US3705032A - Electrophotographic materials - Google Patents

Electrophotographic materials Download PDF

Info

Publication number
US3705032A
US3705032A US851562A US3705032DA US3705032A US 3705032 A US3705032 A US 3705032A US 851562 A US851562 A US 851562A US 3705032D A US3705032D A US 3705032DA US 3705032 A US3705032 A US 3705032A
Authority
US
United States
Prior art keywords
electrophotographic
alkyd resin
hydroxyl value
charge
spectral
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
US851562A
Other languages
English (en)
Inventor
Satoru Honjo
Masaaki Takimoto
Seiji Matsumoto
Kuniko Kosuge
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.)
Fujifilm Holdings Corp
Original Assignee
Fuji Photo Film Co Ltd
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 Fuji Photo Film Co Ltd filed Critical Fuji Photo Film Co Ltd
Application granted granted Critical
Publication of US3705032A publication Critical patent/US3705032A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • G03G5/0592Macromolecular compounds characterised by their structure or by their chemical properties, e.g. block polymers, reticulated polymers, molecular weight, acidity
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40High-molecular-weight compounds
    • C08G18/42Polycondensates having carboxylic or carbonic ester groups in the main chain
    • C08G18/4205Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups
    • C08G18/4208Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups containing aromatic groups
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40High-molecular-weight compounds
    • C08G18/42Polycondensates having carboxylic or carbonic ester groups in the main chain
    • C08G18/4288Polycondensates having carboxylic or carbonic ester groups in the main chain modified by higher fatty oils or their acids or by resin acids
    • 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
    • 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
    • Y10S524/00Synthetic resins or natural rubbers -- part of the class 520 series
    • Y10S524/901Electrodepositable compositions
    • Y10S524/902Electrostatic spray

Definitions

  • the present invention relates to an electrophotographic material sensitized with spectral sensitizers and, in particular, relates to an electrophotographic material having a novel binder composition which is suitable for liquid development.
  • an electrophotographic material one prepared by establishing a photoconductive insulating layer having dispersed therein a finely-divided inorganic photoconductive material such as zinc oxide, cadmium sulfide, titanium dioixde, zinc sulfide, etc. in an insulating filmforming material on a flexible support, such as paper, is known.
  • binder compositions used in an electrophotographic material containing finely-divided inorganic photoconductors suitable for liquid developing processes include cured alkyd resins, polymethylmethacrylate, vinyl chloride/vinyl acetate copolymers, etc. All are insoluble in the liquid carrier of a liquid developer.
  • the cured alkyd resins have excellent advantages such as being capable of forming a flexible sensitive layer showing little tendency to curl; of dispersing an organic pigment; of being stable in organic solvents; and of permitting the use of inexpensive organic solvents, such as toluol or xylol, in coating operations.
  • the inventors have found that the decay characteristics of an electrostatic charge on an insulating layer in a liquid developer which has heretofore been less noted is one of the most important factors affecting image quality. In particular, in the case of reproducing a continuous tone image, it has been proven that a slow decay of the surface charge in a liquid developer is essential for high quality image reproduction.
  • the cured alkyd resins have been found satisfactory as a binder with respect to the decay characteristic in the developer.
  • Other resins which have hitherto been used as a binder form a hard coating and hence incorporation of plasticizers in a photoconductive coating containing such resins is ordinarily necessary to provide a photoconductive paper with an acceptable mechanical behavior.
  • Plastici-zer incorporation is sometimes accompanied by deterioration of the charge retention property in the liquid developer as well as a remarkable lowering of light sensitivity, resulting in an inferior material to those comprising alkyd resins.
  • the curing of alkyd resins has been carried out by using at least one of the organic peroxides such as methyl ethyl ketone-peroxide, benzoyl peroxide, etc. and heavy metal compounds such as naphthenates of cobalt, manganese, iron, zinc, lead, etc.
  • organic peroxides such as methyl ethyl ketone-peroxide, benzoyl peroxide, etc.
  • heavy metal compounds such as naphthenates of cobalt, manganese, iron, zinc, lead, etc.
  • the alkyd resin binder composition has been found to be accompanied with a serious problem in a coating spectrally sensitized with organic sensitizing dyes, in particular, with those sensitive to oxidation, while there arises no problem in a coating composition not containing spectral sensitizers.
  • the sensitizers are gradually decomposed in the presence of a catalyst such as cobalt naphthenate. The decomposition seems to proceed considerably at the curing step of the resin, and in particular, sensitizers such as cyanine, merocyanine and xanthine dyes have been found weak to oxidation, and coatings containing such dyes faded rapidly during storage.
  • An electrophotographic material suitable for the reproduction of continuous tone images comprises an electrophotographic layer on a support, the electrophotographic layer comprising 'a finely-divided inorganic photoconductor, one or more spectral sensitizing dyes and an insulating film forming material.
  • the insulating film forming material comprises an alkyd resin cured with a polyisocyanate compound.
  • the alkyd resin must contain to 50% by weight of an aromatic dib'asic carboxylic acid, and must have a hydroxyl value within the range 10 to 100.
  • the polyisocyanate compound is contained in an amount within the range 1.2 to 8 times the equivalent amount which corresponds to the hydroxyl value of the alkyd resin.
  • one object of the present invention is to provide an electrophotographic material suitable for reproduction of continuous tone images, and, in particular, to provide an electrophotographic material suitable for a liquid developing process with an excellent charge retention property in many insulating organic liquids.
  • a further object of the present invention is to disclose a novel binder composition for a finely-divided inorganic photoconductor which is spectrally sensitized.
  • the present inventors have solved all the above-cited various problems by using polyisocyanate compounds for the curing of alkyd resins.
  • This invention relates to a method of forming an electrophotographic material and the material per se comprising a photoconductive insulating coating provided on a suitable support, said coating comprising a finely-divided inorganic photoconductor material, spectral sensitizer thereof, and an electrically insulating film-forming material, which is characterized 'by that said insulating filmforming material comprises alkyd resin hardened (cured) by polyisocyanate compound, said alkyd resin containing 10 to 50% by weight of phthalic or isophthalie acid, having a hydroxyl value between 10 to 100, said polyisocyanate compound being added in an amount 1.2 to 8 times as much as the amount equivalent to said hydroxyl value, and the excessive amount of said isocyanate radical being reacted with moisture.
  • said insulating filmforming material comprises alkyd resin hardened (cured) by polyisocyanate compound, said alkyd resin containing 10 to 50% by weight of phthalic or isophthalie acid, having a hydroxyl value
  • the above electrophotographic sensitive material of the present invention gives a tone reproduction characteristic curve with a low gamma and a high sensitivity. Moreover, the change of these characteristics during storage is quite small.
  • Preferred alkyd resins used in the compositions of the invention are those which contain as the acid component in their polyester main chain aromatic dibasic acids such as phthalic or isophthalic acid, and as the alcohol component glycerin, pentaerythritol, sorbitol, ethylene glycol, etc.
  • Such polyester chains may be modified by monobasic aliphatic acids, saturated or unsaturated, which may, then, be further modified by styrene, or acryl esters.
  • polyester main chains do not substantially comprise aliphatic dibasic acids.
  • suitable alkyd resins include phthalic acid-glycerin polyesters modified by any one member selected from the group comprising drying oil fatty 'acids, non-drying oil fatty acids, drying oil fatty acids modified with styrene or with acrylic ester, phenolformaldehyde resin, rosin, etc.
  • polyisocyanate is used as a hardener for a polyester resin comprising drying oil fatty acid and polyhydric alcohol, whereby the speed of photore-sponse of the resulting electrophotographic coating is lowered as the amount of the polyisocyanate increases, and greatly affected by the acid value of the polyester resin.
  • polyisocyanate is used for a polyester containing the dibasic aromatic carboxylic acid, the characteristics are not substantially varied even if the large excess of polyisocyanate is used and also the acid value of polyester does not greatly affect the characteristics of the product.
  • alkyd resins can give electrophotographic coatings of similar light sensitivity provided that they contain aromatic dibasic acids such as phthalic or i-sophthalic acid in the range between 10 to 50% by Weight of the alkyd resin (as calculated by the content of the corresponding acid anhydrides) and that they have an acid value not higher than 25. Resins which have particularly high acid values are not desirable because of slow reaction speed with isocyanates, although they are practicable if the reaction is accelerated at a high temperature.
  • the hydroxyl value should be not higher than 100, desirably below 75, and must be above 10 for sufficient curing.
  • Polyesters with high hydroxyl values which have widely been used together with polyisocyanates to form polyurethane coatings or the like are not suitable for the present purpose since they would produce coatings with an intense tendency to curl, mainly because of their too high cross-linking densities, and their low content of aromatic dibasic acids.
  • dry development processes such as cascade, magnetic brush, or powder cloud development, satisfactory dark decay characteristics can be obtained with the use of polyisocyanate 1.2 to 1.5 times equivalent to the hydroxyl content.
  • Suitable polyisocyanates should have a low evaporation rate at ordinary temperatures.
  • a condensation product of 1 mol of trimethylol propane and 3 mol of tolylene diisocyanate (commercially available product: Desmodur L manufactured by Bayer Co., Ltd., Colonate L manufactured by Nippon Polyurethane Industrial Co., Ltd.) is typical.
  • Hexarnethylene diisocyanate, 4,4,4"triphenylmethane triisocyanate (Desmodur R of Bayer Co., Ltd), diphenylmethane-4,4'-diisocyanate (Desmodur M of Bayer Co., Ltd.), etc. can also be utilized.
  • the amount of these polyisocyanate compounds may be added 1.2 to 8 times the equivalent amount corresponding to the content of hydroxyl groups in the alkyd resin to be cured.
  • a large amount of isocyanate is necessary to provide an electrophotographic coating which exhibits a sufiiciently slow dark decay characteristic in an insulating non-polar liquid generally used as the carrier liquid of a liquid developer.
  • an insulating non-polar liquid generally used as the carrier liquid of a liquid developer.
  • more than twice the equivalent amount of a polyisocyanate is necessary to obtain a photoconductive coating which shows a dark decay rate in purified kerosene which is as slow as that in air. With a lesser amount than this, the dark decay rate is satisfactorily slow in air, but quite rapid in liquids such as kerosene.
  • the charge decay characteristic of an electrophotographic coating in a liquid developer depends not only on the composition thereof, but also on the insulating properties and dissolving power of the liquid developer.
  • a carrier liquid having a strong dissolving power accelerates charge decay.
  • purified kerosene is usually used to estimate the charge decay performance of various coatings and it has been proven that the behavior in kerosene corresponds well to those in actual liquid developers, though they sometimes contain stronger solvents such as cyclohexane and have a lower electrical resistance.
  • the slow charge decay in the developer is essential for the satisfactory reproduction of continuous tone image.
  • toner deposition proceeds preferentially from a high electrostatic field region independently of the use of a development electrode.
  • development proceeds at the edge of said area, and as toner deposition proceeds, the fill-in of the area into the inner region continues, since the deposited toner at the edge of the region neutralizes the charge thereon, thus pushing the high field region inside the solid area. If the charge of the latent image leaks away during such a filling-in process, the resulting image will show a sharp density gradient decreasing from the edge towards the inner portion of the area, instead of forming a uniform density image.
  • a bias voltage is applied to a development electrode facing the latent image with a close spacing, in such a manner that the field near the area having the maximum charge density in said latent image is substantially neutralized, thus preventing toner deposition at that area.
  • the charge decay rate of the image in the liquid developer is rapid, it is necessary to adjust the value of the bias voltage in a synchronized manner to correspondingly decrease with the decrease in the charge density in the image. This makes the apparatus complicated and causes various troubles during practice.
  • tone reproduction characteristic is very soft. This has been confirmed by an experiment using a liquid developer containing a toner having an average particle diameter near 0.2 to 0.311..
  • the electrophotographic sensitive material of the present invention When exposed to light, after being uniformly charged through an optical wedge, the electrophotographic sensitive material of the present invention yields a gamma of about 0.7 to 1.3 for a characteristic curve while the corresponding value for many conventional materials lies between 1.5 to 2.0 through similar processing.
  • the maximum optical density of the material prepared in accordance with the present invention is generally high, reaching 1.5 to 2.0.
  • 'y is determined from an average gradient of a tone reproduction curve which is drawn by plotting the refiection optical density of a developed wedge on the ordinate and log amount of exposure on the abscissa, whereby the length of the abscissa corresponding to the variation of times exposure and that of the ordinate corresponding to the optical density are taken to be equal, and defined as unit length.
  • a set of two parallel lines separated by one-tenth of the abovedefined unit length is drawn in such a manner that the tone reproduction curve is tangentially put between these lines, and the slope of the lines is defined as gamma.
  • the technique in the present invention is quite different from the known technical arts, and gives electrophotographic photoconductive coatings having excellent properties with the combination of alkyd resins and polyisocyanates.
  • the present resin composition has no harmful influence on sensitizing dyes, thus showing no change of sensitivity under a long period of storage. It imparts a higher efiiciency of spectral sensitization to the spectral sensitizer than other resin formulations. It is difficult to explain this high efficiency at present when theories have been given only for the interaction of carboxyl and hydroxyl groups in the resin with zinc oxide, since substantially the total amount of the hydroxyl groups originally present in the alkyd resin enter into condensation reaction with the isocyanate group to give a very low concentration of hydroxyl group in the final binder structure.
  • the binder of the present invention gives high sensitivity may be understood with the explanation that although the OH groups of the alkyd resin are decreased by the reaction with polyisocyanate, the NH- groups formed by the reaction of isocyanate with water may have a similar effect on ZnO as the OH group.
  • Spectral sensitizers to be utilized in the present invention include all of those hitherto well known in the art, typical of which are cyanine, merocyanine, oxonol, hemioxonol, benzilidene, xanthene, sulfophthalein, triphenyl methane coloring matters, etc.
  • cyanin, merocyanine and Xanthenes exhibit improved characteristics with the present formulation, since they are especially sensible to oxidation.
  • the ratio of inorganic photoconductive material and binder is generally in the range of above 50 parts and below 50 parts of the binder per 100 parts of the former material.
  • a special film forming method a high insulating film is obtained even with l to 0.5 part of the binder per 100 parts of the photoconductor.
  • the conventional process (1)a 0.2 part of cobalt naphthenate (cobalt metal content was mixed with 100 parts of photoconductive zinc oxide and 40 parts of styrene alkyd resin varnish (non-volatile concentration 50%, phthalic anhydride content 21%, styrene content 30%, hydroxyl value 45, acid value 5, xylol solvent) in toluene, and 0.02 part of Eryshrosine (trademark, manufactured by Ciba Co., Ltd., Swiss) dissolved in a small amount of methanol was added dropwise thereto. The resulting pink colored dispersion was coated on sheets of aluminized paper; one sheet was kept in a light tight thermostat held at 40 C.
  • both sheets were measured for spectral reflectance by means of an automatic recording spectrophotometer.
  • the heated sheet showed 62.5% reflectance at 544 mu on the basis of the magnesium oxide powder layer, while the latter sample showed only 57%.
  • (1)b A sensitive layer was prepared in the same manner as in (1)-a except that part of p-dimethylaminobenzylidene rhodanine replaced the Eryshrosine B and methyl Cellosolve was used as the solvent. After coating, this was heated at 40 C. for 16 hours to cure the resin.
  • the spectral reflectance curve is shown as curve a in the attached figure, which lacks in a clear absorption peak.
  • Curve b shows the spectral reflectance of the same layer allowed to stand in a dark place at room temperature for four months. This shows that the rhodanine dye is completely decomposed.
  • Relatively low reflectance values in the total visible region is attributed to a light coating weight and the effect of the aluminum layer of the support contributing to absorption.
  • the photosensitivity to blue light decreased to 40% of the original value during four months storage.
  • the blue light was given by using a blue filter passing light in the range of 380 to 510 me (no spectral sensitizer).
  • An electrophotographic material was prepared in a similar manner as (l)-a differing only in that cobalt naphthenate was omitted from the coating formulation.
  • This material exhibited a reflectance value of 57% at 544 m after 16 hours storage at 40 0., showing that the sensitizer hardly decomposed in the absence of cobalt naphthenate.
  • To confirm the harmful effect of cobalt salt there was carried out a more drastic thermal treatment of four hours storage at 60 C. with these two samples with the result that the coating containing cobalt naphthenate gave 66% reflectance, while the other showed no rise of reflectance.
  • the dark decay characteristics in kerosene of these drastically thermal-treated samples were measured, after complete dark-adaptation, by charging them electrostatically with a negative corona, and by wetting their surfaces with purified kerosene having a volume resistance higher than 8 10 ohms-cm.
  • the potential remaining factor of the one containing cobalt naphthenate was 87% while that of one free of it was only 40%.
  • the one not containing the hardening catalyst is not completely cured even by this thermal treatment, and the charge thereon leaks away rapidly in the liquid.
  • the temperature and moisture at the time of measurement was 22 C. and 60% RH.
  • the photosensitivity for the same blue light as before was 520 for 100 in the state of a., about a five times elevation of sensitivity being obtained for (l)-b.
  • the spectral reflection characteristic and photosensitivity were not changed after storage in a dark place for four months. Also, the potential decay in kerosene was (remaining) after one minute. In this example, 3.8 times the isocyanate of the theoretical equivalent (calculated from hydroxyl value) in alkyd resin is utilized.
  • EXAMPLE 2 The effect of the amount of polyisocyanate to be added to the binder composition on the electrophotographic characteristics will be described in this example.
  • Toluene was used as a solvent.
  • the adsorption sensitization for the zinc oxide surface was carried out by dispersing parts of dried zinc oxide in methanol and adding to the dispersion a methanol solution containing three different sensitizers having the following formulae:
  • SENSITIZER 2 hr 1'31 NaO 0 Br 0 Br COONa SENSITIZER 3 S O 3 NB TABLE 1 Number A B O Z110 100 100 100 Short type alkyd varnis 32 28 Desmodur L 6. 4 8 13. 3
  • Each mixture was coated on an aluminum surface of polyethylene terephthalate film (vacuum coated with aluminum to a dried thickness of 7 and dried in a thermostat at 40 C. for 16 hours.
  • the resulting sample was dark-adapted, and, after being charged negatively, exposed to light from standard light source A through an optical wedge, whereby four pieces of the same optical wedge were parallel placed, three of which were superimposed with blue, green and red filters, respectively, in order to obtain spectral tone reproduction characteristics.
  • the sheet was wetted with kerosene and developed for two minutes with a liquid developer comprising a commercially available offset printing ink in cyclohexane. Development was carried out with the use of a development electrode.
  • Kerosene is applied on the photoconductive surface with a pad so as to Wet the surface.
  • An electrophotographic material for use in a liquid developing environment having an electrophotographic layer comprising:
  • said film forming material consisting essentially of an alkyd resin cured in the presence of moisture with a polyisocyanate compound, said alkyd resin in its cured state containing from 10 to 50%, by weight, of an aromatic dibasic carboxylic acid and having a hydroxyl value ranging from 10 to 100, and said polyisocyanate compound being present in an amount ranging from 1.2 to 8 times the equivalent amount corresponding to the hydroxyl value of said uncured alkyd resin,
  • said film forming material having a 3-dimensional network within its molecular structure.
  • alkyd resin is a styrene-modified alkyd resin.
  • polyisocyanate is a condensation product of about 1 mole of trimethylol propane and 3 moles of tolyene diisocyanate.
  • alkyd resin contains as a constituent thereof a member selected from the group consisting of glycerin, pentaerythritol, sorbitol and ethylene glycol.
  • An electrophotographic material for use in a liquid developing environment having an electrophotographic layer comprising:
  • said film forming material consisting essentially of an alkyd resin cured in the presence of moisture with a polyisocyanate compound, said alkyd resin in its uncured state containing 10 to 50%, by weight, of an aromatic dibasic carboxylic acid and 'having a hydroxyl value of 100, said polyisocyanate compound being present in an amount of from 1.2 to 8 times the equivalent amount corresponding to the hydroxyl value of said alkyd resin, and the acid value of said uncured alkyd resin being below 25,
  • said film forming material having a 3-dimensional network within its molecular structure.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Photoreceptors In Electrophotography (AREA)
  • Polyurethanes Or Polyureas (AREA)
  • Paints Or Removers (AREA)
US851562A 1968-08-20 1969-08-20 Electrophotographic materials Expired - Lifetime US3705032A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5940068 1968-08-20

Publications (1)

Publication Number Publication Date
US3705032A true US3705032A (en) 1972-12-05

Family

ID=13112176

Family Applications (1)

Application Number Title Priority Date Filing Date
US851562A Expired - Lifetime US3705032A (en) 1968-08-20 1969-08-20 Electrophotographic materials

Country Status (7)

Country Link
US (1) US3705032A (de)
BE (1) BE737701A (de)
CA (1) CA918984A (de)
DE (1) DE1942383C3 (de)
FR (1) FR2016017A1 (de)
GB (1) GB1237036A (de)
NL (1) NL6912661A (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3969113A (en) * 1971-10-28 1976-07-13 Rank Xerox Ltd. Photosensitive binder layer for xerography containing titanium oxide and a cadmium pigment
US20050130253A1 (en) * 2003-12-16 2005-06-16 Kimberly-Clark Worldwide, Inc. Solvatochromatic bacterial detection
US20060134728A1 (en) * 2003-12-16 2006-06-22 Kimberly-Clark Worlwide, Inc. Microbial detection and quantification
US20060134613A1 (en) * 2004-12-16 2006-06-22 Kimberly-Clark Worldwide, Inc. Detection of microbe contamination on elastomeric articles
US20070140971A1 (en) * 2005-12-15 2007-06-21 Macdonald John G Method for screening for bacterial conjunctivitis
US20080057534A1 (en) * 2006-08-31 2008-03-06 Kimberly-Clark Worldwide, Inc. Microbe-sensitive indicators and use of the same
US20090142275A1 (en) * 2007-11-29 2009-06-04 Kimberly-Clark Worldwide, Inc. Wound Suture Capable of Identifying the Presence of Bacteria

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3969113A (en) * 1971-10-28 1976-07-13 Rank Xerox Ltd. Photosensitive binder layer for xerography containing titanium oxide and a cadmium pigment
US7399608B2 (en) 2003-12-16 2008-07-15 Kimberly-Clark Worldwide, Inc. Microbial detection and quantification
US20060134728A1 (en) * 2003-12-16 2006-06-22 Kimberly-Clark Worlwide, Inc. Microbial detection and quantification
US7282349B2 (en) * 2003-12-16 2007-10-16 Kimberly-Clark Worldwide, Inc. Solvatochromatic bacterial detection
US20070249012A1 (en) * 2003-12-16 2007-10-25 Kimberly-Clark Worldwide, Inc. Microbial Detection and Quantification
US20050130253A1 (en) * 2003-12-16 2005-06-16 Kimberly-Clark Worldwide, Inc. Solvatochromatic bacterial detection
US7687245B2 (en) 2003-12-16 2010-03-30 Kimberly-Clark Worldwide, Inc. Microbial detection and quantification
US8338128B2 (en) 2003-12-16 2012-12-25 Kimberly-Clark Worldwide, Inc. Microbial detection and quantification
US20060134613A1 (en) * 2004-12-16 2006-06-22 Kimberly-Clark Worldwide, Inc. Detection of microbe contamination on elastomeric articles
US7300770B2 (en) 2004-12-16 2007-11-27 Kimberly-Clark Worldwide, Inc. Detection of microbe contamination on elastomeric articles
US20070140971A1 (en) * 2005-12-15 2007-06-21 Macdonald John G Method for screening for bacterial conjunctivitis
US7727513B2 (en) 2005-12-15 2010-06-01 Kimberly-Clark Worldwide, Inc. Method for screening for bacterial conjunctivitis
US20080057534A1 (en) * 2006-08-31 2008-03-06 Kimberly-Clark Worldwide, Inc. Microbe-sensitive indicators and use of the same
US20090142275A1 (en) * 2007-11-29 2009-06-04 Kimberly-Clark Worldwide, Inc. Wound Suture Capable of Identifying the Presence of Bacteria

Also Published As

Publication number Publication date
DE1942383C3 (de) 1975-09-04
CA918984A (en) 1973-01-16
DE1942383B2 (de) 1972-03-16
BE737701A (de) 1970-02-02
FR2016017A1 (de) 1970-04-30
DE1942383A1 (de) 1970-09-10
GB1237036A (en) 1971-06-30
NL6912661A (de) 1970-02-24

Similar Documents

Publication Publication Date Title
US3052540A (en) Dye sensitization of electrophotographic materials
US5529869A (en) Reusable positive-charging organic photoconductor containing phthalocyanine pigment and cross-linking binder
US3705032A (en) Electrophotographic materials
US4547447A (en) Photosensitive members for electrophotography containing phthalocyanine
US3533783A (en) Light adapted photoconductive elements
US2987395A (en) Electrophotographic printing element
JPS5978358A (ja) 熱安定性の赤外線感受性電子写真用組成物
JPS6251462B2 (de)
JPH02271362A (ja) 電子写真像形成部材
US3620729A (en) Electrophotographic coating compositions employing styrene terpolymers as binders
US3447922A (en) Electrically photosensitive particles useful in photoelectrophoretic and xerographic imaging processes
US3152895A (en) Coating composition for the production of electrophotographic recording members
US3155504A (en) Electrophotographic materials
JP3337152B2 (ja) 電子写真感光体の製造方法
US3533787A (en) Photoconductive elements containing polymeric binders of nuclear substituted vinyl haloarylates
US3810759A (en) Matte photoconductive layers for use in electrophotography
US5536611A (en) Dispersing polymers for phthalocyanine pigments used in organic photoconductors
JPS5984247A (ja) 電子写真用感光材料
US3732096A (en) Electrophotographic photosensitive layer
US4283474A (en) Oleophilic resin encapsulates photoconductive zinc oxide particles dispersed in vinyl chloride and vinyl acetate resin binder for electrophotosensitive recording layer
US3554747A (en) Electrostatic printing material and method of its preparation
US3376134A (en) Photoconductive compositions comprising zinc oxide and methods for using such
US3482970A (en) Electrophotographic plate and process using naphthylazo compounds as the primary photoconductor
US3682631A (en) Method of forming an electrophotographic layer containing a benzoguanamine resin binder
US3595650A (en) Photoconductive coating compositions,reproduction materials made therewith,and reproduction processes