Source: http://www.google.com/patents/US7186490?dq=6246862
Timestamp: 2017-07-22 03:06:11
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Matched Legal Cases: ['Application No. 62173640', 'Application No. 63129327', 'Application No. 63279663', 'Application No. 01064801', 'Application No. 01170355', 'Application No. 01170360', 'Application No. 01173733', 'Application No. 02068089', 'Application No. 06136636', 'Application No. 56033977', 'Application No. 57142458', 'Application No. 57146538', 'Application No. 57153982', 'Application No. 57159469', 'Application No. 58040798', 'Application No. 60079240', 'Application No. 60205541', 'Application No. 61143445', 'Application No. 61262030', 'Application No. 62027155']

Patent US7186490 - Photosensitive material, electrophotographic photoreceptor using the ... - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inPatentsA titanyl phthalocyanine crystal having an X-ray diffraction spectrum having a plurality of diffraction peaks in which a maximum diffraction peak is observed at a Bragg (2 θ) angle of 27.2°±0.2° and a diffraction peak is observed at a lowest Bragg (2θ) angle of 7.3°±0.2° when a specific X-ray...http://www.google.com/patents/US7186490?utm_source=gb-gplus-sharePatent US7186490 - Photosensitive material, electrophotographic photoreceptor using the material, and electrophotographic image forming method and apparatus using the photoreceptorAdvanced Patent SearchTry the new Google Patents, with machine-classified Google Scholar results, and Japanese and South Korean patents.Publication numberUS7186490 B1Publication typeGrantApplication numberUS 09/566,958Publication dateMar 6, 2007Filing dateMay 8, 2000Priority dateMay 6, 1999Fee statusPaidPublication number09566958, 566958, US 7186490 B1, US 7186490B1, US-B1-7186490, US7186490 B1, US7186490B1InventorsTatsuya Niimi, Tetsuro SuzukiOriginal AssigneeRicoh Company, Ltd.Export CitationBiBTeX, EndNote, RefManPatent Citations (26), Non-Patent Citations (47), Referenced by (9), Classifications (16), Legal Events (3) External Links: USPTO, USPTO Assignment, EspacenetPhotosensitive material, electrophotographic photoreceptor using the material, and electrophotographic image forming method and apparatus using the photoreceptor
US 7186490 B1Abstract
A titanyl phthalocyanine crystal having an X-ray diffraction spectrum having a plurality of diffraction peaks in which a maximum diffraction peak is observed at a Bragg (2 θ) angle of 27.2°±0.2° and a diffraction peak is observed at a lowest Bragg (2θ) angle of 7.3°±0.2° when a specific X-ray of Cu—Kα having a wavelength of 1.514 Å irradiates the titanyl phthalocyanine crystal. A photoreceptor having a photosensitive layer including the titanyl phthalocyanine crystal is also provided.
1. A titanyl phthalocyanine crystal having the X-ray diffraction spectrum of FIG. 8 when a specific X-ray of Cu—Kα having a wavelength of 1.542 Å irradiates the titanyl phthalocyanine crystal.
4. The titanyl phthalocyanine crystal according to claim 2, wherein the amorphous titanyl phthalocyanine wet cake has a maximum diffraction peak at a Bragg (2θ) angle of 7.0±0.2° to 7.5±0.2° and a half-width of not less than 1° after drying.
11. The method according to claim 10, wherein the amorphous titanyl phthalocyanine wet cake has a maximum X-ray diffraction peak at a Bragg (2θ) angle of from 7.0°±0.2° to 7.5°±0.2° after drying.
13. The method according to claim 11, wherein the maximum X-ray diffraction peak of the amorphous titanyl phthalocyanine wet cake has a half width of not less than 1° after drying.
Such problems occur even when the TiOPc crystal having an X-ray diffraction spectrum such that a diffraction peak is observed at a Bragg (2θ) angle of 7.5° is used together with another TiOPc crystal, for example, having a peak at an angle of 27.2°.
Accordingly, an object of the present invention is to provide a photosensitive material which has high photosensitivity and good charge stability even when repeatedly used for a long time.
To achieve these objects, the present invention contemplates the provision of a titanyl phthalocyanine crystal which has an X-ray diffraction spectrum having a plurality of diffraction peaks in which a maximum diffraction peak is observed at a Bragg (2θ) angle of 27.2°±0.2° and a diffraction peak is observed at a lowest Bragg (2θ) angle of 7.3°±0.2° when a specific X-ray of Cu—Kα (wavelength of 1.542 Å) irradiates the titanyl phthalocyanine crystal.
The titanyl phthalocyanine crystal preferably has another diffraction peak at a Bragg (2θ) angle of 9.4°±0.2°, wherein there is preferably no peak between the peak at an angle of 7.3° and the peak at an angle of 9.4°.
The titanyl phthalocyanine crystal may have no peak from 25.5±0.2° to the maximum diffraction peak at a Bragg (2θ) angle of 27.2±0.2°.
The structure of the titanyl phthalocyanine crystal of the present invention is as follows:
The TiOPc crystal of the present invention has at least diffraction peaks at Bragg (2θ) angles of 7.3° and 27.2°. It is not clarified whether a TiOPc crystal having the peak of 27.2° also has the peak of 7.3°, or both a TiOPc crystal having the peak of 27.2° and a TiOPc crystal having the peak of 7.3° are present therein. However, it is clarified by the experiment mentioned below that the TiOPc crystal of the present invention is different from the TiOPc crystal disclosed in Japanese Laid-Open Patent Publication No. 61-239248. In addition, when the TiOPc crystal of the present invention is used for a photoreceptor, such problems mentioned above (i.e., deterioration of the charging ability, and large charge decay in a dark place) do not arise. Therefore, the present invention is different from the known TiOPc crystals.
(1) the solvent of a liquid including a TiOPc pigment is changed; (2) a liquid including a TiOPc pigment is subjected to a mechanical treatment under load conditions; or (3) a sulfuric acid pasting method in which TiOPc having an amorphous crystal form, which is prepared by dissolving titanyl phthalocyanine in sulfuric acid and then adding the solution into water, is subjected to a crystal changing process in which the TiOPc pigment having an amorphous form is contacted with an organic solvent in the presence of water. Among these methods, the method (3) is preferably used for preparing the TiOPc crystal of the present invention. In particular, the TiOPc crystal of the present invention is preferably prepared by changing the crystal form of a TiOPc pigment which has an amorphous form and which has an X-diffraction spectrum in which a maximum peak is observed at an angle of from 7.0° to 7.5°. In addition, the half width of the maximum peak is preferably not less than 1°.
The TiOPc crystal of the present invention has good carrier generation ability. However, the carrier generation ability of the TiOPc crystal is sometimes deteriorated (i.e., the photosensitivity deteriorates or the residual potential increases when repeatedly used) by the charge transport material used in combination therewith depending on the species of the charge transport material. As a result of examination of the present inventor, it is found that the good carrier generation ability can be exerted when the TiOPc crystal is used together with a charge transport material having a specific mobility. In the photoreceptor of the present invention, the mobility of the charge transport material is preferably not less than 1×10−5 cm2/V·sec at a field strength at which a light image is formed on the photoreceptor in an image forming apparatus.
In the present invention, the peak intensity of a peak in the X-ray diffraction spectrum at a Bragg (2θ) angle of, for example, 7.3°, 27.2° and 28.6° is determined as follows:
The charge transport layer 37 includes a low molecular-weight charge transport material and an inactive polymer. The mobility of the charge transport layer is preferably not less than 1×10−5 cm2/V·sec when measured in a field strength which is similar to the field strength applied to the charge transport layer of the photoreceptor used in an image forming apparatus. The field strength in image forming apparatus is about 5×105 (V/cm).
wherein R101 and R102 independently represent a substituted or unsubstituted alkyl group, an aryl group, or a halogen atom; Y represents a linear, branched or a ring alkylene group, —O—, —S—, —SO—, —SO2—, —CO—, or —CO—O—Z—O—CO—, wherein Z represents a divalent aliphatic hydrocarbon group; and s and m is independently 0 or an integer of from 1 to 4, and t is 0 or 1.
The undercoat layer may include a fine powder of metal oxides such as titanium oxide, silica, alumina, zirconium oxide, tin oxide, and indium oxide to prevent the occurrence of moiré in the recorded images and to decrease the residual surface potential of the photoreceptor. The undercoat layer can also be formed by coating a coating liquid using a proper solvent and a proper coating method as mentioned above in the photosensitive layer.
Synthesis Examples 1 to 6 and Comparative Synthesis Examples 1 and 2
In a container, 29.2 g of 1,3-diiminoisoindoline and 200 ml of sulfolane were contained and stirred. Under a nitrogen current, 20.4 g of titanium tetrabutoxide were dropped therein. After titanium tetrabutoxide was added, the temperature of the mixture was gradually increased to 180° C. The temperature of the mixture was maintained at a temperature range of from 170° C. to 180° C. for 5 hours while stirring the mixture to react the compounds. After the reaction was terminated, the reaction product was cooled. Then the reaction product was filtered to obtain the precipitate. Then the precipitate was washed with chloroform until the precipitate colored blue. The cake was then washed with methanol several times, and further washed with hot water of 80° C. several times. Then the cake was dried. Thus, a rough titanyl phthalocyanine powder was obtained. The thus prepared rough titanyl phthalocyanine powder was added in concentrated sulfuric acid having a weight of 20 times the weight of the powder to dissolve the powder. The solution was dropped into iced water having a weight of 100 times the weight of the powder while stirring, to deposit a pigment. The mixture was filtered to obtain the crystal. The crystal was washed with water until the filtrate became neutral (pH of 7.0). Thus, a wet cake of a titanyl phthalocyanine pigment was prepared.
The position of a peak which was observed at a lowest Bragg (2θ) angle in the spectrum (hereinafter referred to as a lowest angle peak) was determined. In addition, a peak ratio of the peak intensity of a peak at a Bragg (2θ) angle of 28.6° to the peak intensity of a peak at a Bragg (2θ) angle of 27.2° was determined. Before the peak ratio was determined, the base line was corrected.
The ratio of the peak intensity observed for a peak at 28.6±0.2° to the maximum diffraction peak at 27.2±0.2° is less than 0.2 for the titanyl phthalocyanine crystal of the invention.
At this point, errors of ±0.2° are introduced with respect to the angles in the synthesis and measurements.
P1(28.6°)/
peak (°)
PI(27.2°)*
*Peak ratio (%) = {(Peak intensity of the peak at 28.6°)/(Peak intensity of the peak at 27.2°)} × 100
A TiOPc crystal was prepared by the method disclosed in Japanese Laid-Open Patent Publication No. 1-299874, which is as follows:
A TiOPc crystal was prepared by the method disclosed in Japanese Laid-Open Patent Publication No. 3-269064, which is as follows:
The wet cake of the titanyl phthalocyanine pigment prepared in Synthesis Example 1 was dried. One gram of the dried pigment was added in a mixture solvent of 100 g of a deionized water and 1 g of monochlorobenzene. The mixture was stirred for 1 hour at 50° C. After this operation, the pigment was washed with methanol and then washed with deionized water. The washed pigment was dried.
A TiOPc crystal was prepared by the method disclosed in Japanese Laid-Open Patent Publication No. 2-8256, which is as follows:
In a container, 9.8 grams of phthalodinitrile and 75 ml of 1-chloronaphthalene were contained and mixed while stirring. Under a nitrogen current, 2.2 ml of titanium tetrachloride were dropped therein. After titanium tetrachloride was added, the temperature of the mixture was gradually increased to 200° C. The temperature of the mixture was maintained at a temperature range of from 200° C. to 220 for 3 hours while stirring the mixture to react the compounds. After the reaction was terminated, the reaction product was cooled. When the reaction product was cooled to 130° C., the reaction product was filtered to obtain the precipitate. Then the precipitate was washed with 1-chloronaphthalene until the precipitate colored blue. The precipitate was then washed with methanol several times, and further washed with hot water of 80° C. several times.
A TiOPc crystal was prepared by the method disclosed in Japanese Laid-Open Patent Publication No. 64-17066, which is as follows:
Five (5) grams of α-type TiOPc, 10 g of sodium chloride, and 5 g of poyethyleneglycol were mixed and subjected to a crystal changing treatment at 100° C. for 10 hours using a sand grinder. The crystal was washed with deionized water and then with methanol. The crystal was refined using a dilute sulfuric acid, and then washed with deionized water until there was no sulfuric acid therein. Then the crystal was dried to prepare a comparative TiOPc crystal.
A TiOPc crystal was prepared by the method disclosed in Japanese Patent No. 2782765 (i.e., Japanese Laid-Open patent Publication No. 2-28265), which is as follows:
In a container, 20.4 parts of o-phthalodinitrile, 7.6 parts of titanium tetrachloride and 50 parts of quinoline were contained. The mixture was heated at 20° C. for 2 hours to react the compounds. Then the solvent was removed by steam-distillation. Then the reaction product was refined with 2% hydrochloric acid and then with 2% sodium hydroxide. The reaction product was washed with methanol and then with N,N-dimethylformamide, and then dried. Thus, titanyl phthalocyanine (TiOPc) was prepared. Two (2) parts of the tus prepared titanyl phthalocyanine were gradually added to 40 parts of 98% sulfuric acid of 5° C. to be dissolved therein. The solution was stirred for 1 hour while the temperature was maintained to be not higher than 5° C. The solution was gradually added to 400 parts of ice water, which were stirred at a high speed, to precipitate a crystal. The crystal was obtained by filtering. The crystal was washed until there was no acid in the filtrate. The thus prepared wet cake was added to 100 parts of tetrahydrofuran and stirred for about 5 hours. The mixture was filtered, and the filter cake was washed with tetrahydrofuran and then dried. Thus a comparative titanyl phthalocyanine crystal was prepared.
(PI(28.6°)/Pi(27.2°))
angle peak (°)
observed at 7.6°)
A pigment which was prepared in the same way as described in Japanese Laid-Open Patent Publication No. 61-239248 was added to the crystal prepared in Synthesis Example 1 in an amount of 3% by weight, and then the mixture was mixed using a mortar. The X-ray diffraction spectrum thereof is shown in FIG. 11.
In FIG. 11, two peaks are observed at 7.3° and 7.5° at the low angle side. It can be understood that these two peaks are of the different compounds.
Since only a peak is observed at 7.5° at the low angle side of the spectrum shown in FIG. 12, the spectrum shown in FIG. 12 is clearly different from that in FIG. 11.
The following dispersions were prepared using the TiOPc crystals prepared in Synthesis Examples 1 to 6 and Comparative Synthesis Examples 1 to 9.
Examples 7 to 12 and Comparative Examples 10 to 18
The procedure for preparation of the dispersions in Examples 1 to 6 and Comparative Examples 1 to 9 was repeated except that methyl ethyl ketone was replaced with n-butyl acetate.
Comparative Examples 19 to 33
The procedure for preparation of the dispersions in Examples 1 to 6 and Comparative Examples 1 to 9 was repeated except that methyl ethyl ketone was replaced with butanol.
Examples 13 to 18 and Comparative Examples 34 to 42
Photoreceptors of the present invention and comparative photoreceptors were prepared using the dispersions prepared in Examples 1 to 6 and Comparative Examples 1 to 9.
A corona voltage of −5.6 kV was applied to a photoreceptor for 15 seconds to charge the photoreceptor. The surface potential (V15) of the photoreceptor was measured at a time when stopping the corona discharging. At a time 15 seconds after stopping the corona discharging, the photoreceptor was then exposed to light of 1 μW/cm2 whose wavelength was 780±10 nm. At this point, the surface potential (Vd15) of the photoreceptor was measured at a time just before the light irradiation.
The procedure for preparation of the photoreceptor in Example 13 was repeated except that the charge generation layer coating liquid was changed to the following.
Examples 21 to 26 and Comparative Examples 43 and 44
The following undercoat layer coating liquid was coated on eight electroformed nickel belts and then dried. Thus an undercoat layer having a thickness of 4 μm was formed on each of the nickel belts.
The procedure for preparation of the photoreceptor in Example 21 was repeated except that the charge transport material (a) in the charge transport layer coating liquid was replaced with a compound having the following formula (b).
The procedure for preparation of the photoreceptor in Example 21 was repeated except that the charge transport material (a) in the charge transport layer coating liquid was replaced with a compound having the following formula (c).
The procedure for preparation of the photoreceptor in Example 21 was repeated except that the charge transport material (a) in the charge transport layer coating liquid was replaced with a compound having the following formula (d).
The procedure for preparation of the photoreceptor in Example 21 was repeated except that the charge transport material (a) in the charge transport layer coating liquid was replaced with a compound having the following formula (e).
The procedure for preparation of the photoreceptor in Example 21 was repeated except that the charge transport material (a) in the charge transport layer coating liquid was replaced with a compound having the following formula (f).
Comparative Examples 45 to 50
Six photoreceptors were prepared by replacing the charge transport material (a) in the charge transport layer coating liquid in Examples 21 to 26 with the charge transport material having the following formula (g).
Comparative Examples 51 to 53
The procedure for preparation of the photoreceptor in Comparative Examples 40 to 42 was repeated except that the substrate was changed from the aluminum plate to nickel belt used in Example 21.
V · sec)
Example 32 and Comparative Examples 54 and 55
On three same aluminum cylinders, the following undercoat layer coating liquid was coated and then dried to form an undercoat layer having a thickness of 3.5 μm thereon.
The procedure for preparation of the photoreceptor in Example 32 was repeated except that the charge transport layer coating liquid was replaced with the following coating liquid.
On an aluminum cylinder, which had been subjected to an anodic oxidation treatment and then a sealing treatment, the following charge generation layer coating liquid and charge transport layer coating liquid were coated and then dried one by one in this order to prepare a charge generation layer of 0.2 μm and a charge transport layer of 20 μm.
The procedure for preparation of the photoreceptor in Example 35 was repeated except that the charge transport layer coating liquid was replaced with the following coating liquid.
The procedure for preparation of the photoreceptor in Example 35 was repeated except that the charge generation layer coating liquid was replaced with the following coating liquid.
Examples 41 to 46 and Comparative Examples 60 and 61
The following undercoat layer coating liquid was coated on eight same electroformed nickel belts and then dried. Thus an undercoat layer having a thickness of 4 μm was prepared on the respective nickel belt.
The procedure for preparation of the photoreceptors in Example 41 was repeated except that the charge transport polymer (q) in the charge transport layer coating liquid was replaced with a polymer having the following formula (r).
The procedure for preparation of the photoreceptors in Example 41 was repeated except that the charge transport polymer (q) in the charge transport layer coating liquid was replaced with a polymer having the following formula (s).
The mobility was measured when the field strength was 5×105 V/cm.
Examples 49 and Comparative Examples 62 and 63
The procedure for preparation of the photoreceptor in Example 49 was repeated except that the charge transport polymer in the charge transport layer coating liquid was replaced with a polymer having the following formula (u).
The procedure for preparation of the photoreceptor in Example 49 was repeated except that the charge transport layer coating liquid was replaced with the following coating liquid.
The procedure for preparation of the photoreceptor in Example 51 was repeated except that the charge transport polymer (w) in the charge transport layer coating liquid was replaced with a charge transport polymer having the following formula (x).
The procedure for preparation of the photoreceptor in Example 51 was repeated except that the charge transport polymer (w) in the charge transport layer coating liquid was replaced with a charge transport polymer having the following formula (y).
The procedure for preparation of the photoreceptor in Example 51 was repeated except that the charge generation layer coating liquid was replaced with the following layer coating liquid.
The procedure for preparation of the photoreceptor in Example 51 was repeated except that the charge generation layer coating liquid was replaced with the following coating liquid.
As can be understood from the above explanation, the photoreceptor of the present invention, which includes a TiOPc crystal having a specific X-ray diffraction spectrum as a charge generation material, and a charge transport layer including a low-molecular-weight charge transport material and an inactive polymer and having a mobility not less than 1×10−5 cm/V·sec, can maintain high photosensitivity and good charge properties even when repeatedly used for a long time.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS4734348 *Oct 17, 1986Mar 29, 1988Tetsumi SuzukiPhotosensitive member for electrophotography containing polyvinyl acetalUS4863822 *Mar 9, 1988Sep 5, 1989Ricoh Company Ltd.Electrophotographic photoconductor comprising charge generating and transport layers containing adjuvantsUS4994566 *Apr 17, 1989Feb 19, 1991Nec CorporationPhthalocyanine crystal, process for manufacture thereof and its use for electrophotographic photosensitive materialUS5028502 *Jan 29, 1990Jul 2, 1991Xerox CorporationHigh speed electrophotographic imaging systemUS5213929 *Jun 6, 1990May 25, 1993Nec CorporationTitanyl phthaloycyanine crystal, method of manufacture thereof and its use for electrophotographic photosensitive materialUS5215840 *Nov 15, 1991Jun 1, 1993Konica CorporationElectrophotographic photoreceptor and manufacturing method thereofUS5298353 *Mar 11, 1993Mar 29, 1994Canon Kabushiki KaishaElectrophotographic photosensitive memberUS5409792 *Oct 24, 1994Apr 25, 1995Xerox CorporationPhotoreceptor containing dissimilar charge transporting small molecule and charge transporting polymerUS5430526 *Mar 18, 1994Jul 4, 1995Canon Kabushiki KaishaImage forming apparatus having weighting material in image bearing member and process cartridge usable with sameUS5547790Oct 20, 1994Aug 20, 1996Ricoh Company, Ltd.Electrophotographic photoconductor containing polymeric charge transporting material in charge generating and transporting layersUS5595846 *Jun 20, 1995Jan 21, 1997Mitsubishi Chemical CorporationPhthalocyanine mixed crystal, production method thereof,and electrophotographic photoreceptorUS5618645 *Mar 17, 1995Apr 8, 1997Fuji Photo Film Co., Ltd.Electrophotographic printing plate precursorUS5677094Sep 28, 1995Oct 14, 1997Ricoh Company, Ltd.Electrophotographic photoconductorUS5804343Jan 24, 1996Sep 8, 1998Ricoh Company, Ltd.Electrophotographic photoconductorUS5804344 *Mar 11, 1997Sep 8, 1998Mitsubishi Chemical CorporationElectrophotographic photoreceptor containing an arylamine type compoundUS5853935Mar 12, 1998Dec 29, 1998Ricoh Company, Ltd.Electrophotographic photoconductorUS5871876May 23, 1997Feb 16, 1999Ricoh Company, Ltd.Electrophotographic photoconductorUS6087055Mar 4, 1998Jul 11, 2000Ricoh Company, Ltd.Electrophotographic photoconductorUS6132911Jul 22, 1999Oct 17, 2000Ricoh Company, Ltd.Method for manufacturing pigment, electrophotographic photoconductor using the pigment and electrophotographic image forming method and apparatus using the photoconductorUS6218533Jul 7, 2000Apr 17, 2001Ricoh Company, Ltd.Method for manufacturing pigment, electrophotographic photoconductor using the pigment and electrophotographic image forming method and apparatus using the photoconductorUS6284420 *Jan 26, 2000Sep 4, 2001Industrial Technology Research InstituteTitanyl phthalocyanine, method for production thereof and electrophotographic photoreceptor containing the sameUS6326112Aug 21, 2000Dec 4, 2001Ricoh Company LimitedElectrophotographic photoreceptor, and process cartridge and image forming apparatus using the photoreceptorUS7029810 *Sep 22, 2003Apr 18, 2006Ricoh Company, Ltd.Electrophotographic image forming apparatusEP0384470A2 *Feb 22, 1990Aug 29, 1990Mitsubishi Chemical CorporationProcess for preparation of crystalline oxytitanium phthalocyanineJPH0228265A * Title not availableJPH11140337A * Title not available* Cited by examinerNon-Patent CitationsReference1 *Derwent Abstract Acc. No. 1989-302238 describing JP 02-028265, published Jan. 31, 2000.2 *Diamond, A.S., ed., Handbook of Imaging Materials, Marcel Dekker, Inc., NY (1991), pp. 396-397.3Fujimaki, et al., "High Photosensitivity of an Organic Photoreceptor", IS&T's Seventh International Congress on Advances in Non-Impact Printing Technologies, Oct. 6-11, 1991, vol. One, pp. 269-275.4Fujimaki, et al., "High Photosensitivity of an Organic Photreceptor", IS&T's Seventh International Congress on Advances in Non-Impact Printing Technologies, Oct. 6-11, 1991, vol. One, pp. 269-275.5 *Japanese Patent Office English-Language Translation of JP 11-140337 (Pub. May 1999).6 *Ladd, M.F.C. et al, Structure Determination by X-Ray Crystallography, Plenum Press, NY (1985), pp. 424-426.7Patent Abstracts of Japan; Publication No. 01017066 A; Publication Date Jan. 20, 1989; Fujimaki Yoshihide, et al.; Filed Jul. 10, 1987; Application No. 62173640.8Patent Abstracts of Japan; Publication No. 01299874 A; Publication Date Dec. 4, 1989; Enokida Toshio; Filed May 26, 1988; Application No. 63129327.9Patent Abstracts of Japan; Publication No. 02008256 A; Publication Date Jan. 11, 1990; Suzuki Tetsuyoshi, et al. Filed Nov. 5, 1988; Application No. 63279663.10Patent Abstracts of Japan; Publication No. 02028265 A; Publication Date Jan. 30, 1990; Mimura Yoshikazu, et al.; Filed Mar. 15, 1989; Application No. 01064801.11Patent Abstracts of Japan; Publication No. 03035064 A; Publication Date Feb. 15, 1991; Kinoshita Akira, et al.; Filed Jun. 30, 1989; Application No. 01170355.12Patent Abstracts of Japan; Publication No. 03035245 A, Publication Date Feb. 15, 1991; Kinoshita Akira, et al.; Filed Jun. 30, 1989; Application No. 01170360.13Patent Abstracts of Japan; Publication No. 03037669 A, Publication Date Feb. 19, 1991; Oda Yasuhiro, et al.; Filed Jul. 4, 1989; Application No. 01173733.14Patent Abstracts of Japan; Publication No. 03269064 A; Publication Date Nov. 29, 1991; Tokia Akihiko, et al.; Filed Mar. 20, 1990; Application No. 02068089.15Patent Abstracts of Japan; Publication No. 07319179 A; Publication Date Dec. 8, 1995; Yamazaki Kazuo, et al.; Filed May 27, 1994; Application No. 06136636.16Patent Abstracts of Japan; Publication No. 57148745 A; Publication Date Sep. 14, 1982; Hiratsuka Hiroaki, et al.; Filed Mar. 11, 1981; Application No. 56033977.17Patent Abstracts of Japan; Publication No. 59031965 A; Publication Date Feb. 21, 1984; Nakarai Toyoaki, et al.; Filed Aug. 16, 1982; Application No. 57142458.18Patent Abstracts of Japan; Publication No. 59036254 A; Publication Date Feb. 28, 1984; Nakarai Toyoaki, et al.; Filed Aug. 23, 1982; Application No. 57146538.19Patent Abstracts of Japan; Publication No. 59044054 A; Publication Date Mar. 12, 1984; Nishioka Yoichi, et al.; Filed Sep. 6, 1982;Application No. 57153982.20Patent Abstracts of Japan; Publication No. 59049544 A; Publication Date Mar. 22, 1984; Nogami Sumitaka, et al.; Filed Sep. 16, 1982; Application No. 57159469.21Patent Abstracts of Japan; Publication No. 59166959 A; Publication Date Sep. 20, 1984; Matsuura Taketoshi, et al.; Filed Mar. 14, 1983; Application No. 58040798.22Patent Abstracts of Japan; Publication No. 61239248 A; Publication Date Oct. 24, 1986; Oaku Kenichi, et al.; Filed Apr. 16, 1985; Application No. 60079240.23Patent Abstracts of Japan; Publication No. 62067094 A; Publication Date Mar. 26, 1987; Suzuki Tetsuyoshi, et al.; Filed Sep. 18, 1985; Application No. 60205541.24Patent Abstracts of Japan; Publication No. 63000366 A; Publication Date Jan. 5, 1988; Takagishi Iwao; Filed Jun. 19, 1986; Application No. 61143445.25Patent Abstracts of Japan; Publication No. 63116158 A; Publication Date May 20, 1988; Enokida Toshio, et al. Filed Nov. 5, 1987; Application No. 61262030.26Patent Abstracts of Japan; Publication No. 63196067 A; Publication Date Aug. 15, 1988; Taguchi Kenji, et al. Filed Feb. 10, 1987; Application No. 62027155.27Pending U.S. Appl. No. 09/796,470, filed Mar. 2, 2001.28Pending U.S. Appl. No. 09/903,718, filed Jul. 13, 2001.29Pending U.S. Appl. No. 09/985,347, filed Nov. 2, 2001.30Pending U.S. Appl. No. 09/985,348, filed Nov. 2, 2001.31Pending U.S. Appl. No. 09/985,368, filed Nov. 2, 2001.32Pending U.S. Appl. No. 09/985,375, filed Nov. 2, 2001.33Pending U.S. Appl. No. 10/020,925, filed Dec. 19, 2001.34Pending U.S. Appl. No. 10/205,413, filed Jul. 26, 2002.35U.S. Appl. No. 09/734,718, filed Dec. 13, 2000.36U.S. Appl. No. 09/817,151, filed Mar. 27, 2001.37U.S. Appl. No. 09/942,574, filed Aug. 31, 2001.38U.S. Appl. No. 10/665,155, filed Sep. 22, 2003, Toda et al.39U.S. Appl. No. 10/804,067, filed Mar. 19, 2004, Toda et al.40U.S. Appl. No. 10/927,050, filed Aug. 27, 2004, Niimi et al.41U.S. Appl. No. 10/944,614, filed Sep. 20, 2004, Niimi et al.42U.S. Appl. No. 11/219,886, filed Sep. 7, 2005, Niimi et al.43U.S. Appl. No. 11/332,545, filed Jan. 17, 2006, Tamoto et al.44U.S. Appl. No. 11/364,325, filed Mar. 1, 2006, Niimi.45U.S. Appl. No. 11/367,786, filed Mar. 6, 2006, Ohta et al.46U.S. Appl. No. 11/474,258, filed Jun. 26, 2006, Niimi.47 *US Patent & Trademark Office English-Language Translation of JP 11-140337 (pub. May 25, 1999).* Cited by examinerReferenced byCiting PatentFiling datePublication dateApplicantTitleUS7371497 *Nov 2, 2005May 13, 2008Ricoh Company Ltd.Electrophotographic image forming methodUS7419751 *Jun 5, 2003Sep 2, 2008Ricoh Company, Ltd.Titanylphthalocyanine crystal and method of producing the titanylphthalocyanine crystal, and electrophotographic photoreceptor, method, apparatus and process cartridge using the titanylphthalocyanine crystalUS7894750May 16, 2007Feb 22, 2011Ricoh Company LimitedCompact and high speed image forming apparatus and image forming method using the sameUS8380109Jan 9, 2009Feb 19, 2013Ricoh Company, Ltd.Image forming apparatus and process cartridgeUS8802337 *Nov 8, 2012Aug 12, 2014Fuji Xerox Co., Ltd.Electrophotographic photoreceptor, image forming apparatus, and process cartridgeUS20040033428 *Jun 5, 2003Feb 19, 2004Tatsuya NiimiTitanylphthalocyanine crystal and method of producing the titanylphthalocyanine crystal, and electrophotographic photoreceptor, method, apparatus and process cartridge using the titanylphthalocyanine crystalUS20060105255 *Nov 2, 2005May 18, 2006Naohiro TodaElectrophotographic image forming apparatusUS20070268354 *May 16, 2007Nov 22, 2007Yoshinori InabaImage forming apparatus and image forming methodUS20080286008 *Jul 16, 2008Nov 20, 2008Tatsuya NiimiTitanylphthalocyanine crystal and method of producing the titanylphthalocyanine crystal, and electrophotographic photoreceptor, method, apparatus and process cartridge using the titanylphthalocyanine crystal* Cited by examinerClassifications U.S. Classification430/78, 430/59.5, 540/140, 540/141, 430/96International ClassificationG03G5/06, C09B47/08, C09B47/04Cooperative ClassificationC09B47/073, G03G5/0542, C09B67/0026, G03G5/0696European ClassificationC09B47/073, C09B67/00C2, G03G5/06H6, G03G5/05C2DLegal EventsDateCodeEventDescriptionMay 8, 2000ASAssignmentOwner name: RICOH COMPANY, LTD., JAPANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:NIIMI, TATSUYA;SUZUKI, TETSURO;REEL/FRAME:010786/0393Effective date: 20000427Sep 2, 2010FPAYFee paymentYear of fee payment: 4Aug 28, 2014FPAYFee paymentYear of fee payment: 8RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services