The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 16, 1996
Filed:
Apr. 19, 1995
Chunghwa Picture Tubes, Ltd., Taoyuan, TW;
Abstract
The inner surface of a video display panel such as cathode ray tube (CRT) glass faceplate is initially coated with a mixture of one of the primary color phosphors, an organic binder such as polyvinyl alcohol (PVA) diluted with water, and a photoresist agent. The organic binder overcomes the poor adhesion to the glass faceplate of the photoresist which typically includes polyvinyl pyrrolidone (PVP) and reduces the oxygen which decreases phosphor exposure time. To overcome PVA and PVP incompatibilities which give rise to nonuniform film thickness, a vinyl pyrrolidone-vinyl alcohol (VP-VA) copolymer is added to the phosphor, organic binder and photoresist mixture in the range of 0.1-30 wt %. The copolymer with both the VP and VA functioning groups serves as a coupling agent between the PVA and PVP and eliminates incompatibilities between these components. The VP-VA copolymer preferably has a VP/VA mole ratio in the range of 20/80 to 80/20.