Abstract: A method for the preparation a photo-mask used for photo-imaging selected areas on the surfaces of a three-dimensional printed circuit board substrate. The photo-mask comprises a membrane transparent and degradation resistant to UV light, having at least one side with a contoured shape conforming, and flexible enough to comply with surface irregularities on the surfaces of the three-dimensional substrate being photo-imaged. A pattern of tracks opaque to UV light is positioned along the contoured shape of the membrane. The pattern of tracks on the photo-mask is in accordance with a desired conductive metal trace pattern on the surfaces of the three-dimensional printed circuit board substrate. The photo-mask is prepared by dispensing a track material in a boustrophedenous manner on the surfaces of the substrate being photo-imaged. A membrane material is then poured upon the surfaces containing the dispensed tracks.

Abstract: A method for the preparation a photo-mask used for photo-imaging selected areas on the surfaces of a three-dimensional printed circuit board substrate. The photo-mask comprises a membrane transparent and degradation resistant to UV light, having at least one side with a contoured shape conforming, and flexible enough to comply with surface irregularities on the surfaces of the three-dimensional substrate being photo-imaged. A pattern of tracks opaque to UV light is posiitoned along the contoured shape of the membrane. The pattern of tracks on the photo-mask is in accordance with a desired conductive metal trace pattern on the surfaces of the three-dimensional printed circuit board substrate. The photo-mask is prepared by photo-imaging and then depositing a track material on a film that conformed to the surfaces of the three-dimensional substrate. An adhesive layer applied over the film cements a membrane material poured upon the adhesive layer.

Abstract: The method is provided for treating the surface of a polyetherimide substrate to improve its adhesion characteristics for electrolessly deposited metal, such as copper. There is employed a series of surface treatments including the initial immersion of the polyetherimide substrate in sulfuric acid, contact with aqueous base, such as potassium hydroxide, followed by oxidation with an alkali metal permanganate such as potassium permanganate, and surface treatment with a reducing agent, such as a hydroxylamine salt. Polyetherimide metal composites are also provided.

Abstract: A polyimide surface is pretreated in preparation for an adhesion promotion treatment and subsequent metallization on the surface, wherein the pretreatment comprises the steps of:(A) contacting the polyimide surface with an aqueous solution of nitric acid having a concentration of about 35 to about 70% by weight or an aqueous solution of hydrochloric acid having a concentration of about 10 to about 38% by weight;(B) rinsing the acid-treated polyimide surface with water so as to substantially remove the acid from the surface of the polyimide;(C) contacting the rinsed polyimide surface with a mild etching agent, resulting in the formation of a residual film on the polyimide surface;(D) contacting the etched polyimide surface with a basic solution, and(E) removing the residual film formed on the surface of the polyimide after contact with the mild etching agent in step (C).

Abstract: A method for removing residual precious metal catalyst from a plastic, metal-plated surface is disclosed. The method involves the oxidation of the precious metal without degrading the plated metal or the plastic, followed by washing away the oxidized precious metal. This invention further includes methods for the plating of metal directly on the surface of a plastic substrate.

Abstract: An improved method for pretreating a polyimide surface in preparation for an adhesion promotion treatment and subsequent metallization is disclosed, wherein the pretreatment comprises mild etching of the surface, contact of the surface with a basic solution, and contact of the surface with a cationic surfactant which is capable of removing a residual film formed on the surface after the mild etching step. This invention further includes articles such as printed circuit boards, which comprise a polyimide substrate pretreated as described above and then treated with an adhesion promoter, wherein an electrolessly-applied metal layer is disposed on the substrate, and an electrolytically-applied metal layer free of chemical additives is disposed on the electrolessly-applied layer. The article may include an additional electrolytically-applied layer containing chemical additives and disposed on top of the first electrolytic layer.

Abstract: A method for treating a polyimide surface is disclosed, in which an adhesion-promoting compound such as thiourea contacts the surface prior to the electroless plating of metal thereon. Articles formed by such a method are also disclosed.

Abstract: A method of improving the adhesion of metal applied on a polyimide surface is disclosed, in which the surface is first treated with an adhesion-promoting compound containing a nitrogen-oxygen moiety prior to plating of the metal thereon.