Process for preparing a toner resin, toner resin prepared thereby and toner composition containing particles of the toner resin
AssigneeMitsui Toatsu Chemicals, Inc.
InventorsNobuki Kobayashi, Richard L. Hively
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Abstract
A toner resin suitable for being used in toner compositions or developer compositions for electrostatic imaging is prepared by polymerization of styrene and butadiene in the presence of a mixture of n-dodecyl mercaptan and t-dodecyl mercaptan. The toner resin has defined weight average and number average molecular weights and a defined polydispersity that provide an improved toner resin that can be attained without blending different copolymers while using conventional apparatus. Additionally, the toner resin can exhibit a suitable melt index and glass transition temperature.
Claims17
A process for preparing a toner resin comprising polymerizing styrene and butadiene in a weight ratio of styrene to butadiene of from about 85:15 to about 97:3 in the presence of a mixture of n-dodecyl mercaptan and t-dodecyl mercaptan in a weight ratio of from about 1:9 to about 9:1 to form said toner resin wherein said toner resin has a weight average molecular weight of from about 50,000 to about 140,000, a number average molecular weight of from about 5,000 to about 13,000, a polydispersity of from about 5 to about 15 and a melt index of from about 5 to about 80 g/10 min.
Dependencies are inferred from the claim text.