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: 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: The effluent stream from a process for producing phenolic compounds is reacted with an aldehyde in the presence of a base to form a water soluble resol which is useful in enhanced oil recovery.

Abstract: The effluent stream from a process for producing phenolic compounds is reacted with an aldehyde in the presence of a base to form a water soluble resol which is useful in enhanced oil recovery.