Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C255/00—Carboxylic acid nitriles
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09B—ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES, e.g. PIGMENTS; MORDANTS; LAKES
  • C09B23/00—Methine or polymethine dyes, e.g. cyanine dyes
  • C09B23/14—Styryl dyes
  • C09B23/143—Styryl dyes the ethylene chain carrying a COOH or a functionally modified derivative, e.g.-CN, -COR, -COOR, -CON=, C6H5-CH=C-CN
• • 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
  • G03G5/0601—Acyclic or carbocyclic compounds
  • G03G5/0612—Acyclic or carbocyclic compounds containing nitrogen
• • 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
  • G03G5/0601—Acyclic or carbocyclic compounds
  • G03G5/0618—Acyclic or carbocyclic compounds containing oxygen and nitrogen
• • 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
  • G03G5/0664—Dyes
  • G03G5/0666—Dyes containing a methine or polymethine group
  • G03G5/0672—Dyes containing a methine or polymethine group containing two or more methine or polymethine groups

Definitions

• the process of xerography employs an electrophotographic element comprising a support material bearing a coating of a normally insulating material whose electrical resistance varies with the amount of incident electromagnetic radiation it receives during an imagewise exposure.
• the element commonly termed a photoconductive element, is first given a uniform surface charge, generally in the dark after a suitable period of dark adaptation. It is then exposed to a pattern of actinic radiation which has the effect of differentially reducing the potential of this surface charge in accordance with the relative energy contained in various parts of the radiation pattern.
• the differential surface charge or electrostatic latent image remaining on the electrophotographic element is then made visible by contacting the surface with a suitable electroscopic marking material.
• marking material or toner whether contained in an insulating liquid or on a dry carrier, can be deposited on the exposed surface in accordance with either the charge pattern or discharge pattern as desired. Deposited marking material can then be either permanently fixed to the surface of the sensitive element by known means such as heat, pressure, solvent vapor, or the like, or transferred to a second element to which it can similarly be fixed. Likewise, the electrostatic charge pattern can be transferred to a second element and developed there.
• Various photoconductive insulating materials have been employed in the manufacture of electrophotographic elements. For example, vapors of selenium and vapors of selenium alloys deposited on a suitable support and particles of photoconductive zinc oxide held in a resinous, film-forming binder have found wide application in the present-day document copying applications.
• compositions when coated as a film or layer on a suitable support, also yield an element which is reusable; that is, it can be used to form subsequent images after residual toner from prior images has been removed by transfer and/or cleaning.
• an element which is reusable that is, it can be used to form subsequent images after residual toner from prior images has been removed by transfer and/or cleaning.
• a, a-bis(aminobenzylidene )aryldiacetonitriles as photoconductors.
• These materials can be substituted in various positions by any one or more of several substituents.
• the arylene nuclei can be substituted with alkyl, aryl, halogen, alkoxy or aryloxy groups while the amino moiety can have alkyl or aryl substituents.
• the methyl carbons of the benzylidene moieties can be substituted by aryl or alkyl groups.
• the preferred a, a'-bis(aminobenzylidene )aryldiaceton itrile photoconductors of the invention are characterized by the following formula:
• alkylaminoakyl e.g. methylaminopropyl
• methylaminoethyl, etc. and also including dialkylaminoalkyl e. g. diethylaminoethyl,
• arylaminoalkyl e.g., phenylaminoalkyl, diphenylaminoalkyl, N-phenyl-N-ethylaminopentyl, N-phenyl-N- ethylaminohexyl, naphthylaminomethyl, etc.
• nitroalkyl e.g., nitrobutyl, nitroethyl, nitropentyl, etc.
• cyanoalkyl e.g., cyanopropyl, cyanobutyl, cyanoethyl
• haloalkyl e.g., chloromethyl, bromopentyl, chlorooctyl,
• an aryl group e.g., phenyl, naphthyl, anthryl, fluorenyl, etc., including a substituted aryl group such as a. alkoxyaryl, e.g., ethoxyphenyl, methoxyphenyl, propoxynaphthyl, etc.,
• aryloxyaryl e.g., phenoxyphenyl, naphthoxyphenyl,
• aminoaryl e.g., aminoanthryl, etc.
• hydroxyaryl e.g., hydroxyphenyl, hydroxynaphthyl
• alkylaminoaryl e.g., methylaminophenyl
• arylaminoaryl e.g., phenylaminophenyl, diphenylaminophenyl, N-phenyl-N-ethylaminophenyl, naphthylaminophenyl, etc.
• nitroaryl e.g., nitrophenyl, nitronaphthyl, nitroanthryl,
• cyanoaryl e.g., cyanophenyl, cyanonaphthyl
• haloaryl e.g., chlorophenyl, bromophenyl,
• alkaryl e.g., tolyl, ethylphenyl, propyl, naphthyl, etc.;
• R and R each represent any of the substituents set forth above for R R R and R above and also can be hydrogen;
• R R and R each represent any of the substituents set forth above for R, and R and also can be any of the following:
• alkoxy group having one to 18 carbon atoms e.g., methoxy, ethoxy, propoxy, butoxy, etc.
• aryloxy group e.g., phenoxy, naphthoxy, etc.
• halogen such as chlorine, bromine, fluorine or iodine.
• Typical compounds which belong to the herein described general class of photoconductive materials include the following listed Table I below.
• Electrophotographic elements of the invention can be prepared with the photoconducting compounds of the invention in the usual manner, i.e., by blending a dispersion or solution of a photoconductive compound together with a binder, when necessary or desirable, and coating or forming a selfsupporting layer with the photoconductor-containing materials. Mixtures of the photoconductors described herein can be employed. Likewise, other photoconductors known in the art such as those described in Light, Belgian Pat. No. 705,117 dated Apr. 16, 1968 can be combined with the present photoconductors. In addition, supplemental materials useful for changing the spectral sensitivity or electrophotosensitivity of the element can be added to the composition of the element when it is desirable to produce the characteristic effect of such materials.
• the photoconductive layers of the invention can also be sensitized by the addition of effective amounts of sensitizing compounds to exhibit improved electrophotosensitivity.
• Sensitizing compounds useful with the photoconductive compounds of the present invention can be selected from a wide variety of materials, including such materials as pyrylium dye salts including thiapyrylium dye salts and selenapyrylium dye salts disclosed in VanAllan et'al. U.S. Pat. No.
• fluorenes such as 7,12-dioxo-l 3-dibenzo (a,h)fluorene, 5,10- dioxo-4a,1 l-diazobenzo(b)-fluorene, 3,13-dioxo-7-oxadibenzo (b,g)fluroene, and the like; aggregate-type sensitizers of the type described in Light, Belgian Pat. No. 705,117, dated Apr. 16, 1968; aromatic nitro compounds of the kinds described in U.S. Pat. No. 2,610,120; anthrones like those disclosed in U.S. Pat. No. 2,670,284; quinones, U.S. Pat. No.
• the sensitizers preferred for use with the compounds of this invention are selected from pyrylium salts including selenapyrylium salts and thiapyrylium salts, and cyanine dyes including carbocyanine dyes.
• sensitizing compound is employed with the binder and organic photoconductor to form a sensitized electrophotographic element
• sensitizer or the effect of the sensitizer may, however, be employed consistent with the practice of this invention.
• no sensitizing compound is required to give photoconductivity in the layers which contain the photoconducting substances, therefore, no sensitizer is required in a particular photoconductive layer.
• the sensitizer is preferred.
• the amount of sensitizer than can be added to a photoconductor-incorporating layer to give effective increases in speed can vary widely. The optimum concentration in any given case will vary with the specific photoconductor and sensitizing compound used.
• an appropriate sensitizer is added in a concentration range from about 0.0,001 to about 30 percent by weight based on the weight of the film-forming coating composition.
• a sensitizer is added to the coating composition in an amount by weight from about 0.005 to about 5.0 percent by weight of the total coating composition.
• Preferred binders for use in preparing the present photoconductive layers are film-forming, hydrophobic polymeric binders having fairly high dielectric strength which are good electrically insulating film-forming vehicles.
• Natural resins including gelatin, cellulose ester derivatives such as alkyl esters of carboxylated cellulose, hydroxy ethyl cellulose, carboxy methyl cellulose, carboxy methyl hydroxy ethyl cellulose, etc.;
• Vinyl resins including a. polyvinyl esters such as a vinyl acetate resin, a copolymer of vinyl acetate and crotonic acid, a copolymer of vinyl acetate with an ester of vinyl alcohol and a higher aliphatic carboxylic acid such as lauric acid or stearic acid, polyvinyl stearate, a copolymer of vinyl acetate and maleic acid, a poly(vinylhaloarylate) such as poly(vinylm-bromobenzoate-covinyl acetate), 2 terpolymer of vinyl butyral with vinyl alcohol and vinyl acetate, etc.;
• polyvinyl esters such as a vinyl acetate resin, a copolymer of vinyl acetate and crotonic acid, a copolymer of vinyl acetate with an ester of vinyl alcohol and a higher aliphatic carboxylic acid such as lauric acid or stearic acid, polyvinyl stea
• vinyl chloride and vinylidene chloride polymers such as a poly(vinylchloride), a copolymer of vinyl chloride and vinyl isobutyl ether, a copolymer of vinylidene chloride and acrylonitrile, a terpolymer of vinyl chloride, vinyl acetate and vinyl alcohol, poly(vinylidene chloride) a terpolymer of vinyl chloride, vinyl acetate and maleic anhydride, a copolymer of vinyl chloride and vinyl acetate, etc.;
• styrene polymers such as polystyrene, a nitrated polystyrene, a copolymer of styrene and monoisobutyl maleate, a copolymer of styrene with methacrylic acid, a
• copolymer of styrene and butadiene a copolymer of dimethylitaconate and styrene, polymethylstyrene, etc.;
• methacrylic acid ester polymers such as a poly(alkylmethacrylate), etc.
• polyolefins such as chlorinated polyethylene, chlorinated polypropylene, poly(isobutylene), etc.
• poly(vinyl acetals) such as poly(vinyl butyral), etc.
• Polycondensates including a. a polyester of 1,3-disulfobenzene and 2,2-bis(4-hydroxyphenyl)propane;
• polyester of pentaerythritol and phthalic acid e. polyester of pentaerythritol and phthalic acid
• polycarbonates including polythiocarbonates such as the polycarbonate of 2,2-bis( 4-hydroxyphenyl)propane;
• Alkyd resins including styrene-alkyd resins, siliconealkyd resins, soya-alkyd resins, etc.;
• Solvents useful for preparing coating compositions with the photoconductor of the present invention can include a wide variety of organic solvents for the components of the coating composition.
• Typical solvents include:
• aromatic hydrocarbons such as benzene, naphthalene, etc., including substituted aromatic hydrocarbons such as toluene, xylene, mesitylene, etc;
• ketones such as acetone, 2-butanone, etc.
• halogenated aliphatic hydrocarbons such as methylene chloride, chloroform, ethylene chloride, etc.
• ethers including cyclic ethers such as tetrahydrofuran, ethylether;
• the photoconductive substance is present in an amount equal to at least about 1 weight percent of the coating composition.
• the upper limit in the amount of photoconductive material present can be widely varied in accordance with usual practice. It is normally required that the photoconductive material be present in an amount ranging from about 1 weight percent of the coating composition to about 99 weight percent of the coating composition.
• a preferred weight range for the photoconductive material in the coating composition is from about 10 weight percent to about 60 weight percent.
• Coating thicknesses of the photoconductive composition on a support can vary widely. Normally, a wet coating thickness in the range of about 0.001 inch to about 0.01 inch is useful in the practice of the invention. A preferred range of coating thickness is from about 0.002 inch to about 0.006 inch before drying although such thicknesses can vary widely depending on the particular application desired for the electrophotographic element.
• Suitable supporting materials for the photoconductive layers of the present invention can include any of the electrically conducting supports, for example, various conducting papers; aluminum-paper laminates; metal foils, such as aluminum foil, zinc foil, etc.; metal plates such as aluminum, copper, zinc, brass, and galvanized plates; vapor deposited metal layers such as silver, nickel or aluminum on conventional film supports such as cellulose acetate, poly(ethylene terephthalate), polystyrene and the like conducting supports.
• An especially useful conducting support can be prepared by coating a transparent film support material such as poly(ethylene terephthalate) with a layer containing a semiconductor dispersed in a resin.
• a suitable conducting coating can be prepared from the sodium salt of a carboxyester lactone of a maleic anhydride-vinyl acetate copolymer, cuprous iodide and the like, Such conducting layers and methods for their optimum preparation and use are disclosed in US. Pat. Nos. 3,007,901, 3,245,833 and 3,267,807.
• compositions of the present invention can be employed in photoconductive elements useful in any of the well known electrophotographic processes which require photoconducglycol,
• tive layers are tive layers.
• One such process is the xerographic process. in a process of this type, an electrophotographic element held in the dark, is given a blanket positive or negative electrostatic charge as desired by placing it under a corona discharge to give a uniform charge to the surface of the photoconductive layer. This charge is retained by the layer owing to the substantial dark insulating property of the layer, i.e., the low conductivity of the layer in the dark.
• the electrostatic charge formed on the surface of the photoconductive layer is then selectively dissipated from the surface of the layer by imagewise exposure to light by means of a conventional exposure operation such as for example, by a contact-printing technique, or by lens projection of an image, or reflex or bireflex techniques and the like, to thereby form a latent electrostatic image in the photoconductive layer.
• Exposing the surface in this manner forms a pattern of electrostatic charge by virtue of the fact that light energy striking the photoconductor causes the electrostatic charge in the light struck areas to be conducted away from the surface in proportion to the illuminance on a particular area.
• the charge pattern produced by exposure is then developed or transferred to another surface and developed there, i.e., either the charged or uncharged areas rendered visible, by treatment with a medium comprising electrostatically responsive particles having optical density.
• the developing electrostatically responsive particles can be in the form of a dust, or powder and generally comprise a pigment in a resinous carrier called a toner.
• a preferred method of applying such a toner to an electrostatic image for solid area development is by the use of a magnetic brush. Methods of forming and using a magnetic brush toner applicator are described in the following U.S. Pat. Nos.
• Liquid development of the latent electrostatic image may also be used.
• the developing particles are carried to the image-bearing surface in an electrically insulating liquid carrier.
• Methods of development of this type are widely known and have been described in the patent literature, for example, U.S. Pat. No. 2,297,691 and in Australian Pat. No. 212,315.
• dry developing processes the most widely used method of obtaining a permanent record is achieved by selecting a developing particle which has as one of its components a low-melting resin.
• Heating the powder image then causes the resin to melt or fuse into or on the element.
• the powder is, therefore, caused to adhere permanently to the surface of the photoconductive layer.
• a transfer of the charge image or powder image formed on the photoconductive layer can be made to a second support such as paper which would then become the final print after developing and fusing or fusing respectively.
• compositions of the present invention can be used in electrophotographic elements having many structural variations.
• the photoconductive composition can be coated in the form of single layers or multiple layers on a suitable opaque or transparent conducting support.
• the layers can be contiguous or spaced having layers of insulating material or other photoconductive material between layers or overcoated or interposed between the photoconductive layer or sensitizing layer and the conducting layer. It is also possible to adjust the position of the support and the conducting layer by placing a photoconductor layer over a support and coating the exposed face of the support or the exposed or overcoated face of the photoconductor with a conducting layer. Configurations differing from those contained in the examples can be useful or even preferred for same or different application for the electrophotographic element.
• Organic photoconductor 0.5 g. Polymeric binder 1.5 g. Sensitizer 0.02 g. Methylene chloride 1 1.7 ml.
• compositions are coated at a wet thickness of 0.004 inch on a conducting layer comprising the sodium salt of a carboxyester lactone, such as described in U.S. Pat. No. 3,120,028, which in turn is coated on a cellulose acetate film base.
• the coating blocks are maintained at a temperature of F.
• These electrophotographic elements are charged under a positive corona source until the surface potentials, as measured by an electrometer probe, reach between about 600 volts. They are then subjected to exposure from behind a stepped density gray scale to a 3,000 K. tungsten source.
• the exposure causes reduction of the surface potential of the portion of the element under each step of the gray scale from its initial potential, V0, to some lower potential, V, whose exact value depends on the actual amount of exposure in meter-candle-second received by the area.
• the results of the measurements are plotted on a graph of surface potential V vs. log exposure for each step.
• the speed is the numerical expression of 10 multiplied by the reciprocal of the exposure in meter-candle-seconds required to reduce the 500 to 600 volt charged surface potential to volts above 0 volt.
• the reduction of the surface potential to 100 volts or below is significant in that it represents a requirement for suitable broad area development ofa latent image.
• This speed at 100 volts is a measure of the ability to produce and henceforth to develop or otherwise utilize the charge image, higher speeds requiring less illumination to produce a usable charge image.
• the surface potential does not drop to, or below, 100 volts and no speed value can be assigned. This is also the case when a compound is present in the composition but is ineffective as a photoconductor.
• the speeds of the various photoconductive compositions are shown in Table 11 below.
• the sensitizers used are referred to below as follows:
• Photoconduclor 025 g. Polymeric binder Vitel LOO g. Sensitizer 0.0] g. Dichloromelhane 9.60 g.
• the coating block is maintained at a temperature of 90 F. until the solvent is removed.
• the surface of the photoconductive layer so prepared is charged to a potential of about +600 volts under a corona charger.
• the layer is then covered with a transparent sheet bearing a pattern of opaque and light-transmitting areas and exposed to the radiation from an incandescent lamp with an illumination intensity of about 75 meter-candles for 12 seconds.
• the resulting electrostatic latent image is developed by cascading over the surface of the layer negatively charged black thermoplastic toner particles on glass bead carriers.
• Table V The quality of the images reproduced using the various photoconductors described herein are set forth in the following Table V.
• R R R and R are each selected from the group consisting of an aryl group and an alkyl group
• R and R are each selected from the group consisting of an alkyl group, an aryl group and a hydrogen atom and R R and R are each selected from the group consisting of an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a halogen atom and a hydrogen atom.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Health & Medical Sciences (AREA)
• Emergency Medicine (AREA)
• Photoreceptors In Electrophotography (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=25362798

Family Applications (1)

Country Status (6)

Cited By (5)

Families Citing this family (1)

Citations (1)

• 0
  • BE BE758335D patent/BE758335A/fr unknown
• 1969
  • 1969-11-04 US US874016A patent/US3653887A/en not_active Expired - Lifetime
• 1970
  • 1970-10-05 CA CA094772A patent/CA929167A/en not_active Expired
  • 1970-10-28 FR FR7038858A patent/FR2071857A5/fr not_active Expired
  • 1970-10-30 GB GB5175870A patent/GB1319498A/en not_active Expired
  • 1970-11-03 DE DE19702054061 patent/DE2054061A1/de active Pending

Patent Citations (1)

Also Published As

Similar Documents