US3378370A - Recording elements for electrostatic printing - Google Patents

Recording elements for electrostatic printing Download PDF

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Publication number
US3378370A
US3378370A US343152A US34315264A US3378370A US 3378370 A US3378370 A US 3378370A US 343152 A US343152 A US 343152A US 34315264 A US34315264 A US 34315264A US 3378370 A US3378370 A US 3378370A
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US
United States
Prior art keywords
resins
blend
ethylene
haze
film
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US343152A
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English (en)
Inventor
Sebastian T Brancato
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Interchemical Corp
Original Assignee
Interchemical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Interchemical Corp filed Critical Interchemical Corp
Priority to US343152A priority Critical patent/US3378370A/en
Priority to GB3327/65A priority patent/GB1077053A/en
Priority to FR3420A priority patent/FR1424079A/fr
Priority to BE659027D priority patent/BE659027A/xx
Priority to ES0309018A priority patent/ES309018A1/es
Priority to DE19651497157 priority patent/DE1497157A1/de
Priority to CH157965A priority patent/CH438946A/fr
Priority to NL6501531A priority patent/NL6501531A/xx
Application granted granted Critical
Publication of US3378370A publication Critical patent/US3378370A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02Charge-receiving layers
    • G03G5/04Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/05Organic bonding materials; Methods for coating a substrate with a photoconductive layer; Inert supplements for use in photoconductive layers
    • G03G5/0528Macromolecular bonding materials
    • G03G5/0557Macromolecular bonding materials obtained otherwise than by reactions only involving carbon-to-carbon unsatured bonds
    • G03G5/056Polyesters
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L67/00Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
    • C08L67/02Polyesters derived from dicarboxylic acids and dihydroxy compounds
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D167/00Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Coating compositions based on derivatives of such polymers
    • C09D167/02Polyesters derived from dicarboxylic acids and dihydroxy compounds
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S525/00Synthetic resins or natural rubbers -- part of the class 520 series
    • Y10S525/931Blend of stated incompatibility

Definitions

  • ABSTRACT OF THE DISCLOSURE A recording element for electrostatic-printing wherein the photoconductive coating contains zinc oxide dispersed in a film of two partially incompatible resins.
  • This invention relates to electrostatic printing and particularly to improved recording elements for electrostatic printing and methods of producing these recording elements.
  • An electrostatic printing process is a process for producing a visible image or copy by converting a light image or signal into an electrostatic charge pattern on an electrically insulating base. The charge pattern is then converted or developed into a visible image by the application thereto of electrically-attractable particles.
  • a typical electrostatic printing proces 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 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 thermolastic resin powder, which is held electrostatically 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.
  • thermoplastic resin powder A proces of electrostatic printing in which the thermoplastic resin powder is fused directly to the surface of the stratum is described in US. Patents 3,052,539 and 3,052,540, both to H. G. Greig.
  • the recording elements of this invention may be most effectively used in the process and .apparatus described in the Greig patents and represent improvements of the recording elements described in the Greig patents.
  • the recording element used in the process of the Greig patents comprises a backing sheet, such as paper coated with photoconductive white zinc oxide particles of high purity suspended in an electrically-insulating film-forming binder.
  • the photoconductive zinc oxide preferably has a surface photoconductivity higher than ohms square/watt/cm. when exposed to a Wavelength of about 3900 A. and is very pure, e.g., zinc oxide C.P. or U.S.P.
  • the electrically insulating film may be of a wide variety of substances. Synthetic resinous materials having high dielectric strengths are most desirable. These are known in the art as dielectric resins.
  • Examples are polyvinyl acetate, copolymers of vinyl chloride-vinyl acetate, polystyrene, styrene-butadiene copolymer resins, and silicone resins.
  • Other resin-like materials such as cellulose ethers and esters as well as natural resins may also be used.
  • coating of the recording element may further include one or more organic dyes which are capable of absorbing radiant energy in bands of wave lengths to which said zinc oxide particles are relatively insensitive and transferring said absorbed energy to said zinc oxide particles, thereby substantially increasing the total sensitivity of the photoconductive coating to light.
  • a photoconductive surface of increased light sensitivity will display an increased rate of discharge in the irradiated areas. This may also be termed an increased light decay rate.
  • the resins which are blended together may beaosen from the wide variety of resins conventionally used as the sole binder resins in electrostatic recording elements. Such resins are generally described in US. Patents 3,052,539 and 3,052,340.
  • the resins known as dielectric resins have high dielectric strengths. Among these resins are included acrylic ester polymers, rubber resins, polyester resins, polyvinyl acetate, copolymers of vinyl chloride-vinyl acetate, polystyrene, silicone resins, cellulose ethers, cellulose esters and shellac.
  • Other suitable resins as Well as some particularly desirable blends for the practice of this invention will be discussed in greater detail hereinafter.
  • the percent haze is also calculated for the uncoated glass slide and the resulting percent haze is substracted from the percent haze .of the coated slide to give the actual percent haze of the film.
  • the percent haze given will be the corrected or actual percent haze of the film.
  • similar coated slides are prepared in which each of the two resins of the blend is used alone in an amount equal to total weight of the blend and percent haze is determined in each case.
  • the film of partially incompatible blend will show a higher haze percentage than films in which the component resins are used alone.
  • the film of the blend should appear to be continuous to the naked eye. There should be an absence of macroscopic discontinuities in the film.
  • the haze on the slide containing the blend will be visible to the naked eye, giving the coating a milky white or frosted appearance.
  • the haze percentage of dry films of the blend are preferably greater than 1% and less than 48%. At haze percentages over 48%, macroscopic discontinuities begin to appear in many cases.
  • the photoconductor is preferably zinc oxide of the type described in U.S. Patent 3,052,539
  • other finely divided conventional photoconductors may be used such as the oxides of antimony, aluminum, bismuth, cadmium, mercury, molybdenum and lead; the iodides, selenides, sulfides or tellurides of these metals including zinc; selenium; arsenic trisulfide; lead chromate and cadmium arsenide.
  • the coating may also contain other conventional additives such as the waxes e.g., parafiin and carnauba and the plasticizers described in U.S. Patent 3,052,539 as well as sensitizing dyes such as those described in U.S. Patent 3,052,539.
  • waxes e.g., parafiin and carnauba
  • plasticizers described in U.S. Patent 3,052,539
  • sensitizing dyes such as those described in U.S. Patent 3,052,539.
  • the resins is a polyester resin comprising the condensation polymerization product of ethylene glycol and terephthalc acid.
  • Excellent results may be effected by blending, as a first component, polyester resins which are polymers of ethylene terephthalate containing ethylene sebacate or ethylene adipate, preferably in minor amounts. (These polymers are produced by the condensation polymerization of ethylene glycol, terephthalic acid and sebacic or adipic acid), with, as a second component, polyester resins described in U.S. Patent 2,965,613 to Milone et al.
  • polyester resins of this type are commercially available under the Vitel trademark, polyester resin Vitel PE207 being equivalent to the first component in the blend and polyester resins Vitel PE100 and Vitel PE200 being equivalent to the second component in the blend.
  • polyester resins also give very good results when blended with other resins so as to be partially incompatible.
  • blends of the polyester resins of Patent No. 2,965,613 having the higher ethylene isophthalate-content polyester resins as a second component with acrylic ester polymers as the first component have been found to be very good embodiments of this invention.
  • acrylic ester polymers are preferably homopolymers and copolymers of esters of acrylic or methacrylic acids with lower alkyl alcohols.
  • blends of the higher ethylene terephthalate-content polyester resins or the ethylene terephthalate-ethylene sebacate or adipate as a first component and styrene-butadiene rubber resins as a second component have been quite effective as have blends of acrylic ester copolymers and styrenebutadiene rubber resins.
  • Example 1 The following mixture is ball milled to a smooth consistency:
  • Lucite 2046 (a copolymer of n-butylmethacrylate and 50% isobutyl methacrylate) 7.3 Pliolite S-7 (a rubber resin consisting of a copolytrier of styrene and 30% butadiene) 1.8 Zinc oxide (Photox 801) 45.1 Toluene 41.0 Rose Bengal dye (a 0.12% solution in methanol) 6.0 Methylene Blue dye (a 0.12% solution in methanol) 2.0 Iosol Yellow dye (a 0.24% solution in toluene) 4.0
  • the mixture is then coated on white bond paper using a doctor roller and the coated paper is air dried to a dry film thickness of 0.5 mil.
  • each of the three sheets is negatively charged and exposed to a light image and then developed to form a copy.
  • the sheet containing the blend of the two resins gives copies having images of equivalent intensity to those formed on the sheet containing Pliolite S7 alone but in almost onefourth the exposure time.
  • the sheet containing the blend gives images of equivalent intensity to those containing Lucite 2046 alone in less than one-half the exposure time.
  • compositions of the above resins in which the dyes and the zinc oxide have been eliminated are prepared. They have the following compositions:
  • Percent of the total light scattered Percent of the total light transmitted the percent haze is determined in case to be:
  • Example 2 Following the procedure of Example 1, a coated copying paper is prepared from the following composition:
  • the sheet containing a coating of the blend gives copies having images of equivalent intensity to those formed on the sheets containing coating of either resin alone in about /a the exposure time.
  • films on glass slides are prepared of the blend and of the component resins individually by eliminating the zinc oxide and the dyes from the compositions of this example.
  • Example 3 Following the procedure of Example 1, a coated copying paper is prepared from the following composition:
  • the haze in the blend film is also markedly visible to the naked eye.
  • Example 4 Following the procedure of Example 1, a coated copying paper is prepared from the following composition:
  • sheets are prepared with copolyester and polymethylmeth-acrylate alone in place of the resin blend.
  • the sheets coated with compositions containing the blend give copies having images of equivalent intensity to those formed on the sheets containing coatings of either resin alone in about /2 the exposure time.
  • the haze in the film of the blend is also markedly visible to the naked eye.
  • Example 5 Fol-lowing the procedure of Example 1, a coated copying paper is prepared from the following composition:
  • the haze .in the film of the blend is also markedly visible to the naked eye.
  • a recording element for electrostatic printing comprising a base sheet carrying a photoconductive insulating layer comprising zinc oxide suspended in an electrically insulating film-forming vehicle which comprises a blend of two partially incompatible resins in such proportions that said resins are partially incompatible with each other to the extent that a dry film of the blend alone deposited from an organic solution has a greater haze than films of equivalent thickness containing either of the resins alone in an amount equal to the total resin content of the blend while having an absence of macroscopic discontinuities, said blend of resin being of the group (A) a blend of polyesters, wherein one of the resins is a polyester comprising the condensation polymerization product of ethylene glycol and an acid component comprising at least 25% of the total acid compound weight of isophthalic acid and the remainder terephthalic acid, and the other resin is a polyester comprising the condensation polymerization product of ethylene glycol and an acid component comprising terephthalic acid and sebacic acid, (B) a blend wherein one of the resins is a
  • one of the resins is a copolyester comprising ethylene terephthalate and ethylene isophthalate, at least one part of ethylene isophthalate being present in the copolyester for each 3 parts of ethylene terephthalate, and the other resin is poly n-butylmethacrylate) 5.
  • one of the resins is a copolyester of ethylene terephthalate and ethylene sebacate and the other resin is a copolymer of styrene and butadiene.
  • one of the resins is a copolymer of n-butylmethacrylate and isobutylmethacryl-ate and the other resin is a copolymer of styrene and butadiene.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Polymers & Plastics (AREA)
  • Medicinal Chemistry (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Photoreceptors In Electrophotography (AREA)
  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
US343152A 1964-02-06 1964-02-06 Recording elements for electrostatic printing Expired - Lifetime US3378370A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US343152A US3378370A (en) 1964-02-06 1964-02-06 Recording elements for electrostatic printing
GB3327/65A GB1077053A (en) 1964-02-06 1965-01-26 Recording elements for electrostatic printing
FR3420A FR1424079A (fr) 1964-02-06 1965-01-27 élément d'enregistrement pour impression électrostatique
BE659027D BE659027A (US20070167544A1-20070719-C00007.png) 1964-02-06 1965-01-29
ES0309018A ES309018A1 (es) 1964-02-06 1965-02-05 Un metodo de producir un elemento de registro para impresion electrostatica.
DE19651497157 DE1497157A1 (de) 1964-02-06 1965-02-05 Aufzeichnungstraeger fuer elektrostatische Druckverfahren und Verfahren zur Herstellung desselben
CH157965A CH438946A (fr) 1964-02-06 1965-02-05 Procédé de préparation d'un élément d'enregistrement pour impression électrostatique
NL6501531A NL6501531A (US20070167544A1-20070719-C00007.png) 1964-02-06 1965-02-08

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US343152A US3378370A (en) 1964-02-06 1964-02-06 Recording elements for electrostatic printing

Publications (1)

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US3378370A true US3378370A (en) 1968-04-16

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US343152A Expired - Lifetime US3378370A (en) 1964-02-06 1964-02-06 Recording elements for electrostatic printing

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US (1) US3378370A (US20070167544A1-20070719-C00007.png)
BE (1) BE659027A (US20070167544A1-20070719-C00007.png)
CH (1) CH438946A (US20070167544A1-20070719-C00007.png)
DE (1) DE1497157A1 (US20070167544A1-20070719-C00007.png)
ES (1) ES309018A1 (US20070167544A1-20070719-C00007.png)
GB (1) GB1077053A (US20070167544A1-20070719-C00007.png)
NL (1) NL6501531A (US20070167544A1-20070719-C00007.png)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3540886A (en) * 1968-06-25 1970-11-17 Desoto Inc Acidic photoconductive resin binders
US3652271A (en) * 1967-09-01 1972-03-28 Addressograph Multigraph Photoelectrostatic recording member
US3857708A (en) * 1968-04-26 1974-12-31 Agfa Gevaert Zinc oxide-binder medium containing microscopic cavities
US3985560A (en) * 1969-08-21 1976-10-12 Xerox Corporation Migration imaging member with fusible particles
FR2305759A1 (fr) * 1975-03-26 1976-10-22 Xerox Corp Procede de fabrication de couches photoconductrices a copolymere heterogene et nouveaux produits ainsi obtenus
US4284699A (en) * 1977-02-14 1981-08-18 Eastman Kodak Company Polyester binder component in multilayer photoconductive element
US4301224A (en) * 1979-07-13 1981-11-17 Ricoh Co., Ltd. Electrophotographic element with a combination of binder resins
US4418135A (en) * 1982-09-22 1983-11-29 Allied Corporation Thermally-stable, infrared-sensitive zinc oxide electrophotographic compositions element and process
US4855202A (en) * 1987-03-10 1989-08-08 Canon Kabushiki Kaisha Electrophotographic photosensitive member

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2008265B (en) * 1977-10-07 1982-06-23 Canon Kk Image holding member for holding electrostatic images or toner images
JPS6022349B2 (ja) * 1977-10-15 1985-06-01 キヤノン株式会社 電子写真感光体
NL8100163A (nl) * 1981-01-15 1982-08-02 Oce Nederland Bv Herhaaldelijk bruikbaar electrofotografisch element en werkwijze voor de vervaardiging van dat element.

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2959481A (en) * 1958-12-18 1960-11-08 Bruning Charles Co Inc Electrophotographic recording member and process of producing same
US2990279A (en) * 1956-09-25 1961-06-27 Rca Corp Electrostatic printing
US3079253A (en) * 1957-06-19 1963-02-26 Rca Corp Method of electrophotography employing a heat glossing composition
US3121006A (en) * 1957-06-26 1964-02-11 Xerox Corp Photo-active member for xerography
US3132941A (en) * 1960-12-02 1964-05-12 Eastman Kodak Co Superior binders for photoconductive layers containing zinc oxide
US3152895A (en) * 1962-03-14 1964-10-13 T F Washburn Company Coating composition for the production of electrophotographic recording members
US3159483A (en) * 1959-07-14 1964-12-01 Azoplate Corp Process for the preparation of electrophotographic reversed images
US3268332A (en) * 1962-05-25 1966-08-23 Itek Corp Electrophotographic element

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2990279A (en) * 1956-09-25 1961-06-27 Rca Corp Electrostatic printing
US3079253A (en) * 1957-06-19 1963-02-26 Rca Corp Method of electrophotography employing a heat glossing composition
US3121006A (en) * 1957-06-26 1964-02-11 Xerox Corp Photo-active member for xerography
US2959481A (en) * 1958-12-18 1960-11-08 Bruning Charles Co Inc Electrophotographic recording member and process of producing same
US3159483A (en) * 1959-07-14 1964-12-01 Azoplate Corp Process for the preparation of electrophotographic reversed images
US3132941A (en) * 1960-12-02 1964-05-12 Eastman Kodak Co Superior binders for photoconductive layers containing zinc oxide
US3152895A (en) * 1962-03-14 1964-10-13 T F Washburn Company Coating composition for the production of electrophotographic recording members
US3268332A (en) * 1962-05-25 1966-08-23 Itek Corp Electrophotographic element

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3652271A (en) * 1967-09-01 1972-03-28 Addressograph Multigraph Photoelectrostatic recording member
US3857708A (en) * 1968-04-26 1974-12-31 Agfa Gevaert Zinc oxide-binder medium containing microscopic cavities
US3540886A (en) * 1968-06-25 1970-11-17 Desoto Inc Acidic photoconductive resin binders
US3985560A (en) * 1969-08-21 1976-10-12 Xerox Corporation Migration imaging member with fusible particles
FR2305759A1 (fr) * 1975-03-26 1976-10-22 Xerox Corp Procede de fabrication de couches photoconductrices a copolymere heterogene et nouveaux produits ainsi obtenus
US4284699A (en) * 1977-02-14 1981-08-18 Eastman Kodak Company Polyester binder component in multilayer photoconductive element
US4301224A (en) * 1979-07-13 1981-11-17 Ricoh Co., Ltd. Electrophotographic element with a combination of binder resins
US4418135A (en) * 1982-09-22 1983-11-29 Allied Corporation Thermally-stable, infrared-sensitive zinc oxide electrophotographic compositions element and process
US4855202A (en) * 1987-03-10 1989-08-08 Canon Kabushiki Kaisha Electrophotographic photosensitive member

Also Published As

Publication number Publication date
ES309018A1 (es) 1965-07-01
BE659027A (US20070167544A1-20070719-C00007.png) 1965-07-29
NL6501531A (US20070167544A1-20070719-C00007.png) 1965-08-09
CH438946A (fr) 1967-06-30
GB1077053A (en) 1967-07-26
DE1497157A1 (de) 1969-05-22

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