Photomechanical method of making metallic patterns

Abstract

Abstract 1,035,327. Printed circuits. INTERNATIONAL BUSINESS MACHINES CORPORATION. Sept. 30, 1963 [Oct. 3, 1962], No. 38360/63. Heading H1R. In a method of making a printed circuit of a desired configuration, a master pattern is produced which comprises a plurality of points and interconnections therebetween corresponding to terminal areas and conductors in the printed circuit, there being sufficient interconnections to include the conductors necessary for a plurality of different circuit configurations; and a break pattern is produced which, when superposed on the master pattern, covers areas on the latter where breaks in conductors are desired; and the two patterns are combined to form the desired circuit in metal on an insulating support. As described, the master pattern is drawn on vellum and reproduced as a transparency; Fig. 2 shows points 32, 34, 36, 38 interconnected by vertical lines 48 and by horizontal lines 46a, 46b, 46c, 46d, additional vertical lines 40, 42, 44 being provided to increase the interpoint connection potential. A break pattern, Fig. 3 (not shown), is prepared comprising a circle 50<SP>1</SP> or other shape, wherever a break in the horizontal or vertical lines is required. The master pattern may be a negative and the break pattern a positive, the two patterns being superposed on a copper-clad insulating board in a photo-etching process to produce a printed circuit, part of which is depicted in Fig. 7 (not shown). Other master patterns may be used, e.g. where points are interconnected only diagonally, and the etch resist may be applied by silk screening or printing. The method may be adapted for a conductor additive process. A plurality of printed circuit boards made according to the invention may be stacked and laminated, interconnection between desired terminal areas in different planes being effected by through-plated holes. The combination of a pattern of disconnected terminal points and a pattern of connections is mentioned in the Specification.

Inventors

• 👤 Herman F Koehler

Bibliographic Details