| 摘要 |
1,063,592. Laminates and laminating. DOUGLAS AIRCRAFT CO. Inc. June 16, 1964 [June 17, 1963], No. 24991/64. Heading B5N. [Also in Divisions G2 and H4] A screen for a cathode-ray or like tube for absorbing stray light comprises a stack of transparent sheets, e.g. of cellulose acetate or ethyl cellulose, having printed thereon a pattern of fine lines, or crossed lines forming squares, diamonds &c., the patterns being made to register with one another by forming the sheets with lines or a pattern of interengaging conical pips which bear a fixed spatial relation to the patterns. Screens having a directional lightabsorbing effect are made by slightly staggering the lines in successive sheets, this being secured by impressing in the sheets pips with their axes slightly inclined to the normal. The sheets may be secured together with thermoplastic or wet adhesive. To form the sheets a web 10 drawn from a roll 11 is passed between rollers 12, 14, edge portions of which are formed respectively with conical bosses 16 and complementary recesses 18 to produce spaced pips 20 in the web. For this purpose the rollers, or the edge portions thereof, may be heated. The web then passes between correspondingly formed rollers 21, 23, the latter of which is engraved with a line pattern which is printed on the web with a medium supplied by inking rollers 28, 30, whereas the former applies adhesive to the underside of the web by rollers 36, 38. The web passes around the roller 21 and is cut into lengths by rollers 44, 46 carrying a knife 48 and a co-operating groove respectively. The cut lengths are superposed with the printed patterns in registration by means of the interengaging pips and are pressed in a press having platens which are heated if a thermoplastic adhesive is used and which are formed with bosses and recesses corresponding to the pips in the sheets. The edge portions of the completed laminate bearing the pips are trimmed off before it is applied to the C.R. or other screen. In a modified apparatus several units such as that shown are arranged to supply sheets in superposed relation, together with an upper sheet bearing no adhesive, to a pair of laminating rollers which deliver to means for cutting the laminate so made into the required lengths. |
