THIN FILM FORMATION ON EXTERNAL SURFACE OF CATHODE-RAY TUBE FACE PLATE

PURPOSE:To form a thin film with uniform thickness in the whole area by preventing a film forming liquid from flowing out to the external surface of a face plate even if a cathode- ray tube is stopped rotating through a process of absorbing the film forming liquid which is accumulated in the peripheral part of a face plate with a film forming liquid absorbing member. CONSTITUTION:A cathode-ray tube has an external casing composed of a funnel 12 joined to the end parts of the side walls 10 of the face plate 11 and an exploxion preventing band 14 to fasten the side walls 10 is attached to the outer circumference of the side walls 10 while having a film forming liquid absorbing part 13 of a sponge-like part between the walls and the band. The width of the part 13 is wider than that of the band 14 and the part 13 comes out to the plate 11 side. Due to the centrifugal force attributed to the rotation of a rotating cathode-ray tube 25, a film forming liquid flows toward the peripheral parts of the plate 11 along the outer surface and the excessive film forming liquid is cattered out of the peripheral parts of the outer surface of the plate and a part of the liquid is accumulated in the peripheral parts. The part 13 thus absorbs the film forming liquid and even if the rotation is stopped, the liquid is prevented from flowing out to the peripheral parts of the outer surface and as a result, the thickness of the film on the outer surface of the plate 11 is made uniform.