheet comprising a support and a recording layer containing an electron donating colorless dye and a compound represented by the following formula: ##STR1## wherein R represents an alkyl group containing 2 to 12 carbon atoms.

Abstract: A multiple-layer process for applying, in alternate, successive layers, the protein, avidin, and a biotin-containing extender material to a solid surface to modify the properties of the surface and to the multiple-layer product so prepared.

Abstract: In order to produce hard solderable metal coatings on a ceramic there is applied to the ceramic base a thin layer of a palladium alloy containing 20-70% of cobalt and/or iron. The coating is preferably applied by vapor deposition or sputtering. The adhesiveness of the coatings is still further improved if there is added to the alloy 3-20% of chromium, manganese and/or titanium.

Abstract: The outer surface layers of a flexible polyetherurethane foam are impregnated and dried with a latex of a flexible carboxylated styrene-butadiene type copolymer to provide a polyurethane foam having a surface which resists degradation in contact with a hot metal, e.g., steel, surface.

Abstract: An apparatus and method are provided for depositing submicron patterns on a substrate. The apparatus includes an evaporative source located opposite the substrate so that molecules from the source can be deposited directly on the substrate. A mask is located between the evaporative source and the substrate, the mask having openings which correspond to the desired pattern to be deposited on the substrate. A plate is located between the mask and the substrate, the plate having an aperture for allowing evaporated molecules to be deposited on the substrate according to the pattern of the mask.

Abstract: A method is disclosed for reducing the reactivity of a glass surface by blocking reactive sites such as silanol groups at the glass surface with a molecular layer of fluorocarbon. The method involves adsorbing multivalent metal cations at the glass surface to provide anchoring sites for the chemisorption of otherwise nonreactive fluorocarbons.

Abstract: A conductive video disc replica is cleaned by washing with an aqueous solution comprising an oxidizing agent, a base and a surfactant of a fluorocarbon added in an amount so that the solution has a surface energy of about 35 dynes/cm.sup.2 or less. This solution removes metallic and oxygen-containing impurities from the surface of the disc and leaves a fluorinated surface.

Abstract: Shaped articles of polyvinyl chloride resins containing low-molecular plasticizers are irradiated with ultraviolet light of a wavelength in the vacuum ultraviolet region to cause the shaped articles to form therein a cross linked layer capable of preventing otherwise possible exudation of plasticizers to their surface.

Abstract: A surface of a substrate 11 (FIG. 2) is uniformly coated with a liquid L by wetting the surface with the liquid and compressibly contacting the wetted surface with an applicator member 10 having an outer layer 14 of a compressible liquid absorbing material with inverse sponge characteristics and an inner layer 13 of compliant material. Preferably the member is a roller 10 having a silicone rubber or polyurethane inner layer and a chamois outer layer. A plurality of the rollers 10 are arranged to be in compressive contact with the surfaces of a plurality of substrates 11 as the substrates are being removed from the liquid L (arrow A), the movement of the substrates 11 causing rotation (arrow F) of the rollers to apply a uniform coating of the liquid on the contacted surfaces.

Abstract: The invention relates to a low-viscosity, solvent-free epoxy-based coating composition consisting essentially of:(a) an epoxy fraction consisting of polyphenol epoxy resins and mixtures thereof; and(b) a curing fraction consisting essentially of:(1) a non-volatile, aromatic extender selected from the group consisting of coal tar, distillates of coke and petroleum with boiling points above about 200.degree. C., and mixtures thereof;(2) an amine curing agent having a molecular weight of about 200-600 selected from the group consisting of:(i) cycloaliphatic diamines having a single amine group directly attached to a single ring structure and the other amine group directly attached to a carbon atom in an aliphatic chain or to a second ring structure;(ii) polyamines having polyaliphatic oxide back-bones; and,(iii) mixtures thereof; and,(3) a curing accelerator selected from the group consisting of tertiary amines.

Abstract: The present invention relates to a process for forming a multi-layer coating including at least two coating layers by performing the oven drying step at one time, which comprises coating at least partially the surface of the substrate with a powder coating composition, then applying a slurry paint composition comprising synthetic resin particles dispersed in an aqueous medium and then heating.

Abstract: Disclosed is a technique for providing a protective oxide layer on an alloy. The technique involves the preliminary cleaning of the alloy's surfaces to remove as much unwanted oxide as possible and the subsequent exposure of the alloy surface to an environment which produces an acid resistant oxide by selective oxidation of one of the constituents of the alloy and which acts as a reducing environment for other constituents of the alloy. For the production of a chromium oxide layer on a stainless steel comprising chromium, iron, and nickel, a suitable environment includes a 600.degree.-1200.degree. C. mixture of H.sub.2 and H.sub.2 O. If a major portion of the mixture is H.sub.2, the chromium is oxidized whereas the iron and nickel are not.

Abstract: Crushed foam coated urethane foam is disclosed wherein the crushed foam coating contains a pigment or a flame retardant or both to protect the urethane foam against discoloration due to ultraviolet light or to provide protection against fires. The crushed foam may be obtained from a frothed latex applied to the polyurethane foam, dried and crushed to a final thickness of 10 mils to 250 mils.

Abstract: An electrographic recording material comprising a conductive sheet support coated with an electrically insulating layer comprising an intimate blend of a polymeric binder and up to 500 parts of an inert finely divided pigment per 100 parts by weight of polymeric binder. The binder comprises from about 40 to about 90 parts by weight of a poly(vinyl acetal) and from about 10 to about 60 parts by weight of a polystyrene or a poly(.alpha.-methylstyrene). The electrographic recording material exhibits improved toner adhesion.

Abstract: The disclosed coating system comprises a curable liquid epoxide and an amine hardener or co-curative. The amine co-curative comprises a blend of an aliphatic amine (e.g. trimethyl hexamethylene diamine) and a bismethylamino aromatic compound (e.g. a xylylene diamine). This coating system, when suitably combined with a reflectorizing material, has the ability to satisfy some or all of the very troublesome requirements of a highway marking or striping composition and is therefore useful in methods for marking or striping paved surfaces.

Abstract: A method is described for increasing the impact properties of dense silicon nitride articles. The method includes the application of a slurry composed predominately of silicon powder to the surface of the dense silicon nitride article. The slurry coated article is then nitrided at an elevated temperature to partially convert the silicon powder to silicon nitride and to bond the particles together and to the substrate. About 15 to 45 volume percent of the silicon powder is not converted to silicon nitride but remains as elemental silicon.

Abstract: An aluminum coated carbon article or composite, and process therefor having aluminum chemically bonded to carbon via an interface of a metal monocarbide formed in situ when an intermetallic phase comprising aluminum and a metal capable of reacting with carbon to form a metal carbide is reduced by carbon to aluminum and a metal carbide, the metal selected from the group consisting of tantalum, titanium and hafnium.