Patent ID: 6214501
Filing Date: 2001-04-10
Classification: C09K,H01J

Abstract:
A method for coating phosphor particles with polymers in order to improve chargeability thereof in use for manufacturing a screen on an inner surface of a panel of a CRT, said coating method comprising the steps of:injecting into a reactor with hexane as a solvent, phosphor particles of about 40 to 60 weight % with respect to the solvent, and styrene as a monomer of about 20 to 30 weight % with respect to the solvent, and agitating them in the reactor;maintaining the temperature of the reactor in 60 degrees of centigrade by heating the reactor by a heating mantle and by transferring cool water through a return current cooler mounted on the reactor;preparing 2,2'-azobisisobutyronitrile (AIBN) as first, second and third initiators (catalysts) having same amount of about 0.02 to 0.5 weight % with respect to the monomer, injecting into the reactor with the first initiator, injecting into the reactor with the second initiator after lapse of one hour from the time of injecting the first initiator, and finally injecting into the reactor with the third initiator after lapse of two hours from the time of injecting the second initiator;injecting co-catalyst dissolved in hexane after the third initiator is injected, co-catalyst being cobalt naphthalate of 0.01 to 0.05 weight % with respect to one of the initiator;cooling the reactor after lapse of two hours from the injecting of the co-catalyst;drying naturally after completion of the polymerization so as to drive off the solvent or monomers remained in the reactor;shattering the resultant dried phosphor particles; andfiltering the shattered phosphor particles with a filter.