According to the present invention, there is provided a method for forming a color tube phosphor screen comprising the steps of forming a light-absorbing matrix having holes on a faceplate, coating a silica colloidal solution or an alumina colloidal solution containing a multivalent metal ion in said holes and washing said holes, and forming phosphor layers of three colors in said washed holes. The color tube phosphor screen formed through the method of the present invention has no phosphor residual, especially pigment residual.
A dispersion solution of colloidal silica is coated on a pigment layer composing a filter layer and then dried. Thus, the state of the front surface of the filter layer (pigment layer) is controlled without affecting the filter layer (pigment layer). A phosphor layer is formed on the filter layer (pigment layer).
A method for improving the adherence of a phosphor screen to the face panel of a color cathode ray tube involves placing a UV reflective filter on the inside of the face panel prior to photolithographic forming of the screen, in order to reflect transmitted UV light back onto those areas form which the light emerged, thereby effectively increasing the exposure dosage of those areas.
The single-layer high temperature coating according to the invention, which is applied in particular on a porous substrate, comprises a high silica glaze gel frit, alumina and an emissivity agent consisting of MoSi.sub.2 or Cr.sub.2 O.sub.3, and has the following composition by weight: gel frit: 45 to 55%; MoSi.sub.2 or Cr.sub.2 O.sub.3 : 25 to 50%; Al.sub.2 O.sub.3 : 5 to 20%.
Adherence of the phosphor screen to the face panel of a color cathode ray tube is improved by placing a UV-reflective filter on the inside of the face panel prior to photolithographic forming of the screen, in order to reflect transmitted UV light back onto those areas from which the light emerged, thereby effectively increasing the exposure dosage of those areas.
