JP2008019417A - Phthalocyanine crystal, electrophotographic photoreceptor, and electrophotographic photoreceptor cartridge and image forming apparatus utilizing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an excellent phthalocyanine crystal that exhibits high sensitivity and is reduced in the variation in sensitivity due to the change of humidity in use environment, and thus is suitable for use as a material of solar cell, electronic paper, electrophotographic photoreceptor, etc. <P>SOLUTION: There is provided a phthalocyanine crystal prepared through a step of bringing a phthalocyanine crystal precursor into contact with an aromatic aldehyde compound to thereby attain a crystal-type conversion. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a phthalocyanine crystal obtained by converting a crystal form of a phthalocyanine crystal precursor, an electrophotographic photosensitive member, an electrophotographic photosensitive member cartridge, and an image forming apparatus using the phthalocyanine crystal. In particular, it has high sensitivity to LED light and semiconductor laser light, and there are few variations in sensitivity to changes in the humidity of the usage environment, and it can be suitably used as a material for solar cells, electronic paper, electrophotographic photoreceptors, The present invention relates to an excellent phthalocyanine crystal, and an electrophotographic photosensitive member, an electrophotographic photosensitive member cartridge, and an image forming apparatus that have high sensitivity and are less sensitive to changes in humidity in a use environment.

  In recent years, organic optical devices that use organic photoconductive materials and can be used for solar cells, electronic paper, electrophotography, and the like have been intensively studied. Among these, in particular, the electrophotographic technique is excellent in immediacy and can obtain a high-quality image. Therefore, in recent years, it has been widely applied not only to the field of copying machines but also to various printers and printing machines.

  As an electrophotographic photoreceptor (hereinafter abbreviated as “photoreceptor” as appropriate) which is the core of electrophotographic technology, conventionally, a photoreceptor using an inorganic photoconductive material such as selenium, an arsenic-selenium alloy or zinc oxide is used. In recent years, photoconductors using organic photoconductive materials that have the advantages of being pollution-free, easy to form and manufacture, and having a high degree of freedom in material selection and combination have become mainstream. It has become.

  The sensitivity of an electrophotographic photoreceptor using an organic photoconductive material varies depending on the wavelength of exposure light and the type of charge generating substance.

  As a charge generating substance having sensitivity to light having a long wavelength of 600 to 800 nm, phthalocyanine compounds have attracted attention, and in particular, chloroaluminum phthalocyanine, chloroindium phthalocyanine, oxyvanadium phthalocyanine, hydroxygallium phthalocyanine, chlorogallium phthalocyanine, Researches on metal-containing phthalocyanines such as magnesium phthalocyanine and oxytitanium phthalocyanine, or metal-free phthalocyanines have been conducted energetically.

  Regarding phthalocyanine compounds, it has been reported that even if the monomolecular structure is the same, the charge generation efficiency differs depending on the arrangement order (crystal type) of crystals that are aggregates of single molecules (non-patent literature). 1 and 2).

  With the recent speeding up and full color of electrophotographic processes in copiers, laser printers, plain paper fax machines, etc., higher sensitivity and faster response are indispensable as the characteristics of electrophotographic photoreceptors. Development of new charge generating materials is essential.

  For high sensitivity, a charge generation material having a high charge generation capability is essential. Among them, active research has been conducted on oxytitanium phthalocyanine, which is highly sensitive to LD exposure, which is currently the mainstream. The oxytitanium phthalocyanine is known to exhibit crystal polymorphism. Known crystal types include α-type (see Patent Literature 1), β-type (see Patent Literature 2), C-type (see Patent Literature 3), D-type (see Patent Literature 4), and Y-type (see Patent Literature 5). ), M type (refer to Patent Document 6), M-α type (refer to Patent Document 7), I type (refer to Patent Document 8), etc., have been reported.

  Among these crystal types, a crystal type having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to CuKα characteristic X-ray (wavelength 1.541Å) (hereinafter sometimes referred to as “specific crystal type” as appropriate). Are known to exhibit high quantum efficiency and high sensitivity.

  In addition to crystals composed only of oxytitanium phthalocyanine molecules alone, mixed crystals composed of oxytitanium phthalocyanine and other phthalocyanines and other pigments form the above specific crystal type and exhibit high sensitivity. Is widely known (see Patent Document 9).

  The phthalocyanine crystal types containing the specific crystal type oxytitanium phthalocyanine are known to have very high sensitivity. This high sensitivity is thought to be manifested by the presence of water molecules in the crystal and functioning as a sensitizer, and the water molecules acting as the sensitizer are in the environment where the crystals are placed. The inside and outside of the crystal can be freely moved in and out due to the change in humidity, and when the humidity of the environment where the crystal is placed becomes low, water molecules are detached from the crystal and the sensitivity is lowered.

  The decrease in sensitivity due to the desorption of water molecules due to this decrease in humidity is due to the normal humidity and the low humidity after drying when used as an electrophotographic photoreceptor in laser printers, copiers, etc. It appears as a problem that the obtained image density is different between the two images output in (1). In particular, in full-color laser printers and copiers that have become widespread in recent years, a decrease in image density has become a major issue because it is noticeable due to changes in the color tone of full-color images.

  As described above, the phthalocyanine crystal type containing the specific crystal type oxytitanium phthalocyanine has high sensitivity, but has a problem that the characteristics greatly change due to changes in the environment in which it is used.

  On the other hand, V-type hydroxygallium phthalocyanine has been reported as a charge generating substance that has less change in electrical characteristics with respect to change in humidity than the specific crystal type oxytitanium phthalocyanine. This V-type hydroxygallium phthalocyanine has an advantage that the sensitivity fluctuation with respect to the humidity change is very small, but the sensitivity is inferior to that of the specific crystal type oxytitanium phthalocyanine, and the number of sheets per unit time has increased in recent years. In the present situation, the electrical characteristics are insufficient to meet the demand for a high-speed image forming apparatus that performs full-color printing (see Non-Patent Document 3).

  Furthermore, in order to suppress the sensitivity change with respect to the humidity change of the specific crystal type oxytitanium phthalocyanine, a method of adding a moisturizing agent to the charge generation layer has been reported (see Patent Documents 10 to 12). Only the humidity dependency related to the residual potential is improved, and the sensitivity fluctuation due to the humidity change is not sufficiently improved. Since image degradation due to humidity is likely to occur not in a solid black image but in a halftone image, it is necessary to reduce variations in sensitivity. Actually, in the light decay curve of the specific crystal type oxytitanium phthalocyanine, it is known that the fluctuation of the potential portion related to the halftone (the absolute value of the potential is around 100 to 300 V) is large with respect to the change in humidity. However, the request to reduce the potential fluctuation is still insufficient.

Journal of Electrophotographic Society, Vol. 29, No. 3, pp. 250-258 Journal of Electrophotographic Society, Vol. 32, No. 3, pp. 282-289 Fuji Xerox Technical Report No.12 1998 JP-A-61-217050 JP-A 62-67094 JP-A-63-366 JP-A-2-8265 JP 63-20365 A JP-A-3-54265 JP-A-3-54264 Japanese Patent Laid-Open No. 3-128973 Japanese Patent Laid-Open No. 3-9962 JP 2003-207912 A JP 2003-186217 A JP 2003-215825 A

  Phthalocyanine crystals having the above specific crystal type (hereinafter referred to as “phthalocyanine crystals”) include not only crystals composed of only one kind of phthalocyanine compound, but also mixed crystals composed of a plurality of kinds of phthalocyanine compounds, phthalocyanine compounds and others. All crystals containing a phthalocyanine compound are included, including mixed crystals composed of the above-mentioned molecules, and “phthalocyanine compound” will be described later.) Shows very high sensitivity. This high sensitivity is manifested by the presence of water molecules in the crystal and functioning as a sensitizer, but the water molecules acting as the sensitizer are not sensitive to the humidity of the environment in which the crystals are placed. Since the inside and outside of the crystal are freely moved in and out with the change, there is a problem that when the humidity is lowered, water molecules are detached from the crystal and the sensitivity is lowered.

  The problem of reduced sensitivity due to desorption of water molecules due to this decrease in humidity is a problem when phthalocyanine crystals having the above specific crystal type are used as materials for electrophotographic photoreceptors in laser printers, copiers, etc. This presents a problem that the obtained image density differs between an image output in a humidity state and an image output in a dry and low humidity state. In particular, in full-color laser printers and copiers that have become widespread in recent years, a reduction in image density is a significant problem because it appears significantly as a change in color tone of a full-color image.

  The phthalocyanine crystal having the specific crystal type is produced by bringing a phthalocyanine as a precursor into contact with a specific compound and converting the crystal type. In this crystal type conversion step, the crystal type is constructed by the interaction between the compound molecules used and the phthalocyanines. At this time, the interaction with the phthalocyanines differs depending on the compound used, and various crystals are produced depending on the production method. Shows type and particle shape. In addition, the characteristics of the electrophotographic photosensitive member such as charge generation capability (sensitivity), chargeability, and dark decay depend on the manufacturing method, and it is very difficult to predict the performance in advance.

  As described above, the phthalocyanine crystal having the specific crystal type has high sensitivity, but has a problem that the characteristics greatly change due to changes in the environment in which it is used. As mentioned above, high-sensitivity and low-sensitivity electrophotography for laser printers, copiers, etc. that can print many sheets per unit time with high image quality, which has become the mainstream in recent years Photoconductors are widely desired, but have not been developed yet.

  The present invention has been made in view of the above demand. That is, an object of the present invention is to provide a phthalocyanine crystal having high sensitivity and low sensitivity fluctuation with respect to humidity change in the use environment, and high sensitivity and little sensitivity fluctuation with respect to humidity change in the use environment. An electrophotographic photosensitive member and an image forming apparatus capable of providing an image having a stable image quality against humidity change in the use environment by using the electrophotographic photosensitive member. Is to provide.

  The present inventors presume that the compound used for converting the crystal form of the phthalocyanine crystal precursor is deeply involved in the sensitivity fluctuation with respect to the change in humidity of the obtained electrophotographic photosensitive member, and solves the above problems. As a result of diligent investigation, the phthalocyanine crystal obtained by converting the crystal form of the phthalocyanine crystal precursor in the presence of a specific compound has high sensitivity, and there is a fluctuation in sensitivity to humidity changes in the usage environment. It has been found that an electrophotographic photosensitive member can be obtained with a small amount and a high sensitivity and a small sensitivity fluctuation with respect to a change in humidity in the use environment, and the present invention has been completed.

  That is, the gist of the present invention resides in a phthalocyanine crystal characterized by being obtained through a step of converting a crystal form by bringing a phthalocyanine crystal precursor into contact with an aromatic aldehyde compound (claim 1).

  Another gist of the present invention is an organic compound that does not have a functional group that exhibits acidity in the presence of at least one compound selected from the group consisting of organic acids, organic acid anhydrides, and organic acid esters having heteroatoms. In addition, the phthalocyanine crystal is obtained through a step of converting a crystal form by contacting with a phthalocyanine crystal precursor (claim 2).

  Further, another gist of the present invention is solid under conditions of 1013 hPa and 25 ° C., and is in a liquid state under conditions of 1013 hPa and 25 ° C. in the presence of an aromatic compound having an electron-withdrawing substituent. The present invention resides in a phthalocyanine crystal obtained by a step of converting a crystal form by bringing an organic compound having no acidic functional group into contact with a phthalocyanine crystal precursor (claim 3).

  Another gist of the present invention is a step of converting a crystal form by bringing a phthalocyanine crystal precursor into contact with an aromatic compound having an oxygen atom-containing group and a halogen atom having an atomic weight of 30 or more as a substituent. The phthalocyanine crystal is obtained through the following (claim 4).

  Here, the group containing an oxygen atom is preferably a group selected from the group consisting of an organic group having a carbonyl group, a nitro group, and an ether group.

  In any of the above phthalocyanine crystals, the step of converting the crystal form of phthalocyanine is preferably performed in the presence of water (claim 6).

  In addition, it is preferable that any of the above phthalocyanine crystals contains at least oxytitanium phthalocyanine.

  Further, any of the above phthalocyanine crystals preferably has a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to CuKα characteristic X-ray (wavelength 1.541Å). .

  Another gist of the present invention is an electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer contains any of the phthalocyanine crystals described above. (Claim 9).

Another gist of the present invention is that an electrophotographic photosensitive member having a photosensitive layer with a film thickness of 35 ± 2.5 μm on a conductive support has a half-exposure amount E _{1 / at} a temperature of 25 ° C. and a relative humidity of 50% rh. ₂ satisfies the following formula (1), and when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half-exposure dose E An electrophotographic photosensitive member is characterized in that the absolute value of the difference in surface potential at the same exposure dose is less than 50 V in the range of exposure dose of 0 to 10 times _1/2 .
E _1/2 ≦ 0.059 (1)
(In the above formula (1), E _1/2 represents the exposure amount of light having a wavelength of 780 nm (μJ) required to attenuate the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V. / Cm ² )

Another gist of the present invention is an electrophotographic photosensitive member having a photosensitive layer with a thickness of 30 ± 2.5 μm on a conductive support, and a half-exposure amount E _{1 / at} a temperature of 25 ° C. and a relative humidity of 50% rh. ₂ satisfies the following formula (2), and when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half-exposure amount E An electrophotographic photosensitive member is characterized in that the absolute value of the difference in surface potential at the same exposure dose is less than 50 V in the range of exposure dose of 0 to 10 times _1/2 .
E _1/2 ≦ 0.061 (2)
(In the above formula (2), E _1/2 represents the exposure amount of light having a wavelength of 780 nm (μJ) required to attenuate the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V. / Cm ² )

Another gist of the present invention is an electrophotographic photosensitive member having a photosensitive layer with a film thickness of 25 ± 2.5 μm on a conductive support, and a half-exposure amount E _{1 / at} a temperature of 25 ° C. and a relative humidity of 50% rh. ₂ satisfies the following formula (3), and when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half-exposure dose E An electrophotographic photosensitive member is characterized in that the absolute value of the difference in surface potential at the same exposure dose is less than 50 V in the range of exposure dose of 0 to 10 times _1/2 .
E _1/2 ≦ 0.066 (3)
(In the above formula (3), E _1/2 is the exposure amount of light having a wavelength of 780 nm (μJ required for attenuating the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V) / Cm ² )

Another gist of the present invention is that an electrophotographic photosensitive member having a photosensitive layer with a thickness of 20 ± 2.5 μm on a conductive support has a half-exposure amount E _{1 / at} a temperature of 25 ° C. and a relative humidity of 50% rh. ₂ satisfies the following formula (4), and when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half-exposure amount E An electrophotographic photosensitive member is characterized in that the absolute value of the difference in surface potential at the same exposure dose is less than 50 V in the range of exposure dose of 0 to 10 times _1/2 .
E _1/2 ≦ 0.079 (4)
(In the above formula (4), E _1/2 is the exposure amount of light having a wavelength of 780 nm (μJ required for attenuating the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V) / Cm ² )

Another gist of the present invention is an electrophotographic photosensitive member having a photosensitive layer having a film thickness of 15 ± 2.5 μm on a conductive support, and a half-exposure amount E _{1 / at} a temperature of 25 ° C. and a relative humidity of 50% rh. ₂ satisfies the following formula (5), and when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half-exposure dose E An electrophotographic photosensitive member is characterized in that the absolute value of the difference in surface potential at the same exposure dose is less than 50 V in the range of exposure dose of 0 to 10 times _1/2 .
E _1/2 ≦ 0.090 (5)
(In the above formula (5), E _1/2 is the exposure amount of light having a wavelength of 780 nm (μJ) required to attenuate the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V. / Cm ² )

  Here, in any of the above-described electrophotographic photoreceptors, it is preferable that the photosensitive layer contains oxytitanium phthalocyanine (claim 15).

  Here, in any of the above-described electrophotographic photoreceptors, it is preferable that the photosensitive layer contains any of the above-mentioned phthalocyanine crystals.

  Another gist of the present invention is any one of the above-described electrophotographic photosensitive members, a charging unit for charging the electrophotographic photosensitive member, and exposure for forming the electrostatic latent image by exposing the charged electrophotographic photosensitive member. An electrophotographic photosensitive member comprising: a developing unit that develops an electrostatic latent image formed on the electrophotographic photosensitive member; and a cleaning unit that cleans the electrophotographic photosensitive member. It exists in a cartridge (Claim 17).

  Another gist of the present invention is that any one of the above-described electrophotographic photosensitive members, a charging unit for charging the electrophotographic photosensitive member, and exposing the charged electrophotographic photosensitive member to form an electrostatic latent image. An image forming apparatus comprising: an exposure unit; and a developing unit that develops an electrostatic latent image formed on the electrophotographic photosensitive member.

The phthalocyanine crystal of the present invention has an advantage that it has a high sensitivity and has a small variation in sensitivity to changes in humidity in the usage environment.
In addition, the electrophotographic photosensitive member of the present invention has an advantage that it has high sensitivity and is less sensitive to changes in humidity in the usage environment.
In addition, the electrophotographic photosensitive member cartridge and the image forming apparatus of the present invention have an advantage that an image having a stable image quality can be provided with respect to a change in humidity of the use environment.

  Hereinafter, the present invention will be described in detail, but the present invention is not limited to the following description, and various modifications can be made within the scope of the gist of the present invention.

[I. Phthalocyanine crystal]
The phthalocyanine crystal of the present invention is a step of converting a crystal form by bringing a phthalocyanine crystal precursor into contact with a specific compound in the presence of a specific compound as necessary (hereinafter referred to as “crystal type conversion step” as appropriate). It may be obtained through

  Here, in the crystal form conversion step, specific compounds for contacting the phthalocyanine crystal precursor (hereinafter sometimes referred to as “contact compounds for crystal form conversion” as appropriate), and at that time, coexist if necessary. Specific compounds (hereinafter sometimes referred to as “coexisting compounds for crystal form conversion” as appropriate. Also, contact compounds for crystal form conversion and coexisting compounds for crystal form conversion are collectively referred to as “compounds for crystal form conversion” as appropriate. Depending on the type, the following (A) to (D) are classified.

(A) A crystalline form is converted by bringing a phthalocyanine crystal precursor into contact with an aromatic aldehyde compound. That is, an aromatic aldehyde compound is used as the contact compound for crystal type conversion (hereinafter, this aromatic aldehyde compound may be referred to as “crystal type conversion compound (A)”).

(B) The phthalocyanine crystal precursor is present in the presence of at least one compound selected from the group consisting of an organic acid, an organic acid anhydride, and an organic acid ester having a hetero atom (hereinafter referred to as “specific organic acid compound” as appropriate). The crystal form is converted by contacting with an organic compound having no acidic functional group (hereinafter referred to as “non-acidic organic compound” as appropriate). That is, a specific organic acid compound is used as a coexisting compound for crystal type conversion, and a non-acidic organic compound is used as a contact compound for crystal type conversion (hereinafter, these specific organic acid compound and non-acidic organic compound are combined). It may be referred to as “crystal-type conversion compounds (B)”).

(C) The phthalocyanine crystal precursor is solid under the conditions of 1013 hPa and 25 ° C., and in the presence of an aromatic compound having an electron-withdrawing substituent (hereinafter referred to as “electron-withdrawing specific aromatic compound” as appropriate). The crystal form is converted by contacting with an organic compound that is in a liquid state under conditions of 1013 hPa and 25 ° C. and does not have an acidic functional group (hereinafter referred to as “non-acidic specific organic compound” as appropriate). That is, an electron-withdrawing specific aromatic compound is used as the coexisting compound for crystal type conversion, and a non-acidic specific organic compound is used as the contact compound for crystal type conversion (hereinafter referred to as these electron-withdrawing specific aromatic compound and The non-acidic specific organic compound may also be referred to as “crystal-type conversion compounds (C)”).

(D) The phthalocyanine crystal precursor is brought into contact with a group containing an oxygen atom and an aromatic compound having a halogen atom having an atomic weight of 30 or more as a substituent (hereinafter referred to as “specific substituent-containing aromatic compound” as appropriate). Thus, the crystal form is converted. That is, a specific substituent-containing aromatic compound is used as the contact compound for crystal type conversion (hereinafter, this specific substituent-containing aromatic compound may be referred to as “crystal type conversion compound (D)”).

  In the crystal type conversion step, any one of the above-mentioned crystal type conversion compounds (A) to (D) may be used alone, or two or more types of crystal type conversion may be used. The compounds may be used in any combination and ratio.

  In the following description, unless otherwise noted, common items will be collectively described regardless of the type of the crystal-type conversion compound, and each of the crystal-type conversion compounds (A) to (D) will be described. Only specific matters shall be explained individually.

[I-1. Composition of phthalocyanine crystal
In the present invention, “phthalocyanine crystal” refers to a crystal containing one or more phthalocyanine compounds. That is, not only a crystal composed of only one kind of phthalocyanine compound, but also a mixed crystal composed of a plurality of kinds of phthalocyanine compounds and a mixed crystal composed of one or more kinds of phthalocyanine compounds and other molecules. In the invention, it is referred to as “phthalocyanine crystal”.

  In the present invention, the “phthalocyanine compound” refers to a compound having a phthalocyanine skeleton. Specific examples include metal-free phthalocyanines; phthalocyanines having a planar molecular structure such as copper phthalocyanine, zinc phthalocyanine, lead phthalocyanine; oxytitanium phthalocyanine, oxyvanadium phthalocyanine, chloroaluminum phthalocyanine, chlorogallium phthalocyanine, chloroindium phthalocyanine, hydroxygallium Phthalocyanines whose molecules have a shuttlecock structure; phthalocyanines whose molecules have a top-shaped structure such as dichlorotin phthalocyanine, dichlorosilicon phthalocyanine, dihydroxytin phthalocyanine, dihydroxysilicon phthalocyanine;

  When the phthalocyanine crystal of the present invention is composed of a single type of phthalocyanine compound, a phthalocyanine compound having a shuttlecock structure is desirable in view of the characteristics as an electrophotographic photoreceptor. Further, among the phthalocyanine compounds having a shuttlecock structure, since the characteristics as an electrophotographic photoreceptor are generally good, the central metal of the phthalocyanine compound molecule is in the form of an oxide, chloride, or hydroxide. From the viewpoint of ease of production of phthalocyanine crystals, it is more preferable that the central metal take the form of an oxide. As a specific example, oxytitanium phthalocyanine or oxyvanadium phthalocyanine is particularly preferable, and oxytitanium phthalocyanine is most preferable.

  On the other hand, as a case where the phthalocyanine crystal of the present invention is a mixed crystal composed of a plurality of types of molecules, as described above, it is composed of a plurality of types of phthalocyanine compounds (that is, does not include compounds other than phthalocyanine compounds). , One or two or more phthalocyanine compounds and a compound other than one or two or more phthalocyanine compounds (that is, including compounds other than phthalocyanine compounds). From the above, it is preferred to be composed of a plurality of types of phthalocyanine compounds (that is, not containing compounds other than phthalocyanine compounds).

  When the phthalocyanine crystal of the present invention is a mixed crystal, it is preferable to contain a phthalocyanine compound having a shuttlecock structure as a main component in consideration of the characteristics as an electrophotographic photosensitive member. The phthalocyanine compound contained as the main component (hereinafter referred to as “main component phthalocyanine compound” as appropriate) is preferably such that the central metal of the molecule is in the form of an oxide, chloride or hydroxide. From the viewpoint of ease of production, it is more preferable that the central metal is in the form of an oxide. As a specific example, oxytitanium phthalocyanine or oxyvanadium phthalocyanine is particularly preferable, and oxytitanium phthalocyanine is most preferable. The content of the main component phthalocyanine compound is usually 60% by weight or more with respect to the mixed crystal phthalocyanine crystal, but if the amount contained is small, the crystal form controllability is lowered, so 70% by weight or more. It is preferably 80% by weight or more from the viewpoint of crystal stability during dispersion, and more preferably 85% by weight or more from the viewpoint of characteristics when used as an electrophotographic photoreceptor.

  Further, when the phthalocyanine crystal of the present invention is a mixed crystal, the phthalocyanine compound contained in addition to the above-mentioned main component phthalocyanine compound (hereinafter referred to as “phthalocyanine compound other than the main component” as appropriate) is stable as a mixed crystal. From the viewpoint of properties, a phthalocyanine compound having a shuttlecock structure or a phthalocyanine compound having a planar molecular structure is preferable. Among these, in terms of electrophotographic photoreceptor characteristics, among phthalocyanine compounds having a shuttlecock structure, oxyvanadium phthalocyanine, chlorogallium phthalocyanine, hydroxygallium phthalocyanine, and chloroindium phthalocyanine are preferable, and among phthalocyanine compounds having a planar structure, Metal-free phthalocyanine, zinc phthalocyanine, and lead phthalocyanine are preferred. Among these, oxyvanadium phthalocyanine, chlorogallium phthalocyanine, chloroindium phthalocyanine, hydroxygallium phthalocyanine, and metal-free phthalocyanine are more preferable, and since there are more vacant spaces in the mixed crystal, metal-free phthalocyanine having a planar molecular structure Is particularly preferred. Only one type of phthalocyanine compound other than the main component may be used, or two or more types may be used in any combination and ratio, but it is preferable to use only one type. The content of the phthalocyanine compound other than the main component is usually 40% by weight or less with respect to the phthalocyanine crystal which is a mixed crystal, but if it is too much, the crystal form controllability is lowered, so 30% by weight or less is preferable. 20% by weight or less is preferable from the viewpoint of stability during dispersion, and 15% by weight or less is preferable from the viewpoint of electrophotographic characteristics. However, if the content of the phthalocyanine compound other than the main component is too small, the effect due to the content may not be obtained. Therefore, the content is preferably 0.1% by weight or more, and 0.5% by weight or more. More preferred.

[I-2. (Phthalocyanine crystal precursor)
The phthalocyanine crystal of the present invention is obtained through a step of converting a crystal form by bringing a phthalocyanine crystal precursor into contact with a compound for crystal form conversion. Here, the “phthalocyanine crystal precursor” refers to a substance from which a phthalocyanine crystal can be obtained by performing a treatment for converting a crystal form (hereinafter sometimes referred to as “crystal form conversion treatment”). Therefore, the phthalocyanine crystal precursor may be any of a kind of phthalocyanine compound, a mixture of two or more phthalocyanine compounds, a mixture of one or two or more phthalocyanine compounds and one or two or more other compounds. (In the following description, a phthalocyanine compound or a mixture containing a phthalocyanine compound may be collectively referred to as “phthalocyanines”). In addition, the existence state is not particularly limited, but considering the controllability of the crystal type at the time of crystal conversion, the phthalocyanine crystal precursor is usually an amorphous phthalocyanine having a molecular structure identical to that of the obtained phthalocyanine crystal or a low phthalocyanine crystal. Crystalline phthalocyanines are used.

  In the present invention, “low crystalline phthalocyanines” means a Bragg to CuKα characteristic X-ray (wavelength 1.541Å) in a powder X-ray diffraction (X-ray diffraction: hereinafter sometimes abbreviated as “XRD”) spectrum. An angle (2θ ± 0.2 °) refers to phthalocyanines having no peak with a half-value width of 0.30 ° or less within a range of 0 ° to 40 °. If this half-value width is too small, the phthalocyanine molecule will have a certain degree of regularity and long-term order in the solid, and the crystal form controllability will be reduced when the crystal form is converted. From the above, the low crystalline phthalocyanines used as phthalocyanine crystal precursors in the present invention have a half-value width of usually 0.35 ° or less, more preferably 0.40 ° or less, and particularly 0.45 ° or less. It is preferable that

  In the present specification, measurement of powder X-ray diffraction spectrum of phthalocyanines, determination of Bragg angle (2θ ± 0.2 °) with respect to CuKα characteristic X-ray (wavelength 1.541 波長), and calculation of peak half-value width are as follows: It shall be performed under the following conditions.

As an apparatus for measuring a powder X-ray diffraction spectrum, a concentrated optical system powder X-ray diffractometer (for example, PW1700 manufactured by PANalytical) using CuKα (CuKα ₁ + CuKα ₂ ) rays as an X-ray source is used.

  The measurement conditions of the powder X-ray diffraction spectrum are: scanning range (2θ) 3.0-40.0 °, scan step width 0.05 °, scanning speed 3.0 ° / min, divergence slit 1 °, scattering slit 1 °. The light receiving slit is 0.2 mm.

The peak half width can be calculated by a profile fitting method. Profile fitting can be performed using, for example, powder X-ray diffraction pattern analysis software JADE5.0 + manufactured by MDI. The calculation conditions are as follows. That is, the background is fixed at an ideal position from the entire measurement range (2θ = 3.0 to 40.0 °). As the fitting function, a Peason-VII function considering the contribution of CuKα ₂ is used. Three variables of the fitting function are refined: diffraction angle (2θ), peak height, and peak half-value width (β _o ). The influence of CuKα ₂ is removed, and the diffraction angle (2θ), peak height, and peak half width (β _o ) derived from CuKα ₁ are calculated. The asymmetry is fixed at 0 and the shape constant is fixed at 1.5.

The peak half-value width (β _o ) calculated by the above profile fitting is the peak half width (2θ = 28.442 °) of the standard Si (NIST Si 640b) calculated by the same measurement conditions and the same profile fitting conditions. By correcting according to the following equation using β _Si ), the peak half-value width (β) derived from the sample is obtained.

  The boundary between the low crystalline phthalocyanines and the amorphous phthalocyanines is not clear, but any of them can be used as a preferred phthalocyanine crystal precursor in the present invention. In the following description, when the low crystalline phthalocyanines and the amorphous phthalocyanines are referred to without particular distinction, they are collectively referred to as “low crystalline / amorphous phthalocyanines”.

  As will be described later, as the crystal form of the phthalocyanine crystal of the present invention, a crystal form having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to CuKα characteristic X-ray (wavelength 1.541Å) ( Specific crystal type) is preferable, but low crystalline phthalocyanines having a peak near 27.2 ° have regularity somewhat similar to the phthalocyanine crystal having the specific crystal type. Since it is excellent in crystal form controllability, it is preferable as a phthalocyanine crystal precursor. In this case, the low crystalline phthalocyanine has a peak with a half-value width of usually 0.30 ° or less, preferably 0.35 ° or less, more preferably 0.40 ° or less, and further preferably 0.45 ° or less. It is not included.

  On the other hand, when low crystalline / amorphous phthalocyanines having no peak near 27.2 ° are used as the phthalocyanine crystal precursor, the crystal form controllability to the phthalocyanine crystal having the specific crystal type is low. In this case, the low crystalline phthalocyanine has a half width of usually 0.30 ° or less, preferably 0.50 ° or less, more preferably 0.70 ° or less, and still more preferably 0. It does not include peaks in the range of 90 ° or less.

  2 to 5 show examples of powder X-ray diffraction spectra of low crystalline / amorphous phthalocyanines. These X-ray diffraction spectra are illustrated for the purpose of explaining the present invention in detail, and phthalocyanines that can be used as phthalocyanine crystal precursors in the present invention are used unless they violate the scope of the present invention. However, the present invention is not limited to the low crystalline / amorphous phthalocyanines having these X-ray diffraction spectra.

  Crystalline phthalocyanines (phthalocyanine crystals) are usually in a state where phthalocyanine molecules have a certain regularity or long-term order in a solid, and have a clear peak when measured by a powder X-ray diffraction spectrum . On the other hand, low crystalline / amorphous phthalocyanines are in a state in which the regularity of the molecular arrangement and the long-term order of the molecular arrangement are lowered in the solid, and the powder X-ray diffraction spectrum illustrated as FIGS. Thus, even if it shows a halo figure or has a peak, its full width at half maximum is very wide.

  In the present invention, the low crystalline / amorphous phthalocyanines to be used as phthalocyanine crystal precursors are known as chemical treatment methods such as acid paste method and acid slurry method, and mechanical treatment methods such as grinding and grinding. However, since a more uniform low crystalline / amorphous phthalocyanine can be obtained, the chemical treatment method is preferable, and the acid paste method is more preferable.

[I-3. Compounds for crystal form conversion)
<I-3-1. Crystalline type conversion compounds (A)>
Crystalline conversion compounds (A) are aromatic aldehyde compounds. Aromatic aldehyde compounds are used as contact compounds for crystal form conversion.

(Aromatic aldehyde compounds)
An aromatic aldehyde compound is a compound having an aldehyde group directly bonded to an aromatic ring.

  The number of aromatic rings is not particularly limited as long as the aromatic aldehyde compound is a compound having one or more aromatic rings that satisfy the Hückel rule, but the value of n in the formula of 4n + 2 (n is an integer) in the Hückel rule Is usually 5 or less. In particular, the value of n is preferably 3 or less, more preferably 2 or less, and still more preferably 1 in consideration of the operability during crystal conversion and the electrophotographic photoreceptor characteristics of the phthalocyanine crystal.

  Aromatic ring types include aromatic hydrocarbon rings consisting of carbon and hydrogen atoms, and hetero atoms such as nitrogen, sulfur and oxygen atoms in addition to carbon and hydrogen atoms. There are aromatic heterocycles.

  Specific examples of the aromatic ring include anthracene, phenanthrene, acridine, phenanthridine, phenanthroline, phenazine, etc. when n = 3, and naphthalene, azulene, quinoline, isoquinoline, quinoxaline, naphthyridine, etc. when n = 2 In the case of 1, known aromatic hydrocarbon ring structures and aromatic heterocyclic structures such as benzene, pyridine, pyrazine, pyrrole, thiophene, furan, thiazole, oxazole and imidazole can be mentioned. The aromatic hydrocarbon ring structure and aromatic heterocyclic structure may have a condensed ring having no aromaticity in addition to the aromatic ring portion.

  The number of aldehyde groups per molecule of the aromatic aldehyde compound is not particularly limited, but is usually 1 or more, usually 4 or less, preferably 2 or less.

  Examples of the substituent that the aromatic aldehyde compound may have other than the aldehyde group include an alkyl group such as a methyl group, an ethyl group, an isopropyl group, and a cyclohexyl group; an alkoxy group such as a methoxy group, an ethoxy group, and an isopropoxy group; Aralkyloxy groups such as benzyloxy groups; aryloxy groups such as phenoxy groups; thioalkyl groups such as thiomethyl groups and thioethyl groups; aryl groups such as phenyl groups and naphthyl groups; nitro groups; cyano groups; carboxy groups; sulfo groups; Group: sulfeno group; hydroxy group; mercapto group; halogen atom such as fluorine atom, chlorine atom, bromine atom; ketone group such as acetyl group; amide group such as carboxamide group; amino group, monomethylamino group, methylethylamino group, etc. Substituted or unsubstituted amino groups; methyloxycarbonyl It is possible to known substituents, such as a halogenated alkyl group such as trifluoromethyl group; group, an ester group such as ethyloxy carbonyl group.

  Among the examples of the substituent described above, the substituent having a carbon chain in a substituent such as an alkyl group, an alkoxy group, a substituted amino group, an ester group, and a ketone group has a linear or branched carbon chain portion. Any of the cyclic structures may be used, but if the structure of the carbon chain portion of these substituents is too large, the stability of the crystal will be adversely affected, and therefore a linear or branched structure is preferred. Moreover, the carbon number of the carbon chain part in these substituents is 20 or less normally. If the carbon chain portion has too many carbon atoms, the effect of the aromatic aldehyde compound is reduced, so this carbon number is preferably 15 or less, more preferably 10 or less.

  Among the substituents, a halogen atom, an alkyl group, an alkoxy group, a ketone group, an ester group, a carboxy group, a nitro group, and the like are preferable from the viewpoint of crystal form controllability and charge generation ability, and a halogen atom, a ketone group, and an alkoxy group. Groups are more preferred.

  The number of substituents that the aromatic aldehyde compound has in addition to the aldehyde group is not particularly limited, but is preferably 5 or less, more preferably 3 or less in consideration of the operability during crystal conversion and the electrophotographic photoreceptor characteristics of the phthalocyanine crystal. Yes, more preferably 1 or less. In addition, substituents other than the aldehyde group may be bonded to each other to form a ring structure.

  Examples of the aromatic aldehyde compound include those having an aromatic hydrocarbon ring and those having an aromatic heterocyclic ring.

  Specific examples of the aromatic aldehyde compound having an aromatic hydrocarbon ring include benzaldehydes (for example, fluorobenzaldehyde, chlorobenzaldehyde, methoxybenzaldehyde, nitrobenzaldehyde, phenylbenzaldehyde, 1,2,3,4-tetrahydronaphthaldehyde, etc.) , Naphthaldehydes (1-naphthaldehyde, 2-naphthaldehyde, etc.), anthaldehydes (9-anthaldehyde, etc.).

  Specific examples of the aromatic aldehyde compound having an aromatic heterocycle include pyridinecarbaldehydes (2-pyridinecarbaldehyde, etc.), quinolinecarbaldehydes (2-quinolinecarbaldehyde, etc.), thiophenealdehydes (2-thiophenaldehyde). Etc.), pyrrole carbaldehydes (pyrrole-2-carbaldehyde, etc.).

  Among the above-mentioned aromatic aldehyde compounds, an aromatic aldehyde compound in which an aldehyde group is directly bonded to an aromatic hydrocarbon ring is preferable from the viewpoint of crystal conversion ability, and in particular, stability due to environmental fluctuation when used in an electrophotographic photoreceptor. From the viewpoint of properties, benzaldehydes are more preferable.

  As the crystalline conversion compounds (A), any one of the above-mentioned aromatic aldehyde compounds may be used alone, or two or more may be used in any combination and ratio.

  The amount of the aromatic aldehyde compound used varies depending on the method used for the contact treatment and cannot be generally defined, but is generally 50% by weight or more, preferably 100% by weight with respect to the phthalocyanine crystal precursor. % Or more, and usually in the range of 2000% by weight or less, preferably 1000% by weight or less. In addition, when using together 2 or more types of aromatic aldehyde compounds, let these total ratios satisfy | fill the said range.

  In addition, one or more aromatic aldehyde compounds may be mixed with one or more other compounds and brought into contact with the phthalocyanine crystal precursor. In this case, the type of the other compound used in combination with the aromatic aldehyde compound is not particularly limited as long as it does not undesirably affect the phthalocyanine crystal precursor to be used and the phthalocyanine crystal to be obtained. However, even when other compounds other than the aromatic aldehyde compound are used in combination, the ratio of the aromatic aldehyde compound to the total amount of the aromatic aldehyde compound and the other compound is usually 50% by weight or more, particularly 75% by weight or more. It is preferable.

<I-3-2. Crystalline type conversion compounds (B)>
The crystalline conversion compounds (B) have an acidic functional group and at least one compound (specific organic acid compound) selected from the group consisting of organic acids, organic acid anhydrides, and organic acid esters having heteroatoms. No organic compound (non-acidic organic compound). The specific organic acid compound is used as a coexisting compound for crystal type conversion, and the non-acidic organic compound is used as a contact compound for crystal type conversion.

(Specific organic acid compounds)
The specific organic acid compound is at least one compound selected from the group consisting of organic acids, organic acid anhydrides, and organic acid esters having a hetero atom.

・ Organic acid:
The organic acid is a general term for compounds showing acidity, specifically, carboxylic acid, sulfonic acid, sulfinic acid, sulfenic acid, phenol, enol, thiol, phosphonic acid, phosphoric acid, boronic acid, imidic acid, These are compounds having a functional group showing acidity (hereinafter, abbreviated as “acidic functional group” where appropriate), such as hydrazone acid, hydroxymic acid, and hydroxysamic acid.

  The organic acid used as the specific organic acid compound is not particularly limited as long as it is a compound having the various acidic functional groups described above, but is generally a carbon atom from the viewpoint of versatility and stability of the reagent. An organic acid having an acidic functional group composed of oxygen atom, sulfur atom, phosphorus atom and boron atom is used. Examples of such organic acids include carboxylic acid, sulfonic acid, sulfinic acid, phenol, thiol, phosphonic acid, phosphoric acid, boronic acid, borinic acid and the like. Of these, carboxylic acid, sulfonic acid, phenol, phosphonic acid, phosphoric acid, and boronic acid are preferred in consideration of the characteristics of the electrophotographic photoreceptor using the obtained phthalocyanine crystal as a material. Carboxylic acid, sulfonic acid, phosphonic acid, phosphoric acid are preferable. Acid and boronic acid are more preferable.

  The acidic functional group may have any known structure, but examples include a carboxyl group, a thiocarboxyl group, a dithiocarboxyl group, a mercaptocarbonyl group, a hydroperoxy group, a sulfo group, a sulfino group, a sulfeno group, and a phenolic group. Examples thereof include a hydroxyl group, a thiol group, a phosphinico group, a phosphono group, a selenono group, a selenino group, a seleneno group, an arsinico group, an arsono group, a boronic acid group, and a boranoic acid group. Among these acidic functional groups, from the viewpoint of versatility and safety of raw materials, acidic functional groups usually composed of carbon atom, oxygen atom, sulfur atom, phosphorus atom, boron atom are preferable, carboxyl group, thiocarboxyl group , Sulfo group, sulfino group, sulfeno group, phenolic hydroxyl group, thiol group, phosphinico group, phosphono group, boronic acid group, boranoic acid group are more preferable, and in terms of characteristics as an electrophotographic photoreceptor, carboxyl group, phosphinico group More preferred are a phosphono group, a sulfo group and a boronic acid group.

  The organic acid used as the specific organic acid compound exhibits the effect of the present invention by having an acidic functional group in its structure. Therefore, at least one acidic functional group may be included per organic acid molecule, but a plurality of acidic functional groups may be included. When a plurality of acidic functional groups are included in one organic acid molecule, the plurality of acidic functional groups may be the same or different from each other. However, if the number of acidic functional groups per molecule of the organic acid is too large, the solubility in the non-acidic organic compound used in combination decreases, and the effect of the present invention decreases, so the number is preferably 10 or less. Preferably it is 7 or less, more preferably 4 or less.

  From the viewpoint of structure, the organic acid can be distinguished into an acidic functional group portion and a portion other than the acidic functional group portion (organic residue portion). The structure of the acidic functional group moiety is as described above, but the structure of the organic residue moiety is not particularly limited, and may have any known structure. However, a molecule of a phthalocyanine compound (hereinafter sometimes abbreviated as “phthalocyanine molecule”) has a large number of π electrons in its structure, and a phthalocyanine crystal is formed by the interaction of π electrons developed between the phthalocyanine molecules. Because of the construction, the larger the interaction between the phthalocyanine molecule and the organic acid, the easier the organic acid can be taken into the phthalocyanine crystal. Therefore, the organic residue portion of the organic acid preferably has a structure having π electrons so that the interaction between the organic acid and the phthalocyanine molecule is strengthened. The number of π electrons in the organic residue portion is not particularly limited, and it is sufficient that at least two π electrons (that is, at least one carbon-carbon double bond) are contained in one organic acid molecule. However, from the viewpoint of enhancing the interaction with the phthalocyanine molecule, the organic residue part preferably includes a structure having aromaticity that satisfies the Hückel rule.

  The molecular weight of the organic acid used as the specific organic acid compound is not particularly limited, but is usually 50 or more, preferably 100 or more, and usually 1200 or less, preferably 1000 or less. If the molecular weight of the organic acid is too small, the solubility in water is increased, whereby the abundance in the phthalocyanine crystal is decreased and the effect of the present invention tends to be reduced. In addition, if the molecular weight of the organic acid is too large, the molecular volume of the organic acid is too large, so that the abundance in the phthalocyanine crystal is reduced and the effect of the present invention tends to be reduced. In particular, if the molecular volume of the organic residue part of the organic acid is too large, incorporation into the phthalocyanine crystal becomes difficult, so the molecular weight of the organic residue part is usually 1000 or less, preferably 500 or less, more preferably 400 or less. More preferably, it is 300 or less.

  As the state of the organic acid, the state of the organic acid as it is, the state in which the organic acid is ionized, the state in which the organic acid ion is combined with the counter ion to form a salt, and the like can be considered. Since it can be presumed that the acidic functional group moiety contributes to the expression of the effect by being incorporated into the organic acid, the organic acid used in the present invention may be in any of the above states.

  In the present invention, as described later, when the phthalocyanine crystal precursor is brought into contact with the non-acidic organic compound in the presence of the specific organic acid compound, it is preferable that water coexists. Therefore, although it is a compound other than an organic acid in the stage before the contact treatment, a compound that is converted to an organic acid by hydrolysis or the like by contact with water can also be used as the specific organic acid compound. is there. In the following description, such a compound is collectively referred to as “organic acid”.

・ Organic acid anhydride:
An organic acid anhydride is a compound having a bond in which two acyl groups share an oxygen atom (hereinafter referred to as “an acid anhydride bond” as appropriate). The main organic acid anhydrides include those in which two molecules of an organic acid having one acidic functional group form an acid anhydride bond between molecules, and one organic acid having two or more acidic functional groups. And those forming an acid anhydride bond in the molecule. The former can be further divided into those in which two types of organic acids of the same type form acid anhydride bonds and those in which two types of organic acids of different types form acid anhydride bonds. The kind of the organic acid anhydride used in the present invention is not particularly limited, and any of these organic acid anhydrides may be used.

  Examples of organic acid anhydrides include carboxylic acid anhydrides in which two molecules of the same type of carboxylic acid form an acid anhydride bond between molecules, such as acetic anhydride, propionic anhydride, butyric anhydride, and trifluoroacetic anhydride. Carboxylic acid anhydrides in which two different types of carboxylic acid molecules form an acid anhydride bond between molecules, such as acetic acid propionic acid anhydride and acetic acid trifluoroacetic acid anhydride; phthalic acid anhydride, maleic acid anhydride, anhydrous A carboxylic acid anhydride in which a dicarboxylic acid forms an acid anhydride bond in the same molecule, such as succinic acid, 1,2-naphthalic acid anhydride, 1,8-naphthalic acid anhydride; methanesulfonic acid anhydride, A sulfonic acid anhydride in which two molecules of the same or different types of sulfonic acid form an acid anhydride bond between molecules, such as benzenesulfonic acid anhydride; the same or different, such as benzenesulfinic acid anhydride Two types of organic acid dimers of the same or different types, such as sulfinic anhydride formed by forming two types of sulfinic acid bimolecules and forming an acid anhydride bond between molecules; benzenesulfonic acid, benzenesulfinic anhydride, cyclic anhydrous sulfoacetic acid, etc. Examples thereof include a chain or cyclic organic acid anhydride formed by forming an acid anhydride bond between molecules. Among these, the organic acid anhydrides used in the present invention include carboxylic acid anhydrides made of the same acid, carboxylic acid anhydrides made of different carboxylic acids, A carboxylic acid anhydride and a sulfonic acid anhydride having an acid anhydride bond are preferred, a carboxylic acid anhydride comprising the same acid, and a carboxylic acid anhydride having an acid anhydride bond in the molecule.

  The structure of the portion other than the acid anhydride bond (organic residue portion) of the organic acid anhydride used as the specific organic acid compound is not particularly limited and may be any structure. The structure having π electrons is preferable for the same reason as described in the column “. The number of π electrons in the organic residue portion is not particularly limited, and it is sufficient that at least two π electrons (that is, at least one carbon-carbon double bond) are contained in one organic acid molecule. However, from the viewpoint of enhancing the interaction with the phthalocyanine molecule, the organic residue portion preferably contains a structure having aromaticity that satisfies the Hückel rule.

  The molecular weight of the organic acid anhydride is not particularly limited, but if it is too large, it tends to be difficult to be incorporated into the phthalocyanine crystal, so it is usually 1000 or less, preferably 500 or less, more preferably 400 or less, and even more preferably 300 or less. . On the other hand, if the molecular weight of the organic acid anhydride is too low, the interaction with the phthalocyanine molecule decreases, and the amount of the organic acid anhydride in the phthalocyanine crystal tends to decrease, so the effect of the present invention tends to decrease. The lower limit of the molecular weight is usually 50 or more, preferably 100 or more.

Organic acid ester having a hetero atom:
The organic acid ester having a hetero atom is an organic compound in which the acidic functional group portion of the organic acid having a hetero atom is changed to an organic acid ester not showing acidity. Examples include a compound in which an acidic sulfone group is changed to a methyl sulfonate group so as not to exhibit acidity.

  A hetero atom generally means an atom other than a carbon atom and a hydrogen atom among atoms constituting an organic compound. However, since an organic acid usually has at least an oxygen atom and / or a nitrogen atom in an acidic functional group, when an oxygen atom and a nitrogen atom are included in a heteroatom, all organic acid esters have a heteroatom. It falls under the ester and is not appropriate as a definition. For this reason, in this invention, atoms other than a carbon atom, a hydrogen atom, a nitrogen atom, and an oxygen atom shall be defined as a hetero atom.

  In general, heteroatoms introduced into the structure of organic compounds include boron atoms, sulfur atoms, phosphorus atoms, silicon atoms, selenium atoms, tellurium atoms, etc., but the organic acid esters used in the present invention As the heteroatom contained in, usually a boron atom, a sulfur atom, or a phosphorus atom is used. Among these, in consideration of the versatility of the organic acid ester used in the present invention, a sulfur atom and a phosphorus atom are preferable.

  In the structure of the organic acid ester, the site where the hetero atom is introduced is not particularly limited and may be introduced at any site, but in the structure of the organic acid before being derived to the organic acid ester, the acidic functional group moiety It is preferable to have a hetero atom (for example, sulfo group, phosphono group, etc.). That is, the organic acid ester used in the present invention preferably has an acid ester group containing a hetero atom.

  In addition, in the structure of the organic acid ester having a hetero atom, the structure of the portion other than the acid ester group containing a hetero atom (organic residue portion) is not particularly limited, and may be any structure. For the same reason as described in the “Acid” column, a structure having π electrons is preferable. The number of π electrons in the organic residue portion is not particularly limited, and it is sufficient that at least two π electrons (that is, at least one carbon-carbon double bond) are contained in one organic acid molecule. However, from the viewpoint of enhancing the interaction with the phthalocyanine molecule, the organic residue portion preferably contains a structure having aromaticity that satisfies the Hückel rule.

  Examples of organic acid esters having heteroatoms include phosphonic acid esters such as dimethyl methylphosphonate, dimethyl phenylphosphonate, dimethyl methylphosphonate, and diethyl phenylphosphonate; phosphate esters such as dimethyl methylphosphate and dimethyl phenylphosphate, methane Sulfonic acid esters such as methyl sulfonate, methyl benzene sulfonate and ethyl benzene sulfonate; sulfinic acid esters such as methyl methyl sulfinate and methyl phenyl sulfinate; sulfino acids such as methyl sulfinoate and methyl phenyl sulfinoate Examples of the ester include boronic acid esters such as dimethyl methylboronate and dimethyl phenylboronate. Among these, phosphonic acid esters, phosphoric acid esters, sulfonic acid esters, and boronic acid esters are preferable from the viewpoint of versatility of the reagent, and phosphonic acid esters and sulfonic acid esters are more preferable.

  Although the molecular weight of the organic acid ester having a hetero atom is not particularly limited, it is usually 1000 or less, preferably 500 or less, more preferably 400 or less, and even more preferably 300 or less because it is difficult to be incorporated into the phthalocyanine crystal if it is too large. . On the other hand, if the molecular weight of the organic acid ester having a heteroatom is too low, the interaction with the phthalocyanine molecule is reduced, the amount of the organic acid ester having a heteroatom in the phthalocyanine crystal is reduced, and the effect of the present invention is reduced. Therefore, the lower limit of the molecular weight is usually 50 or more, preferably 100 or more.

・ Other:
As the specific organic acid compound, any one of the above-described organic acid, organic acid anhydride, and organic acid ester having a hetero atom is used. Any one kind of specific organic acid compound may be used alone, or two or more kinds of specific organic acid compounds may be used in any combination and ratio. In particular, when two or more kinds of specific organic acid compounds are used in combination, two or more kinds of compounds from any one of the three categories of organic acid, organic acid anhydride, and organic acid ester having a hetero atom are used. May be used in combination, or one or two or more compounds may be selected and used in combination from any two categories or all three categories.

  In addition, the presence form of the specific organic acid compound is not particularly limited, and may be any of liquid, gas, and solid.

(Non-acidic organic compounds)
The non-acidic organic compound refers to an organic compound that does not have the acidic functional group described in the column of “• Organic acid” in its structure.

  The kind of the non-acidic organic compound used in the present invention is not particularly limited as long as it has an ability to convert a crystal form.

  Non-acidic organic compounds are roughly classified into aliphatic compounds and aromatic compounds (in the following description, these will be referred to as “non-acidic aliphatic compounds” and “non-acidic aromatic compounds”, respectively). .)

  Examples of non-acidic aliphatic compounds include saturated or unsaturated aliphatic hydrocarbon compounds such as pinene, terpyrenone, hexane, cyclohexane, octane, decane, 2-methylpentane, ligroin, petroleum benzine; diethyl ether, diisopropyl ether, Aliphatic ether compounds such as dibutyl ether, dimethyl cellosolve, ethylene glycol dibutyl ether, tetrahydrofuran, 1,4-dioxane, 1,3-dioxolane; dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,2,2 Halogenated aliphatic compounds such as 1,2-tetrachloroethane; aliphatic ketone compounds such as methyl ethyl ketone, methyl isobutyl ketone, diisopropyl ketone, diisobutyl ketone, cyclohexanone, cyclopentanone; Aliphatic ester compounds such as propyl acetate, butyl acetate, isobutyl acetate, hexyl acetate, butyl acrylate, methyl propionate, cyclohexyl acetate; aliphatic alcohol compounds such as methanol, ethanol, butanol; normal propyl aldehyde, normal butyraldehyde, etc. And aliphatic aldehyde compounds. The hydrocarbon skeleton of these non-acidic aliphatic compounds may be linear (either linear or branched) or cyclic, and is a combination of linear and cyclic. There may be.

  On the other hand, examples of non-acidic aromatic compounds include aromatic hydrocarbon compounds such as toluene, xylene, naphthalene, biphenyl and terphenyl; halogens such as monochlorobenzene, dichlorobenzene, trichlorobenzene, dichlorotoluene, chloronaphthalene and bromobenzene. Aromatic nitro compounds such as nitrobenzene and fluoronitrobenzene; aromatic ester compounds such as methyl benzoate, butyl benzoate, methyl chlorobenzoate, methyl methylbenzoate, and phenyl acetate; diphenyl ether, anisole, chloroanisole, etc. Aromatic ether compounds; aromatic aldehyde compounds such as benzaldehyde and chlorobenzaldehyde; aromatic ketone compounds such as acetophenone and chloroacetophenone; thiophene, furan, quinoli , And a heterocyclic aromatic compounds picoline.

  Among these non-acidic organic compounds, an aliphatic compound, an aromatic compound, or an aromatic hydrocarbon compound containing a halogen atom or an oxygen atom is preferable from the viewpoint of crystal form conversion ability. Among these, in consideration of the stability during dispersion of the obtained phthalocyanine crystals, halogenated aliphatic compounds, aliphatic ether compounds, aliphatic ketone compounds, aliphatic ester compounds, aromatic hydrocarbon compounds, halogenated aromatic compounds, aromatics Aromatic nitro compounds, aromatic ketone compounds, aromatic ester compounds, and aromatic aldehyde compounds are more preferable. From the viewpoint of the characteristics of the electrophotographic photoreceptor using the obtained phthalocyanine crystal as a material, aliphatic ether compounds, halogenated aromatics More preferred are compounds, aromatic nitro compounds, aromatic ketone compounds, aromatic ester compounds, or aromatic aldehyde compounds.

  In addition, these non-acidic organic compounds may belong to a plurality of compound groups at the same time among the above-described compound groups depending on the types of substituents in the structure (for example, nitrochlorobenzene is a “halogenated aromatic compound”). ”And“ aromatic nitro compounds ”), but such non-acidic organic compounds are judged to have the attributes of the compound as having all the attributes of the plurality of categories. (For example, nitrochlorobenzene has the attributes of both halogenated aromatic compounds and aromatic nitro compounds).

  Any of these non-acidic organic compounds may be used alone, or two or more thereof may be used in any combination and ratio.

  The existence form of the non-acidic organic compound is not particularly limited and may be liquid, gas, or solid. However, the contact treatment between the non-acidic organic compound and the phthalocyanine crystal precursor is usually performed when the non-acidic organic compound is liquid. Therefore, the melting point of the non-acidic organic compound is usually 150 ° C. or lower, preferably 100 ° C. or lower, more preferably 80 ° C. or lower.

  The molecular weight of the non-acidic organic compound is not particularly limited, but the contact treatment between the non-acidic organic compound and the phthalocyanine crystal precursor is usually performed in a liquid state, so that the molecular weight of the non-acidic organic compound is not so high. Too large is not desirable. Specifically, the molecular weight of the non-acidic organic compound is usually 1000 or less, preferably 500 or less, more preferably 400 or less, and still more preferably 300 or less. On the other hand, if the molecular weight of the non-acidic organic compound is too low, the boiling point is generally low, and since it tends to volatilize, there is a tendency to reduce the handleability during production, so the lower limit of the molecular weight is usually 50 or more, preferably 100 or more. It is.

(Combination of specific organic acid compound and non-acidic organic compound)
An electrophotographic photoreceptor using a phthalocyanine crystal obtained as a material by using a specific organic acid compound and a non-acidic organic compound in combination as the crystal-type conversion compound (B) during the crystal conversion treatment of the phthalocyanine crystal precursor. It is not clear why the characteristics improve, but the mechanism is not clear, but by coexisting non-acidic organic compounds during the crystal conversion treatment, the specific organic acid compound used at the same time is more efficiently incorporated into the phthalocyanine crystal, It is presumed that the effect of the present invention is obtained.

<I-3-3. Crystalline type conversion compounds (C)>
The crystal-type conversion compounds (C) are solid under conditions of 1013 hPa and 25 ° C., and have an electron-withdrawing substituent (electron-withdrawing specific aromatic compound) and 1013 hPa at 25 ° C. It consists of an organic compound (non-acidic specific organic compound) that is in a liquid state under conditions and does not have an acidic functional group. The electron-withdrawing specific aromatic compound is used as a coexisting compound for crystal type conversion, and the non-acid specific organic compound is used as a contact compound for crystal type conversion.

(Electron-withdrawing specific aromatic compound)
The electron-withdrawing specific aromatic compound is an aromatic compound that is solid under conditions of 1013 hPa and 25 ° C. and has an electron-withdrawing substituent (hereinafter simply referred to as “electron-withdrawing group”).

Here, the “electron withdrawing group” refers to a substituent in which the value of the substituent constant σ _p ⁰ (hereinafter sometimes simply referred to as “substituent constant σ _p ⁰ ”) in the Hammett rule is a positive value. Shall point. Here, the “Hammett relational rule” is an empirical rule used to explain the effect of a substituent in an aromatic compound on the electronic state of an aromatic ring. II revision 4 "(published on Mar. 30, 1993, Maruzen Co., Ltd.), page 379, the pKa of the benzoic acid having the substituent was subtracted from the pKa of the unsubstituted benzoic acid. Calculated as a value. Assuming that the value of the substituent constant σ _p ⁰ is ⁰ in the case of a hydrogen atom, the value becomes a positive value having a large absolute value as the electron withdrawing property becomes high, and the negative value having a large absolute value as the electron donating property becomes high. Become. Therefore, by using this substituent constant σ _p ⁰ , it is possible to predict and represent the electronic state and electron density of the aromatic compound having a substituent. For the representative substituents, the value of the substituent constant σ _p ⁰ described in the Chemical Society of Japan, “Chemical Handbook, Basic Edition II, 4th revised edition” (issued on Mar. 30, 1993, Maruzen Co., Ltd.) Shown in Table 1 below. In the present invention, the value of the substituent constant σ _p ⁰ described in the above document is used, and the value of the substituent not described is described in “Chemicals of the Chemical Society of Japan”. Measure and calculate under the same conditions as the measurement conditions for the substituent constant σ _p ⁰ described in "Handbook Basic Edition II Revised 4th Edition" (issued on Mar. 30, 1993, Maruzen Co., Ltd.) It shall be determined by

The type of electron-withdrawing group possessed by the electron-withdrawing specific aromatic compound used in the present invention is not particularly limited as long as the value of the substituent constant σ _p ⁰ is larger than ⁰ , but the obtained electron From the standpoint of stability of the characteristics of the photographic photoreceptor against environmental fluctuations, an electron withdrawing group having a substituent constant σ _p ⁰ value of usually 0.200 or more, particularly 0.300 or more is preferable.

  The number of electron-withdrawing groups contained in the electron-withdrawing specific aromatic compound used in the present invention is not particularly limited as long as it is 1 or more, but if the number of electron-withdrawing groups is too large, the non-acidic specific organic compound In view of the decrease in the solubility in the solvent and the effect obtained, it is preferably 5 or less, more preferably 4 or less, and still more preferably 3 or less. In addition, when it has two or more electron-withdrawing groups, they may be the same or different from each other.

  Specific examples of the electron-withdrawing group of the electron-withdrawing specific aromatic compound used in the present invention include fluorine atom, chlorine atom, bromine atom, iodine atom, cyano group, aldehyde group, nitro group, nitroso group, acyl Group, alkoxycarbonyl group, aryloxycarbonyl group, aralkyloxycarbonyl group, alkoxysulfonyl group, alkoxysulfinyl group, alkylsulfonyloxy group, alkylsulfinyloxy group, fluoroalkyl group, carboxyamide group, sulfonamide group, carboxyimide group, Examples thereof include an azo group, an aryl group, a thioalkyl group, a carboxyl group, a sulfo group, a sulfino group, a sulfeno group, a phosphinico group, a phosphono group, a boronic acid group, and a boranoic acid group. Among these, from the viewpoint of stability and versatility of the electron withdrawing specific aromatic compound, fluorine atom, chlorine atom, cyano group, aldehyde group, nitro group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, aralkyloxycarbonyl group , A fluoroalkyl group, a carboxyl group, a sulfo group, and a boronic acid group are preferable, and more preferably a cyano group, a nitro group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an aralkyloxycarbonyl group, a carboxyl group, and a boronic acid group. And more preferably a cyano group, a nitro group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an aralkyloxycarbonyl group, or a carboxyl group.

  Since the molecular weight of the electron-withdrawing group part of the electron-withdrawing specific aromatic compound used in the present invention is too large, the molecular volume of the whole compound becomes large and it is difficult to incorporate into the phthalocyanine crystal. Preferably, it is 250 or less, more preferably 200 or less, still more preferably 150 or less.

  The electron-withdrawing specific aromatic compound used in the present invention can be classified into two parts, ie, an electron-withdrawing group portion and a portion other than the electron-withdrawing group (aromatic ring portion) from the viewpoint of its structure.

  The structure of the aromatic ring portion of the electron withdrawing specific aromatic compound used in the present invention is a structure having 4n + 2 (wherein n represents an integer of 0 or more) π electrons in a planar cyclic polyene, that is, Hückel. Any structure can be used as long as it has an aromatic property that satisfies the law, but if the structure of the aromatic ring portion is too large, there may be many adverse effects such as a decrease in solubility. In the formula 4n + 2, n is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less.

  Examples of the aromatic ring portion of the electron withdrawing specific aromatic compound used in the present invention include aromatic rings composed of hydrocarbons such as benzene, naphthalene, azulene, anthracene, phenanthrene, fluorene, pyrene, perylene, pyrrole, thiophene, Examples thereof include aromatic rings containing heteroatoms such as furan, silole, pyridine, indole, chroman, benzothiophene, benzofuran, quinoline, isoquinoline, carbazole, acridine, phenoxazine, and thianthrene. Among these aromatic rings, from the viewpoint of solubility in a non-acidic specific organic compound, an aromatic ring having 14 or less elements constituting the aromatic ring is preferable, and an aromatic ring having 10 or less elements is more preferable. An aromatic ring made of hydrocarbon is more preferred, and benzene and naphthalene are still more preferred.

  The molecular weight of the aromatic ring portion of the electron withdrawing specific aromatic compound used in the present invention is usually 1000 or less because it is difficult to incorporate the electron withdrawing specific aromatic compound into the phthalocyanine crystal if it is too large. , Preferably 500 or less, more preferably 300 or less, still more preferably 200 or less.

  The electron withdrawing specific aromatic compound used in the present invention may have a substituent other than the electron withdrawing group described above. Examples of the substituent that the electron-withdrawing specific aromatic compound may have other than the electron-withdrawing group include an alkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an aralkyloxy group, an alkenyl group, a phenolic hydroxyl group, Examples thereof include a substituted and unsubstituted amino group, and an alkyl group and an alkenyl group are preferable, and an alkyl group is more preferable because the effect of the present invention becomes difficult to obtain when the electron donating property becomes strong. Similar to the electron-withdrawing group, these substituents other than the electron-withdrawing group also increase the molecular volume of the entire electron-withdrawing specific aromatic compound if the molecular weight is too large, making it difficult to incorporate into the phthalocyanine crystal. The molecular weight is usually 300 or less, preferably 250 or less, more preferably 200 or less, and still more preferably 150 or less.

  Moreover, the electron withdrawing specific aromatic compound used in the present invention is solid under conditions of 1013 hPa (760 mmHg) and 25 ° C. A compound satisfying such conditions is preferred because it has a strong interaction with the phthalocyanine molecule.

  Examples of the structure of the electron withdrawing specific aromatic compound suitably used in the present invention are given below. However, the following structures are shown as examples only, and the structure of the electron-withdrawing specific aromatic compound that can be used in the present invention is not limited to the following examples. As long as it is not contrary to the gist of the present invention, an electron-withdrawing specific aromatic compound having an arbitrary structure can be used. In the structural formulas below, “Me” represents a methyl group, “Ph” represents a phenyl group, and “Bz” represents a benzoyl group.

  In addition, as an electron withdrawing specific aromatic compound, any 1 type may be used independently and 2 or more types may be used together by arbitrary combinations and a ratio.

(Non-acid specific organic compounds)
The non-acidic specific organic compound is an organic compound which is in a liquid state under conditions of 1013 hPa and 25 ° C. and does not have a functional group showing acidity. That is, the above <I-3-2. Among the non-acidic organic compounds described in the column of “crystal-type conversion compounds (B)>”, compounds in a liquid state under the conditions of 1013 hPa and 25 ° C. correspond to the non-acidic specific organic compounds.

  Here, the “functional group showing acidity” is a functional group that functions to show the acidity of the organic acid in the structure, and examples thereof include a carboxyl group, a thiocarboxyl group, a dithiocarboxyl group, a mercaptocarbonyl group, Hydroperoxy group, sulfo group, sulfino group, sulfenoic acid group, phenolic hydroxyl group, thiol group, phosphinico group, phosphono group, selenono group, selenino group, seleneno group, arsinico group, arsono group, boronic acid group, boranoic acid group, etc. Is mentioned. The non-acidic specific organic compound used in the present invention is an organic compound having no acid functional group.

  The non-acidic specific organic compound used in the present invention may have any structure, but from the viewpoint of crystal form controllability when it is brought into contact with the phthalocyanine crystal precursor, an unsubstituted amino acid is included in the structure. An organic compound having no group, one substituted amino group, and no alcoholic hydroxyl group is preferred.

  The non-acidic specific organic compounds used in the present invention can be roughly classified into aliphatic compounds and aromatic compounds (in the following description, these are appropriately referred to as “non-acidic specific aliphatic compounds” and “non- It shall be referred to as an acidic specific aromatic compound).

  Examples of non-acidic specific aliphatic compounds include saturated or unsaturated aliphatic hydrocarbon compounds such as pinene, terpyrenone, hexane, cyclohexane, octane, decane, 2-methylpentane, ligroin, petroleum benzine; diethyl ether, diisopropyl ether Aliphatic ether compounds such as dibutyl ether, dimethyl cellosolve, ethylene glycol dibutyl ether, tetrahydrofuran, 1,4-dioxane, 1,3-dioxolane; dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,2, Halogenated aliphatic compounds such as 2,2-tetrachloroethane; aliphatic ketone compounds such as methyl ethyl ketone, methyl isobutyl ketone, diisopropyl ketone, diisobutyl ketone, cyclohexanone and cyclopentanone; acetic acid Aliphatic ester compounds such as chill, propyl acetate, butyl acetate, isobutyl acetate, hexyl acetate, butyl acrylate, methyl propionate, cyclohexyl acetate; aliphatic alcohol compounds such as methanol, ethanol, butanol; normal propyl aldehyde, normal butyraldehyde And the like, and the like. In addition, the hydrocarbon skeleton possessed by these non-acidic specific aliphatic compounds may be either a chain (either linear or branched) or cyclic, and a chain and cyclic combination. It may be.

  On the other hand, examples of non-acidic specific aromatic compounds include aromatic hydrocarbon compounds such as toluene, xylene, naphthalene, biphenyl, terphenyl; monochlorobenzene, dichlorobenzene, trichlorobenzene, dichlorotoluene, chloronaphthalene, bromobenzene, etc. Halogenated aromatic compounds: aromatic nitro compounds such as nitrobenzene and fluoronitrobenzene, aromatic ester compounds such as methyl benzoate, butyl benzoate, methyl chlorobenzoate, methyl methylbenzoate, and phenyl acetate; diphenyl ether, anisole, chloroanisole Aromatic ether compounds such as benzaldehyde and chlorobenzaldehyde; aromatic ketone compounds such as acetophenone and chloroacetophenone; thiophene, furan, and Phosphorus, like heterocyclic aromatic compounds picoline.

  Among these non-acidic specific organic compounds, an aliphatic compound, an aromatic compound, or an aromatic hydrocarbon compound containing a halogen atom or an oxygen atom is preferable from the viewpoint of crystal form conversion ability. Among these, in consideration of the stability during dispersion of the obtained phthalocyanine crystal, a halogenated aliphatic compound, an aliphatic ether compound, an aliphatic ketone compound, an aliphatic ester compound, an aromatic hydrocarbon compound, a halogenated aromatic compound, Aromatic nitro compounds, aromatic ketone compounds, aromatic ester compounds, and aromatic aldehyde compounds are more preferable. From the viewpoint of the characteristics of electrophotographic photoreceptors using the obtained phthalocyanine crystals as materials, aliphatic ether compounds, halogenated compounds Aromatic compounds, aromatic nitro compounds, aromatic ketone compounds, aromatic ester compounds, or aromatic aldehyde compounds are more preferred.

  These non-acidic specific organic compounds may belong to a plurality of compound groups at the same time among the above-mentioned compound groups depending on the types of substituents in the structure (for example, nitrochlorobenzene is a “halogenated aromatic compound”). ”And“ aromatic nitro compounds ”), such non-alcoholic organic compounds are judged to have the attributes of all of the plurality of categories, and to determine the attributes of the compounds. (For example, nitrochlorobenzene has the attributes of both halogenated aromatics and aromatic nitro compounds).

  The non-acidic specific organic compound used in the present invention is in a liquid state under the conditions of 1013 hPa (760 mmHg) and 25 ° C.

  The molecular weight of the non-acidic specific organic compound is not particularly limited, but as the molecular weight increases, the viscosity and the like increase and the productivity decreases, so the molecular weight of the non-acidic specific organic compound is usually 1000 or less, preferably 500 or less, more preferably Is 400 or less, more preferably 300 or less. On the other hand, if the molecular weight of the non-acidic specific organic compound is too small, the boiling point is generally low, and since it tends to volatilize, the handling during production tends to decrease. Therefore, the lower limit of the molecular weight is usually 50 or more, preferably 100 That's it.

  In addition, as a non-acidic specific organic compound, any 1 type may be used independently and 2 or more types may be used together by arbitrary combinations and a ratio.

(Combination of electron-withdrawing specific aromatic compound and non-acidic specific organic compound)
It is not clear why the presence of electron-withdrawing specific aromatic compounds when changing the crystal form affects the characteristics of phthalocyanine crystals as electrophotographic photoreceptors. Presuming that the effect of the present invention can be obtained by coexisting the attracting specific aromatic compound and the electron attracting specific aromatic compound being more efficiently incorporated into the phthalocyanine crystal. Is done.

<I-3-4. Crystal-type conversion compounds (D)>
The compound for crystal type conversion (D) is an aromatic compound (a specific substituent-containing aromatic compound) having an oxygen atom-containing group and a halogen atom having an atomic weight of 30 or more as a substituent. This specific substituent-containing aromatic compound is used as a contact compound for crystal form conversion.

(Aromatic compounds containing specific substituents)
The specific substituent-containing aromatic compound refers to an aromatic compound having an oxygen atom-containing group and a halogen atom having an atomic weight of 30 or more as a substituent.

  Examples of the aromatic skeleton of the specific substituent-containing aromatic compound include aromatic hydrocarbon skeletons such as benzene, naphthalene, anthracene, phenanthrene, biphenyl, and terphenyl, and pyrrole, thiophene, furan, pyridine, quinoline, isoquinoline, phenanthroline, and the like. Heterocyclic aromatic skeletons can be mentioned. When the aromatic skeleton has a heteroatom such as nitrogen, oxygen or sulfur, the controllability to the above-mentioned specific crystal type which is a preferred crystal type in the phthalocyanine crystal of the present invention is achieved. An aromatic hydrocarbon skeleton is preferable because it decreases. The specific substituent-containing aromatic compound is preferably in a liquid state when brought into contact with the phthalocyanine crystal precursor, but since it is difficult to obtain a liquid state if the aromatic skeleton has a large molecular weight, it is usually benzene, naphthalene, biphenyl. , Pyrrole, thiophene, furan, pyridine and the like are used. Of these, aromatic hydrocarbon skeletons such as benzene, naphthalene, and biphenyl are preferable, and benzene is particularly preferable from the viewpoint of the characteristics of the electrophotographic photosensitive member of the phthalocyanine crystal.

  Further, since the contact between the specific substituent-containing aromatic compound and the phthalocyanine crystal precursor is usually performed at 100 ° C. or lower, the melting point of the specific substituent-containing aromatic compound is usually 100 ° C. or lower. If the melting point is too high, the handling property of the specific substituent-containing aromatic compound is lowered during the contact with the phthalocyanine crystal precursor. Therefore, the melting point of the specific substituent-containing aromatic compound is preferably 80 ° C. or less. Preferably it is 60 degrees C or less.

  Examples of the halogen atom having an atomic weight of 30 or more possessed by the specific substituent-containing aromatic compound include a chlorine atom, a bromine atom and an iodine atom. From the viewpoint of handling during production, a chlorine atom and a bromine atom are preferable, and an electrophotographic photoreceptor From the standpoint of the characteristics, a chlorine atom is more preferable.

  The halogen atom having an atomic weight of 30 or more possessed by the specific substituent-containing aromatic compound is usually directly bonded to the aromatic skeleton. The number of halogen atoms having an atomic weight of 30 or more is arbitrary, but as the number of halogen atoms increases, the freezing point increases and the handling at the time of production decreases. From the aspect, 2 or less is more preferable. Among these, a monohalogen-substituted aromatic compound is particularly preferable.

  The type of the group containing an oxygen atom that the specific substituent-containing aromatic compound has is not particularly limited, but examples include phenolic hydroxyl group; aldehyde group; carboxylic acid group; nitroso group; nitro group; imido acid group; Hydroxamic acid group; Cyanic acid group; Isocyanic acid group; Azoxy group; Amide group; Acyl group such as acetyl group and phenoxy group; Ether group such as methoxy group, benzyloxy group, and phenoxy group; Examples include acetal groups such as a methyl ethyl acetal group and an ethylene acetal group. Among these groups, for a group having a substituent that can be further substituted, such as an alkyl chain, the substituent may be further substituted.

  Among the groups containing oxygen atoms, from the viewpoint of crystal controllability, a substituent having a carbonyl group such as an aldehyde group, an ester group, an acyl group, and an acyloxy group, a nitro group, and an ether group are preferable. A group, an ether group, an ester group, an acyl group, and an acyloxy group are more preferable.

  The effect of the present invention is that the use of a specific substituent-containing aromatic compound increases the ability to control the crystal form at the time of contact with the phthalocyanine crystal precursor, and the specific substituent-containing aromatic compound is further contained in the phthalocyanine crystal. Therefore, the group containing an oxygen atom may be directly bonded to the aromatic ring and may be bonded to the aromatic ring via a divalent organic residue (excluding an arylene group). May be bonded to.

  When a group containing an oxygen atom is bonded to an aromatic ring via a divalent organic residue, the molecular volume of the aromatic compound containing the specific substituent is increased by the amount of the organic residue and incorporated into the phthalocyanine crystal. The molecular weight of the organic residue part is usually 100 or less, preferably 50 or less, because it is difficult to form. However, a group containing an oxygen atom does not have a divalent organic residue and is directly bonded to an aromatic ring via an oxygen atom like an ether group, or a carbon atom of a carbonyl group or a nitro group. More preferably, the atom directly bonded to the aromatic ring, such as a nitrogen atom, has an oxygen atom.

  The molecular weight per group containing oxygen atoms is usually 300 or less. If the molecular weight is too large, the characteristics of the electrophotographic photosensitive member are deteriorated, so 250 or less is preferable, 200 or less is more preferable, and 150 or less is even more preferable.

  Regarding the number of oxygen atom-containing groups that the specific substituent-containing aromatic compound has, if the molecular weight and molecular volume of the specific substituent-containing aromatic compound both increase, the specific substituent-containing aromatic compound should be used. Is less than 5, preferably less than 3, more preferably less than 2, and still more preferably 1.

  The specific substituent-containing aromatic compound may have other substituents on the aromatic ring in addition to a group containing an oxygen atom and a halogen atom having an atomic weight of 30 or less. Other substituents include alkyl groups such as methyl, ethyl, isopropyl and cyclohexyl groups; thioalkyl groups such as thiomethyl and thioethyl groups; cyano groups; mercapto groups; amino groups, monomethylamino groups and methylethylamino groups. A substituted or unsubstituted amino group such as a halogenated alkyl group such as a trifluoromethyl group; a substituent not containing a known oxygen atom such as a fluorine atom; a halogen atom having a molecular weight of 29 or less, and the like.

  Among the examples of other substituents described above, regarding a substituent having a carbon chain such as an alkyl group, a substituted amino group, and a halogenated alkyl group, the carbon chain portion has any structure of linear, branched, and cyclic. However, if the structure of the carbon chain portion of these substituents is too large, the stability of the resulting phthalocyanine crystal is adversely affected. Therefore, a linear or branched structure is preferable. More preferably, it is linear. Further, the carbon number of the carbon chain portion is usually 20 or less, but if the carbon number of the carbon chain portion is too large, the effect of the specific substituent-containing aromatic compound is reduced, and therefore preferably 15 or less, more preferably Is 10 or less, more preferably 6 or less.

  Among the examples of other substituents described above, a fluorine atom or an alkyl group is preferable in consideration of crystal controllability during crystal conversion. Among them, a methyl group, an ethyl group, and a fluorine atom are more preferable, and a methyl group or a fluorine atom is more preferable because the crystal controllability at the time of crystal conversion is reduced when the three-dimensional molecular volume as a substituent is increased.

In addition, the said specific substituent containing aromatic compound may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.
In addition, one or two or more specific substituent-containing aromatic compounds may be mixed with one or more other compounds and brought into contact with the phthalocyanine crystal precursor. In this case, the type of the other compound used in combination with the specific substituent-containing aromatic compound is not particularly limited as long as it does not undesirably affect the phthalocyanine crystal precursor to be used and the phthalocyanine crystal to be obtained. However, even when other compounds other than the specific substituent-containing aromatic compound are used in combination, the ratio of the specific substituent-containing aromatic compound to the total amount of the specific substituent-containing aromatic compound and the other compound is usually 50% by weight. Above all, the content is preferably 75% by weight or more.

  The amount of the specific substituent-containing aromatic compound used varies depending on the method used for the contact treatment, and cannot be specified unconditionally, but in general, it is generally 50% by weight or more, preferably in terms of the weight ratio to the phthalocyanine crystal precursor. Is in the range of 100% by weight or more, usually 2000% by weight or less, preferably 1000% by weight or less. In addition, when using together 2 or more types of specific substituent containing aromatic compounds, it is made for these total ratios to satisfy | fill the said range.

<I-3-5. Other>
In the crystal type conversion step, as described above, any one of the above-mentioned crystal type conversion compounds (A) to (D) may be used alone, and two or more types may be used in any combination and ratio. You may use together.

[I-4. (Crystal type conversion process)
In the crystal form conversion step, the crystal form of the phthalocyanine crystal precursor is converted using the above-described compounds for crystal form conversion. That is, the crystal form of the phthalocyanine crystal precursor is converted by bringing the phthalocyanine crystal precursor into contact with the crystal form conversion contact compounds in the presence of the crystal form conversion coexisting compounds used as necessary.

Here, in the crystal type conversion step, the method for bringing the phthalocyanine crystal precursor into contact with the contact compound for crystal type conversion is not particularly limited, and any known method may be used.
Among them, it is common to contact a phthalocyanine crystal precursor with a contact compound for crystal type conversion in the presence of water, which is suitable for obtaining the phthalocyanine crystal of the present invention.

  When water is used, the amount used is not particularly limited, but is usually 100% by weight or more, particularly 500% by weight or more, and usually 5000% by weight or less, especially 1500% by weight with respect to the contact compound for crystal form conversion. % Or less is preferable. In addition, when using together 2 or more types of contact compounds for crystal form conversion, it is preferable that those total weights satisfy the said range.

  As a specific method for contacting the phthalocyanine crystal precursor and the crystal-type conversion compound, for example, the phthalocyanine crystal precursor may be vapor or liquid containing the crystal-type conversion compound, or the crystal-type conversion compound. In which the phthalocyanine crystal precursor and the compound for crystal type conversion are brought into contact with a solution containing water, and an apparatus such as an automatic mortar, planetary mill, vibration ball mill, CF mill, roller mill, sand mill, kneader, etc. Among them, there is a method of contacting with media while applying physical force.

  The temperature at the time of contact between the phthalocyanine crystal precursor and the crystal-type conversion compound is not particularly limited, but is usually 150 ° C. or lower. Therefore, it is desirable that all of the crystal-type conversion contact compounds used in the present invention have a melting point of usually 150 ° C. or lower. When the melting point of the contact compound for crystal type conversion is too high, the handling property of the contact compound for crystal type conversion at the time of crystal conversion is lowered, so that it is preferably 120 ° C. or lower, more preferably 80 ° C. or lower.

  The phthalocyanine crystal of the present invention is obtained by contact treatment (ie, crystal type conversion treatment) between the phthalocyanine crystal precursor and the crystal type conversion compound. The obtained phthalocyanine crystal of the present invention may be washed with water, various organic solvents, or the like as necessary. The phthalocyanine crystal of the present invention obtained after the contact treatment or after washing is usually in a wet cake state. As described above, the effect of the present invention is obtained by incorporating the crystal-type conversion compounds into the phthalocyanine crystal when the phthalocyanine crystal precursor is brought into contact with the crystal-type conversion compounds during crystal conversion. Therefore, the content of the phthalocyanine in the wet cake of the phthalocyanine crystal of the present invention after the contact treatment or after washing (the weight of the phthalocyanine relative to the total weight of the wet cake) is not particularly limited, and any amount It may be.

  The wet cake of phthalocyanine crystals of the present invention obtained after the contact treatment or after washing is usually subjected to a drying step. The drying method can be dried by a known method such as blow drying, heat drying, vacuum drying or freeze drying.

  The phthalocyanine crystal of the present invention obtained by the above method usually takes a form in which primary particles aggregate to form secondary particles. The particle size varies greatly depending on the conditions and formulation at the time of contact between the phthalocyanine crystal precursor and the crystal-type conversion compound, but in consideration of dispersibility, the primary particle size is preferably 500 nm or less. From the viewpoint of properties, the thickness is preferably 250 nm or less.

  In the present invention, the definition of whether or not crystal conversion has been performed before and after the contact between the phthalocyanine crystal precursor and the crystal-type conversion compound is as follows. That is, when each peak of the powder X-ray diffraction spectrum is completely the same before and after the contact, it is defined that the crystal is not converted, and the peak position obtained from the powder X-ray diffraction spectrum before and after the contact, the presence / absence of the peak, If there is any difference in information such as price range, it is defined that the crystal has been transformed.

[I-5. Crystal form of phthalocyanine crystal]
The crystal form of the phthalocyanine crystal of the present invention may be any crystal form as long as it is different from that of the phthalocyanine crystal precursor, and in particular, an electrophotography when the phthalocyanine crystal is used as a material for an electrophotographic photosensitive member. From the viewpoint of the characteristics of the photoreceptor, a crystal form having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to CuKα characteristic X-ray (wavelength 1.541Å) (hereinafter referred to as “specific crystal form” as appropriate) .) Is preferred.

  Although the mechanism by which the effect of the present invention can be obtained has not been clarified, when the crystal form is converted by bringing the phthalocyanine crystal precursor into contact with the crystal form conversion compound, the phthalocyanine ring and the crystal form conversion compound are Crystalline conversion compounds having an interaction are incorporated into the phthalocyanine crystal, and the incorporated crystal conversion compounds interact with water as a sensitizer present in the crystal, thereby reducing the humidity. Suppresses desorption of water from the crystal under conditions, and allows water molecules to exist in the phthalocyanine crystal even under low-humidity conditions. It is thought that this is because the compound for crystal type conversion plays a role as a sensitizer instead of the water molecule as the sensitizer.

  Here, the above-mentioned specific crystal type has a lower crystal density than other crystal types, and there are many vacant spaces in the crystal. Therefore, the phthalocyanine crystal is brought into contact with the compound for converting the crystal type to obtain the above-mentioned crystal type. When the specific crystal form is constructed, it is considered that the compound for converting the crystal form is easily taken into the phthalocyanine crystal and plays a role as a sensitizer in the phthalocyanine crystal.

  Hereinafter, when the phthalocyanine crystal of the present invention has the above-mentioned specific crystal type, why the effect of the present invention is remarkably obtained, the mechanism that is presumed is divided for each type of compound for crystal type conversion, Consider more specifically.

  When the crystal form conversion compounds (A) are used, that is, when the phthalocyanine crystal precursor is brought into contact with the aromatic aldehyde compound to obtain the phthalocyanine crystal of the present invention, the phthalocyanine ring is used in constructing the crystal form. And the π electrons of the aromatic ring part of the aromatic aldehyde compound interact, the aromatic aldehyde compound is incorporated into the phthalocyanine crystal, and the aldehyde group part of the incorporated aromatic aldehyde compound is present in the crystal By interacting with water as a sensitizer, water desorption from the crystal under low humidity conditions is suppressed, and water molecules can exist in the phthalocyanine crystal even under low humidity conditions. Sensitive decrease due to desorption of water as a sensitizer is suppressed, or the aldehyde group of an aromatic aldehyde compound is a sensitizer. Considered or not to play a role as a sensitizer instead of water molecules.

  When the crystal form conversion compounds (B) are used, that is, when the phthalocyanine crystal precursor is brought into contact with a non-acidic organic compound in the presence of a specific organic acid compound to obtain the phthalocyanine crystal of the present invention, the crystal type When a specific organic acid compound is incorporated into a phthalocyanine crystal and the incorporated specific organic acid compound interacts with water as a sensitizer present in the crystal, Desorption of water from the crystal of water, and water molecules can exist in the phthalocyanine crystal even under low humidity conditions, thereby suppressing a decrease in sensitivity due to desorption of water as a sensitizer. For this reason, it is considered that the specific organic acid compound plays a role as a sensitizer instead of the water molecule as the sensitizer.

  When using the crystal-type conversion compounds (C), that is, when the phthalocyanine crystal precursor is brought into contact with a non-acidic specific organic compound in the presence of an electron-withdrawing specific aromatic compound to obtain the phthalocyanine crystal of the present invention. When the crystal form is constructed, the electron-withdrawing specific aromatic compound is incorporated into the phthalocyanine crystal, and the incorporated electron-withdrawing specific aromatic compound is mixed with water as a sensitizer present in the crystal. By interacting, water desorption from the crystal under low humidity conditions is suppressed, and water molecules can exist in the phthalocyanine crystal even under low humidity conditions. It may be because the sensitivity decrease due to desorption is suppressed, or because the electron-withdrawing specific aromatic compound plays a role as a sensitizer instead of the water molecule that is a sensitizer. It is.

  When the crystal-type conversion compounds (D) are used, that is, when the phthalocyanine crystal precursor is brought into contact with the specific substituent-containing aromatic compound to obtain the phthalocyanine crystal of the present invention, the above-mentioned specific substituent-containing aromatic is used. Since the compound has a halogen atom having an atomic weight of 30 or more, the compound has excellent crystal form controllability at the time of crystal conversion into a specific crystal form, and the phthalocyanine ring of the phthalocyanine crystal precursor and a specific substituent-containing aromatic group When the π-electrons of the aromatic ring portion of the compound interact with each other, the specific substituent-containing aromatic compound is incorporated into the phthalocyanine crystal at the time of crystal conversion, and contains the oxygen atom in the specific substituent-containing aromatic compound. It is thought that the group plays the role of a sensitizer in the crystal.

  For the above reasons, the phthalocyanine crystal of the present invention preferably has the above-mentioned specific crystal type.

When the phthalocyanine crystal of the present invention has the above-mentioned specific crystal type, the following (i) to (iii) are exemplified as a combination of clear peaks shown together with the peak at 27.2 °.
(I) 9.6 °, 24.1 °, 27.2 °
(Ii) 9.5 °, 9.7 °, 24.1 °, 27.2 °
(Iii) 9.0 °, 14.2 °, 23.9 °, 27.1 °

  Among them, among the combinations of the peaks (i) to (iii), those showing the combination of the peaks (i) or (ii) are preferable because of excellent crystal stability during dispersion.

  In particular, crystal forms having main diffraction peaks at 7.3 °, 9.6 °, 11.6 °, 14.2 °, 18.0 °, 24.1 ° and 27.2 °, or 7.3 A crystal type having main diffraction peaks at °, 9.5 °, 9.7 °, 11.6 °, 14.2 °, 18.0 °, 24.2 ° and 27.2 ° is an electrophotographic photoreceptor. From the standpoint of dark decay and residual potential when used as a material.

  Note that a phthalocyanine crystal having a peak near 26.2 ° or 28.6 ° rearranges to another crystal type at the time of dispersion, and causes a reduction in electrophotographic characteristics. Therefore, the phthalocyanine crystal of the present invention has 26.2 °. It is preferable that there is no clear peak around ° or 28.6 °.

  As described above, the effect of the compound for crystal type conversion in the phthalocyanine crystal of the present invention is that the compound for crystal type conversion is brought into contact with the phthalocyanine crystal precursor and the compound for crystal type conversion at the time of crystal conversion. Is considered to be obtained by being incorporated into the phthalocyanine crystal and is not dependent on the orientation of the molecules in the crystal. Therefore, in the preferred peak combinations listed above, the intensity ratio between the peaks is considered to have no correlation with the effect of the present invention. Therefore, these peaks may have any intensity ratio, but usually the peak near 27.2 ° or the peak near 9.6 ° is often the largest.

[I-6. (Chlorinated oxytitanium phthalocyanine)
In the case of an oxytitanium phthalocyanine crystal (a crystal or mixed crystal containing at least oxytitanium phthalocyanine) suitable as the phthalocyanine crystal of the present invention, an oxytitanium phthalocyanine (chlorinated) in which the phthalocyanine ring is chlorinated in the crystal due to a difference in production method. Oxytitanium phthalocyanine) may be contained. Since the effect of the present invention is considered to be manifested by the inclusion of the crystal-type conversion compounds in the phthalocyanine crystal, the oxytitanium phthalocyanine crystal is incorporated so that a large amount of the crystal-type conversion compounds are incorporated. It is preferable that there is a lot of space inside. Chlorinated oxytitanium phthalocyanine has a chloro group in the phthalocyanine ring portion, and its molecular volume is larger than that of unsubstituted oxytitanium phthalocyanine. For this reason, when chlorinated oxytitanium phthalocyanine is present in the crystal, the space for taking in the compound for converting the crystal form is reduced. For the above reasons, oxytitanium phthalocyanines (hereinafter referred to as “oxytitanium phthalocyanine crystal precursors”) used as phthalocyanine crystal precursors for the production of oxytitanium phthalocyanine crystals have a chlorinated oxytitanium phthalocyanine content. Less is preferable.

  The content of chlorinated oxytitanium phthalocyanine in the oxytitanium phthalocyanine crystal precursor can be measured by any conventionally known analysis method. For example, the elemental analysis method described in JP-A-2001-115054 and It can be determined by mass spectrum measurement. Specific conditions for elemental analysis and mass spectrum measurement include the following conditions, for example.

<Chlorine content measurement conditions (elemental analysis)>
100 mg of oxytitanium phthalocyanine crystal precursor is precisely weighed and placed on a quartz board, and completely burned in a temperature rising electric furnace (for example, QF-02 manufactured by Mitsubishi Chemical Corporation), and the combustion gas is determined in 15 ml of water. Absorb. The obtained absorbing solution is diluted to 50 ml and subjected to chlorine analysis by ion chromatography (“DX-120” manufactured by Dionex). The ion chromatography conditions are shown below.

Column: Dionex IonPak AG12A + AS12A
Eluent: 2.7 mM sodium carbonate (Na ₂ CO ₃ ) /0.3 mM sodium bicarbonate (NaHCO ₃ )
Flow rate: 1.3ml / min
Injection volume: 50 μl

<Mass spectrum measurement conditions>
(A) Sample preparation:
0.50 g of oxytitanium phthalocyanine crystal precursor is placed in a 50 ml glass container together with 30 g of glass beads (φ1.0 to 1.4 mm) and 10 g of cyclohexanone, and dispersed for 3 hours with a dye dispersion tester (paint shaker). A 5% by weight oxytitanium phthalocyanine dispersion is obtained. 1 μl of this 5 wt% oxytitanium phthalocyanine dispersion is collected in a 20 ml sample bottle, 5 ml of chloroform is added, and the mixture is dispersed by ultrasonic waves for 1 hour to prepare a 10 ppm oxytitanium phthalocyanine dispersion.

(B) Measuring equipment and conditions:
Measuring device: JMS-700 / MStaion made by JEOL
Ionization mode: DCI (-)
Reaction gas: isobutane (ionization chamber pressure 1 × 10 ⁻⁵ Torr)
Filament rate: 0-> 0.90A (1A / min)
Mass spectrometry: 2000
Scanning method: MF-Linear
Scan mass range: 500 to 600
Total mass range scan time: 0.8 sec
Repeat time: 0.5 sec

(C) Calculation method of mass spectral peak intensity ratio between chlorinated oxytitanium phthalocyanine and unsubstituted oxytitanium phthalocyanine:
1 μl of 10 ppm oxytitanium phthalocyanine dispersion prepared in the above procedure is applied to the filament of the DCI probe, and mass spectrum measurement is performed under the above conditions. In the obtained mass spectrum, peak areas 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. The ratio (“610” peak area / “576” peak area) is calculated as the mass spectrum peak intensity ratio.

  The amount of chlorinated oxytitanium phthalocyanine contained in the oxytitanium phthalocyanine crystal precursor obtained by measurement based on the above <chlorine content measurement conditions (elemental analysis)> is preferably 0.4% by weight or less. Preferably it is 0.3 weight% or less, More preferably, it is 0.2 weight% or less.

  Moreover, the mass spectrum peak intensity ratio between chlorinated oxytitanium phthalocyanine and unsubstituted oxytitanium phthalocyanine in the oxytitanium phthalocyanine crystal precursor obtained by measurement based on the above <mass spectrum measurement conditions> is preferably 0.050. Hereinafter, it is more preferably 0.040 or less, and still more preferably 0.030 or less.

[I-7. Others]
Although the mechanism by which the use of the compound for crystal type conversion in the present invention affects the characteristics of the phthalocyanine crystal as an electrophotographic photosensitive member is not clear, as described above, the compound for crystal type conversion is a phthalocyanine at the time of crystal conversion. It is considered that the effect of the present invention is obtained by being incorporated into the crystal.

  The amount of the contact compound for crystal form conversion incorporated in the crystal varies depending on the production method and is not particularly limited, but is usually 0.1 part by weight or more with respect to 100 parts by weight of the phthalocyanine crystal. Especially, since the effect of this invention will decrease if there is little uptake | capture amount of the contact compounds for crystal form conversion, 0.2 weight part or more is preferable, More preferably, it is 0.3 weight part or more. However, since the stability of the phthalocyanine crystal decreases when the amount of the contact compound for converting the crystal form is excessive, it is preferably 10 parts by weight or less, more preferably 7 parts by weight or less. In addition, when multiple types of contact compounds for crystal type conversion exist in a phthalocyanine crystal, it is preferable that the total amount becomes the said range.

  The content of the contact compound for crystal form conversion in the phthalocyanine crystal can be calculated by measuring according to a known thermogravimetric analysis method. In particular, it is known that a phthalocyanine crystal having the above-described specific crystal type undergoes crystal rearrangement at around 220 to 270 ° C., and a compound contained in the crystal is released during this crystal rearrangement. Therefore, in the thermogravimetric analysis of the phthalocyanine crystal having the specific crystal form described above, the amount of the contact compound for crystal form conversion contained from the weight difference before and after crystal dislocation (for example, the weight difference between 200 ° C and 300 ° C). Can be calculated.

[II. Electrophotographic photoreceptor]
The electrophotographic photosensitive member of the present invention (hereinafter sometimes abbreviated as “photosensitive member of the present invention”) is a photosensitive member having a photosensitive layer on a conductive support, and the following definition (1) and definition: Of (2), at least one of the rules is satisfied.

-Definition (1): The film thickness of the photosensitive layer is within a specific range, and the value of the half-exposure amount and the fluctuation of the light attenuation characteristic due to the change in humidity satisfy the specific range.
Definition (2): The photosensitive layer contains the phthalocyanine crystal of the present invention.
The photoreceptor of the present invention may satisfy only one of the regulations (1) and (2), but satisfies both the regulations (1) and (2). preferable.

In the following description, first, focusing on the characteristics of the photoreceptor, the photoreceptor of the present invention that satisfies the definition (1) (hereinafter referred to as “specific property photoreceptor” as appropriate) will be described, and then electrophotography will be described. Focusing mainly on the configuration of the photoconductor, the photoconductor of the present invention that satisfies the definition (2) (hereinafter referred to as “specific configuration photoconductor” as appropriate) will be described. Further, when there is no particular distinction between the “specific characteristic photoconductor” and the “specific configuration photoconductor”, they are collectively referred to as “the photoconductor of the invention”.
Note that the terms “specific characteristic photoconductor” and “specific configuration photoconductor” are used only for convenience of explanation, and do not affect the present invention.

[II-1. Characteristics of photoconductor
The photoconductor having the specific characteristics of the present invention satisfies the above-mentioned definition (1), that is, the value of half-exposure E _1/2 described later, and the fluctuation of the light attenuation characteristic due to the change in humidity is the film thickness of the photoconductive layer. The photosensitive members are within a predetermined range.
This characteristic indicates that the specific characteristic photoconductor of the present invention has a small half-exposure amount E _1/2 and high sensitivity, and that the fluctuation of the light attenuation characteristic due to humidity change is extremely small.

The smaller the half-exposure amount E _1/2 of the photoconductor, the smaller the amount of exposure light energy in an image forming apparatus such as a printer or a copying machine. For example, the power consumption of a light source can be reduced. Therefore, it is preferable.

  Since the photoreceptor usually has a different capacitance depending on the film thickness of the photosensitive layer, the amount of surface charge differs even at the same potential when the film thickness of the photosensitive layer is different. That is, the sensitivity of the photoreceptor varies when the quantum efficiency is 1 depending on the film thickness of the photosensitive layer.

In the present invention, although the technical idea that the variation in light attenuation characteristics due to humidity is extremely small at the same time as the half exposure amount is small and the sensitivity is high, for the above reasons, the film thickness of the photosensitive layer is classified, In consideration of the sensitivity when the quantum efficiency is 1, the degree of fluctuation of the light attenuation characteristic due to the half exposure amount E _1/2 and the humidity is specified. Thus, it is possible to define a photoconductor that has particularly suitable characteristics for the image forming apparatus in accordance with the film thickness of the photosensitive layer.

Specifically, the half-exposure amount E _1/2 of the specific characteristic photoreceptor of the present invention is defined separately for each range of film thickness of the photosensitive layer as follows.

In the case of a photoreceptor having a photosensitive layer thickness of 35 ± 2.5 μm, the half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh is usually 0.059 or less, preferably 0.054 or less. More preferably, it is 0.051 or less, More preferably, it is 0.049 or less.

In the case of a photoreceptor having a photosensitive layer thickness of 30 ± 2.5 μm, the half exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh is usually 0.061 or less, preferably 0.056 or less. Preferably it is 0.053 or less, More preferably, it is 0.051 or less.

In the case of a photoconductor having a photosensitive layer thickness of 25 ± 2.5 μm, the half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh is usually 0.066 or less, preferably 0.061 or less. Preferably it is 0.058 or less, More preferably, it is 0.055 or less.

When the photosensitive layer has a thickness of 20 ± 2.5 μm, the half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh is usually 0.079 or less, preferably 0.073 or less. Preferably it is 0.069 or less, More preferably, it is 0.066 or less.

In the case of a photoreceptor having a photosensitive layer thickness of 15 ± 2.5 μm, the half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh is usually 0.090 or less, preferably 0.083 or less. Preferably it is 0.079 or less, More preferably, it is 0.075 or less.

However, in the present invention, the exposure amount (μJ / cm ² ) of light having a wavelength of 780 nm required to attenuate the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V is reduced by half. It is defined as the exposure amount E1 _{/ 2} . Method of measuring the half decay exposure E _1/2 will be described later in the section <Measurement method of half decay exposure E _1/2>.

In the present invention, the “film thickness” of the photosensitive layer refers to the total film thickness of the charge generation layer and the charge transport layer in the case of a laminated type photoreceptor, and the photosensitive layer in the case of a single layer type photoreceptor. It shall refer to the film thickness.
In addition, when a surface protective layer exists on a photosensitive layer, the film thickness including a surface protective layer shall be the film thickness of a photosensitive layer.
On the other hand, when a layer (for example, an intermediate layer) other than the charge generation layer, the charge transport layer, the single-layer type photosensitive layer, and the surface protective layer is present, the thickness of the layer is not included in the thickness of the photosensitive layer. .

  The film thickness of the photosensitive layer can be measured by various methods. For example, it can be measured using Surfcom 570A manufactured by Tokyo Seimitsu Co., Ltd.

  On the other hand, the smaller the fluctuation of the light attenuation characteristics due to the humidity change of the photoconductor, the smaller the photoconductor can be printed per unit time when the photoconductor is used in a process cartridge or an image forming apparatus, and the consumption. Power consumption is low, and image defects due to environmental fluctuations can be reduced.

Specifically, the fluctuation of the light attenuation characteristic due to the humidity change of the specific characteristic photoreceptor of the present invention is defined as follows.
That is, when the specific characteristic photoconductor of the present invention compares the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the exposure amount is halved. In the range from 0 to 10 times the exposure amount E _1/2 , the absolute value of the difference in surface potential at the same exposure amount (hereinafter referred to as “environmental variation dependent amount” as appropriate. The measuring method is <environmental variation dependent amount>). However, it is usually 50 V or less, preferably 40 V or less, more preferably 35 V or less, still more preferably 30 V or less, and particularly preferably 20 V or less.
The smaller the amount of photoconductor dependency on the environment, the smaller the image degradation that results from the environment change.

In the present invention, the measurement environment for the half-exposure dose E _1/2 and the light attenuation curve is defined by its temperature and humidity, but it is desirable that these measurements be performed in an environment with as little error as possible. .
Specifically, if the temperature is within a range of ± 2 ° C. of the temperature defined in the present invention, it is determined that the temperature corresponds to the temperature defined in the present invention.
Further, when the humidity is expressed in relative humidity, if it is within a range of ± 5% of the humidity defined in the present invention, it is determined that the humidity corresponds to the humidity defined in the present invention.

  There are no restrictions on the method of measuring temperature and relative humidity, but the measurement is usually performed by a method based on a method standardized by Japanese Industrial Standards (JIS). For temperature, the measurement method is specified in JIS Z8704, Z8705, Z8707, and for humidity, the measurement method is specified in JIS Z8806.

<Method for measuring half exposure E _1/2 >
In the present invention, the half exposure amount E _1/2 is a value measured by a static method using a commercially available photoconductor evaluation apparatus (Cynthia 55, manufactured by Gentec Corporation). Specifically, it is calculated | required by the procedure demonstrated below.

  The charger is placed at an angle of 0 °, the exposure device and the surface potential meter probe at 90 °, and the charge eliminator at an angle of 270 ° so that the distance from the photoreceptor surface to the charger, the surface potential meter probe and the charge remover is 2 mm. To place.

First, the surface of the photoconductor is charged at a constant rotational speed (30 rpm) on a scorotron charger set so that discharge is performed so that the surface potential of the photoconductor becomes about −700 V in a dark place. When the charged photoreceptor surface reaches the probe position, the surface is stopped, and 2.5 seconds after the stop, the 780 nm monochromatic light with an intensity of 0.15 μW / cm ² obtained from the attached spectral light source system POLAS 34 is used. Irradiate for 5 seconds. At this time, the exposure amount required until the surface potential of the photoconductor is changed from −550V to −275V is measured. The photosensitive member is rotated again, and the entire operation is performed by the static eliminator, and then the same operation is performed. This cycle is repeated 6 times, and the measured values of the exposure dose of 5 times except the first are averaged, and the obtained average value is defined as a half exposure dose E _1/2 (μJ / cm ² ).
In the above description, the case of the negatively charged type photoconductor is described as an example.

The half-exposure amount E _1/2 is measured in the same environment after leaving the photoconductor to be measured in an environment of temperature 25 ° C. ± 2 ° C. and humidity 50% ± 5% for 5 hours or more. .

<Measurement method of environmental variation dependency>
The environmental variation dependency amount in the present invention is an electrophotographic characteristic evaluation apparatus produced according to the standard of the Electrophotographic Society ["Basics and Applications of Secondary Electrophotographic Technology", (Electrophotographic Society, edited by Corona, pages 404-405) )] Is mounted, and electrical characteristics are evaluated by a cycle of charging, exposure, potential measurement, and static elimination. Specifically, it is calculated | required by the procedure demonstrated below.

  The charger is arranged at -70 °, the exposure device at 0 °, the surface electrometer probe at 36 °, and the static eliminator at an angle of -150 °, and each device is arranged at a distance of 2 mm from the photoreceptor surface. A scorotron charger is used for charging. The exposure lamp is a monochromatic light of 780 nm using a halogen lamp JDR110V-85WLN / K7 manufactured by USHIO INC. And a filter MX0780 manufactured by Asahi Spectroscopic Co., Ltd. 660 nm LED light is used for the charge removal light.

While rotating the photoconductor at a constant rotation speed (60 rpm), the absolute value of the initial surface potential of the photoconductor becomes 700 V (+700 V for a positively charged photoconductor, -700 V for a negatively charged photoconductor). The charged surface of the photosensitive member passes through an exposure portion where monochromatic light of 780 nm is exposed, and the surface potential is measured when the surface of the surface potential meter reaches the probe position (100 ms between exposure and potential measurement). . A single color light of 780 nm is passed through an ND filter to change the amount of light, and the exposure amount is irradiated with light in the range of 0 to 10 times the half exposure amount E _1/2 , and the surface potential at each exposure amount is measured. . This operation is performed in an environment having a temperature of 25 ° C. ± 2 ° C. and a relative humidity of 50% rh ± 5% (hereinafter also referred to as “NN environment” where appropriate). It may be sometimes referred to as “V _NN ”).

Thereafter, the same operation is performed in an environment of temperature 25 ° C. ± 2 ° C. and relative humidity 10% rh ± 5% (hereinafter sometimes referred to as “NL environment” as appropriate), and the post-exposure potential in the NL environment at each exposure dose. (Hereinafter sometimes referred to as “V _NL ” as appropriate) is measured.

Absolute value of the difference between the potential after exposure V _NL at potential V _NN and NL environment after exposure under NN environment at the same exposure (| V _NN -V _NL |) is calculated, and environmental change the maximum value Dependent amount.

  When measuring the post-exposure potential in an NN environment and an NL environment, the photoconductor to be measured is set to the NN environment (temperature 25 ° C. ± 2 ° C., relative humidity 50% rh ± 5%) and NL, respectively. It is carried out after standing for 5 hours or more in an environment (temperature 25 ° C. ± 2 ° C., relative humidity 10% rh ± 5%).

<Measurement method of sensitivity retention>
In the present invention, the sensitivity retention rate (hereinafter, simply referred to as “sensitivity retention rate”) due to a change in humidity of the photosensitive member is the same as the measurement device conditions using the same measurement device as the measurement method of the environmental variation dependency amount. In the above, the electrical characteristics are evaluated by the cycle of charging, exposure, potential measurement and static elimination according to the following procedure.

  While rotating the photoconductor at a constant rotation speed (60 rpm), the absolute value of the initial surface potential of the photoconductor becomes 700 V (+700 V for a positively charged photoconductor, -700 V for a negatively charged photoconductor). The charged surface of the photosensitive member passes through an exposure portion where monochromatic light of 780 nm is exposed, and the surface potential is measured when the surface of the surface potential meter reaches the probe position (100 ms between exposure and potential measurement). . Irradiate 780 nm monochromatic light through an ND filter while changing the amount of light, and the surface potential has an initial surface potential of 350 V (+350 V for positively charged photoconductors, − for negatively charged photoconductors). The irradiation energy (exposure energy) at 350 V) is measured.

A value (unit μJ / cm ² ) measured for irradiation energy (exposure energy) in an NN environment was defined as standard humidity sensitivity (hereinafter sometimes referred to as “En _1/2 ” as appropriate), and measured in an NL environment. The value (unit: μJ / cm ² ) is defined as low humidity sensitivity (hereinafter sometimes referred to as “El _1/2 ” as appropriate).

  As in the case of the method for measuring the environmental variation dependence amount, when measuring the post-exposure potential in the NN environment and the NL environment, the photoconductor to be measured is placed in the NN environment and the NL environment, respectively. After leaving for more than an hour.

Using the values of the standard humidity sensitivity En _1/2 and the low humidity sensitivity El _1/2 obtained, the sensitivity retention rate due to a change in humidity is calculated (unit%) by calculating according to the following formula.

  In particular, an oxytitanium phthalocyanine crystal having the above-mentioned specific crystal type (crystal type showing a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to CuKα characteristic X-ray (wavelength 1.541Å)) is sensitized. When changing the photoconductor contained in the layer from the NN environment (room temperature and normal humidity environment) to the NL environment (room temperature and low humidity environment), it takes time for water present in the crystals to desorb. When evaluating the environmental dependence of the characteristics, it is allowed to stand for at least 5 hours in an environment where the measurement is performed before the potential measurement.

  If the charge mobility due to the charge transport material is slow, the time from exposure to measurement is appropriately increased so that the change in surface potential with respect to the change in time required for measurement after exposure is sufficiently small. Is preferred.

[II-2. Configuration of photoconductor]
The specific constitution photoreceptor of the present invention is a photoreceptor having a photosensitive layer on a conductive support and satisfying the above-mentioned definition (2), that is, the photosensitive layer containing the phthalocyanine crystal of the present invention in the photosensitive layer.
The photosensitive layer of the photoconductor of the specific constitution of the present invention may contain only one kind of the phthalocyanine crystal of the present invention alone, but may contain two or more kinds in any combination and ratio.

The phthalocyanine crystal of the present invention normally functions as a charge generating substance.
The photosensitive layer of the specific constitution photoreceptor of the present invention may contain only the phthalocyanine crystal of the present invention as a charge generation material, but also contains one or more other charge generation materials. Also good.

Hereinafter, the structure of the photoreceptor of the present invention will be described in detail.
The specific configuration photoconductor has the same configuration as the above-described specific characteristic photoconductor except that the above-mentioned definition (2) is essential.
Therefore, in the following description, basically, the configuration of the photoconductor of the specific configuration and the configuration of the photoconductor of the specific characteristics will be collectively described as the configuration of the photoconductor of the present invention without particularly distinguishing, and the differences in configuration will be described. Appendices shall be added as appropriate.

<II-2-1. Conductive support>
As the conductive support, for example, a metal material such as aluminum, aluminum alloy, stainless steel, copper, nickel, or a resin material imparted with conductivity by adding conductive powder such as metal, carbon, tin oxide, Mainly used are resin, glass, paper, or the like obtained by depositing or coating a conductive material such as aluminum, nickel, ITO (indium tin oxide) on the surface. As the shape, a drum shape, a sheet shape, a belt shape or the like is used. Alternatively, a conductive support made of a metal material may be used in which a conductive material having an appropriate resistance value is applied for the purpose of controlling conductivity, surface properties, etc., or for covering defects.

  The surface of the conductive support 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. In particular, when using a non-cutting aluminum substrate such as drawing, impact processing, ironing, etc., it is preferable because the treatment eliminates dirt, foreign matter, and other foreign matters, small scratches, etc., and a uniform and clean substrate can be obtained. .

Moreover, when using metal materials, such as an aluminum alloy, as an electroconductive support body, you may use, after giving an anodic oxide film. Anodized film is formed, for example, 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.

  If the average thickness of the anodic oxide coating is too thick, strong sealing conditions are required due to high 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 easily generated 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.

  When an anodized film is formed, it is preferable to perform a sealing treatment. The sealing treatment may be performed by a normal method, for example, a low-temperature sealing treatment in which the sealing material is immersed in an aqueous solution containing nickel fluoride as a main component, or a high-temperature sealing in which the sealing treatment is immersed in an aqueous solution containing nickel acetate as a main component. It is preferable to apply a hole treatment.

  In the case of low-temperature sealing treatment, the concentration of the nickel fluoride aqueous solution to be used can be selected as appropriate, but more preferable results are obtained when the concentration is in the range of 3 to 6 g / l. The pH of the aqueous nickel fluoride solution is usually 4.5 or higher, preferably 5.5 or higher, and usually 6.5 or lower, preferably 6.0 or lower. As the pH adjuster, oxalic acid, boric acid, formic acid, acetic acid, sodium hydroxide, sodium acetate, aqueous ammonia and the like can be used. In order to further improve the physical properties of the film, cobalt fluoride, cobalt acetate, nickel sulfate, a surfactant and the like may be added to the nickel fluoride aqueous solution. The treatment temperature is usually in the range of 25 ° C. or higher, preferably 30 ° C. or higher, and usually 40 ° C. or lower, preferably 35 ° C. or lower, in order to facilitate the sealing treatment. The treatment time is preferably in the range of 1 to 3 minutes per 1 μm of film thickness. Subsequently, it is washed with water and dried to finish the low temperature sealing treatment.

  In the case of high-temperature sealing treatment, as the sealing agent, an aqueous metal salt solution such as nickel acetate, cobalt acetate, lead acetate, nickel acetate-cobalt, and barium nitrate can be used, and nickel acetate is particularly preferable. When using nickel acetate aqueous solution, it is preferable to use the density | concentration within the range of 5-20 g / l normally. It is preferable to treat the nickel acetate aqueous solution usually at a pH in the range of 5.0 to 6.0. As the pH regulator, aqueous ammonia, sodium acetate, or the like can be used. In order to improve the physical properties of the coating film, sodium acetate, organic carboxylic acid, anionic or nonionic surfactant may be added to the nickel acetate aqueous solution. The treatment temperature is usually in the range of 80 ° C. or higher, usually 100 ° C. or lower, preferably 90 ° C. or higher, and preferably 98 ° C. or lower. The treatment time is usually 10 minutes or longer, preferably 20 minutes or longer. Subsequently, it is washed with water and dried to finish the high temperature sealing treatment.

<II-2-2. Undercoat layer>
An undercoat layer may be provided between the conductive support and the photosensitive layer described later for improving adhesion and blocking properties. As the undercoat layer, a binder resin, a binder resin in which particles such as metal oxide are dispersed, and the like are used.

  Examples of the 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, Examples thereof include metal oxide particles containing a plurality of metal elements such as strontium titanate and barium titanate. Any one of these metal oxide particles may be used alone, or a plurality of these metal oxide particles may be mixed and used in an arbitrary combination and ratio. Among these metal 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 silicone. As the crystal form of the titanium oxide particles, any of rutile, anatase, brookite, and amorphous can be used. Moreover, the thing of a several crystal state may contain.

  Various particle sizes can be used as the particle size of the metal oxide particles. Among these, from the viewpoint of characteristics and liquid stability, the average primary particle size is usually 10 nm or more, usually 100 nm or less, particularly 50 nm or less. Those are preferred.

  The undercoat layer is preferably formed in a form in which the 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, may be a known binder resin such as a silane coupling agent. These can be used alone or in a cured form together with a curing agent. Among these, alcohol-soluble copolymerized polyamide, modified polyamide, and the like are preferable because they exhibit good dispersibility and coatability.

  The use ratio of the metal oxide particles with respect to the binder resin can be arbitrarily selected, but from the viewpoint of the stability of the dispersion and the coating property, it is usually used in the range of 10% by weight to 500% by weight. preferable.

  In addition, the undercoat layer may contain pigment particles, resin particles, and the like for the purpose of preventing image defects.

  The thickness of the undercoat layer can be arbitrarily selected, but it is usually 0.01 μm or more, particularly 0.1 μm or more, and usually 30 μm or less, especially 20 μm or less in view of the photoreceptor characteristics and coating properties. Is preferred.

<II-2-3. Photosensitive layer>
A photosensitive layer is formed on the conductive support (on the undercoat layer when an undercoat layer is provided). The photosensitive layer includes a charge generation material, a charge transport material, and a binder resin.

  As the structure of the photosensitive layer, a charge generation material and a charge transport material are dispersed in a binder resin and exist in the same layer (hereinafter referred to as “single layer type photosensitive layer” as appropriate), and charge generation. A photosensitive layer having a laminated structure in which a substance is dispersed into a charge generation layer in which a substance is dispersed in a binder resin and a charge transport layer in which a charge transport substance is dispersed in a binder resin (hereinafter, referred to as “laminated photosensitive layer” as appropriate). Any of these can be used. In the case of a laminated type photosensitive layer, a layered photosensitive layer is laminated in the order of a charge generation layer and a charge transport layer from the conductive support side, and a charge transport layer and a charge generation layer are laminated in this order from the side of the conductive support. Although it is divided into a reverse lamination type photosensitive layer, any of them can be applied. Hereinafter, each structure will be described.

(Charge generation layer of laminated photosensitive layer)
The charge generation layer of the multilayer photosensitive layer is prepared by dissolving or dispersing a binder resin in a solvent or dispersion medium and dispersing a charge generation material to prepare a coating solution. By coating and forming a film on the body (on the undercoat layer when an undercoat layer is provided) or on the charge transport layer in the case of a reverse laminated type photoreceptor, and binding fine particles of the charge generating material with a binder resin It is formed.

・ Charge generating materials:
In the case of a specific configuration photoconductor, at least the phthalocyanine crystal of the present invention is used as the charge generating material. In the case of a specific characteristic photoreceptor, at least the phthalocyanine crystal of the present invention is usually used as a charge generating substance.
Any one kind of the phthalocyanine crystals of the present invention may be used alone, but two or more kinds may be used in any combination and ratio. Further, only the phthalocyanine crystal of the present invention may be used as a charge generation material, but the phthalocyanine crystal of the present invention may be combined with other charge generation materials and used in a mixed state.

  It is preferable that the particle diameter of the phthalocyanine crystal of the present invention used as a charge generating substance is sufficiently small. Specifically, it is preferably 1 μm or less, more preferably 0.5 μm or less.

  Examples of other charge generation materials used in a mixed state with the phthalocyanine crystal of the present invention include various known dyes and pigments. Examples of dyes include phthalocyanine pigments, azo pigments, dithioketopyrrolopyrrole pigments, squalene (squarylium pigment), quinacridone pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, anthanthrone pigments, benzimidazole pigments, and the like. . Of these, phthalocyanine pigments and azo pigments are preferably used from the viewpoint of photosensitivity. In addition, any one kind of other charge generation materials may be used alone, or two or more kinds may be used in combination with any composition and combination.

・ Binder resin:
The type of the binder resin in the charge generation layer is not particularly limited. Examples thereof include polyvinyl butyral resin, polyvinyl formal resin, polyvinyl such as partially acetalized polyvinyl butyral resin in which a part of butyral is modified with formal or acetal. Acetal resin, polyarylate resin, polycarbonate resin, polyester resin, modified ether polyester resin, phenoxy resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl acetate resin, polystyrene resin, acrylic resin, methacrylic resin, polyacrylamide resin , Polyamide resin, polyvinyl pyridine resin, cellulosic resin, polyurethane resin, epoxy resin, silicone resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, casein, salt Vinyl chloride-vinyl acetate copolymer such as vinyl-vinyl acetate copolymer, hydroxy-modified vinyl chloride-vinyl acetate copolymer, carboxyl-modified vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer Copolymers, styrene-butadiene copolymers, vinylidene chloride-acrylonitrile copolymers, styrene-alkyd resins, silicone-alkyd resins, insulating resins such as phenol-formaldehyde resins, poly-N-vinylcarbazole, polyvinylanthracene, It can be selected from organic photoconductive polymers such as polyvinyl perylene, but is not limited to these polymers. In addition, any one of these binder resins may be used alone, or two or more of these binder resins may be mixed and used in an arbitrary combination and ratio.

・ Combination ratio:
The compounding ratio (weight) of the binder resin and the charge generation material in the charge generation layer is usually 10 parts by weight or more, preferably 30 parts by weight or more, and usually 1000 parts by weight, based on the ratio of the charge generation material to 100 parts by weight of the binder resin. The range is not more than parts by weight, preferably not more than 500 parts by weight. If the ratio of the charge generation material is too high, the stability of the coating solution may be reduced due to problems such as aggregation of the charge generation material. On the other hand, if it is too low, the sensitivity of the photoreceptor may be reduced. Therefore, it is preferable to use within the above range.

・ Solvent or dispersion medium:
Examples of the solvent or dispersion medium used for preparing the coating liquid include saturated aliphatic solvents such as pentane, hexane, octane, and nonane; aromatic solvents such as toluene, xylene, and anisole; chlorobenzene, dichlorobenzene, and chloronaphthalene. Halogenated aromatic solvents such as amide solvents such as dimethylformamide and N-methyl-2-pyrrolidone; alcohol solvents such as methanol, ethanol, isopropanol, n-butanol and benzyl alcohol; fats such as glycerin and polyethylene glycol Aliphatic polyhydric alcohols; chain and cyclic ketone solvents such as acetone, cyclohexanone, methyl ethyl ketone, 4-methoxy-4-methyl-2-pentanone; ester solvents such as methyl formate, ethyl acetate, n-butyl acetate; Methylene, chloroform Halogenated hydrocarbon solvents such as 1,2-dichloroethane; chain and cyclic ether solvents such as diethyl ether, dimethoxyethane, tetrahydrofuran, 1,4-dioxane, methyl cellosolve, ethyl cellosolve; acetonitrile, dimethyl sulfoxide , Sulfolane, aprotic polar solvents such as hexamethylphosphate triamide; nitrogen-containing compounds such as n-butylamine, isopropanolamine, diethylamine, triethanolamine, ethylenediamine, triethylenediamine, triethylamine; mineral oil such as ligroin; And those which do not dissolve the undercoat layer described above are preferably used. Any one of these solvents or dispersion media may be used alone, or two or more thereof may be used in any combination and ratio.

・ Distribution method:
As a method for dispersing the charge generation material in a solvent or a dispersion medium, a known dispersion method such as a ball mill dispersion method, an attritor dispersion method, or a sand mill dispersion method can be used. At this time, it is effective to refine the charge generating material particles to a particle size of usually 0.5 μm or less, preferably 0.3 μm or less, more preferably 0.15 μm or less.

・ Film thickness:
The film thickness of the charge generation layer is usually 0.1 μm or more, preferably 0.15 μm or more, usually 10 μm or less, preferably 0.6 μm or less.

(Charge transport layer of laminated photosensitive layer)
The charge transport layer of the multilayer photosensitive layer is prepared by dissolving or dispersing the binder resin in a solvent and dispersing the charge transport material to prepare a coating solution. In the case of a multilayer type photoreceptor, it is formed by coating on a conductive support (or on the undercoat layer when an undercoat layer is provided) and binding fine particles of a charge transport material with a binder resin.

・ Binder resin:
Examples of the binder resin include polymers and copolymers of vinyl compounds such as butadiene resin, styrene resin, vinyl acetate resin, vinyl chloride resin, acrylic ester resin, methacrylic ester resin, vinyl alcohol resin, ethyl vinyl ether, and polyvinyl butyral. Resin, polyvinyl formal resin, partially modified polyvinyl acetal, polycarbonate resin, polyester resin, polyarylate resin, polyamide resin, polyurethane resin, cellulose ester resin, phenoxy resin, silicone resin, silicone-alkyd resin, poly-N-vinylcarbazole resin, etc. Is mentioned. These binder resins may be modified with a silicon reagent or the like. Of the binder resins, polycarbonate resins and polyarylate resins are particularly preferable.

  Among polycarbonate resins and polyarylate resins, polycarbonate resins and polyarylate resins containing a bisphenol residue and / or a biphenol residue represented by the following structural formula are preferable from the viewpoint of sensitivity and residual potential. To polycarbonate resin is more preferable.

These binder resins can also be used after being crosslinked with heat, light or the like using an appropriate curing agent.
In addition, any one kind of binder resin may be used alone, or two or more kinds may be mixed and used in an arbitrary combination and ratio.

・ Charge transport materials:
The charge transport material is not particularly limited as long as it is a known material. For example, aromatic nitro compounds such as 2,4,7-trinitrofluorenone, cyano compounds such as tetracyanoquinodimethane, diphenoquinone, etc. Electron withdrawing substances such as quinone compounds, carbazole derivatives, indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, thiadiazole derivatives, heterocyclic compounds such as benzofuran derivatives, aniline derivatives, hydrazone derivatives, aromatic amine derivatives, stilbene derivatives, Examples thereof include butadiene derivatives, enamine derivatives and those obtained by bonding a plurality of these compounds, or electron donating substances such as polymers having groups composed of these compounds in the main chain or side chain. Among these, carbazole derivatives, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine derivatives, and those in which a plurality of these compounds are bonded are preferable.

・ Combination ratio:
The ratio of the binder resin to the charge transport material is usually 20 parts by weight or more with respect to 100 parts by weight of the binder resin, and preferably 30 parts by weight or more from the viewpoint of reducing the residual potential. From the viewpoint, 40 parts by weight or less is more preferable. On the other hand, from the viewpoint of thermal stability of the photosensitive layer, it is usually 150 parts by weight or less, preferably 120 parts by weight or less from the viewpoint of compatibility between the charge transport material and the binder resin, and 100 from the viewpoint of printing durability. The amount is preferably not more than parts by weight, and particularly preferably not more than 80 parts by weight from the viewpoint of scratch resistance.

-Solvent or dispersion medium and dispersion method:
The type of the solvent or dispersion medium and the method for dispersing the charge transport material in the solvent or dispersion medium are as described in the section <Charge generation layer of laminated photosensitive layer>.

・ Film thickness:
The thickness of the charge transport layer is not particularly limited, but is usually 5 μm or more, particularly 10 μm or more, and usually 50 μm or less, especially 45 μm or less, and further 30 μm or less from the viewpoints of long life, image stability, and high resolution. It is preferable to set it as the range.

(Single layer type photosensitive layer)
A single-layer type photosensitive layer is obtained by dissolving a coating solution obtained by dissolving or dispersing a charge generating substance, a charge transporting substance, and a binder resin on a conductive support (if an undercoat layer is provided, And the fine particles of the charge generation material and the charge transport material are bound by a binder resin. As the charge generation material, those described in the section <Charge generation layer of multilayer photosensitive layer> are used. As the charge transport material and the binder resin, those of <Charge transport layer of multilayer photosensitive layer> are used. Those described in the column are used. The ratios of the charge generation material and the charge transport material to the binder resin are also as described in the above sections <Charge generation layer of multilayer photosensitive layer> and <Charge transport layer of multilayer photosensitive layer>, respectively.

  If the phthalocyanine crystal dispersed in the single-layer type photosensitive layer is too small, sufficient sensitivity cannot be obtained, and if it is too large, there is an adverse effect on chargeability and sensitivity. The ratio of the charge generating material is preferably 0.1% by weight or more, more preferably 1% by weight or more, and preferably 50% by weight or less, more preferably 20% by weight or less.

The kind of the solvent or dispersion medium and the dispersion method are as described in the above section <Charge generation layer of laminated photosensitive layer>.
The film thickness of the single-layer type photosensitive layer is usually 5 μm or more, preferably 10 μm or more, and usually 100 μm or less, preferably 50 μm or less.

(Other ingredients)
The photosensitive layer has well-known antioxidants, plasticizers, ultraviolet absorbers, electron-withdrawing compounds to improve film-forming properties, flexibility, coating properties, stain resistance, gas resistance, light resistance, etc. In addition, additives such as a leveling agent and a visible light shielding agent may be contained.

<II-2-4. Other layers>
As the configuration of the electrophotographic photosensitive member, in addition to the above-described layers, other layers may be provided without departing from the spirit of the present invention.

For example, a protective layer may be provided on the photosensitive layer for the purpose of preventing the photosensitive layer from being worn out or preventing or reducing the deterioration of the photosensitive layer due to a discharge substance generated from a charger or the like. The protective layer is formed by containing a conductive material in an appropriate binder resin, or charge transport such as a triphenylamine skeleton as described in JP-A-9-190004, JP-A-10-252377, etc. A copolymer using a compound having a function can be used. Examples of the conductive material include aromatic amino compounds such as TPD (N, N′-diphenyl-N, N′-bis- (m-tolyl) benzidine), antimony oxide, indium oxide, tin oxide, titanium oxide, and tin oxide. -Metal oxides such as antimony oxide, aluminum oxide, and zinc oxide can be used, but are not limited thereto. As the binder resin used for the protective layer, known resins such as polyamide resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinyl ketone resin, polystyrene resin, polyacrylamide resin, and siloxane resin can be used. Also, a copolymer of the above resin with a skeleton having a charge transporting ability such as a triphenylamine skeleton as described in JP-A-9-190004 and JP-A-10-252377 can be used. The protective layer is preferably configured to have an electric resistance of 10 ⁹ to 10 ¹⁴ Ω · cm. If the electrical resistance is too high, the residual potential tends to increase and an image with a lot of fog tends to be formed. On the other hand, if the electrical resistance is too low, the image tends to be blurred and the resolution is lowered. In addition, the protective layer must be configured so as not to substantially impede transmission of light irradiated for image exposure.

  The surface layer (photosensitive layer) of the electrophotographic photosensitive member is also used for the purpose of reducing the frictional resistance and wear on the surface of the electrophotographic photosensitive member and increasing the transfer efficiency of toner from the electrophotographic photosensitive member to a transfer belt or paper. , A protective layer or the like) may contain a fluorine-based resin, a silicone resin, a polyethylene resin, or the like. Moreover, you may contain the particle | grains which consist of these resin, the particle | grains of an inorganic compound, etc.

<II-2-5. Formation method of each layer>
Each layer constituting these photoconductors is formed by applying the coating solution obtained by the above-described method on a support using a known coating method, repeating the coating and drying steps for each layer, and sequentially coating the layers. The

  When forming a photosensitive layer of a single-layer type photoreceptor and a charge transport layer of a function-separated type photoreceptor, the solid content concentration of the coating solution is usually 5% by weight or more, especially 10% by weight or more, and usually 40% by weight or less. Of these, the range of 35% by weight or less is preferable. Further, the viscosity of the coating solution is usually 10 mPa · s or more, preferably 50 mPa · s or more, and usually 500 mPa · s or less, preferably 400 mPa · s or less.

  When the charge generation layer of the function-separated type photoreceptor is formed, the solid content concentration of the coating solution is usually 0.1% by weight or more, especially 1% by weight or more, and usually 15% by weight or less, especially 10% or less. Is preferable. In addition, the viscosity of the coating liquid is preferably 0.01 mPa · s or more, particularly 0.1 mPa · s or more, and usually 20 mPa · s or less, particularly 10 mPa · s or less.

  Examples of the coating method include a dip coating method, a spray coating method, a spinner coating method, a bead coating method, a wire bar coating method, a blade coating method, a roller coating method, an air knife coating method, and a curtain coating method. Other known coating methods can also be used.

  The method for drying the coating solution is not particularly limited, but it is usually preferable to dry by heating at room temperature without touching or blowing with air. The heating temperature is in the range of 30 to 200 ° C. in particular for 1 minute to 2 hours, and the heating temperature may be constant or may be changed while drying.

[III. Image forming apparatus]
[III-1. Basic configuration of 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 arranged along the outer peripheral surface of the electrophotographic photoreceptor 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. Examples of the charging device include a corona charging device such as a corotron and a scorotron, a direct charging device (contact type charging device) that charges a direct charging member to which a voltage is applied by contacting the photosensitive member surface, and a contact type charging device such as a charging brush. 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. Moreover, as a voltage applied at the time of charging, it is possible to use only a direct current voltage or to superimpose an alternating current on a 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. 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 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 silicone 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 silicone resin or urethane resin, a metal blade such as stainless steel, aluminum, copper, brass, phosphor bronze, or a blade obtained by coating such 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.

As the toner, in addition to the pulverized toner, chemical toners such as suspension granulation, suspension polymerization, and emulsion polymerization aggregation 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 a sphere such as a potato or rugby ball can also be used. . The polymerized toner is excellent in charging uniformity and transferability, and is preferably used for high image quality.
In the present invention, the toner [III-2. It is preferable to use a specific toner (the toner according to the present invention) described in detail in the section of “Toner”.

  The type of the toner T is arbitrary, and chemical toners such as suspension granulation, suspension polymerization, and emulsion polymerization aggregation can be used in addition to powdered toner. In the case of chemical toners, those having a small particle size of about 4 to 8 μm are preferable, and toner particles having various shapes from those close to a sphere to a potato that is out of a sphere are used. Can be used. In particular, the polymerized toner is excellent in charging uniformity and transferability, and is suitably used for high image quality.

  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 disposed so as 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. Note that the cleaning device 6 can be omitted when the amount of residual toner is small or almost absent.

  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. Each of the upper and lower fixing members 71 and 72 includes a fixing roll in which a metal base tube such as stainless steel or aluminum is coated with silicon rubber, a fixing roll in which Teflon (registered trademark) resin is coated, and a fixing sheet. A member can be used. 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.

  The type of the fixing device is not particularly limited, and a fixing device of any type such as heat roller fixing, flash fixing, oven fixing, pressure fixing, etc. can be provided including those used here.

  In the image forming apparatus configured as described above, an image is recorded according to the following method (the image forming method of the present invention).

  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 with 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 photoreceptor 1 is used alone or in combination with one or more elements 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. And an integral type cartridge (hereinafter referred to as “electrophotographic photosensitive member cartridge” as appropriate), and the electrophotographic photosensitive member cartridge is detachable from a main body of an image forming apparatus such as a copying machine or a laser beam printer. Good. In this case, a cartridge case configured to be detachable from the image forming apparatus is used, and the electrophotographic photosensitive member 1 is accommodated and supported by the cartridge case alone or in combination with the above-described elements. It can be. With this configuration, for example, when the electrophotographic photosensitive member 1 and other members deteriorate, 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.

[III-2. toner〕
In the image forming apparatus of the present invention, it is preferable to use a toner having specific characteristics described below (hereinafter sometimes referred to as “the toner according to the present invention”) as the toner.

<Average circularity of toner>
The toner according to the present invention preferably has an average circularity measured by a flow type particle image analyzer of usually 0.940 or more, particularly 0.950 or more, more preferably 0.960 or more. As the shape of the toner is closer to a sphere, the charge amount is less likely to be localized in the toner particles, and the developability tends to be uniform. The upper limit of the average circularity is not limited as long as it is 1.000 or less. However, the closer the toner shape is to a spherical shape, the easier the cleaning failure occurs, and the production of a perfect spherical toner is difficult. Therefore, it is usually 0.995 or less, preferably 0.990 or less.

The average circularity is used as a simple method for quantitatively expressing the shape of toner particles. In the present invention, measurement is performed using a flow type particle image analyzer FPIA-2000 manufactured by Sysmex Corporation, and the circularity a of the measured particle is obtained by the following equation (A).
Circularity a = L ₀ / L (A)
(In Formula (A), L ₀ represents the perimeter of a circle having the same projected area as the particle image, and L represents the perimeter of the particle image when image processing is performed.)

  The circularity is an index of the degree of unevenness of the toner particles, and indicates 1.00 when the toner is a perfect sphere. The more complicated the surface shape, the smaller the circularity.

  A specific method for measuring the average circularity is as follows. That is, a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 20 mL of water from which impurities in the container have been removed in advance, and about 0.05 g of a measurement sample (toner) is further added. The suspension in which the sample is dispersed is irradiated with ultrasonic waves for 30 seconds, the dispersion concentration is set to 3.0 to 8.0 thousand pieces / μL, and the above flow type particle image measuring apparatus is used, and the flow type particle image measuring apparatus is used. The circularity distribution of the particles having the equivalent circle diameter is measured.

<Toner type and manufacturing method>
Various types of toner are usually used depending on the production method, but the type of toner according to the present invention is not limited, and any of them can be used.
Hereinafter, the toner manufacturing method and the type of toner will be described.

  The toner according to the present invention may be produced by any conventionally known method. Examples of the toner production method include a polymerization method and a melt suspension method, and so-called polymerization method toner that generates toner particles in an aqueous medium is preferable. Examples of the polymerization toner include suspension polymerization toner and emulsion polymerization aggregation toner. In particular, the emulsion polymerization aggregation method is a method for producing a toner by aggregating polymer resin fine particles and a coloring agent in a liquid medium, and adjusting the particle size and circularity of the toner by controlling the aggregation conditions. Is preferable.

  In order to improve the releasability, low-temperature fixing property, high-temperature offset property, filming resistance and the like of the toner, a method of incorporating a low softening point substance (so-called wax) into the toner has been proposed. In the melt-kneading pulverization method, it is difficult to increase the amount of wax contained in the toner, and the limit is about 5% by weight with respect to the polymer (binder resin). On the other hand, the polymerized toner can contain a low softening point substance in a large amount (5 to 30% by weight) as described in JP-A-5-88409 and JP-A-11-143125. The polymer here is one of the materials constituting the toner. For example, in the case of a toner manufactured by an emulsion polymerization aggregation method described later, the polymer is obtained by polymerizing a polymerizable monomer.

Hereinafter, the toner produced by the emulsion polymerization aggregation method will be described in more detail.
When a toner is produced by an emulsion polymerization aggregation method, the production process usually includes a polymerization process, a mixing process, an aggregation process, a fusion process, and a washing / drying process. That is, generally, polymer primary particles are obtained by emulsion polymerization (polymerization step), and if necessary, a colorant (pigment), wax, charge control agent, etc. are dispersed in a dispersion containing the polymer primary particles. The body is mixed (mixing step), and a flocculant is added to the dispersion to agglomerate the primary particles to form particle aggregates (aggregation step). Thus, particles are obtained (fusion process), and the obtained particles are washed and dried (washing / drying process) to obtain mother particles.

(1. Polymerization process)
The polymer fine particles (polymer primary particles) are not particularly limited. Therefore, either a fine particle obtained by polymerizing a polymerizable monomer in a liquid medium by a suspension polymerization method, an emulsion polymerization method or the like, or a fine particle obtained by pulverizing a lump of a polymer such as a resin is a polymer primary particle. It may be used as However, a polymerization method, particularly an emulsion polymerization method, in particular, a method using wax as a seed in emulsion polymerization is preferable. When wax is used as a seed in emulsion polymerization, fine particles having a structure in which the polymer wraps the wax can be produced as polymer primary particles. According to this method, the wax can be contained in the toner without being exposed on the surface of the toner. For this reason, there is no contamination of the apparatus member by the wax, the chargeability of the toner is not impaired, and the low temperature fixing property, high temperature offset property, filming resistance, releasability, etc. of the toner can be improved. it can.

  Hereinafter, a description will be given of a method of performing emulsion polymerization using wax as a seed, thereby obtaining polymer primary particles.

  The emulsion polymerization method may be performed according to a conventionally known method. Usually, wax is dispersed in a liquid medium in the presence of an emulsifier to form wax fine particles, and a polymerization initiator and a polymerizable monomer that gives a polymer by polymerization, that is, a compound having a polymerizable carbon-carbon double bond. In addition, a chain transfer agent, a pH adjuster, a polymerization degree adjuster, an antifoaming agent, a protective colloid, an internal additive, and the like are mixed and stirred as necessary for polymerization. As a result, an emulsion is obtained in which polymer fine particles (that is, polymer primary particles) having a structure in which the polymer wraps the wax are dispersed in the liquid medium. Examples of the structure in which the polymer wraps the wax include a core-shell type, a phase separation type, and an occlusion type, and the core-shell type is preferable.

(1-i. Wax)
As the wax, any known wax that can be used for this purpose can be used. For example, low molecular weight polyethylene, low molecular weight polypropylene, copolymer polyethylene and other olefin waxes; paraffin wax; alkyl group silicone wax; low molecular weight polytetrafluoroethylene and other fluororesin waxes; higher fatty acids such as stearic acid; eicosanol Long-chain aliphatic alcohols such as behenate behenate, montanate ester, stearic acid ester-based wax having a long-chain aliphatic group; distearyl ketone and other ketones having a long-chain alkyl group; hydrogenated castor oil, Plant waxes such as carnauba wax; esters or partial esters obtained from polyhydric alcohols such as glycerin and pentaerythritol and long chain fatty acids; higher fatty acid amides such as oleic acid amide and stearic acid amide; low molecular weight poly Ester and the like. Especially, what has at least 1 the endothermic peak by a differential thermal analysis (DSC) in 50-100 degreeC is preferable.

Among the waxes, for example, ester waxes, paraffin waxes, olefin waxes such as low molecular weight polypropylene and copolymer polyethylene, silicone waxes, and the like are preferable because a release effect can be obtained in a small amount. Paraffin wax is particularly preferable.
In addition, 1 type may be used for wax and it may use 2 or more types together by arbitrary combinations and a ratio.

  When using wax, the amount used is arbitrary. However, it is desirable that the wax is usually 3 parts by weight or more, preferably 5 parts by weight or more, and usually 40 parts by weight or less, preferably 30 parts by weight or less based on 100 parts by weight of the polymer. If the amount of wax is too small, the fixing temperature range may be insufficient. If the amount is too large, the apparatus member may be contaminated and image quality may be deteriorated.

(1-ii. Emulsifier)
There is no restriction | limiting in an emulsifier, Arbitrary things can be used in the range which does not impair the effect of this invention remarkably. For example, any of nonionic, anionic, cationic and amphoteric surfactants can be used.

  Examples of the nonionic surfactant include polyoxyalkylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyalkylene alkyl phenyl ethers such as polyoxyethylene octylphenyl ether, and sorbitan fatty acid esters such as sorbitan monolaurate. And the like.

  Examples of the anionic surfactant include fatty acid salts such as sodium stearate and sodium oleate, alkylaryl sulfonates such as sodium dodecylbenzene sulfonate, and alkyl sulfate salts such as sodium lauryl sulfate. .

Furthermore, examples of the cationic surfactant include alkylamine salts such as laurylamine acetate, and quaternary ammonium salts such as lauryltrimethylammonium chloride.
Examples of amphoteric surfactants include alkylbetaines such as lauryl betaine.

Among these, nonionic surfactants and anionic surfactants are preferable.
In addition, 1 type may be used for an emulsifier and it may use 2 or more types together by arbitrary combinations and a ratio.

  The amount of the emulsifier is arbitrary as long as the effects of the present invention are not significantly impaired. Usually, the emulsifier is used in a proportion of 1 part by weight or more and 10 parts by weight or less based on 100 parts by weight of the polymerizable monomer.

(1-iii. Liquid medium)
As the liquid medium, an aqueous medium is usually used. Of these, water is preferred. However, the quality of the liquid medium is also related to the coarsening due to reaggregation of particles in the liquid medium. When the conductivity of the liquid medium is high, the dispersion stability with time tends to deteriorate. Therefore, when an aqueous medium such as water is used as the liquid medium, ion-exchanged water or distilled water that has been desalted so that its conductivity is usually 10 μS / cm or less, preferably 5 μS / cm or less is used. It is preferable. The conductivity is measured at 25 ° C. using a conductivity meter (personal SC meter model SC72 and detector SC72SN-11 manufactured by Yokogawa Electric Corporation).

Although there is no restriction | limiting in the usage-amount of a liquid medium, Usually, the quantity about 1 weight times or more and 20 weight times or less is used with respect to a polymerizable monomer.
In addition, a liquid medium may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  By dispersing the wax in the liquid medium in the presence of an emulsifier, fine wax particles are obtained. The order of blending the emulsifier and the wax in the liquid medium is arbitrary, but usually the emulsifier is first blended in the liquid medium and then the wax is mixed. Moreover, an emulsifier may be mix | blended at once with a liquid medium, and may be mix | blended continuously.

(1-iv. Polymerization initiator)
After preparing the wax fine particles, a polymerization initiator is blended in the liquid medium. Any polymerization initiator can be used as long as the effects of the present invention are not significantly impaired. For example, persulfates such as sodium persulfate and ammonium persulfate; organic peroxides such as t-butyl hydroperoxide, cumene hydroperoxide and p-menthane hydroperoxide; inorganics such as hydrogen peroxide Examples include peroxides. Of these, inorganic peroxides are preferable. In addition, 1 type may be used for a polymerization initiator and it may use 2 or more types together by arbitrary combinations and a ratio.

  Other examples of polymerization initiators include persulfates, organic or inorganic peroxides and reducing organic compounds such as ascorbic acid, tartaric acid, citric acid, sodium thiosulfate, sodium bisulfite, sodium metabisulfite, etc. It is also possible to use redox initiators in combination with other reducing inorganic compounds. In this case, reducing inorganic compounds may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  There is no restriction | limiting in the usage-amount of a polymerization initiator, Although it is arbitrary, Usually, it is used in the ratio of 0.05 weight part or more and 2 weight part or less with respect to 100 weight part of polymerizable monomers.

(1-v. Polymerizable monomer)
After preparing the wax fine particles, a polymerizable monomer is blended in the liquid medium in addition to the polymerization initiator. The polymerizable monomer is not particularly limited, and examples thereof include styrenes, (meth) acrylic acid esters, acrylamides, monomers having Bronsted acidic groups (hereinafter sometimes simply referred to as “acidic monomers”), Bronsted, and the like. A monofunctional monomer such as a monomer having a basic group (hereinafter sometimes simply referred to as “basic monomer”) is mainly used. Further, a monofunctional monomer can be used in combination with a polyfunctional monomer.

  Examples of styrenes include styrene, methyl styrene, chlorostyrene, dichlorostyrene, p-tert-butyl styrene, pn-butyl styrene, pn-nonyl styrene, and the like.

  Examples of (meth) acrylic acid esters include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, hydroxyethyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and methacrylic acid. Examples include ethyl acetate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, hydroxyethyl methacrylate, and 2-ethylhexyl methacrylate.

  Examples of acrylamides include acrylamide, N-propyl acrylamide, N, N-dimethyl acrylamide, N, N-dipropyl acrylamide, N, N-dibutyl acrylamide, and the like.

  Examples of acidic monomers include monomers having a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, and cinnamic acid; monomers having a sulfonic acid group such as sulfonated styrene; and sulfonamides such as vinylbenzenesulfonamide. And monomers having a group.

  Examples of basic monomers include aromatic vinyl compounds having an amino group such as aminostyrene, nitrogen-containing heterocyclic-containing monomers such as vinylpyridine and vinylpyrrolidone; amino groups such as dimethylaminoethyl acrylate and diethylaminoethyl methacrylate ( And (meth) acrylic acid esters.

  In addition, the acidic monomer and the basic monomer may exist as a salt with a counter ion.

  Examples of the multifunctional monomer include divinylbenzene, hexanediol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol diacrylate, diallyl phthalate. Etc. It is also possible to use a monomer having a reactive group such as glycidyl methacrylate, N-methylolacrylamide, or acrolein. Among these, radically polymerizable bifunctional monomers, particularly divinylbenzene and hexanediol diacrylate are preferable.

Among these, the polymerizable monomer is preferably composed of at least styrenes, (meth) acrylic acid esters, and acidic monomers having a carboxyl group.
In particular, styrene is preferred as the styrene, butyl acrylate is preferred as the (meth) acrylic acid ester, and acrylic acid is preferred as the acidic monomer having a carboxyl group.

  In addition, 1 type may be used for a polymerizable monomer and it may use 2 or more types together by arbitrary combinations and a ratio.

  When emulsion polymerization is performed using wax as a seed, it is preferable to use an acidic monomer or a basic monomer and a monomer other than these in combination. This is because the dispersion stability of the polymer primary particles can be improved by using an acidic monomer or a basic monomer in combination.

  At this time, the compounding amount of the acidic monomer or basic monomer is arbitrary, but the amount of the acidic monomer or basic monomer used relative to 100 parts by weight of the total polymerizable monomer is usually 0.05 parts by weight or more, preferably 0.5 parts by weight. It is desirable that the amount is not less than 1 part by weight, more preferably not less than 1 part by weight, and usually not more than 10 parts by weight, preferably not more than 5 parts by weight. If the blending amount of the acidic monomer or basic monomer is too small, the dispersion stability of the polymer primary particles may be deteriorated, and if it is too large, the chargeability of the toner may be adversely affected.

  In addition, it is preferable to use a polyfunctional monomer because the fixability of the toner can be improved. When a polyfunctional monomer is used in combination, the blending amount is arbitrary, but the blending amount of the polyfunctional monomer with respect to 100 parts by weight of the polymerizable monomer is usually 0.005 part by weight or more, preferably 0.1 part by weight or more. More preferably, it is 0.3 parts by weight or more, and usually 5 parts by weight or less, preferably 3 parts by weight or less, more preferably 1 part by weight or less. If the amount of the polyfunctional monomer is too small, the high temperature offset resistance may be inferior, and if it is too much, the low temperature fixing property may be inferior.

  The method for blending the polymerizable monomer into the liquid medium is not particularly limited. For example, any of batch addition, continuous addition, and intermittent addition may be used, but it is preferable to blend continuously from the viewpoint of reaction control. Moreover, when using multiple types of polymerizable monomer together, each polymerizable monomer may be mix | blended separately, and may be mix | blended after mixing beforehand. Furthermore, you may mix | blend, changing the composition of the mixture of multiple types of monomer.

(1-vi. Chain transfer agent, etc.)
After preparing the above wax fine particles, in addition to the above-mentioned polymerization initiator and polymerizable monomer, the liquid medium includes a chain transfer agent, a pH adjuster, a polymerization degree adjuster, an antifoaming agent, a protection as necessary. Add additives such as colloids and internal additives. Any of these additives can be used as long as the effects of the present invention are not significantly impaired. Moreover, these additives may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  Any known chain transfer agent can be used. Specific examples include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropylxanthogen, carbon tetrachloride, trichlorobromomethane and the like. Moreover, a chain transfer agent is normally used in the ratio of 5 weight part or less with respect to 100 weight part of polymerizable monomers.

  Further, as the protective colloid, any known colloid that can be used for this purpose can be used. Specific examples include partially or completely saponified polyvinyl alcohols such as polyvinyl alcohol, cellulose derivatives such as hydroxyethyl cellulose, and the like.

  Examples of the internal additive include those for modifying the adhesiveness, cohesiveness, fluidity, chargeability, surface resistance and the like of toners such as silicone oil, silicone varnish, and fluorine oil.

(1-vii. Polymer primary particles)
Polymer initiators, polymerizable monomers, and additives as necessary are mixed in a liquid medium containing wax fine particles, stirred, and polymerized to obtain polymer primary particles. The polymer primary particles can be obtained in the form of an emulsion in a liquid medium.

  There is no restriction | limiting in the order which mixes a polymerization initiator, a polymerizable monomer, an additive, etc. with a liquid medium. Further, there are no restrictions on the method of mixing and stirring, and the method is arbitrary.

  Furthermore, the temperature at the time of the polymerization reaction (emulsion polymerization reaction) is arbitrary as long as the reaction proceeds, but is usually 50 ° C. or higher, preferably 60 ° C. or higher, more preferably 70 ° C. or higher, and usually 120 ° C. or lower, preferably Is preferably 100 ° C. or lower, more preferably 90 ° C. or lower.

  The volume average particle diameter of the polymer primary particles is not particularly limited, but is usually 0.02 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, and usually 3 μm or less, preferably 2 μm or less, more preferably Is preferably 1 μm or less. If the volume average particle size is too small, it may be difficult to control the aggregation rate. If the volume average particle size is too large, the particle size of the toner obtained by aggregation tends to be large, and the target particles It may be difficult to obtain a toner having a diameter. The volume average particle diameter can be measured with a particle size analyzer using a dynamic light scattering method described later.

  In the present invention, the volume particle size distribution is measured by a dynamic light scattering method. This method obtains the particle size distribution by detecting the speed of Brownian motion of finely dispersed particles, irradiating the particles with laser light, and detecting light scattering (Doppler shift) with different phases according to the speed. It is. In actual measurement, the above volume particle size was measured using the following settings using an ultrafine particle size distribution measuring apparatus (Nikkiso Co., Ltd., UPA-EX150, hereinafter abbreviated as UPA) using a dynamic light scattering method. Do.

Measurement upper limit: 6.54 μm
Measurement lower limit: 0.0008 μm
Number of channels: 52
Measurement time: 100 sec.
Particle permeability: Absorption Particle refractive index: N / A (not applicable)
Particle shape: non-spherical density: 1 g / cm ³
Dispersion medium type: WATER
Dispersion medium refractive index: 1.333

  At the time of measurement, measurement is performed with a sample in which a dispersion of particles is diluted with a liquid medium so that the sample concentration index is in the range of 0.01 to 0.1 and is dispersed with an ultrasonic cleaner. And the volume average particle diameter in connection with this invention is measured by using the result of said volume particle size distribution as an arithmetic mean value.

  The polymer constituting the polymer primary particles may be referred to as a peak molecular weight (hereinafter referred to as “GPC peak molecular weight”) in a molecular weight distribution measured by gel permeation chromatography (hereinafter sometimes abbreviated as “GPC” as appropriate). At least one is usually 3,000 or more, preferably 10,000 or more, more preferably 30,000 or more, and usually 100,000 or less, preferably 70,000 or less, more preferably 60,000 or less. desirable. When the peak molecular weight is in the above range, the durability, storage stability, and fixability of the toner tend to be good. Here, as the peak molecular weight, a value converted to polystyrene is used, and components insoluble in a solvent are excluded in measurement. The peak molecular weight can be measured in the same manner as the toner described later.

  In particular, when the polymer is a styrenic resin, the number average molecular weight of the polymer measured by GPC is usually 2000 or more, preferably 2500 or more, more preferably 3000 or more, and usually 50,000 or less, preferably It is desirable that it is 40,000 or less, more preferably 35,000 or less. The weight average molecular weight of the polymer measured by GPC is usually 20,000 or more, preferably 30,000 or more, more preferably 50,000 or more, and usually 1,000,000 or less, preferably 500,000 or less. When a styrene resin in which at least one of the number average molecular weight and the weight average molecular weight, preferably both fall within the above ranges, is used as the polymer, the obtained toner has good durability, storage stability and fixability. is there. Further, the molecular weight distribution may have two main peaks. The styrene resin refers to a resin in which styrenes occupy usually 50% by weight or more, preferably 65% by weight or more based on the total polymer.

  In addition, the softening point of the polymer (hereinafter sometimes abbreviated as “Sp”) is usually 150 ° C. or lower, preferably 140 ° C. or lower, from the viewpoint of low energy fixing, and is resistant to high temperature offset. In view of durability, it is usually 80 ° C. or higher, preferably 100 ° C. or higher. Here, the softening point of the polymer was measured in a flow tester under the conditions of 1.0 g of a sample of a nozzle 1 mm × 10 mm, a load of 30 kg, a preheating time of 50 ° C. for 5 minutes, and a heating rate of 3 ° C./min. The temperature at the midpoint of the strand from the start to the end of the flow can be obtained.

  Furthermore, the glass transition temperature [Tg] of the polymer is usually 80 ° C. or lower, preferably 70 ° C. or lower. If the glass transition temperature [Tg] of the polymer is too high, there is a possibility that low-energy fixing cannot be performed. The lower limit of the glass transition temperature [Tg] of the polymer is usually 40 ° C. or higher, preferably 50 ° C. or higher. If the glass transition temperature [Tg] of the polymer is too low, the blocking resistance may be lowered. Here, the glass transition temperature [Tg] of the polymer is the intersection of the two tangent lines by drawing a tangent line at the start of the transition (inflection) of the curve measured at a heating rate of 10 ° C./min in a differential scanning calorimeter. It can be calculated as the temperature.

  The softening point and glass transition temperature [Tg] of the polymer can be adjusted to the above ranges by adjusting the kind of the polymer, the monomer composition ratio, the molecular weight, and the like.

(2. Mixing step and aggregation step)
By mixing and agglomerating pigment particles in the emulsion in which the polymer primary particles are dispersed, an emulsion of aggregates (aggregated particles) containing the polymer and the pigment is obtained. At this time, as the pigment, it is preferable to prepare a pigment particle dispersion that is previously uniformly dispersed in a liquid medium using a surfactant or the like, and mix it with an emulsion of polymer primary particles. At this time, an aqueous solvent such as water is usually used as the liquid medium of the pigment particle dispersion, and the pigment particle dispersion is prepared as an aqueous dispersion. At that time, if necessary, a wax, a charge control agent, a release agent, an internal additive and the like may be mixed into the emulsion. Moreover, in order to maintain the stability of the pigment particle dispersion, the above-described emulsifier may be added.

  As the polymer primary particles, the polymer primary particles obtained by emulsion polymerization can be used. Under the present circumstances, 1 type may be used for a polymer primary particle, and 2 or more types may be used together by arbitrary combinations and a ratio. Furthermore, polymer primary particles (hereinafter referred to as “combined polymer particles” as appropriate) produced with raw materials and reaction conditions different from those of the emulsion polymerization described above may be used in combination.

  Examples of the combined polymer particles include fine particles obtained by suspension polymerization or pulverization. Resin can be used as the material of such combined polymer particles, but as this resin, in addition to the monomer (co) polymer used for emulsion polymerization, for example, vinyl acetate, vinyl chloride, vinyl alcohol, Homopolymers or copolymers of vinyl monomers such as vinyl butyral and vinyl pyrrolidone, saturated polyester resins, polycarbonate resins, polyamide resins, polyolefin resins, polyarylate resins, polysulfone resins, thermoplastic resins such as polyphenylene ether resins, and Examples thereof include thermosetting resins such as unsaturated polyester resins, phenol resins, epoxy resins, urethane resins, and rosin-modified maleic resins. These combined polymer particles may be used alone or in combination of two or more in any combination and ratio. However, the ratio of the combined polymer particles is usually 5% by weight or less, preferably 4% by weight or less, more preferably 3% by weight or less based on the total of the polymer primary particles and the polymer of the combined polymer particles. .

Moreover, there is no restriction | limiting in a pigment, According to the use, arbitrary things can be used. However, the pigment usually exists in the form of particles as colorant particles, but it is preferable that the pigment particles have a smaller density difference from the polymer primary particles in the emulsion polymerization aggregation method. This is because when the density difference is smaller, a uniform aggregated state is obtained when the polymer temporary particles and the pigment are aggregated, and thus the performance of the obtained toner is improved. The density of the polymer primary particles is usually 1.1 to 1.3 g / cm ³ .

From the above viewpoint, the true density of the pigment particles measured by the pycnometer method defined in JIS K 5101-11-1: 2004 is usually 1.2 g / cm ³ or more, preferably 1.3 g / cm ³ or more. Also, it is usually less than 2.0 g / cm ³ , preferably 1.9 g / cm ³ or less, more preferably 1.8 g / cm ³ or less. When the true density of the pigment is large, the sedimentation property in a liquid medium tends to deteriorate. In addition, considering issues such as storage stability and sublimation, the pigment is preferably carbon black or an organic pigment.

  Examples of pigments that satisfy the above conditions include yellow pigments, magenta pigments, and cyan pigments shown below. Further, as the black pigment, carbon black or a mixture of the following yellow pigment / magenta pigment / cyan pigment mixed with black is used.

  Among these, carbon black used as a black pigment exists as an aggregate of very fine primary particles, and when dispersed as a pigment particle dispersion, the carbon black particles are likely to become coarse due to reaggregation. . The degree of reagglomeration of carbon black particles is correlated with the amount of impurities contained in carbon black (the degree of residual undecomposed organic matter), and if there are many impurities, coarsening due to reaggregation after dispersion is significant. Show the trend.

  For quantitative evaluation of the amount of impurities, the ultraviolet absorbance of the toluene extract of carbon black measured by the following measurement method is usually 0.05 or less, preferably 0.03 or less. In general, since carbon black of the channel method tends to have a large amount of impurities, the carbon black used for the toner according to the present invention is preferably manufactured by the furnace method.

The ultraviolet absorbance (λ _c ) of carbon black is determined by the following method. That is, first, 3 g of carbon black was sufficiently dispersed and mixed in 30 mL of toluene. Filter using 5C filter paper. After that, the filtrate was put into a quartz cell having an absorption part of 1 cm square, and the absorbance at a wavelength of 336 nm was measured using a commercially available ultraviolet spectrophotometer (λ _s ), and the absorbance of toluene alone was measured as a reference by the same method. From the value (λ _o ), the ultraviolet absorbance is determined by λ _c = λ _s −λ _o . Examples of commercially available spectrophotometers include an ultraviolet-visible spectrophotometer (UV-3100PC) manufactured by Shimadzu Corporation.

  As yellow pigments, for example, compounds typified by condensed azo compounds and isoindolinone compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 168, 180, 185 and the like are preferably used.

  Further, examples of magenta pigments include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 207, 209, 220, 221, 238, 254, C.I. I. Pigment Violet 19 or the like is preferably used.

  Among them, C.I. I. Pigment red 122, 202, 207, 209, C.I. I. A quinacridone pigment represented by pigment violet 19 is particularly preferred. This quinacridone pigment is suitable as a magenta pigment because of its clear hue and high light resistance. Among the quinacridone pigments, C.I. I. A compound represented by CI Pigment Red 122 is particularly preferable.

  Examples of cyan pigments that can be used include copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 and the like can be used particularly preferably.

  In addition, 1 type may be used for a pigment and it may use 2 or more types together by arbitrary combinations and a ratio.

  The above-mentioned pigment is dispersed in a liquid medium and mixed with an emulsion containing polymer primary particles after forming a pigment particle dispersion. At this time, the amount of the pigment particles used in the pigment particle dispersion is usually 3 parts by weight or more, preferably 5 parts by weight or more, and usually 50 parts by weight or less, preferably 40 parts by weight with respect to 100 parts by weight of the liquid medium. Or less. If the blending amount of the colorant exceeds the above range, the pigment concentration is high, so the probability that the pigment particles reaggregate in the dispersion may be increased. It may be difficult to obtain.

  The ratio of the amount of the pigment used relative to the polymer contained in the polymer primary particles is usually 1% by weight or more, preferably 3% by weight or more, and usually 20% by weight or less, preferably 15% by weight or less. If the amount of the pigment used is too small, the image density may become thin, and if it is too large, the aggregation control may be difficult.

Further, the pigment particle dispersion may contain a surfactant. Although there is no restriction | limiting in particular in this surfactant, For example, the thing similar to the surfactant illustrated as an emulsifier in description of an emulsion polymerization method is mentioned. Of these, nonionic surfactants, anionic surfactants such as alkylaryl sulfonates such as sodium dodecylbenzenesulfonate, and polymer surfactants are preferably used. Moreover, 1 type of surfactant may be used in this case, and 2 or more types may be used together by arbitrary combinations and a ratio.
In addition, the ratio of the pigment which occupies for a pigment particle dispersion is 10 to 50 weight% normally.

  Further, as the liquid medium of the pigment particle dispersion, an aqueous medium is usually used, and preferably water is used. At this time, the water quality of the polymer primary particles and the pigment particle dispersion is also related to the coarsening due to reaggregation of each particle, and when the conductivity is high, the dispersion stability with time tends to deteriorate. Therefore, it is preferable to use ion-exchanged water or distilled water that has been desalted so that the electrical conductivity is usually 10 μS / cm or less, preferably 5 μS / cm or less. The conductivity is measured at 25 ° C. using a conductivity meter (personal SC meter model SC72 and detector SC72SN-11 manufactured by Yokogawa Electric Corporation).

  Further, when the pigment is mixed with the emulsion containing the polymer primary particles, a wax may be mixed with the emulsion. As the wax, the same waxes described in the explanation of the emulsion polymerization method can be used. The wax may be mixed before, during or after mixing the pigment with the emulsion containing the polymer primary particles.

  Moreover, when mixing a pigment with the emulsion containing a polymer primary particle, you may mix a charge control agent with an emulsion.

  As the charge control agent, any known charge control agent can be used. Examples of the positively chargeable charge control agent include nigrosine dyes, quaternary ammonium salts, triphenylmethane compounds, imidazole compounds, polyamine resins, and the like. Examples of negative charge control agents include azo complex compound dyes containing atoms such as Cr, Co, Al, Fe, and B; metal salts or metal complexes of salicylic acid or alkylsalicylic acid; curixarene compounds, benzyl Examples include metal salts or metal complexes of acids, amide compounds, phenol compounds, naphthol compounds, and phenol amide compounds. Among them, it is preferable to select a colorless or light-colored toner in order to avoid a color tone trouble as a toner. Particularly, a positively chargeable charge control agent is preferably a quaternary ammonium salt or an imidazole compound, and a negatively chargeable charge control agent. As these, alkyl salicylic acid complex compounds and curixarene compounds containing atoms such as Cr, Co, Al, Fe and B are preferred. One type of charge control agent may be used, or two or more types may be used in any combination and ratio.

  Although there is no restriction | limiting in the usage-amount of a charge control agent, Usually 0.01 weight part or more with respect to 100 weight part of polymers, Preferably it is 0.1 weight part or more, Moreover, normally 10 weight part or less, Preferably it is 5 weight part. The following is desirable. If the amount of the charge control agent used is too small or too large, the desired charge amount may not be obtained.

The charge control agent may be mixed before, during or after mixing the pigment with the emulsion containing the polymer primary particles.
Moreover, it is desirable that the charge control agent is mixed at the time of aggregation in the state of being emulsified in a liquid medium (usually an aqueous medium) in the same manner as the pigment particles.

After the pigment is mixed in the emulsion containing the polymer primary particles, the polymer primary particles and the pigment are aggregated. As described above, the pigment is usually mixed as a pigment particle dispersion in mixing.
The aggregation method is not limited and is arbitrary, and examples thereof include heating, electrolyte mixing, pH adjustment, and the like. Among these, a method of mixing an electrolyte is preferable.

Examples of the electrolyte when the agglomeration is performed by mixing the electrolyte include chlorides such as NaCl, KCl, LiCl, MgCl ₂ , CaCl ₂ ; Na ₂ SO ₄ , K ₂ SO ₄ , Li ₂ SO ₄ , MgSO ₄ , Examples include inorganic salts such as sulfates such as CaSO ₄ , ZnSO ₄ , Al ₂ (SO ₄ ) ₃ , and Fe ₂ (SO ₄ ) ₃ ; organic salts such as CH ₃ COONa and C ₆ H ₅ SO ₃ Na. Of these, inorganic salts having a divalent or higher polyvalent metal cation are preferred.
In addition, 1 type may be used for electrolyte and 2 or more types may be used together by arbitrary combinations and a ratio.

  The amount of electrolyte used varies depending on the type of electrolyte, but is usually 0.05 parts by weight or more, preferably 0.1 parts by weight or more, and usually 25 parts by weight or less, based on 100 parts by weight of the solid component in the emulsion. Preferably it is 15 weight part or less, More preferably, it is 10 weight part or less. When agglomeration is performed by mixing electrolytes, if the amount of electrolyte used is too small, the agglomeration reaction proceeds slowly, and fine particles of 1 μm or less remain after the agglomeration reaction, or the average particle size of the obtained agglomerates is the target. If the amount of electrolyte used is too large, the agglomeration reaction will occur rapidly, making it difficult to control the particle size, resulting in coarse particles and irregular shapes in the resulting aggregate. May be included.

  The obtained agglomerates are preferably subsequently spheroidized by heating in a liquid medium, similarly to the secondary agglomerates (agglomerates that have undergone the melting step) described later. Heating may be performed under the same conditions as in the case of the secondary aggregate (same conditions as described in the description of the fusion process).

  On the other hand, when the aggregation is performed by heating, the temperature condition is arbitrary as long as the aggregation proceeds. Specific temperature conditions are usually 15 ° C. or higher, preferably 20 ° C. or higher, and aggregation is performed under a temperature condition of a polymer primary particle polymer glass transition temperature [Tg] or lower, preferably 55 ° C. or lower. . Although the time for agglomeration is arbitrary, it is usually 10 minutes or longer, preferably 60 minutes or longer, and usually 300 minutes or shorter, preferably 180 minutes or shorter.

  Moreover, it is preferable to add stirring when agglomerating. Although the apparatus used for stirring is not specifically limited, What has a double helical blade is preferable.

  The obtained agglomerates may proceed directly to the next step of forming a resin coating layer (encapsulation step), or may proceed to the encapsulation step after subsequent fusion treatment by heating in a liquid medium. . In addition, the encapsulation process is performed after the aggregation process, and the fusion process is performed by heating at a temperature equal to or higher than the glass transition temperature [Tg] of the encapsulated resin fine particles, which can simplify the process and deteriorate the toner performance (thermal degradation). Etc.) is not preferable.

(3. Encapsulation process)
After obtaining the aggregate, it is preferable to form a resin coating layer on the aggregate as necessary. The encapsulation process for forming a resin coating layer on the aggregate is a process for coating the aggregate with a resin by forming a resin coating layer on the surface of the aggregate. Thereby, the manufactured toner is provided with the resin coating layer. In the encapsulation process, the entire toner may not be completely covered, but the pigment makes it possible to obtain a toner that is not substantially exposed on the surface of the toner particles. Although there is no restriction | limiting in the thickness of the resin coating layer in this case, Usually, it is the range of 0.01-0.5 micrometer.

The method for forming the resin coating layer is not particularly limited, and examples thereof include a spray drying method, a mechanical particle composite method, an in-situ polymerization method, and a submerged particle coating method.
As a method for forming the resin coating layer by the spray drying method, for example, an aggregate forming an inner layer and resin fine particles forming a resin coating layer are dispersed in an aqueous medium to prepare a dispersion, A resin coating layer can be formed on the surface of the aggregate by spraying and drying.

  In addition, as a method for forming a resin coating layer by the mechanical particle composite method, for example, an aggregate that forms an inner layer and resin fine particles that form a resin coating layer are dispersed in a gas phase and mechanically formed in a narrow gap. In this method, resin fine particles are formed into a film on the surface of the aggregate by applying a strong force. For example, an apparatus such as a hybridization system (manufactured by Nara Machinery Co., Ltd.) or a mechanofusion system (manufactured by Hosokawa Micron Corporation) can be used.

Further, as the in-situ polymerization method, for example, an aggregate is dispersed in water, a monomer and a polymerization initiator are mixed, adsorbed on the surface of the aggregate, and heated to polymerize the monomer, and the inner layer In this method, a resin coating layer is formed on a certain aggregate surface.
The submerged particle coating method may be, for example, a method in which an aggregate forming an inner layer and resin fine particles forming an outer layer are reacted or bonded in an aqueous medium to form a resin coating layer on the surface of the aggregate forming the inner layer. Is a method of forming

  The resin fine particles used for forming the outer layer are particles mainly having a resin component smaller than the aggregate. The resin fine particles are not particularly limited as long as they are particles composed of a polymer. However, from the viewpoint that the thickness of the outer layer can be controlled, it is preferable to use resin fine particles similar to the polymer primary particles, the aggregates, or the fused particles obtained by fusing the aggregates. Resin fine particles similar to these polymer primary particles can be produced in the same manner as the polymer primary particles in the aggregate used for the inner layer.

The amount of resin fine particles used is arbitrary, but it is usually 1% by weight or more, preferably 5% by weight or more, and usually 50% by weight or less, preferably 25% by weight or less based on the toner particles. Is desirable.
Further, in order to effectively fix or fuse the resin fine particles to the aggregate, the particle size of the resin fine particles is preferably about 0.04 μm or more and 1 μm or less.

  The glass transition temperature [Tg] of the polymer component (resin component) used in the resin coating layer is usually 60 ° C. or higher, preferably 70 ° C. or higher, and usually 110 ° C. or lower. Further, the glass transition temperature [Tg] of the polymer component used for the resin coating layer is preferably higher by 5 ° C. or higher than the glass transition temperature [Tg] of the polymer primary particles, and is higher by 10 ° C. or higher. It is more preferable. If the glass transition temperature [Tg] is too low, storage in a general environment may be difficult, and if it is too high, sufficient meltability may not be obtained.

  Furthermore, it is preferable to contain polysiloxane wax in the resin coating layer. Thereby, the advantage of improvement in high temperature offset resistance can be obtained. Examples of the polysiloxane wax include silicone wax having an alkyl group.

  The content of the polysiloxane wax is not limited, but is usually 0.01% by weight or more, preferably 0.05% by weight or more, more preferably 0.08% by weight or more, and usually 2% by weight or less in the toner. Preferably it is 1 weight% or less, More preferably, you may be 0.5 weight% or less. If the amount of the polysiloxane wax in the resin coating layer is too small, the high temperature offset resistance may be insufficient, and if it is too large, the blocking resistance may be lowered.

  The method for containing the polysiloxane wax in the resin coating layer is arbitrary. For example, emulsion polymerization is performed using the polysiloxane wax as a seed, and the obtained resin fine particles and the aggregates forming the inner layer are mixed in an aqueous medium. And a resin coating layer containing a polysiloxane wax on the surface of the aggregate forming the inner layer.

(4. Fusion process)
In the fusing step, the aggregates are melt-integrated by heat-treating the aggregates.
In addition, when encapsulating resin fine particles are formed by forming a resin coating layer on the aggregate, the polymer constituting the aggregate and the resin coating layer on the surface thereof are integrated by heat treatment. It will be. Thereby, the pigment particles are obtained in a form that is not substantially exposed on the surface.

The temperature of the heat treatment in the fusion step is set to a temperature equal to or higher than the glass transition temperature [Tg] of the polymer primary particles constituting the aggregate. Moreover, when a resin coating layer is formed, it is set as the temperature more than the glass transition temperature [Tg] of the polymer component which forms a resin coating layer. Although specific temperature conditions are arbitrary, it is preferable that it is 5 degreeC or more normally higher than the glass transition temperature [Tg] of the polymer component which forms a resin coating layer. Although there is no restriction | limiting in the upper limit, below 50 degreeC higher than the glass transition temperature [Tg] of the polymer component which forms a resin coating layer is preferable.
The heat treatment time is usually 0.5 to 6 hours, although it depends on the treatment capacity and the production amount.

(5. Cleaning and drying process)
When the above-described steps are performed in a liquid medium, after the fusing step, the encapsulated resin particles obtained are washed and dried to remove the liquid medium, thereby obtaining a toner. There are no restrictions on the washing and drying methods, and they are arbitrary.

<Physical properties relating to toner particle size>
The volume average particle diameter [Dv] of the toner according to the present invention is not limited and may be any as long as the effects of the present invention are not significantly impaired, but usually 4 μm or more, preferably 5 μm or more, and usually 10 μm or less, preferably 8 μm. It is as follows. If the volume average particle diameter [Dv] of the toner is too small, the stability of the image quality may be lowered, and if it is too large, the resolution may be lowered.

The toner according to the present invention, the volume average particle diameter [D _v] divided by the number average particle diameter [D _n] to [D _v / D _n] is usually 1.0 or larger, and usually 1. It is desirable that it is 25 or less, preferably 1.20 or less, more preferably 1.15 or less. The value of [D _v / D _n ] represents the state of particle size distribution, and the closer this value is to 1.0, the sharper the particle size distribution. A sharper particle size distribution is desirable because the chargeability of the toner becomes uniform.

  Furthermore, the toner according to the present invention has a volume fraction having a particle diameter of 25 μm or more, usually 1% or less, preferably 0.5% or less, more preferably 0.1% or less, and still more preferably 0.05% or less. is there. The smaller this value, the better. This means that the ratio of the coarse powder contained in the toner is small. If the coarse powder is small, the amount of toner consumed during continuous development is small and the image quality is stable. Although it is most preferable that there is no coarse powder having a particle size of 25 μm or more, it is difficult in actual production, and usually it may not be 0.005% or less.

In the toner according to the present invention, the volume fraction having a particle size of 15 μm or more is usually 2% or less, preferably 1% or less, more preferably 0.1% or less. Although it is most preferable that there is no coarse powder having a particle size of 15 μm or more, it is difficult in actual production, and it is usually not necessary to make it 0.01% or less.
Further, in the toner according to the present invention, it is desirable that the number fraction having a particle size of 5 μm or less is usually 15% or less, preferably 10% or less because it is effective in improving image fog.

Here, the volume average particle size [D _v ], the number average particle size [D _n ], the volume fraction and the number fraction of the toner can be measured by the following procedure. Use a Coulter Counter Multisizer II or III (manufactured by Beckman Coulter, Inc.) as the toner particle size measurement device, and connect it to an interface that outputs the number distribution / volume distribution and a general personal computer. To do. Further, Isoton II is used as the electrolytic solution. As a measuring method, 0.1 to 5 mL of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 mL of the electrolytic solution, and 2 to 20 mg of a measurement sample (toner) is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and is measured with a multisizer type II or type III of the Coulter counter using a 100 μm aperture. In this way, the number and volume of the toner are measured to calculate the number distribution and the volume distribution, respectively, and the volume average particle diameter [D _v ] and the number average particle diameter [D _n ] are obtained, respectively.

<Physical properties related to the molecular weight of the toner>
At least one of the peak molecular weights in GPC of the THF soluble content of the toner according to the present invention is usually 10,000 or more, preferably 20,000 or more, more preferably 30,000 or more, and usually 150,000 or less, preferably 10 10,000 or less, more preferably 70,000 or less. THF refers to tetrahydrofuran. When the peak molecular weight is lower than the above range, the mechanical durability in the non-magnetic one-component development method may be deteriorated. When the peak molecular weight is higher than the above range, the low temperature fixability and the fixing strength are deteriorated. There is a case.

In addition, the peak molecular weight in GPC of the THF soluble part of the toner according to the present invention is measured under the following conditions using a measuring apparatus: HLC-8120GPC (manufactured by Tosoh Corporation).
That is, the column is stabilized in a heat chamber at 40 ° C., and tetrahydrofuran (THF) as a solvent is allowed to flow through the column at this temperature at a flow rate of 1 mL per minute. Next, the toner is dissolved in THF and filtered through a 0.2 μm filter, and the filtrate is used as a sample.

The measurement is performed by injecting 50 to 200 μL of a THF solution of a resin whose sample concentration (resin concentration) is adjusted to 0.05 to 0.6 mass%. In measuring the molecular weight of the sample (resin component in the toner), the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of the calibration curve created by several monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Manufactured by Toyo Soda Kogyo Co., Ltd. and having molecular weights of 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , It is appropriate to use 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

Furthermore, as a column used in the above measuring method, in order to accurately measure a molecular weight region of 10 ³ to 2 × 10 ⁶ , it is preferable to combine a plurality of commercially available polystyrene gel columns, for example, manufactured by Waters A combination of μ-styrel 500, 103, 104, 105 and a combination of shodex KA801, 802, 803, 804, 805, 806, 807 manufactured by Showa Denko KK are preferable.

  Further, the THF-insoluble content of the toner according to the present invention is usually 10% or more, preferably 20% or more, and usually 60% or less, preferably 50% or less when measured by a gravimetric method using Celite filtration described later. It is. If it is not within the above range, it may be difficult to achieve both mechanical durability and low-temperature fixability.

  The measurement of the insoluble content of tetrahydrofuran (THF) in the toner can be performed by the following procedure. That is, 1 g of a sample (toner) was added to 100 g of THF and allowed to stand at 25 ° C. for 24 hours for dissolution, followed by filtration using 10 g of Celite, and the solvent in the filtrate was distilled off to quantify the THF soluble content. It can be subtracted from 1 g to calculate the THF insoluble matter.

<Softening point and glass transition temperature of toner>
There is no restriction on the softening point [Sp] of the toner according to the present invention, and it is arbitrary as long as the effects of the present invention are not significantly impaired. From the viewpoint of fixing with low energy, the upper limit is usually 150 ° C. or lower, preferably 140 ° C. or lower. It is desirable that From the viewpoint of high temperature offset resistance and durability, the lower limit of the softening point is usually 80 ° C. or higher, preferably 100 ° C. or higher.

  The softening point [Sp] of the toner was measured with a flow tester under the conditions of 1.0 g of a sample of 1 mm × 10 mm nozzle, a load of 30 kg, a preheating time of 50 ° C. for 5 minutes, and a heating rate of 3 ° C./min. The temperature at the midpoint of the strand from the start to the end of the flow can be obtained.

  Further, there is no limitation on the glass transition temperature [Tg] of the toner according to the present invention, and it is optional as long as the effects of the present invention are not significantly impaired. Usually, it is 80 ° C. or lower, preferably 70 ° C. or lower, with low energy. It is desirable because it can be fixed. The glass transition temperature [Tg] is usually 40 ° C. or higher, preferably 50 ° C. or higher, from the viewpoint of blocking resistance.

  The glass transition temperature [Tg] of the toner is obtained by drawing a tangent line at the start of the transition (inflection) of the curve measured with a differential scanning calorimeter at a temperature rising rate of 10 ° C./min. It can be determined as temperature.

  The softening point [Sp] and glass transition temperature [Tg] of the toner are greatly affected by the type and composition ratio of the polymer contained in the toner. Therefore, the softening point [Sp] and the glass transition temperature [Tg] of the toner can be adjusted by appropriately optimizing the type and composition of the polymer. It can also be adjusted by the molecular weight of the polymer, the gel content, the kind of low melting point components such as wax, and the blending amount.

<Wax in toner>
When the toner according to the present invention contains a wax, the dispersed particle diameter of the wax in the toner particles is usually 0.1 μm or more, preferably 0.3 μm or more as an average particle diameter, and the upper limit is usually 3 μm or less. Preferably, it is 1 μm or less. If the dispersed particle diameter of the wax is too small, there is a possibility that the effect of improving the filming resistance of the toner may not be obtained. If the dispersed particle diameter of the wax is too large, the wax is easily exposed on the surface of the toner. And heat resistance may be reduced.

  The dispersed particle diameter of the wax may be determined by observing an electron microscope after slicing the toner, or wax particles remaining on the filter after elution of the toner polymer with an organic solvent or the like in which the wax does not dissolve. Can be confirmed by a method of measuring with a microscope.

  Further, the ratio of the wax in the toner according to the present invention is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.05% by weight or more, preferably 0.1% by weight or more, and usually 20%. It is desirable that the content be not more than wt%, preferably not more than 15 wt%. If the ratio of the wax is too small, the fixing temperature range may be insufficient. If the ratio is too large, the apparatus member may be contaminated and the image quality may be deteriorated.

<Externally added fine particles>
The toner according to the present invention may be used by adding external fine particles to the surface of the toner particles in order to improve the fluidity, charging stability, anti-blocking property at high temperature, and the like.

  As a method for attaching the externally added fine particles to the toner particle surface, for example, in the above-described toner manufacturing method, the secondary aggregate and the externally added fine particles are mixed in a liquid medium and then heated to externally add the toner particles onto the toner particles. Examples include a method of fixing fine particles; a method of mixing or fixing externally added fine particles to toner particles obtained by separating, washing, and drying secondary aggregates from a liquid medium.

  Examples of the mixer used when the toner particles and the externally added fine particles are mixed in a dry type include a Henschel mixer, a super mixer, a nauter mixer, a V-type mixer, a Redige mixer, a double cone mixer, and a drum type mixer. Can be mentioned. In particular, it is preferable to use a high-speed agitation type mixer such as a Henschel mixer or a super mixer, and appropriately mix the mixture by stirring and mixing uniformly by appropriately setting the blade shape, the number of revolutions, the time, the number of times of driving and stopping, and the like.

  In addition, as a device used for fixing toner particles and externally added fine particles in a dry method, a compression shearing device capable of applying compressive shear stress, a particle surface melting processing device capable of melting the particle surface, etc. Is mentioned.

  A compression shearing apparatus generally has a narrow gap formed by a head surface and a head surface, a head surface and a wall surface, or a wall surface and a wall surface that move relative to each other while maintaining a gap. By being forced to pass through the portion, compressive stress and shear stress are applied to the particle surface without substantial pulverization. An example of such a compression shearing apparatus is a mechanofusion apparatus manufactured by Hosokawa Micron.

  On the other hand, the particle surface melting treatment apparatus is generally configured so as to fix the externally added fine particles by instantaneously heating the mixture of the basic fine particles and the externally added fine particles above the melting start temperature of the basic fine particles using a hot air stream or the like. The Examples of such a particle surface melting apparatus include a surfing system manufactured by Nippon Pneumatic Co., Ltd.

  As the externally added fine particles, known fine particles that can be used for this purpose can be used. Examples thereof include inorganic fine particles and organic fine particles.

  Examples of the inorganic fine particles include silicon carbide, boron carbide, titanium carbide, zirconium carbide, hafnium carbide, vanadium carbide, tantalum carbide, niobium carbide, tungsten carbide, chromium carbide, molybdenum carbide, calcium carbide and the like, boron nitride, nitriding Nitride such as titanium, zirconium nitride, silicon nitride, boride such as zirconium boride, silica, colloidal silica, titanium oxide, aluminum oxide, calcium oxide, magnesium oxide, zinc oxide, copper oxide, zirconium oxide, cerium oxide, talc , Oxides and hydroxides such as hydrotalcite, various titanate compounds such as calcium titanate, magnesium titanate, strontium titanate, barium titanate, tricalcium phosphate, calcium dihydrogen phosphate, monohydrogen phosphate calcium Phosphoric compounds such as substituted calcium phosphates in which a portion of the phosphate ions is replaced by anions, sulfides such as molybdenum disulfide, fluorides such as magnesium fluoride and fluorocarbon, aluminum stearate, calcium stearate, stearic acid Various carbon blacks including metal soaps such as zinc and magnesium stearate, talc, bentonite, and conductive carbon black can be used. Furthermore, magnetic substances such as magnetite, maghematite, and an intermediate between magnetite and maghematite may be used.

  On the other hand, as the organic fine particles, for example, styrene resin, acrylic resin such as polymethyl acrylate and polymethyl methacrylate, epoxy resin, melamine resin, tetrafluoroethylene resin, trifluoroethylene resin, polyvinyl chloride, Fine particles such as polyethylene and polyacrylonitrile can be used.

  Among these externally added fine particles, silica, titanium oxide, alumina, zinc oxide, carbon black and the like are particularly preferably used.

  Further, on the surface of these inorganic or organic fine particles, a silane coupling agent, titanate coupling agent, silicone oil, modified silicone oil, silicone varnish, fluorine-based silane coupling agent, fluorine-based silicone oil, amino group or Surface treatment such as hydrophobization may be performed by a treating agent such as a coupling agent having a quaternary ammonium base. In addition, 1 type may be used for a processing agent and it may use 2 or more types together by arbitrary combinations and a ratio.

  In addition, 1 type may be used for an external addition fine particle, and 2 or more types may be used together by arbitrary combinations and a ratio.

  Further, the number average particle diameter of the externally added fine particles is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.001 μm or more, preferably 0.005 μm or more, and usually 3 μm or less, preferably 1 μm or less. Yes, a plurality of those having different average particle diameters may be blended. The average particle diameter of the externally added fine particles can be determined by observation with an electron microscope, conversion from the value of the BET specific surface area, or the like.

  Further, the ratio of the externally added fine particles to the toner according to the present invention is arbitrary as long as the effect of the present invention is not significantly impaired, but as the ratio of the externally added fine particles to the total weight of the toner according to the present invention and the externally added fine particles, Usually 0.1% by weight or more, preferably 0.3% by weight or more, more preferably 0.5% by weight or more, and usually 10% by weight or less, preferably 6% by weight or less, more preferably 4% by weight or less. It is desirable to do. If the amount of the externally added fine particles is too small, the fluidity and the charging stability may be insufficient. If the amount is too large, the fixability may be deteriorated.

<Others>
The charging characteristics of the toner according to the present invention may be negatively charged or positively charged, and can be set according to the method of the image forming apparatus used. The charging characteristics of the toner can be adjusted by the selection and composition ratio of toner base particle components such as a charge control agent, the selection and composition ratio of externally added fine particles, and the like.

  Further, the toner according to the present invention can be used as a one-component developer, or can be mixed with a carrier and used as a two-component developer.

  When the toner according to the present invention is used as a two-component developer, the carrier that forms the developer by mixing with the toner according to the present invention includes, for example, known magnetic substances such as iron powder, ferrite, and magnetite carriers Or, those whose surfaces are coated with a resin coating, magnetic resin carriers, and the like.

  As the carrier coating resin, for example, generally known styrene resins, acrylic resins, styrene acrylic copolymer resins, silicone resins, modified silicone resins, fluorine resins, and the like can be used. Is not to be done.

  The average particle diameter of the carrier is not particularly limited, but those having an average particle diameter of usually 10 μm or more and usually 200 μm are preferable.

  The carrier is preferably used at a ratio of usually 5 parts by weight or more and 100 parts by weight or less with respect to 1 part by weight of the toner.

  The formation of a full-color image by electrophotography can be carried out in a conventional manner using magenta, cyan, and yellow color toners and, if necessary, black toner.

  Hereinafter, the present invention will be described in more detail with reference to synthesis examples, examples and comparative examples. In addition, the following examples are shown in order to explain the present invention in detail, and the present invention is not limited to the following examples unless it is contrary to the gist thereof.

[Powder XRD spectrum measurement and peak half-width calculation conditions]
In addition, the powder X-ray-diffraction spectrum of the phthalocyanines obtained by each synthesis example mentioned later and the comparative synthesis example was measured in the following procedures. That is, as a measuring apparatus, PW1700 manufactured by PANalytical, which is a concentrated optical system powder X-ray diffractometer using CuKα characteristic X-rays (wavelength 1.541１．５) as a radiation source, 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.

The peak half-width was calculated by the profile fitting method. Profile fitting was performed using powder X-ray diffraction pattern analysis software JADE5.0 + manufactured by MDI. The calculation conditions were as follows. That is, the background was fixed at an ideal position from the entire measurement range (2θ = 3.0 to 40.0 °). As the fitting function, a Peason-VII function considering the contribution of CuKα ₂ was used. Three variables of the fitting function were refined: diffraction angle (2θ), peak height, and peak half-value width (β _o ). The influence of CuKα ₂ was removed, and the diffraction angle (2θ), peak height, and peak half-value width (β _o ) derived from CuKα ₁ were calculated. The asymmetry was fixed at 0 and the shape constant was fixed at 1.5.

The peak half-value width (β _o ) calculated by the above profile fitting is the peak half width (2θ = 28.442 °) of the standard Si (NIST Si 640b) calculated by the same measurement conditions and the same profile fitting conditions. By correcting according to the following formula using β _Si ), the peak half-value width (β) derived from the sample was obtained.

[Synthesis Example 1 (β-type oxytitanium phthalocyanine crystal)]
A β-type oxytitanium phthalocyanine crystal was prepared according to the procedure of “Example of production of crude TiOPc” described in JP-A-10-7925 and then “Example 1”. The powder XRD spectrum of the obtained β-type oxytitanium phthalocyanine crystal is shown in FIG. In addition, the chlorine content contained in the obtained β-type oxytitanium phthalocyanine crystal is measured by the method described in the column <Chlorine content measurement conditions (elemental analysis)> in the above [Best Mode for Carrying Out the Invention]. As a result, the chlorine content was 0.20% by weight or less below the lower limit of detection. In addition, the peak of chlorooxytitanium phthalocyanine with respect to oxytitanium phthalocyanine in the β-type oxytitanium phthalocyanine crystal obtained in accordance with the method described in the section <Mass spectrum measurement conditions> of [Best Mode for Carrying Out the Invention] above The intensity ratio was measured and found to be 0.002.

[Synthesis Example 2 (low crystalline oxytitanium phthalocyanine)]
50 parts by weight of β-type oxytitanium phthalocyanine crystal obtained in Synthesis Example 1 was added to 1250 parts by weight of 95% concentrated sulfuric acid cooled to −10 ° C. or lower. At this time, it added slowly so that the internal temperature of a sulfuric acid solution might not exceed -5 degreeC. After completion of the addition, the concentrated sulfuric acid solution was stirred at −5 ° C. or lower for 2 hours. After stirring, the concentrated sulfuric acid solution was filtered through a glass filter, the insoluble matter was filtered off, and then the concentrated sulfuric acid solution was released into 12500 parts by weight of ice water to precipitate oxytitanium phthalocyanine, followed by stirring for 1 hour. After stirring, the solution was filtered off, and the resulting wet cake was washed again in 2500 parts by weight of water for 1 hour and filtered. By repeating this washing operation until the ionic conductivity of the filtrate reached 0.5 mS / m, 452 parts by weight of a low crystalline oxytitanium phthalocyanine wet cake was obtained (oxytitanium phthalocyanine content 11.1% by weight). . FIG. 7 shows a powder XRD spectrum of the obtained low crystalline oxytitanium phthalocyanine crystal.

[Examples 1 to 4, Comparative Synthesis Example 1]
As a phthalocyanine crystal precursor, 33 parts by weight of the low crystalline oxytitanium phthalocyanine wet cake obtained in Synthesis Example 2 was added to 90 parts by weight of water, followed by stirring at room temperature for 30 minutes. Thereafter, 13 parts by weight of each of the compounds shown in the right column of Table 2 was added, and the mixture was further stirred at room temperature for 1 hour. After stirring, water was separated, 80 parts by weight of methanol was added, and the mixture was stirred and washed at room temperature for 1 hour. After washing, the mixture was filtered, and 80 parts by weight of methanol was added again, followed by stirring and washing for 1 hour, followed by filtration and drying by heating in a vacuum dryer to obtain crystals composed of oxytitanium phthalocyanine alone (these are described below). As appropriate, these are referred to as phthalocyanine crystals of Examples 1 to 4 and Comparative Synthesis Example 1.) The powder XRD spectra of the phthalocyanine crystals of Examples 1 to 4 and Comparative Synthesis Example 1 are shown in FIGS. As apparent from the powder XRD spectra of FIGS. 8 to 12, the phthalocyanine crystals of Examples 1 to 4 and Comparative Synthesis Example 1 all have a Bragg angle (2θ ± 0.2) with respect to CuKα characteristic X-rays (wavelength 1.541Å). °) It had a main diffraction peak at 27.2 °.

[Synthesis Example 3 (low crystalline phthalocyanine composition)]
In Synthesis Example 2, 50 parts by weight of the oxytitanium phthalocyanine crystal of Synthesis Example 1 used as a raw material, 47.5 parts by weight of the oxytitanium phthalocyanine crystal of Synthesis Example 1 and metal-free phthalocyanine (Dainippon Ink Chemical Industries, Ltd.) Except for changing to a mixture with 2.5 parts by weight of “Fastgen Blue 8120BS”), 410 parts by weight of a low crystalline phthalocyanine composition wet cake was obtained by performing the same operation as in Synthesis Example 2 (containing phthalocyanines) Rate 12.2% by weight). FIG. 13 shows a powder XRD spectrum of the obtained low crystalline phthalocyanines.

[Examples 5 to 8, Comparative Synthesis Example 2]
As a phthalocyanine crystal precursor, 33 parts by weight of a wet cake of the low crystalline phthalocyanine composition obtained in Synthesis Example 7 was added to 90 parts by weight of water and stirred at room temperature for 30 minutes. Thereafter, 13 parts by weight of each compound shown in the right column of Table 3 was added, and the mixture was further stirred at room temperature for 1 hour. After stirring, water was separated, 80 parts by weight of methanol was added, and the mixture was stirred and washed at room temperature for 1 hour. After washing, the mixture was filtered, and 80 parts by weight of methanol was added again, followed by stirring and washing for 1 hour, followed by filtration and drying by heating in a vacuum dryer to obtain a mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine ( These are referred to as phthalocyanine crystals of Examples 5 to 8 and Comparative Synthesis Example 2, respectively). The powder XRD spectra of the obtained oxytitanium phthalocyanine crystals of Examples 5 to 8 and Comparative Synthesis Example 2 are shown in FIGS. As is apparent from the powder XRD spectra of FIGS. 14 to 18, the oxytitanium phthalocyanine mixed crystals of Examples 5 to 8 and Comparative Synthesis Example 2 are all Bragg angles (2θ ±) with respect to CuKα characteristic X-rays (wavelength 1.541Å). 0.2 °) and had a main diffraction peak at 27.2 °.

[Method for producing photoreceptor]
Using a conductive support in which an aluminum vapor-deposited film (thickness 70 nm) is formed on the surface of a biaxially stretched polyethylene terephthalate resin film (thickness 75 μm), an undercoat layer prepared by the following method on the vapor-deposited layer of the support The coating dispersion was applied with a bar coater so that the film thickness after drying was 1.25 μm or less, and dried to form an undercoat layer.

  The undercoat layer dispersion was prepared by the following method. That is, a rutile type titanium oxide having an average primary particle size of 40 nm (“TTO55N” manufactured by Ishihara Sangyo Co., Ltd.) and 3% by weight of methyldimethoxysilane (“TSL8117” manufactured by Toshiba Silicone Co., Ltd.) with respect to the titanium oxide were flowed at high speed. Disperse the surface-treated titanium oxide obtained by mixing at high speed with a rotary mixing speed of 34.5 m / sec using a ball mill of methanol / 1-propanol. Thus, a dispersion slurry of hydrophobized titanium oxide was obtained. The dispersion slurry, a mixed solvent of methanol / 1-propanol / toluene, and ε-caprolactam [compound represented by the following formula (A)] / bis (4-amino-3-methylcyclohexyl) methane [the following formula (B Compound represented by the following formula (C)] / decamethylene dicarboxylic acid [compound represented by the following formula (D)] / octadecamethylene dicarboxylic acid [in the following formula (E) The compositional molar ratio of the compound represented] is 60% / 15% / 5% / 15% / 5% of the copolymerized polyamide pellets with heating and stirring and mixing to dissolve the polyamide pellets. By performing sonic dispersion treatment, the weight ratio of methanol / 1-propanol / toluene is 7/1/2, and the hydrophobically treated titanium oxide / co-polymer is mixed. Containing a slip polyamide in a weight ratio of 3/1, it was undercoat layer dispersion having a solid concentration of 18.0%.

  On the other hand, 20 parts by weight of each phthalocyanine crystal to be described later was used as a charge generating material, mixed with 280 parts by weight of 1,2-dimethoxyethane, and pulverized with a sand grind mill for 2 hours for atomization dispersion treatment. In addition, a mixture of 253 parts by weight of 1,2-dimethoxyethane and 85 parts by weight of 4-methoxy-4-methyl-2-pentanone was added to polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name “Denkabutyral” # 6000C) 10 parts by weight was dissolved to prepare a binder liquid. A charge generation layer coating liquid was prepared by mixing the above-mentioned finely-treated liquid obtained by the above-described atomization dispersion treatment and the above-described binder liquid and 230 parts by weight of 1,2-dimethoxyethane. This charge generation layer coating solution is applied onto the undercoat layer formed on the conductive support by a bar coater so that the film thickness after drying is 0.4 μm and dried to generate charges. A layer was formed.

  Furthermore, 50 parts by weight of a mixture composed of a compound group of geometric isomers having a structure represented by the following structural formula (F) as a main component, synthesized based on “Example 1” of JP-A-2002-80432 As a charge transport material, and 51 mol% of a repeating unit having 2,2-bis (4-hydroxy-3-methylphenyl) propane represented by the following structural formula (G) as an aromatic diol component, and the following structure: A terminal structural formula derived from pt-butylphenol, comprising 49 mol% of a repeating unit having 1,1-bis (4-hydroxyphenyl) -1-phenylethane represented by the formula (H) as an aromatic diol component In addition, 100 parts by weight of polycarbonate resin having a binder is used as a binder resin, in addition, 8 parts by weight of 2,6-di-t-butyl-4-methylphenol, silicone oil A coating solution A for charge transport layer was prepared by dissolving 0.03 part by weight of a trade name “KF96” (manufactured by Shin-Etsu Chemical Co., Ltd.) in 640 parts by weight of a tetrahydrofuran / toluene (weight ratio 8/2) mixed solvent. . By applying this coating solution for charge transport layer on the resin film provided with the charge generation layer as described above so that the film thickness after drying is 25 μm, and drying to form a charge transport layer. An electrophotographic photosensitive member having a laminated photosensitive layer was prepared.

[Examples 9 to 16, Comparative Examples 1 and 2]
Using the phthalocyanine crystals of Examples 9 to 16 and Comparative Synthesis Examples 1 and 2 as charge generation materials, electrophotographic photoreceptors were produced according to the above-described photoreceptor production method. These are hereinafter referred to as electrophotographic photoreceptors of Examples 9 to 16 and Comparative Examples 1 and 2 as appropriate. Table 4 below shows the correspondence between each electrophotographic photosensitive member, the phthalocyanine crystal used as the charge generation material, and the composition thereof.

[Evaluation of electrophotographic photoreceptor]
An electrophotographic characteristic evaluation apparatus prepared according to the standards of the Electrophotographic Society of the electrophotographic photoreceptors of Examples 9 to 16 and Comparative Examples 1 and 2 ("Basic and Application of Secondary Electrophotographic Technology", edited by the Electrophotographic Society, Corona) , 404-405), and the electrical characteristics were evaluated by carrying out a cycle of charging, exposure, potential measurement, and static elimination according to the following procedure.

  The charger was arranged at -70 °, the exposure device at 0 °, the surface electrometer probe at 36 °, and the static eliminator at an angle of -150 °, and each device was arranged at a distance of 2 mm from the photoreceptor surface. A scorotron charger was used for charging. The exposure lamp used was a halogen lamp JDR110V-85WLN / K7 manufactured by Ushio Electric Co., Ltd., and a monochromatic light of 780 nm using a filter MX0780 manufactured by Asahi Spectroscopic Co., Ltd. 660 nm LED light was used for the static elimination light.

  While rotating the photoconductor at a constant rotation speed (60 rpm), the photoconductor is charged so that the initial surface potential becomes −700 V, and the charged photoconductor surface is passed through an exposure portion where monochromatic light of 780 nm is exposed. Then, the surface potential when it came to the position of the probe of the surface potential meter was measured (100 ms between exposure and potential measurement).

  Subsequently, the surface of the photoreceptor was irradiated with 780 nm monochromatic light through an ND filter while changing the amount of light, and the irradiation energy (exposure energy) when the surface potential was −350 V was measured.

After the photoconductor is left in an NN environment for 8 hours, the value of irradiation energy (exposure energy) (unit: μJ / cm ² ) measured in the NN environment is sometimes referred to as standard humidity sensitivity (hereinafter referred to as “En _1/2 ”). The exposure energy (exposure energy) value (unit: μJ / cm ² ) measured in the NL environment after leaving the photoreceptor in the NL environment for 8 hours is set to a low humidity sensitivity (hereinafter referred to as “El _1/2 ”). It may be said.)

Using the obtained values of standard humidity sensitivity: En _1/2 and low humidity sensitivity: El _1/2 , the sensitivity retention rate due to humidity change was calculated (unit%) by calculating according to the following formula.

  Table 5 below shows the evaluation results of the electrical characteristics of the electrophotographic photoreceptors of Examples 9 to 16 and Comparative Examples 1 and 2.

  The phthalocyanine crystals of Examples 1 to 8 and Comparative Synthesis Examples 1 and 2 used as charge generation materials are all CuKα characteristic X-rays (wavelengths) as apparent from the powder XRD spectra (FIGS. 8 to 12 and 14 to 18). It was a phthalocyanine crystal having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to 1.541 °.

The electrophotographic photoreceptors of Examples 9 to 16 and Comparative Examples 1 and 2 using the phthalocyanine crystals of Examples 1 to 8 and Comparative Synthesis Examples 1 and 2 as the charge generation material were selected according to the composition of the phthalocyanine crystals. Divided into two groups {(crystals consisting of oxytitanium phthalocyanine alone: Examples 9-12, Comparative Example 1) and (mixed crystals of oxytitanium phthalocyanine and metal-free phthalocyanine: Examples 13-16, Comparative Example 2)} When the example and the comparative example are compared for each group, the standard humidity sensitivity El _1/2 is the same for both the example and the comparative example. However, when comparing the values of the sensitivity retention ratios, the electrophotographic photosensitive member of the example has less sensitivity fluctuation with respect to the humidity change than the electrophotographic photosensitive member of the comparative example.

  From the above results, the phthalocyanine crystals of Examples 1 to 4 and Examples 5 to 8 obtained through the step of converting the crystal form by bringing a phthalocyanine crystal precursor into contact with an aromatic aldehyde compound (that is, the present invention) When phthalocyanine crystals were used in electrophotographic photoreceptors, it was found that sensitivity fluctuations with respect to changes in the usage environment can be greatly improved.

[Examples 17 to 22, Comparative Synthesis Examples 3 to 8]
As a phthalocyanine crystal precursor, 38 parts by weight of the low crystalline oxytitanium phthalocyanine wet cake obtained in Synthesis Example 2 was added to 100 parts by weight of water and stirred at room temperature for 30 minutes. Thereafter, 9 ml of each aromatic compound shown in the right column of Table 6 below was added, and the mixture was further stirred at room temperature for 1 hour. After stirring, water was separated, 80 parts by weight of methanol was added, and the mixture was stirred and washed at room temperature for 1 hour. After washing, the mixture was filtered, and 80 parts by weight of methanol was added again, followed by stirring and washing for 1 hour, followed by filtration and drying by heating in a vacuum dryer to obtain crystals composed of oxytitanium phthalocyanine alone (these are described below). The phthalocyanine crystals of Examples 17 to 22 and Comparative Synthesis Examples 3 to 8 are referred to as appropriate). 19 to 30 show powder XRD spectra of the phthalocyanine crystals of Examples 17 to 22 and Comparative Synthesis Examples 3 to 8, respectively. As is clear from the powder XRD spectra of FIGS. 19 to 30, the phthalocyanine crystals of Examples 17 to 22 and Comparative Synthesis Examples 3 to 8 are all Bragg angles (2θ ± 0) with respect to CuKα characteristic X-rays (wavelength 1.541 波長). .2 °) had a main diffraction peak at 27.2 °.

[Examples 23 to 25, Comparative Synthesis Examples 9 to 12]
As a phthalocyanine crystal precursor, 33 parts by weight of a wet cake of the low crystalline phthalocyanine composition obtained in Synthesis Example 3 was added to 90 parts by weight of water and stirred at room temperature for 30 minutes. Thereafter, 9 ml of each aromatic compound shown in the right column of Table 7 was added, and the mixture was further stirred at room temperature for 1 hour. After stirring, water was separated, 80 parts by weight of methanol was added, and the mixture was stirred and washed at room temperature for 1 hour. After washing, the mixture was filtered, and 80 parts by weight of methanol was added again, followed by stirring and washing for 1 hour, followed by filtration and drying by heating in a vacuum dryer to obtain a mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine ( These are referred to as phthalocyanine crystals of Examples 23 to 25 and Comparative Synthesis Examples 9 to 12, respectively). The powder XRD spectra of the obtained oxytitanium phthalocyanine crystals of Examples 23 to 25 and Comparative Synthesis Examples 9 to 12 are shown in FIGS. As is apparent from the powder XRD spectra of FIGS. 31 to 37, the oxytitanium phthalocyanine mixed crystals of Examples 23 to 25 and Comparative Synthesis Examples 9 to 12 are all Bragg angles with respect to CuKα characteristic X-rays (wavelength 1.541Å) ( 2θ ± 0.2 °) having a main diffraction peak at 27.2 °.

[Examples 26 to 34, Comparative Examples 3 to 12]
Using the phthalocyanine crystals of Examples 17 to 25 and Comparative Synthesis Examples 3 to 12 as charge generating materials, electrophotographic photoreceptors were produced according to the above-described photoreceptor production method (hereinafter referred to as Examples 26 to 34 and Comparative Examples as appropriate). 3 to 12 electrophotographic photoreceptors). Tables 8 and 9 below show the correspondence between each electrophotographic photosensitive member and the phthalocyanine crystal used as the charge generation material.

[Evaluation of electrophotographic photoreceptor]
The electrophotographic photoreceptors of Examples 26 to 34 and Comparative Examples 3 to 12 were evaluated for electrical characteristics in the same manner as the evaluations of Examples 9 to 16, and the electrophotographic examples of Examples 26 to 34 and Comparative Examples 3 to 12 were used. The evaluation results of the electrical characteristics of the photoreceptor are shown in Table 8 and Table 9 below. In Table 8 and Table 9 below, Examples and Comparative Examples using phthalocyanine crystals obtained by bringing an aromatic compound having a similar structure into contact with a phthalocyanine crystal precursor are shown side by side.

  As is apparent from the powder XRD spectrum (FIGS. 19 to 37), the phthalocyanine crystals of Examples 17 to 25 and Comparative Synthesis Examples 3 to 12 used as charge generation materials are all CuKα characteristic X-rays (wavelength 1.541Å). It was a phthalocyanine crystal having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 °.

The compositions of the phthalocyanine crystals using the electrophotographic photosensitive members of Examples 26 to 34 and Comparative Examples 3 to 12 using the phthalocyanine crystals of Examples 17 to 25 and Comparative Synthesis Examples 3 to 12 as charge generation materials, and 8 sets (Examples 26 and 27 and Comparative Example 3; Examples 28 and 4; Example 29 and Comparative Example 5) depending on the structure of the aromatic compound used for the crystal conversion treatment in producing the phthalocyanine crystal Example 30 and Comparative Example 6; Example 31 and Comparative Examples 7 and 8; Example 32 and Comparative Example 9; Example 33 and Comparative Example 10; Example 34 and Comparative Examples 11 and 12) When the example and the comparative example are compared, it can be seen that the electrophotographic photosensitive member of the example has a higher standard humidity sensitivity En _1/2 than the electrophotographic photosensitive member of the comparative example.

From the above results, the phthalocyanine crystals of Examples 17 to 25 obtained through the step of converting the crystal form by bringing the phthalocyanine crystal precursor into contact with the specific substituent-containing aromatic compound (that is, the phthalocyanine crystal of the present invention). It has been clarified that a high standard humidity sensitivity En _1/2 can be obtained when used in an electrophotographic photoreceptor.

[Examples 35 to 68, Comparative Synthesis Examples 13 to 14]
As a phthalocyanine crystal precursor, 40 parts by weight of the low crystalline oxytitanium phthalocyanine wet cake obtained in Synthesis Example 2 was added to 90 parts by weight of water and stirred at room temperature for 30 minutes. Thereafter, 9 ml of each of the contact treatment liquids of Examples 35 to 68 shown in Table 10 below (a solution in which a specific organic acid compound was mixed with a non-acidic organic compound at a predetermined concentration) was added, and the mixture was further stirred at room temperature for 1 hour. After stirring, water was separated, 80 parts by weight of methanol was added, and the mixture was stirred and washed at room temperature for 1 hour. After washing, the mixture was filtered, and 80 parts by weight of methanol was added again, followed by stirring and washing for 1 hour, followed by filtration and drying by heating in a vacuum dryer to obtain crystals composed of oxytitanium phthalocyanine alone (these are described below). The phthalocyanine crystals of Examples 35 to 68 are referred to as appropriate).

  Further, in the above Examples 35 to 68, instead of the contact treatment liquids of Examples 35 to 68, the contact treatment liquids (liquids composed only of non-acidic organic compounds) of Comparative Synthesis Examples 13 and 14 shown in Table 11 below. A crystal composed of oxytitanium phthalocyanine alone was obtained by carrying out the same operations as in Examples 35 to 68 except that 9 ml was used (hereinafter referred to as phthalocyanine crystals of Comparative Synthesis Examples 13 and 14 as appropriate).

  With respect to the phthalocyanine crystals of Examples 35 to 68 and Comparative Synthesis Examples 13 and 14, powder XRD spectra were measured. Each of the obtained powder XRD spectra had a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to the CuKα characteristic X-ray (wavelength 1.541Å). When the non-acidic organic compound used was the same, a powder X-ray diffraction spectrum having substantially the same shape was obtained regardless of the presence or absence of the specific organic acid compound. As representative examples, powder XRD spectra of phthalocyanine crystals obtained in Examples 35, 64, 65, 67, and 68 are shown in FIGS. 38 to 42, respectively.

[Example 69]
40 parts by weight of the low crystalline oxytitanium phthalocyanine (phthalocyanine crystal precursor) obtained in Synthesis Example 2 is dissolved in 15 ml of 3-chlorobenzoic acid (specific organic acid compound) in 100 ml of tetrahydrofuran (non-acidic organic compound). In addition to the solution (contact treatment liquid of Example 69 shown in Table 10 below), the mixture was stirred at room temperature for 3 hours. After stirring, the mixture was filtered and dried by heating with a vacuum dryer to obtain a crystal composed of oxytitanium phthalocyanine alone (hereinafter, referred to as phthalocyanine crystal of Example 69 as appropriate). The powder XRD spectrum of the phthalocyanine crystal of Example 69 is shown in FIG. As is clear from FIG. 43, the powder XRD spectrum of the phthalocyanine crystal of Synthesis Example 37 has a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to the CuKα characteristic X-ray (wavelength 1.541Å). I had it.

[Comparative Synthesis Example 15]
In Example 69 described above, except that 100 ml of tetrahydrofuran was used instead of the tetrahydrofuran solution of 3-chlorobenzoic acid, a crystal consisting of oxytitanium phthalocyanine alone was obtained by performing the same operation as in Example 69 (this) Hereinafter referred to as phthalocyanine crystal of Comparative Synthesis Example 15 as appropriate). When the powder XRD spectrum of the phthalocyanine crystal of Comparative Synthesis Example 6 was measured, the obtained powder XRD spectrum was almost the same shape as the powder XRD spectrum of the phthalocyanine crystal of Example 69 (FIG. 43).

[Examples 70 to 74]
As a phthalocyanine crystal precursor, 33 parts by weight of a wet cake of the low crystalline phthalocyanine composition obtained in Synthesis Example 3 was added to 90 parts by weight of water and stirred at room temperature for 30 minutes. Thereafter, 9 ml of each of the contact treatment liquids of Examples 70 to 74 shown in Table 11 below (a solution obtained by mixing a specific organic acid compound with a non-acidic organic compound at a predetermined concentration) was added, and the mixture was further stirred at room temperature for 1 hour. After stirring, water was separated, 80 parts by weight of methanol was added, and the mixture was stirred and washed at room temperature for 1 hour. After washing, the mixture was filtered, and 80 parts by weight of methanol was added again, followed by stirring and washing for 1 hour, followed by filtration and drying by heating in a vacuum dryer to obtain a mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine ( These are referred to as phthalocyanine crystals of Examples 70 to 74, respectively.)

  For the phthalocyanine crystals of Examples 70 to 74, powder XRD spectra were measured. Each of the obtained powder XRD spectra had a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to the CuKα characteristic X-ray (wavelength 1.541Å). In addition, these powder X-ray diffraction spectra were almost the same shape. As a typical example, a powder XRD spectrum of the phthalocyanine crystal obtained in Example 70 is shown in FIG.

[Examples 75 to 114]
Using the phthalocyanine crystals of Examples 35 to 74 as charge generating materials, electrophotographic photoreceptors were produced according to the above-described photoreceptor production method (hereinafter referred to as electrophotographic photoreceptors of Examples 75 to 114 as appropriate). Tables 12 and 13 below show the correspondence between each electrophotographic photosensitive member, the phthalocyanine crystal used as the charge generation material, and the composition thereof.

[Evaluation of electrophotographic photoreceptor]
The electrophotographic photoreceptors of Examples 75 to 114 and Comparative Examples 13 to 15 were evaluated for electrical characteristics in the same manner as the evaluations of Examples 9 to 16, and the electrophotographic examples of Examples 75 to 114 and Comparative Examples 13 to 15 were evaluated. The evaluation results of the sensitivity retention rate for the photoreceptor are shown in Table 12 and Table 13 below. In Table 12 and Table 13 below, Examples and Comparative Examples using phthalocyanine crystals obtained using the same non-acidic organic compound are shown side by side.

When the electrophotographic photoreceptors of Examples 75 to 114 and Comparative Examples 13 to 15 using the phthalocyanine crystals of Examples 35 to 74 and Comparative Synthesis Examples 13 to 15 as charge generating materials were compared, the results of Comparative Examples 14 and 15 were compared. The electrophotographic photoreceptor was inferior to the standard humidity sensitivity En _1/2 and also inferior in sensitivity retention. Further, the electrophotographic photosensitive member of Comparative Example 13 had a standard humidity sensitivity En _1/2 substantially equal to that of the electrophotographic photosensitive member of the example. The electrophotographic photosensitive member of the example using the phthalocyanine crystal obtained by contacting with the organic acid compound is compared with the electrophotographic photosensitive member of the comparative example using the phthalocyanine crystal obtained by contacting only the non-acidic organic compound. It can be seen that the sensitivity fluctuation with respect to the change in humidity is smaller than that in FIG.

[Examples 115 and 116]
In the above-mentioned [Method for producing photoreceptor], when preparing the coating solution for the charge generation layer, instead of 20 parts by weight of each phthalocyanine crystal of each of the above-mentioned Examples and Comparative Synthetic Examples as a charge-generating substance, Example An electrophotographic photosensitive member was manufactured according to the above-mentioned [Method for manufacturing photosensitive member] except that 20 parts by weight of phthalocyanine crystals and 1.25 parts by weight of 3-chlorobenzoic acid were used in combination. This is hereinafter referred to as the electrophotographic photoreceptor of Example 115 as appropriate.

  Further, an electrophotographic photosensitive member was produced according to the same procedure as in Example 115 except that 1.25 parts by weight of trimellitic organic acid anhydride was used instead of 1.25 parts by weight of 3-chlorobenzoic acid. This is hereinafter referred to as the electrophotographic photoreceptor of Example 116 as appropriate.

For the electrophotographic photoreceptors of Examples 115 and 116, the electrical characteristics were evaluated according to the same procedures as those of the electrophotographic photoreceptors of Examples 9 to 16 and Comparative Examples 1 and 2 described above.
The evaluation results of the electrical characteristics of the electrophotographic photosensitive members of Examples 79, 86, 115, and 116 are shown in Table 14 below.

  From the above results, it can be seen that the effect of improving the sensitivity and suppressing the fluctuation of the sensitivity to the humidity change in the use environment is small only by adding the above-mentioned specific organic acid compound at the time of preparing the charge generation layer coating solution.

[Examples 117 to 131]
As a phthalocyanine crystal precursor, 40 parts by weight of the low crystalline oxytitanium phthalocyanine wet cake obtained in Synthesis Example 2 was added to 100 parts by weight of water, followed by stirring at room temperature for 30 minutes. Thereafter, 9 ml of each of the contact treatment liquids of Examples 117 to 131 shown in Table 15 below (a solution obtained by mixing a non-acidic specific organic compound with an electron-withdrawing specific aromatic compound at a predetermined concentration) was added, and further stirred at room temperature for 1 hour. did. After stirring, water was separated, 80 parts by weight of methanol was added, and the mixture was stirred and washed at room temperature for 1 hour. After washing, the mixture was filtered, and 80 parts by weight of methanol was added again, followed by stirring and washing for 1 hour, followed by filtration and drying by heating in a vacuum dryer to obtain crystals composed of oxytitanium phthalocyanine alone (these are described below). The phthalocyanine crystals of Examples 117 to 131 are referred to as appropriate).

  The powder XRD spectrum was measured about the phthalocyanine crystal | crystallization of Examples 117-131. Each of the obtained powder XRD spectra had a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to the CuKα characteristic X-ray (wavelength 1.541Å). When the non-acidic specific organic compound used was the same, a powder X-ray diffraction spectrum having substantially the same shape was obtained regardless of the presence or absence of the electron-withdrawing specific aromatic compound. As representative examples, powder XRD spectra of the phthalocyanine crystals obtained in Examples 128 to 131 are shown in FIGS. 45 to 48, respectively.

[Example 132]
40 parts by weight of the low crystalline oxytitanium phthalocyanine (phthalocyanine crystal precursor) wet cake obtained in Synthesis Example 2 is dissolved in 15 ml of phthalide (electron-withdrawing specific aromatic compound) in 100 ml of tetrahydrofuran (non-acidic specific organic compound). In addition to the mixed solution (contact treatment liquid of Example 132 shown in Table 15 below), the mixture was stirred at room temperature for 3 hours. After stirring, the mixture was filtered and dried by heating with a vacuum dryer to obtain a crystal composed of oxytitanium phthalocyanine alone (hereinafter, referred to as a phthalocyanine crystal of Example 132 as appropriate). A powder XRD spectrum of the phthalocyanine crystal of Example 132 is shown in FIG. As is clear from FIG. 49, the powder XRD spectrum of the phthalocyanine crystal of Example 132 has a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to the CuKα characteristic X-ray (wavelength 1.541Å). I had it.

[Examples 133 to 136]
As a phthalocyanine crystal precursor, 33 parts by weight of a wet cake of the low crystalline phthalocyanine composition obtained in Synthesis Example 3 was added to 90 parts by weight of water and stirred at room temperature for 30 minutes. Thereafter, 9 ml of each of the contact treatment liquids of Examples 133 to 136 shown in Table 16 below (a solution in which an electron-withdrawing specific aromatic compound was mixed at a predetermined concentration with 3-chlorobenzaldehyde which is a non-acidic specific organic compound) was added, The mixture was further stirred at room temperature for 1 hour. After stirring, water was separated, 80 parts by weight of methanol was added, and the mixture was stirred and washed at room temperature for 1 hour. After washing, the mixture was filtered, and 80 parts by weight of methanol was added again, followed by stirring and washing for 1 hour, followed by filtration and drying by heating in a vacuum dryer to obtain a mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine ( These are referred to as phthalocyanine crystals of Examples 133 to 136, respectively.)

  A powder XRD spectrum was measured for the phthalocyanine crystals of Examples 133 to 136. Each of the obtained powder XRD spectra had a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to the CuKα characteristic X-ray (wavelength 1.541Å). In addition, these powder X-ray diffraction spectra were almost the same shape. As a representative example, a powder XRD spectrum of the phthalocyanine crystal obtained in Example 133 is shown in FIG.

[Examples 137 to 156]
Using the phthalocyanine crystals of Examples 117 to 136 as charge generating materials, electrophotographic photoreceptors were produced according to the above [Photoreceptor Production Method] (these are hereinafter referred to as electrophotographic photoreceptors of Examples 137 to 156 as appropriate). Tables 17 and 18 below show the correspondence between each electrophotographic photosensitive member, the phthalocyanine crystal used as the charge generation material, and its composition.

[Evaluation of electrophotographic photoreceptor]
The electrical characteristics of the electrophotographic photosensitive members of Examples 137 to 156 and Comparative Examples 13 to 15 were evaluated according to the same procedure as in the evaluation of the electrophotographic photosensitive members of Examples 9 to 16. Tables 17 and 18 below show the evaluation results of the sensitivity retention ratios of the electrophotographic photosensitive members of Examples 137 to 156 and Comparative Examples 13 to 15. In Table 17 and Table 18 below, Examples and Comparative Examples using phthalocyanine crystals obtained using the same non-acidic organic compound are shown side by side.

When comparing the electrophotographic photoreceptors of Examples 137 to 156 and Comparative Examples 13 to 15 using the phthalocyanine crystals of Examples 117 to 136 and Comparative Synthesis Examples 13 to 15 as charge generating materials, the results of Comparative Examples 14 and 15 were compared. The electrophotographic photoreceptor was inferior to the standard humidity sensitivity En1 _{/ 2} . The electrophotographic photosensitive member of Comparative Example 13 had a standard humidity sensitivity En _1/2 substantially equal to that of the electrophotographic photosensitive member of the example. The electrophotographic photosensitive member of the example using the phthalocyanine crystal obtained by contact with the specific aromatic compound was compared with the electron of the comparative example using the phthalocyanine crystal obtained by contacting only the non-acidic specific organic compound. It can be seen that the sensitivity fluctuation with respect to the humidity change is small and more preferable than the photographic photoreceptor.

[Examples 157 and 158]
In the fine dispersion treatment step in preparing the coating solution for charge generation layer in the above-mentioned [Method for producing photoreceptor], 20 parts by weight of the phthalocyanine crystal of Example 1 is used as the charge generation material, and 1.25 wt. Of phthalide. The electrophotographic photosensitive member was manufactured in accordance with the above-described [Method of manufacturing photosensitive member] except that the above parts were used together. Hereinafter, this is referred to as an electrophotographic photoreceptor of Example 157 as appropriate.

  Further, an electrophotographic photosensitive member was produced in the same manner as in Example 157 except that 1.25 parts by weight of 2-sulfobenzoic anhydride was used instead of 1.25 parts by weight of phthalide. This is hereinafter referred to as the electrophotographic photoreceptor of Example 158 as appropriate.

  For the electrophotographic photoreceptors of Examples 157 and 158, the electrical characteristics were evaluated according to the same procedure as in the evaluation of the electrophotographic photoreceptors of Examples 9 to 16. The evaluation results are shown in Table 19 below.

  From the above results, the above-described effects (sensitivity improvement and sensitivity to changes in humidity in the use environment) of the phthalocyanine crystal of the present invention can be obtained only by adding the above-mentioned electron-withdrawing specific aromatic compound during the preparation of the coating solution for the charge generation layer. It was found that the fluctuation suppressing effect was small.

[Example 159]
A cylinder made of an aluminum alloy having an outer diameter of 30 mm, a length of 350 mm, and a wall thickness of 1.0 mm, whose surface is roughly cut (R _max = 1.2), is anodized, and then sealed with nickel acetate as a main component. By performing sealing treatment with a pore agent, an anodic oxide coating (alumite coating) of about 6 μm was formed.

  This cylinder was dip-coated in the charge generation layer forming coating solution previously prepared in Example 87 to form a charge generation layer so that the film thickness after drying was 0.4 μm. Next, it has 51 mol% of repeating units represented by the structural formula (G) and 49 mol% of repeating units represented by the structural formula (H), and has a terminal structural formula derived from pt-butylphenol. 100 parts by weight of a polycarbonate resin (viscosity average molecular weight 49200), 50 parts by weight of a mixture comprising a compound group of geometric isomers, the main component of which is the structure represented by the formula (F), and BHT (3, 3) as an antioxidant 5 parts by weight of 5-di-t-butyl-4-hydroxytoluene), 0.05 part by weight of silicone oil as a leveling agent, and 640 parts by weight of a mixed solvent of tetrahydrofuran and toluene (80% by weight of tetrahydrofuran, 20% by weight of toluene). The coating solution for forming a charge transport layer was prepared by mixing with the part. The cylinder formed with the charge generation layer prepared earlier was dip-coated in this charge transport layer forming coating solution, and a 35 μm thick charge transport layer after drying was provided to prepare an electrophotographic photoreceptor. This is referred to as an electrophotographic photosensitive member of Example 159.

[Example 160]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the thickness of the charge transport layer was changed to 30 μm. This is referred to as an electrophotographic photoreceptor of Example 160.

[Example 161]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the thickness of the charge transport layer was 25 μm. This is referred to as an electrophotographic photoreceptor of Example 161.

[Example 162]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the thickness of the charge transport layer was 20 μm. This is referred to as an electrophotographic photosensitive member of Example 162.

[Example 163]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the thickness of the charge transport layer was changed to 15 μm. This is referred to as an electrophotographic photosensitive member of Example 163.

[Example 164]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the charge generation layer forming coating solution prepared in Example 105 was used instead of the charge generation layer forming coating solution used in Example 159. This is referred to as an electrophotographic photosensitive member of Example 164.

[Example 165]
An electrophotographic photosensitive member was produced in the same manner as in Example 164 except that the thickness of the charge transport layer was changed to 30 μm. This is referred to as an electrophotographic photosensitive member of Example 165.

[Example 166]
An electrophotographic photosensitive member was produced in the same manner as in Example 164 except that the thickness of the charge transport layer was 25 μm. This is referred to as an electrophotographic photosensitive member of Example 166.

[Example 167]
An electrophotographic photosensitive member was produced in the same manner as in Example 164 except that the thickness of the charge transport layer was 20 μm. This is referred to as an electrophotographic photosensitive member of Example 167.

[Example 168]
An electrophotographic photosensitive member was produced in the same manner as in Example 164 except that the thickness of the charge transport layer was changed to 15 μm. This is referred to as an electrophotographic photoreceptor of Example 168.

[Example 169]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the charge generation layer forming coating solution prepared in Example 97 was used instead of the charge generation layer forming coating solution used in Example 159. This is referred to as an electrophotographic photosensitive member of Example 169.

[Example 170]
An electrophotographic photosensitive member was produced in the same manner as in Example 169 except that the thickness of the charge transport layer was changed to 30 μm. This is referred to as an electrophotographic photoreceptor of Example 170.

[Example 171]
An electrophotographic photosensitive member was produced in the same manner as in Example 169 except that the thickness of the charge transport layer was 25 μm. This is referred to as an electrophotographic photosensitive member of Example 171.

[Example 172]
An electrophotographic photosensitive member was produced in the same manner as in Example 169 except that the thickness of the charge transport layer was 20 μm. This is referred to as an electrophotographic photoreceptor of Example 172.

[Example 173]
An electrophotographic photosensitive member was produced in the same manner as in Example 169 except that the thickness of the charge transport layer was changed to 15 μm. This is referred to as an electrophotographic photoreceptor of Example 173.

[Example 174]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the charge generation layer forming coating solution prepared in Example 79 was used instead of the charge generation layer forming coating solution used in Example 159. This is referred to as an electrophotographic photoreceptor of Example 174.

[Example 175]
An electrophotographic photosensitive member was produced in the same manner as in Example 174 except that the thickness of the charge transport layer was changed to 30 μm. This is referred to as an electrophotographic photosensitive member of Example 175.

[Example 176]
An electrophotographic photosensitive member was produced in the same manner as in Example 174 except that the thickness of the charge transport layer was 25 μm. This is referred to as an electrophotographic photoreceptor of Example 176.

[Example 177]
An electrophotographic photosensitive member was produced in the same manner as in Example 174 except that the thickness of the charge transport layer was 20 μm. This is referred to as an electrophotographic photoreceptor of Example 177.

[Example 178]
An electrophotographic photosensitive member was produced in the same manner as in Example 174 except that the thickness of the charge transport layer was changed to 15 μm. This is referred to as an electrophotographic photosensitive member of Example 178.

[Example 179]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the charge generation layer forming coating solution prepared in Example 145 was used instead of the charge generation layer forming coating solution used in Example 159. This is referred to as an electrophotographic photoreceptor of Example 179.

[Example 180]
An electrophotographic photosensitive member was produced in the same manner as in Example 179 except that the thickness of the charge transport layer was changed to 30 μm. This is referred to as an electrophotographic photoreceptor of Example 180.

[Example 181]
An electrophotographic photosensitive member was produced in the same manner as in Example 179 except that the thickness of the charge transport layer was 25 μm. This is referred to as an electrophotographic photoreceptor of Example 181.

[Example 182]
An electrophotographic photosensitive member was produced in the same manner as in Example 179 except that the thickness of the charge transport layer was 20 μm. This is referred to as an electrophotographic photosensitive member of Example 182.

[Example 183]
An electrophotographic photosensitive member was produced in the same manner as in Example 179 except that the thickness of the charge transport layer was changed to 15 μm. This is referred to as an electrophotographic photoreceptor of Example 183.

[Example 184]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the charge generation layer forming coating solution prepared in Example 144 was used instead of the charge generation layer forming coating solution used in Example 159. This is referred to as an electrophotographic photoreceptor of Example 184.

[Example 185]
An electrophotographic photosensitive member was produced in the same manner as in Example 184 except that the thickness of the charge transport layer was changed to 30 μm. This is referred to as an electrophotographic photoreceptor of Example 185.

[Example 186]
An electrophotographic photosensitive member was produced in the same manner as in Example 184, except that the thickness of the charge transport layer was 25 μm. This is referred to as an electrophotographic photosensitive member of Example 186.

[Example 187]
An electrophotographic photosensitive member was produced in the same manner as in Example 184 except that the thickness of the charge transport layer was 20 μm. This is referred to as an electrophotographic photoreceptor of Example 187.

[Example 188]
An electrophotographic photosensitive member was produced in the same manner as in Example 184 except that the thickness of the charge transport layer was changed to 15 μm. This is referred to as an electrophotographic photosensitive member of Example 188.

[Example 189]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the charge generation layer forming coating solution prepared in Example 9 was used instead of the charge generation layer forming coating solution used in Example 159. This is referred to as an electrophotographic photoreceptor of Example 189.

[Example 190]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the charge generation layer forming coating solution prepared in Example 26 was used instead of the charge generation layer forming coating solution used in Example 159. This is referred to as an electrophotographic photoreceptor of Example 190.

[Comparative Example 16]
An electrophotographic photosensitive member was produced in the same manner as in Example 159 except that the charge generation layer forming coating solution prepared in Comparative Example 15 was used instead of the charge generation layer forming coating solution used in Example 159. . This is referred to as an electrophotographic photosensitive member of Comparative Example 16.

[Comparative Example 17]
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 16 except that the thickness of the charge transport layer was 30 μm. This is referred to as an electrophotographic photosensitive member of Comparative Example 17.

[Comparative Example 18]
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 16 except that the thickness of the charge transport layer was 25 μm. This is referred to as an electrophotographic photoreceptor of Comparative Example 18.

[Comparative Example 19]
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 16 except that the thickness of the charge transport layer was 20 μm. This is referred to as an electrophotographic photoreceptor of Comparative Example 19.

[Comparative Example 20]
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 16 except that the thickness of the charge transport layer was 15 μm. This is referred to as an electrophotographic photosensitive member of Comparative Example 20.

[Evaluation of electrophotographic photoreceptor]
The half-exposure amounts E _1/2 of the electrophotographic photoreceptors obtained in Examples 159 to 190 and Comparative Examples 16 to 20 are as follows using a commercially available photoreceptor evaluation device (Cynthia 55, manufactured by Gentec Corporation). Measurements were made in a static manner according to the procedure described.

  The charger is placed at an angle of 0 °, the exposure device and the surface potential meter probe at 90 °, and the static eliminator at an angle of 270 ° so that the distance from the photoreceptor surface is 2 mm. In a dark place, a scorotron charger set to discharge in a dark place so that the surface potential of the photosensitive member is about −700 V, temperature 25 ° C. ± 2 ° C., relative humidity 50% rh ± 5% The photoreceptor after standing for 8 hours in this environment was charged by passing through the surface of the photoreceptor at a constant rotational speed (30 rpm).

When the surface of the photoreceptor after charging reaches the probe position, it is stopped. After 2.5 seconds from the stop, the monochromatic light of 780 nm having the intensity of 0.15 μW / cm ² obtained from the attached spectral light source system POLAS 34 is obtained. Irradiation was performed for 7.5 seconds, and the exposure amount required until the surface potential of the photoconductor became −550 V to −275 V was measured. The photosensitive member was rotated again, and the entire surface was neutralized with a static eliminator, and then the same operation was performed. This cycle was repeated 6 times, and the measured values of the exposure dose of 5 times except the first were averaged, and the obtained average value was defined as a half exposure dose E _1/2 (μJ / cm ² ). The measurement results are shown in Table 20 and Table 21 below.

  Next, the photosensitive member is placed in an electrophotographic characteristic evaluation apparatus ["Basic and Application of Secondary Electrophotographic Technology" (edited by Electrophotographic Society, published by Corona, pages 404 to 405)] prepared in accordance with the standard of the Electrophotographic Society. After mounting, the electrical characteristics were evaluated by a cycle of charging, exposure, potential measurement, and static elimination.

  The charger was arranged at -70 °, the exposure device at 0 °, the surface electrometer probe at 36 °, and the static eliminator at an angle of -150 °, and each device was arranged at a distance of 2 mm from the photoreceptor surface. A scorotron charger was used for charging. The exposure lamp was a monochromatic light of 780 nm using a halogen lamp JDR110V-85WLN / K7 manufactured by Ushio Electric Co., Ltd. and a filter MX0780 manufactured by Asahi Spectroscopic Co., Ltd. 660 nm LED light was used for the static elimination light.

  The initial surface potential of the photoconductor is −700 V while rotating the photoconductor at a constant rotation speed (60 rpm) after being left in an environment of temperature 25 ° C. ± 2 ° C. and relative humidity 50% rh ± 5% for 8 hours. The surface potential was measured when the surface of the charged photoreceptor was exposed to the 780 nm monochromatic light and reached the probe position of the surface potential meter (100 ms between exposure and potential measurement). .

The 780 nm monochromatic light was passed through an ND filter to change the amount of light, the exposure amount was irradiated in the range of 0 to 10 times the half exposure amount E _1/2 , and the surface potential at each exposure amount was measured. . This operation is performed in an environment having a temperature of 25 ° C. ± 2 ° C. and a relative humidity of 50% rh ± 5% (ordinary temperature and humidity environment; hereinafter referred to as “NN environment”). The post-exposure potential (hereinafter sometimes referred to as “V _NN ”) was measured.

Thereafter, the photosensitive member is left in an environment at a temperature of 25 ° C. ± 2 ° C. and a relative humidity of 10% rh ± 5% for 8 hours, and then the environment at a temperature of 25 ° C. ± 2 ° C. and a relative humidity of 10% rh ± 5% (room temperature and low humidity). The same operation is performed in the environment (hereinafter sometimes referred to as “NL environment”), and the post-exposure potential in the NL environment at each exposure amount (hereinafter also referred to as “V _NL ”) is measured. It was.

Absolute value of the difference between the potential after exposure V _NL at potential V _NN and NL environment after exposure under NN environment at the same exposure (| V _NN -V _NL |) is calculated, and environmental change the maximum value The dependency amounts are shown in Table 20 and Table 21 below.

An image was formed using each electrophotographic photosensitive member, and image evaluation was performed by the following evaluation method.
The electrophotographic photosensitive member was mounted on a cartridge for a digital copying machine DIALTA Di350 manufactured by Minolta, and the cartridge was mounted on the copying machine. The copier is left in an environment of 35 ° C. ± 2 ° C. and a relative humidity of 83% rh ± 5% for 24 hours, and further in an environment of a temperature of 5 ° C. ± 2 ° C. and a relative humidity of 10% rh ± 5% After leaving for 5 hours, a halftone image was printed. Based on the printed image, the appearance of black streaks generated in one cycle of the electrophotographic photosensitive member was compared.
The copier is a device that charges an electrophotographic photosensitive member with a scorotron charger and develops it with a two-component contact development system, and black streaks are likely to occur.

From the results of Table 20 and Table 21, the following can be understood.
The electrophotographic photoreceptors of Examples 159 to 190 have a half-exposure amount En _1/2 smaller than that of the photoreceptors of the respective comparative examples when compared with the same film thickness, are highly sensitive, and have an amount of environmental variation dependency. small. Further, when the image was formed by a contact developing type image forming apparatus equipped with these electrophotographic photosensitive members and the image characteristics were evaluated, black stripes were seen in the electrophotographic photosensitive members of the respective comparative examples. On the other hand, it was not seen in the electrophotographic photosensitive member of each example.

  From the above, the electrophotographic photoreceptors of Examples 159 to 190 have high sensitivity and small fluctuations in characteristics with respect to humidity fluctuations, and further, process cartridges and image formation on which these electrophotographic photoreceptors are mounted. It became clear that the device can provide high quality images without image defects against environmental changes.

[Example 191]
Polycarbonate resin 100 having a terminal structural formula derived from pt-butylphenol, comprising 51 mol% of the repeating unit represented by the structural formula (G) and 49 mol% of the repeating unit represented by the structural formula (H). 640 parts by weight of a mixed solvent prepared by mixing 50 parts by weight of a charge transport material represented by the following structural formula (I-1) and 0.05 parts by weight of silicone oil in a weight ratio of 8: 2. A charge transport layer coating solution was prepared by dissolving in the part.

  In Example 9, an electrophotographic photosensitive member was produced in the same manner as in Example 9 except that the charge transport layer coating solution prepared by the above method was used. This is referred to as an electrophotographic photoreceptor of Example 191.

[Example 192]
Electrophotography was conducted in the same manner as in Example 191 except that the compound represented by the following structural formula (I-2) was used instead of the compound represented by the above structural formula (I-1) used in Example 191. A photoconductor was prepared. This is referred to as an electrophotographic photoreceptor of Example 192.

[Example 193]
In the same manner as in Example 191, except that the compound represented by the following structural formula (I-3) was used instead of the compound represented by the above structural formula (I-1) used in Example 191, an electrophotographic process was performed. A photoconductor was prepared. This is referred to as an electrophotographic photosensitive member of Example 193.

[Example 194]
Instead of the compound represented by the structural formula (I-1) used in Example 191, the weight of the compound represented by the following structural formula (I-4a) and the compound represented by the following structural formula (I-4b) A mixture having a ratio of 1/1 was used so that the total weight was the same as the weight of the compound represented by the structural formula (I-1) used in Example 191, and the charge generation used in Example 9 was further performed. An electrophotographic photosensitive member was produced in the same manner as in Example 191 except that the charge generation layer coating solution used in Example 87 was used instead of the layer coating solution. This is referred to as an electrophotographic photoreceptor of Example 194.

[Example 195]
Instead of the mixture of the compound of the above structural formula (I-4a) and the compound of the above structural formula (I-4b) used in Example 194, the compound represented by the following structural formula (I-5a) and the following structural formula ( A mixture having a weight ratio of 1/1 of the compound represented by I-5b), the total weight of which is represented by the compound represented by the structural formula (I-4a) and the structural formula (I-4b) used in Example 194. An electrophotographic photosensitive member was produced in the same manner as in Example 194, except that the total weight of the mixture of the compounds to be used was the same. This is referred to as an electrophotographic photoreceptor of Example 195.

[Example 196]
In place of the mixture of the compound of the above structural formula (I-4a) and the compound of the above structural formula (I-4b) used in Example 194, a compound represented by the following structural formula (I-6) was prepared in Example 194. The same operation as in Example 194 was performed, except that the total weight of the compound represented by the structural formula (I-4a) and the compound represented by the structural formula (I-4b) was used. Then, an electrophotographic photosensitive member was produced. This is referred to as an electrophotographic photoreceptor of Example 196.

[Example 197]
In Example 196, the same procedure as in Example 196 was used except that a polycarbonate resin composed of a repeating structural unit represented by the following structural formula (I-7) was used instead of the polycarbonate resin used in the coating solution for the charge transport layer. The operation was carried out to produce an electrophotographic photoreceptor. This is referred to as an electrophotographic photoreceptor of Example 197.

[Example 198]
In Example 196, instead of the polycarbonate resin used in the charge transport layer coating solution, a binder resin composed of a repeating structural unit represented by the following structural formula (I-8) was used, and the structural formula (I-6) In the same manner as in Example 196 except that a mixture consisting of a compound group of geometric isomers having the structure represented by the structural formula (F) as a main component instead of the compound represented by the structural formula (F) was used. A photographic photoreceptor was prepared. This is referred to as an electrophotographic photoreceptor of Example 198.

[Example 199]
Instead of the binder resin composed of the repeating structural unit represented by the structural formula (I-8) used in Example 198, the binder resin composed of the repeating structural unit represented by the following structural formula (I-9) was used. An electrophotographic photosensitive member was produced in the same manner as in Example 198 except that the charge generation layer coating solution used in Example 79 was used as the charge generation layer coating solution. This is referred to as an electrophotographic photoreceptor of Example 199.

[Example 200]
In Example 198, the same procedure as in Example 198 was used except that a binder resin composed of a repeating structural unit represented by the following structural formula (I-10) was used instead of the binder resin used in the charge transport layer coating solution. The operation was carried out to produce an electrophotographic photoreceptor. This is referred to as an electrophotographic photosensitive member of Example 200.

[Example 201]
Instead of the charge generation layer coating solution used in Example 198, the charge generation layer coating solution used in Example 97 was used as a binder resin for the charge transport layer coating solution, and the following structural formula (I-11) An electrophotographic photosensitive member was produced in the same manner as in Example 198 except that a compound composed of a repeating structural unit represented by the following formula was used. This is referred to as an electrophotographic photoreceptor of Example 201.

[Example 202]
The same operation as in Example 201 except that a polycarbonate resin composed of a repeating structural unit represented by the following structural formula (I-12) was used in place of the binder resin in the coating solution for charge transport layer used in Example 201. Then, an electrophotographic photosensitive member was produced. This is referred to as an electrophotographic photosensitive member of Example 202.

[Comparative Example 21]
An electrophotographic photosensitive member was produced in the same manner as in Example 191 except that the charge generation material of the coating solution for charge generation layer used in Example 191 was replaced with the compound obtained in Comparative Synthesis Example 1. did. This is referred to as an electrophotographic photosensitive member of Comparative Example 21.

[Comparative Example 22]
An electrophotographic photosensitive member was produced in the same manner as in Example 192 except that the charge generation material of the charge generation layer coating solution used in Example 192 was replaced with the compound obtained in Comparative Synthesis Example 1. did. This is referred to as an electrophotographic photosensitive member of Comparative Example 22.

[Measurement of characteristics of electrophotographic photosensitive member]
For the electrophotographic photoreceptors of Examples 191 to 202 and Comparative Examples 21 and 22, according to the same procedure as the electrophotographic photoreceptors of Examples 9 to 16, the half-exposure amount in a standard humidity environment and a low humidity environment was measured, and the humidity change Sensitivity retention (%) was obtained. The results are shown in Table 22 below.

  From the results shown in Table 22, the electrophotographic photosensitive member of the present invention has little variation in sensitivity to humidity changes in the usage environment even if it has a photosensitive layer using various charge transport materials and various binder resins. I understand.

The phthalocyanine crystal of the present invention has an advantage that it has a high sensitivity and has a small variation in sensitivity to changes in humidity in the usage environment. Therefore, it can be suitably used as a material (particularly a charge generating substance) such as a solar cell, electronic paper, and electrophotographic photosensitive member.
The electrophotographic photosensitive member, the electrophotographic photosensitive member cartridge, and the image forming apparatus of the present invention are preferably used in various fields such as copying machines, printers, faxes, and other various electrophotographic devices using electrophotographic technology. Can do.

1 is a schematic diagram illustrating a main configuration of an embodiment of an image forming apparatus of the present invention. The example of the powder X-ray-diffraction spectrum of low crystalline phthalocyanines is shown. The example of the powder X-ray-diffraction spectrum of low crystalline phthalocyanines is shown. The example of the powder X-ray-diffraction spectrum of amorphous phthalocyanines is shown. The example of the powder X-ray-diffraction spectrum of amorphous phthalocyanines is shown. 3 is a powder XRD spectrum of β-type oxytitanium phthalocyanine crystal obtained in Synthesis Example 1. FIG. 3 is a powder XRD spectrum of the low crystalline oxytitanium phthalocyanine obtained in Synthesis Example 2. 2 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 1. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 2. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 3. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 4. 3 is a powder XRD spectrum of a phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Comparative Synthesis Example 1. 4 is a powder XRD spectrum of the low crystalline phthalocyanine composition (composition containing oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Synthesis Example 3. 6 is a powder XRD spectrum of the phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Example 5. 6 is a powder XRD spectrum of the phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Example 6. 7 is a powder XRD spectrum of the phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Example 7. 4 is a powder XRD spectrum of the phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Example 8. 4 is a powder XRD spectrum of a phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Comparative Synthesis Example 2. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 17. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 18. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 19. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 20. 2 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 21. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 22. 4 is a powder XRD spectrum of a phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Comparative Synthesis Example 3. 7 is a powder XRD spectrum of a phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Comparative Synthesis Example 4. 7 is a powder XRD spectrum of a phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Comparative Synthesis Example 5. 7 is a powder XRD spectrum of a phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Comparative Synthesis Example 6. 7 is a powder XRD spectrum of a phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Comparative Synthesis Example 7. 7 is a powder XRD spectrum of a phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Comparative Synthesis Example 8. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 23. 4 is a powder XRD spectrum of the phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Example 24. 6 is a powder XRD spectrum of the phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Example 25. 7 is a powder XRD spectrum of a phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Comparative Synthesis Example 9. 4 is a powder XRD spectrum of a phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Comparative Synthesis Example 10. 7 is a powder XRD spectrum of a phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Comparative Synthesis Example 11. 7 is a powder XRD spectrum of a phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Comparative Synthesis Example 12. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 35. 6 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 64. 7 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 66. 7 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 67. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 68. 7 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 69. 4 is a powder XRD spectrum of a phthalocyanine crystal (mixed crystal of oxytitanium phthalocyanine and metal-free phthalocyanine) obtained in Example 70. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 128. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 129. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 130. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 131. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 132. 4 is a powder XRD spectrum of the phthalocyanine crystal (crystal of oxytitanium phthalocyanine alone) obtained in Example 133.

Explanation of symbols

1 Photoconductor (Electrophotographic photoconductor)
2 Charging device (charging roller; charging unit)
3 Exposure equipment (exposure section)
4 Development device (development unit)
5 Transfer device 6 Cleaning device (cleaning part)
7 Fixing Device 41 Developing Tank 42 Agitator 43 Supply Roller 44 Developing Roller 45 Regulating Member 71 Upper Fixing Member (Fixing Roller)
72 Lower fixing member (fixing roller)
73 Heating device T Toner P Recording paper (paper, medium)

Claims (18)

  A phthalocyanine crystal obtained by a step of converting a crystal form by bringing a phthalocyanine crystal precursor into contact with an aromatic aldehyde compound.   Bringing a phthalocyanine crystal precursor into contact with an organic compound having no acidic functional group in the presence of at least one compound selected from the group consisting of an organic acid, an organic acid anhydride, and an organic acid ester having a heteroatom. A phthalocyanine crystal obtained by a step of converting the crystal type by   Organic that is solid under conditions of 1013 hPa and 25 ° C., is in a liquid state under conditions of 1013 hPa and 25 ° C., and has no functional group that exhibits acidity in the presence of an aromatic compound having an electron-withdrawing substituent A phthalocyanine crystal obtained by a step of converting a crystal form by bringing a compound into contact with a phthalocyanine crystal precursor.   A phthalocyanine obtained by a step of converting a crystal form by bringing a phthalocyanine crystal precursor into contact with a group containing an oxygen atom and an aromatic compound having a halogen atom having an atomic weight of 30 or more as a substituent. crystal.   The phthalocyanine crystal according to claim 4, wherein the group containing an oxygen atom is a group selected from the group consisting of an organic group having a carbonyl group, a nitro group, and an ether group.   The phthalocyanine crystal according to any one of claims 1 to 5, wherein the step of converting the crystal form of phthalocyanine is performed in the presence of water.   The phthalocyanine crystal according to claim 1, comprising at least oxytitanium phthalocyanine.   It has a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to CuKα characteristic X-rays (wavelength 1.541Å), according to claim 1. Phthalocyanine crystals.   An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer contains the phthalocyanine crystal according to any one of claims 1 to 8. In an electrophotographic photosensitive member having a photosensitive layer with a film thickness of 35 ± 2.5 μm on a conductive support, the half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh satisfies the following formula (1): In addition, when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half exposure amount E _1/2 is 0 times or more and 10 times or less. An electrophotographic photosensitive member, wherein the absolute value of the difference in surface potential at the same exposure amount is less than 50 V within the range of the exposure amount.
E _1/2 ≦ 0.059 (1)
(In the above formula (1), E _1/2 represents the exposure amount of light having a wavelength of 780 nm (μJ) required to attenuate the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V. / Cm ² ) In an electrophotographic photosensitive member having a photosensitive layer with a thickness of 30 ± 2.5 μm on a conductive support, a half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh satisfies the following formula (2): In addition, when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half exposure amount E _1/2 is 0 times or more and 10 times or less. An electrophotographic photosensitive member, wherein the absolute value of the difference in surface potential at the same exposure amount is less than 50 V within the range of the exposure amount.
E _1/2 ≦ 0.061 (2)
(In the above formula (2), E _1/2 represents the exposure amount of light having a wavelength of 780 nm (μJ) required to attenuate the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V. / Cm ² ) In an electrophotographic photosensitive member having a photosensitive layer with a film thickness of 25 ± 2.5 μm on a conductive support, the half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh satisfies the following formula (3): In addition, when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half exposure amount E _1/2 is 0 times or more and 10 times or less. An electrophotographic photosensitive member, wherein the absolute value of the difference in surface potential at the same exposure amount is less than 50 V within the range of the exposure amount.
E _1/2 ≦ 0.066 (3)
(In the above formula (3), E _1/2 is the exposure amount of light having a wavelength of 780 nm (μJ required for attenuating the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V) / Cm ² ) In an electrophotographic photosensitive member having a photosensitive layer with a thickness of 20 ± 2.5 μm on a conductive support, a half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh satisfies the following formula (4): In addition, when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half exposure amount E _1/2 is 0 times or more and 10 times or less. An electrophotographic photosensitive member, wherein the absolute value of the difference in surface potential at the same exposure amount is less than 50 V within the range of the exposure amount.
E _1/2 ≦ 0.079 (4)
(In the above formula (4), E _1/2 is the exposure amount of light having a wavelength of 780 nm (μJ required for attenuating the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V) / Cm ² ) In an electrophotographic photosensitive member having a photosensitive layer with a film thickness of 15 ± 2.5 μm on a conductive support, a half-exposure amount E _{1/2 at} a temperature of 25 ° C. and a relative humidity of 50% rh satisfies the following formula (5): In addition, when the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 50% rh is compared with the light attenuation curve at a temperature of 25 ° C. and a relative humidity of 10% rh, the half exposure amount E _1/2 is 0 times or more and 10 times or less. An electrophotographic photosensitive member, wherein the absolute value of the difference in surface potential at the same exposure amount is less than 50 V within the range of the exposure amount.
E _1/2 ≦ 0.090 (5)
(In the above formula (5), E _1/2 is the exposure amount of light having a wavelength of 780 nm (μJ) required to attenuate the absolute value | V ₀ | of the surface potential V ₀ of the photoreceptor from 550 V to 275 V. / Cm ² )   15. The electrophotographic photosensitive member according to claim 10, wherein the photosensitive layer contains oxytitanium phthalocyanine.   The electrophotographic photosensitive member according to any one of claims 10 to 15, wherein the photosensitive layer contains the phthalocyanine crystal according to any one of claims 1 to 8.   An electrophotographic photosensitive member according to any one of claims 10 to 16, a charging unit that charges the electrophotographic photosensitive member, an exposure unit that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image, An electrophotographic photosensitive member cartridge comprising: a developing unit that develops an electrostatic latent image formed on the electrophotographic photosensitive member; and a cleaning unit that cleans the electrophotographic photosensitive member.   An electrophotographic photosensitive member according to any one of claims 10 to 16, a charging unit that charges the electrophotographic photosensitive member, an exposure unit that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image, And an image forming apparatus comprising: a developing unit that develops the electrostatic latent image formed on the electrophotographic photosensitive member.

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