US2990279A - Electrostatic printing - Google Patents

Electrostatic printing Download PDF

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Publication number
US2990279A
US2990279A US611833A US61183356A US2990279A US 2990279 A US2990279 A US 2990279A US 611833 A US611833 A US 611833A US 61183356 A US61183356 A US 61183356A US 2990279 A US2990279 A US 2990279A
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United States
Prior art keywords
coating
weight
vehicle
photoconducting
electrostatic
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Expired - Lifetime
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US611833A
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English (en)
Inventor
Julius A Crumley
Raymond W James
Shulman Joseph
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RCA Corp
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RCA Corp
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Filing date
Publication date
Priority to NL221062D priority Critical patent/NL221062A/xx
Priority to NL107387D priority patent/NL107387C/xx
Priority to BE561070D priority patent/BE561070A/xx
Priority to DENDAT1065723D priority patent/DE1065723B/de
Priority to US611833A priority patent/US2990279A/en
Application filed by RCA Corp filed Critical RCA Corp
Priority to GB28058/57A priority patent/GB865072A/en
Priority to FR1182029D priority patent/FR1182029A/fr
Priority to SE866857A priority patent/SE208845C1/xx
Priority to CH5093557A priority patent/CH364985A/de
Application granted granted Critical
Publication of US2990279A publication Critical patent/US2990279A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/05—Organic bonding materials; Methods for coating a substrate with a photoconductive layer; Inert supplements for use in photoconductive layers
    • G03G5/0528—Macromolecular bonding materials
    • G03G5/0532—Macromolecular bonding materials obtained by reactions only involving carbon-to-carbon unsatured bonds
    • G03G5/0535—Polyolefins; Polystyrenes; Waxes
    • 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
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
    • G03G5/07—Polymeric photoconductive materials
    • G03G5/071—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • 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
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/05—Organic bonding materials; Methods for coating a substrate with a photoconductive layer; Inert supplements for use in photoconductive layers
    • G03G5/0528—Macromolecular bonding materials
    • G03G5/0532—Macromolecular bonding materials obtained by reactions only involving carbon-to-carbon unsatured bonds
    • G03G5/0553—Polymers derived from conjugated double bonds containing monomers, e.g. polybutadiene; Rubbers
    • 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
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/08—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being inorganic

Definitions

  • An electrostatic printing process is that type of process for producing a visible record, reproduction, or copy which includes, as an intermediate step, converting a light image or electric signal into an electrostatic charge pattern on an electrically-insulating base. The process includes the conversion of the electrostatic charge pattern into a visible image by the application thereto of electrostatically-attractable particles.
  • An electrostatic printing process using a photoconducting insulating stratum to convert a light image into an electrostatic charge pattern is described by C. J. Young and H. G. Greig in Electrofax Direct Electrophotographic Printing on Paper, RCA Review, volume XV, No. 4, pages 469 to 484 (December 1954), hereinafter referred to as the Young and Greig publication.
  • a typical electrostatic printing process utilizing a photoconducting insulating stratum includes first producing a blanket electrostatic charge on the surface of the photoconducting stratum.
  • the electrostatic charge may be stored on the surface for a time in the dark.
  • the rate at which this stored electric charge is dissipated when the stratum is maintained in darkness is hereinafter referred to as the dark decay of the stratum.
  • a light image is focused on the charged surface, discharging the portions of the surface irradiated with light, leaving the remainder of the surface in a charged condition, and thereby forming an electrostatic image thereon
  • the electrostatic image is rendered visible by applying to the electrostatic image a developer substance, such as a pigmented thermoplastic resin powder, which is held ole..- trostatically to the charged areas of the surface.
  • the visible image thus formed may be fixed directly to the surface, for example, by fusing the image thereto.
  • One type of recording element usable in the foregoing electrostatic printing process comprises a cellulosic sheet coated with a particulate photoconductor dispersed in an electrically-insulating, film-forming vehicle, for example, ordinary paper coated with particulate photoconducting white zinc oxide suspended in a silicone resin.
  • Such recording elements are relatively cheap, flexible, and are prepared in standard web coating machines from solvent coating mixtures which are air dried.
  • Silicone resins as well as many other resins taught in the prior art, are thermosetting. As previously prepared for use in electrostatic printing, the silicone resin is not set or is uncured and, as a result, retains its flow and adhesive properties. One difliculty of such coated paper is that it blocks when wound tightly in rolls. Blocking is the adherence of adjacent layers of paper due to the adhesive properties of the coatings.
  • An object of this invention is to provide improved photosensitive compositions and improved recording elements for electrostatic printing.
  • Another object is to provide improved recording elements for electrostatic printing which are non-blocking, cheap, flexible, and easily prepared in a standard web coating machine.
  • a further object is to provide improved recording elements particularly adapted for use in high speed electrostatic printing machines.
  • the improved compositions for electrostatic printing comprise, generally, a particulate photoconductor suspended in an electrically-insul'ating, film-forming vehicle, wherein said vehicle includes at least two compatible, hydrophobic, solvent-soluble resins in proportions to provide the desired non-blocking and non-adhesive characteristics to said composition, one of said resins being nonadhesive at the temperature at which the recording element is used and the other of said resins having a low electrical conductivity.
  • a combination of resins as the vehicle, it is possible to adjust the physical and electrical properties of the material over a wide range, and particularly to provide a non-blocking material while retaining other desirable physical and electrical properties as well as low cost and ease of manufacture.
  • An example of a recording element of the invention comprises a stratum comprising a major proportion of a particulate photoconductor, such as photoconducting zinc oxide, suspended in an electrically-insulating, film-forming vehicle, wherein said vehicle is a mixture of a high styrene-butadiene rubber resin, such as Pliolite, and a hard hydrocarbon resin such as Piccopale.
  • the invention includes recording elements comprising the foregoing stratum which may be self-supporting or a stratum which is supported upon a backing, such as paper.
  • FIGURE 1 is a sectional, elevational view recording element according to the inventio FIGURE 2 is a partially-schematic, sectional view of an apparatus for producing a blanket electrostatic charge upon a recording element produced by the method of the invention
  • FIGURE 3 is a partiallysectional, elevational view-of an apparatus for projecting a light to forma contact image upon the charged recording element of FIGURE 2, and
  • FIGURE 4 is a sectional view of an apparatus for developing an electrostatic image upon the recording element produced in FIGURE 3.
  • a recording element comprising a backing Z1 and a photoconducting coating 23 thereon according to the invention is prepared as follows.
  • a coating mixture is prepared of the followingformulation inparts by weight:
  • Rubber Co., Akron, Ohio 9 F21 Plasticizer marketed by the National Lead 00.
  • Toluene 100 The mixture is ball-milled to a smooth uniform consistency and is coated on the surface of a paper backing 21, such as Gleamcoat CIS-40 marketed by Crocker, Burbank Papers, Inc., Fitchburg, Massachusetts to a thickness to provide a final dry coating of about 0.001 inch.
  • a paper backing 21 such as Gleamcoat CIS-40 marketed by Crocker, Burbank Papers, Inc., Fitchburg, Massachusetts
  • Any conventional coating process may be used.
  • One convenient coating process is by flow-coating.
  • Other coating processes may be by spraying, dip-coating or spin-coating.
  • the coating 23 is air dried. Heat may be used to accelerate the drying step. Upon drying, the recording element is ready for use in electrostatic printing.
  • the recording element described is non-blocking, cheap, flexible and easily prepared in standard web coating machines. It is particularly adapted for use in high speed machines by providing a fast response in the electrostatic printing process. In addition the recording element is white in color and does not contain any toxic ingredients.
  • the recording elements of the invention may be used for electrostatic printing by any of the methods described in the Young and Greig publication op. cit.
  • the recording element of Example 1 may be utilized in an electrostatic printing process according to the following steps.
  • the recording element is placed with the backing 21 upon a grounded metal plate 25 and in darkness, an electrostatic charging device 61 passed over the photoconducting coating 23 to provide an electrostatic charge thereon.
  • the charging device 51 may comprise an array of fine wires 53 mounted near the grounded metal plate 25.
  • a source of DC. voltage is connected between the wires 53 and the grounded plate 25 to provide a negative charge on the wires with respect to grounded plate 25.
  • the voltage should be sufliciently high to cause a corona discharge adjacent the wires.
  • the apparatus and process may produce a blanket positive charge if the polarity of the wires 53 is positive with respect to the grounded plate 25.
  • the next step in the process is to discharge selected areas of the charged surface of the recording element in order to produce an electrostatic image thereon.
  • this may be accomplished by placing a photographic transparency 61 upon the charged surface of the coating 23 and exposing to light derived, for example, from a lamp S9 in the manner of conventional contact printing. An exposure of about 1 second from a 100 watt tungsten lamp about 24 inches from the recording element for a normal density photographic transparency has been found to be adequate.
  • the light image may be produced by any of the ordinary photographic processes as by projection, contact, or reflex. Any type of electromagnetic radiation may be used provided a portion thereof falls within the spectral sensitivity of the photoconducting coating 23. In the example, visible blue and ultraviolet light may be used.
  • visible light For other photoconducting strata, visible light, infra-red, ultraviolet or X-rays may be used. Wherever the light strikes the surface of the photoconducting coating 23, the electrostatic charge thereon is reduced or removed. This leaves an electrostatic image or pattern of charges corresponding to the non-illuminated areas of the light image.
  • the electrostatic image may be stored for a time if desired. Ordinarily the next step is to develop the electrostatic image with a finely-divided developer substance such as a finely-divided powder or an ink mist.
  • development of the electrostatic image is preferably accomplished by maintaining the recording element in darkness and passing a developer brush 55 containing a developer powder across the surface of photoconducting coating powder 23 bearing the electrostatic image. Areas 27 of developer powder are deposited on those areas of the surface retaining an electrostatic charge.
  • the developer brush comprises a mixture of magnetic carrier particles, for example powdered iron, and the developer powder. The mixture is secured in a magnetic field by a magnet 57 to form a developer brush.
  • a preferred carrier material for the developer mix consists of alcoholized iron, that is, iron particles free from grease and other alcohol-soluble impurities. These iron particles are preferably relatively small in size, being in their largest dimension about .002 to .008". Satisfactory results are also obtained using a carrier consisting of iron particles of a somewhat wider range of sizes from about .001" to .020".
  • a preferred developer powder may be prepared as follows: A mixture comprising 200 grams of 200 mesh Piccolastic resin 4358 (an elastic thermoplastic resin composed of polymers of styrene, substituted styrene and its homologs) marketed by the Pennsylvania Industrial Company, Clairton, Pa., 12 grams of Carbon Black G, marketed by the Eimer and Amend C0,, New York, N.Y., 12 grams of spirit Nigrosine S.S.B. marketed by the Allied Chemical and Dye (30., New York, N.Y., and 8 grams of Iosol Black, marketed by the Allied Chemical and Dye Co., New York, N.Y. are thoroughly mixed in a stainless steel beaker at about 200 C.
  • Piccolastic resin 4358 an elastic thermoplastic resin composed of polymers of styrene, substituted styrene and its homologs
  • the mixing and heating should be done in as short a time as possible.
  • the melt is poured into a brass tray and allowed to cool and harden.
  • the hardened mix is then broken up and ball-milled for about 20 hours.
  • the powder is screened through a 200 mesh screen and is then ready for use as a developer powder.
  • This powder takes on a positive electrostatic charge when mixed with glass beads or iron powder. It therefore develops an electrostatic image composed of negative charges.
  • Two to four grams of the developer powder and grams of the magnetic carrier material are blended together giving the preferred developer mix. Other ratios may be used.
  • the developer powder may be chosen from a large class of materials.
  • the developer powder is preferably electrically-charged to aid in the development of the electrostatic latent image.
  • the powder may be electricallycharged because the powder (1) is electroscopic, or (2) has interacted with other particles with which it is triboelectrically active or (3) has been charged from an electric source such as a corona discharge.
  • suitable developer powders are powdered zinc, powdered copper, carbon, sulfur, natural and synthetic resins or mixtures thereof.
  • the developer powder may be applied to the electrostatic image in other ways, for example, it may be dusted on to the image, or it may be mixed with glass beads, magnetite, or other suitable carrier particles, and the mixture then brought into contact with the surface of the photoconducting stratum.
  • the beads serve merely as a temporary carrier, releasing the powder particles upon contact with the charged surface.
  • the type of developer powder described is a positivelycharged powder and will adhere readily to negativelycharged areas of the electrostatic image.
  • the developed image described the developed areas of the image correspond to the non-illuminated portions of the light image. If the photoconducting stratum is charged positively, and the same steps are carried through as above-described, a reverse image is obtained. If a negatively-charged powder is used in place of the positively-charged powder,
  • the developed image 27 is now fixed to the photoconducting coating 23. If the developer powder or the vehicle in the photoconducting coating 23 has a relatively low melting point, the developed image may be fixed by heating, for example with an infra red lamp, to fuse the powder to the surface. Sulfur or synthetic thermoplastic resin powders may be fixed in this way. Alternatively, the developed image 27 may be pressed into the coating 23. Another method of fixing the developed image 27 is to apply a thin coating of a solvent for the material of the developed image 31. The solvent softens the developer powder particles and causes them to adhere to one another and to the photoconducting coating 23. Alternatively, a solvent may be used to soften the photoconducting stratum 23 and cause the developed image to adhere thereto. Upon standing, and preferably with the application of a slight amount of heat, the solvent is evaporated from therecording element.
  • Example 1 While the backing 21 of Example 1 is a particular brand of paper, any substrate may be used. Thus, one may use any cellulosic material such as paper, cellophane, cellulose acetate or mylar metallic material such as copper, aluminum or brass, or mineral material such as glass or mica.
  • the substrate or backing 21, may be in any desired shape or configuration. It is preferred, although not necessary, that the substrate have a higher electrical conductivity than the final photoconducting coating 23.
  • the photoconducting coating 23 must be a material which exhibits a substantial change in electrical conductivity upon exposure to light, such that an electrostatic charge stored on the surface thereof may be discharged thereby.
  • the photoconducting coating 23 determines the spectral response, the speed of response and the contrast characteristic of the recording element. By a proper choice of materials for the photoconducting coating 23, any spectral response, speed of response or contrast characteristic over a wide range may be obtained. Many different powdered photoconductors may be used in the photoconducting stratum in place of the white photoconducting zinc oxide.
  • the photoconducting stratum may be any of the photoconducting coatings described in the Young and Greig publication, ibid.
  • Test 1 A mixture was prepared comprising about milligrams of dry zinc oxide powder and a few drops of an 80% solution of silicone resin in xylene (G.E. SR-82, marketed by the General Electric Company, Silicone Products Division, Waterford, N.Y.), diluted with toluene in the ratio 60 grams solution to 105 grams toluene.
  • the mixture was coated on filter paper and dried to produce a dry coating over an area about 0.25 inch in diameter.
  • the dry coating was cooled to about l90 C. and examined in light from a mercury vapor lamp having a maximum output at about 3650 A.
  • the zinc oxides which produce printable coatings produce a lavender or orange luminescence by this test. Other zinc oxides exhibit a green or yellow luminescence.
  • Test 2 About 0.25 gram of dry zinc oxide powder was placed in a silica boat. The boat was inserted into a silica tube and the system flushed with hydrogen gas. The tube and boat were fired for about 5 minutes at about 1000 C. in a stagnant hydrogen atmosphere. The boat was cooled in hydrogen to room temperature. The fired zinc oxide was examined in light from a mercury vapor lamp having a maximum output at about 3650 A. The zinc oxides which produce printable coatings luminesce brightly. Other zinc oxides luminesce weakly or not at all.
  • the table compiles the results of the two tests on typical commercially-available zinc oxides and indicates the correlation between these tests and the printability of the zinc oxides used in the coatings of the invention.
  • the zinc oxides marked G in column 3 print well and are preferred in the photoconducting coatings 23.
  • Example 1 is representative of the system of mixtures of a rubber resin (Pliolite) and a hard hydrocarbon resin (P'iccopale). Both of these classes of resins are well known to persons skilled in the art of chemistry.
  • Pliolite SSD is a styrene-butadiene copolymer rubber resin. Increasing the proportion of Pliolite in the coating, increases the flexibility and toughness and reduces tackiness of the coating.
  • Piccopale 100 is a hard hydrocarbon produced by the polymerization of unsaturates derived from the deep cracking of petroleum. Increasing the proportion of Piccopale in the coating, increases ease of dispersion of zinc oxide, reduces the tendency to form orange peel texture, and improves the drying characteristics of the coating.
  • Piccopale refers to the polymerization product obtained by catalytic cracking under carefully controlled conditions, a mixture of monomers having an average molecular weight of approximately 90, and composed essentially of dienes and reactive olefines to produce a hard solid resin with a resulting average molecular weight approximately 1100 and generally approximating 100 C. ball and ring softening point.
  • Piccopale appears to be methylated paraffin chains containing only a limited amount of unsaturation either of trans type II or terminal double bonds. The large number of tertiary hydrogens produce misleading results when the material is analyzed for unsaturation by the Wijs iodine method unless a correction is made for substitution.
  • the combination of a rubber resin and a hard hydrocarbon resin, and particularly Pliolite and Piccopale, may be used in any proportion with respect to one another to impart more or less of the desired characteristics. All of the mixtures with Pliolite and Piccopale are operative in the above-described electrostatic printing process.
  • a plasticizer may be used in conjunction with the vehicle to enhance foldability, flexibility and pliability to the final coating.
  • the choice of the plasticizer is determined by the vehicle used.
  • Some of the common types of plasticizers that may be used include phosphates, such as tricresyl phosphate and triphenyl phosphate; phthalates, such as di-Z-ethylhexyl phthalate; and petroleum derivatives such as Sovaloid C manufactured by Socony- Vacuum Oil Company, New York, N.Y.
  • the quantity of plasticizer used is determined by the degree of flexibility required in the coating and by the particular vehicle used.
  • the quantity of plasticizer may be present in an amount between zero and eightly percent by weight of 8 the vehicle. However, a quantity of plasticizer is preferred.
  • the proportion of powdered photoconductor to vehido in the final coating may vary over a very wide range.
  • the preferred ranges are to 900 parts by weight of photoconductor to 100 parts by weight of vehicle.
  • the optimum proportion will depend upon the nature of the photoconductor, the nature of the vehicle and the results desired.
  • the speed of response of the recording element de pends upon the nature of the photoconducting material, the nature of the vehicle, and the ratio by weight of photoconductor to vehicle. Since the speed of response depends upon a number of characteristics, almost any desired response may be obtained by the proper selection of materials and composition. A proper selection of materials and compositions will also determine how long an electrostatic image may be stored on the surface of the photoconductive coating since storage of the electrostatic image depends upon the electrical resistivity of the material. Generally, the higher the resistivity of the coating the longer the storage time for the material.
  • a dye for sensitizing the photoconductin-g coating may be incorporated into the coating when the dispersions are prepared or after the coatings have dried.
  • Dyes such as Rose Bengal, Eosin Y, Erythrosin and Fluoresceing are convenient for sensitizing coatings such as the coating of Example 1.
  • the coating of the final product may be any thickness. However, it is preferred that the coating thickness be about 0.0003 to about 0.002 inch thick. For the coating of Example 1, a coating 0.001 inch thick is preferred.
  • the photoconductor may be suspended in the vehicle in any one of several ways.
  • the simplest way is to dissolve the vehicle in an organic solvent capable of effecting solution and then mixing in the powdered photoconductor.
  • the photoconductor may be dry blended, as by kneading with the vehicle heated to a sufficiently high temperature to render it plastic.
  • EXAMPLE 8 Florence Green Seal-8 zinc oxide 13$ Acryloid B-82 resin marketed by Resinous Products Division, Rohm and Haas Company, 222 W. Washington Square, Philadelphia 5, Pennsylvania 35 Ester Gum 8L resin marketed by Hercules Powder Company, Synthetics Dept., Wilmington 99, Delaware 10 Tricresyl phosphate plasticizer 5 Toluene 150
  • EXAMPLE 9 Florence Green Seal-8 zinc oxide 150 Pliolite S-5 resin Cumar T-3 resin marketed by Barrett Division, Allied Chemical and Dye Corporation, 40 Rector Street, New York 6, NY.
  • compositions for coating a substrate to provide thereon a photoconductiveinsulating surface comprising about 100 to 900 parts by weight of a particulate zinc oxide photoconductor and about 100 parts by weight of an electrically-insulating film-forming vehicle, said vehicle comprising a mixture of about to 62% by weight of a resinous copolymer of styrene with butadiene, said copolymer including at least 80% by weight of said styrene and about 70% to 38% by weight of a hard hydrocarbon produced by the polymerization of unsaturates derived from the deep cracking of petroleum having an average molecular weight of about 1100 and a ball and ring softening point of about 100 C.
  • said paraffin resin comprising a polymerization product obtained by catalytic reacting a mixture of monomers having an average molecular weight of about 90 and consisting essentially of dienes and reactive olefins.
  • a recording element comprising a substrate having thereon a photoconductive insulating coating comprising about 100 to 900 parts by weight of a particulate zinc oxide photoconductor suspended in about 100 parts by weight of an electrically-insulating film-forming vehicle comprising a mixture of about 30% to 62% by weight of a resinous copolymer of styrene with butadiene, said copolymer including at least by weight of said styrene and about 70% to 38% by weight of a hard hydrocarbon produced by the polymerization of unsaturates derived from the deep cracking of petroleum having an average molecular weight of about 1100 and a ball and ring softening point of about 100 C., said parafiin resin comprising a polymerization product obtained by catalytic reacting a mixture of monomers having an average molecular weight of about and consisting essiting essentially of dienes and reactive olefins.
  • a recording element comprising a paper backing having a photoconductive insulating coating thereon comprising about 125 parts by weight of a photoconductive zinc oxide dispersed in an electrically-insulating filmforming vehicle, said vehicle comprising a mixture of about 25 parts by weight of a resinous copolymer of styrene with butadiene, said copolymer including at least 80% by weight of said styrene, 10 parts by weight of a hard hydrocarbon produced by the polymerization of unsaturates derived from the deep cracking of petroleum having an average molecular weight of about 1100 and a ball and ring sofitening point of about C., said paraflin resin comprising a polymerization product obtained by catalytic reacting a mixture of monomers having an average molecular weight of about 90 and consisting essentially of dienes and reactive olefins, and 10 parts by weight of plasticizer.
  • a recording element comprising a paper backing having a photoconductive insulating coating thereon comprising about 45 parts by weight of photoconductive zinc oxide dispersed in an electrically-insulating filmforming vehicle, said vehicle comprising about 9 parts by weight of a resinous copolymer of styrene with butadiene, said copolymer including at least 80% by weight of said styrene, 6 parts by weight of a hard hydrocarbon produced by the polymerization of unsaturates derived from the deep cracking of petroleum and 1.5 parts by weight of a plasticizer.

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  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Inorganic Chemistry (AREA)
  • Photoreceptors In Electrophotography (AREA)
US611833A 1956-09-25 1956-09-25 Electrostatic printing Expired - Lifetime US2990279A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
BE561070D BE561070A (de) 1956-09-25
DENDAT1065723D DE1065723B (de) 1956-09-25
NL221062D NL221062A (de) 1956-09-25
NL107387D NL107387C (de) 1956-09-25
US611833A US2990279A (en) 1956-09-25 1956-09-25 Electrostatic printing
GB28058/57A GB865072A (en) 1956-09-25 1957-09-05 Electrostatic printing
FR1182029D FR1182029A (fr) 1956-09-25 1957-09-05 Dispositif d'impression électrostatique
SE866857A SE208845C1 (de) 1956-09-25 1957-09-24
CH5093557A CH364985A (de) 1956-09-25 1957-09-25 Flächenförmiges Material für elektrostatisches Drucken

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US611833A US2990279A (en) 1956-09-25 1956-09-25 Electrostatic printing

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US2990279A true US2990279A (en) 1961-06-27

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US611833A Expired - Lifetime US2990279A (en) 1956-09-25 1956-09-25 Electrostatic printing

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US (1) US2990279A (de)
BE (1) BE561070A (de)
CH (1) CH364985A (de)
DE (1) DE1065723B (de)
FR (1) FR1182029A (de)
GB (1) GB865072A (de)
NL (2) NL107387C (de)
SE (1) SE208845C1 (de)

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3102026A (en) * 1957-12-24 1963-08-27 Metcalfe Kenneth Archibald Electrophotographic reflex and contact printing
US3128204A (en) * 1956-11-14 1964-04-07 Agfa Ag Process of preparing photoconductive layers for electrophotography
US3132941A (en) * 1960-12-02 1964-05-12 Eastman Kodak Co Superior binders for photoconductive layers containing zinc oxide
US3174856A (en) * 1961-06-09 1965-03-23 Minnesota Mining & Mfg Electrolytic recording sheets
US3226227A (en) * 1960-09-02 1965-12-28 Rca Corp Method of producing a solvent-resistant pattern using developed electrostatic image formation techniques
US3250613A (en) * 1961-05-01 1966-05-10 Eastman Kodak Co Use of amines in photoconductographic coatings
US3251686A (en) * 1960-07-01 1966-05-17 Xerox Corp Xerographic process
US3378370A (en) * 1964-02-06 1968-04-16 Interchem Corp Recording elements for electrostatic printing
US3378371A (en) * 1965-04-08 1968-04-16 Eastman Kodak Co Photoconductive material for electrophotography
US3471625A (en) * 1957-02-15 1969-10-07 Harris Intertype Corp Electrophotographic coating containing finely divided photoconductor in a synthetic polymer having ionizable functional groups
US3486922A (en) * 1967-05-29 1969-12-30 Agfa Gevaert Nv Development of electrostatic patterns with aqueous conductive developing liquid
US3522041A (en) * 1967-01-19 1970-07-28 Addressograph Multigraph Photoelectrostatic recording member
US3581661A (en) * 1968-04-03 1971-06-01 Sperry Rand Corp Electrostatically imaged lithographic plate
US3918969A (en) * 1968-01-02 1975-11-11 Xerox Corp Migration imaging method employing a uniform exposure step
US3960555A (en) * 1964-10-12 1976-06-01 Xerox Corporation Photographic charging and imaging process
FR2305759A1 (fr) * 1975-03-26 1976-10-22 Xerox Corp Procede de fabrication de couches photoconductrices a copolymere heterogene et nouveaux produits ainsi obtenus
US4134762A (en) * 1976-07-02 1979-01-16 The Commonwealth Of Australia Selective photoconductor-binder coating of absorbent surfaces
US20110168924A1 (en) * 2007-12-21 2011-07-14 Jendrejack Richard M Charge alteration using ultraviolet radiation

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JPS6022349B2 (ja) * 1977-10-15 1985-06-01 キヤノン株式会社 電子写真感光体

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US2169840A (en) * 1936-11-28 1939-08-15 Hazeltine Corp Cathode-ray signal-generating tube
US2331444A (en) * 1941-09-16 1943-10-12 Titanium Alloy Mfg Co Photoconductive material and method
US2611719A (en) * 1946-09-21 1952-09-23 Wingfoot Corp Base coated with a high styrenebutadiene copolymer
US2554017A (en) * 1946-11-14 1951-05-22 Timefax Corp Electroresponsive recording blank
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US3128204A (en) * 1956-11-14 1964-04-07 Agfa Ag Process of preparing photoconductive layers for electrophotography
US3471625A (en) * 1957-02-15 1969-10-07 Harris Intertype Corp Electrophotographic coating containing finely divided photoconductor in a synthetic polymer having ionizable functional groups
US3102026A (en) * 1957-12-24 1963-08-27 Metcalfe Kenneth Archibald Electrophotographic reflex and contact printing
US3251686A (en) * 1960-07-01 1966-05-17 Xerox Corp Xerographic process
US3226227A (en) * 1960-09-02 1965-12-28 Rca Corp Method of producing a solvent-resistant pattern using developed electrostatic image formation techniques
US3132941A (en) * 1960-12-02 1964-05-12 Eastman Kodak Co Superior binders for photoconductive layers containing zinc oxide
US3250613A (en) * 1961-05-01 1966-05-10 Eastman Kodak Co Use of amines in photoconductographic coatings
US3174856A (en) * 1961-06-09 1965-03-23 Minnesota Mining & Mfg Electrolytic recording sheets
US3378370A (en) * 1964-02-06 1968-04-16 Interchem Corp Recording elements for electrostatic printing
US3960555A (en) * 1964-10-12 1976-06-01 Xerox Corporation Photographic charging and imaging process
US3378371A (en) * 1965-04-08 1968-04-16 Eastman Kodak Co Photoconductive material for electrophotography
US3522041A (en) * 1967-01-19 1970-07-28 Addressograph Multigraph Photoelectrostatic recording member
US3486922A (en) * 1967-05-29 1969-12-30 Agfa Gevaert Nv Development of electrostatic patterns with aqueous conductive developing liquid
US3918969A (en) * 1968-01-02 1975-11-11 Xerox Corp Migration imaging method employing a uniform exposure step
US3581661A (en) * 1968-04-03 1971-06-01 Sperry Rand Corp Electrostatically imaged lithographic plate
FR2305759A1 (fr) * 1975-03-26 1976-10-22 Xerox Corp Procede de fabrication de couches photoconductrices a copolymere heterogene et nouveaux produits ainsi obtenus
US4134762A (en) * 1976-07-02 1979-01-16 The Commonwealth Of Australia Selective photoconductor-binder coating of absorbent surfaces
US20110168924A1 (en) * 2007-12-21 2011-07-14 Jendrejack Richard M Charge alteration using ultraviolet radiation

Also Published As

Publication number Publication date
NL221062A (de)
NL107387C (de)
GB865072A (en) 1961-04-12
BE561070A (de)
DE1065723B (de)
FR1182029A (fr) 1959-06-22
CH364985A (de) 1962-10-15
SE208845C1 (de) 1966-11-08

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