CA1044067A - Use of fluorinated resins to tailor the triboelectric properties of photoconductive insulating layers - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Method for modifying the triboelectric charge ex-change between electroscopic toner particles and the imaging surface of an electrostatographic imaging member. This modi-fication is achieved by overcoating the imaging layer of the photoreceptor with a film comprising a fluorinated resin; or by inclusion of said fluorinated resin within the matrix of the imaging layer. This ability to modify the relative tribo-electric relationship between the toner particles and the imag-ing layer of the photoreceptor enables the ready adaption of development and cleaning systems designed for use with a specific photoreceptor based imaging system (e.g. amorphous selenium imag-ing members),to other imaging systems utilizing dissimilar imaging members (e. g. binder layer imaging members).

Description

BACKGROUND OF THE I~VENTION

Field of the Invention - This invention relates to a method, an article and a process. More specifically, this invention involves a method for the modification or tailoring of the triboelectric exchange between toner particles and the imaging surface of an electrostatographic imaging member. This ability to tailor the triboelectric exchange ~etween these -materials permits adaption of development and cleaning systems, originally designed for use with a specific photoconductive in-sulating layer, to other imaging systems utilizing dissimilar photoconductive insulating layers.
Description of the Prior Art - In the evolution of the modern plain paper copier it has been necessary to redesign . .
one or more processing stations within these machines to achieve better quality copies and more rapid copying speeds. Often, the replacement of a single element within these highly sophisticated - -- devices will necessitate extensive mod~fication of other processing~
stations. Such extensive modification o~f these machines is not only~costly in terms of capital ex~diture but also results ~20 in lost revenues during the period when-~he machine is taken out of service to undergo this retrofiting. Thus, there is often reluctance to attempt to upgrade an exis~ing machine because of ---- the impact that even minor changes may have on the various proces-sing stations within the copier. This is especially true inc~T~"
plation of replacement of one type of ph~toreceptor with another.
The triboelectric relationship between the charged electroscopic toner particles (used in t~e developement of a latent electrostatic image) and the imag;mg layer ~upon which the latent image is formed) is critical ~or the attraction of toner particles during the development p~-ase of the copying cycle and the removal of toner particles during the transfer and . . .. .... . . . . . . . . . .. . 3 ~

cleaning phases of the copying cycle. With the increasing pop-ularity of organic photoconductive polymeric materials and photo-conductive binder layers, it would indeed be highly advantageous to be able to identify a photoconcluctive insulating material or -~binder layer whose inherent triboelectric properties closely approximate those of a photoconductive insulating layer current- -ly in use in an existing commercial copying system since such a photoconductor would probably be highly compatible with the other existing processing stations in such a machine. Alternatively, the ability to modify or tailor the inherent tribolectric prop-erties of a photoconductive insulating layer so as to approxi-mate those of a commercially used photoreceptor would also be equally advantageous.
Accordingly, it is an object of an aspect of this invention to eliminate the above and related deficiencies in the prior art.
It is an object of an aspect of this invention to provide a method for modification of the inherent triboelectric properties of a photoconductive insulating layer.
It is an object of an aspect of this invention to provide a method for tailoring the triboelectric properties of a photoconductive insulating layer so as to approximate those of a photoconductor used in a commercial electrostatographic copy-ing system.
It is an object of an aspect of this invention to provide a method for tailoring the triboelectric properties of an organic photoconductive polymeric material so as to approxi-mate the triboelectric properties of amorphous selenium.
It is an object of an aspect of this invention to pro-vide a method for tailoring the triboelectric properti~s of a photoconductive binder layer so as to approximate the tribo-electric properties of amorphous selenium.

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Additional objects and aspects of this invention include providing organic photoconductive polymeric materials and photoconductive binder systems having triboelectric proper-ties comparable with amorphous selenium and the use of these photoconductive materials in an electrostatographic imaging system.
SUMMARY OF THE INVENTION
In accordance with one aspect of this invention there is provided a method for modifying the triboelectric properties of the photoconductive imaging layer of an electro-statographic imaging member comprising incorporating into said layer a triboelectric modifying effective amount of a phase -~
compatible fluorinated resin other than a fluorocarbon resin.
In accordance with another aspect of this invention there is provided a triboelectrically modified electrostato-..graphic imaging member comprising a conductive substrate having operatively disposed in relation to at least one surface there of a triboelectrically modified photoconductive imagin~ layer ' having a dry film thickness of from about 1-50 microns and having incorporated therein a triboelectric modifying effective ,, amount of a phase compatible fluorinated resin other than a '~ ;
fluorocarbon resin.
In accordance with another aspect of this invention there is provided an electrostatographic imaging process com-prising: (a) providing a triboelectrically modified imaging :~
member comprising a conductive substrate having operatively disposed in relation to at least one surface thereof a tribo-electrically modified photoconductive imaging layer having a dry film thickness of from about 1-50 microns and having incorporated therein a triboelectric modifying effective amount - ~ -5-., ' . . . - ;. : :, . -.. . .

of a phase compatible flurinated resin other than a fluoro-carbon resin; and (b) forming a latent electrostatic image on the imaging surface of the triboelectrically modified photo-conductive imaging layer.
Especially preferred fluorinated resins which C ~ -5a-, . . . . . . ... ..... , .... .. . . ~ . . .

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can be added to such photoconductive insulating layers included fluorinated epoxy resins and fluorinated acrylic resins.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is an elevational view in vertical cross-section through a device used in evaluation of the triboelectric properties of an electrostatographic imaging member.
Fig. 2 is a graphical illustration of the shift in triboelectric properties of an imaging layer as a function of fluorinated resin concentration.

INCLVDING PREFERRED EMBODIMENTS ^ ~
According to the method of this invention, the tribo- ` -electric properties of the imaging layer of an electrostato-graphic imaging member are modified by the inclusion therein of sufficient fluorinated resin to shift the triboelectric ~;
properties of said layer--to the extent desired.- The degree of modification required will vary depending upon the inherent triboelectric properties of the photoconductive insulating layer; the relative triboelectric ~5b~

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properties of the toner used in development of a la~en~ elec-torstatic image formed on said layer; the techniques (if any) used to discourage accumulation of residual toner on the imaging layer; and the relative efficiency of the cleaning means provided for removal of residual toner from the imaging layer.
The photoconductive imaging layer of the electro-. _ ... . . .. . . . . . .
statographic imaging member can comprise an organic photocon-ductive polymeric material or a photoconductive binder system wherein photoconductive molecules or particles are dispersed through out a film forming insulating resin. Typical of the organic polymer - whose triboelectric properties can be tailored by the incorporation therein of a fluorinated resin include the polyvinylcarbazole polyvinyl pyrene, anthracenic polymers and the charge transfer complexes thereof. The above photoconductive binder systems can compri~@ one or more distinc~ types of photoconductive particle dispersed in one or more film forming insulating resins. Repre-sentative of the inorganic photoconductive particles which are suitable for use in such binder systems include sul~ur, selenium, zinc sulfide, zinc oxide, zinc dadmium sulfide, zinc magnesium oxide, cadmium selenide, zinc silicate, calcium strontium sul-fide, cadmium sulfide, mercuric iodide, mercuric oxide, mercuric - sulfide, indium trisulfide, gallium sele~ide, arsenic disulfide, -G arsenic trisulfide, a~senic triselenide, anti-mony trisulfide, cadmium sulfo-selenide, and mixtures thereof.
- organic photoconductive materials suitab~e for use in such binder layers include: quinacridone pi~ents; phthalocyanine pigments; triphenylamine; 2,4-bis~4,4'-diethylamino-phenyl)-1,3,4-oxadiazol; N-isopropylcarbazole; t~iphenylpyrrol; 4,5-diphenylimidazolidinone; 4,5-diphenylimi~azolidinethione;
- 4,5-bis-(~'-amino-phenyl)-imidazo idion~
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1,5-dicyanonapthalene; 1,4-dicyanonapthalene; aminophthalodinitrile;
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G ~ prLha~}R~}i~; 1,2,5,6-tetra~zacyclooctatetraene-(2,4,6,8,);'

2-mercaptobenzothiazole-2-phenyl-4-diphenylideneoxazolone; 6-hydroxy~
2,3-di(p-methoxy-phenyl)-benzofurane; 4-dimethylamino-benzylidene-kenzhy~razide; 3-benzylidene; am,inocarbazole; poly-N-vinylcarbazole;
(2-nitro-benzylidene)-p-bromoaniline; 2,4-diphenyl-quinazoline; 1, 2,4-triazine; 1,5-diphenyl-3-methyl-pyrazoline; 2-(4'-dimethylamine i phenyl)-benzoxazole; 3-amino-carbazole; and mixtures thereof.
The film forming insulating resin used in the dispersal of the above photoconductive materials can be any of the common -~~ -~ thermoset or thermoplastic materials commonly used with such photo-conductive pigments. Typical of such materials'are epoxy resins, polyvinylchloride, polyvinylacetates, polystyrene, polystyrene-polybutadiene copolymers, polymethacrylate, polyacrylics, poly-acrylonitriles, silicone resins, chlorinated rubbers, phenoxy resins, phenolics, epoxy-phenolic copolymers, epoxy urea form-aldehyde copolymers, epoxy-melamine-formaldehyde resins, polycarbon-ates, polyurethanes, polyamides, saturated polyesters, unsaturated polyesters cross-linked with vinyl monomers and mixtures thereof.
The fluorinated resins used to modify the triboelectric properties of the imaging layer of an electrostatographic imaging member can be any of a number of fluorinated polymer resins ~ -which upon additlon to an imagingllayer are capable of effecting some modification in the triboelectric properties of said layer; t the extent of such modification being dependent upon the relative concentration oi the ~luorinated resin in the imaging layer, and the relative triboelectric properties of said resin. These resins will generally be present in the photoconductive imaging layer in amounts ranging anywhere from about 1 to about 50 weight percent ~ ~ and preferably at/concentration in the range of from about 5-25 weight percent; the preferred concentrat1on generally being determined by empirical testing.

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Representative of the preferred fluorinated resins suitable for use in the method of this.invention include fluorine-modified epoxy resins, fluorine-modified alkyd resins, fluorine-modified polyester resins, fluorine-modified melamine resins, fluorine-modified acrylic resins, fluorinated diol polyesters (described in U. S. Patent 3,240,800), fluorochemical modified urethanes comprising fluoro-aliphatic acid condensates modified acrylate . and methacrylate esters and their copolymers (described in U.
_ S. Patent 2,803,615). Many other well-known fluorinated resins may also be employed in the method of the present invention including, fluoro-azirine polymers and copolymers (described in U.S. Patent 3,255,157); perfluoroalkyl-trifluoromethacrylate copolymers (described in Belgain Patent 685,486), fluorocarbon polyethers, (described in U.S. patent 3,358,003); polymers 15 derived from fluoro ketones, described by A. G. Pittman et al, in J. PolYmer Sci.ence A-l, Volume 4 at pages -- 26, 37 - 47, 1966, and ibid, Volume 6, 1729 - 40, 1968; and other fluorine containing polymers such as, for example, fluorinated vinyl . polymers, condensation polymers, and styrene polymers as des-cribed by W. Postelnek et al, in Fortschritte der HochpolYmeren Forschunq, Volume 1, at pages 75 - 113, 1958.
In addition to their ability to modify the triboelectric properties of the photoconductive imaging layer, many of the preferred fluorinated resins also impart other favorable prop-25 erties to such layers.
For example, many of these preferred fluoro-resins have depressed surface energies thus further facilitating transfer and cleaning of toner particles from the surface of the imaging layer. .
In addition, these materials are relatively insensitive to .. . ... ... . . . ...

changes in ambient humidity and e~hibit good stability under oxidative conditions.
The fluorinated polymers useful in the method of this invention are distinct from the better known fluorocarbon resins 5 B such as polyvinylidene fluoride (commonly referred to as "Kynar" or "Tedlar") with regard to their relatively good compatibility with their non-fluorinated polymeric analogs. They can, therefore, be more readily incorporated into the imaging layer of an electrostato-graphic imaging member without adversely effecting either its mechanical or electrical properties. Some of the fluorinated polymers useful in this method are capable of crosslinking with themselves and with the other resins in the imaging layer, thus, enhancing the mechanical properties (e.g. hardness, abrasi~n resistence, etc.) of such imaging layers.
Electrostatographic imaglng members equipped with the triboelectrically modified imaging layers of this invention can be prepared by forming a substantially uniform coating from a composition containing the above materials in their appropriate - relative proportions on a suitable conductive substrate. With respect to imaging members provided with an imaging layer com- !
prising an organic photoconductive polymeric material, the tribo-electric modifying fluorinated resin is merely added to a fluid vehicle containing the polymeric material and resulting solution sprayed, draw down or dip coated on a con~uctive substrate.
Similar procedures are followed in prepara~ion of photoconductive binder layer systems. Sufficient photoconductive composition must be applied to the conductive substrate so as to provide said substrate with a substantially uniform coating having a dry film thickness in the range of from about 1-50 microns, and preferably of a thickness in the range of from about 5-25 microns.
The conductive substrates upon which such composition is applied can be any of those commonly used in electrophotography: among .' .
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those which are typical include stainless steel, aluminum, chromium, tin-oxide coated or carbon-binder coated glass and an aluminized or conductive resin treated polyethylene-terephthalate film. After application of the photoconduc-tive composition to the conductive substrate, the imaging layer is allowed to cure or dry until substantially free of residual solvents. This process can be accelerated by insertion of the coated substrate into a vacuum oven for a relatively brief period (generally less than 24 hours).
After preparation of the triboelectrically modified electrostatographic imaging member, its triboelectric proper-ties are evaluated on a device of the type depicted in Figure 1. In Figure 1 is shown a triboelectrically modified `
imaging member 1 comprising a triboelectrically modified imaging layer 2 on a conductive substrate 3. As the grounded, rotating fiber brush 4 sweeps the triboelectrically modified imaging member, it sets up a triboelectric current which can be detected on monitoring unit 5. The triboelectrically modified imaging layer is sufficiently conductive to permit passage of such currents from the surface of the imaging layer to the recording device. In this manner, it is possible i to evaluate a variety of triboelectrically modified imaging members and c~pare their triboelectric properties with those of commercially available photoconductive imaging members. ;~
The triboelectrically modified imaging members prepared as described above can be used in anyone of a variety of electrostatographic imaging processes. In such processes, the surface of the triboelectrically modified imaging layer is first sensitized by application of a substantially uniform electrostatic charge to its surface.
Anyone of a variety of well-known techiques can be used to --10-- , impart this electrostatic charge to the imaging member;
those methods generally resorted to include sensitization with a corona electrode, or frictional charging with a ` -fiber brush or web. After the imaging surface of the electro-statographic imaging member has been sensitized, a latent image is formed thereon by selective exposure of this sen-sitized layer to activating electromagnetic energy whereby the charge is selectively dissipated in the light struck regions of the film, thus forming a latent electrostato-graphic image.
The latent image so formed can be rendered visible by development with colored electroscopic toner particles.
Such development may take place directly on the imaging member or the latent image can be transferred to a receiving sheet and developed thereon. Once the latent image has ;
been developed, it can be permanently affixed to the photocon-ductor surface or the receiving sheet by solvent or thermal fusion techniques. Generally, where the electrostatogra-phic imaging member is to be reused in a cyclic imaging system, the developed image is transferred to a receiving sheet prior to fixation. After transfer of the developed tcner image, the imaging layer of the electrostatographic imaging member is cleaned of residual toner particles prior to reuse in a second copying cycle. This is generally achieved by applying a neutralizing charge to the imaging ;
layer followed by mechanical removal of residual toner remaining on the imaging surface.
The Examples which follow further define, describe and illustrate preparation, use and evaluation of the tribo-electrically modified electrostatographic imaging members ofthis invention. Conditions and apparatus not specifically set forth in following specific embodiments of this invention --11-- :

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are presumed to be standard or as hereinbefore described.
Parts and percentages appearing in such examples are by `!
weight unless otherwise indicated. :
EXAMPLE I
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In order to provide a standard against which the triboelectrically modified electrostatographic imaging members of this invention can be compared, a conventional xerographic plate .~

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having an amorphous seleniùm imaging layer is evaluated on the device illustrated in Fig. 1. The rotating brush used in this and all subsequent evaluations c.omprises bleached and scoured No. 5 denier rayon flat fibers having a fiber length of about 5/8 inches and a fiber density of about 35,000 fibers per square inch. These fibers, which are set in a conductive grounded cylindrical backing approximately 3 1/2 inches in diameter, sweep the imaging layer of the electrostatographic imaging member at a ~- ~~~~ rotational speed of 2.6 revolutions per second with an interfer-ence of about 0.10 inches. Such evaluation is carried out under ambient conditions (35 to 45% relative humidity and 72-75F).
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The sign convention adopted for this evaluation is such that a - - - positive current flowing from the brush to the plate is designated as triboelectrically "positive". ThUs, a material which is more triboelectrically pcsitive than the rayon brush will draw a pos- `
itive current and vice versa.
The selenium based photoconductor (Xerox Type "E~ flat plate) evaluated by this proceæure exhibits a negative tribo-current of about 0.6-0.7 x 10-1 amperes. This value is apparently independant of the thickness of the selenium imaging layer. A
second imaging member having an imlaging layer comprising a metal-free phthaiocyanine pigment(as disclosed ln U.S. Re 27,117) in an epoxy binder - 1:11 weight ratio pigment to binder - is evaluated under identical conditions and exhibits a positive tribocurrent ~5 of about 37 x 10-1 amperes. Because of this sharp disparity between the tribocurrents of these two dissimilar imaging members, it comes as no surprise that the same development and cleaning system which operate efficiently with selenium photoreceptors produce toner filming on the surface of a phthalocyanine binder layer.

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6~i In evaluation of some of the electrostatographic imaging members of this invention, it may be necessary to postpone such evaluation until the imaging layer is "broken in". The initial action of the rayon brush against the plate may resuit in a "buffing" of the plate which can influence the triboelectric response. Such a buffing effect when present often manifests itself as a variation in the current generated and/or a change in sign of the current dur- `
ing the first serveral seconds when the brush sweeps the surface of the imaging layer. In the event that this buffing is observed, the plate should be rested for several hours -;
prior to reattempting such evaluation. Subsequent to this period of ~uiescence, the tribocurrent of the buffed plate should be fairly constant upon triboelectrification with ~
the rayon brush. ~ -EXAMPLES II - ~
A series of photoconductive binder layers are -prepared from a photoconductive pigment and a mixed resinous ~`
binder. Such plates are prepared by dispersing the appropriate ~;
relative concentration of photoconductive pigment and binder ~
in 400 parts by weight Ethyl Cellosolve (trade mark for -ethylene glycol monoethyl ether) and draw coating the resulting slurry on scrubbed aluminum plates. After this photoconductive composition is applied to the aluminum sub-strate, the imaging member is cured by heating in a vacuum oven at 16-0C for a period of 16 hours. Sufficient photo-conductive composition is applied to the substrate so as to provide an imaging layer having a dry film thickness of from about 8 to about lO microns. The table which follows ;~
illustrates the shift in tribocurrent with increasing concen-trations of fluorinated epoxy resins.
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6'~ ., Binder Composition Photoconductive Pi~ent Example *Epoxy **Fluoro- X-Form of Tribo No. Phenolic Epoxy Metal-Free Current Resin Resin, Phthalo- (in uni~s (qm) (qm) _ cyanine (~m) of 10-1~ amps) I 20.0 0.0 - 2.0 +37 II 21.5 0.5 2.0 ~26 III 21.0 1.0 2.0 +30 IV 20.5 1.5 2.0 +10 V 20.25 1.72 2.0 -15 VI 20.0 2.0 2.0 4 VII 17.75 2.25 2.0 -26 VIII 1935 2.5 2.0 -22 ''B' ' *Epoxy phenolic resin is~a mixture of 355 parts by weight epoxy resin (Epon ~&07 - available from Shell Chemical Co. - 100% solids content); 200 parts by weight phenolic resin (Resyn ~201 - Resyn Corporation - 75% solids content); and 4~ parts by weight urea formaldehyde resin (uformite ~ -240-Rohm and Haas Inc. - 60% solids content).
- **Fluoro - Epoxy resin is a highly fluorinated epoxy resin available from 3M - solids content 100%, - elemental fluorine present 22 weight percent -this resin is believed to be the same as that described in U.S. Patent 3,255,131.
It is apparent from the above table that as the concentration of epoxy phenolic resin is progressively displaced by the substitution of a fluorinated epoxy resin, the tribo-- ----- electric properties of the plate become increasingly negative, thus, approaching the triboelectric properties of amorphous selenium (tribocurrent of 0.6 x 10-~ amps) Fig. 2 is a gra~phical illustration of this shift in the triboelectric properties of p~thalocyanine binder plates. As the percent of fluorinated epoxy resin in the binder increases to in excess of about 20 weight percent, the phthalocyanine binder plates assume tribo-electric properties which approximate the triboelectric properties of amorphous selenium.
EXAMPLES IX - XVI
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The procedures of Examples II - VIII are used with analogous materials, to illustrate the generality of the concept.
The photoconductor is 2,5 bis-(p-diethyl aminophenyl) 1, 3, ~

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oxadiazole , as disclosed in Neugebauer et al, U.S. 3,189,447.
The non-fluorinated binder is an acrylic (Lucite* 2046, ~
Du Pont, a copolymer of equal parts of _- and i butyl -methacrylates). The fluorinated binder is a polymer of per-fluoro methyl methacrylate. The results of tribo measurements on these coatings are analogous to those in Examples I - VIII: -as the fraction of fluorinated polymer is increased, the measured triboelectric charging current progressively shifts from highly positive to strongly negative values. An optimal composition may, accordingly, be selected to match the properties desired of the photoreceptor. In the case of matching the properties of selenium with this particular charging device, an optimal value would be close to zero~
EXAMPLES XVII - XXII
The experiments of Examples IX - XVI are repeated, using as photoconductive pigment Quindo*Magenta, a quina~
cridone of the type generally disclosed by Tulagin in U.S. 3,667,945. The mixture of normal and fluoro modified acrylic polymers in those examples is replaced with a series of copolymers of ~ .
n (2 n+l) CH2 0 - C - C = CH2 and C~3 `;
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n (2 n+l) CH2 - 0 - C - C = CH2 of the type described in Belgain Patent 685486 (Geigy, A.G.).
Again, it is found that as the percentage of fluoro modified polymer increases, the tribo current shifts progressively towards the negative side. This example demonstrates that copolymers of normal and fluoro-modified monomers ~ay be used in place of polymer blends of analogous compositions to achieve the objectives of the invention.
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EXAMPLE XXI;II - XXIV
The procedures of Example II - VIII are repeated except for the substitution of the following photoconductive materials for the X-form of metal-free phthalocyanine ~`
pigment. In each case the concentration of photoconductor is adjusted for optimal performance. Ordinarily, the relative concentration of pigment to binder will range from about 3 to about 50 volume percent.
Photoconductor XXV Trigonal selenium pigment XXVI Triphenyl amine XXVII Cadmium sulfide XXVIII Poly(N-vinylcarbazole) particles EXAMPLE XXV
The phthalocyanine binder plate of Example I is sensitized in the dark by charging with a corona electrode -to a negative potential of about 600 volts. This sensitized member is then selectively exposed to a light and shadow image and then the latent image thus produced rendered visible by development with colored electroscopic toner par-ticles specifically formulated for use with amorphous selenium photoreceptors. Toner transfer and cleaning are performed ,~ r `
with systems also engineered for use with amorphous selenium.
After a few copying cycles, toner residues are seen to accumulate on the imaging surface of the imaging member and copy quality begins to deteroriate. ;~
EXAMPLE XXVI
The electrostatographic imaging member prepared as described in Example VIII is sensitized in the dark by charging with a corona electrode to a negative potential of about 600 volts. This sensitized member is then selectively exposed to a light ahd shadow image and the latent image thus ;

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produced rendered visible by development with the same type .
of electroscopic toner particles used in Example XXV. Toner transfer and cleaning are also performed by the same systems .~ .
used in Example ''' ~.

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. ~n~. copy quality is superior to that experienced in Example )(~1/ , .
and no toner residue is seen to accumulate on the imaging surface of the imaging member during an equivalent number of copying cycles.
The concepts of the invention may be applied equally to nonphotoconductive dielectric coatings, such as those used for electrographic recording, TESI imaging, and the like.
Generally, the charging characteristic of cast films may be adjusted by the measured addition of phase compatible fluoro polymers to nonfluorinated polymers. Other extensions of this concept will be apparent to those skilled in the art.

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Claims (21)

WHAT IS CLAIMED IS:

1. A method for modifying the triboelectric prop-erties of the photoconductive imaging layer of an electro-statograhic imaging member comprising incorporating into said layer a triboelectric modifying effective amount of a phase compatible fluorinated resin other than a fluorocarbon resin.

2. The method of Claim 1, wherein said fluorinated resin is selected from the group consisiting of epoxy resins, alkyd resins, polyester resins, melamine resins, acrylic resins, and mixtures thereof.

3. The method of Claim 1, wherein the photoconductive imaging layer comprises a photoconductive pigment disposed in a film forming insulating resin.

4. The method of Claim 1, wherein the photoconductive component of the triboelectrically modified photoconductive imaging layer comprises particles of selenium, zinc oxide, cadmium sulfide, arsenic triselenide, poly-N-vinylcarbazole, phthalocyanine pigments, and mixtures thereof.

5. The method of Claim 1, wherein the photoconductive imaging layer comprises an organic photoconductive polymeric material.

6. The method of Claim 1, wherein the photoconductive imaging layer contains from about 1 to about 50 weight per-cent fluorinated resin.

7. The method of Claim 1, wherein the photoconductive imaging layer contains from about 5 - 25 weight percent fluorinated resin.

8. A triboelectrically modified electrostatographic imaging member comprising a conductive substrate having operatively disposed in relation to at least one surface thereof a triboelectrically modified photoconductive imagine layer having a dry film thickness of from about 1-50 microns and having incorporated therein a triboelectric modifying effective amount of a phase compatible fluorinated resin other than a fluorocarbon resin.

9. The imaging member of Claim 8, wherein said fluorinated resin is selected from the group consisting of epoxy resins, alkyd resins, polyester resins, melamine resins, and mixtures thereof.

10. The imaging member of Claim 8, wherein the photo-conductive imaging layer comprises a photoconductive pigment disposed in a film forming insulating resin.

11. The imaging member of Claim 8, wherein the photocon-ductive component of the triboelectrically modified photocon-ductive imaging layer comprises particles of selenium, zinc oxide, cadmium sulfide, arsenic triselenide, polyvinylcarbazole, phthalocyanine pigments, and mixtures thereof.

12. The imaging member of Claim 8, wherein the photo-conductive imaging layer comprises an organic photoconduc-tive polymeric material.

13. The imaging member of Claim 11, wherein the photo-conductive imaging layer contains from about 1 to about 50 weight percent fluorinated resin.

14. The imaging member of Claim 12, wherein the photo-conductive imaging layer contains from about 5 - 25 weight percent fluorinated resin.

15. An electrostatographic imaging process comprising:
(a) providing a triboelectrically modified imaging member comprising a conductive substrate having operatively disposed in relation to at least one surface thereof a tribo-electrically modified photoconductive imaging layer having a dry film thickness of from about 1-50 microns and having incorporated therein a triboelectric modifying effective amount of a phase compatible fluorinated resin; other than a fluorocarbon resin and (b) forming a latent electrostatic image on the imaging surface of the triboelectrically modified photo-conductive imaging layer.

16. The process of Claim 15, wherein said fluorinated resin is sleceted from the group consisting of epoxy resins, alkyd resins, polyester resins, melamine resins, acrylic resins, and mixtures thereof.

17. The process of Claim 15, wherein the photoconduc-tive imaging layer comprises a photoconductive pigment disposed in a film forming insulated resin.

18. The process of Claim 15, wherein the photoconduc-tive component of the triboelectrically modified photoconduc-tive imaging layer comprises particles of selenium, zinc oxide, cadmium sulfide, arsenic triselenide, poly-N-vinyl-carbazole phthalocyanine pigments, and mixtures thereof.

19. The process of Claim 15, wherein the photocon-ductive imaging layer comprises an organic photoconductive polymeric material.

20. The process of Claim 15, wherein the photoconduc-tive imaging layer contains from about 1 to about 50 weight percent fluorinated resin.

21. The process of Claim 15, wherein the photocon-ductive imaging layer contains from about 5 - 25 weight.
percent fluorinated resin.