Abstract: The invention is directed to a method and composition for providing roughened copper surfaces suitable for subsequent multilayer lamination. A smooth copper surface is contacted with an adhesion promoting composition under conditions effective to provide a roughened copper surface, the adhesion promoting composition consisting essentially of an oxidizer, a pH adjuster, a topography modifier, and a uniformity enhancer. A coating promoter may be used in place of the uniformity enhancer or in addition to the uniformity enhancer. The adhesion promoting composition does not require a surfactant. The process may further comprise the step of contacting the uniform roughened copper surface with a post-dip, wherein the post-dip comprises an azole or silane compound or a combination of said azole and said silane. The post-dip may further comprise, alone or in combination, a titanate, zirconate, and an aluminate. The pH adjuster is preferably sulfuric acid and the oxidizer is preferably hydrogen peroxide.

Abstract: A corrosive composition, such as an alkaline aqueous carbon dispersion, a cleaner, a cleaner conditioner, or a conditioner, comprises a corrosion inhibitor, e.g., benzotriazole. The corrosion inhibitor is present in an amount effective to reduce or stop the dissolution of metal from a metallic surface, such as a printed circuit board, in contact with the composition. A method to reduce or stop the dissolution of metal from a metallic surface in contact with a corrosive composition, and a method to stabilize or recover a corrosive composition containing metal contaminants by adding an effective amount of a corrosion inhibitor to the corrosive composition.

Abstract: A printed wiring board comprising conductive layers separated by nonconductive material and having through holes or other nonconductive surfaces on which an electrically conductive carbon coating is formed. The conductive carbon coating includes electrically conductive carbon having a mean particle size not greater than about 1 micron and a water-dispersible organic binding agent. The conductive carbon coating formed on the nonconductive surfaces has a low electrical resistance and is tenacious enough to be plated and exposed to molten solder without creating voids or losing adhesion.

Abstract: The invention is directed to a method and composition for providing roughened copper surfaces suitable for subsequent multilayer lamination. A smooth copper surface is contacted with an adhesion promoting composition under conditions effective to provide a roughened copper surface, the adhesion promoting composition consisting essentially of an oxidizer, a pH adjuster, a topography modifier, and a uniformity enhancer. A coating promoter may be used in place of the uniformity enhancer or in addition to the uniformity enhancer. The adhesion promoting composition does not require a surfactant. The process may further comprise the step of contacting the uniform roughened copper surface with a post-dip, wherein the post-dip comprises an azole or silane compound or a combination of said azole and said silane. The post-dip may further comprise, alone or in combination, a titanate, zirconate, and an aluminate. The pH adjuster is preferably sulfuric acid and the oxidizer is preferably hydrogen peroxide.

Abstract: The invention is directed to a method and composition for providing chemically-resistant roughened copper surfaces suitable for subsequent multilayer lamination. In one embodiment, a smooth copper surface is contacted with an adhesion promoting composition under conditions effective to provide a roughened copper surface, the adhesion promoting composition comprising an oxidizer, a pH adjuster, a topography modifier, and a sulfur-containing coating stabilizer. In another embodiment, a smooth copper surface is contacted with an adhesion promoting composition under conditions effective to provide a roughened copper surface, the adhesion promoting composition comprising an oxidizer, a pH adjuster, and a topography modifier. Then, in a subsequent step, the roughened copper surface is contacted with an acid resistance promoting composition.

Abstract: The invention is directed to a method and composition for providing chemically-resistant roughened copper surfaces suitable for subsequent multilayer lamination. In one embodiment, a smooth copper surface is contacted with an adhesion promoting composition under conditions effective to provide a roughened copper surface, the adhesion promoting composition comprising an oxidizer, a pH adjuster, a topography modifier, and a sulfur-containing coating stabilizer. In another embodiment, a smooth copper surface is contacted with an adhesion promoting composition under conditions effective to provide a roughened copper surface, the adhesion promoting composition comprising an oxidizer, a pH adjuster, and a topography modifier. Then, in a subsequent step, the roughened copper surface is contacted with an acid resistance promoting composition.

Abstract: The invention is directed to a method and composition for providing chemically-resistant roughened copper surfaces suitable for subsequent multilayer lamination. In one embodiment, a smooth copper surface is contacted with an adhesion promoting composition under conditions effective to provide a roughened copper surface, the adhesion promoting composition comprising an oxidizer, a pH adjuster, a topography modifier, and a sulfur-containing coating stabilizer. In another embodiment, a smooth copper surface is contacted with an adhesion promoting composition under conditions effective to provide a roughened copper surface, the adhesion promoting composition comprising an oxidizer, a pH adjuster, and a topography modifier. Then, in a subsequent step, the roughened copper surface is contacted with an acid resistance promoting composition.

Abstract: A method of applying a conductive carbon coating to a non-conductive surface and a printed wiring board having through holes or other nonconductive surfaces treated with such carbon coatings are disclosed. A conditioning agent is applied to the non-conductive surface to form a conditioned surface. A liquid dispersion of electrically conductive carbon (for example, graphite) having a mean particle size no greater than about 50 microns, combined with an organic binding agent, is coated on the conditioned surface to form an electrically conductive carbon coating. The conductive carbon coating is then optionally fixed on the (formerly) nonconductive surface and dried. The resulting coating has a low electrical resistance and is tenacious enough to be plated and exposed to molten solder without creating voids or losing adhesion, yet is easily removable from copper surfaces of the substrate by microetching.

Abstract: A composition and method for cleaning and conditioning a non-conductive surface defined by a through hole in a printed circuit board (PCB) is disclosed. The through hole surface is contacted with the composition of the invention to provide a cleaned and conditioned surface. The clean and conditioned surface is coated with conductive carbon particles (usually graphite) to provide a carbon-coated surface. The carbon-coated surface is electro plated and then soldered using hot solder. Those surfaces that have been soldered and also treated with the composition of the invention exhibit fewer blow hole problems. The composition of the invention comprises carbonates, binders, and resins, and combinations thereof, that improve the adhesion and coverage of a coating containing graphite to a surface defined by a through hole bore or other substrate. (“Through holes” as used herein refers both to through holes and to vias.

Abstract: A method for preventing a carbon dispersion from increasing in viscosity during use is described. The dispersion comprises graphite particles or carbon black particles or a combination of both dispersed in a fluid. The method involves lowering the susceptibility of the carbon dispersion to an increase in viscosity or ionic strength by lowering its pH or reducing its exposure to reactive components in the ambient atmospheric gas. The pH can be lowered by at least partially removing ammonia from the dispersion, or by adding a material that reduces the pH of the dispersion. The stability of the dispersion can also be improved by isolating the dispersion from reactive atmospheric gas. The stabilized aqueous carbon dispersion can have a viscosity of less than about 20 cps and a conductivity of less than about 3 mS.

Abstract: A desmear process for removing resin smeared on an interior wall of a through hole drilled in a resinous substrate, especially resinous substrates made from epoxy, polyimide, cyanate ester resins or bis-maleimide triazine epoxy resins. The process involves contacting the resin smear with a mixture of gamma-butyrolactone and water to soften the resin smear, followed by treatment with an alkaline permanganate solution to remove the softened resin, and treatment with an aqueous acidic neutralizer to neutralize and remove the permanganate residues. The gamma-butyrolactone is effective as a single solvent for softening and swelling resin smears from substrates made from epoxy, polyimide, cyanate ester resins, bis-maleimide triazine epoxy resins, and polyimide resins.

Abstract: A composition and method for applying an electrically conductive coating to an initially electrically nonconductive surface, such as a printed wiring board having through holes is disclosed. The method is carried out by applying a composition of electrically conductive carbon particles, a second conductive material, a water dispersible binding agent, and an aqueous dispersing medium to a nonconductive substrate to form a substantially continuous, electrically conductive coating. Enough of the carbon particles are present to provide an electrically conductive coating when the composition is applied to the substrate. Enough of the second conductive material is present to provide an improved electrically conductive coating when the composition is applied to the substrate. The resulting coating carbon coating has an improved conductivity over prior through hole coating compositions and processes and is capable of being exposed to molten solder without resulting in the formation of blowholes.

Abstract: A silane coating (32) is provided which affords non-stick properties to a metal surface (20, 22) of a cooking utensil (10) and which can be provided with colorant (42) to impart a stable color appearance, including white, to the utensil (10). An easy repair method is also described.

Abstract: A composition and method for cleaning and conditioning a non-conductive surface defined by a through hole in a printed circuit board (PCB) is disclosed. The through hole surface is contacted with the composition of the invention to provide a cleaned and conditioned surface. The clean and conditioned surface is coated with conductive carbon particles (usually graphite) to provide a carbon-coated surface. The carbon-coated surface is electro plated and then soldered using hot solder. Those surfaces that have been soldered and also treated with the composition of the invention exhibit fewer blow hole problems. The composition of the invention comprises a cationic conditioning agent and one of a binder or an anionic dispersant that improve the adhesion and coverage of a coating containing graphite to a surface defined by a through hole bore or other substrate. (“Through holes” as used herein refers both to through holes and to vias.

Abstract: A method of applying a conductive carbon coating to a nonconductive surface, conductive carbon compositions for that purpose, and a printed wiring board having through holes or other nonconductive surfaces treated with such carbon compositions are disclosed. A conditioning agent, made (for example) by condensing a polyamide and epichlorohydrin, is applied to the nonconductive surface to form a conditioned surface. A liquid dispersion of electrically conductive carbon (for example, graphite) having a mean particle size no greater than about 50 microns is coated on the conditioned surface to form an electrically conductive carbon coating. The conductive carbon coating is then optionally fixed on the (formerly) nonconductive surface. Fixing may be accomplished, for example, by applying a fixing liquid such as a dilute aqueous acid to the carbon-coated surface. The coating is then dried.

Abstract: A method of applying a conductive carbon coating to a non-conductive surface, conductive carbon compositions for that purpose, and a printed wiring board having through holes or other nonconductive surfaces treated with such carbon compositions are disclosed. A liquid dispersion of electrically conductive carbon (for example, graphite) having a mean particle size no greater than about 50 microns is coated on the non-conductive surface to form an electrically conductive carbon coating. The conductive carbon coating is then fixed on the (formerly) nonconductive surface. Fixing may be accomplished in a variety of different ways. For example, the fixing step can be carried out by applying a fixing liquid to the carbon-coated surface. One example of a suitable fixing liquid is a dilute aqueous acid. Fixing may also be carried out by removing the excess carbon dispersion with an air knife or other source of compressed air.

Abstract: A method for treating a non-conductive through hole surface of a printed wiring board is disclosed. A printed wiring board including through holes is cleaned, conditioned, and a conductive coating is applied to the initially-nonconductive through hole by contacting it with a series of baths. The conductive coating, for example a graphite dispersion coating, facilitates later electroplating of the conductive surface. While at least partially immersing the through hole in one or more of these baths, ultrasonic energy is introduced in the bath in the vicinity of the through hole. The ultrasonic energy can be introduced during the entire immersing step, before the immersing step, or both. The ultrasonic energy reduces the formation of blowholes during later processing (and especially soldering) of the printed wiring board.

Abstract: An improved desmear process for removing resin smeared on an interior wall of a through hole drilled in a resinous substrate, especially resinous substrates made from epoxy, polyimide, cyanate ester resins and bis-maleimide triazine epoxy resins. The process involves contacting the resin smear with a solvent solution to soften the resin smear, followed by treatment with an alkaline permanganate solution to remove the softened resin, and treatment with a neutralizer to neutralize and remove the permanganate residues. The solvent solution comprises a mixture of at least two solvent components, with at least one solvent component being selected from the group consisting of gamma-butyrolactone, ethyl-3-ethoxypropionate, N-ethyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N-(2-hydroxyethyl)-2-pyrrolidone, and N-octyl-2-pyrrolidone. The solvent solution is selective for the softening and removal of epoxy, polyimide, cyanate ester resins and bis-maleimide triazine epoxy resins.

Abstract: A method of applying a conductive carbon coating to a non-conductive layer, conductive carbon compositions, and a printed wiring board having through holes or other surfaces treated with such carbon compositions are disclosed. A board or other substrate including at least first and second electrically conductive metal layers separated by a non-conductive layer is provided. The board has a recess extending through at least one of the metal layers into the non-conductive layer. The recess has a non-conductive surface which is desired to be made electrically conductive. The carbon in the dispersion has a mean particle size no greater than about 50 microns. The method is carried out by applying the carbon dispersion to a non-conductive surface of the recess to form a substantially continuous, electrically conductive carbon coating. Optionally, the coating is then fixed, leaving the carbon deposit as a substantially continuous, electrically conductive layer. Chemical and physical fixing steps are disclosed.

Abstract: A method of applying a conductive carbon coating to a non-conductive layer, conductive carbon compositions, and a printed wiring board having through holes or other surfaces treated with such carbon compositions are disclosed. A board or other substrate including at least first and second electrically conductive metal layers separated by a non-conductive layer is provided. The board has a recess extending through at least one of the metal layers into the non-conductive layer. The recess has a non-conductive surface which is desired to be made electrically conductive. The carbon in the dispersion has a mean particle size no greater than about 50 microns. The method is carried out by applying the carbon dispersion to a non-conductive surface of the recess to form a substantially continuous, electrically conductive carbon coating. Optionally, the coating is then fixed, leaving the carbon deposit as a substantially continuous, electrically conductive layer. Chemical and physical fixing steps are disclosed.