Abstract: Broadly, the present invention is directed to a method for making a mold capable of transferring three-dimensional relief from a textured substrate to thermoplastic composite material. This method comprises the steps of preparing a molding core by loading a press with outer layers of textured substrate and an inner layer comprising a combination of an epoxy non-woven glass mat and a woven glass cloth prepreg. The press is actuated at low pressure while applying heat to pregel said epoxy and then the pressure is increased to form the molding core. Molds are prepared by loading a press with outer layers of said molding core and an inner layer comprising a combination of an epoxy non-woven glass mat and a woven glass cloth prepreg. Finally, the press is actuated at low pressure while applying heat to pregel said epoxy and the increasing the pressure to form said molds. As another aspect of the present invention, a three-dimensional relief is imprinted from a textured substrate to a thermoplastic composite.

Abstract: Disclosed is an improved back-up sheet for backing a workpiece during a small bore drilling process. The sheet also possesses electrical properties making it an ideal candidate as a laminate (reinforcing layer or bonding sheet) in the construction of multi-layer printed wiring boards. The sheet or laminate comprises the cured residue of:(a) polyphenylene oxide;(b) a bisphenol A-type epoxy resin; and(c) an amine hardener for said epxoy resin, the weight ratio of a:b+c ranging from about 1:10 to 1:2.

Abstract: The postformability of laminates particularly decorative laminates, having resin-impregnated paper layers is improved by resin treating at least one of the core layers near the surface of the laminate to render the fibers therein less yielding than those of the other layers.