| 摘要 |
1482773 Laminates MICA CORP 26 July 1974 [27 July 1973] 33128/74 Heading B5N [Also in Divisions H1 and C7] Printed circuit board material comprises an insulating support, a layer of electrical resistance material, adhering to the support and a layer of highly conductive material adhering to the resistance material and in intimate contact therewith, the layer of electrical resistance material comprising chromium-antimony, chromium - magnenese, chromium - phosphorus, chromium - selenium, chromium - tellurium, cobalt - antimony, cobalt - boron, cobaltgermanium, cobalt - indium, cobalt - molybdenum, cobalt-phosphorus, cobalt - rhenium, cobalt - ruthenium, cobalt - tungsten, cobaltvanadium, iron - vanadium, nickel - antimony, nickel - boron, nickel - germanium, nickelindium, nickel - molybdenum, nickel-rhenium, nickel - vanadium or palladium - molybdenum. The resistance material may be applied to the highly conductive material, e.g. a foil of copper, tinned copper, aluminium, zinc or silver, by electro-plating, electroless deposition or vapour deposition, optionally heated, and then laminated to the insulating support which may be a polyimide, epoxy resin or polyester resin containing glass fibre fabric, or paper impregnated with phenolic or melamic resin. A layer of highly thermally conductive material, e.g. aluminium or copper foil, may be included in the insulating support or bonded to the side thereof opposite the resistance material. A printed circuit may be produced from the board material by etching away both the highly conductive material and resistance material in desired areas with the aid of a photoresist, and then etching away only the highly conductive material in further desired areas, again with the aid of a photoresist, so that the conductive and resistive patterns are individually defined. |
