GB1146289A - Scribe material - Google Patents

Abstract

1,146,289. Photographic scribe materials. KEUFFEL & ESSER CO. March 1, 1966 [March 1, 1965], No.8928/66. Heading G2C. [Also in Division C7] A scribe material (i.e. sheet material part of the depth of which can be removed by manual incizing with a sharp tool to give a relief effect) includes a support layer, a scribe layer (i.e. a uniform pigmented layer of which a part can be readily removed by scribing to give a clean relief effect), a deposited thin metal layer which is at least thick enough to increase the actiric density of the scribe material but not thick enough to inhibit clean scribing, the scribe layer being between the other layers, and a photo-sensitive layer may be provided on the metal layer, which on exposure provides images which can be used as a guide in scribing. There may be scribe, metal and photosensitive layers on both sides of the support layer. The support layer may be cellulose acetate, polyacrylate, polycarbonate, polyethylene, polyester, polypropylene, polyethylene terephthalate, laminates with phenol-formaldehyde resin, or glass, and may be transparent or not, and preferably 0À002-0À04 inches thick. The scribe layer may for example comprise 2 parts by weight an alkali-soluble alkyd resin, 9 parts titanium dioxide, 0À016 parts cobalt naphthenate drier and 9 parts solvent such as xylol, toluol or ethyl acetate. Coloured pigments, such as chrome yellow molybdate orange, carbon black may be used, or dyes may be added. There may also be added, up to 10% of the resin content, urea and melamine formaldehyde resin, and nitrocellulose up to 75% of resin content if plasticizers are also added. The metal layer may be aluminium, chromium, copper, nickel, gold, silver or other metal deposited by evaporation, sputtering, chemical deposition or electrolytically. If the scribe material is translucent, scribing can be carried out on an illuminated table. One method of scribing is by cutting the image in outline and stripping away the scribe layer within the outline, which method is used for lithography and map-making. Printed circuits for test boards can be laid out by removing part of the metal layer, leaving metallic conductive lines.