Electrophotographic apparatus with photosensitive member having surface layer of binder resin and fluoro and/or silicon compound particles

An electrophotographic apparatus is disclosed which has an electrophotographic photosensitive member and a transfer device. The photosensitive member has a conductive support and a photosensitive layer, and further has a surface layer formed of a binder resin, fluorine atom- or silicon atom-containing compound particles incompatible with the binder resin, and a fluorine atom- or silicon atom-containing compound compatible with the binder resin. In the surface layer, the proportion of fluorine atoms and silicon atoms to carbon atoms, (F+Si)/C, as measured by X-ray photoelectron spectroscopy is 0.01 to 1.0. Additionally, the transfer device is a multiple-transfer device.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an electrophotographic apparatus, and more 
particularly to an electrophotographic apparatus having a specific 
electrophotographic photosensitive member and a specific transfer means. 
2. Related Background Art 
Inorganic materials such as zinc oxide, selenium, and cadmium sulfide are 
hitherto known as photoconductive materials used in electrophotographic 
photosensitive members. Organic materials including polyvinyl carbazole, 
phthalocyanine and azo pigments have attracted notice based on the 
advantages that they promise high productivity and are free from 
environmental pollution, and have been put into wide use although they 
tend to be inferior to the inorganic materials in respect of 
photoconductive performance or running performance. In recent years, new 
materials having overcome such disadvantages have been studied, and are 
surpassing the inorganic materials particularly with regard to 
photoconductive performance. 
Meanwhile, electrophotographic photosensitive members are required to have 
various chemical and physical durabilities since they are repeatedly 
affected by charging, exposure, development, transfer, cleaning and charge 
elimination in electrophotographic processes in copying machines or laser 
beam printers. In particular, surface properties of photosensitive 
members, such as surface energy, are concerned in developer transfer 
performance on photosensitive members, contamination of photosensitive 
members and so forth, and are one of the important factors for obtaining 
high-quality images. Most of the above organic photoconductive materials 
have no film forming properties by themselves, and hence they are commonly 
formed into films in combination with binder resins or the like when 
photosensitive layers are formed. Accordingly, properties of :such binder 
resins can be referred to as a factor that greatly influences the surface 
properties such as surface energy. 
Binder resins conventionally used include polyester, polyurethane, 
polyarylate, polyethylene, polystyrene, polybutadiene, polycarbonate, 
polyamide, polypropylene, polyimide, polyamidoimide, polysulfone, 
polyallyl ether, polyacetal, nylon, phenol resins, acrylic resins, 
silicone resins, epoxy resins, urea resins, allyl resins, alkyd resins and 
butyral resins. However, those having better surface properties are being 
studied. 
Incidentally, in recent years, there is a demand for electrophotographic 
processes that can faithfully reproduce color images, and several systems 
have been proposed. Among them, apparatus employing a multiple-transfer 
system are commonly available, in which a photosensitive drum and a 
transfer drum that carries a transfer material such as transfer paper are 
synchronized drum-to-drum and images corresponding to the three primary 
colors or four colors comprised of these three colors and a black color 
added thereto are successively superimposed on the transfer material to 
reproduce a color image. 
One of the problems involved in such a process, is the transfer efficiency 
of the second and subsequent colors at the time of multiple transfer has 
been questioned. More specifically, the transfer of the second and 
subsequent colors is carried out via a developer which has already been 
transferred to a transfer material, and hence such transfer can only more 
indirectly operate than usual transfer. As a result, the developer which 
has not been transferred and is standing on the photosensitive member can 
not be transferred to the side of the transfer material, so only 
low-quality images can be obtained because of faulty transfer. Especially 
when the aforesaid conventional organic photosensitive members are used, 
faulty copying such as uneven transfer at solid image areas or letter 
blank areas caused by poor transfer tends to occur. 
As another problem, the driving load of photosensitive members has been 
questioned. In particular, the step of cleaning to remove the developer 
remaining on the photosensitive member after transfer has a great 
influence on the driving load. As a cleaning method, blade cleaning should 
be employed so that the construction of the apparatus can be made simpler 
and more effective and the space for the apparatus can be saved. Blade 
cleaning usually takes a simple construction in which a platelike elastic 
member made of polyurethane or the like is brought into push contact with 
the surface of the photosensitive member in the direction of its 
generatrix. In the case when, however, the aforesaid conventional organic 
photosensitive members are used, a great contact energy is produced 
between the photosensitive member and the blade, so that a heavy load is 
applied to the driving of the photosensitive member. As a result, a 
disturbance such as uneven drive may occur in the driving of the 
photosensitive member which causes color misregistration wherein images 
corresponding to the second and subsequent colors are misregistered at the 
time of multiple transfer, or faulty copying such as drive pitch 
unevenness wherein the uneven drive comes out as an uneven image density. 
In particular, in apparatus in which as a light source for forming a 
latent image a laser, an LED or a liquid crystal shutter is used to form a 
dotlike minute latent image, the color misregistration on the micron order 
may easily occur unless the dots are superimposed at a high precision at 
the time of multiple transfer, to cause aberration of color tones, a 
decrease in image sharpness, etc. 
SUMMARY OF THE INVENTION 
An object of the present invention is to solve the problems discussed above 
and provide an electrophotographic apparatus that can always obtain images 
with a superior quality. 
To achieve the object, the present invention provides an 
electrophotographic apparatus comprising an electrophotographic 
photosensitive member and a transfer means, wherein; 
said electrophotographic photosensitive member comprises a conductive 
support having on its surface a photosensitive layer, and said 
electrophotographic photosensitive member has a surface layer comprised of 
a binder resin, fluorine atom- or silicon atom-containing compound 
particles incompatible with the binder resin, and a fluorine atom- or 
silicon atom-containing compound compatible with the binder resin; the 
proportion of fluorine atoms and silicon atoms to carbon atoms, (F+Si)/C, 
in said surface layer as measured by X-ray photoelectron spectroscopy 
being from 0.01 to 1.0; and 
said transfer means comprises a multiple-transfer means.

The present invention will be described below in greater detail by giving 
Examples. 
EXAMPLE 1 
In a solution prepared by dissolving 10 parts (parts by weight, the same 
applies hereinafter) of a phenol resin precursor (a resol type) in a mixed 
solvent of 10 parts of methanol and 10 parts of butanol, 10 parts of 
conductive titanium oxide (weight average particle diameter: 0.4 .mu.m) 
whose particles had been coated with tin oxide was dispersed using a sand 
mill to produce a dispersion. The dispersion was applied to the surface of 
an aluminum cylinder of 80 mm in outer diameter and 360 mm in length by 
dip coating, followed by curing at 140.degree. C. to form a conductive 
layer with a volume resistivity of 5.times.10.sup.9 .OMEGA..cm and a 
thickness of 20 .mu.m. 
Next, a solution prepared by dissolving 10 parts of methoxymethylated nylon 
(weight average molecular weight: 30,000, degree of methoxymethylation 
about 30%) represented by the formula: 
##STR1## 
in 150 parts of isopropanol was applied to the surface of the above 
conductive layer by dip coating, followed by drying to form 8 subbing 
layer with a thickness of 1 .mu.m. 
Subsequently, in a solution prepared by dissolving 5 parts of a 
polycarbonate resin (weight average molecular weight: 30,000) represented 
by the formula: 
##STR2## 
in 700 parts of cyclohexanone, 10 parts of an azo pigment represented by 
the formula: 
##STR3## 
was dispersed using a sand mill to produce a dispersion. The dispersion 
was applied to the surface of the above subbing layer by dip coating, 
followed by drying to form a charge generation layer with a thickness of 
0.05 .mu.m. 
Next, a solution prepared by dissolving 10 parts of a triphenylamine 
represented by the formula: 
##STR4## 
and 10 parts of a polycarbonate resin (weight average molecular weight: 
20,000) represented by the formula: 
##STR5## 
in a mixed solvent of 50 parts of monochlorobenzene and 15 parts of 
dichloromethane was applied to the surface of the above charge generation 
layer by dip coating, followed by hot-air drying to form a charge 
transport layer with a thickness of 20 .mu.m. 
Next, in a solution prepared by dispersing and dissolving 1 part of fine 
graphite fluoride powder (weight average particle diameter: 0.23 .mu.m, 
available from Central Glass Co., Ltd.), 6 parts of a polycarbonate resin 
(weight average molecular weight: 80,000) represented by the formula: 
##STR6## 
and 0.1 part of a perfluoroalkyl acrylate/methyl methacrylate block 
copolymer (weight average molecular weight: 30,000) represented by the 
formula: 
##STR7## 
wherein i and j indicate a copolymerization ratio; in a mixed solvent of 
120 parts of monochlorobenzene and 80 parts of dichloromethane, 3 parts of 
a triphenylamine represented by the formula: 
##STR8## 
was dissolved to produce a solution. This solution was applied to the 
surface of the above charge transport layer by spray coating, followed by 
drying to form a protective layer with a thickness of 5 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated by the methods shown below. 
(F+Si)/C 
The photosensitive member was cut out in a size of 4 cm .times.4 cm to 
obtain a sample. On this sample, surface elements were determined using an 
ESCALAB200-X type X-ray photoelectron spectroscope, manufactured by VG Co. 
As an X-ray source, MgCa (300 W) was used, and the measurement was made in 
a depth of several angstroms in a region of 2 mm .times.3 mm. A chart thus 
obtained is shown in FIG. 5. As a result, fluorine atoms were in a content 
of 5.2%, silicon atoms 0% and carbon atoms 81.3% and (F+Si)/C was 0.064. 
Contact angle 
Contact angle to pure water, of the photosensitive member was measured 
using a dropping-type contact angle meter (manufactured by Kyowa Kaimen 
Kagaku K.K.). As a result, the contact angle of the photosensitive member 
of Example 1 was 108 degrees, showing a sufficiently low surface energy. 
Transfer efficiency 
The photosensitive member was set on the electrophotographic photosensitive 
member as shown in FIG. 1 and transfer efficiency at the initial stage was 
measured. Charging was carried out using a scorotoron with a negative 
polarity and exposure was carried out using a laser of 787 nm in 
wavelength. As a developer, a two-component developer with a negative 
polarity was used. Transfer was carried out using a corotoron with a 
positive polarity through a 100 .mu.m thick polyethylene terephthalate 
film. To measure transfer efficiency, a halftone solid pattern was 
outputted in monochrome, where the density of the developer having been 
transferred to a transfer material and the density of the developer having 
remained on the photosensitive member were measured using a reflection 
type Macbeth densitometer, and then a calculation was made with a 
calculation formula: (transferred developer density)/(transferred 
developer density plus remaining developer density). Image density of the 
halftone solid pattern was made to be 0.80 as measured on the transfer 
material using the reflection type Macbeth densitometer. As a result, the 
transfer efficiency was as high as 93%. 
Uneven transfer 
The photosensitive member was set on the electrophotographic photosensitive 
member as shown in FIG. 1 and halftone solid pattern images obtained after 
four-color multiple transfer were outputted. Evaluation on images was made 
on images obtained after continuous output on 1,000 sheets. Image density 
of the halftone solid pattern images was made to be 1.20 on the average as 
measured using a reflection type Macbeth densitometer. As a result, 
uniform images were obtained. 
Blank areas caused by faulty transfer 
The photosensitive member was set on the electrophotographic photosensitive 
member as shown in FIG. 1 and lettering pattern images obtained after 
four-color multiple transfer: were outputted. Evaluation on images was 
made on images obtained after continuous output on 1,000 sheets. As a 
result, uniform lettering patterns were obtained even in lettering 
patterns after output on 1,000 sheets. 
Drive pitch unevenness 
The photosensitive member was set on the electrophotographic photosensitive 
member as shown in FIG. 1 and halftone solid pattern images obtained after 
four-color multiple transfer were outputted. Evaluation on images was made 
on images obtained after continuous output on 1,000 sheets. As a result, 
uniform patterns were obtained even in halftone solid patterns after 
output on 1,000 sheets. 
Color misregistration 
The photosensitive member was set on the electrophotographic photosensitive 
member as shown in FIG. 1 and gray halftone solid pattern images obtained 
after four-color multiple transfer were outputted. Evaluation on images 
was made on images obtained after continuous output on 1,000 sheets. As a 
result, patterns with uniform color tones were obtained even in gray 
halftone solid patterns after output on 1,000 sheets. 
Comparative Example 1 
An electrophotographic photosensitive member was produced in the same 
manner as in Example 1 except that the protective layer was not provided. 
Performance thereof was similarly evaluated. 
Results obtained are shown below. 
(F+Si)/C 
As shown in FIG. 7, fluorine atoms and silicon atoms were each in a content 
of 0%, and (F+Si)/C was 0. 
Contact angle 
Contact angle was 82 degrees. 
Transfer efficiency 
Transfer efficiency was 86%. 
Uneven transfer 
Blank areas caused by faulty transfer were partly seen, and images were 
greatly coarse and non-uniform. 
Blank areas caused by faulty transfer 
Blank areas caused by faulty transfer as shown in FIG. 8 were seen, where 
portions other than contours of lettering patterns came off because of 
faulty transfer. 
Drive pitch unevenness 
Irregular stripelike unevenness occurred in images in their directions of 
the rotation of the photosensitive member. 
Color misregistration 
Reddish color tone unevenness occurred in part. This outputted image was 
observed with a microscope to reveal that the magenta image among the four 
colors was misregistered by 50 to 90 .mu.m in a dotlike image formed of 
four-color dots superimposed one another, showing that the uneven color 
tone was due to microscopic color misregistration. 
EXAMPLE 2 
Example 1 was repeated to form the conductive layer, the subbing layer and 
the charge generation layer on the aluminum cylinder. 
Next, a charge transport layer was formed in the same manner as in Example 
1 except that the triphenylamine used therein was replaced with a 
triphenylamine represented by the formula: 
##STR9## 
Next, in a solution prepared by dispersing and dissolving 3 parts of fine 
graphite fluoride powder (weight average particle diameter: 0.23 .mu.m, 
available from Central Glass Co., Ltd.), 6 parts of a polycarbonate resin 
(weight average molecular weight: 80,000) represented by the formula: 
##STR10## 
and 0.3 part of a perfluoroalkyl acrylate/methyl methacrylate block 
copolymer (weight average molecular weight: 30,000) represented by the 
formula: 
##STR11## 
wherein i and j indicate a copolymerization ratio; in a mixed solvent of 
110 parts of monochlorobenzene and 80 parts of dichloromethane, 2.5 parts 
of a triphenylamine represented by the formula: 
##STR12## 
was dissolved to produce a solution. This solution was applied to the 
surface of the charge transport layer by spray coating, followed by drying 
to form a protective layer, with a thickness of 6 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated in the same manner as in Example 1. As a result, the 
fluorine atoms were in a content of 10.2%, silicon atoms 0% and carbon 
atoms 76.7%, the (F+Si)/C was 0.13, and the contact angle was 113 degrees. 
The transfer efficiency was 96%, and very good images were obtainable 
without any uneven transfer, blank areas caused by faulty transfer, drive 
pitch unevenness and color misregistration. 
EXAMPLE 3 
Example 1 was repeated to form the conductive layer, the subbing layer and 
the charge generation layer on the aluminum cylinder. 
Next, a charge transport layer was formed in the same manner as in Example 
1 except that 10 parts of the triphenylamine used therein was replaced 
with 3 parts of a triphenylamine represented by the formula: 
##STR13## 
and 7 parts of a triphenylamine represented by the formula: 
##STR14## 
Next, in a solution prepared by dispersing and dissolving 3 parts of fine 
graphite fluoride powder (weight average particle diameter: 0.27 .mu.m, 
available from Central Glass Co., Ltd.), 5.5 parts of a polycarbonate 
resin (weight average molecular weight: 80,000) represented by the 
formula: 
##STR15## 
and 0.3 part of a fluorine atom-containing graft polymer (fluorine 
content: 27% by weight; weight average molecular weight: 25,000) 
represented by the formula: 
##STR16## 
wherein i and j indicate a copolymerization ratio; in a mixed solvent of 
120 parts of monochlorobenzene and 80 parts of dichloromethane, 2.5 parts 
of a triphenylamine represented by the formula: 
##STR17## 
was dissolved to produce a solution. This solution was applied to the 
surface of the charge transport layer by spray coating, followed by drying 
to form a protective layer with a thickness of 4 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated in the same manner as in Example 1. As a result, the 
fluorine atoms were in a content of 11.3%, silicon atoms 0% and carbon 
atoms 75.5%, the (F+Si)/C was 0.15, and the contact angle was 114 degrees. 
The transfer efficiency was 96%, and very good images were obtainable 
without any uneven transfer, blank areas caused by faulty transfer, drive 
pitch unevenness and color misregistration. 
EXAMPLE 4 
An electrophotographic photosensitive member was produced in the same 
manner as in Example 1 except that the fluorine atom-containing graft 
polymer used therein was replaced with the perfluoroalkyl acrylate/methyl 
methacrylate block copolymer as used in Example 1. Performances thereof 
were similarly evaluated. 
As a result, the fluorine atoms were in a content of 12.2%, silicon atoms 
0% and carbon atoms 73.2%, the (F+Si)/C was 0.17, and the contact angle 
was 115 degrees. The transfer efficiency was 95%, and very good images 
were obtainable without any uneven transfer, blank areas caused by faulty 
transfer, drive pitch unevenness and color misregistration. 
EXAMPLE 5 
Example 1 was repeated to form the conductive layer, the subbing layer and 
the charge generation layer on the aluminum cylinder. 
Next, a solution prepared by dissolving 3 parts of a triphenylamine 
represented by the formula: 
##STR18## 
7 parts of a triphenylamine represented by the formula: 
##STR19## 
and 10 parts of a polycarbonate resin (weight average molecular weight: 
25,000) represented by the formula: 
##STR20## 
in a mixed solvent of 50 parts of monochlorobenzene and 15 parts of 
dichloromethane was applied to the surface of the charge generation layer 
by dip coating, followed by hot-air drying to form a charge transport 
layer with a thickness of 20 .mu.m. 
Next, in a solution prepared by dispersing and dissolving 3 parts of fine 
tetrafluoroethylene/hexafluoropropylene copolymer powder (monomer ratio: 
tetrafluoroethylene/hexafluoropropylene=3/7; an emulsion polymerization 
fine powder; weight average particle diameter: 0.32 .mu.m, weight average 
molecular weight: 600,000), 5.5 parts of a polycarbonate resin (weight 
average molecular weight: 100,000) represented by the formula: 
##STR21## 
and 0.3 part of a perfluoroalkyl acrylate/methyl methacrylate block 
copolymer (weight average molecular weight: 30,000) represented by the 
formula: 
##STR22## 
wherein i and j indicate a copolymerization ratio; in a mixed solvent of 
100 parts of monochlorobenzene and 70 parts of dichloromethane, 2.5 parts 
of a triphenylamine represented by the formula: 
##STR23## 
was dissolved to produce a solution. This solution was applied to the 
surface of the charge transport layer by spray coating, followed by drying 
to form a protective layer with a thickness of 5 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated in the same manner as in Example 1. As a result, the 
fluorine atoms were in a content of 9.5%, silicon atoms 0% and carbon 
atoms 80.5%, the (F+Si)/C was 0.12, and the contact angle was 112 degrees. 
The transfer efficiency was 96% and very good images were obtainable 
without any uneven transfer, blank areas caused by faulty transfer, drive 
pitch unevenness and color misregistration. 
Comparative Example 2 
Example 1 was repeated to form the conductive layer, the subbing layer and 
the charge generation layer on the aluminum cylinder. 
Next, a solution prepared by dissolving 10 parts of a triphenylamine 
represented by the formula: 
##STR24## 
and 10 parts of a polycarbonate resin (weight average molecular weight: 
25,000) represented by the formula: 
##STR25## 
in a mixed solvent of 50 parts of monochlorobenzene and 15 parts of 
dichloromethane was applied to the surface of the charge generation layer 
by dip coating, followed by hot-air drying to form a charge transport 
layer with a thickness of 20 .mu.m. 
Next, in a solution prepared by dispersing and dissolving 0.3 part of fine 
graphite fluoride powder (weight average particle diameter: 0.27 .mu.m, 
available from Central Glass Co., Ltd.), 6.4 parts of a polycarbonate 
resin (weight average molecular weight: 80,000) represented by the 
formula: 
##STR26## 
and 0.03 part of a perfluoroalkyl acrylate/methyl methacrylate block 
copolymer (weight average molecular weight: 30,000) represented by the 
formula: 
##STR27## 
wherein i and j indicate a copolymerization ratio; in a mixed solvent of 
120 parts of monochlorobenzene and 80 parts of dichloromethane, 3.2 parts 
of a triphenylamine represented by the formula: 
##STR28## 
was dissolved to produce a solution. This solution was applied to the 
surface of the charge transport layer by spray coating, followed by drying 
to form a protective layer with a thickness of 5 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated in the same manner as in Example 1. As a result, the 
fluorine atoms were in a content of 0.83%, silicon atoms 0% and carbon 
atoms 85.5% the (F+Si)/C was 0.0097, and the contact angle was 83 degrees. 
The transfer efficiency was 87%, and uneven transfer, blank areas caused 
by faulty transfer, drive pitch unevenness and color misregistration 
occurred. 
EXAMPLE 6 
Example 1 was repeated to form the conductive layer, the subbing layer, the 
charge generation layer and the charge transport layer on the aluminum 
cylinder. 
Next, in a solution prepared by dispersing and dissolving 1 part of a 
truely spherical three-dimensional cross-linked fine polysiloxane 
particles (weight average particle diameter: 0.29 .mu.m, available from 
Toshiba Silicone Co., Ltd.), 6 parts of a polycarbonate resin (weight 
average molecular weight: 80,000) represented by the formula: 
##STR29## 
and 0.1 part of a polydimethylsiloxane methacrylate/methyl methacrylate 
block copolymer (silicon content: 22% by weight; weight average molecular 
weight: 50,000) represented by the formula: 
##STR30## 
wherein i and j indicate a copolymerization ratio; in a mixed solvent of 
120 parts of monochlorobenzene and 80 parts of dichloromethane, 3 parts of 
a triphenylamine represented by the formula: 
##STR31## 
was dissolved to produce a solution. This solution was applied to the 
surface of the charge transport layer by spray coating, followed by drying 
to form a protective layer with a thickness of 3 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated in the same manner as in Example 1. 
(F+Si)/C 
A chart obtained by X-ray photoelectron spectroscopy is shown in FIG. 6. As 
a result, the fluorine atoms were in a content of 0%, silicon atoms 10.2% 
and carbon atoms 62.3%, and the (F+Si)/C was 0.16. 
Contact angle 
Contact angle was 107 degrees. 
Transfer efficiency 
Transfer efficiency was 92%. 
Uneven transfer 
Like Example 1, uniform images were obtained. 
Blank areas caused by faulty transfer 
Like Example 1, uniform lettering patterns were obtained. 
Drive pitch unevenness 
Like Example 1, uniform patterns were obtained. 
Color misregistration 
Like Example 1, patterns with uniform color tones were obtained. 
EXAMPLE 7 
Example 2 was repeated to form the conductive layer, the subbing layer, the 
charge generation layer and the charge transport layer on the aluminum 
cylinder. 
Next, in a solution prepared by dispersing and dissolving 3 parts of a 
truely spherical three-dimensional cross-linked fine polysiloxane 
particles (weight average particle diameter: 0.29 .mu.m, available from 
Toshiba Silicone Co., Ltd.), 4 parts of a polycarbonate resin (weight 
average molecular weight: 80,000) represented by the formula: 
##STR32## 
and 0.3 part of a polydimethylsiloxane methacrylate/styrene block 
copolymer (silicon content: 22% by weight; weight average molecular 
weight: 60,000) represented by the formula: 
##STR33## 
wherein i and j indicate a copolymerization ratio; in a mixed solvent of 
120 parts of monochlorobenzene and 80 parts of dichloromethane, 2.5 parts 
of a triphenylamine represented by the formula: 
##STR34## 
was dissolved to produce a solution. This solution was applied to the 
surface of the charge transport layer by spray coating, followed by drying 
to form a protective layer with a thickness of 3 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated in the same manner as in Example 1. As a result, the 
fluorine atoms were in a content of 0%, silicon atoms 15.1% and carbon 
atoms 58.1%, the (F+Si)/C was 0.26, and the contact angle was 110 degrees. 
The transfer efficiency was 94%, and very good images were obtainable 
without any uneven transfer, blank areas caused by faulty transfer, drive 
pitch unevenness and color misregistration. 
EXAMPLE 8 
Example 3 was repeated to form the conductive layer, the subbing layer, the 
charge generation layer and the charge transport layer on the aluminum 
cylinder. 
Next, in a solution prepared by dispersing and dissolving 3 parts of a 
truely spherical three-dimensional cross-linked fine polysiloxane 
particles (weight average particle diameter: 0.29 .mu.m, available from 
Toshiba Silicone Co., Ltd.), 4 parts of a polycarbonate resin (weight 
average molecular weight: 80,000) represented by the formula: 
##STR35## 
and 0.35 part of a silicon atom-containing graft copolymer (weight average 
molecular weight: 35,000) represented by the formula: 
##STR36## 
wherein i, j and k indicate a copolymerization ratio, and m and n each 
represent a positive integer; 
in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of 
dichloromethane, 2.5 parts of a triphenylamine represented by the formula: 
##STR37## 
was dissolved to produce a solution. This solution was applied to the 
surface of the charge transport layer by spray coating, followed by drying 
to form a protective layer with a thickness of 3.5 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated in the same manner as in Example 1. As a result, the 
fluorine atoms were in a content of 0%, silicon atoms 16.3% and carbon 
atoms 57.3%, the (F+Si)/C was 0.28, and the contact angle was 110 degrees. 
The transfer efficiency was 94%, and very good images were obtainable 
without any uneven transfer, blank areas caused by faulty transfer, drive 
pitch unevenness and color misregistration. 
EXAMPLE 9 
An electrophotographic photosensitive member was produced in the same 
manner as in Example 8 except that the silicon atom-containing graft 
polymer used therein was replaced with the polydimethylsiloxane 
acrylate/methyl methacrylate block copolymer as used in Example 6. 
Performances thereof were similarly evaluated. 
As a result, the fluorine atoms were in a content of 0%, silicon atoms 
15.6% and carbon atoms 58.5%, the (F+Si)/C was 0.27, and the contact angle 
was 110 degrees. The transfer efficiency was 94%, and very good images 
were obtainable without any uneven transfer, blank areas caused by faulty 
transfer, drive pitch unevenness and color misregistration. 
Comparative Example 3 
Comparative Example 2 was repeated to form the conductive layer, the 
subbing layer, the charge generation layer, and the charge transport layer 
on the aluminum cylinder. 
Next, in a solution prepared by dispersing and dissolving 0.5 part of a 
truely spherical three-dimensional cross-linked fine polysiloxane 
particles (weight average particle diameter: 0.29 .mu.m, available from 
Toshiba Silicone Co., Ltd.) and 4 parts of a polycarbonate resin (weight 
average molecular weight: 80,000) represented by the formula: 
##STR38## 
in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of 
dichloromethane, 2.5 parts of a triphenylamine represented by the formula: 
##STR39## 
was dissolved to produce a solution. This solution was applied to the 
surface of the charge transport layer by spray coating, followed by drying 
to form a protective layer with a thickness of 3 .mu.m. 
Performances of the electrophotographic photosensitive member thus obtained 
were evaluated in the same manner as in Example 1. As a result, the 
fluorine atoms were in a content of 0.%, silicon atoms 0.53% and carbon 
atoms 83.3%, the (F+Si)/C was 0.0064, and the contact angle was 82 
degrees. The transfer efficiency was 84%, and uneven transfer, blank areas 
caused by faulty transfer, drive pitch unevenness and color 
misregistration occurred.