JP4887716B2 - Oxytitanium phthalocyanine composition, electrophotographic photoreceptor, and image forming apparatus using the photoreceptor - Google Patents

Description

  The present invention relates to an oxytitanium phthalocyanine compound suitable for an electrophotographic photosensitive member, an electrophotographic photosensitive member using the oxytitanium phthalocyanine compound, and an image forming apparatus using the electrophotographic photosensitive member. The present invention relates to an oxytitanium phthalocyanine compound having excellent residual potential, an electrophotographic photosensitive member using the same, and an image forming apparatus using the electrophotographic photosensitive member.

  Phthalocyanines having photoconductive properties with high sensitivity to long-wavelength light have been extensively studied as excellent photoconductive materials. In particular, it can be suitably used for electrophotographic photoreceptors, electrophotographic plate making materials, photoelectric conversion materials such as image sensors, and is used as a charge generation material for electrophotographic photoreceptors for long-wavelength semiconductor lasers and light-emitting diodes. ing.

  Phthalocyanines are known not only to have different physical properties such as absorption spectrum and photoconductivity depending on the type of central metal, but also to vary greatly depending on the crystal form. Among phthalocyanines, oxytitanium phthalocyanine is particularly Various crystal types having high photoconductive properties are known. Among them, in the powder X-ray diffraction spectrum with respect to CuKα characteristic X-ray, a so-called D-type crystalline oxytitanium phthalocyanine having a clear peak in the vicinity of a Bragg angle (2θ ± 0.2 °) of 27.3 ° is It is known that the sensitivity is particularly excellent (see, for example, Patent Document 1).

  The thin film X-ray diffraction spectrum by CuKα characteristic X-ray of the photosensitive layer containing D-type oxytitanium phthalocyanine has at least one strong Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.8 °. It has at least a diffraction peak and a diffraction peak strong at 27.3 °, and the peak intensity of the maximum peak between 9.0 ° and 9.8 ° is larger than the peak intensity of 27.3 °, and in the spectrum It is known that the maximum diffraction peak is shown in all the diffraction peaks (see, for example, Patent Document 2).

Oxytitanium phthalocyanine is generally partially chlorinated in order to react phthalonitrile or 1,3-diiminoisoindoline with titanium chloride such as titanium tetrachloride at a high temperature of 180 ° C. or higher in a high boiling point solvent. Accompanying the reaction, the chlorine content results in containing chlorinated oxytitanium phthalocyanine. Oxytitanium phthalocyanine having a mass spectrum of 0.015-0.055 in proportion to chlorinated oxytitanium phthalocyanine relative to unsubstituted oxytitanium phthalocyanine is said to have good sensitivity and residual potential (eg, patents) See reference 3.)
Japanese Patent Laid-Open No. 2-8256 Japanese Patent No. 2881922 Japanese Patent Laid-Open No. 2001-115054

  Oxytitanium phthalocyanine having various crystal structures described above is useful as a charge generating material for an electrophotographic photoreceptor, and in particular, a Bragg angle (2θ ±) in a powder X-ray diffraction spectrum generally called D-type. It is known that oxytitanium phthalocyanine having a crystal structure having a clear diffraction peak in the vicinity of 27.3 ° provides a photoconductor that is particularly excellent in sensitivity when used in the photoconductive layer of an electrophotographic photoconductor. However, there has been a case in which the requirement cannot be fully satisfied in the recent demand for improvement in characteristics required of the photosensitive member in order to increase the image forming speed.

  An object of the present invention is to provide an oxytitanium phthalocyanine composition suitable as a photoelectric material, an electrophotographic photosensitive member having a high sensitivity and a low residual potential, and an image forming apparatus using the photosensitive member.

  In the oxytitanium phthalocyanine composition, the present inventors show a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in a powder X-ray diffraction spectrum. As a result of diligent investigation focusing on the content, when the ratio of chlorinated oxytitanium phthalocyanine is within a specific range in terms of mass spectral intensity ratio relative to unsubstituted oxytitanium phthalocyanine, it has excellent crystal form controllability, and It has been found that an electrophotographic photoreceptor using this is particularly excellent in sensitivity and residual potential. Then, by using phthalonitrile and titanium halide as raw materials and using a diarylalkane as a reaction solvent, it was found that production can be performed with good reproducibility, and the present invention has been completed.

  Further, the present inventors have further found that the powder X-ray diffraction spectrum of oxytitanium phthalocyanines and the thin film X-ray diffraction spectrum of the photosensitive layer containing the phthalocyanines may have different intensity ratios, The present inventors have found that a thin film X-ray diffraction spectrum with respect to CuKα characteristic X-rays of the photosensitive layer shows a high sensitivity and a low residual potential when having a specific intensity ratio, thereby completing the present invention.

  That is, the first gist of the present invention is an oxytitanium characterized by showing a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray. A phthalocyanine composition, wherein the ratio of chlorinated oxytitanium phthalocyanine in the composition is 0.015 to 0.070 in terms of mass spectral intensity ratio to unsubstituted oxytitanium phthalocyanine Lies in the phthalocyanine composition.

The second gist of the present invention is an electrophotographic photosensitive member having a photosensitive layer containing the oxytitanium phthalocyanine composition according to the present invention on a conductive support, which is based on the CuKα characteristic X-ray of the photosensitive layer. The thin film X-ray diffraction spectrum has at least one strong diffraction peak at a Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.8 °, and a strong diffraction peak at 27.3 °; and The peak intensity at 27.3 ° is at least 10% larger than the peak intensity of the maximum peak at 9.0 ° to 9.8 °, and the peak intensity at 27.3 ° is the maximum diffraction peak among all diffraction peaks. An electrophotographic photoreceptor characterized by the above.

The third gist of the present invention is an electrophotographic photosensitive member having a photosensitive layer containing the oxytitanium phthalocyanine composition according to the present invention on a conductive support, and the CuKα characteristic X of the photosensitive layer. The thin film X-ray diffraction spectrum by a line has at least one strong diffraction peak at Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.8 ° and a strong diffraction peak at 27.3 ° In addition, the peak intensity at 27.3 ° after correcting the baseline is 25% or more larger than the peak intensity after correcting the baseline of the maximum peak in the range of 9.0 ° to 9.8 °. The electrophotographic photosensitive member is characterized in that the peak intensity of 3 ° is the maximum diffraction peak among all diffraction peaks.

  Furthermore, a fourth aspect of the present invention resides in an image forming apparatus using the electrophotographic photosensitive member of the present invention.

  An oxytitanium phthalocyanine composition having a powder X-ray diffraction spectrum specific to the present invention and a specific proportion of chlorinated oxytitanium phthalocyanine has a particularly high sensitivity and residual potential by incorporating the composition into a photosensitive layer. Can be provided. In addition, an electrophotographic photosensitive member having a photosensitive layer exhibiting a thin film X-ray diffraction spectrum having a specific peak intensity ratio according to the present invention can provide an electrophotographic photosensitive member having a particularly high sensitivity and a low residual potential compared to the conventional one. It is possible to provide an image forming apparatus with high performance.

  Hereinafter, embodiments of the present invention will be described in detail. However, the description of the constituent elements described below is a representative example of the embodiments of the present invention, and is appropriately modified and implemented without departing from the spirit of the present invention. can do.

  The oxytitanium phthalocyanine composition of the present invention has a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray, It is a composition containing titanium phthalocyanine, but contains various oxytitanium phthalocyanine derivatives substituted with a substituent such as a fluorine atom, a nitro group, a cyano group or a sulfone group in addition to chlorinated oxytitanium phthalocyanine. It doesn't matter.

  In the oxytitanium phthalocyanine composition of the present invention, the ratio of the chlorinated oxytitanium phthalocyanine represented by the following formula (1) is compared with the unsubstituted oxytitanium phthalocyanine represented by the following formula (2). 0.015 to 0.070. The mass spectrum intensity ratio is preferably 0.020 or more, more preferably 0.025 or more, and the mass spectrum intensity ratio is preferably 0.060 or less, more preferably 0.055 or less. is there.

  If the mass spectral intensity ratio is too small, there is a risk of mixing a crystal form different from the target crystal form of the present invention when producing an oxytitanium phthalocyanine composition. In such a case, the oxytitanium When the phthalocyanine composition is used for an electrophotographic photoreceptor, the sensitivity may be lowered. In addition, if the intensity ratio of the mass spectrum is too large, the crystal form growth of the oxytitanium phthalocyanine composition intermediate proceeds and it becomes difficult to make the intermediate amorphous, so that it can be made into a suitable crystal form as a photoelectric material. For example, when used for an electrophotographic photosensitive member, an electrophotographic photosensitive member with high sensitivity cannot be obtained.

<Spectral intensity ratio>
The spectral intensity ratio of chlorinated oxytitanium phthalocyanine to unsubstituted oxytitanium phthalocyanine by mass spectrum can be measured, for example, by the following method.

・ Adjustment of sample for measurement;
Place 0.50 g of oxytitanium phthalocyanine composition, 30 g of glass beads (particle size: φ1.0 to 1.4 mm), and 10 g of cyclohexanone in a 50 ml glass container, shake with a paint shaker for 3 hours, and add oxytitanium phthalocyanine dispersion. Make it.

  1 μl of this dispersion was collected in a 10 ml sample bottle, 5 ml of chloroform was added, and the mixture was dispersed for 1 hour at room temperature using an ultrasonic oscillator to prepare a 10 ppm dispersion for measurement.

-Measuring equipment and measuring conditions;
As a mass spectrum measuring apparatus, JMS-700 manufactured by JEOL is used, ionization mode: DCI (−), reaction gas: isobutane (ionization chamber pressure 1 × 10 ⁻⁵ Torr), temperature rising condition: 0 → 0.95 A (1 A / min), accelerating voltage: 8.0 KV, mass spectrometric capability: 2000, scanning method: MF-Linear, scanning mass range: 500-680, full mass range scanning time: 0.8 seconds, repetition time: 0. Measurement was performed under measurement conditions of 5 seconds (scanning time 0.05 seconds, waiting time 0.45 seconds).

・ Strength ratio of chlorinated oxytitanium phthalocyanine;
1 μl of the measurement dispersion was applied to a filament of a DCI probe, and mass spectrum measurement was performed under the above conditions. In the obtained mass spectrum, the peak area obtained from ion chromatography of m / z: 610 corresponding to the molecular ion of chlorinated oxytitanium phthalocyanine and m / z: 576 corresponding to the molecular ion of unsubstituted oxytitanium phthalocyanine ([610] peak area / [576] peak area) is calculated as the spectral intensity ratio.

<Production of oxytitanium phthalocyanine composition>
The oxytitanium phthalocyanine composition according to the present invention is obtained by synthesizing, for example, dichlorotitanium phthalocyanine using phthalonitrile and titanium halide as raw materials, and then hydrolyzing and purifying the dichlorotitanium phthalocyanine composition. And an amorphous oxytitanium phthalocyanine composition obtained by amorphizing the resulting oxytitanium phthalocyanine composition intermediate can be produced by crystallization in a solvent.

  More specifically, for example, dichlorotitanium phthalocyanine is obtained by a known method such as heating and reacting phthalonitrile and titanium halide in the presence of a high-boiling organic solvent. As the high boiling point solvent at this time, any solvent can be used as long as it has a boiling point higher than the temperature at the time of reaction without reacting with the raw materials and products, but finally obtained. In order to control the content of chlorinated oxytitanium phthalocyanine contained in oxytitanium phthalocyanine, a non-halogenated solvent is preferable, and it is a non-halogen compound such as diphenylmethane, diphenylethane, diphenyl ether, sulfolane and has a cyclic structure. A solvent having an aromatic ring such as diphenylmethane, diphenylethane, and diphenyl ether is more preferably used. Particularly preferably, a diarylalkane solvent having a structure in which a phenyl group is connected by an alkylidene group, such as diphenylmethane and diphenylethane, is used.

  Titanium chloride is preferred as the titanium halide. Examples of titanium chloride include titanium tetrachloride, titanium trichloride, and the like, and titanium tetrachloride is particularly preferable. When titanium tetrachloride is used, the content of chlorinated oxytitanium phthalocyanine contained in the obtained oxytitanium phthalocyanine composition can be easily controlled.

  The reaction temperature is usually 150 ° C. or higher, preferably 180 ° C. or higher. In order to control the content of chlorinated oxytitanium phthalocyanine, more preferably 190 ° C. or higher, usually 300 ° C. or lower, preferably 250 ° C. or lower, more Preferably it is performed at 230 degrees C or less. Usually, titanium chloride is added to a mixture of phthalonitrile and a reaction solvent. The titanium chloride at this time may be added directly as long as it has a boiling point or less, or may be added in combination with the high boiling point solvent. Addition at a temperature higher than the boiling point is performed by mixing with the high boiling point solvent. Part of the titanium chloride is preferably added at a temperature of the mixture of 160 ° C. or lower, more preferably 120 ° C. or lower, and even more preferably 100 ° C. or lower. If the temperature at the time of addition is too high, the content of chlorinated oxytitanium phthalocyanine decreases.

  For example, when dioxyalkane is used as a reaction solvent and oxytitanium phthalocyanine is produced using phthalonitrile and titanium tetrachloride, titanium tetrachloride is added separately at a low temperature of 100 ° C. or lower and a high temperature of 180 ° C. or higher. The ratio of chlorinated oxytitanium phthalocyanine to unsubstituted oxytitanium phthalocyanine can be controlled to the ratio of the present invention.

  The temperature raising time for reaching the reaction temperature is preferably 0.5 to 4 hours, more preferably 0.5 to 3 hours, and the reaction duration is preferably 1 to 10 hours, more preferably 2 to 2 hours. 8 hours, more preferably 2 to 6 hours. This is for controlling the content of chlorinated oxytitanium phthalocyanine in the oxytitanium phthalocyanine composition.

  The obtained dichlorotitanium phthalocyanine is heated and hydrolyzed with alcohols having a boiling point of 100 ° C. or higher such as butanol, pentanol, hexanol, octanol, cyclohexanol, or ketones such as acetophenone, cyclohexanone, hexanedione, and the like. The intermediate is a titanium phthalocyanine composition. In this case, various crystal forms of the oxytitanium phthalocyanine composition intermediate are used. Usually, in a powder X-ray diffraction spectrum by CuKα characteristic X-ray, a Bragg angle (2θ ± 0.2 °) of 7.6 is used. It has a strong diffraction peak at °, 25.5 °, and 28.6 °, and is usually called B-type. However, since the B-type oxytitanium phthalocyanine often coexists with other crystal types of phthalocyanines, it is repeatedly hydrolyzed until no other crystal type peak is substantially observed in the powder X-ray diffraction spectrum. Preferably it is done. If other crystal forms of phthalocyanines remain, it will be a major factor in reducing the sensitivity.

  The obtained oxytitanium phthalocyanine composition intermediate is pulverized by a known mechanical pulverizer such as a paint shaker, ball mill, sand grind mill, or so-called acid paste method for obtaining a solid in cold water after being dissolved in concentrated sulfuric acid, etc. To make it amorphous.

  The obtained amorphous oxytitanium phthalocyanine composition is crystallized with a known solvent to obtain the oxytitanium phthalocyanine composition according to the present invention. More specifically, orthodichlorobenzene, chlorobenzene, and chloronaphthalene are obtained. Halogenated aromatic hydrocarbon solvents such as: halogenated hydrocarbon solvents such as chloroform and dichloroethane; aromatic hydrocarbon solvents such as methylnaphthalene, toluene and xylene; ethyl acetate, butyl acetate and methyl ethyl ketone are preferably used; Of these, orthodichlorobenzene, toluene, methylnaphthalene, and ethyl acetate are preferable.

<X-ray diffraction spectrum>
The powder X-ray diffraction spectrum by CuKα characteristic X-ray of the oxytitanium phthalocyanine composition can be measured according to a method usually used for powder X-ray diffraction measurement of a solid. The oxytitanium phthalocyanine composition of the present invention has a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray. Among these, the Bragg angle ( (2θ ± 0.2 °) 26.3 ° preferably does not have a strong diffraction peak.

  On the other hand, the photosensitive layer of the electrophotographic photoreceptor according to the present invention has a thin film X-ray diffraction spectrum by CuKα characteristic X-ray of at least one at a Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.8 °. It has at least a strong diffraction peak and a strong diffraction peak at 27.3 °. The peak intensity at 27.3 ° is 10% or more larger than the peak intensity of the maximum peak at 9.0 ° to 9.8 °, and the peak intensity at 27.3 ° is the maximum diffraction among all diffraction peaks. The peak intensity at 27.3 ° after correction of the baseline is 25% or more than the peak intensity after correction of the baseline of the maximum peak between 9.0 ° and 9.8 °. The peak intensity of 27.3 °, which is large, is the largest diffraction peak among all diffraction peaks.

  Various states can be considered for the presence of the oxytitanium phthalocyanine composition in the photosensitive layer, but the thin film X-ray diffraction spectrum for CuKα characteristic X-rays of the photosensitive layer has a Bragg angle (2θ ± 0.2 °) of 9.0. At least one strong diffraction peak from ° to 9.8 °, and a strong diffraction peak at 27.3 °, and a peak intensity of 27.3 ° is the maximum among 9.0 ° to 9.8 ° The peak intensity after the peak intensity of 27.3 ° is 10% or more larger than the peak intensity of the peak, or the peak intensity at 27.3 ° after correcting the baseline is corrected to the baseline of the maximum peak from 9.0 ° to 9.8 ° As long as it is larger than 25%, any form may be used.

  The peak intensity of the Bragg angle (2θ ± 0.2 °) of 27.3 ° in the thin film X-ray diffraction spectrum with respect to the CuKα characteristic X-ray of the photosensitive layer is the peak of the maximum peak from 9.0 ° to 9.8 °. It is preferably greater than 115% of the strength, more preferably greater than 125%, and even more preferably greater than 130%. This is because the sensitivity becomes higher. However, if it is too large, there may be a problem in dispersion, so that the peak intensity at 27.3 ° is smaller than 300% of the peak intensity of the maximum peak at 9.0 ° to 9.8 °. Preferably, it is less than 250%, more preferably less than 200%.

  The thin film X-ray diffraction spectrum by the CuKα characteristic X-ray of the photosensitive layer may be measured by any method as long as it can obtain the thin film X-ray diffraction spectrum of the photosensitive layer itself. And a method of forming a photosensitive layer on a glass surface and measuring it. More specifically, an example of a method for measuring a thin film X-ray diffraction spectrum by CuKα characteristic X-rays of the photosensitive layer is shown below.

1. Sample preparation method;
A coating solution for forming a photosensitive layer is applied to an antireflective cover glass so that the film thickness after drying is 10 μm or more, and is dried.

2. Measuring equipment and measuring conditions;
In order to measure the diffraction spectrum, a diffractometer for a thin film sample (Rigaku RINT2000) using CuKα rays monochromatically parallelized by an artificial multilayer film mirror as a radiation source was used as a measuring apparatus. Measurement conditions are: X-ray output 50 kV, 250 mA, fixed incident angle (θ) 1.0 °, scanning range (2θ) 3-40 °, scan step width 0.05 °, incident solar slit 5.0 °, incident slit The diffraction spectrum was measured at 0.1 mm and a light receiving solar slit of 0.1 °.

3. About peak intensity;
The peak intensity represents the height of the peak on the chart of the obtained spectrum, and the correction of the baseline is 7.3 ° or more for the maximum peak in the range of 9.0 ° to 9.8 °. 8. Connect the point with the lowest diffraction intensity in the range below the Bragg angle of the maximum peak and the point with the lowest diffraction intensity in the range of 11.4 ° or less above the Bragg angle of the maximum peak, and use that as the baseline. The maximum peak intensity in the range of 0 ° to 9.8 ° is calculated. In the case of the peak at 27.3 °, the point with the lowest diffraction intensity in the range of 24.1 ° to 27.3 ° and the point with the lowest diffraction intensity in the range of 27.3 ° to 28.6 ° And the peak intensity at 27.3 ° is calculated using this as the baseline.

  In a powder X-ray diffraction spectrum by CuKα characteristic X-ray by a conventionally known technique, an oxytitanium phthalocyanine (so-called D-type) crystal having a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° is: The powder X-ray diffraction spectrum has a diffraction angle and peak intensity ratio similar to those of the oxytitanium phthalocyanine composition of the present invention. In the photosensitive layer containing the phthalocyanine crystal, the thin film X-ray diffraction spectrum by CuKα characteristic X-ray It is known that the peak in the Bragg angle (2θ ± 0.2 °) 9.0 ° to 9.8 ° is the maximum intensity, which is different from the photosensitive layer of the electrophotographic photosensitive member of the present invention. is there.

  According to the crystal structure analysis of oxytitanium phthalocyanine, in the powder X-ray diffraction spectrum by CuKα characteristic X-ray, the peak of Bragg angle (2θ ± 0.2 °) 27.3 ° is that of oxytitanium phthalocyanine overlapping in the c-axis direction. The stacking distance is indicated, and it is suggested that the larger the intensity ratio, the higher the c-axis orientation. Therefore, it can be estimated that so-called D-type oxytitanium phthalocyanine is a crystal having c-axis orientation. However, when dispersed in the photosensitive layer, the peak at 9.0 ° to 9.8 ° becomes the maximum peak in the thin film X-ray diffraction spectrum by CuKα characteristic X-ray, and isotropic arrangement in the photosensitive layer. Indicates. In contrast, the oxytitanium phthalocyanine of the present invention has a maximum peak of 27.3 ° in the thin film X-ray diffraction spectrum by CuKα characteristic X-rays even after being dispersed in the photosensitive layer. The c-axis orientation is maintained even after treatment. Therefore, it is considered that the sensitivity is higher than that of conventional phthalocyanine.

<Electrophotographic photoreceptor>
The photosensitive layer of the electrophotographic photosensitive member of the present invention may have a single layer structure (hereinafter sometimes referred to as a single layer type photosensitive member) in which a charge generating substance, a charge transporting substance and a binder resin are contained in a single layer. Alternatively, a stacked structure in which a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material are stacked (hereinafter sometimes referred to as a multilayer photoreceptor) may be used. The photosensitive layer is composed of the oxytitanium phthalocyanine composition according to the present invention together with other raw materials such as a charge generation material, a charge transport material, a binder resin, and a solvent, as well as a sand grind mill, a ball mill, an attritor, and an ultrasonic oscillation device. It can be formed by applying a coating solution for coating a photosensitive layer obtained by a known dispersion method such as dispersing with a dispersing machine such as a coating on a conductive support and drying. In particular, the photosensitive layer is obtained by applying the coating liquid obtained by treating a liquid containing oxytitanium phthalocyanine and a binder resin with a sand grind mill and / or an ultrasonic oscillator on a conductive support and drying it. Is preferably formed.

  In the photosensitive layer of the electrophotographic photosensitive member of the present invention, other known charge generating materials different from the oxytitanium phthalocyanine composition according to the present invention may be used in combination. Examples of the charge generating substance used in combination include various photoconductive materials such as a phthalocyanine pigment, an azo pigment, a quinacridone pigment, an indigo pigment, a perylene pigment, a polycyclic quinone pigment, an anthrone pigment, a benzimidazole pigment, and a squalium pigment.

  As binder resin for binding the photosensitive layer, polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, vinyl alcohol, ethyl vinyl ether, polyvinyl acetal resin, polycarbonate resin , Polyamide resin, cellulose ether resin, polyurethane resin, polyester resin, polyester polycarbonate resin, polyarylate resin, phenoxy resin, silicon resin, epoxy resin and the like. As the binder resin, only one kind of these resins may be used, or a mixture of two or more kinds may be used. In the case of a single layer type photoreceptor, among these resins, polycarbonate resin, polyester resin, polyester polycarbonate resin, and polyarylate resin are preferably used. In the case of a laminate type photoreceptor, among these resins, polyvinyl acetal Resin and phenoxy resin are preferably used.

  Solvents used in the coating solution for forming the photosensitive layer include alcohols such as methanol, ethanol and propanol, ethers such as tetrahydrofuran, 1,4-dioxane and 1,2-dimethoxyethane, methyl ethyl ketone, cyclohexanone and 4-methoxy. Examples include ketones such as -4-methyl-2-pentanone and hydrocarbons such as toluene. Only one of these solvents may be used, or a mixture of two or more may be used. Among these solvents, 1,2-dimethoxyethane and 4-methoxy-4-methyl-2-pentanone are preferable. This is because the crystal stability of the oxytitanium phthalocyanine composition of the present invention is enhanced.

  The ratio between the charge generating material and the binder resin is not particularly limited, but in the case of a multilayer photoreceptor, the binder resin contained in the charge generating layer is preferably 5 to 500 parts by weight, preferably 100 parts by weight of the charge generating material. Is 20 to 300 parts by weight.

  The film thickness of the charge generation layer of the multilayer photoreceptor is usually 0.05 to 5 μm, preferably 0.1 to 2 μm.

  In the case of a single layer type photoreceptor, a known one in which a photosensitive material is dispersed in a binder is used. For example, a material in which a charge generating material is dispersed as a main component in a binder resin, or a material in which a charge generating material and a charge transporting material are dispersed as main components in a binder resin is used. In these cases, the oxytitanium phthalocyanine composition according to the present invention is dispersed as a charge generation material, but other charge generation materials may be used at the same time.

  As the charge generation material, the charge transport material, and the binder resin, known materials that can be used in a multilayer photoreceptor can be used. Moreover, the solvent which can be used for the charge transport layer formation of a laminated type photoreceptor can be used suitably for the solvent of the coating liquid for photosensitive layer formation similarly.

  For example, in the case where the charge generation material and the charge transport material are the main components and dispersed in the binder resin, the oxy A titanium phthalocyanine composition is dispersed as a charge generating material. In this case, the particle size of the oxytitanium phthalocyanine composition and the charge generation material used in combination must be sufficiently small so as not to shield or scatter the exposure light, and is preferably 1 μm or less, more preferably 0. Used at 5 μm or less.

  If the amount of the charge generating material dispersed in the photosensitive layer is too small, sufficient sensitivity cannot be obtained.If the amount is too large, there is a problem such as a decrease in chargeability and sensitivity. On the other hand, it is used in the range of 0.5% by weight or more, preferably 1% by weight or more, and usually 50% by weight or less, preferably 20% by weight or less. The film thickness of the single layer type photoreceptor is usually 5 μm or more, preferably 10 μm or more, and usually 100 μm or less, preferably 50 μm or less.

<Support>
As the conductive support used in the present invention, any of those used in known electrophotographic photoreceptors can be used. Specifically, for example, drums, sheets made of metal materials such as aluminum, stainless steel, copper, nickel, etc., laminates or deposits of these metal foils, or aluminum, copper, palladium, tin oxide, indium oxide on the surface, etc. Insulating supports such as polyester film and paper provided with a conductive layer. Furthermore, a plastic film, a plastic drum, paper, a paper tube, and the like obtained by applying a conductive material such as metal powder, carbon black, copper iodide, and a polymer electrolyte together with an appropriate binder to conduct a conductive treatment may be used. Further, a plastic sheet or drum containing a conductive material such as metal powder, carbon black, or carbon fiber and becoming conductive can be used. Examples thereof include a plastic film and a belt subjected to conductive treatment with a conductive metal oxide such as tin oxide and indium oxide.

  Among these, an endless pipe made of metal such as aluminum is a preferable support. An endless pipe made of aluminum or its alloy is formed by processing such as extrusion, drawing, and ironing. What was shape | molded may be used as it is, and what added processes, such as cutting, grinding, and grinding | polishing further, may be used. The surface of the conductive support can be subjected to various treatments such as oxidation treatment and chemical treatment within a range that does not affect the image quality.

  When a metal material such as an aluminum alloy is used as the conductive support, it may be used after an anodized film is applied. When an anodized film is applied, it is desirable to perform a sealing treatment by a known method.

For example, an anodic oxidation film is formed by anodizing in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, boric acid, sulfamic acid, etc. give. In the case of anodic oxidation in sulfuric acid, the sulfuric acid concentration is 100 to 300 g / l, the dissolved aluminum concentration is 2 to 15 g / l, the liquid temperature is 15 to 30 ° C., the electrolysis voltage is 10 to 20 V, and the current density is 0.5 to Although it is preferable to set within the range of ² A / dm ² , it is not limited to the above conditions.

  It is preferable to perform a sealing treatment on the anodic oxide film thus formed. The sealing treatment may be performed by a known method. For example, it is immersed in an aqueous solution containing nickel fluoride as a main component, or immersed in an aqueous solution containing nickel acetate as a main component. A high temperature sealing treatment is preferably performed.

  The concentration of the nickel fluoride aqueous solution used in the case of the low-temperature sealing treatment can be appropriately selected, but more preferable results can be obtained when it is used in the range of 3 to 6 g / l. Moreover, in order to advance a sealing process smoothly, as processing temperature, it is 25-40 degreeC, Preferably it is 30-35 degreeC, Moreover, nickel fluoride aqueous solution pH is 4.5-6.5, Preferably it is 5 It is better to process in the range of .5 to 6.0. As the pH adjuster, oxalic acid, boric acid, formic acid, acetic acid, sodium hydroxide, sodium acetate, aqueous ammonia and the like can be used. The treatment time is preferably in the range of 1 to 3 minutes per 1 μm of film thickness. In order to further improve the physical properties of the film, cobalt fluoride, cobalt acetate, nickel sulfate, a surfactant or the like may be added to the nickel fluoride aqueous solution. Subsequently, it is washed with water and dried to finish the low temperature sealing treatment. As the sealing agent in the case of the high temperature sealing treatment, an aqueous solution of a metal salt such as nickel acetate, cobalt acetate, lead acetate, nickel acetate-cobalt, barium nitrate can be used, and it is particularly preferable to use nickel acetate. . The concentration in the case of using an aqueous nickel acetate solution is preferably 5 to 20 g / l. The treatment temperature is 80 to 100 ° C., preferably 90 to 98 ° C., and the pH of the nickel acetate aqueous solution is preferably 5.0 to 6.0. Here, ammonia water, sodium acetate, or the like can be used as the pH adjuster. The treatment time is 10 minutes or longer, preferably 15 minutes or longer. In this case as well, sodium acetate, organic carboxylic acid, anionic and nonionic surfactants may be added to the nickel acetate aqueous solution in order to improve the film properties. Subsequently, it is washed with water and dried to finish the high temperature sealing treatment. When the average film thickness is thick, stronger sealing conditions are required due to the higher concentration of the sealing liquid and high temperature / long-time treatment. Accordingly, productivity is deteriorated and surface defects such as spots, dirt, and dusting are likely to occur on the coating surface. From such a point, it is preferable that the average film thickness of the anodic oxide coating is usually 20 μm or less, particularly 7 μm or less.

  The support surface may be smooth, or may be roughened by using a special cutting method or polishing. Further, it may be roughened by mixing particles having an appropriate particle diameter with the material constituting the support. In order to reduce the cost, it is possible to use the drawing tube as it is without cutting. Especially when using non-cutting aluminum supports such as drawing, impact processing, ironing, etc., the process eliminates dirt, foreign matter, etc. on the surface, small scratches, etc., and a uniform and clean support can be obtained. Therefore, it is preferable.

<Underlayer>
An undercoat layer may be provided between the conductive support and the photosensitive layer in order to improve adhesion and blocking properties. As the undercoat layer, a resin, a resin in which particles such as a metal oxide are dispersed, or the like is used.

  Examples of metal oxide particles used for the undercoat layer include metal oxide particles containing one metal element such as titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, zinc oxide, iron oxide, calcium titanate, titanium Examples thereof include metal oxide particles containing a plurality of metal elements such as strontium acid and barium titanate. One kind of these particles may be used alone, or a plurality of kinds of particles may be mixed and used. Among these metal oxide particles, titanium oxide and aluminum oxide are preferable, and titanium oxide is particularly preferable. The surface of the titanium oxide particles may be treated with an inorganic substance such as tin oxide, aluminum oxide, antimony oxide, zirconium oxide, or silicon oxide, or an organic substance such as stearic acid, polyol, or silicon. As the crystal form of the titanium oxide particles, any of rutile, anatase, brookite, and amorphous can be used. Moreover, the thing of the several crystal state may be contained.

  Various metal oxide particle diameters can be used. Among them, the average primary particle diameter is usually 1 nm or more, preferably 10 nm, from the viewpoint of electrical characteristics and the stability of the coating liquid for forming the undercoat layer. As described above, it is usually 100 nm or less, preferably 50 nm or less.

  The undercoat layer is preferably formed in a form in which metal oxide particles are dispersed in a binder resin. As binder resin used for the undercoat layer, epoxy resin, polyethylene resin, polypropylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl chloride resin, vinyl acetate resin, phenol resin, polycarbonate resin, polyurethane resin, Polyimide resin, vinylidene chloride resin, polyvinyl acetal resin, vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol resin, polyurethane resin, polyacrylic acid resin, polyacrylamide resin, polyvinyl pyrrolidone resin, polyvinyl pyridine resin, water-soluble polyester resin, nitro Cellulose ester resins such as cellulose, cellulose ether resins, casein, gelatin, polyglutamic acid, starch, starch acetate, amino starch, zirconium chelate Compounds, organic zirconium compounds such as zirconium alkoxide compounds, titanyl chelate compounds, organic titanyl compounds such as titanyl alkoxide compound, a known binder resin such as a silane coupling agent and the like. These may be used alone or in combination of two or more in any combination and ratio. Moreover, you may use with the hardening | curing form with the hardening | curing agent. Among these, alcohol-soluble copolymerized polyamides, modified polyamides, and the like are preferable because they exhibit good dispersibility and coatability.

  The use ratio of the inorganic particles to the binder resin used in the undercoat layer can be arbitrarily selected, but is usually in the range of 10% by weight or more and 500% by weight or less from the viewpoint of dispersion stability and coatability. Is preferably used.

  The thickness of the undercoat layer can be selected arbitrarily, but is usually preferably in the range of 0.1 μm or more and 20 μm or less from the viewpoint of improving the photoreceptor characteristics and applicability.

  A known antioxidant or the like may be mixed in the undercoat layer. For the purpose of preventing image defects, pigment particles, resin particles and the like may be contained and used.

<Charge transport layer>
Examples of the charge transport material in the charge transport layer of the multilayer photoreceptor include polymer compounds such as polyvinyl carbazole, polyvinyl pyrene, polyglycidyl carbazole, and polyacenaphthylene, or indole derivatives, imidazole derivatives, pyrazole derivatives, pyrazoline derivatives, oxalates. Heterocyclic compounds such as diazole derivatives, oxazole derivatives, thiadiazole derivatives, low molecular weight compounds such as aniline derivatives, hydrazone derivatives, carbazole derivatives, stilbene derivatives, butadiene derivatives, arylamine derivatives, or a combination of these can be used. Among these, a hydrazone derivative, a carbazole derivative, a stilbene derivative, a butadiene derivative, an arylamine derivative, or a combination of these is preferably used. These charge transport materials may be used alone or in combination.

  The charge transport layer can be obtained by coating and drying a coating solution obtained by dissolving these charge transport material and binder polymer in a solvent on the charge generation layer. The binder polymer is preferably a polymer that has good compatibility with the charge transport material and does not crystallize or phase-separate after formation of the coating film. Examples thereof include polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, vinyl alcohol, ethyl vinyl ether, polyvinyl acetal, polycarbonate, polyester, polyarylate, polysulfone. , Polyphenylene oxide, polyurethane, cellulose ester, cellulose ether, phenoxy resin, silicon resin, epoxy resin, and polymers obtained by introducing the above-described low molecular weight charge transfer materials into the main chain and / or side chain.

  Among these, polycarbonate resins and polyarylate resins are preferably used in view of mechanical properties such as wear resistance and compatibility between the charge transport material in the solution and the binder polymer.

  The ratio of the binder resin to the charge transporting material is usually 10 parts by weight or more, preferably 20 parts by weight or more, particularly preferably 30 parts by weight because the electrical characteristics deteriorate if the amount of the charge transporting material is too small relative to the binder resin. Used in more than part. Further, if the amount of the charge transport material is too large, the hardness of the charge transport layer decreases, wear during use increases, and the surface is damaged and image defects are liable to occur. Therefore, it is usually 200 parts by weight or less, preferably 150 parts by weight. The amount is not more than parts by weight, particularly preferably not more than 120 parts by weight.

  The thickness of the charge transport layer is usually 10 to 50 μm, preferably 13 to 35 μm.

  An electron-withdrawing compound may be added to the charge transport layer as necessary. Electron-withdrawing compounds include tetracyanoquinodimethane, dicyanoquinomethane, cyano compounds such as aromatic esters having a dicyanoquinovinyl group, nitro compounds such as 2,4,6-trinitrofluorenone, and condensation of perylene. Polycyclic aromatic compounds, diphenoquinone derivatives, quinones, aldehydes, ketones, esters, acid anhydrides, phthalides, substituted and unsubstituted salicylic acid metal complexes, substituted and unsubstituted salicylic acid metal salts, aromatic carboxylic acids And metal salts of aromatic carboxylic acids. Preferably, cyano compounds, nitro compounds, condensed polycyclic aromatic compounds, diphenoquinone derivatives, metal complexes of substituted and unsubstituted salicylic acids, metal salts of substituted and unsubstituted salicylic acids, metal complexes of aromatic carboxylic acids, aromatic carboxylic acids A metal salt is preferably used.

  The photosensitive layer of the electrophotographic photoreceptor of the present invention has a film forming property, flexibility, coating property, mechanical strength, slipperiness, plasticizer, antioxidant, etc. in order to improve gas resistance properties such as ozone and NOx, It may contain an ultraviolet absorber, inorganic particles, resin particles, wax, silicone oil, leveling agent, and the like.

<Other functional layers>
An overcoat layer may be used on the photosensitive layer in order to improve mechanical properties and gas resistant properties such as ozone and NOx. Furthermore, you may have an adhesive layer, an intermediate | middle layer, a transparent insulating layer, etc. as needed.

  Further, an intermediate layer may be further provided between the undercoat layer and the photosensitive layer. However, in the present invention, it is preferable from the viewpoint of productivity and cost that such an intermediate layer is not provided.

<Layer formation method>
The photosensitive layer and other functional layers are formed by coating a coating solution on a conductive support by a known coating method such as a spray method, a spiral method, a ring method, or a dipping method.

  Examples of the spray used in the spray method include air spray, airless spray, electrostatic air spray, electrostatic airless spray, rotary atomizing electrostatic spray, hot spray, and hot airless spray. In order to make the film thickness uniform, a method using a rotary atomizing electrostatic spray described in Republished Hei 1-805198 is preferable.

  Examples of the spiral method include a method using an injection coating machine or a curtain coating machine described in Japanese Patent Laid-Open No. 52-119651, and a method in which a paint is streaked from a minute opening described in Japanese Patent Laid-Open No. 1-2231966. And a method using a multi-nozzle body disclosed in JP-A-3-193161.

  The immersion method will be described below. Using an organic conductive compound, binder, solvent and the like, a suitable total solid content concentration is 1% or more, more preferably 40% or less, and the viscosity is usually 1 centipoise to 700 centipoise or less, preferably 1 centipoise to 500 Adjust the coating solution for the photosensitive layer below centipoise. Here, the viscosity of the coating solution is substantially determined by the type and molecular weight of the binder polymer, but if the molecular weight is too low, the mechanical strength of the polymer itself is lowered, so that the binder has a molecular weight that does not impair this. It is preferred to use a polymer. A photosensitive layer is formed by a dip coating method using the coating solution thus adjusted.

  Thereafter, the coating film is dried, and the drying temperature time may be adjusted so that necessary and sufficient drying is performed. The drying temperature is usually 100 to 250 ° C, preferably 110 to 170 ° C, more preferably 115 to 140 ° C. As a drying method, a hot air dryer, a steam dryer, an infrared dryer, a far infrared dryer, or the like can be used.

  The electrophotographic photoreceptor thus obtained has high sensitivity, low residual potential, high chargeability, and small fluctuation due to repetition. Especially, the image quality deteriorates due to gas generated in the machine and external light during maintenance. Can be used as a high-performance and highly durable photoconductor. Further, since the sensitivity in the region of 750 to 850 nm or 580 to 700 nm is high, it is particularly suitable for a photoconductor for a semiconductor laser printer having an exposure means using a semiconductor laser diode in the region.

<Image forming apparatus>
Next, an embodiment of an image forming apparatus using the electrophotographic photosensitive member of the present invention (an image forming apparatus of the present invention) will be described with reference to FIG. However, the embodiment is not limited to the following description, and can be arbitrarily modified without departing from the gist of the present invention.

  As shown in FIG. 1, the image forming apparatus includes an electrophotographic photosensitive member 1, a charging device 2, an exposure device 3, and a developing device 4, and further, a transfer device 5, a cleaning device 6 and a fixing device as necessary. A device 7 is provided.

  The electrophotographic photoreceptor 1 is not particularly limited as long as it is the above-described electrophotographic photoreceptor of the present invention, but in FIG. 1, as an example, a drum in which the above-described photosensitive layer is formed on the surface of a cylindrical conductive support. The photoconductor is shown. A charging device 2, an exposure device 3, a developing device 4, a transfer device 5, and a cleaning device 6 are disposed along the outer peripheral surface of the electrophotographic photosensitive member 1.

  The charging device 2 charges the electrophotographic photosensitive member 1 and uniformly charges the surface of the electrophotographic photosensitive member 1 to a predetermined potential. As the charging device, a corona charging device such as a corotron or a scorotron, a direct charging device (contact type charging device) for charging a direct charging member such as a charging brush to which a voltage is applied by contacting the surface of the photosensitive member, and the like are often used. Examples of direct charging means include contact chargers such as charging rollers and charging brushes. In FIG. 1, a roller-type charging device (charging roller) is shown as an example of the charging device 2. As the direct charging means, either charging with air discharge or injection charging without air discharge is possible. It is also possible to use a proximity charging method in which charging is performed in a state in which a resin sheet or the like is wound around the charging roller and the photosensitive member and the charging roller are kept in a non-contact state at a stable charging distance. Moreover, as a voltage applied at the time of charging, it is possible to use only a direct current voltage or to superimpose alternating current on direct current.

  The type of the exposure apparatus 3 is not particularly limited as long as it can expose the electrophotographic photoreceptor 1 to form an electrostatic latent image on the photosensitive surface of the electrophotographic photoreceptor 1. Specific examples include halogen lamps, fluorescent lamps, lasers such as semiconductor lasers and He—Ne lasers, LEDs, and the like. Further, exposure may be performed by a photoreceptor internal exposure method. As the digital electrophotographic system, it is preferable to use a laser, an LED, an optical shutter array, or the like. The light used for the exposure is arbitrary. For example, the exposure may be performed using monochromatic light with a wavelength of 780 nm, monochromatic light with a wavelength slightly shorter than 600 nm to 700 nm, or monochromatic light with a short wavelength of 380 nm to 500 nm. .

  The type of the developing device 4 is not particularly limited, and an arbitrary device such as a dry development method such as cascade development, one-component insulating toner development, one-component conductive toner development, or two-component magnetic brush development, or a wet development method is used. be able to. In FIG. 1, the developing device 4 includes a developing tank 41, an agitator 42, a supply roller 43, a developing roller 44, and a regulating member 45, and has a configuration in which toner T is stored inside the developing tank 41. . Further, a replenishing device (not shown) for replenishing the toner T may be attached to the developing device 4 as necessary. The replenishing device is configured to be able to replenish toner T from a container such as a bottle or a cartridge. The development method may be either a contact method or a non-contact method. As the toner to be used, in addition to the pulverized toner, chemical toners such as suspension granulation, suspension polymerization, and emulsion polymerization aggregation method can be used. In particular, in the case of chemical toners, those having a small particle size of about 4 to 8 μm are used, and those having a shape close to a sphere, and those outside the potato and rugby ball shape can also be used. The polymerized toner is excellent in charging uniformity and transferability and is suitably used for high image quality.

  The supply roller 43 is formed from a conductive sponge or the like. The developing roller 44 is made of a metal roll such as iron, stainless steel, aluminum, or nickel, or a resin roll obtained by coating such a metal roll with a silicon resin, a urethane resin, a fluorine resin, or the like. The surface of the developing roller 44 may be smoothed or roughened as necessary.

  The developing roller 44 is disposed between the electrophotographic photoreceptor 1 and the supply roller 43 and is in contact with the electrophotographic photoreceptor 1 and the supply roller 43, respectively. The supply roller 43 and the developing roller 44 are rotated by a rotation drive mechanism (not shown). The supply roller 43 carries the stored toner T and supplies it to the developing roller 44. The developing roller 44 carries the toner T supplied by the supply roller 43 and contacts the surface of the electrophotographic photosensitive member 1.

  The regulating member 45 is formed of a resin blade such as silicon resin or urethane resin, a metal blade such as stainless steel, aluminum, copper, brass, phosphor bronze, or a blade obtained by coating such a metal blade with resin. The regulating member 45 contacts the developing roller 44 and is pressed against the developing roller 44 side with a predetermined force by a spring or the like (a general blade linear pressure is 5 to 500 g / cm). If necessary, the regulating member 45 may be provided with a function of imparting charging to the toner T by frictional charging with the toner T.

  The agitator 42 is rotated by a rotation driving mechanism, and agitates the toner T and conveys the toner T to the supply roller 43 side. A plurality of agitators 42 may be provided with different blade shapes and sizes.

  The type of the transfer device 5 is not particularly limited, and an apparatus using an arbitrary system such as an electrostatic transfer method such as corona transfer, roller transfer, or belt transfer, a pressure transfer method, or an adhesive transfer method can be used. . Here, it is assumed that the transfer device 5 includes a transfer charger, a transfer roller, a transfer belt, and the like that are disposed to face the electrophotographic photoreceptor 1. The transfer device 5 applies a predetermined voltage value (transfer voltage) having a polarity opposite to the charging potential of the toner T, and transfers the toner image formed on the electrophotographic photosensitive member 1 to a recording paper (paper, medium) P. Is.

  There is no restriction | limiting in particular about the cleaning apparatus 6, Arbitrary cleaning apparatuses, such as a brush cleaner, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, can be used. The cleaning device 6 is for scraping off residual toner adhering to the photoreceptor 1 with a cleaning member and collecting the residual toner. However, when there is little or almost no toner remaining on the surface of the photoreceptor, the cleaning device 6 may be omitted.

  The fixing device 7 includes an upper fixing member (fixing roller) 71 and a lower fixing member (fixing roller) 72, and a heating device 73 is provided inside the fixing member 71 or 72. FIG. 1 shows an example in which a heating device 73 is provided inside the upper fixing member 71. As the upper and lower fixing members 71 and 72, known heat fixing members such as a fixing roll in which a metal base tube such as stainless steel or aluminum is coated with silicon rubber, a fixing roll coated with a fluororesin, or a fixing sheet are used. be able to. Further, each of the fixing members 71 and 72 may be configured to supply a release agent such as silicone oil in order to improve releasability, or may be configured to forcibly apply pressure to each other by a spring or the like.

  When the toner transferred onto the recording paper P passes between the upper fixing member 71 and the lower fixing member 72 heated to a predetermined temperature, the toner is heated to a molten state and cooled after passing through the recording paper. Toner is fixed on P.

  There is no particular limitation on the type of the fixing device, and fixing by any method such as the one used here, heat roller fixing, flash fixing, oven fixing, pressure fixing, IH fixing, belt fixing, IHF fixing, etc. A device can be provided. Any of these known methods can be used, and these fixing methods may be used singly or in combination of a plurality of fixing methods.

  In the electrophotographic apparatus configured as described above, an image is recorded as follows. That is, first, the surface (photosensitive surface) of the photoreceptor 1 is charged to a predetermined potential (for example, −600 V) by the charging device 2. At this time, charging may be performed by a DC voltage, or charging may be performed by superimposing an AC voltage on the DC voltage.

  Subsequently, the photosensitive surface of the charged photoreceptor 1 is exposed by the exposure device 3 according to the image to be recorded, and an electrostatic latent image is formed on the photosensitive surface. The developing device 4 develops the electrostatic latent image formed on the photosensitive surface of the photoreceptor 1.

  The developing device 4 thins the toner T supplied by the supply roller 43 with a regulating member (developing blade) 45 and has a predetermined polarity (here, the same polarity as the charging potential of the photosensitive member 1) and the negative polarity. ), And conveyed while being carried on the developing roller 44 to be brought into contact with the surface of the photoreceptor 1.

  When the charged toner T carried on the developing roller 44 comes into contact with the surface of the photoreceptor 1, a toner image corresponding to the electrostatic latent image is formed on the photosensitive surface of the photoreceptor 1. This toner image is transferred onto the recording paper P by the transfer device 5. Thereafter, the toner remaining on the photosensitive surface of the photoreceptor 1 without being transferred is removed by the cleaning device 6.

  After the transfer of the toner image onto the recording paper P, the final image is obtained by passing the fixing device 7 and thermally fixing the toner image onto the recording paper P.

  In addition to the above-described configuration, the image forming apparatus may be configured to perform, for example, a static elimination process. The neutralization step is a step of neutralizing the electrophotographic photosensitive member by exposing the electrophotographic photosensitive member, and a fluorescent lamp, an LED, or the like is used as the neutralizing device. In addition, the light used in the static elimination process is often light having an exposure energy that is at least three times that of the exposure light.

  The image forming apparatus may be further modified. For example, the image forming apparatus may be configured to perform a pre-exposure process, an auxiliary charging process, or the like, or may be configured to perform offset printing. A full-color tandem system configuration using toner may be used.

  The electrophotographic photosensitive member 1 is combined with one or more of the charging device 2, the exposure device 3, the developing device 4, the transfer device 5, the cleaning device 6, and the fixing device 7 to form an integrated cartridge ( The electrophotographic photosensitive member cartridge may be configured to be detachable from a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the charging unit 3, the developing unit 4, and the cleaning unit 6 can be integrally supported together with the drum-shaped photoreceptor 1 to form a cartridge. In this case, for example, when the electrophotographic photosensitive member 1 and other members are deteriorated, the electrophotographic photosensitive member cartridge is removed from the main body of the image forming apparatus, and another new electrophotographic photosensitive member cartridge is mounted on the main body of the image forming apparatus. This facilitates maintenance and management of the image forming apparatus.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

<Production Example 1>
Under a nitrogen atmosphere, 66.6 g of phthalonitrile was suspended in 353 ml of diphenylmethane, and a mixed solution of 15.0 g of titanium tetrachloride and 25 ml of diphenylmethane was added at 40 ° C. After raising the temperature to 205-210 ° C. over about 1 hour, a mixed solution of 10.0 g of titanium tetrachloride and 16 ml of diphenylmethane was added dropwise and reacted at 205-210 ° C. for 5 hours. The product was filtered hot at 130 to 140 ° C., and then washed successively with N-methylpyrrolidone (hereinafter referred to as NMP) and n-butanol. Next, after heating and refluxing in 600 ml of n-butanol, NMP, water, and methanol were washed and dried to obtain 47.0 g of B-type oxytitanium phthalocyanine. The B-type oxytitanium phthalocyanine 20.0 g was shaken with 120 ml of glass beads (φ1.0 mm to φ1.4 mm) in a paint shaker for 25 hours, and the oxytitanium phthalocyanine was washed out with methanol and filtered to produce amorphous oxytitanium. Phthalocyanine was obtained. After suspending this oxytitanium phthalocyanine in 210 ml of water, further adding 40 ml of toluene, stirring at 60 ° C. for 1 hour, discarding the water by decantation, washing with methanol, filtering and drying crystals 19.0 g of the target oxytitanium phthalocyanine composition was obtained by the conversion operation. The powder X-ray diffraction spectrum by CuKα characteristic X-ray of the obtained oxytitanium phthalocyanine composition is shown in FIG. In this X-ray diffraction spectrum, a maximum diffraction peak was observed at a Bragg angle (2θ ± 0.2 °) of 27.3 °. The mass spectrum of the obtained oxytitanium phthalocyanine composition is shown in FIG. 3. In the mass spectrum, a peak of unsubstituted oxytitanium phthalocyanine was observed at m / z: 576, and a peak of chlorinated oxytitanium phthalocyanine at m / z: 610. When the ratio of the peak intensity of chlorinated oxytitanium phthalocyanine to the peak intensity of unsubstituted oxytitanium phthalocyanine was measured 5 times, it was in the range of 0.026 to 0.029.

  In the production example and the comparative production example of the present application, in order to measure the powder X-ray diffraction spectrum of the oxytitanium phthalocyanine composition, the measuring apparatus is a powder X-ray diffractometer of a concentrated optical system using CuKα rays as a radiation source. PW1700 made by the manufacturer was used. Measurement conditions are: X-ray output 40 kV, 30 mA, scanning range (2θ) 3-40 °, scanning step width 0.05 °, scanning speed 3.0 ° / min, divergence slit 1.0 °, scattering slit 1.0 The light receiving slit was 0.2 mm.

<Production Example 2>
Same as Production Example 1 except that a mixed solution of 18.8 g of titanium tetrachloride and 31 ml of diphenylmethane was added at 40 ° C., and a drop amount at 205 to 210 ° C. was changed to a mixed solution of 6.2 g of titanium tetrachloride and 10 ml of diphenylmethane. And 46.8 g of B-type oxytitanium phthalocyanine was obtained. By subjecting 20.0 g of this B-type oxytitanium phthalocyanine to the same crystal conversion operation as in Production Example 1, 17.6 g of the desired oxytitanium phthalocyanine composition was obtained. In the powder X-ray diffraction spectrum by CuKα characteristic X-ray of the obtained oxytitanium phthalocyanine composition, a maximum diffraction peak was observed at a Bragg angle (2θ ± 0.2 °) of 27.3 °. In the mass spectrum of the oxytitanium phthalocyanine composition, the intensity ratio of the peak of m / z: 610 chlorinated oxytitanium phthalocyanine with respect to the intensity of the unsubstituted oxytitanium phthalocyanine at m / z: 576 was measured five times. However, it was the range of 0.039-0.043.

<Production Example 3>
Same as Production Example 1 except that a mixed liquid of 12.5 g of titanium tetrachloride and 21 ml of diphenylmethane was added at 40 ° C., and a dropping amount at 205 to 210 ° C. was a mixed liquid of 12.5 g of titanium tetrachloride and 21 ml of diphenylmethane. And 44.6 g of B-type oxytitanium phthalocyanine was obtained. By subjecting 20.0 g of this B-type oxytitanium phthalocyanine to the same crystal conversion operation as in Production Example 1, 16.1 g of the target oxytitanium phthalocyanine composition was obtained. In the powder X-ray diffraction spectrum by CuKα characteristic X-ray of the obtained oxytitanium phthalocyanine composition, a maximum diffraction peak was observed at a Bragg angle (2θ ± 0.2 °) of 27.3 °. In the mass spectrum of the oxytitanium phthalocyanine composition, the intensity ratio of the peak of m / z: 610 chlorinated oxytitanium phthalocyanine with respect to the intensity of the unsubstituted oxytitanium phthalocyanine at m / z: 576 was measured five times. However, it was the range of 0.020-0.022.

<Production Example 4>
Same as Production Example 1 except that a mixed liquid of 22.5 g of titanium tetrachloride and 37 ml of diphenylmethane was added at 40 ° C., and a dropping amount at 205 to 210 ° C. was a mixed liquid of 2.5 g of titanium tetrachloride and 4 ml of diphenylmethane. To 48.2 g of B-type oxytitanium phthalocyanine. By subjecting 20.0 g of this B-type oxytitanium phthalocyanine to the same crystal conversion operation as in Production Example 1, 18.3 g of the target oxytitanium phthalocyanine composition was obtained. In the powder X-ray diffraction spectrum by CuKα characteristic X-ray of the obtained oxytitanium phthalocyanine composition, a maximum diffraction peak was observed at a Bragg angle (2θ ± 0.2 °) of 27.3 °. In the mass spectrum of the oxytitanium phthalocyanine composition, the intensity ratio of the peak of m / z: 610 chlorinated oxytitanium phthalocyanine with respect to the intensity of the unsubstituted oxytitanium phthalocyanine at m / z: 576 was measured five times. However, it was the range of 0.049-0.053.

<Production Example 5>
As in Production Example 1, except that a mixture of 7.5 g of titanium tetrachloride and 12 ml of diphenylmethane was added at 40 ° C., and the dropwise addition amount at 205 to 210 ° C. was changed to a mixture of 17.5 g of titanium tetrachloride and 29 ml of diphenylmethane. This gave 42.7 g of B-type oxytitanium phthalocyanine. 20.0 g of this B-type oxytitanium phthalocyanine was treated by the same crystal conversion operation as in Production Example 1 to obtain 18.2 g of an oxytitanium phthalocyanine composition. The powder X-ray diffraction spectrum by CuKα characteristic X-ray of the obtained oxytitanium phthalocyanine composition is shown in FIG. In this X-ray diffraction spectrum, the maximum diffraction peak was observed at a Bragg angle (2θ ± 0.2 °) of 27.3 °, but the 26.2 ° peak was higher in peak intensity than the 27.3 ° peak. 11.4% was present. Further, FIG. 7 shows a mass spectrum of the obtained oxytitanium phthalocyanine composition. In the mass spectrum of the oxytitanium phthalocyanine composition, m / z: The intensity ratio of the peak of chlorinated oxytitanium phthalocyanine at z: 610 was measured five times and found to be in the range of 0.012 to 0.014.

<Production Example 6>
As in Production Example 1, except that a mixed solution of 2.5 g of titanium tetrachloride and 4 ml of diphenylmethane was added at 40 ° C., and a dropping amount at 205 to 210 ° C. was changed to a mixed solution of 22.5 g of titanium tetrachloride and 37 ml of diphenylmethane. And 33.5 g of B-type oxytitanium phthalocyanine was obtained. When 15.0 g of this B-type oxytitanium phthalocyanine was treated by the same crystal conversion operation as in Production Example 1, a Bragg angle (2θ ± 0.2 °) of 27.3 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-rays was obtained. 12.8 g of an oxytitanium phthalocyanine composition in which a maximum diffraction peak was observed in the sample and a peak at 26.2 ° was also present was obtained. In the powder X-ray diffraction spectrum of this oxytitanium phthalocyanine composition, the peak at 26.2 ° was 14.2% in peak intensity with respect to the peak at 27.3 °. In the mass spectrum of the obtained oxytitanium phthalocyanine composition, the intensity ratio of the peak of m / z: 610 chlorinated oxytitanium phthalocyanine to the intensity of the peak of unsubstituted oxytitanium phthalocyanine at m / z: 576 is When measured five times, it was in the range of 0.0071 to 0.0085.

<Comparative Production Example 1>
Under a nitrogen atmosphere, 66.6 g of phthalonitrile was dissolved in 436 ml of 1-chloronaphthalene, and a mixed solution of 25.0 g of titanium tetrachloride and 21 ml of 1-chloronaphthalene was added dropwise at 200 ° C. After reacting at 205-210 ° C for 5 hours, the product was hot filtered at 130-140 ° C. Subsequently, after heating and refluxing in 580 ml of n-butanol, water, NMP, and methanol were washed with water and dried to obtain 48.7 g of B-type oxytitanium phthalocyanine. The B-type oxytitanium phthalocyanine (30.0 g) is shaken with 200 ml of glass beads (φ1.0 mm to φ1.4 mm) in a paint shaker for 20 hours, and the oxytitanium phthalocyanine is washed out with methanol and filtered to form amorphous oxytitanium phthalocyanine. Got. After suspending this oxytitanium phthalocyanine in 625 ml of water, 48 ml of orthodichlorobenzene is further added and stirred at room temperature for 1 hour. After discarding the water by decantation, washing with methanol, filtering and drying. The target oxytitanium phthalocyanine composition 29.0g was obtained by crystal conversion operation. FIG. 4 shows a powder X-ray diffraction spectrum by CuKα characteristic X-ray of the obtained oxytitanium phthalocyanine composition. In this X-ray diffraction spectrum, a maximum diffraction peak was observed at a Bragg angle (2θ ± 0.2 °) of 27.3 °. The mass spectrum of this oxytitanium phthalocyanine composition is shown in FIG. 5. In the mass spectrum of the oxytitanium phthalocyanine composition, m / z: 610 relative to the peak intensity of unsubstituted oxytitanium phthalocyanine at m / z: 576. The intensity ratio of the peak of chlorinated oxytitanium phthalocyanine was measured 5 times and was in the range of 0.055 to 0.057.

<Comparative Production Example 2>
Comparative production except that a mixed solution of 10.0 g of titanium tetrachloride and 16 ml of 1-chloronaphthalene was added at 25 ° C., and a dripping amount at 200 ° C. was changed to a mixed solution of 15.0 g of titanium tetrachloride and 25 ml of 1-chloronaphthalene. In the same manner as in Example 1, 49.5 g of B-type oxytitanium phthalocyanine was obtained. When 30.0 g of this B-type oxytitanium phthalocyanine was treated by the same crystal conversion operation as in Comparative Production Example 1, a Bragg angle (2θ ± 0.2 °) of 27. Although a maximum diffraction peak was observed at 3 °, 28.5 g of an oxytitanium phthalocyanine composition having a peak at 28.6 ° was also obtained. In the powder X-ray diffraction spectrum of this oxytitanium phthalocyanine composition, the peak at 28.6 ° was 16.3% with respect to the peak at 27.3 °. In the mass spectrum of the obtained oxytitanium phthalocyanine composition, the intensity ratio of the peak of m / z: 610 chlorinated oxytitanium phthalocyanine to the intensity of the peak of unsubstituted oxytitanium phthalocyanine at m / z: 576 is When measured 5 times, it was in the range of 0.081 to 0.085.

<Example 1>
Using a conductive support in which an aluminum vapor deposition layer (thickness 70 nm) is formed on the surface of a biaxially stretched polyethylene terephthalate resin film (thickness 75 μm), the following undercoat layer dispersion is applied on the aluminum vapor deposition layer of the support. The undercoat layer was formed by applying with a bar coater such that the film thickness after drying was 1.25 μm and drying.

  After drying a slurry obtained by mixing a rutile type titanium oxide having an average primary particle diameter of 40 nm (“TTO55N” manufactured by Ishihara Sangyo Co., Ltd.) and 3% by weight of methyldimethoxysilane with respect to the titanium oxide in a ball mill. Further, the hydrophobic treated titanium oxide obtained by washing with methanol and drying was dispersed with a ball mill in a methanol / 1-propanol mixed solvent to obtain a hydrophobized treated titanium oxide dispersed slurry. The dispersion slurry, a mixed solvent of methanol / 1-propanol / toluene, and ε-caprolactam [following formula A] / bis (4-amino-3-methylcyclohexyl) methane [following formula B] / hexamethylenediamine [following The composition molar ratio of the formula C] / decamethylene dicarboxylic acid [following formula D] / octadecamethylene dicarboxylic acid [following formula E] is 75% / 9.5% / 3% / 9.5% / 3%. By stirring and mixing with the copolymerized polyamide pellets to dissolve the polyamide pellets, the weight ratio of methanol / 1-propanol / toluene is 7/1/2 by performing ultrasonic dispersion treatment. Thus, a dispersion for an undercoat layer containing a hydrophobically treated titanium oxide / copolymerized polyamide at a weight ratio of 3/1 and having a solid content concentration of 18.0% was obtained.

  As a charge generation material, 20 parts by weight of an oxytitanium phthalocyanine composition having a powder X-ray diffraction spectrum pattern with respect to CuKα characteristic X-rays shown in FIG. 2 produced in Production Example 1 and 280 parts by weight of 1,2-dimethoxyethane are mixed. Then, a dispersion was prepared by dispersing for 2 hours in a sand grind mill. This dispersion, 400 parts by weight of a 2.5% by weight 1,2-dimethoxyethane solution of polyvinyl butyral (trade name “Denkabutyral” # 6000C, manufactured by Denki Kagaku Kogyo Co., Ltd.), and 170% by weight of 1,2-dimethoxyethane The coating solution for charge generation layer was prepared by mixing the part. The charge generation layer coating solution thus obtained was applied onto the undercoat layer with a bar coater so that the film thickness after drying was 0.4 μm, and dried to form a charge generation layer. .

  The charge generation layer coating solution was applied to a non-reflective cover glass so that the film thickness after drying was 10 μm or more, and dried at room temperature to prepare a sample for measuring the X-ray diffraction spectrum of the photosensitive layer.

  In order to measure an X-ray diffraction spectrum, a diffractometer (Rigaku RINT2000) for a thin film sample using CuKα rays monochromatically parallelized by an artificial multilayer mirror as a radiation source was used as a measuring apparatus. The measurement conditions are: X-ray output 50 kV / 250 mA, fixed incident angle (θ) 1.0 °, scanning range (2θ) 3-40 °, scan step width 0.05 °, incident solar slit 5.0 °, incident The X-ray diffraction spectrum by the CuKα characteristic of the obtained measurement sample was measured at a slit of 0.1 mm and a light receiving solar slit of 0.1 °. This X-ray diffraction spectrum is shown in FIG. In this X-ray diffraction spectrum, the peak intensity at the Bragg angle (2θ ± 0.2 °) of 27.3 ° is 72% larger than the peak intensity of 9.5 °, and after the baseline correction is 27.3 °. The peak intensity was 127% greater than the peak intensity of 9.5 °.

  Next, 50 parts by weight of a composition (A) described in JP-A No. 2002-080432, mainly composed of the following structure as a charge transport material, on this charge generation layer, binder resin (A) 100 having the following structure A solution prepared by dissolving 0.05 part by weight of silicone oil as a leveling agent and 640 parts by weight of a tetrahydrofuran / toluene (8/2) mixed solvent was applied so that the film thickness after drying was 25 μm. After drying at 125 ° C. for 20 minutes, an electrophotographic photosensitive member was prepared by providing a charge transport layer. This photoreceptor is referred to as a photoreceptor 1A.

<Example 2>
A charge generation layer coating solution was prepared in the same manner as in Example 1 except that 20 parts by weight of the oxytitanium phthalocyanine composition prepared in Production Example 2 was used as the charge generation material. This charge generation layer coating solution was applied to a non-reflective cover glass so that the film thickness after drying was 10 μm or more, and dried at room temperature to prepare a sample for measuring the X-ray diffraction spectrum of the photosensitive layer. The X-ray diffraction spectrum was measured in the same manner as in Example 1. In this X-ray diffraction spectrum, the peak intensity at the Bragg angle (2θ ± 0.2 °) of 27.3 ° is 56% larger than the peak intensity of 9.6 °, and after the baseline correction is 27.3 °. The peak intensity was 99% greater than the peak intensity at 9.6 °. Further, a photoconductor 2A was produced in the same manner as in Example 1 except that the charge generation layer coating solution was used.

<Example 3>
As a charge generation material, 20 parts by weight of the oxytitanium phthalocyanine composition obtained in Production Example 3 and 280 parts by weight of 1,2-dimethoxyethane are mixed and dispersed for 1 hour using an ultrasonic oscillator. Was made. This dispersion and 10 parts by weight of polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name “Denkabutyral” # 6000C), 253 parts by weight of 1,2-dimethoxyethane, 85 parts by weight of 4-methoxy-4- Methyl-2-pentanone was mixed and further diluted with 527 parts by weight of 1,2-dimethoxyethane, and the resulting liquid was dispersed with an ultrasonic oscillator for 1 hour to prepare a coating solution for charge generation layer. This charge generation layer coating solution was applied to a non-reflective cover glass so that the film thickness after drying was 10 μm, and dried at room temperature to prepare a sample for measuring the X-ray diffraction spectrum of the photosensitive layer. The X-ray diffraction spectrum was measured in the same manner as in Example 1. In this X-ray diffraction spectrum, the peak intensity at the Bragg angle (2θ ± 0.2 °) of 27.3 ° is 100% larger than the peak intensity of 9.6 °, and after the baseline correction is 27.3 °. The peak intensity was 153% greater than the peak intensity of 9.6 °.

  Further, the same operation as in Example 1 was performed using the charge generation layer coating solution, to prepare a photoreceptor 3A.

<Example 4>
Except that 20 parts by weight of the oxytitanium phthalocyanine composition obtained in Production Example 4 was used as the charge generation material, an X-ray diffraction spectrum was measured in the same manner as in Example 1 to prepare Photoreceptor 4A. In this X-ray diffraction spectrum, the peak intensity at the Bragg angle (2θ ± 0.2 °) of 27.3 ° is 32% larger than the peak intensity of 9.6 °, and after the baseline correction is 27.3 °. The peak intensity was 51% greater than the peak intensity at 9.6 °.

<Example 5>
Except that 20 parts by weight of an oxytitanium phthalocyanine composition having a powder X-ray diffraction spectrum pattern with respect to CuKα characteristic X-rays shown in FIG. Then, the X-ray diffraction spectrum was measured, and a photoreceptor 5A was produced. An X-ray diffraction spectrum is shown in FIG. In this thin film X-ray diffraction spectrum, the peak intensity at the Bragg angle (2θ ± 0.2 °) of 27.3 ° is 55% larger than the peak intensity of 9.6 °, and after the baseline correction is 27.3 °. The peak intensity was 96% greater than the peak intensity of 9.6 °. The peak intensity at 26.2 ° was larger than the powder X-ray diffraction spectrum at the time of manufacture.

<Example 6>
Except that 20 parts by weight of the oxytitanium phthalocyanine composition obtained in Production Example 6 was used as the charge generation material, an X-ray diffraction spectrum was measured in the same manner as in Example 1 to prepare Photoreceptor 6A. In this X-ray diffraction spectrum, the peak intensity at the Bragg angle (2θ ± 0.2 °) of 27.3 ° is 52% larger than the peak intensity of 9.6 °, and after the baseline correction is 27.3 °. The peak intensity was 79% greater than the peak intensity at 9.6 °. The peak intensity at 26.2 ° was larger than the powder X-ray diffraction spectrum at the time of manufacture.

<Comparative Example 1>
Except for using 20 parts by weight of an oxytitanium phthalocyanine composition having a powder X-ray diffraction spectrum pattern for the CuKα characteristic X-ray shown in FIG. Then, an X-ray diffraction spectrum was measured to produce a photoreceptor 1B. An X-ray diffraction spectrum is shown in FIG. In this X-ray diffraction spectrum, the peak intensity at a Bragg angle (2θ ± 0.2 °) of 27.3 ° is smaller than the peak intensity at 9.3 ° and is 85% of the peak intensity at 9.3 °. .

<Comparative Example 2>
Except that 20 parts by weight of the oxytitanium phthalocyanine composition obtained in Comparative Production Example 2 was used as the charge generation material, an X-ray diffraction spectrum was measured in the same manner as in Example 1 to prepare Photoreceptor 2B. In this X-ray diffraction spectrum, the peak intensity at a Bragg angle (2θ ± 0.2 °) of 27.3 ° was smaller than the peak intensity at 9.3 °, and was 92% of the peak intensity at 9.3 °. .

<X-ray diffraction spectrum of photosensitive layer>
Intensities of Bragg angles (2θ ± 0.2 °) of 27.3 °, 9.3 °, and 26.2 ° in the X-ray diffraction spectra of the photosensitive layers of Examples 1 to 6 and Comparative Examples 1 and 2. Table 1 below summarizes the ratio and the intensity ratio of 27.3 ° and 9.3 ° after the baseline correction.

  The X-ray spectrum of the layer formed using the dispersion for charge generation layer obtained by dispersing oxytitanium phthalocyanine produced using diphenylmethane solvent in Production Examples 1 to 6 has a peak intensity of 27.3 °. Was larger than the peak intensity of the maximum peak in the range of 9.0 ° to 9.8 °, whereas the oxytitanium phthalocyanine produced in the chloronaphthalene solvent of Comparative Production Examples 1 and 2 was obtained by dispersion treatment. In the X-ray spectrum of the layer formed using the charge generation layer dispersion, the maximum peak intensity of 9.0 ° to 9.8 ° was larger than the 27.3 ° peak intensity.

  Further, it is formed using the dispersion liquid for charge generation layer obtained by dispersing oxytitanium phthalocyanine in Production Example 5 and Production Example 6 in which the mass spectral intensity ratio of chlorinated oxytitanium phthalocyanine is 0.015 or less. In the X-ray spectrum of the obtained layer, an A-type peak at 26.2 ° was observed.

  And the layer formed using the dispersion liquid for charge generation layers obtained by dispersing oxytitanium phthalocyanine having a mass spectral intensity ratio of chlorinated oxytitanium phthalocyanine of 0.070 or more in Comparative Production Example 2 In the X-ray spectrum, a B-type peak at 28.6 ° was observed.

<Evaluation of electrical characteristics of photoconductor>
An electrophotographic characteristic evaluation apparatus (basic and applied electrophotographic technology, edited by the Electrophotographic Society, Corona Corp., 404) produced from the obtained photoreceptors 1A to 6A and the photoreceptors 1B to 2B according to the electrophotographic society measurement standard. ˜page 405), and electrical characteristics were evaluated by a cycle of charging, exposure, potential measurement, and static elimination.

The surface of the photoconductor was charged with an initial surface potential of −700 V under the conditions of an air temperature of 25 ° C. and a relative humidity of 50%, and the surface of the halogen lamp was irradiated with light of 780 nm monochromatic light using an interference filter. Irradiation energy (μJ / cm ² ) when the potential was −350 V was defined as sensitivity. Moreover, the residual electric potential (-V) after static elimination light irradiation was measured using LED light of 660 nm for static elimination light. The results are shown in Table 2.

  As shown in Tables 1 and 2, the photoreceptors 1A to 4A prepared using oxytitanium phthalocyanine in which the ratio of chlorinated oxytitanium phthalocyanine is 0.015 to 0.070 in mass spectral intensity ratio is In the X-ray spectrum of the layer formed using the dispersion for charge generation layer obtained by dispersing oxytitanium phthalocyanine, the peak intensity at 27.3 ° peak intensity is 9.0 ° to 9.8 °. In the evaluation of the electrical characteristics of the photoconductor, both the sensitivity and the residual potential were very excellent. The mass spectral intensity ratio of the chlorinated oxytitanium phthalocyanine is outside the range of 0.015 to 0.070, but was formed using a dispersion for charge generation layer obtained by dispersing the oxytitanium phthalocyanine. In the X-ray spectrum of the layer, the photoconductor 5A and the photoconductor 6A in which the peak intensity of the 27.3 ° peak intensity was larger than the maximum peak intensity of 9.0 ° to 9.8 ° are the photoconductors 1A to 1A. Although it was inferior to 4A, it showed excellent sensitivity and residual potential.

  On the other hand, using the dispersion liquid for charge generation layer obtained by dispersing the oxytitanium phthalocyanine, wherein the mass spectral intensity ratio of the chlorinated oxytitanium phthalocyanine is outside the range of 0.015 to 0.070. In the X-ray spectrum of the formed layer, the electric characteristics of the photoconductor 1B and the photoconductor 2B in which the peak intensity at 27.3 ° is smaller than the peak intensity of the maximum peak at 9.0 ° to 9.8 ° are as follows. It was inferior to the photoreceptors 1A to 6A according to the invention.

  Hereinafter, the electrophotographic photoreceptor and the image forming apparatus of the present invention were evaluated by performing an image formation test and a stability / durability test of the photoreceptor.

<Example 7>
The coating solution for the charge generation layer and the charge transport layer prepared in the same manner as in Example 1 was sequentially applied by dip coating on an aluminum tube having a diameter of 3 cm and a length of 25.4 cm that had been anodized and sealed. Application and drying were performed to produce an electrophotographic photosensitive drum having a film thickness of 0.3 μm and a charge transport layer of 25 μm. This drum is mounted on a Hewlett Packard laser printer, Laser Jet 4 (LJ4), and an image test is performed under conditions of an air temperature of 25 ° C. and a relative humidity of 50% (hereinafter sometimes referred to as N / N environment). As a result, a good image free from image defects and noise was obtained. Subsequently, 10,000 sheets were continuously printed, but no image degradation such as ghosting and fogging was observed, and no image defect due to leakage occurred.

<Comparative Example 3>
In Example 7, instead of using the same coating liquid as in Example 1, a photosensitive drum was prepared in the same manner as in Example 7 except that the same coating liquid as in Comparative Example 1 was used. The image test was conducted in the same manner as above. Initially, good images without image defects and noise were obtained. Subsequently, when 10,000 sheets were continuously printed, image deterioration due to fogging was recognized.

<Example 8>
The coating solution for the charge generation layer and the charge transport layer prepared in the same manner as in Example 3 was sequentially applied by dip coating on an aluminum tube having a diameter of 2 cm and a length of 25.1 cm, which had been anodized and sealed. The electrophotographic photosensitive drum having a charge generation layer of 0.3 μm and a charge transport layer of 15 μm was prepared by coating and drying. When four drums were mounted on a Fuji Xerox tandem color laser printer, C1616, and an image test was performed in an N / N environment, a good image free from image defects and noise was obtained. Subsequently, 1 million sheets were continuously printed, but no image deterioration such as leakage, ghost, or fog was observed, and the printing was stable.

<Comparative Example 4>
In Example 8, instead of using the same coating solution as in Example 2, a photosensitive drum was prepared in the same manner as in Example 8 except that the same coating solution as in Comparative Example 2 was used. The image test was conducted in the same manner as above. Initially, good images without image defects and noise were obtained. Subsequently, when 1 million sheets were continuously printed, a decrease in density was observed as compared with Example 8.

<Example 9>
The coating solution for the charge generation layer and the charge transport layer prepared in the same manner as in Example 3 was sequentially applied by dip coating on an aluminum tube having a diameter of 2 cm and a length of 25.1 cm, which had been anodized and sealed. The electrophotographic photosensitive drum having a charge generation layer of 0.3 μm and a charge transport layer of 15 μm was prepared by coating and drying. Four of these drums were mounted on Fuji Xerox's tandem color laser printer, C1616, and an image test was conducted under conditions of an air temperature of 5 ° C. and a relative humidity of 10%. was gotten. Subsequently, continuous printing of 1 million sheets was performed, but no image degradation such as ghosting and fogging was observed, and no image defects due to leakage occurred.

<Comparative Example 5>
In Example 9, instead of using the same coating solution as in Example 3, a photosensitive drum was prepared in the same manner as in Example 9 except that the same coating solution as in Comparative Example 2 was used. As a result of the image test, a good image free from image defects and noise was obtained. Next, continuous printing of 1 million sheets was performed. Compared with the image obtained in Example 9, a decrease in density was observed, and a relatively strong ghost was observed in the blue image.

<Example 10>
A subbing layer, a charge generation layer and a charge transport layer coating solution prepared in the same manner as in Example 1 were sequentially coated on an aluminum tube having a diameter of 2 cm and a length of 25.1 cm by a dip coating method and dried. However, an electrophotographic photosensitive drum having an undercoat layer of 1.25 μm, a charge generation layer of 0.3 μm, and a charge transport layer of 15 μm was produced. When four drums were mounted on a Fuji Xerox tandem color laser printer, C1616, and an image test was conducted under conditions of 35% air temperature and 85% relative humidity, a good image free from image defects and noise was obtained. was gotten. Subsequently, 1 million sheets were continuously printed, but no image deterioration such as leakage, ghost, or fog was observed, and the printing was stable.

<Comparative Example 6>
In Example 10, instead of using the same coating solution as in Example 1, a photosensitive drum was prepared in the same manner as in Example 10 except that the same coating solution as in Comparative Example 2 was used. As a result of the image test, a good image free from image defects and noise was obtained. Next, when 1 million sheets were continuously printed, density reduction occurred. In addition, image degradation due to partial leakage was also observed.

  As can be seen from the above examples and comparative examples, by using the charge transport material of the present invention, an electrophotographic photoreceptor excellent in electrical characteristics, stability and durability, and an image forming apparatus using the same Can be provided. Further, it is possible to provide an electrophotographic photosensitive member that can be applied to an electrophotographic apparatus such as a printer, a facsimile machine, and a copying machine with high image quality and low toner consumption. In addition, it is possible to obtain a photoconductor excellent in repetitive characteristics and printing durability under environmental fluctuations, particularly high temperature, high humidity / low temperature, and low humidity.

  It can be applied to electrophotographic apparatuses such as printers, facsimiles, and copiers, and can provide a high-sensitivity electrophotographic photosensitive member with high sensitivity and low residual potential.

1 is a schematic diagram illustrating a main configuration of an embodiment of an image forming apparatus of the present invention. 3 is a powder X-ray diffraction spectrum of the oxytitanium phthalocyanine composition obtained in Production Example 1. FIG. 2 is a mass spectrum of an oxytitanium phthalocyanine composition obtained in Production Example 1. 3 is a powder X-ray diffraction spectrum of an oxytitanium phthalocyanine composition obtained in Comparative Production Example 1. FIG. 2 is a mass spectrum of an oxytitanium phthalocyanine composition obtained in Comparative Production Example 1. FIG. 6 is a powder X-ray diffraction spectrum of an oxytitanium phthalocyanine composition obtained in Production Example 5. FIG. 6 is a mass spectrum of an oxytitanium phthalocyanine composition obtained in Production Example 5. 2 is a thin film X-ray diffraction spectrum of a photosensitive layer using the oxytitanium phthalocyanine composition obtained in Example 1. FIG. 2 is a thin film X-ray diffraction spectrum of a photosensitive layer using the oxytitanium phthalocyanine composition obtained in Comparative Example 1. 4 is a thin film X-ray diffraction spectrum of a photosensitive layer using the oxytitanium phthalocyanine composition obtained in Example 5.

Explanation of symbols

1 Photoconductor 2 Charging device (charging roller)
DESCRIPTION OF SYMBOLS 3 Exposure apparatus 4 Developing apparatus 5 Transfer apparatus 6 Cleaning apparatus 7 Fixing apparatus 41 Developing tank 42 Agitator 43 Supply roller 44 Developing roller 45 Control member 71 Upper fixing member (fixing roller)
72 Lower fixing member (fixing roller)
73 Heating device T Toner P Recording paper (paper, medium)

Claims (7)

  An oxytitanium phthalocyanine composition having a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray, the chlorinated oxytitanium in the composition An oxytitanium phthalocyanine composition, wherein the ratio of phthalocyanine is 0.015 to 0.070 in terms of mass spectral intensity ratio to unsubstituted oxytitanium phthalocyanine.   The oxytitanium phthalocyanine composition according to claim 1, wherein the oxytitanium phthalocyanine composition is obtained by reacting phthalonitrile and a titanium halide using a non-halogenated solvent as a reaction solvent. object.   The oxytitanium phthalocyanine composition according to claim 1, wherein the oxytitanium phthalocyanine composition is obtained by reacting phthalonitrile and titanium halide using a diarylalkane as a reaction solvent.   An electrophotographic photosensitive member having a photosensitive layer containing the oxytitanium phthalocyanine composition according to any one of claims 1 to 3 on a conductive support, and a thin film X-ray by CuKα characteristic X-ray of the photosensitive layer The diffraction spectrum has at least one strong diffraction peak at Bragg angle (2θ ± 0.2 °) from 9.0 ° to 9.8 °, and a strong diffraction peak at 27.3 °, and 27.3 The peak intensity at ° is 10% or more larger than the peak intensity of the maximum peak between 9.0 ° and 9.8 °, and the peak intensity at 27.3 ° is the maximum diffraction peak among all diffraction peaks. An electrophotographic photoreceptor.   An electrophotographic photosensitive member having a photosensitive layer containing the oxytitanium phthalocyanine composition according to any one of claims 1 to 3 on a conductive support, and a thin film X-ray by CuKα characteristic X-ray of the photosensitive layer The diffraction spectrum has at least one strong diffraction peak at a Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.8 ° and a strong diffraction peak at 27.3 °, and has a baseline. The peak intensity at 27.3 ° after correction is 25% or more larger than the peak intensity after correcting the baseline of the maximum peak between 9.0 ° and 9.8 °, and the peak intensity at 27.3 ° Is the largest diffraction peak among all diffraction peaks. The electrophotographic photosensitive member according to claim 4 or 5 , wherein the oxytitanium phthalocyanine composition contained in the photosensitive layer does not contain a 26.2 ° peak in a powder X-ray diffraction spectrum.   An image forming apparatus using the electrophotographic photosensitive member according to claim 4.

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