| 摘要 |
PURPOSE:An aqueous suspension of phosphor and pigment is mixed with a cationic, an anionic, and another anionic emulsions each having a specified film forming temperature, by adding each emulsion in sequence. The mixed suspension is adjusted to be neutral or wealky acidic for application, thereby providing a strong deposition of the phosphor and pigment, and an improved screen finishing workability. CONSTITUTION:A phosphor (e.g., green phosphor comprising ZnS:Cu, Al) is suspended in wate and added with a predetermined amount of an aqueous pigment (e.g., green pigment consisting of Cr2O3) suspension and throughly mixed. While stirring this suspension, it is sequently added and mixed with following emulsions; an anionic emulsion having a minimum film forming temperature of less than 30 deg.C, a cationic emulsion having a minimun film forming temperature of 30 deg.C or less, and an anionic emulsion having an optimum film forming temperature of 30 deg.C or less. The mixed suspension is adjusted to be neutral or weakly acidic by using hydrochloric acid or like, so that pH is equal to 3 or more, preferably greater than 4. The resultant pigment-deposited phosphor is then washed, dehydrated, dried and screen-finished to provide a phosphor useful for color cathode ray tube. |
