Electrophotographic member with surface layer having fluorine resin powder and fluorine graft polymer

#1. Field of the Invention

#This invention relates to an electrophotographic photosensitive member, more particularly to an electrophotographic photosensitive member of high durability excellent in humidity resistance and mechanical strength.

#2. Related Background Art

#The present invention is described in more detail by referring to Examples.

#Fluorine type graft polymers were synthesized on the basis of the macromer synthetic method disclosed in Japanese Laid-open Patent Publication No. 164656/1983 in which the terminal double bond is introduced with glycidyl methacrylate by use of thioglycolic acid as the chain transfer agent. When this macromer is a non-fluorine type segment, copolymerization with a fluorine type polymerizable monomer was conducted, while when the macromer is fluorine type segment, copolymerization with a non-fluorine type polymerizable monomer was conducted to synthesize a fluorine type graft polymer.

#A glass flask equipped with an agitator, a reflux condenser, a dropping funnel, thermometer and a gas blowing inlet was charged with 10 parts of methyl methacrylate (hereinafter abbreviated as MMA) and 90 parts of a solvent mixture of acetone (17.5%)toluene and, after introduction of N.sub.2, polymerization was initiated under reflux by adding 0.5 parts of azobisisobutylonitrile (hereinafter abbreviated as AIBN) as the polymerization initiator and 0.35 parts of thioglycolic acid as the chain transfer agent. Then, within 5 hours, 90 parts of MMA were added dropwise continuously, and a solution of 2.9 parts of thioglycolic acid dissolved in 10 parts of toluene was added in 9 divided portions every 30 minutes, and similarly 1.5 parts of AIBN was added similarly in 4 divided portions every one hour to carry out polymerization. Further, the mixture was thereafter refluxed for 2 hours to complete polymerization and give a polymer solution of the following structural formula [I]. The reaction temperature was 77 to 87.degree. C. A part of the reaction mixture was reprecipitated with n-hexane and dried. The acid value of the polymer was measured to b 0.350 mg equivalent/g. ##STR20##