Abstract:
A method for coating cloth especially fiberglass sheets with a thermosetting resin and resulting structure is provided. The coating is performed in two steps. In the first step, essentially all of the strands of the fiberglass are coated with the resin/solvent mixture while maintaining at least some of the interstices or openings essentially free of the solvent mixture. This first coating is then partially cured to between about 70% and 90% of full cure. The coated fiberglass with partially cured resin thereon is then given a second coating of either the same or different thermosetting resin mixture which coats the first coating and fills in the interstices between the fibers. This second coating is then partially cured, which advances the cure of the first coating past 80% full cure and results in an impregnated fiberglass cloth structure for use as sticker sheets. During lamination, the first coating acts like an impenetrable insulating sheet, preventing resin displacement and, therefore, preventing glass fiber contact with the conductive planes. The second coating is fluid enough to fill in spaces in the planes and to form the adhesive bond to cores and conductive layers. The structure reduces the tendency of the resin to flake and produce dust during subsequent processing operations.
Abstract:
Flexible wiring boards showing a small electrical resistance and yet having a small width. The flexible wiring board according to the invention has a first wiring film and a second wiring film. Since the first wiring film has a larger thickness than the second wiring film, the sectional area and electrical resistance of the first wiring film can be enlarged because of the larger film thickness even in a case where the first and second wiring films have almost the same width. Therefore, a high current can flow through the first wiring film, though the wiring film has a small width. As a result, a high density of the flexible wiring board can be easily achieved.
Abstract:
Disclosed is a method for producing a patterned calcined inorganic film such as an electroconducting or insulating (non-conductive) film, particularly a plasma display panel, embracing a calcining step. To produce a patterned calcined inorganic film without inducing warpage, shrinkage of line width, or breakage of patterned lines, a patterned film formed on a substrate with a composition containing a heat decomposable binder and particles of an inorganic material is covered, prior to the calcining step, with a coating film of a heat decomposable resin composition capable of hardening or drying at a temperature lower than the temperature at which the heat decomposable binder is thermally decomposed and further capable of being burned off below the highest temperature of the calcining profile and thereafter the calcining step is performed.
Abstract:
A method for coating cloth especially fiberglass sheets with a thermosetting resin and resulting structure is provided. The coating is performed in two steps. In the first step, essentially all of the strands of the fiberglass are coated with the resin/solvent mixture while maintaining at least some of the interstices or openings essentially free of the solvent mixture. This first coating is then partially cured to between about 70% and 90% of full cure. The coated fiberglass with partially cured resin thereon is then given a second coating of either the same or different thermosetting resin mixture which coats the first coating and fills in the interstices between the fibers. This second coating is then partially cured, which advances the cure of the first coating past 80% full cure and results in an impregnated fiberglass cloth structure for use as sticker sheets. During lamination, the first coating acts like an impenetrable insulating sheet, preventing resin displacement and, therefore, preventing glass fiber contact with the conductive planes. The second coating is fluid enough to fill in spaces in the planes and to form the adhesive bond to cores and conductive layers. The structure reduces the tendency of the resin to flake and produce dust during subsequent processing operations.
Abstract:
A process for roughening a metal surface is provided comprising applying a coating to the metal surface wherein the coating is a temporary barrier to an etchant attacking the metal surface and the coating is susceptible to the etchant gradually removing the coating, and then etching the coated metal surface with an aqueous bath containing the etchant effective to produce a roughened metal surface.
Abstract:
A differentiable ablation approach to patterning dielectrics which are not of the same absorbance uses an absorbant dielectric at a specified laser wavelength over a non-absorbant dielectric at that wavelength. The absorbant dielectric may be laser-patterned and become an integral mask enabling plasma etching of the underlying non-absorbant dielectric. If the patterning of the absorbant dielectric involves vias, polymer ridges formed around via surfaces during laser patterning may be removed at the same time the underlying non-absorbant dielectric is etched using a transparent, oxygen plasma resistant mask. Alternatively, an inert mask may be used instead of the absorbant dielectric to allow plasma etching of the non-absorbant dielectric.
Abstract:
A water-soluble coating or other deposit is produced from a formulation that is comprised of a curable liquid substance and a dispersed particulate effervescing agent. The formulation is particularly useful as a solder resist in the manufacture of PCBs, and the preferred composition contains n-vinyl-2-pyrrolidone, N,N-dimethylacrylamide, and polyvinylpyrrolidone.
Abstract:
Trenching techniques for forming a channel partially through and a via completely through the insulating layer of a substrate are disclosed. With additional steps the channel can form an electrically conductive line, an electrode of an integrated capacitor, or an optical waveguide.
Abstract:
A process of forming solder lands in a printed wiring board manufacturing method is disclosed. The process comprises a step of forming a wiring circuit of a required pattern by a copper foil provided on an electrical insulating sheet, a step of forming required solder resists on the wiring circuit, a preprinting step for leveling the surface of the wiring circuit and a step of printing required solder resist on the wiring circuit.
Abstract:
This invention relates to an adhesion promoting composition and method for its use for promoting adhesion of printed circuits on thermoplastic substrates. The composition includes isopropanol with either methylene chloride or resorcinol. An added ingredient includes polycyclohexanone. The preferred substrate is polyarylsulfone.