CA1127900A - Photoconductive composition containing an organic polymeric photoconductor, an aromatic polycyclic nitro compound and a phthalocyanine - Google Patents
Photoconductive composition containing an organic polymeric photoconductor, an aromatic polycyclic nitro compound and a phthalocyanineInfo
- Publication number
- CA1127900A CA1127900A CA308,088A CA308088A CA1127900A CA 1127900 A CA1127900 A CA 1127900A CA 308088 A CA308088 A CA 308088A CA 1127900 A CA1127900 A CA 1127900A
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- Prior art keywords
- organic polymeric
- phthalocyanine
- photoconductive
- photoconductive composition
- osaka
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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
- G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
- G03G5/0664—Dyes
- G03G5/0696—Phthalocyanines
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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
- G03G5/06—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
- G03G5/072—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds comprising pending monoamine groups
- G03G5/073—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds comprising pending monoamine groups comprising pending carbazole groups
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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
- G03G5/06—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
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- Emergency Medicine (AREA)
- Photoreceptors In Electrophotography (AREA)
- Light Receiving Elements (AREA)
Abstract
S P E C I F I C A T I O N
To ALL WHOM IS MAY CONCERN:
BE IT KNOWN THAT we, Toru Nakazawa, Keiichi Nagahashi and Tatsuo Aizawa, residing at 10-10, 3-Chome, Ikuno Higashi, Ikuno-ku, Osaka-shi, Osaka-fu, Japan, 212-3, Hashimoto, Kaizuka-shi, Osaka-fu, Japan and 6-34, Kuwazu-cho, Higashi-Sumiyoshi-ku, Osaka-shi, Osaka-fu, Japan, respectively, have invented certain new and useful improvements in:
"PHOTOCONDUCTIVE COMPOSITION FOR ELECTROPHOTOGRAPHY ", of which the following is specification.
Abstract of the Disclosure A photoconductive composition suitable for forma-tion of a photosensitive material to be applied to the electrophotographic process in which a photosensitive material is used repeatedly is disclosed. This photoconductive composition comprises an electron-donating organic polymeric conductor, an electron-accepting aromatic polycyclic nitro compound in an amount of 0.15 to 0.45 mole per mole of the constituent monomer of the organic polymeric photoconductor and phthalo-cyanine or its derivative in an amount of 0.2 to 4 %
by weight based on the organic polymeric photoconductor.
A photosensitive material formed by using this photo-conductive composition is characterized by high satura-tion charge voltage, high sensitivity and much reduced residual potential, and it is excellent in mechanical, chemical and electric durabilities and a great number of clear and sharp prints having a high density and being free from fogging can be obtained when this photosensitive material is used repeatedly for the electrophotographic operation.
- 1' -
To ALL WHOM IS MAY CONCERN:
BE IT KNOWN THAT we, Toru Nakazawa, Keiichi Nagahashi and Tatsuo Aizawa, residing at 10-10, 3-Chome, Ikuno Higashi, Ikuno-ku, Osaka-shi, Osaka-fu, Japan, 212-3, Hashimoto, Kaizuka-shi, Osaka-fu, Japan and 6-34, Kuwazu-cho, Higashi-Sumiyoshi-ku, Osaka-shi, Osaka-fu, Japan, respectively, have invented certain new and useful improvements in:
"PHOTOCONDUCTIVE COMPOSITION FOR ELECTROPHOTOGRAPHY ", of which the following is specification.
Abstract of the Disclosure A photoconductive composition suitable for forma-tion of a photosensitive material to be applied to the electrophotographic process in which a photosensitive material is used repeatedly is disclosed. This photoconductive composition comprises an electron-donating organic polymeric conductor, an electron-accepting aromatic polycyclic nitro compound in an amount of 0.15 to 0.45 mole per mole of the constituent monomer of the organic polymeric photoconductor and phthalo-cyanine or its derivative in an amount of 0.2 to 4 %
by weight based on the organic polymeric photoconductor.
A photosensitive material formed by using this photo-conductive composition is characterized by high satura-tion charge voltage, high sensitivity and much reduced residual potential, and it is excellent in mechanical, chemical and electric durabilities and a great number of clear and sharp prints having a high density and being free from fogging can be obtained when this photosensitive material is used repeatedly for the electrophotographic operation.
- 1' -
Description
llZ79~0 Background of the Invention (1) Field of the Invention:
The present invention relates to a photoconductive composition for electrophotography. More specifically, the invention relates to a photoconductive composition which is suitable for the electrophotographic process of the type where the surface of a photoconductive layer is charged and exposed imagewise to actinic radiation to form a charged electrostatic latent image, the so formed latent image is developed with toner particles, the resulting toner image is transferred on a transfer sheet and these photocopying steps are conducted repeatedly.
The present invention provides a photoconductive composition for electrophotography, which comprises an organic polymeric photoconductor having an electron-donating property, an electron-accepting aromatic polycyclic compound having at least one nitro-nuclear substituent, in an amount of 0.15 to 0.45 mole per mole of the constituent monomer of said organic polymeric photoconductor and phthalocyanine or a derivative thereof in an amount of 0.2 to 4% by weight based on said organic polymeric photoconductor,
The present invention relates to a photoconductive composition for electrophotography. More specifically, the invention relates to a photoconductive composition which is suitable for the electrophotographic process of the type where the surface of a photoconductive layer is charged and exposed imagewise to actinic radiation to form a charged electrostatic latent image, the so formed latent image is developed with toner particles, the resulting toner image is transferred on a transfer sheet and these photocopying steps are conducted repeatedly.
The present invention provides a photoconductive composition for electrophotography, which comprises an organic polymeric photoconductor having an electron-donating property, an electron-accepting aromatic polycyclic compound having at least one nitro-nuclear substituent, in an amount of 0.15 to 0.45 mole per mole of the constituent monomer of said organic polymeric photoconductor and phthalocyanine or a derivative thereof in an amount of 0.2 to 4% by weight based on said organic polymeric photoconductor,
(2) Description of the Prior Art:
In the art of electrophotography, there i5 ~roadly adopted ~ process in which a photosensitive material having a photoconductive layer i~ electrically charged ~y corona discharge or the li~e n~eans, the photosensi-tive material is then expDsed imagewise to actinic ~Z7900 radiation to for~n an electrostatic late.nt image on the surface of the phot ~ onductive layer9 a developer is applied to the surface of the photoconductive la-~er to form a toner image corresponding to the electrostatic latent image and the toner image on the surface of the photoconductive layer is transferred to a copy sheet.
In this process9 after transfer of the toner image, the photose.nsitive material. is subjected to the cleaning step for removing the residual toner therefrom9 a.nd the photOsensitive material ~s then fed to the series of the above-me.ntioned steps a~ain.
In order to form an image having high density a.nd contrast, the photoconductive layer of a photosensit-ve material to be used for this eLectrophotogr~phic process is required to haYe the following characteristics in pri.nciple. Namely9 the photoconductive layer ca.n be charged at a sufficiently high potential by the above-mentioned corona discharge ( i.n other words9 the photoco.nductive layer should have a high saturation charge voltage ). Further~ abrupt decrease of the potential is caused when the photoconductive layer is exposed tv actinic radiation after the above charging treatment ( in other words9 the photoconductiVe layer should h~Ve a high Ligh~-decay speed ~f the potential9 i e.9 a high se~sitivity ).
A ph~tosensltlve material to be used repeatedly i,n the above-men~ioned e~ectrophotographio process 7 5 re~uired to have several ohara~te~istios ~hat are not
In the art of electrophotography, there i5 ~roadly adopted ~ process in which a photosensitive material having a photoconductive layer i~ electrically charged ~y corona discharge or the li~e n~eans, the photosensi-tive material is then expDsed imagewise to actinic ~Z7900 radiation to for~n an electrostatic late.nt image on the surface of the phot ~ onductive layer9 a developer is applied to the surface of the photoconductive la-~er to form a toner image corresponding to the electrostatic latent image and the toner image on the surface of the photoconductive layer is transferred to a copy sheet.
In this process9 after transfer of the toner image, the photose.nsitive material. is subjected to the cleaning step for removing the residual toner therefrom9 a.nd the photOsensitive material ~s then fed to the series of the above-me.ntioned steps a~ain.
In order to form an image having high density a.nd contrast, the photoconductive layer of a photosensit-ve material to be used for this eLectrophotogr~phic process is required to haYe the following characteristics in pri.nciple. Namely9 the photoconductive layer ca.n be charged at a sufficiently high potential by the above-mentioned corona discharge ( i.n other words9 the photoco.nductive layer should have a high saturation charge voltage ). Further~ abrupt decrease of the potential is caused when the photoconductive layer is exposed tv actinic radiation after the above charging treatment ( in other words9 the photoconductiVe layer should h~Ve a high Ligh~-decay speed ~f the potential9 i e.9 a high se~sitivity ).
A ph~tosensltlve material to be used repeatedly i,n the above-men~ioned e~ectrophotographio process 7 5 re~uired to have several ohara~te~istios ~hat are not
- 3 -~,.Z79~
required of a photosensitive material of the type where a toner is directly fixed to a photosensitive layer. In order to prevent fogging in repeati.ng the copying operation and prolong the life of the photosensitive material9 the former photosensitive material should have a relatively quick dark decay characteristic ( the property th~t the surface pote,n+ial in the unexposed area of the photosensitive layer ~uickly decays in the dark ) and have such a small residual pote.ntial as can be neglected ( the property that the potential left in the exposed area of the photose.nsitive layer is small ).
When the residllal potential of the photosensitive material s large~ foggi.ng is already caused at the tra,nsfer step, and in this case or whe,n the dark decay speed of the photosensitive materi~l is low9 the static charge of the electrostatic latent image formed on the surface of the photosensitive m~terial is left after the transfer .nd clea.ning step, a.nd the static charge is gradually ~.ccumulated to cause foggi,ng ln the copying operatiOn of the suksequent cycle or cause electric degradatiOn of the photoconductive Layer, Moreover~ whe,n the dark decay speed is low9 eve,n after the tra.nsfer step the toner particles are electrostatically attracted to the sur~ce of the photosensitive material by a relatively 2~ strong attracting force and therefore~ the effiCie~Cy o~` the transfer of the ~oner on a copy sheet is relatively low a.nd a stro.ng wi.pi.ng operati,on should be conducted to remove the residual toner from the surface o~ the ~2 7900 photosensitive material, resulting in a disadva.ntage that the surface of the photosensitive material is readily damaged.
In the photosensitive material of the repeated use type9 it is required. to further improve mechanical, electric a.nd chemical durabilities. Since this photose.nsitive material is subjected to the discharge a.nd irradiation treatment repeatedly and it is caused to have frictional contact with a magnetic brush or cleaning member repeatedly9 the photoconductive layer of the photosensitive material undergoes mechanical damages or is readily electrically or chemically degraded. Further, such troubles as peeling of the photoconductive layer from a conductive substrate are readily caused while the photose.nsitive material is being used.
Various inorganic and organic photoconductors ha~e heretofore bee.n used for formatio.n of photoconductive layers of photosensitive materials. Amor~ these know.n photoconductors9 an organic polymeric photoconductor such as polyvinyl carbazole is characterized by high mechanical9 chemical and electric durabili-ties. Ho~ever~
since a photoconductor of this type has no sensitivity to rays o~ the visible region Accordir~ly~ it ha5 2~ been proposed to use the photoconductor in com~ination .~ith a sensitizer or other photoconductor ~ or example, there has been proposed a method in which a substance acti.ng as a.n electron acceptory such 1~7900 as tri- or tetra-fluorenone ( hereinafter referred to as ~' TNF ~ ) 9 iS incorporated into an electron-donati.ng organic polymeric photoconductor such as polyvi.nyl carbazole ( hereinafter refel~red to as " PVK " ) and the organic polymeric photoconductor is sensitized by thus conYerti.ng it to a charge-tra.nsfer complex ( see USP ~4~9237 ~. This photoconductive composi.tion is advantageous i.n that it is excellent in the abo~e-mentioned photo-electric characteristics, However, in order to attain the intended effect. expensive TNF
should be incorporated in such a large amount as 0~49 to 1.23 moles per mole of the constituent monomer of PVK9 and therefore9 a defect that the cost of a photo-sensitive plate is increased Ca.nnOt be avoided. When the amount used of TNF is reduced below 0.49 mole per mole of the constituent monomer so as to lower the manufacturing cost of a photosensitive plate9 the sensitivlty is decreased to such a low level as not practically applicable.
Japanese Patent Application Laid-Ope.n Specification No. 18545/72 proposes a photoconductive composition com~rising PVK and phthalocyanine or its derivative ( hereinafter re~erred to as " Pc " ~. This PVK-Pc composition has a relatively good sensitivity to a positi~e cha~ge9 but this composi~ion does not show a sensitivity to a negative charge to such an extent that a photosensiti~e material fo~med ~y using this compo-sition can be used ~or ordinary commercial e~ectrophoto-liZ7900 graphic copying machines. Especially in a photosensitive plate formed by using this composition9 the residual potential a ter the transfer is at such a high level as cannot be neglected, a.nd fogging is caused while the copying operation is repeated or the life of the photo-sensitive material is drastically shortened.
In Example 2 of USP 3,8163118~ it is disclosed that a composition formed by incorporating i.n polyvinyl carbazole a relatively small amount of 2~4,7-tri.nitro-9-fluore:ne and a relatively large amount of phthalocyanineis used for formation of a photoconductive layer, the red se.nsitivity is increased. However, as illustrated in Comparative ~xample ~ given hereinafter7 this known PVK-TNF-Pc composition has a low initial pote.ntial and 15 a low se.nsitivity9 and it has not electrophotographiC
characteristics sufficient for the resulting photosensi-tive material to be applicable to the copying OperatiOn usi.ng a commercial electrophotographic copyi:ng machi.ne Further9 this known composition is poor in adherence 20 to a co.nductive substrate and the durability of the resulting photoconductive layer is insufficient.
Brie~ Sun~.ar~; of the Invention We foun~ that a photoconductive cornposition forme~
by inco~porating specific amounts of a.n electron-accepting ~ror~atic polycyclic nitro cornpound such as TNF and phthalocy~..nine or its ~eriYative lnto ~n electron-dvnating organic polymeric photocon~uctor such as P~K
has a high saturatio.n cha~ge voltage and a quick light ~79w decay spee~ ( a ~ligh sensitivity ) i.n combinaticn~ a.nd that in a photosensitive material formed by using this composition9 the dark decay A~peed can be controlled within a ra.nge suitable for repeated copying and the residual potenti~l can be reduced to such a level as can be .neglected9 whereby occurrence of foggi.ng can ~e prevented9 the toner transfer ef~iciency can be improved a.nd the llfe of the photosensitive material can be remarkabl~, ~rolo.nged. It also was fou.nd th~t thè
above-mentio.ned photoconducti~e compositio.n is promi-ne.ntly excellent i.n the mechanical~ chemical a.nd electric durabi.lities. Based on these fi.ndings, we have .now completed the present in~ention.
More specifically, in accorda.nce with the present irlve:ntio.n~ there is provided a photoconductive composi-tion for electrophotography9 which comprises an organic pol.ymeric photoconductor having an donating activity, an electron-accepting aromatic polycyclic nitrO com-pou.nd in an amount of 0.15 to 0.4~ mole per mole of the constituent monomer of said Grganic polymeric photo-conductor and phtha~locyanine or its derivative in an amount of 0.2 to 4 /0 by weight ba.sed on said orga.nic polyrneric photoconductor.
Brief ~escript ~
Fig. 1 is a diagrarn illustrati.ng t;he saturation charge vol~,age ( ~s ).
Fig . 2 is a Aiagram illustrating the initia7 potential ~ VI ~ an~ the residual potential ( V~ ).
'1~0 Fig. 3 is a curve showi.ng electric a.nd photoco.nduc-tive characteristics of photoconductive compositions of the present invention and comparative photoconductive compositions.
Detai.led Description of the Pre~rrea ~rbw~;meAt Electrostatic a.nd photo-electric characteristic referred to i.n ~he instant specification will .ncw be descri~ed by reference to Figs. 1 and 2.
Saturatio.n Charge Voltage:
An electrostatic paper à.nalyzer ( ma.nufactured by Kaw~guchi Denki ) is used under the dy.namic measurement conditio.ns9 and coro.na discharge of - 5 KY or + 5 KV is applied to a photocondu¢tive layer for 10 seco.nds and the saturation voltage on the surface of the photocon-ductive layer is determi.ned ( Vs in Fig~ 1 ). This saturation voltage mea.ns the saturatio.n charge voltage of the photoconductive layer.
Dark Decay:
Under the same conditions as me.ntioned above, the corona discharge is co.nducted. When 10 seconds have passed at the poi.nt of terminatiOn of the coro.na dis-charge9 the average decay DD f the surface potential of the photoco.nducti~e layer is calculated accordi.ng to the followi.ng formula:
2~
wherei.n Vs stands ~or the saturation charge Yoltage ~lZ79QO
defined above a.nd V10 sta.nds for the surface pcten-tial of the photoconductive layer measured when 10 seconds have passed from the point of termi.nation of the corona discharge.
The dark decay means this average decay DD.
Initial Pote.ntial:
The above-mentioned electrostatic paper a.nalyzer is used under static measurement conditions a.nd a photocoductive layer is subjected to corona discharge of - 5 KV or + 5 KV. The initial pote.ntial means the surface pote.ntial of the photoco.nductive layer measured JUSt before irradiation ( VI in ~ig. 2 ).
Residual Pote.ntial:
The residual pote.ntial means a surface pote.ntial f a photoconductive layer subjected to the above-mentioned corona discharge ? which is measured at a point when irradiation has been conducted at 40 luxes for 1 second ( ~R in ~ig- 2 )-Sensitivity:
The sensitivity means a relati~e ~alue of the quan-tity of exposure necessary for the surface potential of t;he photoconductive layer to be reduced to 1/2 of the initial potential ( VI )g namely the half-deca.y exposure qua.ntity represented by the fcllowi~g formula:
S - t X T~
wherein ~; st~nds Ior the h~lf-decay exposure ~ua.ntity~ i,e,, the sensitivlty, t stands ~or a time ( second 3 necessary for the surface potential 1~79QO
to be reduced to 1/2 of the i.nitial pote.ntial VI
after i.nitiation of irradiation9 and L sta.nds for a.n average illumina.nce t lux ) of irradiation.
A smaller value indicates a higher sensitivity.
The photoconductive composition of the prese.nt i.nvention comprises a.n electron-donating orga.nic poly-meric photoconductor~ an electron-accepting aromatic polycyclic .nitro compound and phthalocyanine or its derivative at a specific ratio, and the present inve.ntion is based on the findi.ng that this photoconduc-tive compositio.n is promine.ntly e~sellent over co.nven-tio.nal photoconductive compositions lacki.ng a.ny of the foregoing three components in the above-mentioned electrostatic and photo-electric characteristics. More illustratively7 a photoconductive composition of the two compone.nt type comprisi.ng a.n electron-donati.ng organic polymeric photoconductor and an electron-accepti.ng aromatic polycyclic .nitro compound at a ratio falling i.n the mixing ratio specified i.n the prese.nt invention 2C ( see the specifications of U. S. Pate.nts No. 3,159,483 a.nd No. 3~232~755 ) is defective in that the sensitivity to light is low a.nd the residual potential a~ter exposure is high~ as sh~w.n in Comparative Example 1 gi~en hereina~ter. There~ore~ a photoconductive composition f this type can hardly be used for electrophotography of the type where the photoconduotive layer is used repeatedly after the copying operation. Further, a photoconductive composition comprising a.n electron-~o ~
donating organic polymeric photoco.nductor and phthalocyanine or its derivati~e at a ratio falling within the mixing ratio speclfied i.n the present i.nve.n-tion ( see Japanese Pate.nt Application Laid-Open Specification No. 18545/72 ) is defective in that the sensitivity to light is low a.nd the residual potential after exposure is high, as shown i.n Comparative Example 2 given hereinafter. Therefore, a photoconduc-tive compositio.n of this type can hardly be used for ~lectrophotography of the type where the photoconductive layer is used repeatedly. ~urther, a photoconduc+ive composi'ion of the two compone.nt type comprising phthalocya.ninè or its derivative and an electron-do.nating aromatic polycyclic nitro compou.nd such as T~F
1~ ( see USP 3,~949868 ) is defective in that the formed photoconductive layer is extremely poor i.n the mechanical, chèmical a.nd electric durabilities9 the saturation charge voltage is very l.ow and an image havi.ng a high de.nsity ca.n. hardl.y be Gbtai.ned, as shown in Comparative ~xample 3 given hereinafter. Therefore, a photoconduc-tive composition of this type can hardly be applied to electrophotography o~ the type where the photoconducti~e layer is used repeatedly.
In contrast, when an electron-donating organic polymeric p~otoconductor~ an electron-accepting aromatic polycyclic .nitro compoun~ a.nd phthalocyanine or its derivative are combined l.n spec3.fic amou.nts according to the present in~ention~ ~ecause of the synergistic li2790~
actions of these components9 both the saturation charge voltage a.nd the sensitivity to light can be remarkably elevated9 the residual pote.ntial after exposure can be reduced tG zero or such a low level as ca.n be neglected and the mecha.nical9 chemical a.nd electric durabilities of the photoco.nductive layer can be remarka~ly improved.
Therefore9 when the composition of the present i.nvention is used for formation of a photoconductive layer, in electrophotography of the type where the photoconductive layer is used repeatedly9 it becomes possible to i.ncrease the toner tra.nsfer ef.ficiency a:nd obtai.n a clear copied image while preventing occurrence of fogging and a gre~t number of prints can be obtai.ned from one photoconduc-tive layer. Further, accordi.ng to the prese.nt inve.ntion, there can be attained a prominent advanta~e that the excellent effects of improvi.ng the saturatio.n charge voltage and the sensitivity and reduci.ng the residual pote.ntial after exposure can be obtained by using much smaller amou.nts of the above-mentioned nitro compound and phthalocyanine or its derivative than in the ConYen-tio.nal known photoconductive compositions9 because of the synergistic actions of the two components.
ln the photoconductive compGsition of the present inve.ntion~ phthalocyanine or its derivative is unlformly dispersed in a cOntinuous ph~se of the org~nic polymeric photoconductor and this disperse phase is ~ery ~ine, and it is believed that the conti.nuous phase of the electron-donating organic pol~meric photoconductor forms l~ 00 a charge-transfer complex with the electron-accepti.r~
aromatic polycyclic nitro compound. A system comprising phthalocyanine or its deri~ative dispersed i.n a conti-.nuous phase of the orga.nic polymeric photoco.nductor shows a relatively good sensitivity to light whenpOSitiVe charges are applied9 but whe.n this system is .negatively charged a.nd then exposed to actinic radiation, no practically satisfactory sensitivity is obtained.
In co.ntrast, when the organic polymeric photoconductor of the co.nti.nuous phase is co.nverted to a complex with the electron~accepti.ng aromatic polycyclic nitro com-pound accordi.ng to the present i.nve.ntion, also when the photoco.nductive layer is negatively charged9 a very excelle.nt se.nsitivity is obtained and this sensitizing effect can be attained by usi.r~ the aromatic polycyclic nitro compound in an amount much smaller than the minimum amount .necessary for sensitizi.ng the organic polymeric photoconductor to charges of the negative polarity by the aromatic polycyclic nitro compound alone. This is ~uite a surprisi.ng fi.nding.
Any of known po]ymeric substances havir~ electro.n-donating and photoconductive properties can be u~ed as the organic polymeric photoconductor in the present i.nvention. For example, there can be used poly-N-vinylcarbazole~ poly-N-acrylphenothiazi.ne~ poly-N-(~-acryloxyethy])-phenothiazine, poly-N-~2-acryloxypropyl)-phenothiazine9 poly-N-allylcarbazole, poly-N-2-acryloxy-2-methyl-N-ethylcarbazole9 poly-N-(2-p-vinylbenzoylethyl)-carbazole9 poly-N-propenylcarbazole9 poly-N-2-methylacryl-oxapropylcarbazole, poly-N-acrylcarbazole9 poly-4-vi.nyl-p-(N-carbazyl)-toluene, poly(vi.nylanizalacetophenone39 polyinde.ne and other known photoco.nductive polymers.
Polymeric photOconductors that are easily available a.nd suitable for attaini.ng the objects of the present invention are poly-N-vi.nylcarbazole and nuclear substi-tution products such as haloge.n- and alkyl-substituted derivatives thereof, Any of known aromatic polycyclic compounds havi.ng at least one nitro group as the nuclear substituent a.nd having an electro.n-accepti.ng property can be used as the electron-accepting aromatic polycyclic nitro com-pound. For example9 there can be used 294-di.nitro-l-chloronaphthalene, 1,4-dinitro.naphthalene, 1,5-di.nitronaphthalene9 3-nitro-N-butyl-carbazole, 4-nitro-biphe:nyl7 4,4'-di.nitrobiphenyl9 1-chloro-4-nitroanthra-quinone) 2,7-dinitroanthraquinone9 294,7-trinitrofluore-none, 2~49 59 7-tetranitrofluorenone? 9-dicyanomethyle.ne-29497-trinitrofluore.none and 4-nitroacenaphthe.ne Trinitro- a.nd tetranitro-fluorenones are especially suitable for attaining the objects of the present inven-tion.
Any of know.n phthalocyanine a.nd phthalocyanine derivatives having a photoconductive property can be used as phthalocyanine or its derivative. Suitable examples are aluminum phthalocyani.ne9 alumi.num poly-chlorophthalocyanine9 antimony phthalccyani.ne, barium phthalocya.nine9 beryllium phthalocyani.ne, cadmium hexadecachlorophthalocyanine7 cadmium phthalocyanine, cerium phthalocyanine9 chromium phthalocyani.ne9 cobalt phthalocya.ni.ne9 cobalt chlorophthalocyanine9 copper
required of a photosensitive material of the type where a toner is directly fixed to a photosensitive layer. In order to prevent fogging in repeati.ng the copying operation and prolong the life of the photosensitive material9 the former photosensitive material should have a relatively quick dark decay characteristic ( the property th~t the surface pote,n+ial in the unexposed area of the photosensitive layer ~uickly decays in the dark ) and have such a small residual pote.ntial as can be neglected ( the property that the potential left in the exposed area of the photose.nsitive layer is small ).
When the residllal potential of the photosensitive material s large~ foggi.ng is already caused at the tra,nsfer step, and in this case or whe,n the dark decay speed of the photosensitive materi~l is low9 the static charge of the electrostatic latent image formed on the surface of the photosensitive m~terial is left after the transfer .nd clea.ning step, a.nd the static charge is gradually ~.ccumulated to cause foggi,ng ln the copying operatiOn of the suksequent cycle or cause electric degradatiOn of the photoconductive Layer, Moreover~ whe,n the dark decay speed is low9 eve,n after the tra.nsfer step the toner particles are electrostatically attracted to the sur~ce of the photosensitive material by a relatively 2~ strong attracting force and therefore~ the effiCie~Cy o~` the transfer of the ~oner on a copy sheet is relatively low a.nd a stro.ng wi.pi.ng operati,on should be conducted to remove the residual toner from the surface o~ the ~2 7900 photosensitive material, resulting in a disadva.ntage that the surface of the photosensitive material is readily damaged.
In the photosensitive material of the repeated use type9 it is required. to further improve mechanical, electric a.nd chemical durabilities. Since this photose.nsitive material is subjected to the discharge a.nd irradiation treatment repeatedly and it is caused to have frictional contact with a magnetic brush or cleaning member repeatedly9 the photoconductive layer of the photosensitive material undergoes mechanical damages or is readily electrically or chemically degraded. Further, such troubles as peeling of the photoconductive layer from a conductive substrate are readily caused while the photose.nsitive material is being used.
Various inorganic and organic photoconductors ha~e heretofore bee.n used for formatio.n of photoconductive layers of photosensitive materials. Amor~ these know.n photoconductors9 an organic polymeric photoconductor such as polyvinyl carbazole is characterized by high mechanical9 chemical and electric durabili-ties. Ho~ever~
since a photoconductor of this type has no sensitivity to rays o~ the visible region Accordir~ly~ it ha5 2~ been proposed to use the photoconductor in com~ination .~ith a sensitizer or other photoconductor ~ or example, there has been proposed a method in which a substance acti.ng as a.n electron acceptory such 1~7900 as tri- or tetra-fluorenone ( hereinafter referred to as ~' TNF ~ ) 9 iS incorporated into an electron-donati.ng organic polymeric photoconductor such as polyvi.nyl carbazole ( hereinafter refel~red to as " PVK " ) and the organic polymeric photoconductor is sensitized by thus conYerti.ng it to a charge-tra.nsfer complex ( see USP ~4~9237 ~. This photoconductive composi.tion is advantageous i.n that it is excellent in the abo~e-mentioned photo-electric characteristics, However, in order to attain the intended effect. expensive TNF
should be incorporated in such a large amount as 0~49 to 1.23 moles per mole of the constituent monomer of PVK9 and therefore9 a defect that the cost of a photo-sensitive plate is increased Ca.nnOt be avoided. When the amount used of TNF is reduced below 0.49 mole per mole of the constituent monomer so as to lower the manufacturing cost of a photosensitive plate9 the sensitivlty is decreased to such a low level as not practically applicable.
Japanese Patent Application Laid-Ope.n Specification No. 18545/72 proposes a photoconductive composition com~rising PVK and phthalocyanine or its derivative ( hereinafter re~erred to as " Pc " ~. This PVK-Pc composition has a relatively good sensitivity to a positi~e cha~ge9 but this composi~ion does not show a sensitivity to a negative charge to such an extent that a photosensiti~e material fo~med ~y using this compo-sition can be used ~or ordinary commercial e~ectrophoto-liZ7900 graphic copying machines. Especially in a photosensitive plate formed by using this composition9 the residual potential a ter the transfer is at such a high level as cannot be neglected, a.nd fogging is caused while the copying operation is repeated or the life of the photo-sensitive material is drastically shortened.
In Example 2 of USP 3,8163118~ it is disclosed that a composition formed by incorporating i.n polyvinyl carbazole a relatively small amount of 2~4,7-tri.nitro-9-fluore:ne and a relatively large amount of phthalocyanineis used for formation of a photoconductive layer, the red se.nsitivity is increased. However, as illustrated in Comparative ~xample ~ given hereinafter7 this known PVK-TNF-Pc composition has a low initial pote.ntial and 15 a low se.nsitivity9 and it has not electrophotographiC
characteristics sufficient for the resulting photosensi-tive material to be applicable to the copying OperatiOn usi.ng a commercial electrophotographic copyi:ng machi.ne Further9 this known composition is poor in adherence 20 to a co.nductive substrate and the durability of the resulting photoconductive layer is insufficient.
Brie~ Sun~.ar~; of the Invention We foun~ that a photoconductive cornposition forme~
by inco~porating specific amounts of a.n electron-accepting ~ror~atic polycyclic nitro cornpound such as TNF and phthalocy~..nine or its ~eriYative lnto ~n electron-dvnating organic polymeric photocon~uctor such as P~K
has a high saturatio.n cha~ge voltage and a quick light ~79w decay spee~ ( a ~ligh sensitivity ) i.n combinaticn~ a.nd that in a photosensitive material formed by using this composition9 the dark decay A~peed can be controlled within a ra.nge suitable for repeated copying and the residual potenti~l can be reduced to such a level as can be .neglected9 whereby occurrence of foggi.ng can ~e prevented9 the toner transfer ef~iciency can be improved a.nd the llfe of the photosensitive material can be remarkabl~, ~rolo.nged. It also was fou.nd th~t thè
above-mentio.ned photoconducti~e compositio.n is promi-ne.ntly excellent i.n the mechanical~ chemical a.nd electric durabi.lities. Based on these fi.ndings, we have .now completed the present in~ention.
More specifically, in accorda.nce with the present irlve:ntio.n~ there is provided a photoconductive composi-tion for electrophotography9 which comprises an organic pol.ymeric photoconductor having an donating activity, an electron-accepting aromatic polycyclic nitrO com-pou.nd in an amount of 0.15 to 0.4~ mole per mole of the constituent monomer of said Grganic polymeric photo-conductor and phtha~locyanine or its derivative in an amount of 0.2 to 4 /0 by weight ba.sed on said orga.nic polyrneric photoconductor.
Brief ~escript ~
Fig. 1 is a diagrarn illustrati.ng t;he saturation charge vol~,age ( ~s ).
Fig . 2 is a Aiagram illustrating the initia7 potential ~ VI ~ an~ the residual potential ( V~ ).
'1~0 Fig. 3 is a curve showi.ng electric a.nd photoco.nduc-tive characteristics of photoconductive compositions of the present invention and comparative photoconductive compositions.
Detai.led Description of the Pre~rrea ~rbw~;meAt Electrostatic a.nd photo-electric characteristic referred to i.n ~he instant specification will .ncw be descri~ed by reference to Figs. 1 and 2.
Saturatio.n Charge Voltage:
An electrostatic paper à.nalyzer ( ma.nufactured by Kaw~guchi Denki ) is used under the dy.namic measurement conditio.ns9 and coro.na discharge of - 5 KY or + 5 KV is applied to a photocondu¢tive layer for 10 seco.nds and the saturation voltage on the surface of the photocon-ductive layer is determi.ned ( Vs in Fig~ 1 ). This saturation voltage mea.ns the saturatio.n charge voltage of the photoconductive layer.
Dark Decay:
Under the same conditions as me.ntioned above, the corona discharge is co.nducted. When 10 seconds have passed at the poi.nt of terminatiOn of the coro.na dis-charge9 the average decay DD f the surface potential of the photoco.nducti~e layer is calculated accordi.ng to the followi.ng formula:
2~
wherei.n Vs stands ~or the saturation charge Yoltage ~lZ79QO
defined above a.nd V10 sta.nds for the surface pcten-tial of the photoconductive layer measured when 10 seconds have passed from the point of termi.nation of the corona discharge.
The dark decay means this average decay DD.
Initial Pote.ntial:
The above-mentioned electrostatic paper a.nalyzer is used under static measurement conditions a.nd a photocoductive layer is subjected to corona discharge of - 5 KV or + 5 KV. The initial pote.ntial means the surface pote.ntial of the photoco.nductive layer measured JUSt before irradiation ( VI in ~ig. 2 ).
Residual Pote.ntial:
The residual pote.ntial means a surface pote.ntial f a photoconductive layer subjected to the above-mentioned corona discharge ? which is measured at a point when irradiation has been conducted at 40 luxes for 1 second ( ~R in ~ig- 2 )-Sensitivity:
The sensitivity means a relati~e ~alue of the quan-tity of exposure necessary for the surface potential of t;he photoconductive layer to be reduced to 1/2 of the initial potential ( VI )g namely the half-deca.y exposure qua.ntity represented by the fcllowi~g formula:
S - t X T~
wherein ~; st~nds Ior the h~lf-decay exposure ~ua.ntity~ i,e,, the sensitivlty, t stands ~or a time ( second 3 necessary for the surface potential 1~79QO
to be reduced to 1/2 of the i.nitial pote.ntial VI
after i.nitiation of irradiation9 and L sta.nds for a.n average illumina.nce t lux ) of irradiation.
A smaller value indicates a higher sensitivity.
The photoconductive composition of the prese.nt i.nvention comprises a.n electron-donating orga.nic poly-meric photoconductor~ an electron-accepting aromatic polycyclic .nitro compound and phthalocyanine or its derivative at a specific ratio, and the present inve.ntion is based on the findi.ng that this photoconduc-tive compositio.n is promine.ntly e~sellent over co.nven-tio.nal photoconductive compositions lacki.ng a.ny of the foregoing three components in the above-mentioned electrostatic and photo-electric characteristics. More illustratively7 a photoconductive composition of the two compone.nt type comprisi.ng a.n electron-donati.ng organic polymeric photoconductor and an electron-accepti.ng aromatic polycyclic .nitro compound at a ratio falling i.n the mixing ratio specified i.n the prese.nt invention 2C ( see the specifications of U. S. Pate.nts No. 3,159,483 a.nd No. 3~232~755 ) is defective in that the sensitivity to light is low a.nd the residual potential a~ter exposure is high~ as sh~w.n in Comparative Example 1 gi~en hereina~ter. There~ore~ a photoconductive composition f this type can hardly be used for electrophotography of the type where the photoconduotive layer is used repeatedly after the copying operation. Further, a photoconductive composition comprising a.n electron-~o ~
donating organic polymeric photoco.nductor and phthalocyanine or its derivati~e at a ratio falling within the mixing ratio speclfied i.n the present i.nve.n-tion ( see Japanese Pate.nt Application Laid-Open Specification No. 18545/72 ) is defective in that the sensitivity to light is low a.nd the residual potential after exposure is high, as shown i.n Comparative Example 2 given hereinafter. Therefore, a photoconduc-tive compositio.n of this type can hardly be used for ~lectrophotography of the type where the photoconductive layer is used repeatedly. ~urther, a photoconduc+ive composi'ion of the two compone.nt type comprising phthalocya.ninè or its derivative and an electron-do.nating aromatic polycyclic nitro compou.nd such as T~F
1~ ( see USP 3,~949868 ) is defective in that the formed photoconductive layer is extremely poor i.n the mechanical, chèmical a.nd electric durabilities9 the saturation charge voltage is very l.ow and an image havi.ng a high de.nsity ca.n. hardl.y be Gbtai.ned, as shown in Comparative ~xample 3 given hereinafter. Therefore, a photoconduc-tive composition of this type can hardly be applied to electrophotography o~ the type where the photoconducti~e layer is used repeatedly.
In contrast, when an electron-donating organic polymeric p~otoconductor~ an electron-accepting aromatic polycyclic .nitro compoun~ a.nd phthalocyanine or its derivative are combined l.n spec3.fic amou.nts according to the present in~ention~ ~ecause of the synergistic li2790~
actions of these components9 both the saturation charge voltage a.nd the sensitivity to light can be remarkably elevated9 the residual pote.ntial after exposure can be reduced tG zero or such a low level as ca.n be neglected and the mecha.nical9 chemical a.nd electric durabilities of the photoco.nductive layer can be remarka~ly improved.
Therefore9 when the composition of the present i.nvention is used for formation of a photoconductive layer, in electrophotography of the type where the photoconductive layer is used repeatedly9 it becomes possible to i.ncrease the toner tra.nsfer ef.ficiency a:nd obtai.n a clear copied image while preventing occurrence of fogging and a gre~t number of prints can be obtai.ned from one photoconduc-tive layer. Further, accordi.ng to the prese.nt inve.ntion, there can be attained a prominent advanta~e that the excellent effects of improvi.ng the saturatio.n charge voltage and the sensitivity and reduci.ng the residual pote.ntial after exposure can be obtained by using much smaller amou.nts of the above-mentioned nitro compound and phthalocyanine or its derivative than in the ConYen-tio.nal known photoconductive compositions9 because of the synergistic actions of the two components.
ln the photoconductive compGsition of the present inve.ntion~ phthalocyanine or its derivative is unlformly dispersed in a cOntinuous ph~se of the org~nic polymeric photoconductor and this disperse phase is ~ery ~ine, and it is believed that the conti.nuous phase of the electron-donating organic pol~meric photoconductor forms l~ 00 a charge-transfer complex with the electron-accepti.r~
aromatic polycyclic nitro compound. A system comprising phthalocyanine or its deri~ative dispersed i.n a conti-.nuous phase of the orga.nic polymeric photoco.nductor shows a relatively good sensitivity to light whenpOSitiVe charges are applied9 but whe.n this system is .negatively charged a.nd then exposed to actinic radiation, no practically satisfactory sensitivity is obtained.
In co.ntrast, when the organic polymeric photoconductor of the co.nti.nuous phase is co.nverted to a complex with the electron~accepti.ng aromatic polycyclic nitro com-pound accordi.ng to the present i.nve.ntion, also when the photoco.nductive layer is negatively charged9 a very excelle.nt se.nsitivity is obtained and this sensitizing effect can be attained by usi.r~ the aromatic polycyclic nitro compound in an amount much smaller than the minimum amount .necessary for sensitizi.ng the organic polymeric photoconductor to charges of the negative polarity by the aromatic polycyclic nitro compound alone. This is ~uite a surprisi.ng fi.nding.
Any of known po]ymeric substances havir~ electro.n-donating and photoconductive properties can be u~ed as the organic polymeric photoconductor in the present i.nvention. For example, there can be used poly-N-vinylcarbazole~ poly-N-acrylphenothiazi.ne~ poly-N-(~-acryloxyethy])-phenothiazine, poly-N-~2-acryloxypropyl)-phenothiazine9 poly-N-allylcarbazole, poly-N-2-acryloxy-2-methyl-N-ethylcarbazole9 poly-N-(2-p-vinylbenzoylethyl)-carbazole9 poly-N-propenylcarbazole9 poly-N-2-methylacryl-oxapropylcarbazole, poly-N-acrylcarbazole9 poly-4-vi.nyl-p-(N-carbazyl)-toluene, poly(vi.nylanizalacetophenone39 polyinde.ne and other known photoco.nductive polymers.
Polymeric photOconductors that are easily available a.nd suitable for attaini.ng the objects of the present invention are poly-N-vi.nylcarbazole and nuclear substi-tution products such as haloge.n- and alkyl-substituted derivatives thereof, Any of known aromatic polycyclic compounds havi.ng at least one nitro group as the nuclear substituent a.nd having an electro.n-accepti.ng property can be used as the electron-accepting aromatic polycyclic nitro com-pound. For example9 there can be used 294-di.nitro-l-chloronaphthalene, 1,4-dinitro.naphthalene, 1,5-di.nitronaphthalene9 3-nitro-N-butyl-carbazole, 4-nitro-biphe:nyl7 4,4'-di.nitrobiphenyl9 1-chloro-4-nitroanthra-quinone) 2,7-dinitroanthraquinone9 294,7-trinitrofluore-none, 2~49 59 7-tetranitrofluorenone? 9-dicyanomethyle.ne-29497-trinitrofluore.none and 4-nitroacenaphthe.ne Trinitro- a.nd tetranitro-fluorenones are especially suitable for attaining the objects of the present inven-tion.
Any of know.n phthalocyanine a.nd phthalocyanine derivatives having a photoconductive property can be used as phthalocyanine or its derivative. Suitable examples are aluminum phthalocyani.ne9 alumi.num poly-chlorophthalocyanine9 antimony phthalccyani.ne, barium phthalocya.nine9 beryllium phthalocyani.ne, cadmium hexadecachlorophthalocyanine7 cadmium phthalocyanine, cerium phthalocyanine9 chromium phthalocyani.ne9 cobalt phthalocya.ni.ne9 cobalt chlorophthalocyanine9 copper
4-ami.nophthalocyanine, copper bromochlorophthalocyanine, copper 4-chlorophthalocyanine9 copper phthalocya.nine sulfonate9 copper polychlorophthalocyanine9 dysprosium phthalocyanine9 erbium phthalocyanine, europium phthalo-cyani.ne9 gadolinium phthalocya.ni.ne, ~allium phthalocya-nine9 germa.nium phthalocyanine, holmium phthalocya.ni.ne,indium ph~halocya.nine9 iron phthalocyanine9 iron polyhalophthalocyanine9 la.nthanum phthalocyanine9 lead phthalocyani.ne9 lead polychlorophthalocyanine9 cobalt hex2phe.nylphthalocyanine9 copper pentaphenylphthalocya.nine, lithium phthalocyani.ne9 lutetium phthalocyanine9 magnesium phthalocya.ni.ne7 ma.nganese phthalocyanine, mercury phthalocyanine9 molybde.num phthalocyanine, neodium phth~locyanine9 nickel phthalocyani.ne, nickel-polyhalophthalocy~nine7 osmium phthalocyanine9 palladium phth~locyanine9 palladium chlorophthalocyani.ne9 alkoxyphthalocyanine9 alkylaminophthalocyanine9 alkylmercPptophthalocyani.ne9 arylmercaptophthalocyanine, copper phthalocya.nine-piperidine9 cycloalkylami.nophthalo-cyanine, dialkylaminophthalocyanine, diaralkylami.noph-thalocyani.ne9 dicycloalkylaminophthalocya.nine9 hexade-cahydrophthalocyanine9 imidomethylphthalocyanine, octa-azophthalocyanine7 sulfur phthalocyanine, tetra-azophtha-locyanine7 tetra-4-aminobenzoylphthalocyanine9 tetra-4-acetylaminophthalocyanine, tetra-4-aminophthalocyanine, tetrachloromethylphthalocyanine, tetradiazophthalocya-nine9 tetra-494-dimethylocta-azophthalocyanine9 tetra-495-diphenylene-dioxide-phthalocyani.ne9 tetra-49 ~
diphe:nylocta-azophthalocya.nine9 tetra-(6-methyl-be.nzo-thiazoyl)phthalocya.nine9 tetra-p-methylphenylaminoph-thalocyani.ne9 tetramethylphthalocyanine9 tetra-4-naphthotriazolphthalocyanine9 tetra-4-naphthylphtha-locyanine9 tetra-L.-.nitrophthalocyani.ne9 tetraperinaph-thylene-4,5-octa-azophthalocyani.ne9 tetra-2,3-phe.nylene-oxide-phthalocyanine9 tetra-4-phenylocta-azophthalocya.ni.ne9 tetraphenylphthalocyanine9 tetra-phe.nylphthalocyani.ne-tetracarboxylic acid, tetraphenyl-phthalocyan:ine tetrabarium carboxylate9 tetra-4-trifluro-methylmercaptophth~locya.nine9 tetrapyridylphthalocyanine, tetra-4-trifluoromethylmercaptophthalocyanine, tetra-4-trifluoromethylphth~locyanine-4,5-thio.n2phthene-octa-azophthalocyanine, platinum phthalocyanine9 potassium phthalocya.nine9 thodium phthalocyanine9 samarium phthalo-cyanine, silver phthalocyanine9 silicon phthalocyanine,sodium phthalocyanine9 sulfonated phthalocyanine, thorium phthalocya.ni.ne9 thulium phthalocyanine9 tin chlorophthalocyanine9 tin phthalocyanine, titanium phthalocya.ni.ne9 uranium phthalocyanine9 vanadium phtha-locya.nine9 zi.nc chlorophthalocyanine9 zinc phthalocyanine,and dimers9 trimers9 oligomers9 homopolymers and copolymers thereof Metal-free phthalocya.nines and nuclear substitution products thereof9 for example, haloge.n .nuclear substitution products thereof, are easily available and especially suitable for attaining the objects of the present invention.
I.n the prese.nt inve.ntion9 it is very important that the electron-accepti.ng aromatic polycyclic .nitro compound should be used in an amou.nt of 0.15 to 0.45 mole per mole of the constituent monomer of the electro.n-do.nati.ng organic polymeric photoco.nductor and that pm halocyanine or its derivative should be used in an amount of 0.2 to 4 % by weight based on the organic polymeric photoconduc-tor.
Whe.n the amount of the phthalocyanine is below the above range9 the sensitivity to light is reduced and the residual pote.ntial after exposure is readily i.ncreased.
When the amou.nt of the phthalocya.nine exceeds the above range9 the saturation charge voltage is lowered a.nd also the sensitivity to light is reduced. Further9 a composi-tio.n comprisi.ng the phthalocya.ni.ne i.n too large an amount is poor i.n th@ coating-forming property a.nd i.n this composition9 there is observed a te.nde.ncy that the mechanical strength or ~dhesion of the coating is insufficient.
When the amou.nt of the aromatic polycyclic nitro compound is below the above range9 the sensitivity to light is reduced and increase of the residual potential after exposure is conspicuous. When the amount of the aromatic polycyclic nitro compound exceeds the above range9 the saturation charge voltage is drastically ~Z7XIV
reduced.
As will be apparent from the foregoing, whe.n TNF
or Pc is incorporated i.nto an organic polymeric photo-conductor9 if the amount i.ncorporated is small, the se.nsitivity is low a.nd the residual pote.ntial is increased. On the other hand9 if the amount i.ncorpora ted is increasedg the saturation charge voltage te.nds to decrease~
I.n co.ntrast9 if both the aromatic polycyclic nitro compound a.nd phthalocyani.ne or its derivative are incorporated in combi.nation in specific small amounts accordi.ng to the present i.nvention, it is made possible to satisfy two co.ntradictory requirements, namely increase of the saturation charge voltage a.nd reduction of the residual pote.ntial.
I.n additio.n to the above-me.ntio.ned three indis-pe.nsable compone.nts9 the photoconductive composition of the prese.nt invention may further comprise known additives according to need. As such additives9 there 2~ can be me.ntioned9 for example9 a bi.nder9 a thickener9 a viscosity reduci.ng agent, a saggi.ng preventi.ng age.nt9 a leveling age.nt9 a defoaming age.nt a.nd a dye sensitizer.
The photoconductive composition of the prese.nt inve.n-tion is dissolved or dispersed i.n an organic solvent to form a coati.ng composition9 and the coating composition is applied to a conductive substrate and dried thereon to form a photosensitive plate for electrophotography.
As the solve.nt that is used for formi.ng a coati.ng co~.position9 there can be mentioned9 for example, aro~atic hydrocarbon solve.nts such as benzene, toluene a.nd xylene, cyclic ethers such as dioxa.ne a.r,d tetrahydrofuran9 ketones such as methylethyl ketone9 methylisobutyl ketone and cyclohexa.none, alcohols such as diacetone alcohol9 ethylene glycol a.nd isobutyl ether9 and ali-cyclic hydrocarbons such as cyclohexa.ne. These solve.nts may be used ~ngly or i.n the form of mixtures of two or more of them.
This coating composition ca.n easily be prepared by forming a solution of the organic polymeric photo-conductor in an organic solvent a-nd a dispersion of phthalocyanine or its derivative in an organic solve.nt, mixi.ng the solution and dispersi~n a.nd addi.ng the aromatic polycyclic nitro compound into the resulting mixture or the above-me.ntio.ned solution or dispersion. From the viewpoi.nt of the adaptability to the coati.ng operation9 it is preferred that the solid content of the so formed coating composition be 1 to 50 %9 especially 5 to 30 %.
As the conductive substrate9 a foil or plate of copper, aluminum, silver, tin~ iron or the like is used i.n the form of a sheet or drum. Alternately9 a product formed by applying such metal in the form of a film to a plastic film or the like by vacuum deposition or nonelectrolytic plating can be used as the co.nductive substrate.
The photoconductive composition of the present inve.ntio:n can be coated on the conductive substrate in ~900 the form of a layer ha~ing a thic~ness of 2 to 20 ~, especially 3 to 10 ~9 as measured as the solid.
In a photosensitive material formed by usi.ng the photoconductive composition of the prese.nt invention~
the electric a.nd photoco.nductive characteristics in electrophotography of the type where the photosensitive material is repeatedly used are remarkably improved and simultaneously, the mechanical properties of the photo-sensitive material, such as the peel resistance can also be remar~ably improved. More specifically, in case of a photosensitive material comprising a single photoco.nduc-tive layer composed of phthalocyanine or its derivative, the aromatic polycyclic nitro compound and the polymeric photocanductor, peeling of the photoconductive layer is not caused at all at the pressure-se.nsitive tape peel test described hereinafter, and a high abrasio.n resistance can be attained. Thus, it is evident that the mechanical properties of the photosensitive material can be promine.ntly improved by usi.ng the photoconductive composition of the prese.nt i.nve.ntion.
The photoconductive composition o~ the prese.nt inve.ntio.n is especially suitable for formation of a photosensitive material to be used in an electrophoto-graphic copying machine of the type where the surface of the photose.nsitive material is negatively charged a.nd reproductio.n is carried out by using the photosensitive material repeatedly while utilizing all the rays of the visible region.
llZ7900 A photoconductive layer formed by using the photoconductive composition of the prese.nt in~ention shows excellent electrophotographic and electric characteristics as shown in Table 1 given herei.nafter9 also whe.n it is positively charged. Accordi:ngly9 the photoco.nductive composition of the prese.nt i.nve.ntio.n can be advantageously applied to formation of a photo-sensitive material to be used in electrophotographic reproductio.n in wllich the photoco.nductive layer is positively charged.
Known two-component type developers and known one-compo.ne.nt type magnetic developers can be used for developing a late.nt image formed on the photoconductive layer.
The present inventio.n will now be described i.n detail by refere.nce to the following Examples that by no mea.ns limit the ~ ope of the inve.ntion.
In the Examples9 all of 1I parts " and " % " are by weight unless otherwise i.ndicated.
Example 1 To 10 parts of polyvinyl carbazole ( Luvican~M-170 manufactured by BASF9 herei.nafter referred to as " PVK " ) was added 90 parts of tetrahydrofuran to form a solution contai.ni.ng 10 % of PVK in tetrahydrofuran.
The.n9 99 parts of tolue:ne was added to 1 part of metal-free phthalocyanine ( Heliogen Blue 7800 ma.nufac-tured by B~SF )9 and the phthalocya:nine was sufficiently dispersed in toluene by an ultrasonic vibrating dis-persing machine to form a 1 % dispersion of the ~-trc~d~na~ _ 22 -phthalocyani.ne.
To 10 parts of the above-me.ntio.ned 10 % PVK solu-tion were added 0.6 part of 274,7-trinitro-9-fluorenone, 1.0 part of the 1 % phthalocya:ni:ne dispersion and 2.0 parts of tetrahydrofuran. The mixture was sufficie.ntly treated by an ultraso.nic vibrati.ng dispersi.ng machine to form a coating compositio.n.
The so formed coating composition was coated o.n an aluminum plate having a thickness of 50 ~ by means of a wire bar9 a.nd dried at 50 C. for 3 minutes and forcibly dried at 120C for 2 mi.nutes, to obtain a photose.nsitive plate comprising a photoconductive layer havi.ng a thick-ness of 4 ~ after drying.
The charge characteristics of the so prepared photosensitive plate were examined by usi.ng a.n electro-static paper analyzer ( manufactured by Kawaguchi Denki ) to obtai.n results show.n in Table 1 a.nd Fig. 3.
The so prepared photosensitive plate was set at an electrophotographic copying machine ( Denshi Copystar~
251-R manufactured by Mita I.ndustrial Company ) a.nd was charged at an applied voltage of - 7 KV, and development was carried out accordi.ng to the magnetic brush method.
A clear image having a high density a.nd being free from foggi.ng can be obtained. When this photose.nsitive plate was subjected to the durability test9 it was found that scores of thousands of prints could be obtained by usi.ng this photose.nsitive plate repeatedly.
ExamPle 2 -aclernc~k 1~
To 1 part of copper phthalocyani.ne ( Cyanine Blue BB manufactured by Dai.nippon I.nk Kagaku Kogyo ) was added 99 parts of tolue.ne, and the phthalocya:nine was sufficie.ntly dispersed i.n toluene by an ultrasonic vibrati,ng dispersing machine9 to form a 1 % dispersion of copper phthalocyani.ne.
To 10 parts of a 10 % PVK solution prepared in the same manner as described in Example 19 0.4 part of 294~7-trinitro~9-fluorenone9 1.0 part of the above 1 %
dispersion of copper phthalocyani,ne and 2.0 parts of tetrahydrofura:n were added to form a coati.ng composi-tion, Then~ a sample was prepared by usi.ng this coati.ng composition in the same ma.n.ner as described in Example 1.
The so prepared sample was set at an electrophoto-graphic copyi.ng machine ( De.nshi Copystar 251-R ma.nufac-tured hy Mi,ta I.ndustrial Company )9 a.nd it was charged at an applied voltage of - 7 KV and exposed to light a.nd developme.nt was carried out accordi,ng to the magnetic brush method. A clear and sharp image free from fogging was obtained.
Exam~le 3 To 10 parts of poly-N-acrylphenothiazine was added 90 parts of tetrahydrofuran to form a solutio.n containing 10 /0 of poly-N-acrylphe,nothiazine in tetrahydrofuran.
To 10 parts of the so prepared solution were added 0.5 part of 2~497-trinitro-9-fluore.no.ne9 O.g part of a 1 /0 phthalocyanine dispersion prepared in the same man.ner as described in Exa.mple 1 and 3.0 parts of ` ~79QO , tetrahydrofuran to form a coati:ng composition9 and by using this coating compositio.n9 a sample was prepared in the same manner as described i.n Example 1.
The sample was set at an electrophotographic copyi.ng machine ( De.nshi Copystar 251-R manufactured by Mita I.ndustrial Co. )9 and it was charged at an applied voltage of - 7.5 KV and developme.nt was carried out accordi.ng to the magnetic brush method after exposure to light. A clear and sharp image free from fogging was obtai.ned.
ExamPle 4 To 10 parts of a 10 % PVK solution prepared in the same ma.nner as described i.n Example 1, 0.4 part of 2~49597-tetranitro-9-fluorenone, 1.5 parts of a phthalo-cyanine dispersion prepared i.n the same manner as des-cribed i.n Example 1 ~nd 2.0 parts of tetrahydrofuran were added to form a coati.ng composition. By using this coating composition9 a sample was prepared in the same ma.n.ner as described i.n Example 1.
The sample was set at a.n electrophotographic copyi.ng machine ( Denshi Copystar 251-R manufactured by Mita Industrial Company ) 9 a.nd it was charged at a.n applied voltage of - 7~5 KV and exposed to light a.nd development was carried out accordi.ng to the magnetic brush method. A clear and sharp image free from fogging was obtained.
Example 5 A photosensitive plate was prepared in the same ~Z7900 ma.nner as described in Ex~mple 1 except that chlorinated polyvinyl carbazole ( manufactured by Takasago Koryo Compa.ny ) was used instead of tne polyvi.nyl carbazole used in Example 1 ( Luvican M-170 ma.nufactured by BASF )9 a.nd this photosensitive plate was tested in the same ma:nner as described i.n Example 1. Good results similar to those obtained i.n Example 1 were obtai.ned.
Example 6 A photosensitive plate was prepared i.n the same ma.nner as described in Example 1 except that poly-N-vi.nyl-396-dibroms carbazole was used i.nstead of the poly-vi.nyl carbazole used in Example 1 ( Luvica.n M-170 manufactured by BASF ). The photosensitive plate was tested in the same ma.nner as described i.n Example 1.
An excellent image similar to that obtained in Example 1 was obtained3 and it was found that the photosensitive plate was excellent i.n the durability ( the resista.nce to the repeated copying operation ).
Example 7 A photosensitive plate was prepared in the same ma~ner as described in Example 1 except that poly-N-allylcarbazole was used instead of the polyvinyl carba-zole used in Example 1 ( Luvican M-170 manufactured by BASF ) and Sumitone~Cyani.ne Blue LG ( manufactured by Sumitomo Kagaku Kogyo ) was used as the metal-free phthalocyanine instead of Heliogen Blue 7800 used in Example 1. When the characteristics of the photosensi-tive plate were tested in the same manner as described in Example 1~ good results were obtained.
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`~79~
Example 8 A photosensitive plate was prepared in the same ma.nner as described in Example 1 except that chlori.nated polyvinyl carbazole was used i.nstead of polyvinyl carbazole ( Luvican M-170 ) and 494'-dinitrobiphe.nyl was used instead of 29497-trinitro-9-fluorenone.
Properties of the so prepared photosensitive plate were tested in the same manner as described in Example 1.
Good results similar to those obtained in Example 1 were obtained.
Comparative Example 1 To 10 parts of a 10 % PVK solution prepared in the same manner as described i.n Example 19 0.6 part of 2,4,7-trinitro-9-fluorenone a.nd 2.0 parts of tetrahydrofura.n were added a.nd they were sufficiently dispersed by an ultrasonic vibration dispersi.ng machine to form a coati.ng composition.
A sample was prepared by using this coating compo-sition i.n the same manner as described in Example 1.
Charge characteristics of the sample were tested in the same manner as described in Example 1 to obtain results shown in Table 1 and Fig. 3.
The sample W2S set at a:n electrophotographic copying machine ( De.nshi Copystar 251-R manufactured by Mita Industrial Company ), and it was charged at an applied voltage of - 5.5 KV9 exposed and developed according to the magnetic brush method. The obtained image was full of foggi.ng9 and appearance of foggi.ng could not be avoided ~9oo even if the exposure quantity was elevated to a maximum level.
Com~rative Example 2 To a 10 % PVK solution prepared i.n the same ma.nner as described i.n Example 1, 4 parts of a 1 ~ phthalocyanine dispersio.n prepared in the same man.ner as described in Example 1 and 2 parts of tetrahydrofuran were added and they were sufficie.ntly dispersed by a:n ultrasonic vibra-ting machine to form a coating composition.
By usi.ng the so prepared coati.ng composition, a sample was prepared in the same manner as described in Example 1.
Charge characteristics of the sample were tested in the same man.ner as described in Example 1 to obtain results shown in Table 1 a.nd Fig. 3.
The sample was set at a.n electrophotographic copying ~chine ( Denshi Copystar 251-R rna.nufactured by Mita I.ndustrial Company )9 and it was charged at an applied voltage of - 6.0 KV, exposed to light a.nd develo-ped accordi.ng to the magnetic brush method. The obtained image was not clear a.nd was full of fogging9 and .no definite disti:nction was observed betwee.n the image area and the :non-image area ( the contrast was very low ).
Comparative Example ~
To 10 parts of 29497-trinitro-9-fluorenone was added 40 parts of tetrahydrofura.n9 a.nd the fluorenone was sufficiently dissolved in tetrahydrofuran. Then, a solution of 0.5 part of copper phthalocyanine in 20 ~7900 parts of toluene was added to the above solution. The resulting mixture was pulverized in a ball mill for 1 hour to form a fine suspensiOn. In the same ma.nner as described in Example 19 the suspe.nsion was coated on alumi.num and dried i.n air at 110C. for 12 hours to form a coating layer havi.ng a thickness of 5 ~ after drying.
Charge characteristics of the so prepared sample were measured in the same ma.nner as described in Example 1 to obtain results shown in Table 1 a.nd Fig, 3.
The sample was set at an electrophotographic copyi.ng machine ( Denshi Copystar 251-R manufactured by Mita Industrial Compa.ny ) 9 and it was charged at an applied voltage of - 7.0 KV, exposed to light and developed according to the magnetic brush method. The obtai.ned image had a low density and was full of foggi.ng. Further9 the resolving power was insufficie.nt and the disorder of the image owi.ng to peeling of the photoconductive layer was observed.
Comparative ExamPle 4 To a 10 % PVK solution prepared in the same ma.nner as de.scribed in Example 19 0.6 part of 29497-trinitro-9-fluoreno:ne a.nd 7 parts of a 1 % phthalocyanine disper-sion prepared in the same ma~ner as described i.n Example 1 were added and they were sufficie.ntly dispersed by an ultrasonic vibrati.ng dispersi.ng machine to form a homogeneous coati.ng composition.
By usi.ng the so prepared C02ti~g composition9 a sample ( photosensitive plate ) was prepared in the same ~27~00 manner as described in Example 1.
Charge characteristics of the so prepared sample were tested in the same ma.nner as described in Example 1 to obtain results shown i.n Table 1 and Fig. 3.
The sample was set at an electrophotcgraphic copying machine ( Denshi Copystar 251-R manufactured by Mita Industrial Company )9 a.nd it was charged at an applied voltage of - 8.0 KV9 exposed to light and developed according to the magn~tic brush method. An image could :not be formed because of insufficient chargin~.
Comparative Example 5 To a 10 % PVK solution prepared i.n the same ma:nner as described in Example 19 o.6 part of 2,4,7-trinitro-9-fluoreno.ne, 0.1 part of a 1 % pm halocyanine dispersion prepared in the same ma.~ner as described in Example 1 a.nd 3,0 parts of tetrahydrofuran were added a.nd they were sufficie.ntly dispersed by an ultrasonic vibrating dispersing machine to form a coating compo-sition.
By using the so prepared coating composition, a sample (-photosensitive plate ) was prepared in the same manner as described in Example 1.. Charge characteristics of the sample were measured in the same mA.nner as des-cribed in Example 1 to obtain results show.n in Table 1 a.nd Fig. 3.
The sample was set at an electrophotographic copying machi.ne ( Denshi Copystar 251-R manufactured by Mita Industrial Company )g and it was charged at an applied ~7go0 voltage of - 6.7 KVg exposed to light and developed according to the magnetic brush method. The resulti.ng image was not clear a.nd was full of fogging, a.nd .no definite distinction was observed betwee.n the image area and the .nonimage area.
Comparative Example 6 To 10 parts of a 10 ~ P.VK solution prepared in the same manner as described in Example 19 1.4 parts of 2,4~7-tri.nitro-9-fluorenone9 1.0 part of a 1 % phthalo-cyanine dispersion prepared in the same manner as des-cribed in Example 1 and 2 parts of tetrahydrofuran were added and they were sufficie.ntly dispersed by an ultra-so.nic vibrati.ng dispersing machine to form a coati.ng composition.
By usi.ng the so prepared coati.ng compositio.n, a sample was prepared in the same manner as described i.n Example 1 Charge characteristics of the sample were measured in the same ma.nner as described in Example 1 to obtain results shown in Table 1 and Fig. 3.
The sample was set at an electrophotographic copy-ing machine ( Denshi Copystar 251-R manufactured by Mita Industrial Company )g and it was charged at an applied voltage of - 7.0 KV9 exposed to light and developed according to the magnetic brush method. The image den-sity was low and the image was not clear a.nd was full of foggi.ng.
Comparative ExamPle 7 To 10 parts of a 10 % PVK solution prepared in the ~moo same manner as described in Example 19 0.1 part of 2~4,7-tri.nitro-9-fluore.none, 1.0 part of a phthalocya.nine dispersion prepared i.n the same ma.nner as described i.n Example 1 and 2 parts of tetrahydrofuran were added a.nd they were sufficiently dispersed by an ultrasonic vibrating dispersi.ng machi.ne to from a coati.ng composi-tion.
By using the so prepared coating composition9 a sample was prepared i.n the same ma.nner as described in Exa.mple 1. The sample was set at an electrophotographic copying machine ( Denshi Copystar 251-R ma.nufactured by Mita Industrial Company )~ and it was charged at an applied voltage of - 6.5 KV9 exposed to light and developed according to the magnetic brush method. The obtained image was not clear and was full of fogging, a.nd no definite distinction was observed between the image area and the nonimage ~rea.
ComE~_ative Example 8 To 85 parts of a 10 % PVK solution prepared in the same manner as described in Example 1, 0.5 part of 29 /~9 7-trinitro-fluorenone and 21 parts of ~ 10 % phtha-:locya.nine dispersion ( the solve.nt bei.ng tolue.ne ) prepared i.n -the same manner as described in Example 1, a.nd 20 parts of tetrahydrofura.n was further added thereto, The mixture was treated by an ultrasonic vibrating dispersing m~chine to form a homoge.neous coat-ing composition.
A sample ( photosensitive plate ) was prepared by - ,2 -~27900 using the so prepared coating composition in the same ma.nner as described i.n Example 1. Charge characteristics of the sample were measured in the same manner as described in Example 1 to obtain results shown in Table 1 and Fig. 3.
This sample was set at a.n electrophotographic copyi.ng machi.ne ( Denshi Copystar 251-R manufactured by Mita T:ndustrial Compa.ny ), and it was charged at an applied voltage of - 8.0 KY9 exposed to light a-nd developed according to the mag.netic brush method. The charging failed to provide a pote.ntial e-.nabling deve-lopment, and the se.nsitivity was ver~ poor and a copy havi.ng slight fogs alone was obtained~ ~urther, the peel stre.ngth of the photoconductive layer in the photosensitive plate was very low and great care had to be taken in ha:ndling the photosensitive plate.
Comparative E~ e 9 A coating composition was prepared i:n the same manner as described in Comparative Example 8 except that the amount of the phthalocya.nine dispersio.n was cha.nged to 1 part a.nd the amount of tetrahydrofuran was changed to 30 parts. A sample ( photosensitive plate ) was prepared by using the so prepared coati.~g composition in the same manner as in Comparative Example 8. Charge characteristics of the sample were me~sured in the same ma:n:ner as described in Example 1 to obtain results shown in Table 1 and Fig. 3.
The so prepared sample was set at an electrophoto-graphic copying machine ( De.nshi Copystar 251-R manufac-tured by Mita Industrial Company )9 a-.nd it was charged at an applied voltage of - 7.0 KV9 exposed to light and developed accordi.ng to the mag.netic brush method. The obtained image was full of foggi.ng a.nd no definite disti.nction was observed between the image area a.nd the nonimage area ( the contrast was very low ).
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~goo Note The image quality and adhesion referred to in Table 1 were evaluated according to the followi:ng standards.
Sharpness:
The sharpness was evaluated based on reproducibility of fine lines9 mesh, halft.one a.nd small letters in the image according to the followi.ng scale:
0: good ~: slightly bad X o bad Density:
The density was evaluated based on the degree of the density or light.ness i.n the image area ( unexposed area ) according to the following scale:
O o de.nse ~: slightly light X 0 light Fogg ing ~
The foggi.ng was evaluated based on the degree of contami:natio.n of the backgrou:nd in the nonimage area ( exposed area ) accordi.ng to the following scale:
O ~ no contami.nation /\: slight contami.nation X : apparent contamination AdhesionO
The adhesion was evaluated accordi.ng to the pressure_sensitive tape peeling test.
O 0 not peeled 1~9~0 ~: slightly peeled X : readily peeled ExamPle 9 A photosensitive plate prepared in the same manner as described in Example 1 was charged at an applied voltage of + 6.5 KV by corona discharge, and it was the.n exposed to light through a.n original and develop-me.nt was carried out by usi.ng a one-compone.nt type magnetic toner. The toner image was transferred at an applied voltage of + 5.4 KV and the transferred toner image was fixed under application of pressure. A clear and sharp image having a high density and bei-.ng free from fogging was obtained.
E _ ple 10 A copied image was formed in the same manner as described in Example 9 except that the fixation of the tra.nsferred image was carried out by usi.ng a heated roll and the to.ner was ch~nged to a one-component type mag.netic toner for heated roll fixation The obtained image had a high density a.nd was very clear and sharp, a.nd occurrence of foggi.ng was not observed at all.
diphe:nylocta-azophthalocya.nine9 tetra-(6-methyl-be.nzo-thiazoyl)phthalocya.nine9 tetra-p-methylphenylaminoph-thalocyani.ne9 tetramethylphthalocyanine9 tetra-4-naphthotriazolphthalocyanine9 tetra-4-naphthylphtha-locyanine9 tetra-L.-.nitrophthalocyani.ne9 tetraperinaph-thylene-4,5-octa-azophthalocyani.ne9 tetra-2,3-phe.nylene-oxide-phthalocyanine9 tetra-4-phenylocta-azophthalocya.ni.ne9 tetraphenylphthalocyanine9 tetra-phe.nylphthalocyani.ne-tetracarboxylic acid, tetraphenyl-phthalocyan:ine tetrabarium carboxylate9 tetra-4-trifluro-methylmercaptophth~locya.nine9 tetrapyridylphthalocyanine, tetra-4-trifluoromethylmercaptophthalocyanine, tetra-4-trifluoromethylphth~locyanine-4,5-thio.n2phthene-octa-azophthalocyanine, platinum phthalocyanine9 potassium phthalocya.nine9 thodium phthalocyanine9 samarium phthalo-cyanine, silver phthalocyanine9 silicon phthalocyanine,sodium phthalocyanine9 sulfonated phthalocyanine, thorium phthalocya.ni.ne9 thulium phthalocyanine9 tin chlorophthalocyanine9 tin phthalocyanine, titanium phthalocya.ni.ne9 uranium phthalocyanine9 vanadium phtha-locya.nine9 zi.nc chlorophthalocyanine9 zinc phthalocyanine,and dimers9 trimers9 oligomers9 homopolymers and copolymers thereof Metal-free phthalocya.nines and nuclear substitution products thereof9 for example, haloge.n .nuclear substitution products thereof, are easily available and especially suitable for attaining the objects of the present invention.
I.n the prese.nt inve.ntion9 it is very important that the electron-accepti.ng aromatic polycyclic .nitro compound should be used in an amou.nt of 0.15 to 0.45 mole per mole of the constituent monomer of the electro.n-do.nati.ng organic polymeric photoco.nductor and that pm halocyanine or its derivative should be used in an amount of 0.2 to 4 % by weight based on the organic polymeric photoconduc-tor.
Whe.n the amount of the phthalocyanine is below the above range9 the sensitivity to light is reduced and the residual pote.ntial after exposure is readily i.ncreased.
When the amou.nt of the phthalocya.nine exceeds the above range9 the saturation charge voltage is lowered a.nd also the sensitivity to light is reduced. Further9 a composi-tio.n comprisi.ng the phthalocya.ni.ne i.n too large an amount is poor i.n th@ coating-forming property a.nd i.n this composition9 there is observed a te.nde.ncy that the mechanical strength or ~dhesion of the coating is insufficient.
When the amou.nt of the aromatic polycyclic nitro compound is below the above range9 the sensitivity to light is reduced and increase of the residual potential after exposure is conspicuous. When the amount of the aromatic polycyclic nitro compound exceeds the above range9 the saturation charge voltage is drastically ~Z7XIV
reduced.
As will be apparent from the foregoing, whe.n TNF
or Pc is incorporated i.nto an organic polymeric photo-conductor9 if the amount i.ncorporated is small, the se.nsitivity is low a.nd the residual pote.ntial is increased. On the other hand9 if the amount i.ncorpora ted is increasedg the saturation charge voltage te.nds to decrease~
I.n co.ntrast9 if both the aromatic polycyclic nitro compound a.nd phthalocyani.ne or its derivative are incorporated in combi.nation in specific small amounts accordi.ng to the present i.nvention, it is made possible to satisfy two co.ntradictory requirements, namely increase of the saturation charge voltage a.nd reduction of the residual pote.ntial.
I.n additio.n to the above-me.ntio.ned three indis-pe.nsable compone.nts9 the photoconductive composition of the prese.nt invention may further comprise known additives according to need. As such additives9 there 2~ can be me.ntioned9 for example9 a bi.nder9 a thickener9 a viscosity reduci.ng agent, a saggi.ng preventi.ng age.nt9 a leveling age.nt9 a defoaming age.nt a.nd a dye sensitizer.
The photoconductive composition of the prese.nt inve.n-tion is dissolved or dispersed i.n an organic solvent to form a coati.ng composition9 and the coating composition is applied to a conductive substrate and dried thereon to form a photosensitive plate for electrophotography.
As the solve.nt that is used for formi.ng a coati.ng co~.position9 there can be mentioned9 for example, aro~atic hydrocarbon solve.nts such as benzene, toluene a.nd xylene, cyclic ethers such as dioxa.ne a.r,d tetrahydrofuran9 ketones such as methylethyl ketone9 methylisobutyl ketone and cyclohexa.none, alcohols such as diacetone alcohol9 ethylene glycol a.nd isobutyl ether9 and ali-cyclic hydrocarbons such as cyclohexa.ne. These solve.nts may be used ~ngly or i.n the form of mixtures of two or more of them.
This coating composition ca.n easily be prepared by forming a solution of the organic polymeric photo-conductor in an organic solvent a-nd a dispersion of phthalocyanine or its derivative in an organic solve.nt, mixi.ng the solution and dispersi~n a.nd addi.ng the aromatic polycyclic nitro compound into the resulting mixture or the above-me.ntio.ned solution or dispersion. From the viewpoi.nt of the adaptability to the coati.ng operation9 it is preferred that the solid content of the so formed coating composition be 1 to 50 %9 especially 5 to 30 %.
As the conductive substrate9 a foil or plate of copper, aluminum, silver, tin~ iron or the like is used i.n the form of a sheet or drum. Alternately9 a product formed by applying such metal in the form of a film to a plastic film or the like by vacuum deposition or nonelectrolytic plating can be used as the co.nductive substrate.
The photoconductive composition of the present inve.ntio:n can be coated on the conductive substrate in ~900 the form of a layer ha~ing a thic~ness of 2 to 20 ~, especially 3 to 10 ~9 as measured as the solid.
In a photosensitive material formed by usi.ng the photoconductive composition of the prese.nt invention~
the electric a.nd photoco.nductive characteristics in electrophotography of the type where the photosensitive material is repeatedly used are remarkably improved and simultaneously, the mechanical properties of the photo-sensitive material, such as the peel resistance can also be remar~ably improved. More specifically, in case of a photosensitive material comprising a single photoco.nduc-tive layer composed of phthalocyanine or its derivative, the aromatic polycyclic nitro compound and the polymeric photocanductor, peeling of the photoconductive layer is not caused at all at the pressure-se.nsitive tape peel test described hereinafter, and a high abrasio.n resistance can be attained. Thus, it is evident that the mechanical properties of the photosensitive material can be promine.ntly improved by usi.ng the photoconductive composition of the prese.nt i.nve.ntion.
The photoconductive composition o~ the prese.nt inve.ntio.n is especially suitable for formation of a photosensitive material to be used in an electrophoto-graphic copying machine of the type where the surface of the photose.nsitive material is negatively charged a.nd reproductio.n is carried out by using the photosensitive material repeatedly while utilizing all the rays of the visible region.
llZ7900 A photoconductive layer formed by using the photoconductive composition of the prese.nt in~ention shows excellent electrophotographic and electric characteristics as shown in Table 1 given herei.nafter9 also whe.n it is positively charged. Accordi:ngly9 the photoco.nductive composition of the prese.nt i.nve.ntio.n can be advantageously applied to formation of a photo-sensitive material to be used in electrophotographic reproductio.n in wllich the photoco.nductive layer is positively charged.
Known two-component type developers and known one-compo.ne.nt type magnetic developers can be used for developing a late.nt image formed on the photoconductive layer.
The present inventio.n will now be described i.n detail by refere.nce to the following Examples that by no mea.ns limit the ~ ope of the inve.ntion.
In the Examples9 all of 1I parts " and " % " are by weight unless otherwise i.ndicated.
Example 1 To 10 parts of polyvinyl carbazole ( Luvican~M-170 manufactured by BASF9 herei.nafter referred to as " PVK " ) was added 90 parts of tetrahydrofuran to form a solution contai.ni.ng 10 % of PVK in tetrahydrofuran.
The.n9 99 parts of tolue:ne was added to 1 part of metal-free phthalocyanine ( Heliogen Blue 7800 ma.nufac-tured by B~SF )9 and the phthalocya:nine was sufficiently dispersed in toluene by an ultrasonic vibrating dis-persing machine to form a 1 % dispersion of the ~-trc~d~na~ _ 22 -phthalocyani.ne.
To 10 parts of the above-me.ntio.ned 10 % PVK solu-tion were added 0.6 part of 274,7-trinitro-9-fluorenone, 1.0 part of the 1 % phthalocya:ni:ne dispersion and 2.0 parts of tetrahydrofuran. The mixture was sufficie.ntly treated by an ultraso.nic vibrati.ng dispersi.ng machine to form a coating compositio.n.
The so formed coating composition was coated o.n an aluminum plate having a thickness of 50 ~ by means of a wire bar9 a.nd dried at 50 C. for 3 minutes and forcibly dried at 120C for 2 mi.nutes, to obtain a photose.nsitive plate comprising a photoconductive layer havi.ng a thick-ness of 4 ~ after drying.
The charge characteristics of the so prepared photosensitive plate were examined by usi.ng a.n electro-static paper analyzer ( manufactured by Kawaguchi Denki ) to obtai.n results show.n in Table 1 a.nd Fig. 3.
The so prepared photosensitive plate was set at an electrophotographic copying machine ( Denshi Copystar~
251-R manufactured by Mita I.ndustrial Company ) a.nd was charged at an applied voltage of - 7 KV, and development was carried out accordi.ng to the magnetic brush method.
A clear image having a high density a.nd being free from foggi.ng can be obtained. When this photose.nsitive plate was subjected to the durability test9 it was found that scores of thousands of prints could be obtained by usi.ng this photose.nsitive plate repeatedly.
ExamPle 2 -aclernc~k 1~
To 1 part of copper phthalocyani.ne ( Cyanine Blue BB manufactured by Dai.nippon I.nk Kagaku Kogyo ) was added 99 parts of tolue.ne, and the phthalocya:nine was sufficie.ntly dispersed i.n toluene by an ultrasonic vibrati,ng dispersing machine9 to form a 1 % dispersion of copper phthalocyani.ne.
To 10 parts of a 10 % PVK solution prepared in the same manner as described in Example 19 0.4 part of 294~7-trinitro~9-fluorenone9 1.0 part of the above 1 %
dispersion of copper phthalocyani,ne and 2.0 parts of tetrahydrofura:n were added to form a coati.ng composi-tion, Then~ a sample was prepared by usi.ng this coati.ng composition in the same ma.n.ner as described in Example 1.
The so prepared sample was set at an electrophoto-graphic copyi.ng machine ( De.nshi Copystar 251-R ma.nufac-tured hy Mi,ta I.ndustrial Company )9 a.nd it was charged at an applied voltage of - 7 KV and exposed to light a.nd developme.nt was carried out accordi,ng to the magnetic brush method. A clear and sharp image free from fogging was obtained.
Exam~le 3 To 10 parts of poly-N-acrylphenothiazine was added 90 parts of tetrahydrofuran to form a solutio.n containing 10 /0 of poly-N-acrylphe,nothiazine in tetrahydrofuran.
To 10 parts of the so prepared solution were added 0.5 part of 2~497-trinitro-9-fluore.no.ne9 O.g part of a 1 /0 phthalocyanine dispersion prepared in the same man.ner as described in Exa.mple 1 and 3.0 parts of ` ~79QO , tetrahydrofuran to form a coati:ng composition9 and by using this coating compositio.n9 a sample was prepared in the same manner as described i.n Example 1.
The sample was set at an electrophotographic copyi.ng machine ( De.nshi Copystar 251-R manufactured by Mita I.ndustrial Co. )9 and it was charged at an applied voltage of - 7.5 KV and developme.nt was carried out accordi.ng to the magnetic brush method after exposure to light. A clear and sharp image free from fogging was obtai.ned.
ExamPle 4 To 10 parts of a 10 % PVK solution prepared in the same ma.nner as described i.n Example 1, 0.4 part of 2~49597-tetranitro-9-fluorenone, 1.5 parts of a phthalo-cyanine dispersion prepared i.n the same manner as des-cribed i.n Example 1 ~nd 2.0 parts of tetrahydrofuran were added to form a coati.ng composition. By using this coating composition9 a sample was prepared in the same ma.n.ner as described i.n Example 1.
The sample was set at a.n electrophotographic copyi.ng machine ( Denshi Copystar 251-R manufactured by Mita Industrial Company ) 9 a.nd it was charged at a.n applied voltage of - 7~5 KV and exposed to light a.nd development was carried out accordi.ng to the magnetic brush method. A clear and sharp image free from fogging was obtained.
Example 5 A photosensitive plate was prepared in the same ~Z7900 ma.nner as described in Ex~mple 1 except that chlorinated polyvinyl carbazole ( manufactured by Takasago Koryo Compa.ny ) was used instead of tne polyvi.nyl carbazole used in Example 1 ( Luvican M-170 ma.nufactured by BASF )9 a.nd this photosensitive plate was tested in the same ma:nner as described i.n Example 1. Good results similar to those obtained i.n Example 1 were obtai.ned.
Example 6 A photosensitive plate was prepared i.n the same ma.nner as described in Example 1 except that poly-N-vi.nyl-396-dibroms carbazole was used i.nstead of the poly-vi.nyl carbazole used in Example 1 ( Luvica.n M-170 manufactured by BASF ). The photosensitive plate was tested in the same ma.nner as described i.n Example 1.
An excellent image similar to that obtained in Example 1 was obtained3 and it was found that the photosensitive plate was excellent i.n the durability ( the resista.nce to the repeated copying operation ).
Example 7 A photosensitive plate was prepared in the same ma~ner as described in Example 1 except that poly-N-allylcarbazole was used instead of the polyvinyl carba-zole used in Example 1 ( Luvican M-170 manufactured by BASF ) and Sumitone~Cyani.ne Blue LG ( manufactured by Sumitomo Kagaku Kogyo ) was used as the metal-free phthalocyanine instead of Heliogen Blue 7800 used in Example 1. When the characteristics of the photosensi-tive plate were tested in the same manner as described in Example 1~ good results were obtained.
~a c~ e ~
`~79~
Example 8 A photosensitive plate was prepared in the same ma.nner as described in Example 1 except that chlori.nated polyvinyl carbazole was used i.nstead of polyvinyl carbazole ( Luvican M-170 ) and 494'-dinitrobiphe.nyl was used instead of 29497-trinitro-9-fluorenone.
Properties of the so prepared photosensitive plate were tested in the same manner as described in Example 1.
Good results similar to those obtained in Example 1 were obtained.
Comparative Example 1 To 10 parts of a 10 % PVK solution prepared in the same manner as described i.n Example 19 0.6 part of 2,4,7-trinitro-9-fluorenone a.nd 2.0 parts of tetrahydrofura.n were added a.nd they were sufficiently dispersed by an ultrasonic vibration dispersi.ng machine to form a coati.ng composition.
A sample was prepared by using this coating compo-sition i.n the same manner as described in Example 1.
Charge characteristics of the sample were tested in the same manner as described in Example 1 to obtain results shown in Table 1 and Fig. 3.
The sample W2S set at a:n electrophotographic copying machine ( De.nshi Copystar 251-R manufactured by Mita Industrial Company ), and it was charged at an applied voltage of - 5.5 KV9 exposed and developed according to the magnetic brush method. The obtained image was full of foggi.ng9 and appearance of foggi.ng could not be avoided ~9oo even if the exposure quantity was elevated to a maximum level.
Com~rative Example 2 To a 10 % PVK solution prepared i.n the same ma.nner as described i.n Example 1, 4 parts of a 1 ~ phthalocyanine dispersio.n prepared in the same man.ner as described in Example 1 and 2 parts of tetrahydrofuran were added and they were sufficie.ntly dispersed by a:n ultrasonic vibra-ting machine to form a coating composition.
By usi.ng the so prepared coati.ng composition, a sample was prepared in the same manner as described in Example 1.
Charge characteristics of the sample were tested in the same man.ner as described in Example 1 to obtain results shown in Table 1 a.nd Fig. 3.
The sample was set at a.n electrophotographic copying ~chine ( Denshi Copystar 251-R rna.nufactured by Mita I.ndustrial Company )9 and it was charged at an applied voltage of - 6.0 KV, exposed to light a.nd develo-ped accordi.ng to the magnetic brush method. The obtained image was not clear a.nd was full of fogging9 and .no definite disti:nction was observed betwee.n the image area and the :non-image area ( the contrast was very low ).
Comparative Example ~
To 10 parts of 29497-trinitro-9-fluorenone was added 40 parts of tetrahydrofura.n9 a.nd the fluorenone was sufficiently dissolved in tetrahydrofuran. Then, a solution of 0.5 part of copper phthalocyanine in 20 ~7900 parts of toluene was added to the above solution. The resulting mixture was pulverized in a ball mill for 1 hour to form a fine suspensiOn. In the same ma.nner as described in Example 19 the suspe.nsion was coated on alumi.num and dried i.n air at 110C. for 12 hours to form a coating layer havi.ng a thickness of 5 ~ after drying.
Charge characteristics of the so prepared sample were measured in the same ma.nner as described in Example 1 to obtain results shown in Table 1 a.nd Fig, 3.
The sample was set at an electrophotographic copyi.ng machine ( Denshi Copystar 251-R manufactured by Mita Industrial Compa.ny ) 9 and it was charged at an applied voltage of - 7.0 KV, exposed to light and developed according to the magnetic brush method. The obtai.ned image had a low density and was full of foggi.ng. Further9 the resolving power was insufficie.nt and the disorder of the image owi.ng to peeling of the photoconductive layer was observed.
Comparative ExamPle 4 To a 10 % PVK solution prepared in the same ma.nner as de.scribed in Example 19 0.6 part of 29497-trinitro-9-fluoreno:ne a.nd 7 parts of a 1 % phthalocyanine disper-sion prepared in the same ma~ner as described i.n Example 1 were added and they were sufficie.ntly dispersed by an ultrasonic vibrati.ng dispersi.ng machine to form a homogeneous coati.ng composition.
By usi.ng the so prepared C02ti~g composition9 a sample ( photosensitive plate ) was prepared in the same ~27~00 manner as described in Example 1.
Charge characteristics of the so prepared sample were tested in the same ma.nner as described in Example 1 to obtain results shown i.n Table 1 and Fig. 3.
The sample was set at an electrophotcgraphic copying machine ( Denshi Copystar 251-R manufactured by Mita Industrial Company )9 a.nd it was charged at an applied voltage of - 8.0 KV9 exposed to light and developed according to the magn~tic brush method. An image could :not be formed because of insufficient chargin~.
Comparative Example 5 To a 10 % PVK solution prepared i.n the same ma:nner as described in Example 19 o.6 part of 2,4,7-trinitro-9-fluoreno.ne, 0.1 part of a 1 % pm halocyanine dispersion prepared in the same ma.~ner as described in Example 1 a.nd 3,0 parts of tetrahydrofuran were added a.nd they were sufficie.ntly dispersed by an ultrasonic vibrating dispersing machine to form a coating compo-sition.
By using the so prepared coating composition, a sample (-photosensitive plate ) was prepared in the same manner as described in Example 1.. Charge characteristics of the sample were measured in the same mA.nner as des-cribed in Example 1 to obtain results show.n in Table 1 a.nd Fig. 3.
The sample was set at an electrophotographic copying machi.ne ( Denshi Copystar 251-R manufactured by Mita Industrial Company )g and it was charged at an applied ~7go0 voltage of - 6.7 KVg exposed to light and developed according to the magnetic brush method. The resulti.ng image was not clear a.nd was full of fogging, a.nd .no definite distinction was observed betwee.n the image area and the .nonimage area.
Comparative Example 6 To 10 parts of a 10 ~ P.VK solution prepared in the same manner as described in Example 19 1.4 parts of 2,4~7-tri.nitro-9-fluorenone9 1.0 part of a 1 % phthalo-cyanine dispersion prepared in the same manner as des-cribed in Example 1 and 2 parts of tetrahydrofuran were added and they were sufficie.ntly dispersed by an ultra-so.nic vibrati.ng dispersing machine to form a coati.ng composition.
By usi.ng the so prepared coati.ng compositio.n, a sample was prepared in the same manner as described i.n Example 1 Charge characteristics of the sample were measured in the same ma.nner as described in Example 1 to obtain results shown in Table 1 and Fig. 3.
The sample was set at an electrophotographic copy-ing machine ( Denshi Copystar 251-R manufactured by Mita Industrial Company )g and it was charged at an applied voltage of - 7.0 KV9 exposed to light and developed according to the magnetic brush method. The image den-sity was low and the image was not clear a.nd was full of foggi.ng.
Comparative ExamPle 7 To 10 parts of a 10 % PVK solution prepared in the ~moo same manner as described in Example 19 0.1 part of 2~4,7-tri.nitro-9-fluore.none, 1.0 part of a phthalocya.nine dispersion prepared i.n the same ma.nner as described i.n Example 1 and 2 parts of tetrahydrofuran were added a.nd they were sufficiently dispersed by an ultrasonic vibrating dispersi.ng machi.ne to from a coati.ng composi-tion.
By using the so prepared coating composition9 a sample was prepared i.n the same ma.nner as described in Exa.mple 1. The sample was set at an electrophotographic copying machine ( Denshi Copystar 251-R ma.nufactured by Mita Industrial Company )~ and it was charged at an applied voltage of - 6.5 KV9 exposed to light and developed according to the magnetic brush method. The obtained image was not clear and was full of fogging, a.nd no definite distinction was observed between the image area and the nonimage ~rea.
ComE~_ative Example 8 To 85 parts of a 10 % PVK solution prepared in the same manner as described in Example 1, 0.5 part of 29 /~9 7-trinitro-fluorenone and 21 parts of ~ 10 % phtha-:locya.nine dispersion ( the solve.nt bei.ng tolue.ne ) prepared i.n -the same manner as described in Example 1, a.nd 20 parts of tetrahydrofura.n was further added thereto, The mixture was treated by an ultrasonic vibrating dispersing m~chine to form a homoge.neous coat-ing composition.
A sample ( photosensitive plate ) was prepared by - ,2 -~27900 using the so prepared coating composition in the same ma.nner as described i.n Example 1. Charge characteristics of the sample were measured in the same manner as described in Example 1 to obtain results shown in Table 1 and Fig. 3.
This sample was set at a.n electrophotographic copyi.ng machi.ne ( Denshi Copystar 251-R manufactured by Mita T:ndustrial Compa.ny ), and it was charged at an applied voltage of - 8.0 KY9 exposed to light a-nd developed according to the mag.netic brush method. The charging failed to provide a pote.ntial e-.nabling deve-lopment, and the se.nsitivity was ver~ poor and a copy havi.ng slight fogs alone was obtained~ ~urther, the peel stre.ngth of the photoconductive layer in the photosensitive plate was very low and great care had to be taken in ha:ndling the photosensitive plate.
Comparative E~ e 9 A coating composition was prepared i:n the same manner as described in Comparative Example 8 except that the amount of the phthalocya.nine dispersio.n was cha.nged to 1 part a.nd the amount of tetrahydrofuran was changed to 30 parts. A sample ( photosensitive plate ) was prepared by using the so prepared coati.~g composition in the same manner as in Comparative Example 8. Charge characteristics of the sample were me~sured in the same ma:n:ner as described in Example 1 to obtain results shown in Table 1 and Fig. 3.
The so prepared sample was set at an electrophoto-graphic copying machine ( De.nshi Copystar 251-R manufac-tured by Mita Industrial Company )9 a-.nd it was charged at an applied voltage of - 7.0 KV9 exposed to light and developed accordi.ng to the mag.netic brush method. The obtained image was full of foggi.ng a.nd no definite disti.nction was observed between the image area a.nd the nonimage area ( the contrast was very low ).
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~goo Note The image quality and adhesion referred to in Table 1 were evaluated according to the followi:ng standards.
Sharpness:
The sharpness was evaluated based on reproducibility of fine lines9 mesh, halft.one a.nd small letters in the image according to the followi.ng scale:
0: good ~: slightly bad X o bad Density:
The density was evaluated based on the degree of the density or light.ness i.n the image area ( unexposed area ) according to the following scale:
O o de.nse ~: slightly light X 0 light Fogg ing ~
The foggi.ng was evaluated based on the degree of contami:natio.n of the backgrou:nd in the nonimage area ( exposed area ) accordi.ng to the following scale:
O ~ no contami.nation /\: slight contami.nation X : apparent contamination AdhesionO
The adhesion was evaluated accordi.ng to the pressure_sensitive tape peeling test.
O 0 not peeled 1~9~0 ~: slightly peeled X : readily peeled ExamPle 9 A photosensitive plate prepared in the same manner as described in Example 1 was charged at an applied voltage of + 6.5 KV by corona discharge, and it was the.n exposed to light through a.n original and develop-me.nt was carried out by usi.ng a one-compone.nt type magnetic toner. The toner image was transferred at an applied voltage of + 5.4 KV and the transferred toner image was fixed under application of pressure. A clear and sharp image having a high density and bei-.ng free from fogging was obtained.
E _ ple 10 A copied image was formed in the same manner as described in Example 9 except that the fixation of the tra.nsferred image was carried out by usi.ng a heated roll and the to.ner was ch~nged to a one-component type mag.netic toner for heated roll fixation The obtained image had a high density a.nd was very clear and sharp, a.nd occurrence of foggi.ng was not observed at all.
Claims (4)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A photoconductive composition for electrophotography, which com-prises an electron-donating organic polymeric photoconductor, an electron-accepting aromatic polycyclic compound having at least one nitro-nuclear sub-stituent in an amount of 0.15 to 0.45 mole per mole of the constituent mon-omer of the organic polymeric photoconductor and phthalocyanine or a deriv-ative thereof in an amount of 0.2 to 4% by weight based on the organic poly-meric photoconductor.
2. A photoconductive composition as set forth in claim 1 wherein the organic polymeric photoconductor is polyvinyl carbazole or a nuclear substitution product thereof.
3. A photoconductive composition as set forth in claim 1 wherein the aromatic polycyclic compound is tri- or tetra-nitrofluorenone.
4. A photoconductive composition as set forth in claim 1 wherein the phthalocyanine or its derivative is metal-free phthalocyanine or a nuc-lear substitution product thereof.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8881377A JPS5424026A (en) | 1977-07-26 | 1977-07-26 | Photoconductive composition for electrophotography |
| JP88813/77 | 1977-07-26 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1127900A true CA1127900A (en) | 1982-07-20 |
Family
ID=13953329
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA308,088A Expired CA1127900A (en) | 1977-07-26 | 1978-07-25 | Photoconductive composition containing an organic polymeric photoconductor, an aromatic polycyclic nitro compound and a phthalocyanine |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS5424026A (en) |
| AU (1) | AU517256B2 (en) |
| CA (1) | CA1127900A (en) |
| DE (1) | DE2832859A1 (en) |
| FR (1) | FR2399049A1 (en) |
| GB (1) | GB2002915B (en) |
| IT (1) | IT1097340B (en) |
| NL (1) | NL7807939A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56124277A (en) * | 1980-03-05 | 1981-09-29 | Ricoh Co Ltd | Photovoltaic element using organic compound |
| JPS58184948A (en) * | 1982-04-23 | 1983-10-28 | Hitachi Ltd | Electrophotographic organic photoconductive composition |
| GB2158257B (en) * | 1984-03-09 | 1987-12-31 | Canon Kk | Developing an electrophotographic latent image |
| JP6942717B2 (en) * | 2016-10-14 | 2021-09-29 | 日本曹達株式会社 | Adhesive composition |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB964875A (en) * | 1959-02-26 | 1964-07-22 | Gevaert Photo Prod Nv | Improvements in or relating to electrophotography |
| US3155503A (en) * | 1959-02-26 | 1964-11-03 | Gevaert Photo Prod Nv | Electrophotographic material |
| FR1262155A (en) * | 1959-07-01 | 1961-05-26 | Kalle Ag | Photoconductive layers for electrophotography |
| JPS502580B1 (en) * | 1966-01-03 | 1975-01-28 | ||
| FR91579E (en) * | 1966-01-03 | 1968-07-05 | Rank Xerox Ltd | electrophotographic elements |
| US3484237A (en) * | 1966-06-13 | 1969-12-16 | Ibm | Organic photoconductive compositions and their use in electrophotographic processes |
| FR2095660A5 (en) * | 1970-06-01 | 1972-02-11 | Eastman Kodak Co | Electrophotographic composition of high sensitivity |
| CA971796A (en) * | 1970-12-01 | 1975-07-29 | Robert W. Gundlach | Xerographic binder plate |
| US3897249A (en) * | 1973-04-09 | 1975-07-29 | Xerox Corp | Toners for phthalocyanine photoreceptors |
| JPS5389433A (en) * | 1977-01-17 | 1978-08-07 | Mita Industrial Co Ltd | Photosensitive body for electrophotography |
-
1977
- 1977-07-26 JP JP8881377A patent/JPS5424026A/en active Pending
-
1978
- 1978-07-25 AU AU38316/78A patent/AU517256B2/en not_active Expired
- 1978-07-25 CA CA308,088A patent/CA1127900A/en not_active Expired
- 1978-07-26 NL NL7807939A patent/NL7807939A/en not_active Application Discontinuation
- 1978-07-26 DE DE19782832859 patent/DE2832859A1/en active Granted
- 1978-07-26 IT IT26131/78A patent/IT1097340B/en active
- 1978-07-26 FR FR7822110A patent/FR2399049A1/en active Granted
- 1978-07-26 GB GB7831227A patent/GB2002915B/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| IT7826131A0 (en) | 1978-07-26 |
| GB2002915B (en) | 1982-02-10 |
| JPS5424026A (en) | 1979-02-23 |
| DE2832859C2 (en) | 1988-08-25 |
| AU3831678A (en) | 1980-01-31 |
| AU517256B2 (en) | 1981-07-16 |
| DE2832859A1 (en) | 1979-02-15 |
| IT1097340B (en) | 1985-08-31 |
| FR2399049B1 (en) | 1984-10-26 |
| GB2002915A (en) | 1979-02-28 |
| NL7807939A (en) | 1979-01-30 |
| FR2399049A1 (en) | 1979-02-23 |
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