US3850632A - Electrophotographic photosensitive plate - Google Patents

Electrophotographic photosensitive plate Download PDF

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US3850632A
US3850632A US00275212A US27521272A US3850632A US 3850632 A US3850632 A US 3850632A US 00275212 A US00275212 A US 00275212A US 27521272 A US27521272 A US 27521272A US 3850632 A US3850632 A US 3850632A
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percent
cellulose
weight
photosensitive plate
layer
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US00275212A
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M Hukase
M Tomono
S Inowa
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Konica Minolta Inc
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Konica Minolta Inc
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/14—Inert intermediate or cover layers for charge-receiving layers
    • G03G5/147—Cover layers
    • G03G5/14708—Cover layers comprising organic material
    • G03G5/14713—Macromolecular material
    • G03G5/14717—Macromolecular material obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • G03G5/1473—Polyvinylalcohol, polyallylalcohol; Derivatives thereof, e.g. polyvinylesters, polyvinylethers, polyvinylamines
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/14—Inert intermediate or cover layers for charge-receiving layers
    • G03G5/147—Cover layers
    • G03G5/14708—Cover layers comprising organic material
    • G03G5/14713—Macromolecular material
    • G03G5/14747—Macromolecular material obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • G03G5/14782—Cellulose and derivatives

Definitions

  • ABSTRACT Electrophotographic photosensitive plate of improved moisture fastness having on its photoconductive layer a protective coating comprising polyvinyl butyral and a cellulose derivative which provides the plate with protection from abrasion and deterioration in resolving power under either high or low humidity conditrons.
  • This invention relates to an electrophotographic pho-
  • the conventional electrophotographic process is carried out in such a manner that a photosensitive plate, prepared by forming a photoconductive layer on an electroconductive support, is positively or negatively charged (according to the characteristics of the photosensitive plate) by means of corona discharge, and then exposed to electromagnetic waves, e.g. light or X-ray, to form a latent electrostatic image by utilization of the photoconductivity of the photosensitive plate.
  • This latent image is developed with a toner which has been charged with a polarity opposite to that of said latent image, and, if the developed image is carried on the photosensitive layer (this means that the photosensitive layer serves as a recording layer as in the Electrofax process), this is fixed as is by application of heat or solvent vapors, while if the recording layer is used separately from the photosensitive layer (as in the Xerox system using a selenium photosensitive plate or the like), the developed toner image is transferred, according to the electrostatic image transfer process, to a recording layer, ordinarily on a separate paper, and is then fixed. After the fixing, the photosensitive plate is subjected to cleaning and is reused.
  • a single photosensitive plate is subjected to a copying cycle comprising charging, imagewise exposure, toner development and fixing optionally with image transfer, repeatedly, as often several thousand times.
  • the present invention is concerned with an improvement of the photosensitive plate to be used in the latter process.
  • Photosensitive plates used in the latter process are abraded or injured during cleaning. transfer, and the like mechanical operations. Such troubles become fatal drawbacks for the photosensitive plates. Particularly in xeroradiography, relatively many operations are effected manually, so that such troubles as mentioned above tend to take place.
  • the coating should not react with the photoconductive substance used.
  • the coating should adhere well to the photoconductive layer.
  • the heat treatment for forming the protective coating should not be effected over a long period of time when the heating temperature isabove 40C.
  • the coating should not'have an electric conductivity in the horizontal direction so as not to degrade the photosensitive plate in contrast or resolving power.
  • the coating should not have a volume electric resistivity of more than 10 cm, because in winter, when the air is dry, the photosensitive plate is deteriorated in resolving power due to high electric resistance.
  • the coating should be excellent in abrasion resistance.
  • the coating should have such a thickness as not to deteriorate the photosensitive plate in resolving power and abrasion resistance.
  • the coating should be excellent in moisture fastness.
  • the protective coatings disclosed in the aforesaid prior art literature are composed of polystyrene, polycarbonate, polyvinyl formal, polyvinyl acetal, cellulose acetate, etc. which heretofore have not been satisfactory.
  • these known protective coatings are relatively satisfactory in abrasion resistance, they are low in moisture fastness and hence cannot be used throughout the year, including summer, when the temperature and humidity are high and winter when the temperature and humidity are low.
  • the present invention provides a novel protective coating which has overcome the drawbacks of the conventionally known protective coatings. That is, the present invention is concerned with an electrophotographic photosensitive plate prepared by using, as a support, a metal such as aluminum, zinc, brass or copper, or an electroconductive glass, forming, on said electroconductive support, a photoconductive layer composed of selenium, selenium-tellurium or the like selenium alloy, zinc oxide, lead oxide or cadmium sulfide. and further forming on said photoconductive layer a protective layer comprising a mixture of polyvinyl butyral and a cellulose derivative which is compatible with the polyvinyl butyral and which itself has a low volume resistivity.
  • Polyvinyl butyral having a butyralation degree'within the range of 57 to 65 mole percent gives particularly favorable results.
  • suitable cellulose derivatives include ethyl cellulose, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose acetobutyrate and cellulose nitrate.
  • the proportion of the above-mentioned cellulose derivative based on the amount of polyvinyl butyral is, for example, 20 to 50 percent by weight in the case of cellulose nitrate, 10 to 30 percent by weight in the case of cellulose diacetate, 20 to 28 percent by weight in the case of cellulose triacetate, and 10 to 30 percent by weight in the case of cellulose acetobutyrate.
  • the proportion of the cellulose derivative used is not fixed but varies depending on the nature of the cellulose derivative employed.
  • the protective layer In forming the protective layer according to the present invention, a mixture of the above-mentioned two components is dissolved in dioxane or the like organic solvent therefor and then coated on the photoconductive layer of the photosensitive plate.
  • the said mixture When it is desired to form the protective layer by a dipping method, the said mixture may be dissolved in a proportion of 3 to 4 g. per I00 cc. of the solvent.
  • the protective coating is made thicker, the photosensitive plate is deteriorated in resolving power and
  • a protective layer-forming solution identical in composition with that used in the dipping method is coated by means ofa whirler, innumerable radial wrinkles are formed on the resulting protective layer. If, in;
  • ethyl cellulose more than 3 percent by weight of ethyl cellulose is incorporated into said solution, the resulting protective layer will be free of radial wrinkles and will provide a uniform surface.
  • an ethyl cellulose content of about 3 to 8 percent by weight is preferred.
  • the photosensitive plate of the present invention not only has a high resolving power under high humidity conditions but also is greatly improved in image characteristics even under low humidity conditions, and thus is high in resolving power and excellent in resistance to abrasion and injury.
  • the photosensitive plate of the present invention is 3 to 4 times higher in abrasion resistance than a photosensitive plate having a protective coating composed of only the cellulose derivative.
  • a photosensitive plate having a protective coating composed of only the cellulose derivative is deteriorated in resolving power under high humidity conditions, whereas the photosensitive plate of the present invention shows a high resolving power at a humidity within the range of from 30 to 90 percent.
  • a resolving power of at least tl to lq lings per mm. is necessary.
  • Photosensitive selenium plates-having protective layers wherein polyvinyl butyral andtypical cellulose derivatives were singly used, were tested in resolving power under various humidity conditions.
  • the results obtained were as set forth in Table l, in which the values of resolving power are represented by lines per mm.
  • Table 1 useful. This, however, is not practical because adsorption of water and absorption of moisture would be increased under high humidity conditions.
  • the present invention provides a protective layer which can be rendered free of the drawbacks of conventionally known protective layers. It is very surprising that the drawbacks encountered when a polyvinyl butyral or a cellulose derivative is used alone by itself can be removed by the joint use of these two.
  • Example 1 3 grams of a mixture constituting a protective coating composition comprising percent by weight of polyvinyl butyral (Eslec BM-2 produced by Sekisui Chemical Co.) and 30 percent byweight of cellulose nitrate (FQ produced by Daicel Co.) was dissolved in 100 cc. of dioxane. The resulting solution was'coated in accor dance with a conventional dipping method on a photosensitive selenium plate to a thickness of about l u, whereby the photosensitive plate showed an excellent abrasion resistance and a high resolving power of 8 to 10 lines per mm. at a humidity within the range from 30 to 90 percent.
  • a protective coating composition comprising percent by weight of polyvinyl butyral (Eslec BM-2 produced by Sekisui Chemical Co.) and 30 percent byweight of cellulose nitrate (FQ produced by Daicel Co.) was dissolved in 100 cc. of dioxane. The resulting solution was
  • Example 2 3 grams of a mixture comprising percent by weight of polyvinyl butyral (Eslec BM-2 produced by Sekisui Chemical Co.) and 25 percent by weight of cellulose diacetate (L-AC produced by Daicel Co.) was dissolved in 100 cc. of dioxane. The resulting solution was coated in accordance with a conventional dipping 'method on a photosensitive selenium plate to a thickness of about 1 .1., whereby the photosensitive plate showed the same characteristics as in Example 1.
  • Eslec BM-2 polyvinyl butyral
  • L-AC cellulose diacetate
  • Example 3 4 grams of a mixture comprising 75 percent by weight of polyvinyl butyral (Eslec BM-2 produced by Type of protective coating Resolving Power at the given humidity on selenium 38% 57% 68% 8l% Not-protected 12.5 12.5 l0- l0- l0 12.5 12.5 (Butyralation (Residual acetyl degree, mole%) content, mole%) Polyvinyl butyral 57 :l: 3 Less than 3 5.0 8-10 8-l0 8-l0 8.0 do. 62 t 3 do. 4.0- 8-10 8-l0 S-lO 8.0
  • Example 4 3 grams of a resin mixture comprising 80 percent by weight of polyvinyl butyral (Eslec BM-2 produced by Sekisui Chemical Co.) and percent by weight of cellulose acetobutyrate (Kodapak lI produced by Eastman Kodak Co.) was dissolved in 100 cc. of dioxane. The resulting solution was coated in accordance with a conventional dipping method on a photosensitive selenium plate to a thickness of about l ,u, whereby the photosensitive plate showed the same characteristics as in Example 1.
  • Example 5 characteristics as in Example I.
  • Example 6 3 grams of a resin mixture comprising 65 percent by weight of polyvinyl butyral (Eslec BM-Z produced by Sckisui Chemical Co.) and 35 percent by weight of cellulose nitrate (FO produced by Daicel Co.) was dissolved in 100 cc. of dioxane. The resulting solution was coated onto a 40 .1. thick photosensitive CdS plate to a thickness of about 0.5 ;1., whereby the photosensitive plate showed the same characteristics as in Example I.
  • Eslec BM-Z produced by Sckisui Chemical Co.
  • FO cellulose nitrate
  • An electrophotographic photosensitive plate comprising an electroconductive layer, a photoconductive layer thereon, and a protective polymer coating layer on the opposite surface of said photoconductive layer, said protective coating having a thickness not greater than one micron and comprising polyvinyl butyral having a butyralation degree of 57 to 65 mole percent and a cellulose derivative selected from the group consisting of cellulose diacetate. cellulose triacetate.
  • cellulose propionate, cellulose acetobutyrate, and cellulose nitrate said polyvinyl butyral being present in said coating in an amount varying from 50 to 90 percent by weight, and said cellulose derivative being present in said coating in an amount ranging from 10 to 50 percent, by weight, said protective polymer coating layer having a volume resistivity no greater than 10 ohm- 2.
  • An electrophotographic photosensitive plate which comprises, on a support of an inorganic material selected from the group consisting of aluminum, zinc, brass, copper, and electroconductive glass, :1 photoconductive layer made of a substance selected from the group consisting of selenium, selenium-tellurium, zinc oxide, lead oxide and cadmium sulfide and a protective polymer coating layer coated on the opposite surface of said photoconductive layer, said protective coating having a thickness not greater than one micron and comprising a polyvinyl butyral having a butyralation degree of 57 to 65 mole percent and a cellulose derivative compatible with said polyvinyl butyral, said polyvinyl butyral being present in said coating in an amount varying from 50 to percent, by weight, and said cellulose derivative being present in said coating in an amount ranging from l0 to 50 percent, by weight, said protective'polymer coating layer having a volume resistivity no greater than 10 ohm cm.
  • An electrophtograp'hic photosensitive plate as claimed in claiml wherein said protective polymer coating layer also contains 3 to 8 percent of ethyl cellulose.

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  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • General Physics & Mathematics (AREA)
  • Photoreceptors In Electrophotography (AREA)

Abstract

Electrophotographic photosensitive plate of improved moisture fastness having on its photoconductive layer a protective coating comprising polyvinyl butyral and a cellulose derivative which provides the plate with protection from abrasion and deterioration in resolving power under either high or low humidity conditions.

Description

United States Patent 91 Hukase et al.
[ 51 Nov. 26, 1974 ELECTROPHOTOGRAPHIC PHOTOSENSITIVE PLATE Inventors: Masahiro Hukase; Makoto Tomono;
Sigero Inowa, all of Tokyo, Japan Foreign Application Priority Data July 26, 1971 Japan 46-55877 US. Cl 96/l.8, 96/l.5, 117/218 Int. Cl. 603g 5/00, G03g 5/02 Field of Search 96/1.5, 1.8; 117/215, 218
References Cited UNITED STATES PATENTS 8/1957 Ullrich 96/l.5 X 11/1958 Daubner 117/17.5 X
3,127,331 3/1964 Neber 96/1.5 X
3,140,174 7/1964 Clark 96/1.8 X
3,170,790 2/1965 Clark 96/l.5 X
3,355,289 11/1967 Hall et al. 96/1.5 X
3,434,832 3/1969 Joseph et al. 96/1.5
3,652,268 3/1972 Rowe i i. 96/1.5 3,761,259 9/1973 Arai et a1 117/218 X Primary Examiner-David Klein Assistant ExaminerJohn R. Miller Attorney, Agent, or FirmWaters, Roditi, Schwartz, & Nissen [57] ABSTRACT Electrophotographic photosensitive plate of improved moisture fastness having on its photoconductive layer a protective coating comprising polyvinyl butyral and a cellulose derivative which provides the plate with protection from abrasion and deterioration in resolving power under either high or low humidity conditrons.
6 Claims, N0 Drawings Dessauer et al. 96/1.5 X
ELECTROPHOTOGRAPHIC PHOTQSENSITIVE PLATE This invention relates to an electrophotographic pho- In general, the conventional electrophotographic process is carried out in such a manner that a photosensitive plate, prepared by forming a photoconductive layer on an electroconductive support, is positively or negatively charged (according to the characteristics of the photosensitive plate) by means of corona discharge, and then exposed to electromagnetic waves, e.g. light or X-ray, to form a latent electrostatic image by utilization of the photoconductivity of the photosensitive plate. This latent image is developed with a toner which has been charged with a polarity opposite to that of said latent image, and, if the developed image is carried on the photosensitive layer (this means that the photosensitive layer serves as a recording layer as in the Electrofax process), this is fixed as is by application of heat or solvent vapors, while if the recording layer is used separately from the photosensitive layer (as in the Xerox system using a selenium photosensitive plate or the like), the developed toner image is transferred, according to the electrostatic image transfer process, to a recording layer, ordinarily on a separate paper, and is then fixed. After the fixing, the photosensitive plate is subjected to cleaning and is reused. Thus, a single photosensitive plate is subjected to a copying cycle comprising charging, imagewise exposure, toner development and fixing optionally with image transfer, repeatedly, as often several thousand times.
The present invention is concerned with an improvement of the photosensitive plate to be used in the latter process.
Photosensitive plates used in the latter process are abraded or injured during cleaning. transfer, and the like mechanical operations. Such troubles become fatal drawbacks for the photosensitive plates. Particularly in xeroradiography, relatively many operations are effected manually, so that such troubles as mentioned above tend to take place.
Among photosensitive layers, the photoconductive However, the protective coating should, of course,
not deprive the photosensitive plate of its inherent characteristics, and should satisfy such conditions as mentioned below.
I. The coating should not react with the photoconductive substance used.
2. The coating should adhere well to the photoconductive layer.
3. In case the photoconductive layer is composed of selenium or its alloy, the heat treatment for forming the protective coating should not be effected over a long period of time when the heating temperature isabove 40C.
4. The coating should not'have an electric conductivity in the horizontal direction so as not to degrade the photosensitive plate in contrast or resolving power.
5. The coating should not have a volume electric resistivity of more than 10 cm, because in winter, when the air is dry, the photosensitive plate is deteriorated in resolving power due to high electric resistance.
6. The coating should be excellent in abrasion resistance.
7. The coating should have such a thickness as not to deteriorate the photosensitive plate in resolving power and abrasion resistance.
8. The coating should be excellent in moisture fastness.
However, the protective coatings disclosed in the aforesaid prior art literature are composed of polystyrene, polycarbonate, polyvinyl formal, polyvinyl acetal, cellulose acetate, etc. which heretofore have not been satisfactory. Although these known protective coatings are relatively satisfactory in abrasion resistance, they are low in moisture fastness and hence cannot be used throughout the year, including summer, when the temperature and humidity are high and winter when the temperature and humidity are low.
The present invention provides a novel protective coating which has overcome the drawbacks of the conventionally known protective coatings. That is, the present invention is concerned with an electrophotographic photosensitive plate prepared by using, as a support, a metal such as aluminum, zinc, brass or copper, or an electroconductive glass, forming, on said electroconductive support, a photoconductive layer composed of selenium, selenium-tellurium or the like selenium alloy, zinc oxide, lead oxide or cadmium sulfide. and further forming on said photoconductive layer a protective layer comprising a mixture of polyvinyl butyral and a cellulose derivative which is compatible with the polyvinyl butyral and which itself has a low volume resistivity.
Polyvinyl butyral having a butyralation degree'within the range of 57 to 65 mole percent gives particularly favorable results. Representative examples of suitable cellulose derivatives include ethyl cellulose, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose acetobutyrate and cellulose nitrate. Satisfactory results are obtainable when the proportion of the above-mentioned cellulose derivative based on the amount of polyvinyl butyral is, for example, 20 to 50 percent by weight in the case of cellulose nitrate, 10 to 30 percent by weight in the case of cellulose diacetate, 20 to 28 percent by weight in the case of cellulose triacetate, and 10 to 30 percent by weight in the case of cellulose acetobutyrate. Thus, the proportion of the cellulose derivative used is not fixed but varies depending on the nature of the cellulose derivative employed.
In forming the protective layer according to the present invention, a mixture of the above-mentioned two components is dissolved in dioxane or the like organic solvent therefor and then coated on the photoconductive layer of the photosensitive plate. When it is desired to form the protective layer by a dipping method, the said mixture may be dissolved in a proportion of 3 to 4 g. per I00 cc. of the solvent.
If the protective coating is made thicker, the photosensitive plate is deteriorated in resolving power and When a protective layer-forming solution identical in composition with that used in the dipping method is coated by means ofa whirler, innumerable radial wrinkles are formed on the resulting protective layer. If, in;
this case, more than 3 percent by weight of ethyl cellulose is incorporated into said solution, the resulting protective layer will be free of radial wrinkles and will provide a uniform surface. However, when the content of ethyl cellulose is excessively high, undesirable results are brought about under conditions of low humidity. Ordinarily, therefore, an ethyl cellulose content of about 3 to 8 percent by weight is preferred.
The photosensitive plate of the present invention not only has a high resolving power under high humidity conditions but also is greatly improved in image characteristics even under low humidity conditions, and thus is high in resolving power and excellent in resistance to abrasion and injury. For example, the photosensitive plate of the present invention is 3 to 4 times higher in abrasion resistance than a photosensitive plate having a protective coating composed of only the cellulose derivative. Furthermore, a photosensitive plate having a protective coating composed of only the cellulose derivative is deteriorated in resolving power under high humidity conditions, whereas the photosensitive plate of the present invention shows a high resolving power at a humidity within the range of from 30 to 90 percent. For obtaining a good image, a resolving power of at least tl to lq lings per mm. is necessary.
Photosensitive selenium plates-having protective layers, wherein polyvinyl butyral andtypical cellulose derivatives were singly used, were tested in resolving power under various humidity conditions. The results obtained were as set forth in Table l, in which the values of resolving power are represented by lines per mm.
Table 1 useful. This, however, is not practical because adsorption of water and absorption of moisture would be increased under high humidity conditions.
As will be understood from Table l, the present invention provides a protective layer which can be rendered free of the drawbacks of conventionally known protective layers. It is very surprising that the drawbacks encountered when a polyvinyl butyral or a cellulose derivative is used alone by itself can be removed by the joint use of these two.
The present invention is illustrated in further detail below with reference to the following representative, non-limiting examples.
Example 1 3 grams ofa mixture constituting a protective coating composition comprising percent by weight of polyvinyl butyral (Eslec BM-2 produced by Sekisui Chemical Co.) and 30 percent byweight of cellulose nitrate (FQ produced by Daicel Co.) was dissolved in 100 cc. of dioxane. The resulting solution was'coated in accor dance with a conventional dipping method on a photosensitive selenium plate to a thickness of about l u, whereby the photosensitive plate showed an excellent abrasion resistance and a high resolving power of 8 to 10 lines per mm. at a humidity within the range from 30 to 90 percent.
Example 2 3 grams of a mixture comprising percent by weight of polyvinyl butyral (Eslec BM-2 produced by Sekisui Chemical Co.) and 25 percent by weight of cellulose diacetate (L-AC produced by Daicel Co.) was dissolved in 100 cc. of dioxane. The resulting solution was coated in accordance with a conventional dipping 'method on a photosensitive selenium plate to a thickness of about 1 .1., whereby the photosensitive plate showed the same characteristics as in Example 1.
Example 3 4 grams of a mixture comprising 75 percent by weight of polyvinyl butyral (Eslec BM-2 produced by Type of protective coating Resolving Power at the given humidity on selenium 38% 57% 68% 8l% Not-protected 12.5 12.5 l0- l0- l0 12.5 12.5 (Butyralation (Residual acetyl degree, mole%) content, mole%) Polyvinyl butyral 57 :l: 3 Less than 3 5.0 8-10 8-l0 8-l0 8.0 do. 62 t 3 do. 4.0- 8-10 8-l0 S-lO 8.0
5.0 More than do. 67 4-6 4.0 8.0 6.3 6.3 5.0 Cellulose 6.0 4.0 2.0 0 0 dlaeetate Cellulose l0.0 8-10 2.0 0
nitrate 60 Sektsui Chemical Co.) and 25 percent by weight of cel- As is clear from Table l, polyvinyl butyrals having a butyralation degree within the range of from 57 to 65 mole percent give favorable results, and those having a butyralation degree of more than 67 mole percent give somewhat inferior results.
For preventing the degradation in resolving power under low humidity conditions, it might be thought that the addition of an ionic surface active agent would be pt, whereby the photosensitive plate showed the same characteristics as in Example 1.
Example 4 3 grams of a resin mixture comprising 80 percent by weight of polyvinyl butyral (Eslec BM-2 produced by Sekisui Chemical Co.) and percent by weight of cellulose acetobutyrate (Kodapak lI produced by Eastman Kodak Co.) was dissolved in 100 cc. of dioxane. The resulting solution was coated in accordance with a conventional dipping method on a photosensitive selenium plate to a thickness of about l ,u, whereby the photosensitive plate showed the same characteristics as in Example 1.
Example 5 characteristics as in Example I.
Example 6 3 grams of a resin mixture comprising 65 percent by weight of polyvinyl butyral (Eslec BM-Z produced by Sckisui Chemical Co.) and 35 percent by weight of cellulose nitrate (FO produced by Daicel Co.) was dissolved in 100 cc. of dioxane. The resulting solution was coated onto a 40 .1. thick photosensitive CdS plate to a thickness of about 0.5 ;1., whereby the photosensitive plate showed the same characteristics as in Example I.
What we claim is:
1. An electrophotographic photosensitive plate, comprising an electroconductive layer, a photoconductive layer thereon, and a protective polymer coating layer on the opposite surface of said photoconductive layer, said protective coating having a thickness not greater than one micron and comprising polyvinyl butyral having a butyralation degree of 57 to 65 mole percent and a cellulose derivative selected from the group consisting of cellulose diacetate. cellulose triacetate. cellulose propionate, cellulose acetobutyrate, and cellulose nitrate, said polyvinyl butyral being present in said coating in an amount varying from 50 to 90 percent by weight, and said cellulose derivative being present in said coating in an amount ranging from 10 to 50 percent, by weight, said protective polymer coating layer having a volume resistivity no greater than 10 ohm- 2. An electrophotographic photosensitive plate as claimed in claim 1, wherein the protective polymer coating layer is composed of 50 to 80 percent by weight of polyvinyl butyral and 20 to 50 percent by weight of cellulose nitrate.
3. An electrophotographic photosensitive plate as claimed in claim 1, wherein the protective polymer coating layer is composed of to 90 percent by weight of polyvinyl butyral and 10 to 30 percent by weight of cellulose diacetate.
4. An electrophotographic photosensitive plate as claimed in claim 1, wherein the protective polymer coating layer is composed of 72 to percent by weight of polvinyl butyral and 20 to 28 percent by weight of cellulose triacetate.
5. An electrophotographic photosensitive plate which comprises, on a support of an inorganic material selected from the group consisting of aluminum, zinc, brass, copper, and electroconductive glass, :1 photoconductive layer made of a substance selected from the group consisting of selenium, selenium-tellurium, zinc oxide, lead oxide and cadmium sulfide and a protective polymer coating layer coated on the opposite surface of said photoconductive layer, said protective coating having a thickness not greater than one micron and comprising a polyvinyl butyral having a butyralation degree of 57 to 65 mole percent and a cellulose derivative compatible with said polyvinyl butyral, said polyvinyl butyral being present in said coating in an amount varying from 50 to percent, by weight, and said cellulose derivative being present in said coating in an amount ranging from l0 to 50 percent, by weight, said protective'polymer coating layer having a volume resistivity no greater than 10 ohm cm.
6. An electrophtograp'hic photosensitive plate, as claimed in claiml wherein said protective polymer coating layer also contains 3 to 8 percent of ethyl cellulose.

Claims (6)

1. An electrophotographic photosensitive plate, comprising an electroconductive layer, a photoconductive layer thereon, and a protective polymer coating layer on the opposite surface of said photoconductive layer, said protective coating having a thickness not greater than one micron and comprising polyvinyl butyral having a butyralation degree of 57 to 65 mole percent and a cellulose derivative selected from the group consisting of cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose acetobutyrate, and cellulose nitrate, said polyvinyl butyral being present in said coating in an amount varying from 50 to 90 percent by weight, and said cellulose derivative being present in said coating in an amount ranging from 10 to 50 percent, by weight, said protective polymer coating layer having a volume resistivity no greater than 1015 ohm-cm.
2. An electrophotographic photosensitive plate as claimed in claim 1, wherein the protective polymer coating layer is composed of 50 to 80 percent by weight of polyvinyl butyral and 20 to 50 percent by weight of cellulose nitrate.
3. An electrophotographic photosensitive plate as claimed in claim 1, wherein the protective polymer coating layer is composed of 70 to 90 percent by weight of polyvinyl butyral and 10 to 30 percent by weight of cellulose diacetate.
4. An electrophotographic photosensitive plate as claimed in claim 1, wherein the protective polymer coating layer is composed of 72 to 80 percent by weight of polvinyl butyral and 20 to 28 percent by weight of cellulose triacetate.
5. AN ELECTROPHOTOGRAPHIC PHOTOSENSITIVE PLATE WHICH COMPRISES, ON A SUPPORT OF AN INORGANIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF ALUMINUM, ZINC, BRASS, COPPER, AND ELECTROCONDUCTIVE GLASS, A PHOTOCONDUCTIVE, LAYER MADE OF A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SELENIUM, SELENIUM-TELLURIUM, ZINC OXIDE, LEAD OXIDE AND CADMIUM SULFIDE AND A PROTECTIVE POLYMER COATING LAYER COATED ON THE OPPOSITE SURFACE OF SAID PHOTOCONDUCTIVE LAYER, SAID PROTECTIVE COATING HAVING A THICKNESS NOT GREATER THAN ONE MICRON AND COMPRISING A POLYVINYL BUTYRAL HAVING A BUTYRALATION DEGREE OF 57 TO 65 MOLE PERCENT AND A CELLULOSE DERIVATIVE COMPBATIBLE WITH SAID POLYVINYL BUTRYAL, SAID POLYVINYL BUTYRAL BEING PRESENT IN SAID COATING IN AN AMOUNT VARYING FROM 50 TO 90 PERCENT, BY WEIGHT, AND SAID CELLULOSE DERIVATIVE BEING PRESENT IN SAID COATING IN AN AMOUNT RANGING FROM 10 TO 50 PERCENT, BY WEIGHT, SAID PROTECTIVE POLYMER COATING LAYER HAVING A VOLUME RESISTIVITY NO GREATER THAN 10**15 OHM - CM.
6. An electrophtographic photosensitive plate, as claimed in claim 1 wherein said protective polymer coating layer also contains 3 to 8 percent of ethyl cellulose.
US00275212A 1971-07-26 1972-07-26 Electrophotographic photosensitive plate Expired - Lifetime US3850632A (en)

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US (1) US3850632A (en)
JP (1) JPS5115748B1 (en)
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3966471A (en) * 1973-12-25 1976-06-29 Ricoh Co., Ltd. Electro photosensitive materials with a protective layer
WO1990007146A1 (en) * 1988-12-14 1990-06-28 Tazenkov Boris A Electrophotographic image carrier

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2803542A (en) * 1955-07-26 1957-08-20 Haloid Co Xerographic plate
US2860048A (en) * 1955-06-13 1958-11-11 Haloid Xerox Inc Xerographic plate
US2901348A (en) * 1953-03-17 1959-08-25 Haloid Xerox Inc Radiation sensitive photoconductive member
US3127331A (en) * 1959-06-15 1964-03-31 Reverse current electrolytic process
US3140174A (en) * 1955-01-19 1964-07-07 Xerox Corp Process for overcoating a xerographic plate
US3170790A (en) * 1959-01-08 1965-02-23 Xerox Corp Red sensitive xerographic plate and process therefor
US3355289A (en) * 1962-05-02 1967-11-28 Xerox Corp Cyclical xerographic process utilizing a selenium-tellurium xerographic plate
US3434832A (en) * 1964-10-30 1969-03-25 Xerox Corp Xerographic plate comprising a protective coating of a resin mixed with a metallic stearate
US3652268A (en) * 1970-03-16 1972-03-28 Dick Co Ab Barrier coated electrophotographic sheet suitable for liquid development
US3761259A (en) * 1968-06-14 1973-09-25 Ricoh Kk Electrophotographic element containing an intermediate layer

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2901348A (en) * 1953-03-17 1959-08-25 Haloid Xerox Inc Radiation sensitive photoconductive member
US3140174A (en) * 1955-01-19 1964-07-07 Xerox Corp Process for overcoating a xerographic plate
US2860048A (en) * 1955-06-13 1958-11-11 Haloid Xerox Inc Xerographic plate
US2803542A (en) * 1955-07-26 1957-08-20 Haloid Co Xerographic plate
US3170790A (en) * 1959-01-08 1965-02-23 Xerox Corp Red sensitive xerographic plate and process therefor
US3127331A (en) * 1959-06-15 1964-03-31 Reverse current electrolytic process
US3355289A (en) * 1962-05-02 1967-11-28 Xerox Corp Cyclical xerographic process utilizing a selenium-tellurium xerographic plate
US3434832A (en) * 1964-10-30 1969-03-25 Xerox Corp Xerographic plate comprising a protective coating of a resin mixed with a metallic stearate
US3761259A (en) * 1968-06-14 1973-09-25 Ricoh Kk Electrophotographic element containing an intermediate layer
US3652268A (en) * 1970-03-16 1972-03-28 Dick Co Ab Barrier coated electrophotographic sheet suitable for liquid development

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3966471A (en) * 1973-12-25 1976-06-29 Ricoh Co., Ltd. Electro photosensitive materials with a protective layer
WO1990007146A1 (en) * 1988-12-14 1990-06-28 Tazenkov Boris A Electrophotographic image carrier

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GB1334997A (en) 1973-10-24
JPS5115748B1 (en) 1976-05-19

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Owner name: KONICA CORPORATION, JAPAN

Free format text: RELEASED BY SECURED PARTY;ASSIGNOR:KONISAIROKU PHOTO INDUSTRY CO., LTD.;REEL/FRAME:005159/0302

Effective date: 19871021