公开(公告)号：GB1272370A

公开(公告)日：1972-04-26

申请号：GB1592370

申请日：1970-04-03

Applicant: RCA CORP

Inventor： LONG GEORGE ERNEST III ,  GROVE FRANCIS DANIEL ,  BARTCH DONALD WALTER

IPC: C03C17/22 ,  C03C17/34 ,  H01J29/89

Abstract: 1,272,370. Glare-reducing coating. R. C. A. CORPORATION. 3 April, 1970 [3 April, 1969], No. 15923/70. Heading B2E. [Also in Divisions Cl, G2 and H1] A glass viewing member through which in use an optical image is to be viewed includes on its viewing surface a glare-reducing coating having a rough surface and being composed of a lithium silicate material. The surface of the viewing member e.g. the external surface of the face of a television tube may be coated by (a) warming the surface of the glass screen to 30‹C-100‹C., (b) coating the warm surface with an aqueous solution containing 1-10 weight percent of a lithium-stabilized silica sol, the sol having an SiO 2 :Li 2 O mole ratio of 4:1-25:1, e.g. by spraying, (c) drying the coating, (d) and then heating the dry coating at 100‹C-450‹C for 10-60 minutes. As shown in Figure 1, a cathode ray tube includes an evacuated envelope 21 having neck section 23 integral with funnel section 25, a face plate or panel 27 comprising an optical viewing screen joined to funnel section 25 by seal 29 preferably of a devitrified glass, a luminous coating 31 of a phosphor applied to the interior surface of the face plate 27, a lightreflecting coating 33, e.g. of aluminium applied to the luminous coating 31 and a glare reducing coating 35 having a rough external surface composed of a lithium silicate material. The coating 35 may be produced on the face plate when the face plate is a separate assembly, or when it is sealed to the funnel yet part of the evacuated tube, or when it is part of a tube which has already been evacuated and sealed-off. Alternatively, the viewing member may be an implosion protection plate which is to be adhered to the external surface of face plate 27 by a suitable adhesive.