1. Field of the Invention
The present invention relates to a method for forming phosphor layers of a plasma display panel (PDP), an apparatus for the method, a filament-like article for the method and a method for manufacturing the filament-like article. More particularly, the present invention relates to a method and apparatus for forming the phosphor layers in grooves each defined between ribs (partition walls) on a substrate in a manufacturing process of the plasma display panel.
2. Related Arts
A PDP is a display panel comprising a pair of substrates (typically, glass plates) disposed opposite to each other with a plasma discharge space sandwiched therebetween. When ultraviolet-ray excitation type phosphor layers disposed in the discharge space are excited by ultraviolet rays generated by electric discharge, the PDP displays colors. The PDP has three kinds of phosphor layers--R (red), G (green) and B (blue).
The phosphor layers of R, G and B are each formed using a process in which phosphor pastes containing phosphor powders are sequentially applied between ribs on a substrate by a screen printing method using a screen mask, followed by drying and sintering (for example, see Japanese Unexamined Patent Publication No. Hei 5(1993)-299019).
However, as the size of the PDP becomes larger, the alignment of ribs and mask-patterns becomes more difficult because of the distortion and extension of the masks. Therefore, it is becoming more difficult to apply phosphor pastes precisely among ribs.