摘要:
Aqueous acidic coating solutions are described for treating zinc or zinc alloy surfaces comprising trivalent chromium as substantially the only chromium ion present, fluoride ion, an acid other than nitric acid, and an oxidizing agent. The coating solutions containing trivalent chromium as substantially the only chromium ion present preferably are prepared by reducing an aqueous solution of hexavalent chromium with sufficient reducing agent to reduce all of the hexavalent chromium to trivalent chromium. Chromate coatings on zinc and zinc alloy surfaces are produced by contacting said surfaces with an aqueous acidic solution of the invention.
摘要:
An electroplating bath and a process for electrodepositing a crystalline chromium deposit on a substrate, in which the electroplating bath comprising trivalent chromium and a source of divalent sulfur, and substantially free of hexavalent chromium; immersing a substrate in the electroplating bath; and applying an electrical current to deposit a crystalline chromium deposit on the substrate, wherein the chromium deposit is crystalline as deposited, and/or has a lattice parameter of 2.8895+/−0.0025 Å, and/or the crystalline chromium deposit has a {111} preferred orientation.
摘要:
The present invention relates to a process for treating a metal substrate to improve adhesion of polymeric materials thereto, comprising the steps of intergranular etching a surface of the metal substrate; and applying an immersion plated metal to the intergranular etched surface by immersing the surface in an immersion plating composition comprising one or more plating metals selected from tin, silver, bismuth, copper, nickel, lead, zinc, indium, palladium, platinum, gold, cadmium, ruthenium, cobalt, gallium and germanium. In one embodiment, the immersion plated metal is tin. In one embodiment, the process further comprises a step of adhering the immersion metal plated surface to a surface of a polymeric non-conductive material. In another embodiment, the polymeric nonconductive material is one or more of PTFE, an epoxy resin, a polyimide, a polycyanate ester, a butadiene terephthalate resin, or mixtures thereof. In one embodiment, the process further comprises a step of applying a silane over the immersion plated metal from an aqueous solution of a silane.
摘要:
A method is described for preparing a black chromium-containing conversion coating on a zinc-nickel alloy surface containing at least about 8% nickel in the alloy or on a zinc-iron alloy surface. The method of the invention comprises contacting said surfaces with an aqueous acidic solution comprising trivalent chromium and an amount of a phosphorus acid selected from phosphoric acid, phosphorous acid, hypophosphorous acid, and mixtures thereof effective to provide a solution having a pH of from about 1.0 to about 2.5. Metal articles having zinc-nickel alloy surfaces containing at least about 8 % nickel in the alloy or having zinc-iron alloy surfaces which have been treated in accordance with the method of the invention exhibit the desired blackened surfaces and are characterized by improved corrosion resistance.
摘要:
A coated substrate and a process for forming the coated substrate, including a first lubricious coating layer overlying the substrate, the first lubricious coating layer including a first lubricant providing to the first lubricious coating layer a first coefficient of friction; and a second lubricious coating layer overlying the first lubricious coating layer, the second lubricious coating layer including a second lubricant providing to the second lubricious coating layer a second coefficient of friction, in which the second coefficient of friction is greater than the first coefficient of friction.
摘要:
Silane compositions are described which comprise (A) a silane coupling agent; and (B) a tris(silylorgano)amine or alkane characterized by the formulae [(RO)3SiR1]3N (I) or [(RO)3SiR1]3CR2 (II) wherein each R is independently an alkyl, alkoxyalkyl, aryl, aralkyl or cycloalkyl group of less than 20 carbon atoms; R1 is a divalent hydrocarbon or polyether group of less than 20 carbon atoms; and R2 is a functional group represented by CnH2nX wherein n is from 0 to 20 and X is selected from the group consisting of amino, amido, hydroxy, alkoxy, halo, mercapto, carboxy, acyl, vinyl, allyl, styryl, epoxy, isocyanato, glycidoxy, and acryloxy groups. The silane compositions of the present invention are adhesive compositions providing improved bonding of surfaces such as glass, metal and metal oxides to thermosetting resins. The silane compositions also exhibit improved moisture resistance. The silane compositions are particularly useful as adhesives in preparing multi-layer laminates such as printed circuit boards.
摘要:
A method is described for producing an iridescent chromium coating on a zinc-nickel alloy surface containing at least about 8% nickel in the alloy. The method of the invention comprises(A) contacting said surface with an aqueous acidic solution maintained at a temperature of from about 38.degree. C. to about 75.degree. C., wherein the solution comprises trivalent chromium as substantially the only chromium ion present, and a phosphorus acid selected from phosphoric acid, phosphorous acid, hypophosphorous acid and mixtures thereof in an amount effective to provide a solution having a pH of from about 1.0 to about 2.5; and(B) drying the surface.Metal articles having zinc-nickel alloy surfaces containing at least about 8% nickel in the alloy which have been treated in accordance with the method of the invention exhibit the desired iridescent coating and are characterized by improved corrosion resistance.
摘要:
This invention relates to a paste composition, comprising:(A) at least 12% by weight of a paste forming compound and(B) at least one oxidizing agent which is a metal oxide or salt;(C) at least one reducing metal wherein (B) and (C) are capable of forming a metal coating;(D) at least one nonreactive, powder material capable of being incorporated into the coating formed from (B) and (C) wherein the material is selected from the group consisting of a metal, a metal alloy and a polymer; or(E) mixture of two or more thereof.The paste compositions control the pyrophoricity and explosive tendencies of the metal powders used in the process. Further, the paste affords easy handling of the materials. Delivery of the paste may be manual or automatic such as with a grease pump.The mechanical plating compositions of the present invention may also include (D) a nonreactive, powder material capable of being incorporated into a coating wherein the material is selected from the group consisting of a metal, a metal alloy and a polymer.
摘要:
A crystalline chromium deposit having a lattice parameter of 2.8895+/−0.0025 Å, and an article including the crystalline chromium deposit. An article including a crystalline chromium deposit, wherein the crystalline chromium deposit has a {111} preferred orientation. A process for electrodepositing a crystalline chromium deposit on a substrate, including providing an electroplating bath comprising trivalent chromium and a source of divalent sulfur, and substantially free of hexavalent chromium; immersing a substrate in the electroplating bath; and applying an electrical current to deposit a crystalline chromium deposit on the substrate, wherein the chromium deposit is crystalline as deposited.
摘要:
A printed circuit board including electrical circuitry formed on an outer surface of the printed circuit board, the circuitry comprising copper or a copper alloy; a final finish on the circuitry, the final finish including a coating of tin on the copper or copper alloy circuitry; and an alloy cap layer on the tin coating, the alloy cap layer comprising at least two immersion-platable metals. The immersion platable metals in the alloy cap layer may be at least two metals selected from tin, silver, bismuth, copper, nickel, lead, zinc, indium, palladium, platinum, gold, cadmium, ruthenium and cobalt. The circuitry remains whisker free and solderable.