JP5470739B2 - Electrophotographic photosensitive member, image forming apparatus, and electrophotographic cartridge - Google Patents

Description

  The present invention relates to an electrophotographic photosensitive member, an image forming apparatus, and an electrophotographic cartridge.

  Conventionally, inorganic photoconductive substances such as selenium, cadmium sulfide, and zinc oxide have been widely used as materials for electrophotographic photoreceptors (hereinafter, simply referred to as “photoreceptors” as appropriate). On the other hand, since the organic photoconductive substance is excellent in film formability, it is possible to easily produce a photoconductor, for example, by coating on a support. Therefore, a photoconductor using an organic photoconductive substance is excellent in productivity, and the organic photoconductive substance is very useful as a material for an inexpensive photoconductor. Furthermore, a photoreceptor using an organic photoconductive substance has an advantage that color sensitivity can be freely controlled, for example, by selecting dyes and pigments to be used. In view of this, a wide range of studies have been made on photoreceptors using organic photoconductive substances (organic photoreceptors).

  In recent years, a functional separation type (laminated layer) in which a charge generation layer containing, for example, an organic photoconductive dye or a pigment, and a charge transport layer containing, for example, an organic photoconductive substance such as a photoconductive polymer or a low molecular weight compound are laminated. Type) photoreceptors have been developed. In the function-separated type photoconductor, the sensitivity and durability, which are the problems of the conventional organic photoconductor, are remarkably improved. Among them, the azo pigment preferably contained in the charge generation layer exhibits excellent photoconductivity with respect to a white light source such as a halogen lamp. Therefore, organic photoconductive substances having various characteristics can be easily obtained depending on the combination of the amine component and the coupler component, and many have been proposed so far (see, for example, Patent Document 1).

  Furthermore, recently, there is a growing need for ultra-high image quality of output images. Therefore, blue to purple (specifically, the emission wavelength is usually 380 nm to 500 nm, hereinafter referred to as “blue (purple)” as appropriate), a beam formed on the photoreceptor using a semiconductor laser as an exposure light source. It has been proposed to reduce the spot diameter (see, for example, Patent Document 2). However, this technique usually requires a photoreceptor having a certain sensitivity or more with respect to a blue (purple) light source. In order to effectively use the irradiated light, the photoconductor is usually required to have high spectral sensitivity in the wavelength range of the exposure light source.

  As an azo pigment corresponding to such a blue (purple) light source, a technique using an anthraquinone azo pigment (for example, see Patent Document 3), a technique using an azo pigment (for example, Patent Document 4, Patent Document 5, and Patent Document) 6) has been proposed.

  Further, for example, copying machines, printers, and the like are required to have higher image quality such as higher resolution and higher gradation performance in addition to stability in image formation in which there are few image defects. Therefore, in order to improve the image quality, a toner having a narrow particle size distribution with an average particle size of about 3 to 8 μm is usually used.

  Conventionally, toner has been produced mainly by a melt-kneading pulverization method in which a binder resin and a colorant are melt-kneaded until uniform and then pulverized. However, in the melt-kneading pulverization method, it has been difficult to efficiently produce toner that can cope with high image quality.

  Therefore, for example, a technique for producing a toner by a polymerization method that generates toner particles in a wet medium has been proposed. For example, Patent Document 3 describes a toner manufactured by a suspension polymerization method. For example, Patent Document 4 describes a toner produced by an emulsion polymerization aggregation method. Among them, the emulsion polymerization aggregation method is a method for producing a toner by aggregating polymer resin fine particles and a colorant in a liquid medium. In this method, the particle size and the circularity of the toner can be adjusted by controlling the aggregation conditions, and thus there is an advantage that various performances of the toner can be easily optimized.

  For example, in order to improve releasability, low-temperature fixability, high-temperature offset property, filming resistance, etc., a method of incorporating a low softening point substance (wax) into the toner has been proposed. When a toner is manufactured using a conventional melt-kneading pulverization method, the amount of the low softening point substance contained in the toner is usually about 5% by weight or less with respect to the binder resin. On the other hand, it is described that a toner produced using a polymerization method can contain a low softening point substance in a large amount (specifically, 5 wt% to 30 wt% or less) (for example, Patent Document 7 and Patent Document 8).

JP-A-3-68953 Japanese Patent Laid-Open No. 9-240051 Japanese Patent Laid-Open No. 10-239956 JP 2002-14482 A JP 2002-131951 A JP 2000-105478 A Japanese Patent Laid-Open No. 5-88409 Japanese Patent Laid-Open No. 11-143125

  However, the photoreceptors described in Patent Documents 3 to 6 do not necessarily have sufficient sensitivity to a blue (purple) light source such as a blue (violet) semiconductor laser.

  Therefore, in order to ensure sufficient sensitivity for a blue (purple) light source, it has been studied to output an image with the light amount extremely increased. However, in such a case, the endurance potential fluctuation tends to be large, and there is a problem that the photoconductor may need to have sufficient endurance in order to output a stable super high-quality image. Was. Further, the conventional photoreceptor has various problems such as a decrease in reliability, an increase in cost, and a decrease in light source life, with respect to the output stability of the light source. Furthermore, there is a limit to the power of the light source, and the photoconductor cannot always ensure proper sensitivity.

  In addition, when an image is formed using the toner described in Patent Documents 7 and 8, high image quality is usually obtained. However, since the fogging phenomenon of the obtained image is also likely to occur, it has been difficult to achieve high resolution, high gradation, and low fog at a high level in the conventional technique.

  The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a photoconductor having a low residual potential with respect to a light source that emits monochromatic light having a wavelength of 380 nm to 500 nm, and a high resolution, An object of the present invention is to provide an image forming apparatus and an electrophotographic cartridge capable of forming a high quality image represented by high gradation and the like, and capable of forming an image with few defects developed faithfully with respect to high resolution exposure. .

  As a result of intensive studies to solve the above problems, the present inventors have used a photoconductor having a photosensitive layer containing a specific azo compound, to a light source that emits monochromatic light having a wavelength of 380 nm to 500 nm. It is possible to form a photoreceptor having a low residual potential, and a high quality image represented by high resolution, high gradation, and the like, and an image with few defects developed faithfully for high resolution exposure. It has been found that an image forming apparatus and an electrophotographic cartridge can be provided, and the present invention has been completed.

That is, the gist of the present invention includes an electrophotographic photosensitive member, a charging unit for charging the electrophotographic photosensitive member, an exposure unit for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, and a toner. An image forming apparatus comprising: a developing unit that develops the formed electrostatic latent image with the toner; and a transfer unit that transfers the toner to a transfer target. It has a photosensitive layer containing a compound represented by (1), and forming an electrostatic latent image by exposing the electrophotographic photoreceptor by the following monochromatic light wavelength 380nm or 500 nm, the image forming apparatus (Claim 1).
(In the formula (1),
Ar ¹ and Ar ² each independently represent an arylene group which may have a substituent, X represents a linking group having 3 to 25 atoms,
n ¹ represents an integer of 0 or 1,
Cp ₁ will have a hydroxyl group, having the structure represented by any one or more of the following formulas (3) to (6), represents the number 50 following organic group having a carbon
Z1 represents a divalent aromatic hydrocarbon group or nitrogen-containing heterocyclic group which may have a substituent,
Rn represents a substituent having 2 to 20 atoms .
Ar ¹ and Ar ² may be cross-linked with each other. )
(In the formulas (3) to (6), Z1 and Rn represent the same as Z1 and Rn in the formula (1). Z2 and Z3 each independently have 30 or less carbon atoms having a ring structure. Z4 represents an organic group having at least one OH group and having a ring structure and having 30 or less carbon atoms, wherein R ² , R ³ and R ⁴ each independently represent a halogen atom, a hydrogen atom And a nitrile group, or an optionally substituted group selected from the group consisting of an alkyl group, an aryl group and an alkoxy group, n ² represents an integer of 0 or 1.)

At this time, the average circularity measured by a flow type particle image analyzer of the toner is preferably 1.000 or less than 0.940 (claim 2).

Further, the toner may satisfy all of the following (i) ~ (iii) (claim 3).
(I) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 μm or less.
(Ii) The average circularity is 0.93 or more.
(Iii) The relationship between the volume median diameter (Dv50) of the toner and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50). Fulfill.

Further, in the toner, the relationship between the volume median diameter (Dv50) and the number% (Dns) of the toner having a particle diameter of 2.00 μm or more and 3.56 μm or less preferably satisfies the following formula (iii-1) ( Claim 4 ).

Further, in the toner, the relationship between the volume median diameter (Dv50) and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm preferably satisfies the following formula (iii-2) ( Claim 5 ).

At this time, the toner is preferably a toner produced in a wet medium (claim 6).

Further, the toner preferably has a resin coating layer (claim 7).

According to another aspect of the present invention, there is provided a cartridge case for detachably supporting the electrophotographic photosensitive member to the image forming apparatus according to claim 1 or 2, and the electrophotographic photosensitive member. wherein, lies in an electrophotographic cartridge (claim 8).

In this case, the average circularity measured by a flow type particle image analyzer of the toner is preferably 1.000 or less than 0.940 (claim 9).

At this time, it is preferable that the toner satisfies all of the following (i) to (iii) (claim 10 ).
(I) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 μm or less.
(Ii) The average circularity is 0.93 or more.
(Iii) The relationship between the volume median diameter (Dv50) of the toner and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50). Fulfill.

  According to the present invention, for a light source that emits monochromatic light having a wavelength of 380 nm to 500 nm, the photosensitive member has a low residual potential, and has high quality typified by high resolution, high gradation, and the like. It is possible to provide an image forming apparatus and an electrophotographic cartridge capable of forming an image with few defects developed faithfully with respect to a resolution exposure.

  Hereinafter, the embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and may be arbitrarily modified and implemented without departing from the spirit of the present invention. it can.

The electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member used in an image forming apparatus for forming an electrostatic latent image by exposing an electrophotographic photosensitive member with monochromatic light having a wavelength of 380 nm to 500 nm. It has a photosensitive layer containing the compound represented by 1). Therefore, the electrophotographic photosensitive member of the present invention is not limited to other configurations as long as the photosensitive layer contains a compound represented by the following formula (1).
(In formula (1), Ar ¹ and Ar ² each independently represent an arylene group which may have a substituent, X represents a linking group having 3 to 25 atoms, and n ¹ is 0. Or an integer of ₁ , Cp ₁ represents an organic group having 50 or less carbon atoms having a hydroxyl group, and Z1 represents a divalent aromatic hydrocarbon group or a nitrogen-containing heterocyclic group which may have a substituent. , Rn represents a substituent, and Ar ¹ and Ar ² may be cross-linked with each other.)

  First, the compound represented by the formula (1) (hereinafter referred to as “compound (1)” as appropriate) will be described.

[1. Compound represented by Formula (1)]
[1-1. Construction]
<Arylene Ar ¹ and Ar ² >
In formula (1), Ar ¹ and Ar ² each independently represent an arylene group which may have a substituent. The number of carbon atoms Ar ¹ and Ar ² have is arbitrary as long as the effects of the present invention are not significantly impaired, but each is usually 6 or more, and the upper limit is usually 20 or less, preferably 16 or less, more preferably. Is 10 or less. When Ar ¹ and Ar ² have too many carbon atoms, the stability of the compound (1) may be reduced. In addition, when Ar < ¹ > and / or Ar < ² > are substituted by the substituent mentioned later, it is preferable that all the carbon numbers including carbon number which a substituent has satisfy | fill said range.

In addition, the molecular weights of Ar ¹ and Ar ² are arbitrary as long as the effects of the present invention are not significantly impaired, but are each independently usually 76 or more, and the upper limit is usually 350 or less, preferably 250 or less, more preferably. Is 150 or less. When the molecular weights of Ar ¹ and Ar ² are too large, the stability of the compound (1) may be reduced. In addition, when Ar < ¹ > and / or Ar < ² > are substituted by the substituent mentioned later, it is preferable that the whole molecular weight including the molecular weight of a substituent satisfy | fill said range.

  Any arylene group can be used as long as the effects of the present invention are not significantly impaired. For example, the arylene group includes a phenylene group, a naphthylene group, a pyrenylene group, a phenanthrene group, and the like. Among these, as the arylene group, a phenylene group is preferable, and among the phenylene groups, a p-phenylene group is more preferable. An arylene group may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

When a p-phenylene group is used as the arylene group, both Ar ¹ and Ar ² do not necessarily need to be p-phenylene groups, and only one of Ar ¹ or Ar ² may be a p-phenylene group. . However, from the viewpoint of improving electric characteristics, it is particularly preferable that at least Ar ¹ is a p-phenylene group.

Ar ¹ and Ar ² may each independently have a substituent. However, when the number of atoms of the substituent is too large, the electrical properties of the compound (1) may be affected. Therefore, the number of atoms of the substituent is preferably 20 or less, and more preferably 10 or less.

Specific examples of the substituent that Ar ¹ and Ar ² may have include a hydroxyl group, an alkyl group, an alkoxy group, an aryl group, an arylthio group, and a halogen atom.
Examples of the alkyl group include a methyl group, an ethyl group, and a propyl group.
Examples of the alkoxy group include a methoxy group, an ethoxy group, and a propoxy group.
Examples of the aryl group include a phenyl group and a naphthyl group.
Examples of the arylthio group include a phenylthio group.
Examples of the halogen atom include a fluorine atom and a chlorine atom.
In addition, as for a substituent, 1 type may be substituted independently and 2 or more types may be substituted by arbitrary ratios and combinations.

In addition, when Ar ¹ and Ar ² have an alkyl group, the alkyl group may be independently a straight chain or a branched chain. Further, it may be a chain or a ring. Furthermore, it may have only a saturated bond or may have an unsaturated bond.

  The above substituents may be further substituted with, for example, an alkyl group such as a methyl group; a halogen atom such as a fluorine atom or a chlorine atom.

In the above formula (1), the nitrogen atom constituting the azo moiety (bonding moiety represented by —N═N—) can be bonded to any carbon atom of Ar ¹ . However, a carbon atom on Ar ¹ bonded to the nitrogen atom constituting the azo site (in the case of ^{n 1 = 0, Ar 2)} X , which will be described later with the carbon atom on Ar ¹ which is bound to, next preferably not position, it is preferred that one or two sandwiching position carbon atom on Ar ^1. This is because the adjacent position takes a structure with a large strain, which may adversely affect the electrical characteristics. Further, the nitrogen atom constituting the other azo moiety in the above formula (1) can also be bonded to any carbon atom of Ar ² , and among them, the nitrogen atom has the same positional relationship as Ar ^1. And a carbon atom are preferably bonded.

In addition to X, Ar ¹ and Ar ² may be cross-linked to form a ring structure. Further, when n ¹ = 0, Ar ¹ and Ar ² are directly bonded to each other, but separately from the bond, they may be cross-linked to form a ring structure.

In addition to the bond included in the structure represented by the above formula (1), when Ar ¹ and Ar ² are bonded to each other to form a ring structure, the newly formed bond is Ar ¹ and Ar ² . May be bonded directly or may contain a linking group. Especially, it is preferable that the newly formed bond includes a linking group. That is, it is preferable that Ar ¹ and Ar ² are bonded via a linking group and are cross-linked to form a ring structure.

  The linking group is arbitrary as long as the effects of the present invention are not significantly impaired. Among them, those having an atom number of usually 10 or less, preferably 8 or less, more preferably 6 or less are desirable. When the linking group has too many atoms, the stability of the compound (1) may be lowered. Moreover, the carbon number which a coupling group has is 0 or more normally, Preferably it is 1 or more, and the upper limit is 8 or less normally, Preferably it is 6 or less, More preferably, it is 4 or less. When there are too many carbon numbers, stability of a compound (1) may fall.

  Specific examples of the linking group include a carbonyl group (representing a divalent —C (═O) —), a sulfinyl group, a sulfonyl group, a sulfinato group, an alkylene group, an alkylidene group, an oxy group, a seleno group, a thio group, and the like. And preferably a carbonyl group or an alkylene group. One linking group may be used alone, or two or more linking groups may be used in any ratio and combination.

Furthermore, the linking group may have a substituent. The type of the substituent is arbitrary as long as the effects of the present invention are not significantly impaired, and examples thereof include a substituent that can be substituted with Ar ¹ and / or Ar ² .

<Linking group X>
In the above formula (1), X represents a linking group for linking Ar ¹ and Ar ² . The number of atoms of the linking group X is usually 3 or more, preferably 4 or more, more preferably 5 or more, and the upper limit is usually 25 or less, preferably 15 or less, more preferably 10 or less. If the linking group X has too many atoms, the electrical characteristics may be affected. When the linking group X is substituted with a substituent described later, the total number of atoms including the number of atoms of the substituent preferably satisfies the above range.

  The molecular weight of the linking group X is usually 25 or more, preferably 50 or more, more preferably 65 or more, and the upper limit is usually 400 or less, preferably 250 or less, more preferably 150 or less. If the molecular weight of the linking group X is too large, the electrical characteristics may be affected. In addition, when the coupling group X is substituted with a substituent described later, it is preferable that the entire molecular weight including the molecular weight of the substituent satisfies the above range.

Specific examples of the linking group X include a group having a heterocyclic ring, a group having an aromatic ring (hereinafter referred to as “aromatic ring” as appropriate), a group having a condensed polycycle, and an aliphatic hydrocarbon group. group _{having, -S (O) 2 -,} - N (CH 3) -, - N (O) -, and the like. In addition, the coupling group X may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

  When the linking group X is a group having a heterocyclic ring, the linking group X preferably has at least one atom selected from the group consisting of nitrogen, oxygen and sulfur. Specifically, examples of the linking group X include a divalent group having an indole ring, a divalent group having an oxazole ring, a divalent group having an isoxazole ring, a divalent group having an oxadiazole ring, and a thiophene ring. A divalent group having a heteroaryl ring such as a divalent group having a divalent group is preferred. Among these, as the linking group X, a divalent group having an oxadiazole ring is more preferable.

  When the linking group X is a group having an aromatic ring, the arylene group is preferable as the aromatic ring, and among the arylene groups, a phenylene group, a naphthylene group, an anthrylene group, and a phenanthrylene group are preferable. Especially, as an aromatic ring, a phenylene group and a naphthylene group are more preferable.

  When the linking group X is a group having a condensed polycycle, the condensed polycycle is preferably tetralin, azulene or fluorene, more preferably tetralin or fluorene.

When the linking group X is a group having an aliphatic hydrocarbon group, the aliphatic hydrocarbon group is preferably an alkylene group, an alkenylene group, an alkynylene group or an alkylidene group.
When the linking group X is an alkylene group, an alkylene group having usually 1 or more, preferably 2 or more, and usually 9 or less, preferably 6 or less is desirable.
When the linking group X is an alkenylene group, an alkenylene group having 2 or more carbon atoms, preferably 2 or more, and usually 9 or less, preferably 6 or less, more preferably 4 or less is desirable.
When the linking group X is an alkynylene group, an alkynylene group having 2 or more carbon atoms, preferably 2 or more, and usually 9 or less, preferably 6 or less, more preferably 4 or less is desirable.
When the linking group X is an alkylidene group, an alkylidene group whose carbon number is usually 2 or more, preferably 3 or more, and usually 9 or less, preferably 6 or less is desirable.

  The linking group X may be linear or branched. Further, it may be a chain or a ring. Furthermore, it may have only a saturated bond or may have an unsaturated bond.

  The linking group X may have a substituent. The number of substituents may be one, or two or more substituents may be used in any ratio and combination. The kind of the substituent is not limited, and examples thereof include an alkyl group, an aryl group, and an alkoxy group.

Among the above linking groups X, from the viewpoint of electrical properties, a linking group having a heterocyclic ring containing a nitrogen atom and an oxygen atom is preferable, a linking group having an oxadiazole ring is more preferable, and is represented by the following formula (2). An oxadiazole ring is particularly preferred.

<Integer n ¹ >
In the above formula (1), n ¹ represents 0 or an integer of 1. When n ¹ = 0, it represents that Ar ¹ and Ar ² are directly bonded. Further, from the viewpoint of electrical properties of the compound (1), it is preferred that n ¹ is 1.

<Atomic group Z>
Z is an atom having a ring structure bonded to a naphthalene skeleton composed of two benzene rings (hereinafter, simply referred to as “naphthalene skeleton” as appropriate) existing in the right part of the structure represented by the above formula (1). Represents a group. Specifically, the atomic group Z has one of the structures described below.

(Z1)
In formula (1), Z1 represents a divalent aromatic hydrocarbon group or a nitrogen-containing heterocyclic group which may have a substituent, and two bonds of Z1 are bonded to separate nitrogen atoms. It has a ring structure.
The carbon number of the divalent aromatic hydrocarbon group is usually 6 or more, and the upper limit is usually 16 or less, preferably 10 or less, more preferably 8 or less. If the number of carbon atoms is too large, the electrical characteristics may be affected. In addition, when a bivalent aromatic hydrocarbon group is substituted by the substituent mentioned later, it is preferable that the whole carbon number including carbon number of a substituent satisfy | fill said range.

  The molecular weight of the divalent aromatic hydrocarbon group is usually 76 or more, and its upper limit is usually 250 or less, preferably 180 or less, more preferably 150 or less. If the molecular weight is too large, the electrical properties may be affected. In addition, when a bivalent aromatic hydrocarbon group is substituted by the substituent mentioned later, it is preferable that the whole molecular weight including the molecular weight of a substituent satisfy | fill said range.

  Specific examples of the divalent aromatic hydrocarbon group include a phenylene group and a naphthylene group, and a phenylene group is particularly preferable.

  The carbon number of the divalent nitrogen-containing heterocyclic group is usually 4 or more, preferably 5 or more, and the upper limit is usually 12 or less, preferably 9 or less. If the number of carbon atoms is too large, the electrical characteristics may be affected. In addition, when a bivalent nitrogen-containing heterocyclic group is substituted with the substituent mentioned later, it is preferable that the whole carbon number including carbon number of a substituent satisfy | fill said range.

  The molecular weight of the divalent nitrogen-containing heterocyclic group is usually 77 or more, and the upper limit is usually 200 or less, preferably 180 or less, more preferably 150 or less. If the molecular weight is too large, the electrical properties may be affected. In addition, when a bivalent nitrogen-containing heterocyclic group is substituted with the substituent mentioned later, it is preferable that the whole molecular weight including the molecular weight of a substituent satisfy | fill said range.

  Specific examples of the divalent nitrogen-containing heterocyclic group include a pyridineyl group, a quinolinediyl group, and a pyrimidinediyl group, and a pyridinediyl group is particularly preferable.

  Z1 may have an arbitrary substituent at an arbitrary position. The number of substituents may be one, or two or more substituents may be used in any ratio and combination. Moreover, the kind of substituent is not restrict | limited, For example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, an amino group, a nitro group, a thiol group, a nitrile group etc. are mentioned. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, and an iodine atom. Examples of the halogenated alkyl group include a trifluoromethyl group.

  These substituents may be further substituted. Further, examples of the substituent that can be substituted include a substituent that can be substituted on Z1, among which a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group, a nitro group, and a trifluoromethyl group are preferable. And more preferably a hydrogen atom, a fluorine atom, a methyl group, or a methoxy group.

<Coupler residue Cp ₁ >
In the above formula (1), Cp ₁ represents an organic group having a hydroxyl group. Cp ₁ is optional as long as the effects of the present invention are not significantly impaired, but the carbon number is usually 1 or more, preferably 6 or more, more preferably 10 or more, and the upper limit is usually 50 or less, preferably 40. Hereinafter, it is desirable that the organic group is 35 or less. The carbon chain of Cp ₁ may be linear or may form a branched chain. Moreover, the ring may form and the number of the ring in the case of forming is arbitrary. Furthermore, a structure in which chain and cyclic groups are bonded may be used. Furthermore, it may have only a saturated bond or may have an unsaturated bond.

Cp ₁ may be substituted with a substituent. The number of substituents may be one or two or more. However, if the number of atoms in the substituent is too large, the electrical characteristics may be affected. Therefore, the number of atoms of the substituent is usually 40 or less, preferably 30 or less, more preferably 20 or less.

Examples of the substituent that can be substituted with Cp ₁ include an alkyl group, an alkoxy group, an aryl group, and an arylthio group.
Examples of the alkyl group include a methyl group, an ethyl group, and a propyl group.
Examples of the alkoxy group include a methoxy group, an ethoxy group, and a propoxy group.
Examples of the aryl group include a phenyl group and a naphthyl group.
Examples of the arylthio group include a phenylthio group.
The above substituents may be further substituted with, for example, an alkyl group such as a methyl group; a halogen atom such as a fluorine atom or a chlorine atom; a cyano group; a nitro group.

Among the above, Cp ₁ preferably has a structure represented by any one or more of the following formulas (3) to (6).
(In the formula (3) ~ (6), Z1 and ^{R 1,} .Z2 and Z3 represent the same as ^{R 1} in the formula (1) Z1 and the formula in (1A) each independently Represents an organic group having 30 or less carbon atoms having a ring structure, and Z4 represents an organic group having 30 or less carbon atoms having a ring structure and having at least one OH group, R ² , R ³ and R ⁴ are Each independently represents a halogen atom, a hydrogen atom, a nitrile group, or an optionally substituted group selected from the group consisting of an alkyl group, an aryl group and an alkoxy group, n ² is 0 or 1 Represents an integer.)

(Structure represented by the above formula (4))
The carbon number of Z2 is usually 3 or more, preferably 4 or more, and the upper limit is usually 30 or less, preferably 20 or less, more preferably 15 or less. Z2 has a ring structure bonded to the benzene skeleton of the above formula (4) at two or more locations, and among them, Z2 preferably has an aromatic ring as the ring structure.

Of the above preferred Z2, those represented by the following formula (7) or (8) are more preferred.

  Any of the organic groups represented by the formula (7) or (8) may have an arbitrary substituent at an arbitrary position. The number of substituents may be one, or two or more substituents may be used in any ratio and combination. Specific examples thereof include organic groups, amino groups, nitrile groups, thiol groups, nitro groups, and halogen atoms.

R ⁵ in the formula (8) is optional unless the effect of the present invention is significantly limited. For example, a hydrogen atom, a halogen atom, and an alkyl group, an alkoxy group which may have a substituent, An aryl group, a nitro group, etc. are mentioned. In this case, when R ⁵ is a group other than a hydrogen atom, R ⁵ is may be attached only one formula (8), it may be bonded to the plurality of R ^5. Specifically, the value of m representing the number of R ⁵ is desirably 4 or less. Incidentally, when a plurality of binding to each of R ⁵ may be the same or different.

The number of R ⁵ atoms is not particularly limited as long as the effect of the present invention is not significantly impaired, but is usually 1 or more, usually 25 or less, preferably 12 or less, more preferably 10 or less. When R ⁵ is a halogen atom, for example, a chlorine atom, a fluorine atom and the like are preferable.
When R ⁵ is an alkyl group, for example, a methyl group, an ethyl group, a propyl group and the like are preferable.
When R ⁵ is an alkoxy group, for example, a methoxy group, an ethoxy group, a propoxy group, and the like are preferable.
When R ⁵ is an aryl group, for example, a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group and the like are preferable.

  Moreover, these alkyl groups, alkoxy groups, and aryl groups may be substituted. The number of substituents may be one, or two or more substituents may be used in any ratio and combination. Examples of the substituent include an aryl group, an alkoxy group, an alkyl group, and a halogen atom.

In the formula (4), the bonding position of the functional group represented by the following formula (4A) may be substituted at any position of the phenylene ring to which the hydroxyl group is bonded or the ring of Z2. A preferred substitution position is the position represented by the following formula (9) (position adjacent to the hydroxyl group), and when Z2 has the structure of the above formula (7), for example, the following formula (10) Substitution positions are also preferred.

  A more preferred substitution position is the position represented by the above formula (9).

In formula (4), n ² represents an integer of 0 or 1. When n ² is 0, the nitrogen atom of the amide bond (—CONH—) specified in Formula (4) and R ² are directly bonded, and n ² is 0 from the viewpoint of electrical characteristics. Is preferred.

In formula (4), R ² is not limited as long as the effects of the present invention are not significantly impaired. Examples thereof include a hydrogen atom, a halogen atom, an alkyl group, an aryl group, and an alkoxy group. The carbon number of R ² is not limited, but is usually 1 or more, preferably 3 or more, and usually 10 or less, preferably 7 or less. Among these, an aryl group is preferable, and examples thereof include a phenyl group and a naphthyl group, and a phenyl group is more preferable.

This R ² may be substituted with a substituent. The number of substituents may be one, or two or more substituents may be used in any ratio and combination. Examples of the substituent include an alkyl group, an aryl group, an alkoxy group, a halogenated alkyl group, a halogen atom, etc. Among them, an alkoxy group, a halogenated alkyl group, a fluorine atom, and a chlorine atom are preferable, and a branched chain alkyl group is more preferable. Or the alkoxy group which has a cyclic alkyl group is preferable. The number of carbon atoms of the alkoxy group at this time is not limited, but is usually 3 or more, preferably 4 or more, and usually 11 or less, preferably 8 or less. Examples include isopropyloxy group, isobutyloxy group, isopentyloxy group, isohexyloxy group, 2-ethylbutyloxy group, 2-ethylhexyloxy group, cyclohexylmethyloxy group, and more preferably isobutyloxy. A cyclohexylmethyloxy group.

(Structure represented by the above formula (5))
Z3 has a carbon number of usually 1 or more, preferably 3 or more, more preferably 6 or more, and its upper limit is usually 30 or less, preferably 20 or less, more preferably from the viewpoint of improving electrical properties. It is desirable that it is 12 or less. Z3 has a ring structure bonded to the naphthalene skeleton of the above formula (4) at two or more positions. Among them, Z3 preferably has a hetero ring as the ring structure.

  Furthermore, it is also preferable to have one or more double bonds, preferably 2 or more, and usually 12 or less, preferably 8 or less, more preferably 6 or less. Furthermore, Z3 is preferably bonded to the naphthalene skeleton via a carbonyl group.

Among the above, as Z3, those represented by the following formulas (11) to (13) are more preferable.
In Formula (11) and Formula (12), Y1 represents a divalent aromatic hydrocarbon ring that may have a substituent, or a divalent nitrogen-containing heterocyclic ring that may have a substituent. Represent. Specific examples of the divalent aromatic hydrocarbon ring represented by Y1 include a benzene ring and a naphthalene ring, and a benzene ring is particularly preferable. Specific examples of the divalent nitrogen-containing heterocycle include a pyridine ring, a quinoline ring, and a pyrimidine ring, and a pyridine ring is particularly preferable.

Moreover, in Formula (11) and Formula (12), as described above, Y1 may have a substituent. The number of substituents may be one, or two or more substituents may be used in any ratio and combination. The type of the substituent is not limited, and examples thereof include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, an amino group, a nitro group, a thiol group, and a nitrile group.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group.
Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, and an iodine atom.
Examples of the halogenated alkyl group include a trifluoromethyl group.

  These substituents may be further substituted. Preferred are a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group, a nitro group and a trifluoromethyl group, and more preferred are a hydrogen atom, a methyl group and a methoxy group. In the case of further substitution, the number of substituents may be one, or two or more substituents may be used in any ratio and combination.

  Any of the compounds represented by formulas (11) to (13) may have an arbitrary substituent at an arbitrary position. The number of substituents may be one, or two or more substituents may be used in any ratio and combination. Moreover, the kind of substituent is not restrict | limited, For example, an organic group, an amino group, a nitrile group, a thiol group, a nitro group, a halogen atom etc. are mentioned.

R ⁶ in the formula (13) represents an alkyl group or an aryl group which may have a substituent. The number of carbon atoms of R ⁶ is not limited, but is usually 1 or more, preferably 6 or more, and usually 15 or less, preferably 10 or less. As the alkyl group, for example, methyl group, ethyl group, propyl group, butyl group and the like are preferable. As the aryl group, for example, a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group and the like are preferable.

  Moreover, these alkyl groups and aryl groups may be further substituted. Examples of the substituent include an alkyl group, an alkoxy group, a nitro group, and a halogen atom. The number of substituents may be one, or two or more substituents may be used in any ratio and combination.

(Structure represented by the above formula (6))
The number of carbon atoms of Z4 in the above formula (6) is usually 4 or more, preferably 5 or more, and usually 30 or less, preferably 15 or less, more preferably 10 or less. The number of hydroxyl groups is not limited, but is preferably 2 or less, particularly preferably 1. Z4 has a ring structure in which a 5-membered ring containing two nitrogen atoms in the formula (6) is bonded at two or more positions. However, Z4 preferably has a heterocyclic ring having a nitrogen atom and a double bond as a ring structure, and the number of the rings is usually 2 or less, preferably 1 or less.

Of the above preferred Z4, those represented by the following formula (14) are more preferred. In the following formula (14), the position at which the hydroxyl group is bonded is arbitrary.

  Any of the organic groups represented by the formula (14) may have an arbitrary substituent at an arbitrary position. The number of substituents may be one, or two or more substituents may be used in any ratio and combination. Specific examples include an organic group such as an alkyl group, an amino group, a nitrile group, a thiol group, a nitro group, and a halogen atom.

In addition, R ³ and R ⁴ in the formula (6) are not limited as long as the effects of the present invention are not significantly impaired. For example, they may have a halogen atom, a hydrogen atom, a nitrile group, or a substituent. An alkyl group, an aryl group, an alkoxy group, etc. are mentioned. At this time, at least one R ³ and R ⁴ may be bonded to each other in the formula (6). In addition, a plurality of R ³ and R ⁴ may be bonded to each other, but when a plurality of bonds are bonded, the same substituent may be bonded to each other, or different substituents may be bonded in any combination. Also good. The number of carbon atoms in R ³ and R ⁴ is not limited, but is usually 1 or more, usually 3 or less, preferably 2 or less.

<Substituent Rn>
Rn represents a substituent that substitutes for the naphthalene skeleton in formula (1). The number of atoms of Rn is usually 1 or more, preferably 2 or more, more preferably 5 or more, and the upper limit is usually 30 or less, preferably 25 or less, more preferably 20 or less. If the number of atoms is too large, the electrical characteristics may be affected. In addition, when Rn is substituted with the substituent mentioned later, it is preferable that the whole number of atoms including the number of atoms of a substituent satisfy | fill said range.

  The carbon number of Rn is usually 0 or more, preferably 1 or more, and the upper limit is usually 15 or less, preferably 10 or less, more preferably 8 or less. If the number of carbon atoms is too large, the electrical characteristics may be affected. In addition, when Rn is substituted with the substituent mentioned later, it is preferable that the whole carbon number including carbon number of a substituent satisfy | fill said range.

  The molecular weight of Rn is usually 15 or more, preferably 17 or more, more preferably 30 or more, and the upper limit is usually 250 or less, preferably 200 or less, more preferably 150 or less. If the molecular weight is too large, the electrical properties may be affected. In addition, when Rn is substituted with the substituent mentioned later, it is preferable that the whole molecular weight including the molecular weight of a substituent satisfy | fill said range.

The substituent Rn is optional as long as the effects of the present invention are not significantly impaired. Examples of the substituent Rn include an organic group containing a carbon atom and an organic group not containing a carbon atom. Examples of the organic group containing a carbon atom include hydrocarbon groups such as aliphatic hydrocarbon groups (for example, alkyl groups and alkenyl groups) and aromatic hydrocarbon groups (for example, aryl groups); alkoxy groups, aryloxy groups and the like An oxygen-containing hydrocarbon group; a halogenated hydrocarbon group containing a halogen atom such as a halogenated alkyl group or a halogenated aryl group; a primary to tertiary amino group substituted with a nitrile group or an organic group;
Moreover, as an inorganic group which does not contain a carbon atom, an unsubstituted amino group, a thiol group, a nitro group, a hydroxyl group, a halogen atom, etc. are mentioned, for example.

Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group.
Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, and an octyloxy group.
Examples of the alkenyl group include allyl group, methylallyl group, chloroallyl group and the like.
Examples of the aryl group include a phenyl group. Examples of the halogenated alkyl group include a trifluoromethyl group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, and an iodine atom.

  The above substituent Rn may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, and a halogen atom. The number of substituents may be one, or two or more substituents may be used in any ratio and combination.

Among the above substituents Rn, an alkyl group, an alkoxy group, a hydroxyl group, and a halogen atom are preferable, and an alkoxy group and a hydroxyl group are more preferable. Therefore, in the compound (1), the substituent Rn is preferably a functional group represented by the following formula (1A).
(In formula (1A), R ¹ represents a hydrogen atom or a hydrocarbon group which may have a substituent.)

(R ¹ )
In the above formula (1A), R ¹ represents a hydrogen atom or a hydrocarbon group which may have a substituent. Specific examples of the hydrocarbon group include aliphatic hydrocarbon groups such as alkyl groups, cycloalkyl groups, alkenyl groups, and aralkyl groups, and aromatic hydrocarbon groups such as aryl groups.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, and an n-octyl group.
Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like. These cyclo rings may be directly bonded to an oxygen atom, or may be bonded to an oxygen atom via a linking group such as an alkyl chain. Specific examples of the cyclo ring bonded to the oxygen atom through such an alkyl chain include, for example, a methylcyclohexyl group.
Examples of the alkenyl group include allyl group, methylallyl group, chloroallyl group and the like. Examples of the aralkyl group include a benzyl group and a phenylethyl group.
Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, an acenaphthyl group, a fluorenyl group, and an anthraquinolyl group.

When R ¹ is a hydrocarbon group, the carbon number of R ¹ is usually 1 or more, and the upper limit is usually 8 or less, preferably 6 or less, more preferably 5 or less. If the number of carbon atoms is too large, the electrical characteristics may be affected.

Among the above, R ¹ is preferably a hydrogen atom, an alkyl group, a cycloalkyl group, and an aralkyl group, and particularly preferably an alkyl group and a cycloalkyl group.

R ¹ may be substituted with any substituent. Specific examples of the substituent include an alkyl group, an alkoxy group, an aryl group, a halogen atom, a carbonyl group, and a carboxyl group. A substituent may be used individually by 1 type and may be used 2 or more types by arbitrary ratios and combinations.

Moreover, the substituent in which R ¹ is substituted may be further substituted with another substituent. Specific examples of the substituent in this case include a substituent that can be substituted on R ¹ . As the substituent for R ¹ , one type may be used alone, or two or more types may be used in any ratio and combination.

  When the compound (1) is used for a photoreceptor, there are advantages that the residual potential is low in terms of electrical characteristics and the adhesiveness is good in terms of strength.

<Preferable bonding position of hydroxyl group in Cp ₁ and naphthalene skeleton in formula (1)>
An atom bonded to a nitrogen atom constituting an azo bond in the naphthalene skeleton in the above formula (1) (that is, the structural portion shown in the following formula (15), hereinafter referred to as “coupler residue (15)”). Is optional as long as the effect of the present invention is not significantly impaired, but is preferably adjacent to the atom substituted with a hydroxyl group or adjacent to the adjacent carbon atom.

In Cp ₁ as well, an atom bonded to the nitrogen atom constituting the azo bond is arbitrary as long as the effect of the present invention is not significantly impaired. However, for example, when Cp ₁ has a structure represented by any of the above formulas (3) to (6), the atom bonded to the nitrogen atom constituting the azo bond is adjacent to the atom substituted with a hydroxyl group. Or the next adjacent carbon atom is preferable.

When a specific example of these positional relationships is expressed by a formula, a structure described in the following formula (16) group is obtained. However, the atom bonded to the nitrogen atom constituting the azo bond is preferably the adjacent carbon atom adjacent to the atom substituted by the hydroxyl group, or the adjacent adjacent carbon atom, and the structure described in the group of the formula (16) It is not limited to. In Cp ₁ or the coupler residue (15), when hydrogen is not bonded to the adjacent carbon atom adjacent to the hydroxyl group or adjacent to the adjacent carbon atom, an azo bond is formed with the carbon atom. Usually, it is not bonded to the nitrogen atom. In addition, the structure described in the following formula (16) group is an excerpt of Cp ¹ or the coupler residue (15) and a part of the nitrogen atom constituting the azo bond in the formula (1).

[1-2. Specific example of preferred compound (1)]
The compound (1) can have any structure as long as it has the above structure. Among them, the compound (1) is, Cp _1, the following structural formula (A), and a coupler residue (15) preferably has either a combination according to Tables 1 to 9 below.

In addition, the atom in Cp ₁ and the coupler residue (15) that is bonded to the nitrogen atom constituting the azo bond is the carbon atom adjacent to the atom substituted by the hydroxyl group or the adjacent adjacent carbon atom. However, it is not limited to the examples in Table 1 to Table 9.
In addition, Cp ₁ and the coupler residue (15) are usually a mixture of two or more as described in the reaction formula (a) described later, but the following table describes some structures in the mixture. did.

[1-3. Method for producing compound (1)]
As long as said compound (1) is obtained, the manufacturing method of compound (1) can be manufactured by arbitrary methods. Especially, it is preferable to manufacture a compound (1) according to the following method. Hereinafter, although an example of the manufacturing method of a compound (1) is described, the manufacturing method of a compound (1) is not limited to the following content, It can manufacture by arbitrary methods.

A coupler corresponding to Cp ₁ in the formula (1) and a coupler having a structure represented by the formula (15) (hereinafter referred to as “coupler (15)” as appropriate) are represented by the formula (11). Similarly to the compound having a structure and the compound having a structure represented by the formula (12), it can be obtained by a known method. For example, the coupler (15) is prepared by combining a hydroxy naphthalic anhydride derivative and a diamine with an organic solvent such as acetic acid or nitrobenzene as shown in the following reaction formula (a) described in JP-B 61-30263. It can be obtained by heating in and dehydrating condensation.

  The coupler (15) obtained by the above synthesis method is obtained as a mixture of two isomers. In the present invention, any isomer can be used, and the mixture is used without separating the isomers. A coupling reaction can be performed.

  Further, when Rn is a hydroxyl group in the above formula (15), the coupler (15) can be further induced to react with an alkyl halide under basic conditions such as potassium carbonate and sodium hydroxide to induce an alkoxy group. Is possible. However, it may be difficult to selectively convert only one hydroxyl group of the coupler (15) having two hydroxyl groups into an alkoxy group from the viewpoints of purity, yield and the like. However, this can be solved, for example, by using a protecting group. Various protecting groups can be used. For example, after introducing only one protecting group using a bulky protecting group under basic conditions using potassium carbonate, sodium hydroxide, etc., the same conditions are used. To convert to an alkoxy group. Then, by removing the protective group (that is, deprotection), the coupler (15) in which the target Rn is an alkoxy group can be obtained with high purity and high yield. Specific examples of the protecting group include a methanesulfonyl group and a p-toluenesulfonyl group. From the viewpoint of high selectivity, a p-toluenesulfonyl group is preferable. When deprotection is performed, for example, an alcohol such as methanol, ethanol, propanol or the like is used as a reaction solvent, and the reaction solution is brought to a basic condition with an aqueous potassium hydroxide solution, an aqueous sodium hydroxide solution, or the like at room temperature (normally 25 ° C ) To the reflux temperature of the solvent, the desired alkoxy-substituted coupler (15) can be obtained.

Compound (1) can be synthesized by various known methods such as the method described in JP-A No. 63-195657. Among these, a method for producing compound (1) by coupling reaction of a tetrazonium salt represented by the formula (b) with a coupler corresponding to Cp ₁ and a coupler (15) is more convenient.

(In the formula ^(b), n ^1, Ar 1, Ar ² and X represents the same as ^{n 1,} Ar 1, Ar ² and X in the formula (1). In addition, ^{W 1} is an anion functional Represents a group.)

  As a reaction solvent for the coupling reaction, solvents such as water, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, methanol, ethanol, propanol, etc. are usually used, preferably water. N, N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone are used. The liquid property during the coupling reaction is arbitrary as long as the effects of the present invention are not significantly impaired. Usually, the coupling reaction is carried out under weakly alkaline conditions. Examples of the basic substance used to make the liquid property weakly alkaline include sodium acetate, potassium acetate and the like, and sodium acetate is particularly preferable. A reaction solvent may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

  The temperature during the coupling reaction is usually 5 ° C or higher, preferably 10 ° C or higher, more preferably 15 ° C or higher, and the upper limit is usually 35 ° C or lower, preferably 30 ° C or lower, more preferably 25 ° C or lower. It is desirable to do in. When the reaction temperature is too high, the decomposition of the tetrazonium salt occurs, and when it is too low, the progress of the coupling reaction is slow, and the reaction may not be completed.

  The reaction time is usually 30 minutes or longer, preferably 1 hour or longer, and its upper limit is usually 10 hours or shorter, preferably 5 hours or shorter.

[2. Electrophotographic photoreceptor]
The photoconductor of the present invention is a photoconductor used in an image forming apparatus for forming an electrostatic latent image by exposing the photoconductor with monochromatic light having a wavelength of 380 nm or more and 500 nm or less, and comprising a photosensitive layer containing the compound (1). It is what you have.

  The photoreceptor usually has a photosensitive layer on a conductive support. As the photosensitive layer structure constituting the photoreceptor, any known structure can be used, but specific examples of the structure include a layer containing a charge generating substance and a layer containing a charge transporting substance. Examples thereof include a laminated type photosensitive member and a single layer type photosensitive member in which a charge generating material is dispersed in a layer containing a charge transporting material.

  Further, in the laminated type photoreceptor, there are a forward laminated type photoreceptor in which the charge generation layer and the charge transport layer are laminated in this order from the support side, and a reverse laminated type photoreceptor in which they are laminated in reverse order. Although a structure can also be used, a sequentially laminated type photoreceptor capable of exhibiting balanced photoconductivity is particularly preferable.

  In either case, compound (1) is contained in the photosensitive layer that the photoreceptor normally has. The compound (1) is usually used as a charge generating substance in the photosensitive layer, but its function is not particularly limited. Further, other compounds may be used in combination. Usually, the charge generation material exhibits the same function as a function of generating charge regardless of whether it is used for a single layer type photoreceptor or a laminated type photoreceptor.

  The compound (1) is partially described in JP-A-2-11069, JP-A-9-50139, etc., but it is excellent when the exposure light is monochromatic light having a wavelength of 380 nm to 500 nm. It is not known to have the same properties.

  When the exposure light wavelength is monochromatic light of 380 nm to 500 nm, in order to form a good image, the transmittance of the exposure light wavelength in the charge transport layer is preferably 87% or more, more preferably 90%. Above, more preferably 93% or more, particularly preferably 95% or more. (The charge transport layer will be described later.) When a photosensitive layer including such a charge transport layer is selected, conventionally, the adhesive strength of the photosensitive layer may be inferior, and the film of the photosensitive member may be damaged and cannot be put into practical use. There was a thing. However, the photosensitive layer containing the compound (1) has an excellent effect that the adhesive strength of the photosensitive layer is good in addition to the excellent effect in terms of electrical characteristics. The reason for this is not necessarily clear, but when the compound (1) is used as a charge generation material, the entanglement with the charge generation layer binder, the charge transport agent, the charge transport layer binder, etc. is increased and the adhesive strength is improved. Presumed to be.

  In the photoreceptor of the present invention, the compound (1) is usually contained as a charge generating substance. However, in addition to the compound (1), other charge generation materials may be contained. At this time, other charge generation materials may be used alone, or two or more may be used in any ratio and combination.

  The amount of the other charge generating material to be used is not limited, but in order to obtain the effect of the present invention sufficiently, the weight of the other charge generating material to be used contained in the photosensitive layer exceeds the weight of the compound (1). Preferably not.

  When a charge generation material is used in addition to the compound (1), for example, an inorganic photoconductive material and an organic photoconductive material can be used as the charge generation material. Examples of the inorganic photoconductive material include selenium and its alloys, cadmium sulfide and the like. Examples of organic photoconductive materials include phthalocyanine pigments, azo pigments, dithioketopyrrolopyrrole pigments, squalene pigments, quinacridone pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, anthanthrone pigments, benzimidazole pigments, Examples include thioindigo pigments, anthraquinone pigments, cyanine pigments, pyrylium pigments, and thiopyrylium pigments. Of these, organic pigments, particularly phthalocyanine pigments and azo pigments are preferred.

  Specific examples of phthalocyanine pigments include metal-free phthalocyanine, copper, indium, gallium, tin, titanium, zinc, vanadium, silicon, germanium, and other metals, or oxides, halides, hydroxides, alkoxides, and the like. Examples include various crystal forms of coordinated phthalocyanines.

  Among the most sensitive crystal types are X-type, τ-type metal-free phthalocyanine, A-type (also known as β-type), B-type (also known as α-type), D-type (also known as Y-type), etc. Indium phthalocyanine, chlorogallium phthalocyanine such as type II, hydroxygallium phthalocyanine such as type V, μ-oxo-gallium phthalocyanine dimer such as type G and type I, μ-oxo-aluminum phthalocyanine dimer such as type II, etc. Is preferred. Further, among these phthalocyanines, A-type, B-type, D-type titanyl phthalocyanine, II-type chlorogallium phthalocyanine, V-type hydroxygallium phthalocyanine, G-type μ-oxo-gallium phthalocyanine dimer and the like are particularly preferable.

  In particular, oxytitanium phthalocyanine preferably has a clear diffraction peak mainly at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray.

  Further, oxytitanium phthalocyanine preferably has a clear diffraction peak at a Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.7 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray.

  Specific examples of the azo pigment include bisazo pigments, trisazo pigments, tetrakis pigments, and the like. Specific examples of suitable azo compounds are described below.

[2-1. Structure of photoconductor]
The photoconductor of the present invention is an electrophotographic photoconductor that is exposed to monochromatic light having a wavelength of 380 nm or more and 500 nm or less to form an electrostatic latent image, and has a photosensitive layer containing the above compound (1). As long as other configurations are not particularly limited. However, in general, the photoreceptor of the present invention is provided with a photosensitive layer containing the above-described compound of the present invention on a conductive support. Hereinafter, the photoconductor of the present invention will be described in more detail on the assumption that the photoconductor of the present invention has such a configuration. However, the photoconductor of the present invention is limited to the contents described below as long as it has the above-described configuration. Is not to be done.

[2-1-1. Conductive support]
The conductive support is not particularly limited, and for example, metal materials such as aluminum, aluminum alloy, stainless steel, copper, and nickel; conductive powders such as metal, carbon, and tin oxide are included to impart conductivity. Resin materials; resin, glass, paper, etc., which are formed by depositing or coating a conductive material such as aluminum, nickel, ITO (indium tin oxide alloy) on the surface, etc. are mainly used, but do not significantly limit the effects of the present invention. As long as it is not limited to this. Among them, the material for the conductive support is preferably a material having a specific resistance of 10 ³ Ωcm or less at normal temperature (usually 25 ° C.). Moreover, a conductive support body may be used individually by 1 type, or may use 2 or more types together by arbitrary ratios and combinations. Examples of the shape of the conductive support include a drum shape, a sheet shape, and a belt shape. In addition, as a conductive support, a conductive support having an appropriate resistance value may be used on a conductive support made of an arbitrary metal material for controlling conductivity and surface properties and / or for covering defects. The thing which apply | coated the property material may be used.

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

The anodized film is formed, for example, by anodizing in an acidic solution. Specific examples of the acidic solution used at this time include chromic acid, sulfuric acid, oxalic acid, boric acid, sulfamic acid, and the like. Among them, sulfuric acid is preferable. When anodizing is performed using sulfuric acid, the concentration of sulfuric acid is usually 100 g / L or more, and the upper limit is preferably 300 g / L or less. The dissolved aluminum concentration is usually 2 g / L or more, and the upper limit is usually 15 g / L or less. Furthermore, the reaction temperature is usually 15 ° C. or higher, and the upper limit is preferably 30 ° C. or lower. Furthermore, the electric field voltage is usually 10 V or higher, and the upper limit is preferably 20 V or lower. At this time, the current density is usually 0.5 A / dm ² or more, and the upper limit is preferably ^{2 A} / dm ² or less. In addition, an acidic solution may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

  The average film thickness of the anodized film is usually 3 μm or more, preferably 5 μm or more, and usually 20 μm or less, preferably 7 μm or less. When the average film thickness of the anodic oxide coating is thick, it must be processed under strong conditions such as high concentration of the sealing agent, high processing temperature, and long processing time in the sealing processing described later. There is a case. Accordingly, there is a possibility that the productivity of the photosensitive member is deteriorated and surface defects such as spots, dirt, and dusting are likely to occur on the coating surface.

  It is preferable to perform a sealing treatment on the formed anodized film. The sealing treatment can be carried out by any known method, for example, a low-temperature sealing treatment immersed in an aqueous solution containing nickel fluoride as a main component, or an aqueous solution containing, for example, nickel acetate as a main component. It is preferably applied by high-temperature sealing treatment or the like soaked in the substrate.

  The concentration of the nickel fluoride aqueous solution used when the above-mentioned low temperature sealing treatment is performed can be any concentration, but is usually 3 g / L or more, and the upper limit is usually 6 g / L or less. Therefore, it is desirable to use at a concentration in this range. The treatment temperature is usually 25 ° C. or higher, preferably 30 ° C. or higher, and usually 40 ° C. or lower, preferably 35 ° C. or lower. Further, it is desirable that the nickel fluoride aqueous solution is treated in a range of usually pH 4.5 or higher, preferably pH 5.5 or higher, and usually pH 6.5 or lower, preferably pH 6.0 or lower. At this time, any known pH adjusting agent can be used as the pH adjusting agent. Specifically, oxalic acid, boric acid, formic acid, acetic acid, sodium hydroxide, sodium acetate, aqueous ammonia, etc. are used. Is preferred. The reason is to allow the low temperature sealing process to proceed smoothly. In addition, a pH adjuster may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations. The treatment time is usually 1 minute or more per 1 μm of film thickness, and the upper limit is usually 3 minutes or less, and treatment is preferably performed within this range. In order to further improve the physical properties of the film, cobalt fluoride, cobalt acetate, nickel sulfate, a surfactant and the like may be contained in the nickel fluoride aqueous solution. After the low-temperature sealing treatment, usually washing and drying are performed.

  Moreover, when performing said high temperature sealing process, it is preferable to use nickel acetate, cobalt acetate, lead acetate, nickel acetate-cobalt, barium nitrate, etc. as a sealing agent, and it is especially preferable to use nickel acetate. When nickel acetate aqueous solution is used as the sealing agent, the concentration of the solution can be any concentration, but is usually 5 g / L or more, and the upper limit is usually 20 g / L or less, It is desirable to use it at a concentration. The treatment temperature is usually 80 ° C or higher, preferably 90 ° C or higher, and usually 100 ° C or lower, preferably 98 ° C. The pH of the aqueous nickel acetate solution is usually 4.0 or higher, preferably 5.0 or higher, and usually 8.0 or lower, preferably 6.0 or lower. At this time, any known pH adjusting agent can be used as the pH adjusting agent, but it is preferable to use ammonia water, sodium acetate, or the like. The reason is to allow the high temperature sealing process to proceed smoothly. In addition, a pH adjuster may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations. The time for the high-temperature sealing treatment is usually 10 minutes or longer, preferably 20 minutes or longer, and usually 100 minutes or shorter, preferably 60 minutes or shorter. In order to further improve the physical properties of the film, sodium acetate, an organic carboxylic acid, an anionic surfactant, a nonionic surfactant or the like may be contained in the nickel acetate aqueous solution. After the high temperature treatment, it is preferable to further carry out treatment with high temperature water not containing salts, high temperature steam or the like. And after a high temperature sealing process, it usually wash | cleans and dries.

  The surface of the conductive support may be smooth, or may be roughened by using an arbitrary cutting method or polishing. Moreover, you may roughen by mixing the particle | grains of a suitable particle size with the material which comprises a support body. In order to reduce the cost, it is possible to use the drawing tube as it is without cutting. Especially when using a non-cutting aluminum support such as drawing, impact processing, ironing, etc., the above treatment eliminates dirt, foreign matter, and other small scratches on the surface, resulting in a uniform and clean support. Since it is obtained, it is preferable.

  The surface roughness Ra of the conductive support is preferably 0.01 μm or more, preferably 0.3 μm or less, and more preferably 0.20 μm or less. If the surface roughness Ra is too small, adhesion of the photosensitive layer or the like to the conductive support may be deteriorated, and if the surface roughness Ra is too large, image defects such as black spots may easily occur. .

As a method for processing the surface roughness of the conductive support within the above range, for example, a method of cutting and roughening the surface of the conductive support with a cutting tool or the like; collision of fine particles with the surface of the conductive support Sand blasting method by performing; Processing method by ice particle cleaning device described in JP-A-4-204538; Honing method described in JP-A-9-236937; Anodizing method; Anodizing method; Buffing method; method by laser ablation described in JP-A-4-233546; method using polishing tape described in JP-A-8-001502; roller burnishing processing described in JP-A-8-001510 Methods and the like. However, the method for roughening the surface of the conductive support is not limited thereto.
(Definition and measurement method of surface roughness)

  The surface roughness Ra means arithmetic average roughness and represents an average value of absolute value deviations from the average line. Specifically, a reference length is extracted from the roughness curve in the direction of the average line, and the absolute values of deviations from the average line of the extracted portion to the measurement curve are summed and averaged.

  The surface roughness Ra can be measured by, for example, a surface roughness meter (Tokyo Seimitsu Surfcom 570A). However, other measuring instruments may be used as long as the measuring instrument produces the same result within the error range.

[2-1-2. Undercoat layer]
An undercoat layer may be provided between the conductive support and the photosensitive layer in order to improve adhesiveness, blocking property and the like. As the undercoat layer, for example, a resin, a resin in which particles such as a metal oxide are dispersed, or the like is used. In particular, the undercoat layer is preferably obtained by dispersing metal oxide particles in a binder resin.
The undercoat layer may be a single layer or a plurality of layers. Further, the thickness of the undercoat layer can be arbitrarily selected, but it is usually preferably 0.1 μm or more, and the upper limit thereof is usually 20 μm or less in view of the photoreceptor characteristics and applicability. The undercoat layer may contain, for example, an antioxidant. In addition, an undercoat layer may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

  Hereinafter, the undercoat layer will be described in more detail by using as an example the undercoat layer obtained by dispersing metal oxide particles in a binder resin. However, the content described below is an example of the undercoat layer, and the undercoat layer is not limited to the one described below.

(Metal oxide particles)
As the metal oxide particles contained in the undercoat layer, metal oxide particles that can be used for a photoreceptor can be used unless the effects of the present invention are significantly limited. Specific examples thereof include metal oxide particles containing one metal element such as titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, zinc oxide, iron oxide, calcium titanate, strontium titanate, barium titanate. In particular, metal oxide particles containing a plurality of metal elements, such as metal oxide particles including a metal oxide having a band gap of usually 2 eV or more and an upper limit of 4 eV or less are preferable. If the band gap is too small, carrier injection from the conductive support is likely to occur, and defects such as black spots and color spots are likely to occur when an image is formed. If the band gap is too large, electron trapping occurs. Charge transfer may be hindered and electrical characteristics may deteriorate.

  Among these metal oxide particles, titanium oxide, aluminum oxide, silicon oxide and zinc oxide are preferable, titanium oxide and aluminum oxide are more preferable, and titanium oxide is particularly preferable.

  In addition, as for these metal oxide particles, one type of particles may be used alone, or a plurality of types of particles may be mixed and used in an arbitrary ratio and combination. Further, the metal oxide particles may be formed from only one kind of metal oxide, or may be formed by using two or more kinds of metal oxides in combination at an arbitrary ratio and combination.

(Crystal form of metal oxide particles)
The crystal form of the metal oxide particles is arbitrary as long as the effects of the present invention are not significantly impaired. For example, there is no restriction | limiting in the crystal type of the metal oxide particle (namely, titanium oxide particle) which used the titanium oxide as a metal oxide, For example, all, such as a rutile, anatase, brookite, an amorphous, can be used. Further, the crystal form of the titanium oxide particles may include those having a plurality of crystal states from those having different crystal states.

(Surface treatment of metal oxide particles)
Further, the surface of the metal oxide particles may be subjected to various surface treatments. For example, treatment with a treating agent such as 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 organic silicon compound may be performed. One of these treatment agents may be used alone, or two or more thereof may be used in any ratio and combination.

  In particular, when titanium oxide particles are used as the metal oxide particles, the surface treatment is preferably performed with an organosilicon compound. Examples of the organosilicon compound include silicone oils such as dimethylpolysiloxane and methylhydrogenpolysiloxane; organosilanes such as methyldimethoxysilane and diphenyldimethoxysilane; silazanes such as hexamethyldisilazane; vinyltrimethoxysilane and γ-mercaptopropyl. Examples thereof include silane coupling agents such as trimethoxysilane and γ-aminopropyltriethoxysilane.

The metal oxide particles are particularly preferably treated with a silane treatment agent represented by the structure of the following formula (17) (hereinafter referred to as “silane treatment agent (17)” as appropriate). The silane treatment agent (17) is a good treatment agent with good reactivity with the metal oxide particles.

In the above formula (17), R ^u1 and R ^u2 each independently represent an alkyl group. The number of carbon atoms of R ^u1 and R ^u2 is not limited, but is usually 1 or more, and the upper limit is usually 18 or less, preferably 10 or less, more preferably 6 or less, and particularly 3 or less. When the carbon number is within the range, the reactivity between the silane treating agent (17) and the metal oxide particles becomes suitable. When the number of carbon atoms is too large, the reactivity with the metal oxide particles may be reduced, or the dispersion stability of the treated metal oxide particles in the coating solution may be reduced.
Preferable specific examples of R ^u1 and R ^u2 include methyl group, ethyl group, propyl group and the like.

In the above formula (17), R ^u3 represents an alkyl group or an alkoxy group. Although there is no restriction ^| limiting in carbon number of ^Ru3 , Usually, it is 1 or more, and the upper limit is 18 or less normally, Preferably it is 10 or less, More preferably, it is 6 or less, Most preferably, it is 3 or less. When the carbon number is within the range, the reactivity between the silane treating agent (17) and the metal oxide particles becomes suitable. When the number of carbon atoms is too large, the reactivity with the metal oxide particles may be reduced, or the dispersion stability of the treated metal oxide particles in the coating solution may be reduced.
Specific examples of suitable R ^u3 include a methyl group, an ethyl group, a methoxy group, and an ethoxy group.

  In addition, when processing with the above processing agents, the outermost surface is normally processed with a silane processing agent (17). At this time, the surface treatment may be performed by only one surface treatment, or two or more surface treatments may be performed in any combination. For example, before the surface treatment with the silane treating agent (17), it may be treated with a treating agent such as aluminum oxide, silicon oxide or zirconium oxide. Moreover, you may use together the metal oxide particle to which different surface treatment was given by arbitrary ratios and combinations.

(Volume average particle diameter of metal oxide particles)
The volume average particle diameter of the metal oxide particles is usually 20 nm or more, and the upper limit thereof is usually 0.1 μm or less, preferably 95 nm or less, more preferably 90 nm or less. When the volume average particle diameter is in this range, the exposure-charging repetition characteristics under low temperature and low humidity are stable, and image defects such as black spots and color spots can be suppressed from occurring in the obtained image.
The volume average particle diameter of the metal oxide particles is measured dynamically with respect to a liquid in which metal oxide particles are dispersed in a liquid in which methanol and 1-propanol are mixed in a weight ratio of 7: 3. Measured by light scattering method. The dynamic light scattering method will be described later.

(Cumulative 90% particle diameter accumulated from the small particle size side of the metal oxide particles)
The cumulative 90% particle size accumulated from the small particle size side of the metal oxide particles is usually 0.05 μm or more, and the upper limit is usually 0.3 μm or less, preferably 0.2 μm or less, more preferably 0.15 μm. It is as follows. If the cumulative 90% particle size is too small, the coating solution for forming the undercoat layer described later may be coated and dried to form a subbing layer, which may reduce the storage stability of the coating solution and is too large. Then, image defects such as black spots and color spots may occur.

  In conventional electrophotographic photoreceptors, the undercoat layer may contain metal oxide particles that are large enough to penetrate the front and back of the undercoat layer, and the large metal oxide particles may cause defects during image formation. There was sex. Further, when a contact type is used as the charging means, when the photosensitive layer is charged, the charge moves from the conductive substrate to the photosensitive layer through the metal oxide particles so that the charging is appropriately performed. There was also a possibility that could not be. However, when the cumulative 90% particle diameter accumulated from the small particle diameter side of the metal oxide particles is within the above range, the large metal oxide particles are very few. Therefore, the electrophotographic photosensitive member according to the present invention can suppress the occurrence of defects and the inability to appropriately charge, and enables high-quality image formation.

(Evaluation of particle size distribution of metal oxide particles by dynamic scattering method)
The metal oxide particles in the undercoat layer are preferably present as primary particles. However, there are few such cases in general, and there are many cases where they are aggregated and exist as aggregate secondary particles, or both are mixed. Therefore, it is preferable to evaluate the state of the metal oxide particles by measuring the particle size distribution of the metal oxide particles in the undercoat layer. Although it is very difficult to directly evaluate the particle size distribution of the metal oxide particles in the undercoat layer, by dispersing the undercoat layer in a specific solvent and evaluating the dispersion, The particle size distribution of the metal oxide particles can be evaluated.

  Specifically, for example, the volume average particle diameter and the small particle diameter side of the metal oxide particles in a liquid in which the undercoat layer is dispersed in a solvent in which methanol and 1-propanol are mixed at a weight ratio of 7: 3. As the accumulated 90% particle diameter, a value measured by the dynamic light scattering method can be used regardless of the form of the metal oxide particles.

In the dynamic light scattering method, the speed of Brownian motion of finely dispersed particles is detected, and the particle size distribution is detected by irradiating the particles with laser light and detecting light scattering (Doppler shift) with different phases according to the speed. Is what you want. The value of the volume average particle diameter of the metal oxide particles in the undercoat layer is a value when the metal oxide particles are stably dispersed in a solvent in which methanol and 1-propanol are mixed at a weight ratio of 7: 3. It does not mean the particle size of metal oxide particles or the like as powder before dispersion.
In actual measurement, it is preferable to use a dynamic light scattering type particle size analyzer (manufactured by Nikkiso Co., Ltd., MICROTRAC UPA model: 9340-UPA, hereinafter referred to as “UPA” as appropriate) with the following settings. The specific measurement operation is preferably performed based on the instruction manual for the particle size analyzer (manufactured by Nikkiso Co., Ltd., Document No. T15-490A00, revised No. E).
・ Setting of dynamic light scattering particle size analyzer
Measurement upper limit: 5.9978 μm
Measurement lower limit: 0.0035 μm
Number of channels: 44
Measurement time: 300 seconds
Measurement temperature: 25 ° C
Particle permeability: Absorption
Particle refractive index: N / A (not applicable)
Particle shape: Non-spherical
Density: 4.20 (g / cm ³ ) (The density value is for titanium dioxide particles. In the case of other particles, it is preferable to use the values described in the above instruction manual.)
Dispersion medium type: Mixed solvent of methanol and 1-propanol (weight ratio: methanol / 1-propanol = 7/3)
Dispersion medium refractive index: 1.35

  If the solution in which the undercoat layer is dispersed in a solvent in which methanol and 1-propanol are mixed at a weight ratio of 7: 3 is too concentrated and the concentration is outside the measurable range of the measuring device The coating solution for forming the undercoat layer described later is diluted with a mixed solvent of methanol and 1-propanol (methanol / 1-propanol = 7/3 (weight ratio); refractive index: 1.35), and the concentration is measured by a measuring device. Is preferably within a measurable range. For example, in the case of the above-mentioned UPA, it is preferable to dilute with a mixed solvent of methanol and 1-propanol so that the sample concentration index (SIGNAL LEVEL) suitable for measurement is usually 0.6 or more.

  Even if the dilution is performed in this way, the particle diameter of the metal oxide particles in the solution in which the undercoat layer is dispersed is considered not to change, so the volume average particle diameter measured as a result of the above dilution, The cumulative 90% particle diameter is treated as a volume average particle diameter measured in a liquid in which the undercoat layer is dispersed in a solvent in which methanol and 1-propanol are mixed at a weight ratio of 7: 3, and a cumulative 90% particle diameter. Shall.

(Average primary particle diameter of metal oxide particles)
There is no restriction | limiting in the average primary particle diameter of a metal oxide particle, and it is arbitrary unless the effect of this invention is impaired remarkably. However, the average primary particle diameter of the metal oxide particles is determined by the arithmetic average value of the particle diameters directly observed by a transmission electron microscope (hereinafter referred to as “TEM” as appropriate). Is usually 1 nm or more, preferably 5 nm or more, and usually 100 nm or less, preferably 70 nm or less, more preferably 50 nm or less.

(Refractive index of metal oxide particles)
There is no restriction | limiting in the refractive index of a metal oxide particle, What kind of thing can be used if it can be used for a photoreceptor. The refractive index of the metal oxide particles is usually 1.3 or more, preferably 1.4 or more, more preferably 1.5 or more, and usually 3.0 or less, preferably 2.9 or less, more preferably 2. 8 or less.

(Binder resin)
As the binder resin contained in the undercoat layer, any resin can be used as long as the effects of the present invention are not significantly impaired. Usually, a binder resin that can be used for a photoreceptor can be used. Usually, it is soluble in a solvent such as an organic solvent, and the undercoat layer after formation is insoluble or soluble in a solvent such as an organic solvent used in a coating solution for forming a photosensitive layer. Use the one with low. In addition, binder resin may be used individually by 1 type and may be used 2 or more types by arbitrary ratios and combinations.

  Examples of the binder resin used in the undercoat layer include phenoxy resin, epoxy resin, polyethylene resin, polypropylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, and 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 resins, cellulose esters such as nitrocellulose and celluloses such as cellulose ether resins, casein, gelatin, polyglutamic acid, starch, starch acetate Organic starch compounds such as amino starch, zirconium chelate compounds, zirconium alkoxide compounds, organic titanyl compounds such as titanyl chelate compounds and titanyl alkoxide compounds, silane coupling agents, etc. Polyamide resins such as polyamide are preferred because they exhibit good dispersibility and coatability. However, the present invention is not limited to these unless the effects of the present invention are significantly limited.

  As the polyamide resin, for example, so-called copolymer nylon obtained by copolymerizing 6-nylon, 66-nylon, 610-nylon, 11-nylon, 12-nylon, etc .; N-alkoxymethyl-modified nylon, N-alkoxyethyl-modified Examples thereof include alcohol-soluble nylon resins such as a type obtained by chemically modifying nylon such as nylon.

Among these polyamide resins, a copolymerized polyamide resin containing a diamine component corresponding to the diamine represented by the following formula (18) (hereinafter appropriately referred to as “diamine component (18)”) as a constituent component is particularly preferable.

In the above formula ^{(18), R} u4 ~R ^u7 each independently represent a hydrogen atom or an organic substituent. a and b each independently represent an integer of usually 0 or more and 4 or less. In addition, when there exist two or more said organic substituents, those substituents may mutually be the same and may differ.

Examples of suitable ones as organic substituent represented by R ^u4 to R ^u7, like hydrocarbon group which may contain a hetero atom. Among these, preferred examples include alkyl groups such as methyl group, ethyl group, n-propyl group, and isopropyl group; alkoxy groups such as methoxy group, ethoxy group, n-propoxy group, and isopropoxy group; phenyl group, naphthyl group, Examples include an aryl group such as an anthryl group and a pyrenyl group, and an alkyl group or an alkoxy group is more preferable. Particularly preferred are a methyl group and an ethyl group.

Although the carbon number of the organic substituent represented by R ^u4 to R ^u7 is optional unless significantly impairing the effects of the present invention, usually 1 or more and usually 20 or less, preferably 18 or less, more preferably 12 or less. When there are too many carbon atoms, the solubility with respect to a solvent will deteriorate, a coating liquid may gelatinize, or even if it melt | dissolves temporarily, a coating liquid may become cloudy or gelatinize with progress of time.

  The copolymerized polyamide resin containing the diamine component (18) as a constituent component may contain a constituent component other than the diamine component (18) (hereinafter simply referred to as “other polyamide constituent component”) as a constituent unit. . Examples of other polyamide constituents include lactams such as γ-butyrolactam, ε-caprolactam, lauryllactam; 1,4-butanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,20-eicosanedicarboxylic acid, and the like. Dicarboxylic acids; diamines such as 1,4-butanediamine, 1,6-hexamethylenediamine, 1,8-octamethylenediamine, 1,12-dodecanediamine; piperazine and the like. At this time, examples of the copolymerized polyamide resin include those obtained by copolymerizing the constituent components into binary, ternary, quaternary, and the like. Other polyamide components may be used alone or in combination of two or more in any ratio and combination.

  When the copolymerized polyamide resin containing the diamine component (18) as a constituent component contains other polyamide constituent components as constituent units, the proportion of the diamine component (18) in the total constituent components is not limited, but usually 5 mol % Or more, preferably 10 mol% or more, more preferably 15 mol% or more, and usually 40 mol% or less, preferably 30 mol% or less. If the amount of the diamine component (18) is too small, the change in electrical characteristics under high-temperature and high-humidity conditions may increase, and the stability of the electrical characteristics against environmental changes may be deteriorated. May be worse.

Specific examples of the copolymerized polyamide resin are shown below. However, in the following specific examples, the copolymerization ratio represents the monomer charge ratio (molar ratio).

  There is no restriction | limiting in particular in the manufacturing method of said copolyamide, The normal polycondensation method of polyamide is applied suitably. For example, a polycondensation method such as a melt polymerization method, a solution polymerization method, and an interfacial polymerization method can be appropriately applied. In the polymerization, for example, a monobasic acid such as acetic acid or benzoic acid; a monoacid base such as hexylamine or aniline or the like may be included in the polymerization system as a molecular weight regulator. Moreover, you may use it with the shape hardened with the hardening | curing agent. Among these, alcohol-soluble copolymerized polyamide, modified polyamide, and the like are preferable because they exhibit good dispersibility and coating properties.

(Number average molecular weight of binder resin)
There is no limitation on the number average molecular weight of the binder resin. For example, when a copolymerized polyamide is used as the binder resin, the number average molecular weight of the copolymerized polyamide is usually 10,000 or more, preferably 15000 or more, and usually 50000 or less, preferably 35000 or less. Even if the number average molecular weight is too small or too large, it may be difficult to maintain the uniformity of the undercoat layer.

(Use ratio of metal oxide particles and binder resin)
The use ratio of the metal oxide particles and the binder resin is arbitrary as long as the effects of the present invention are not significantly impaired. However, the metal oxide particles are usually 0.5 parts by weight or more, preferably 0.7 parts by weight or more, more preferably 1.0 parts by weight or more, and usually 4 parts by weight with respect to 1 part by weight of the binder resin. Hereinafter, it is preferably used in the range of 3.8 parts by weight or less, more preferably 3.5 parts by weight or less. If the metal oxide particles are too small relative to the binder resin, the electrical characteristics of the photoreceptor may be deteriorated, and in particular, the residual potential may be increased. Moreover, when there are too many metal oxide particles with respect to binder resin, there exists a possibility that image defects, such as a black spot of a picture formed using the said photoreceptor and a color point, may increase.

(Additive)
The undercoat layer may contain an additive. The kind of additive is arbitrary as long as the effects of the present invention are not significantly impaired. Moreover, an additive may be used individually by 1 type and may use 2 or more types by arbitrary ratios and combinations.

(Coating solution for undercoat layer formation)
The undercoat layer is usually obtained by applying a coating solution for forming the undercoat layer. Various physical properties of the undercoat layer usually depend on the physical properties of the coating solution for forming the undercoat layer.

  The content of the binder resin in the coating solution is arbitrary as long as the effects of the present invention are not significantly impaired. However, the content of the binder resin in the coating solution for forming the undercoat layer is usually 0.5% by weight or more, preferably 1% by weight or more, and usually 20% by weight or less, preferably 10% by weight or less. Use in a range.

Usually, the coating liquid for forming the undercoat layer is obtained by dissolving or dispersing the components constituting the undercoat layer in a solvent.
As the solvent (solvent for the undercoat layer) used in the coating solution for forming the undercoat layer, any solvent can be used as long as it can dissolve the binder resin. As this solvent, an organic solvent is usually used. Examples of the solvent include alcohols having 5 or less carbon atoms such as methanol, ethanol, 1-propanol or 2-propanol; chloroform, 1,2-dichloroethane, dichloromethane, trichrene, carbon tetrachloride, 1,2-dichloropropane. Halogenated hydrocarbons such as: Nitrogen-containing organic solvents such as dimethylformamide; Aromatic hydrocarbons such as toluene and xylene.

  Moreover, the said solvent may be used individually by 1 type, and may use 2 or more types together by arbitrary ratios and combinations. Furthermore, even if the solvent does not dissolve the binder resin alone, it can be used as long as the binder resin can be dissolved by using a mixed solvent with another solvent (for example, the organic solvent exemplified above). . Usually, by using a mixed solvent, coating unevenness can be reduced.

  In the coating liquid for forming the undercoat layer, the weight ratio between the solvent and the solid content of the metal oxide particles, the binder resin, and the like varies depending on the application method of the coating liquid for forming the undercoat layer. What is necessary is just to change suitably and use so that a uniform coating film may be formed in the apply | coating method.

  The coating liquid for forming the undercoat layer may contain components other than the metal oxide particles, the binder resin, and the solvent described above as long as the effects of the present invention are not significantly impaired. For example, the coating liquid for forming the undercoat layer may contain additives as other components. Examples of the additive include sodium phosphite, sodium hypophosphite, phosphorous acid, hypophosphorous acid, heat stabilizers typified by hindered phenol, and other polymerization additives. In addition, an additive may be used individually by 1 type and may use 2 or more types together by arbitrary ratios and combinations.

  There is no restriction | limiting in particular in the manufacturing method of a coating liquid. However, the coating liquid for forming the undercoat layer contains metal oxide particles as described above, and the metal oxide particles are dispersed in the coating liquid for forming the undercoat layer. To do. Therefore, the manufacturing method of the coating liquid for forming the undercoat layer usually has a dispersion step of dispersing the metal oxide particles.

[2-1-3. Photosensitive layer]
The photosensitive layer is formed on the conductive support (when the undercoat layer is provided, on the undercoat layer). As the structure of the photosensitive layer, any known structure can be used. As an example of a specific configuration, a laminated structure comprising two or more layers including a charge generation layer in which a charge generation material is dispersed in a binder resin and a charge transport layer in which a charge transport material is dispersed in a binder resin And a single layer type photosensitive layer having a single phase structure in which a charge transport material and a charge generation material are both dispersed in a binder resin. In addition, in the laminated type photosensitive layer, there are a normal laminated type photoreceptor in which the charge generation layer and the charge transport layer are laminated in this order from the conductive support side, and a reverse laminated type photoreceptor in which the reverse order is laminated.

  Usually, the charge generation material exhibits an equivalent function as a function of generating charge regardless of whether it is used for a single layer type photoreceptor or a laminated type photoreceptor. Therefore, the photoconductor of the present invention can be applied to any configuration of the photoconductive layer, but a sequentially laminated photoconductor capable of exhibiting balanced photoconductivity is particularly preferable.

(Charge generating material)
As the charge generation material, it is preferable to use at least one compound (1) as described above. Moreover, you may use 2 or more types of compounds (1) by arbitrary ratios and combinations. Furthermore, as long as the effects of the present invention are not significantly disturbed, known charge generating substances can be used in any ratio and combination.

(Laminated photosensitive layer)
When the photoreceptor of the present invention is a multilayer photoreceptor, the layer containing a charge generating substance is usually a charge generating layer. However, in the multilayer photoconductor, a charge generating material may be contained in the charge transport layer as long as the effects of the present invention are not significantly impaired.

-Charge generation layer:
The charge generation layer in the multilayer photosensitive layer usually contains a charge generation material. The charge generation layer may be formed on a vapor deposition film or the like using the above charge generation material alone, but is usually used in a form in which the charge generation material is bound with a binder resin. In particular, when an organic pigment is used as the charge generation material, it is preferable to use the organic pigment fine particles bound in a binder resin. Such a charge generation layer is prepared by, for example, preparing a coating solution by dissolving or dispersing a charge generation material and a binder resin in a solvent or a dispersion medium. (In the case of providing an undercoat layer, on the undercoat layer), and in the case of a reverse lamination type photosensitive layer, it can be obtained by coating and drying on a charge transport layer.

  There is no limitation on the binder resin used for the charge generation layer in the multilayer photosensitive layer, for example, polyvinyl acetal such as polyvinyl butyral resin, polyvinyl formal resin, and partially acetalized polyvinyl butyral resin in which part of butyral is modified with formal, acetal, or the like. 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, cellulose resin, polyurethane resin, epoxy resin, silicone resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, casein, Vinyl chloride-vinyl acetate such as vinyl chloride-vinyl acetate copolymer, hydroxy-modified vinyl chloride-vinyl acetate copolymer, carboxyl-modified vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, etc. Copolymer, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, styrene-alkyd resin, silicone-alkyd resin, insulating resin such as phenol-formaldehyde resin, poly-N-vinylcarbazole, polyvinylanthracene, Mention may be made of organic photoconductive polymers such as polyvinylperylene. Also, for example, polyvinyl acetate, polyacrylic acid ester, polymethacrylic acid ester, polyvinyl acetoacetal, polyvinyl propional, cellulose ester, cellulose ether, butadiene, styrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, vinyl Examples thereof include polymers and copolymers of vinyl compounds such as alcohol and ethyl vinyl ether, polyamides, silicon resins, and the like, but are not limited thereto as long as the effects of the present invention are not significantly impaired. These may be used individually by 1 type and may use 2 or more types together by arbitrary ratios and combinations.

  Moreover, there is no restriction | limiting in the solvent and dispersion medium which melt | dissolve binder resin and are used for preparation of a coating liquid, Arbitrary solvents and dispersion media can be used. Specific examples thereof include cyclic saturated aliphatic, aromatic, halogenated aromatic, amide, alcohol, aliphatic polyhydric alcohol, chain and cyclic ketone, ester, halogenated hydrocarbon, chain and cyclic. Examples include ethers, aprotic polar substances, nitrogen-containing compounds, mineral oils such as ligroin, water, and the like, but are not limited to these unless the effects of the present invention are significantly impaired. In addition, a solvent and / or a dispersion medium may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

  Examples of the cyclic saturated aliphatic solvent or dispersion medium include pentane, hexane, octane, nonane, methylcyclohexane, ethylcyclohexane, and the like. Examples of the aromatic solvent or dispersion medium include toluene, xylene, anisole, and the like. Examples of the halogenated aromatic solvent or dispersion medium include chlorobenzene, dichlorobenzene, chloronaphthalene, and the like. Examples of the amide solvent or dispersion medium include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and the like. Examples of the alcohol solvent or dispersion medium include methanol, ethanol, isopropanol, n-butanol, and benzyl alcohol. Examples of the solvent or dispersion medium for aliphatic polyhydric alcohols include ethylene glycol, glycerin, polyethylene glycol, and the like. Examples of the solvent or dispersion medium for the chain and cyclic ketones include acetone, cyclohexanone, methyl ethyl ketone, and the like. Examples of the ester solvent or dispersion medium include methyl formate, ethyl acetate, and n-butyl acetate. Examples of the halogenated hydrocarbon solvent or dispersion medium include methylene chloride, chloroform, 1,2-dichloroethane, and the like. Examples of the chain or cyclic ether solvent or dispersion medium include diethyl ether, dimethoxyethane, tetrahydrofuran, 1,4-dioxane, methyl cellosolve, ethyl cellosolve, and ethylene glycol monomethyl ether. Examples of the aprotic polar solvent or dispersion medium include acetonitrile, N, N-dimethylformamide, 1,3-dimethyl-2-imidazolinone, N-methyl-2-pyrrolidone, γ-butyrolactone, dimethyl sulfoxide, sulfolane. , Hexamethylphosphoric triamide, and the like. Examples of the nitrogen-containing compound solvent or dispersion medium include n-butylamine, isopropanolamine, diethylamine, triethanolamine, ethylenediamine, triethylenediamine, and triethylamine.

  Among the above solvents or dispersion media, those that do not dissolve the undercoat layer are preferred. Moreover, these may be used individually by 1 type and may use 2 or more types together by arbitrary ratios and combinations. In addition, said substance is an illustration and is not limited to these, unless the effect of this invention is impaired remarkably.

  The content ratio (weight ratio) of the binder resin and the charge generation material in the charge generation layer of the multilayer photosensitive layer is usually 30 parts by weight or more, preferably 50 parts by weight of the charge generation material with respect to 100 parts by weight of the binder resin. In addition, the range is usually 500 parts by weight or less, preferably 300 parts by weight or less. If the ratio of the charge generation material is too low, the sensitivity of the photoreceptor may be lowered. If it is too high, the stability of the coating solution may be reduced due to aggregation of the charge generation material. When a plurality of types of charge generating materials are used in combination, it is preferable that the total of these charge generating materials be within the above range.

  The thickness of the charge generation layer of the multilayer photosensitive layer is arbitrary, but is usually 0.1 μm or more, preferably 0.15 μm or more, and usually 2 μm or less, preferably 0.8 μm or less. In both cases where the film thickness is too thin and too thick, the electrical characteristics may be adversely affected.

  When dissolving or dispersing the charge generation material in a solvent or dispersion medium, paint charge shaker grinding, sand grind mill, ball mill, ultrasonic treatment, stirring, ball mill dispersion method, attritor dispersion method, sand mill A well-known refinement method such as a dispersion method, a planetary mill dispersion method, a roll mill dispersion method, or an ultrasonic dispersion method can be arbitrarily used. At the time of dispersion, it is preferable that the volume average particle diameter of the charge generation material is reduced to a particle size of usually 1 μm or less, preferably 0.5 μm or less.

  The volume average particle diameter of the charge generating material can also be measured in the same manner as when measuring the volume average diameter of the metal oxide particles contained in the undercoat layer in the photoreceptor of the present invention. The volume average particle diameter can also be measured, for example, by a known particle size analyzer using a laser diffraction scattering method, a particle size analyzer using a light transmission centrifugal sedimentation method, or the like.

-Charge transport layer:
The charge transport layer in the multilayer photosensitive layer may be a single layer as long as it is a layer containing a charge transport material, or a stack of layers having different constituent components or different constituent ratios of constituent components. It may be. In particular, the charge transport layer in the laminated photosensitive layer is preferably used in a form in which a charge transport material is bound with a binder resin. Such a charge transport layer is prepared by, for example, dissolving or dispersing a charge transport material and a binder resin in a solvent or a dispersion medium to prepare a coating solution. In the case of an inversely laminated photosensitive layer, it can be obtained by applying and drying in the form of a conductive support (on the undercoat layer when an undercoat layer is provided).

  As long as the charge transporting substance is a substance that transports charges, any known compound can be used in any ratio and combination as long as the effect of the present invention is not significantly impaired.

  However, since the forward laminated type photosensitive layer functions when the light passing through the charge transport layer or the photosensitive layer reaches the charge generation material, these layers have excellent exposure light transmission properties that do not block the exposure light. It is preferable. Therefore, it is preferable that the charge transport material and the binder resin have high compatibility and do not cause the constituent materials to precipitate or turbidity.

  Further, in the case of the charge transport layer of the sequential lamination type photosensitive layer, in order to form a good image, the transmittance of the exposure light wavelength in the charge transport layer is preferably 87% or more, more preferably 90% or more, and further preferably. Is preferably 93% or more, particularly preferably 95% or more.

  In particular, it is desirable that the transmittance of the exposure light in the charge transport layer is in the above range when the exposure light is monochromatic light having a wavelength of 380 nm to 500 nm.

  The exposure light transmittance of the charge transport layer can be achieved, for example, by using the compound of the present invention as a charge generation material and appropriately selecting the charge transport material. Also, the transmittance can be made desired by adjusting the film thickness of the charge transport layer.

  Any known method can be used to measure the transmittance of exposure light. For example, the layer is formed on a transparent plate (for example, a quartz glass plate) at a measurement wavelength, and is commercially available. It can measure with a spectrophotometer.

  Specific examples of such charge transport materials include diphenoquinone derivatives, aromatic nitro compounds such as 2,4,7-trinitrofluorenone, carbazole derivatives, indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, oxadi Heterocyclic compounds such as azole derivatives, pyrazoline derivatives, thiodiazole derivatives, nitrogen-containing compounds such as aniline derivatives, hydrazone compounds, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine compounds, or a combination of these compounds, or Examples thereof include polymers having a group consisting of these compounds in the main chain or side chain. In addition, a charge transport substance may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

Among these, specific examples of preferable charge transport materials include compounds having the following skeletons. In these skeletons, an alkyl group, an alkoxy group, an aryl group, or the like may be substituted as a substituent.

  In the above formula, A represents a linking group. A is optional as long as the effects of the present invention are not significantly impaired, but it is desirable that the alkylidene has a carbon number of usually 10 or less, preferably 8 or less, more preferably 6 or less.

Among these, a compound having the following structure is particularly preferable because it has a good effect when used in combination with the charge generation layer containing the compound of the present invention.

Furthermore, a compound represented by the following formula (19) is particularly preferable from the viewpoint of the electrical characteristics of the photoreceptor.

In formula (19), R ⁷ and R ⁸ each independently represent a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, or the like. R ⁹ and R ¹⁰ each independently represents an alkylene group which may have a substituent, or an arylene group which may have a substituent. R ¹¹ , R ¹² , R ¹³ and R ¹⁴ each independently represents an alkyl group which may have a substituent or an aryl group which may have a substituent. However, at least one of R ^{11 to} R ¹⁴ is preferably an aryl group having a substituent. In addition, said substituent may have one and may have two or more. When it has two or more, each may be the same substituent or different substituents. Moreover, when it is a different substituent, it can be used in arbitrary ratios and combinations.

In formula (19), R ⁷ is preferably a group having a chiral center, and more preferably the chiral center is a carbon atom. The group bonded to the chiral center of R ⁷ is not particularly limited as long as it is not a group that deteriorates electrical properties such as a carbonyl group, an alkoxycarbonyl group, and a nitro group. The group bonded to the chiral center of R ⁷ is a hydrogen atom, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, an alkynyl group which may have a substituent, And an aryl group which may have a substituent is preferred. Among these, a hydrogen atom, an alkyl group which may have a substituent, and an alkenyl group which may have a substituent are more preferable. Furthermore, a hydrogen atom or an alkyl group which may have a substituent is particularly preferable. The alkyl group represented by R ⁷ has usually 1 or more, preferably 2 or more, particularly preferably 3 or more, and usually 20 or less, preferably 15 or less, particularly preferably 10 or less.

Examples of the substituent that the alkyl group, alkenyl group, alkynyl group, and aryl group may have as R ⁷ are a hydroxyl group, a methyl group that may be further substituted, an ethyl group, and a propyl group. And an aryl group such as an optionally substituted phenyl group and an aryl group such as a naphthyl group, and an optionally substituted arylthio group such as a phenylthio group. Examples of the group that further substitutes the above substituent include an alkyl group such as a methyl group and a halogen atom such as a fluorine atom.

Examples of R ⁷ which is a group having at least one chiral center, for example, include a group represented by the following formula (20).

In the formula (20), R ¹⁵ , R ¹⁶ and R ¹⁷ are different from each other, and are a hydrogen atom, an optionally substituted alkyl group, or an optionally substituted alkenyl group. Represents. Among these, two of R ^{15 to} R ¹⁷ are alkyl groups which may have a substituent, and one in which one is a hydrogen atom is particularly preferable.

Examples of the substituent that the alkyl group or alkenyl group may have as the above R ^{15 to} R ¹⁷ include a hydroxyl group, and an alkyl group such as a methyl group, an ethyl group, and a propyl group, which may be further substituted. Further, an aryl group such as a phenyl group which may be further substituted and a naphthyl group, an arylthio group such as a phenylthio group which may be further substituted, and the like may be mentioned.

  Examples of the group that further substitutes the above substituent include an alkyl group such as a methyl group and a halogen atom such as a fluorine atom.

In Formula (19), R ⁸ represents a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, or the like. Among these, R ⁸ is preferably a hydrogen atom or an alkyl group which may have a substituent, and particularly preferably a hydrogen atom.

Further, examples of the substituent group which may have an alkyl group and an aryl group, described above, for example, such substituents listed in the above R ¹⁵ to R ¹⁷ can be mentioned.

In formula (19), R ⁹ and R ¹⁰ each independently represents an alkylene group which may have a substituent, or an arylene group which may have a substituent. Among them, R ⁹ and R ¹⁰ are each independently preferably an arylene group which may have a substituent, more preferably a phenylene group, and a 1,4-phenylene group. Particularly preferred.

Further, examples of the substituent group which may have an alkylene group and arylene group, of the above, for example, such substituents exemplified in the description of the R ¹⁵ to R ¹⁷ can be mentioned.

In formula (19), R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ each independently represents an alkyl group that may have a substituent, or an aryl group that may have a substituent. Represent. However, at least one group of R ^{11 to} R ¹⁴ is an aryl group having a substituent. That is, the other three groups may be an alkyl group which may have a substituent or an aryl group which may have a substituent. Especially, it is preferable that two or more groups are the aryl groups which may have a substituent among R < ¹¹ > -R < ¹⁴ >. Furthermore, it is particularly preferable that all groups are aryl groups which may have a substituent.

Specific examples of the aryl group include a phenyl group and a naphthyl group. Examples of the substituent include those similar to the substituents that can be substituted with R ^{15 to} R ^17. Among them, an alkyl group is preferable, and the 3-position and / or the carbon atom bonded to the nitrogen atom is preferable. Alternatively, a tolyl group and a xylyl group having a substituted methyl group at the 4-position are particularly preferable.

Examples of charge transport materials suitable for the present invention are given below.

  Examples of the binder resin used in the charge transport layer of the laminated photoreceptor and the photosensitive layer of the single-layer photoreceptor include vinyl polymers such as polymethyl methacrylate, polystyrene, and polyvinyl chloride, and copolymers and polycarbonates thereof. , Polyester, polyester carbonate, polysulfone, polyimide, phenoxy resin, epoxy resin, silicone resin, and the like, and these partially crosslinked cured products or a mixture thereof can be used, but the effect of the present invention is not significantly limited. As long as it is not limited to this. Binder resin may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

  Among these, preferred binder resins include polycarbonate resins and polyester resins. Polycarbonate resins and polyester resins usually have a partial structure of a diol component. Examples of the diol component that forms these structures include bisphenol residues and biphenol residues.

  Specific examples of the compound having a bisphenol residue as a diol component include bis- (4-hydroxy-3,5-dimethylphenyl) methane, bis- (4-hydroxyphenyl) methane, and bis- (4-hydroxy-3- Methylphenyl) methane, 1,1-bis- (4-hydroxyphenyl) ethane, 1,1-bis- (4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxyphenyl) propane, 2,2 -Bis- (4-hydroxy-3-methylphenyl) propane, 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis- (4-hydroxyphenyl) pentane, 2,2-bis- ( 4-hydroxyphenyl) -3-methylbutane, 2,2-bis- (4-hydroxyphenyl) hexane, 2,2-bis- (4-hydroxyphenyl) ) -4-methylpentane, 1,1-bis- (4-hydroxyphenyl) cyclopentane, 1,1-bis- (4-hydroxyphenyl) cyclohexane, bis- (3-phenyl-4-hydroxyphenyl) methane, 1,1-bis- (3-phenyl-4-hydroxyphenyl) ethane, 1,1-bis- (3-phenyl-4-hydroxyphenyl) propane, 2,2-bis- (3-phenyl-4-hydroxy) Phenyl) propane, 1,1-bis- (4-hydroxy-3-methylphenyl) ethane, 2,2-bis- (4-hydroxy-3-methylphenyl) propane, 2,2-bis- (4-hydroxy) -3-ethylphenyl) propane, 2,2-bis- (4-hydroxy-3-isopropylphenyl) propane, 2,2-bis- (4-hydroxy-) -Sec-butylphenyl) propane, 1,1-bis- (4-hydroxy-3,5-dimethylphenyl) ethane, 2,2-bis- (4-hydroxy-3,5-dimethylphenyl) propane, 1, 1-bis (4-hydroxy-3,5-dimethylphenyl) cyclohexane, 1,1-bis- (4-hydroxy-3,6-dimethylphenyl) ethane, bis- (4-hydroxy-2,3,5- Trimethylphenyl) methane, 1,1-bis- (4-hydroxy-2,3,5-trimethylphenyl) ethane, 2,2-bis- (4-hydroxy-2,3,5-trimethylphenyl) propane, bis -(4-hydroxy-2,3,5-trimethylphenyl) phenylmethane, 1,1-bis- (4-hydroxy-2,3,5-trimethylphenyl) phenylethane 1,1-bis- (4-hydroxy-2,3,5-trimethylphenyl) cyclohexane, bis- (4-hydroxyphenyl) phenylmethane, 1,1-bis- (4-hydroxyphenyl) -1- Phenylethane, 1,1-bis- (4-hydroxyphenyl) -1-phenylpropane, bis- (4-hydroxyphenyl) diphenylmethane, bis- (4-hydroxyphenyl) dibenzylmethane, 4,4 ′-[1 , 4-phenylenebis (1-methylethylidene)] bis- [phenol], 4,4 ′-[1,4-phenylenebismethylene] bis- [phenol], 4,4 ′-[1,4-phenylenebis (1-Methylethylidene)] bis- [2,6-dimethylphenol], 4,4 ′-[1,4-phenylenebismethylene] bis- [2,6-di Tylphenol], 4,4 ′-[1,4-phenylenebismethylene] bis- [2,3,6-trimethylphenol], 4,4 ′-[1,4-phenylenebis (1-methylethylidene)] Bis- [2,3,6-trimethylphenol], 4,4 ′-[1,3-phenylenebis (1-methylethylidene)] bis- [2,3,6-trimethylphenol], 4,4′- Dihydroxydiphenyl ether, 4,4-bis (4-hydroxyphenyl) valeric acid stearyl ester, 4,4′-dihydroxydiphenylsulfone, 4,4′-dihydroxydiphenyl sulfide, 3,3 ′, 5,5′-tetramethyl- 4,4′-dihydroxydiphenyl ether, 3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxydiphenylsulfone, 3,3 , 5,5′-tetramethyl-4,4′-dihydroxydiphenyl sulfide, phenolphthalein, 4,4 ′-[1,4-phenylenebis (1-methylvinylidene)] bisphenol, 4,4 ′-[1 , 4-phenylenebis (1-methylvinylidene)] bis [2-methylphenol], (2-hydroxyphenyl) (4-hydroxyphenyl) methane, (2-hydroxy-5-methylphenyl) (4-hydroxy-3 -Methylphenyl) methane, 1,1- (2-hydroxyphenyl) (4-hydroxyphenyl) ethane, 2,2- (2-hydroxyphenyl) (4-hydroxyphenyl) propane, 1,1- (2-hydroxy) Phenyl) (4-hydroxyphenyl) propane, and the like.

  Specific examples of the compound having a biphenol residue as a diol component include 4,4′-biphenol, 2,4′-biphenol, 3,3′-dimethyl-4,4′-dihydroxy-1,1′-. Biphenyl, 3,3′-dimethyl-2,4′-dihydroxy-1,1′-biphenyl, 3,3′-di- (t-butyl) -4,4′-dihydroxy-1,1′-biphenyl, 3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxy-1,1′-biphenyl, 3,3 ′, 5,5′-tetra- (t-butyl) -4,4′- And dihydroxy-1,1′-biphenyl, 2,2 ′, 3,3 ′, 5,5′-hexamethyl-4,4′-dihydroxy-1,1′-biphenyl, and the like.

  Among these, preferred compounds are bis- (4-hydroxy-3,5-dimethylphenyl) methane, bis- (4-hydroxyphenyl) methane, bis- (4-hydroxy-3-methylphenyl) methane, 2, 2-bis- (4-hydroxy-3-methylphenyl) propane, 1,1-bis- (4-hydroxyphenyl) ethane, 2,2-bis- (4-hydroxyphenyl) propane, 2-hydroxyphenyl (4 -Hydroxyphenyl) methane, 2,2- (2-hydroxyphenyl) (4-hydroxyphenyl) propane and other compounds having bisphenol residues as components.

Specific examples of preferred diol components (for example, bisphenol and biphenol) of the polycarbonate resin are shown below, but are not limited thereto.

In particular, in order to maximize the effects of the present invention, a diol component having the following structure is preferable.

Moreover, it is preferable to use polyarylate for improving mechanical properties. In this case, it is preferable to use a compound having the following structure as the diol component.

Furthermore, although polycarbonate resin and polyester resin contain an acid component, it is preferable to use the compound of the following structures as this acid component.

Furthermore, among these, an acid component having the following structure is particularly preferable.

  In addition, a diol component and an acid component may be used individually by 1 type, and may use 2 or more types by arbitrary ratios and combinations.

  If the molecular weight of the binder resin in the charge transport layer of the laminated photosensitive layer is too small, the mechanical strength may be insufficient. Conversely, if the molecular weight is too large, the viscosity of the coating solution for forming the photosensitive layer is too high. Productivity may be reduced. Therefore, for example, when a polycarbonate resin and / or a polyarylate resin is used as the binder resin, the viscosity average molecular weight is usually 10,000 or more, preferably 20,000 or more, and usually 100,000 or less, more preferably 70000 or less. About the calculation method of a viscosity average molecular weight, it can measure by the method as described in an Example using an Ubbelohde type capillary viscometer etc., for example.

  The content ratio (weight ratio) between the binder resin and the charge transport material in the charge transport layer of the multilayer photosensitive layer is usually 30 parts by weight or more, preferably 40 parts by weight or more with respect to 100 parts by weight of the binder resin. The amount is usually 200 parts by weight or less, preferably 150 parts by weight or less. If the ratio of the charge transport material is too high, the mechanical strength of the charge transport layer may be lowered. On the other hand, if the ratio of the charge transport material is too low, the electrical characteristics may be deteriorated. When a plurality of types of charge generation materials are used in combination, it is preferable that the total of these charge generation materials be within the above range.

  The thickness of the charge transport layer of the multilayer photosensitive layer is usually 5 μm or more, preferably 8 μm or more, and usually 45 μm or less, preferably 35 μm or less. If the film thickness is too thin, the life of the photoreceptor may be shortened due to wear, and if the film thickness is too thick, the resolution of the image may deteriorate due to exposure light, charge diffusion, or the like. That is, by adjusting the film thickness of the charge transport layer to an appropriate thickness, the degree of exposure light reaching the charge generation material can also be adjusted.

(Single layer type photosensitive layer)
The single-layer type photosensitive layer is a layer having the same configuration as the charge transport layer of the above-mentioned multilayer type photoreceptor, and it is preferable that the above-mentioned charge generating substance is dispersed. Specifically, the single-layer type photosensitive layer is obtained by dissolving or dissolving the above-described charge generating substance, charge transporting substance, and binder resin used for the charge transporting layer in the laminated type photosensitive layer in a solvent or dispersion medium. It can be obtained by dispersing and preparing a coating solution, and applying and drying on a conductive support (if an undercoat layer is provided, on the undercoat layer).

  The types of the charge transport material and the binder resin and the use ratio (weight ratio) thereof are preferably in the same range as described for the charge transport layer of the laminated photosensitive layer. Usually, a charge generating substance is further dispersed in the layer containing these charge transporting substance and binder resin.

  As the charge generation material, the same materials as those described for the charge generation layer of the laminated photosensitive layer can be used. However, in the case of a single-layer type photosensitive layer, it is preferable to make the particle size of the charge generating material sufficiently small. Specifically, the particle size of the charge generation material is usually 1 μm or less, preferably 0.5 μm or less. The particle diameter can be measured by, for example, a microtrack particle size distribution measuring apparatus using a laser diffraction / scattering method. If the amount of the charge generating material dispersed in the single-layer type photosensitive layer is too small, sufficient sensitivity may not be obtained, and if it is too large, chargeability and sensitivity may be lowered. Accordingly, the amount of the charge generating material to be dispersed is usually 0.5% by weight or more, preferably 1% by weight or more, and usually 50% by weight or less, preferably 20% by weight, based on the entire monolayer type photosensitive layer. Used in the following ranges.

  The thickness of the photosensitive layer of the single-layer type photoreceptor is arbitrary as long as the effects of the present invention are not significantly impaired, but are usually 5 μm or more, preferably 10 μm or more, and usually 50 μm or less, preferably 45 μm or less. If the film thickness is too thin, the life of the photoreceptor may be shortened due to wear, and if the film thickness is too thick, the resolution of the image may deteriorate due to exposure light, charge diffusion, or the like.

  The content ratio (weight ratio) between the binder resin and the charge generating material in the single-layer type photosensitive layer is usually 1 part by weight or more, preferably 2 parts by weight or more, based on 100 parts by weight of the binder resin. The amount is 10 parts by weight or less, preferably 8 parts by weight or less.

  Since the single-layer type photosensitive layer functions when the light passing through the photosensitive layer reaches the charge generation material, it is preferable that these layers have excellent exposure light transmittance so as not to block exposure light. . Therefore, it is preferable that the charge transport material and the binder resin have high compatibility and do not cause the constituent materials to precipitate or turbidity.

  In the case of a single-layer type photosensitive layer, in order to form a good image, the transmittance of the photosensitive layer at the wavelength of exposure light is preferably 87% or more, more preferably 90% or more, still more preferably 93% or more. In particular, it is desirable that it is 95% or more.

  In particular, the transmittance of the exposure light in the photosensitive layer when the exposure light is monochromatic light having a wavelength of 380 nm to 500 nm is preferably in the above range.

  The transmittance of the exposure light of the photosensitive layer can be achieved by appropriately selecting the charge transport material, for example, using a compound represented by a preferred specific example of the charge transport material as a charge transport material. Further, the transmittance can be made desired by adjusting the film thickness of the photosensitive layer.

  Any known method can be used for measuring the transmittance of exposure light. For example, the layer is formed on a transparent plate (for example, a quartz glass plate) at a measurement wavelength, and is commercially available. It can be measured with a spectrophotometer.

(Additive)
The laminated type photosensitive layer and the single layer type photosensitive layer are intended to improve, for example, film forming property, flexibility, coating property, stain resistance, gas resistance, light resistance, etc. in the photosensitive layer or each layer constituting the photosensitive layer. Thus, for example, additives such as known plasticizers, antioxidants, ultraviolet absorbers, electron-withdrawing compounds, leveling agents, and surfactants may be contained.

Examples of additives used in the charge transport layer include known plasticizers, crosslinking agents, antioxidants, stabilizers, sensitizers used to improve film formability, flexibility, and mechanical strength. Various additives such as various leveling agents for improving coating properties, dispersion aids, and the like.
Examples of the plasticizer include aromatic compounds such as phthalic acid esters, phosphoric acid esters, epoxy compounds, chlorinated paraffins, chlorinated fatty acid esters, and methylnaphthalene.
Examples of the antioxidant include hindered phenol compounds and hindered amine compounds.
Examples of the leveling agent include silicone oil and fluorine oil.
An additive may be used individually by 1 type and may use 2 or more types together by arbitrary ratios and combinations.

(Surface layer)
In addition to the laminated photosensitive layer and the single-layer photosensitive layer, the photosensitive layer formed by the above procedure may be the uppermost layer, that is, the surface layer, but another layer may be provided thereon to form the surface layer. .

  For example, a protective layer may be provided for the purpose of preventing or reducing mechanical deterioration such as wear of the photosensitive layer and electrical deterioration of the photosensitive layer due to discharge products generated from a charger or the like. The protective layer can be formed by any known method. For example, the protective layer may be formed by containing a conductive material in an appropriate binder resin, or charge transport such as a triphenylamine skeleton described in JP-A-9-190004. A copolymer using a compound having a function can be used.

  Examples of the conductive material that can be used for the protective layer include aromatic amino compounds such as TPD (N, N′-diphenyl-N, N′-bis- (m-tolyl) benzidine), antimony oxide, indium oxide, Metal oxides such as tin oxide, titanium oxide, tin oxide-antimony oxide, aluminum oxide, and zinc oxide can be used, but are not limited thereto. In addition, a conductive material may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

  As the binder resin used for the protective layer, for example, a known resin such as polyamide resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinyl ketone resin, polystyrene resin, polyacrylamide resin, or siloxane resin may be used. In addition, 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 can also be used. In addition, binder resin may also be used individually by 1 type, and may use 2 or more types by arbitrary ratios and combinations.

The electrical resistance of the protective layer is usually 10 ⁹ Ω · cm or more, and the upper limit is preferably 10 ¹⁴ Ω · cm or less. If the electric resistance is higher than the above range, the residual potential may be increased, resulting in an image with much fogging. If the electric resistance is lower than the above range, the image may be blurred or the resolution may be reduced. Further, the protective layer must be configured so as not to prevent transmission of light irradiated during image exposure.

  In addition, for the purpose of reducing the frictional resistance of the surface of the photoconductor, reducing the wear, and increasing the transfer efficiency of the toner from the photoconductor to the transfer belt, paper, etc., the surface layer is made of a fluorine resin, silicone resin, polyethylene resin, or the like You may make the surface layer contain the particle | grains which consist of these resin, and / or the particle | grains of an inorganic compound. Alternatively, a layer containing these resins and particles may be newly formed as a surface layer.

(Method for forming each layer)
The photosensitive layer in the photoreceptor of the present invention is usually formed by repeating a coating / drying step for each layer sequentially with a coating solution obtained by dissolving or dispersing the substance to be contained in a solvent or dispersion medium. The The kind of the solvent or dispersion medium used in this case is not limited, and one type may be used alone, or two or more types may be used in any ratio and combination. Further, in consideration of the purpose of each layer, the properties of the selected solvent and dispersion medium, etc., it is preferable to appropriately adjust the physical properties such as the solid content concentration and viscosity of the coating solution within a desired range.

Examples of the solvent or dispersion medium used for preparing a coating solution for coating and forming each layer constituting the photoreceptor include alcohols, ethers, esters, ketones, aromatic hydrocarbons, chlorinated hydrocarbons, and the like. , Nitrogen-containing compounds, aprotic polar solvents, and the like.
Examples of alcohols include methanol, ethanol, propanol, 2-methoxyethanol and the like.
Examples of ethers include tetrahydrofuran, 1,4-dioxane, dimethoxyethane and the like.
Examples of the esters include methyl formate and ethyl acetate.
Examples of ketones include acetone, methyl ethyl ketone, cyclohexanone, and the like.
Examples of aromatic hydrocarbons include benzene, toluene, xylene, and the like.
Examples of chlorinated hydrocarbons include dichloromethane, chloroform, 1,2-dichloroethane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, tetrachloroethane, 1,2-dichloropropane, trichloroethylene, and the like. It is done.
Examples of nitrogen-containing compounds include n-butylamine, isopropanolamine, diethylamine, triethanolamine, ethylenediamine, and triethylenediamine.
Examples of aprotic polar solvents include acetonitrile, N-methylpyrrolidone, N, N-dimethylformamide, dimethyl sulfoxide and the like.

  In addition, said solvent and a dispersion medium are examples, and if it does not restrict | limit the effect of this invention remarkably, it will not be limited to the above.

  As a coating method of the photosensitive layer, for example, a spray coating method, a spiral coating method, a ring coating method, a dip coating method, or the like can be used. As the spray coating method, any known spray method can be used. For example, a method using air spray, airless spray, electrostatic air spray, electrostatic airless spray, rotary atomizing electrostatic spray, hot spray, hot airless spray, or the like can be used. In addition, the application | coating method may be performed individually by 1 type, and may be performed combining 2 or more types arbitrarily.

  Among them, in order to obtain the atomization degree and adhesion efficiency for obtaining a uniform film thickness, in the rotary atomizing electrostatic spray, the conveying method disclosed in the republication No. 1-805198, that is, cylindrical It is preferable that the workpiece is continuously conveyed without being spaced apart in the axial direction while rotating the workpiece. Thereby, it is possible to obtain a photoconductor excellent in film thickness uniformity with an overall high adhesion efficiency.

  As the spiral coating method, any known spiral coating method can be used. For example, a method using an injection coating machine or a curtain coating machine disclosed in Japanese Patent Application Laid-Open No. 52-119651, a paint from a minute opening disclosed in Japanese Patent Application Laid-Open No. A method of flying continuously, a method using a multi-nozzle body disclosed in JP-A-3-193161, and the like can be used.

  As the dip coating method, any method can be used as long as it is a known dip coating method. At this time, in the case of a coating solution for forming a single layer type photosensitive layer and a charge transport layer in a laminated type photosensitive layer, the solid content concentration in the coating solution is usually 5% by weight or more, preferably 10% by weight or more. More preferably, it is in the range of 15% by weight or more, usually 60% by weight or less, preferably 50% by weight or less, more preferably 35% by weight or less. The viscosity of the coating solution is usually 30 mPa · s or higher, preferably 50 mPa · s or higher, more preferably 100 mPa · s or higher, and usually 800 mPa · s or lower, preferably 700 mPa · s or lower, more preferably 500 mPa · s. The range is as follows.

  In the case of a coating solution for forming a charge generation layer in a laminated photosensitive layer, the solid content concentration in the coating solution is usually 0.5% by weight or more, preferably 1% by weight or more, and usually 20% by weight. Hereinafter, it is preferably 15% by weight or less, more preferably 10% by weight or less. The viscosity of the coating solution is preferably 0.1 mPa · s or more, more preferably 0.5 mPa · s or more, and usually 20 mPa · s or less, preferably 10 mPa · s or less, more preferably 5 mPa · s or less. It is a range.

  As a drying method, for example, a hot air dryer, a steam dryer, an infrared dryer, a far-infrared dryer, or the like can be used, but the drying method is not limited thereto. The coating film may be dried at room temperature (usually 25 ° C.) or the drying temperature may be adjusted appropriately. The drying temperature may be a constant temperature or may be varied during the drying process. When adjusting the drying temperature, it is usually 100 ° C or higher, preferably 110 ° C or higher, more preferably 120 ° C or higher, and usually 250 ° C or lower, preferably 170 ° C or lower, more preferably 140 ° C or lower. If the drying temperature is too high, bubbles may be mixed in the photosensitive layer. If the drying temperature is too low, it takes time for drying, and the residual solvent amount may increase to adversely affect the electrical characteristics. Also, the drying time is not limited, and can be arbitrarily set within a range that does not significantly limit the effect of the present invention. In addition, also as a drying method, 1 type may be performed independently and 2 or more types may be performed by arbitrary ratios and combinations.

[3. toner]
In the case of forming an image using the photoconductor of the present invention, any toner can be used. In particular, the use of the first toner and / or the second toner described below has a specific effect. Is preferable. The first toner and the second toner are suitable for use as an electrostatic image developing toner.

[3-1. First toner]
The first toner according to the present invention has an average circularity measured by a flow type particle image analyzer of the first toner of 0.940 or more, preferably 0.942 or more, and 1.000 or less. is there. Since the spherical toner having a high degree of circularity is less likely to get caught between toners or various members, the mechanical share at the charging roller is small, and the surface shape change is slight. Further, since the fluidity of the toner base itself is high, even if the amount of the externally added inorganic powder changes, the fluidity hardly changes greatly. As described above, a toner having a high degree of circularity has a form factor with less toner deterioration. Furthermore, toner having a high degree of circularity is excellent in releasability from the photosensitive member, and therefore has an excellent transfer efficiency, a sufficient image density can be ensured, and a residual toner can be reduced.

  However, toner having a high average circularity tends to increase the weakly charged toner ratio WST [%] measured by the E-SPART analyzer, which indicates that the toner scattering tends to deteriorate. Further, a toner having a high average circularity tends to pass through the cleaning blade when the transfer residual toner is scraped off with a cleaning blade, and tends to cause an image to be stained. In addition, the above phenomenon becomes more remarkable when performing high-speed printing. Therefore, the average circularity of the first toner according to the present invention is preferably 0.99 or less, more preferably 0.98 or less, and still more preferably 0.97 or less. Further, toner having a small particle size and high circularity is difficult to scrape off with a cleaning blade, and the toner easily passes through the cleaning blade. Therefore, the particle size distribution can be controlled particularly according to the circularity. preferable.

[Measurement method and definition of average circularity]
The “average circularity” in the present invention is measured as follows and is defined as follows. That is, the toner base particles are dispersed in a dispersion medium (Isoton II, manufactured by Beckman Coulter, Inc.) in a range of 5720 / μL or more and 7140 / μL or less, and a flow type particle image analyzer (Sysmex Corporation (formerly Toa) Using FPIA2100) manufactured by Medical Electronics Co., Ltd., measurement is performed under the following apparatus conditions, and the value is defined as “average circularity”. In the case where the toner is obtained by fixing or adhering an external additive to the surface of the toner base particles, it is measured as a measurement sample.
・ Mode: HPF
-HPF analysis amount: 0.35 μL
-HPF detection number: 2000-2500

The following is measured by the apparatus and automatically calculated and displayed in the apparatus. The “circularity” is defined by the following equation.
[Circularity] = [Perimeter of a circle with the same area as the projected particle area] / [Perimeter of projected particle image]
Then, 2000 or more and 2500 or less, which is the number of HPF detected, is measured, and the arithmetic average (arithmetic mean) of the circularity of each particle is displayed on the apparatus as “average circularity”.

[3-2. Second toner]
The second toner according to the present invention satisfies all of the following (i) to (iii).
(I) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 μm or less.
(Ii) The average circularity is 0.93 or more.
(Iii) The relationship between the volume median diameter (Dv50) of the toner and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50). Fulfill.

About (i) The volume median diameter (Dv50) of the second toner according to the present invention is 4.0 μm or more and 7.0 μm or less. Within this range, a high-quality image can be sufficiently provided. Among them, from the viewpoint of enabling high-quality image formation, it is preferable that the thickness is preferably 6.8 μm or less, more preferably 6.5 μm or less. Further, from the viewpoint of reducing the amount of very fine toner powder (hereinafter sometimes referred to as “fine powder” as appropriate), it is preferably 4.5 μm or more, more preferably 5.0 μm or more, and particularly preferably 5 μm. .3 μm or more.

[Measurement method and definition of volume median diameter (Dv50)]
The “volume median diameter (Dv50)” in the present invention is measured as follows and is defined as follows.
That is, in a cylindrical polyethylene (PE) beaker having an inner diameter of 47 mm and a height of 51 mm, 0.100 g of toner using a spatula and 20% by mass of sodium dodecylbenzenesulfonate aqueous solution (hereinafter referred to as “DBS aqueous solution” as appropriate) using a dropper. ”) Is mixed. At this time, the toner and the 20% DBS aqueous solution are added only to the bottom of the beaker so that the toner does not scatter on the edge of the beaker.
Next, using a spatula, the toner and the 20% DBS aqueous solution are stirred for 3 minutes until they become a paste. At this time, the toner should be prevented from being scattered on the edge of the beaker.

  Subsequently, 30 g of a dispersion medium (Isoton II, manufactured by Beckman Coulter, Inc.) is mixed, stirred for 2 minutes using a spatula, and the whole is made into a uniform solution visually. Next, a fluororesin-coated rotor having a length of 31 mm and a diameter of 6 mm is placed in a beaker and dispersed using a stirrer at 400 rpm for 20 minutes. At this time, macroscopic particles visually observed at the gas-liquid interface and the edge of the beaker are dropped into the beaker at a rate of once every 3 minutes so as to form a uniform dispersion. Subsequently, this is filtered through a mesh having a mesh size of 63 μm, and the obtained filtrate is defined as a “toner dispersion”.

The volume median diameter (Dv50) of toner is Multisizer III (aperture diameter 100 μm; hereinafter abbreviated as “Multisizer”) manufactured by Beckman Coulter, and Isoton II manufactured by the same company is used as a dispersion medium. The “toner dispersion” is diluted to a dispersoid concentration of 0.03% by mass and measured with Multisizer III analysis software with a KD value of 118.5. The measurement particle size range is from 2.00 to 64.00 μm, and this range is discretized into 256 divisions at equal intervals on a logarithmic scale, and the volume calculated based on the statistical values on the basis of the volume The median diameter (Dv50).
In the case where the toner is obtained by fixing or adhering an external additive to the surface of the toner base particles, it is measured as a measurement sample.

Regarding (ii) The second toner according to the present invention has an average circularity of 0.93 or more and preferably 0.94 or more. Furthermore, it is more preferable to have the same average circularity as the first toner. This is for the same reason as the first toner.
In the second toner according to the present invention, the definition and measurement method of the average circularity is the same as that of the first toner according to the present invention.

Regarding (iii) In the second toner according to the present invention, the relationship between the volume median diameter (Dv50) of the toner and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm is
Dns ≦ 0.233EXP (17.3 / Dv50)
Meet. In the present specification, “EXP” indicates “Exponential”. That is, the base of the natural logarithm, and the right side is the exponent. This formula is sometimes referred to as “requirement (iii) formula”.

  The expression of requirement (iii) is intended to indicate that fine powder increases as the volume median diameter (Dv) of the second toner decreases, and the volume median diameter (Dv) is 4 In the region of .5 μm or less, the volume median diameter (Dv) approaches the region of particle size of 2.00 μm or more and 3.56 μm or less, so that the value of Dns increases exponentially. Such an area of 2.00 μm or more and 3.56 μm or less is an area expressed by a specified channel of Multisizer III manufactured by Coulter Counter.

  In the second toner according to the present invention, the toner particles included in the particle diameter range of 2.00 μm to 3.56 μm have a volume median diameter (Dv) of 4.0 μm to 7.0 μm. This is the particle size range that should be specifically excluded in the region (see requirement (i)), the basis of which follows experimental results.

  The second toner according to the present invention having a particle size distribution satisfying the requirement (iii) provides high image quality, and has little contamination even when a high-speed printing machine is used. (Following flatness) and the like are suppressed, and the cleaning property is excellent. In addition, since the charge amount distribution is very sharp because the particle size distribution is sharp, toner particles with a small charge amount do not cause smearing of the white background portion of the image or scattering to contaminate the inside of the apparatus. In addition, toner particles having a large charge amount do not develop and adhere to members such as a layer regulating blade and a roller to cause image defects such as streaks and blurring, and “selective development” hardly occurs. Note that “selective development” is a phenomenon in which only toner having a charge amount necessary for development is developed and consumed when the toner charge amount distribution is broad.

  That is, the amount of fine powder affects the image with the formula of the requirement (iii) as a boundary. When the value of Dns exceeds the right side in the expression of requirement (iii), fine powder tends to cause defects in the image. For example, as shown in FIG. 2, fine powder may accumulate on the cleaning blade, and afterimages, blurring, dirt, and the like may occur as image defects. FIG. 2 is a 1000 × magnification scanning electron microscope (SEM) photograph showing an example of the state of toner adhesion on the cleaning blade after evaluation of the actual image of the toner.

  An image forming apparatus is usually designed to transfer toner particles having a specific charge amount. For this reason, first, toner particles having such a specific charge amount are preferentially transferred to the photoreceptor during electrostatic development. The toner particles exceeding the specific charge amount may adhere to the member or the like and may be contaminated or fluidity may be deteriorated. On the other hand, toner particles that are less than the specific charge amount may accumulate in the cartridge and contaminate members and the like.

  Here, the toner charge amount correlates with the toner particle size when the toner composition is the same. Generally, the smaller the particle size, the higher the charge amount per unit weight, and the larger the particle amount, the smaller the charge amount per unit weight. Become. That is, when a large amount of toner having a small particle size is present, the charge amount becomes too high, and thus tends to cause adhesion to a member or the like and deterioration of toner fluidity. When the second toner according to the present invention is used, the above-described “selective development” is suppressed. The requirement (iii) is defined by the toner of 3.56 μm or less.

This 3.56 μm is a value defined for the channel of the measuring apparatus. On the other hand, the lower limit value was set to 2.00 μm because of the measurement limit of the measuring apparatus.
That is, the reason why the particle size% (Dns) is specified to be 2.00 μm or more and 3.56 μm or less is used as the lower limit value for measuring the particle size of the second toner according to the present invention. It is a measurement limit of the apparatus, and the upper limit value is a critical value of the effect obtained from the results described in the examples. Accordingly, if the number% of the toner having a particle size larger than 3.56 μm is adopted, it becomes difficult to clearly separate the toner that exhibits the effect of the present invention from the toner that does not exhibit the effect according to the present invention.

Further, in the second toner according to the present invention, the relationship between the volume median diameter (Dv50) and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm is expressed by the following formula (iii-1). Satisfying is preferable from the viewpoint of the effect.
Dns ≦ 0.110EXP (19.9 / Dv50) (iii-1)

On the other hand, in the second toner according to the present invention, the relationship between the volume median diameter (Dv50) and the number% (Dns) of toner having a particle diameter of 2.00 μm or more and 3.56 μm or less is represented by the following formula (iii-2). It is preferable from the viewpoint of producing with good yield.
0.0517EXP (22.4 / Dv50) ≦ Dns (iii-2)

In addition, it is preferable that the second toner according to the present invention has a Dns of 6% by number or less because it can provide a higher quality image or hardly contaminate the image forming apparatus.
Further, the above-described preferred particle diameter ranges of the volume median diameter (Dv50) and Dns, for example, the conditions such as “Dv50 is 4.5 μm or more” and “Dns is 6% by number or less” are satisfied in combination. More preferably. As a result, it is possible to provide a high-quality image without deteriorating the yield from the viewpoint of production, and to realize a toner that hardly contaminates the image forming apparatus and hardly causes “selective development”.

[Measurement Method and Definition of Number% (Dns) of Toner with Particle Size of 2.00 μm to 3.56 μm]
The “number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” in the present invention is measured as follows and is defined as follows.
That is, a cylindrical polyethylene (PE) beaker having an inner diameter of 47 mm and a height of 51 mm is mixed with 0.100 g of toner using a spatula and 0.15 g of a 20 mass% DBS aqueous solution using a dropper. At this time, the toner and the 20% DBS aqueous solution are added only to the bottom of the beaker so that the toner does not scatter on the edge of the beaker.
Next, using a spatula, the toner and the 20% DBS aqueous solution are stirred for 3 minutes until they become a paste. At this time, the toner should be prevented from being scattered on the edge of the beaker.

  Subsequently, 30 g of the dispersion medium Isoton II is mixed and stirred for 2 minutes using a spatula to make the whole visually uniform solution. Next, a fluororesin-coated rotor having a length of 31 mm and a diameter of 6 mm is placed in a beaker and dispersed using a stirrer at 400 rpm for 20 minutes. At this time, macroscopic particles visually observed at the gas-liquid interface and the edge of the beaker are dropped into the beaker at a rate of once every 3 minutes so as to form a uniform dispersion. Subsequently, this is filtered through a mesh having a mesh size of 63 μm, and the obtained filtrate is defined as a “toner dispersion”.

  For the number% (Dns) of the toner having a particle size of 2.00 μm or more and 3.56 μm or less, Multisizer (aperture diameter 100 μm) is used, Isoton II made by the same company is used as a dispersion medium, and the above “toner dispersion liquid” is used. Then, dilute to a dispersoid concentration of 0.03% by mass, and measure with a Multisizer III analysis software with a KD value of 118.5. The lower limit particle size of 2.00 μm is the detection limit of the measuring device multisizer, and the upper limit particle size of 3.56 μm is a prescribed channel value in the measuring device multisizer. In the second toner according to the present invention, an area having a particle diameter of 2.00 μm or more and 3.56 μm or less is recognized as a fine powder area.

The measurement particle size range is from 2.00 μm to 64.00 μm, and this range is discretized into 256 divisions at equal intervals on a logarithmic scale, and 2.00 μm based on the statistical values on the basis of their number. The ratio of the particle size component from 3 to 3.56 μm is calculated on the basis of the number and is defined as “Dns”.
In the case where the toner is obtained by fixing or adhering an external additive to the surface of the toner base particles, it is measured as a measurement sample.

[Advantages of the second toner according to the present invention]
Hereinafter, the advantages of the second toner according to the present invention will be described in comparison with the prior art.
In recent years, the use of image forming apparatuses such as electrophotographic copying machines has been expanded, and the market demand for image quality has been increasing. Particularly in office documents, in addition to the development of mapping technology and latent image forming technology for input, the types of character hieroglyphics are becoming more abundant and finer at the time of output. In addition, with the spread and development of presentation software, the reproducibility of an electrostatic latent image with extremely high image quality, which has few defects and unclearness in printed images, is required. In particular, as a toner used in the case of a line image in which the electrostatic latent image on the photosensitive member constituting the image forming apparatus is 100 μm or less (approximately 300 dpi or more), a conventional toner having a large particle diameter generally has poor thin line reproducibility. The sharpness of the line image is still not sufficient.

  In particular, in an image forming apparatus such as an electrophotographic printer using a digital image signal, an electrostatic latent image is formed by gathering a certain number of dot units, and a solid portion, a halftone portion, and a light portion have a dot density. It is expressed by changing. However, if the toner is not arranged faithfully in the dot unit and the mismatch between the position of the dot unit and the position of the actually placed toner occurs, this corresponds to the ratio of the dot density of the black portion and the white portion of the digital latent image. There is a possibility that the gradation of the toner image cannot be obtained. Further, when the resolution is improved by reducing the dot size in order to improve the image quality, it tends to become more difficult to be faithful to an electrostatic latent image formed from minute dots. For this reason, although the resolution is high, there is an undeniable tendency for the image to have poor gradation and lack sharpness.

In view of this, a technique has been proposed in which the toner particle size distribution is regulated to improve the reproducibility of minute dots and improve the image quality.
For example, JP-A-2-284158 proposes a toner having an average particle diameter of 6 to 8 μm. This technique has attempted to form an electrostatic latent image of fine dots with high reproducibility by reducing the particle size.

Further, for example, Japanese Patent Laid-Open No. 5-119530 discloses a toner mother particle having a toner having a weight average particle diameter of 4 to 8 μm and further containing 17 to 60% by number of toner mother particles having a particle diameter of 5 μm or less. Is described.
Further, for example, JP-A-1-221755 describes a magnetic toner containing 17 to 60 number% of magnetic toner base particles having a particle size of 5 μm or less.

For example, Japanese Patent Laid-Open No. 6-289648 describes toner base particles in which the content of toner base particles having a particle size of 2.0 to 4.0 μm is 15 to 40% by number in the toner particle size distribution. ing.
Furthermore, for example, Japanese Patent Application Laid-Open No. 2001-134005 describes a toner having about 15 to 65% by number of particles of 5 μm or less. Similar toners are also disclosed in JP-A-11-147331 and JP-A-11-362389.

For example, JP-A-2-000877 contains 17 to 60% by number of toner base particles having a particle size of 5 μm or less, and 1 to 30 toner base particles having a particle size of 8 to 12.7 μm. Toner having a specific particle size distribution in a toner having a volume average particle diameter of 4 to 10 μm and a toner having a specific particle size distribution is described. ing.
Further, Japanese Patent Application Laid-Open No. 2004-045948 discloses that in a toner particle having a 50% volume particle diameter of 2 to 8 μm, the number of toner particles having a particle diameter of “0.7 × 50% number particle diameter” or less is 10 number%. It is described that:

  However, all of these toners contain a large number of particles having a particle size of 3.56 μm or less exceeding the upper limit of the right side in the formula of requirement (iii) of the present invention. Is a toner in which a relatively large amount of fine powder remains with respect to toner having a predetermined particle size. In such a toner, since the proportion of fine powder is still large, particularly in a developing method that requires a momentary frictional charging, such as a non-magnetic one-component developing method, a toner that has a fast charge rising is required, toner particles that are not sufficiently charged are generated. Therefore, the toner drops from the developing roller and blows out the toner, the printing history of the first round remains after the second round of the developing roller, and the image density selectively increases and decreases (ghost), the drum cleaning failure, the developing roller Contamination of the printed image may occur due to poor toner layer formation.

  Further, in recent years, along with market demand for image quality, there has been a demand for toner having a long life and high-speed printing. However, these required characteristics have not been sufficiently satisfied with the conventional toner. If there is a lot of fine powder like conventional toner, the fine powder will contaminate the member with continuous printing, the charge imparting ability to the toner will be reduced and the image will be distorted, and if it is introduced into a high speed printer, toner scattering will be noticeable was there.

  Also, in order to provide high image printing, it is desirable that the toner particle size distribution be sharp. This is because, when coarse powder (that is, very large toner particles) is contained, the toner charge amount distribution becomes broad and “selective development” occurs. When the selection phenomenon occurs, a good image can be obtained at the initial stage of image formation. However, as the image formation continues, the density may gradually decrease or the particle size of the toner may increase, resulting in a sticky image. . Such a phenomenon is said to be inferior in selective developability. Furthermore, the coarse powder having a low charge amount tends to significantly reduce the guaranteed life number. Japanese Patent Application Laid-Open No. 2003-255567 discloses a toner having a large number of coarse powders with a number variation coefficient of 24.2%. Such a toner is not suitable for stably providing a high-resolution image. In addition, International Publication No. 2004-088431 pamphlet does not indicate that the particle size distribution is sharp.

  Further, it is desirable to pay attention to toner transfer characteristics in order to realize high-quality image formation. The toner having high transfer characteristics refers to toner having high transfer efficiency of toner particles developed on the photoreceptor to the intermediate transfer drum or paper, or high transfer efficiency from the intermediate transfer drum to paper. However, JP-A-7-098521, JP-A-2006-091175, and JP-A-2006-119616 describe pulverized toner having a high average circularity from the viewpoint of the manufacturing process, and have high transfer characteristics. Insufficient to provide quality printing.

  As described above, the toner used in the conventional image forming apparatus does not satisfy any of the above requirements (i) to (iii). The reason for this is that if the amount of fine powder is reduced as much as possible (that is, if the requirement (iii) is satisfied), the generation of coarse powder tends to occur. Further, trying to round the toner by physical impact (that is, satisfying the requirement (ii)) promotes the generation of fine powder (that is, the requirement (iii) is not satisfied). This is because the. Furthermore, if the toner is intended to be circularized by thermal fusion (that is, if the requirement (ii) is satisfied), toner particles tend to be fused with each other and coarse powder tends to be generated.

  On the other hand, the second toner according to the present invention satisfies all of the above (i) to (iii). The second toner that satisfies all the requirements (i), (ii), and (iii) according to the present invention can obtain high image quality, and has little stains even when used in a high-speed printing machine, resulting in an afterimage (ghost). In addition, it suppresses blurring (solid followability) and is excellent in cleaning properties. In addition, since the charge amount distribution is very sharp because the particle size distribution is sharp, particles with a small charge amount do not cause the white background portion of the image to be smeared or scattered to stain the inside of the apparatus, Toner particles having a large charge amount are not developed and adhere to members such as a layer regulating blade and a roller, and image defects such as streaks and blurring are not caused. That is, the “selective development” described above is unlikely to occur.

  In particular, the second toner according to the present invention has a very sharp charge amount distribution as compared with the conventional toner. The charge amount distribution has a correlation with the particle size distribution of the toner. When the toner has a broad particle size distribution like a conventional toner, the charge amount distribution is also broad. When the charge amount distribution becomes broad, the ratio of particles with low charge or particles with high charge that cannot be controlled by the developing conditions of the image forming apparatus for the toner increases, causing various image defects. . For example, toner particles with a small charge amount cause smearing of the white background of the image or scattering in the apparatus, causing smearing. In addition, toner particles having a large charge amount accumulate on members such as a layer regulating blade and a roller in a developing tank without being developed, and cause image defects such as streaks and blurring due to fusion.

  This is because the development process conditions are set so as to match the average value of the toner charge amount in the design of the development process in the image forming apparatus. This is because the image forming apparatus tends to cause image defects such as scattering and streaks. Therefore, the toner having a broad particle size distribution does not match well with the image forming apparatus. On the other hand, if the charge amount distribution is sharp as in the second toner according to the present invention, the developability can be controlled by bias adjustment or the like, and the image forming apparatus member is not contaminated. An image can be given.

  The “standard deviation of charge amount”, which is one of the values indicating the “charge amount distribution” of the second toner according to the present invention, is preferably 1.0 or more, more preferably 1.3 or more, and 2. 0 or less is preferable, 1.8 or less is more preferable, and 1.5 or less is particularly preferable. When the upper limit is exceeded, toner adheres to the layer regulation blade and is difficult to be transported, and the adhered toner may further block the transported toner and contaminate members in the image forming apparatus. On the other hand, when the value falls below the lower limit, it may not be preferable from an industrial viewpoint.

  As described above, since the second toner according to the present invention has a sharp charge amount distribution, the contamination (toner scattering) in the image forming apparatus caused by the poorly charged toner is very small. This effect is remarkably exhibited particularly in a high-speed type image forming apparatus in which the developing process speed to the photosensitive member is 100 mm / second or more.

In addition, the second toner according to the present invention has a sharp charge amount distribution, so that the developability is very good, and toner particles that accumulate without being developed are very few. This is particularly effective in an image forming apparatus having a high toner consumption speed. Specifically, a toner used in an image forming apparatus that satisfies the following formula (iv) is preferable in order to sufficiently exhibit the effects of the present invention.
Warranty life sheet number (sheets) x printing rate ≧ 400 (sheets) of toner filling machine (iv)
In the formula (iv), the “printing rate” is represented by a value obtained by dividing the sum of the printed portion areas by the total area of the printing medium in the printed matter for determining the guaranteed lifetime number that is the performance of the image forming apparatus. The “print rate” of the print% of “5%” is “0.05”.

  Furthermore, since the second toner according to the present invention has a very sharp particle size distribution, the reproducibility of the electrostatic latent image is very good. Therefore, the effect of the second toner according to the present invention is sufficiently exhibited particularly when used in an image forming apparatus having a resolution of 600 dpi or more on the photosensitive member. Further, by using such toner, the image forming apparatus can provide a high-resolution image with a resolution of 600 dpi or more on the photosensitive member. “Resolution to photoconductor” is the same as “resolution of device”.

[3-3. Other physical properties of toner according to the present invention]
The toner according to the present invention, such as the first toner and the second toner according to the present invention, preferably has the physical properties described below in addition to the physical properties described above.

  Among the peak molecular weights of the toner according to the present invention in gel permeation chromatography (hereinafter sometimes abbreviated as “GPC”) of a soluble content in tetrahydrofuran (hereinafter sometimes abbreviated as “THF” where appropriate), at least One is preferably 30,000 or more, more preferably 40,000 or more, still more preferably 50,000 or more, preferably 200,000 or less, more preferably 150,000 or less, and even more preferably 100,000 or less. 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.

  Further, the chargeability of the toner according to the present invention may be positively charged or negatively charged, but is preferably used as a negatively chargeable toner. Control of the chargeability of the toner can be adjusted by selection and content of the charge control agent, selection and blending amount of the external additive, and the like.

[3-4. Configuration of Toner According to the Present Invention]
Each of the toners according to the present invention, such as the first toner and the second toner according to the present invention, is configured by appropriately selecting a binder resin, a colorant, a wax, an external additive, and the like.
The binder resin may be appropriately selected from those known to be used for toner. For example, styrene resin, vinyl chloride resin, rosin modified maleic acid resin, phenol resin, epoxy resin, saturated or unsaturated polyester resin, polyethylene resin, polypropylene resin, ionomer resin, polyurethane resin, silicone resin, ketone resin, Ethylene-acrylate copolymer, xylene resin, polyvinyl butyral resin, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-anhydrous malein An acid copolymer etc. can be mentioned. These resins may be used alone or in combination of two or more in any combination and ratio.

  The colorant constituting the toner according to the present invention may be appropriately selected from those known to be usable for toner. For example, yellow pigments, magenta pigments, and cyan pigments shown below can be used. As black pigments, carbon black or a mixture of the following yellow pigments / magenta pigments / cyan pigments toned to black is used. .

  Among these, carbon black as a black pigment exists as an aggregate of very fine primary particles, and when dispersed as a pigment dispersion, particle coarsening due to reaggregation tends to occur. The degree of reagglomeration of carbon black particles correlates with the amount of impurities contained in carbon black (the degree of residual undecomposed organic matter). If there are many impurities, coarsening due to reaggregation after dispersion tends to be severe. Indicates. As a quantitative evaluation of the amount of impurities, the ultraviolet absorbance of the toluene extract of carbon black measured by the following method is preferably 0.05 or less, and more preferably 0.03 or less. Generally, carbon black produced by the channel method tends to have a large amount of impurities, so that carbon black produced by the furnace method is preferred.

  The ultraviolet absorbance (λc) of carbon black is measured by the following method. First, 3 g of carbon black was sufficiently dispersed and mixed in 30 mL of toluene. Filter using 5C filter paper. Thereafter, the filtrate was put in a quartz cell having a 1 cm square light absorption part, and the value (λs) measured for absorbance at a wavelength of 336 nm using a commercially available ultraviolet spectrophotometer, and the value obtained by measuring the absorbance of toluene alone as a reference using the same method. From (λo), the ultraviolet absorbance is obtained by λc = λs−λo. Examples of commercially available spectrophotometers include an ultraviolet-visible spectrophotometer (UV-3100PC) manufactured by Shimadzu Corporation.

  As the yellow pigment, for example, a compound represented by a condensed azo compound, an isoindolinone compound or the like is used. As a specific example, C.I. I. CI Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 150, 155, 168, 180, 194, etc. are preferably used. It is done.

  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. As a specific example, 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, 17.3, 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. 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. As a specific example, C.I. I. Pigment blue 1, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 and the like; I. Pigment Green 7, 36, etc. can be used particularly preferably.
In addition, a colorant may be used individually by 1 type and may be used 2 or more types by arbitrary combinations and ratios.

  The toner according to the present invention preferably contains a wax for imparting releasability. Any wax can be used as long as it has releasability, and is not particularly limited. Specific examples include olefin waxes such as low molecular weight polyethylene, low molecular weight polypropylene and copolymer polyethylene; paraffin wax; ester waxes having a long-chain aliphatic group such as behenyl behenate, montanate ester, stearyl stearate; Plant waxes such as hydrogenated castor oil and carnauba wax; ketones having long chain alkyl groups such as distearyl ketone; silicones having alkyl groups; higher fatty acids such as stearic acid; long chain aliphatic alcohols such as eicosanol; glycerin and penta Examples include carboxylic acid esters or partial esters of polyhydric alcohols obtained from polyhydric alcohols such as erythritol and long chain fatty acids; higher fatty acid amides such as oleic acid amide and stearic acid amide; low molecular weight polyesters and the like.

  In order to improve the fixability among these waxes, the melting point of the wax is preferably 30 ° C. or higher, more preferably 40 ° C. or higher, and particularly preferably 50 ° C. or higher. Moreover, 100 degrees C or less is preferable, 90 degrees C or less is still more preferable, and 80 degrees C or less is especially preferable. If the melting point is too low, the wax tends to be exposed and sticky after fixing, and if the melting point is too high, the fixability at low temperatures tends to be poor. Furthermore, as the wax compound species, ester waxes obtained from aliphatic carboxylic acids and mono- or polyhydric alcohols are preferred, and ester waxes having 20 to 100 carbon atoms are preferred.

  The said wax may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. Further, the melting point of the wax compound can be appropriately selected depending on the fixing temperature for fixing the toner. The amount of the wax used is preferably 4 parts by weight or more, more preferably 6 parts by weight or more, particularly preferably 8 parts by weight or more, preferably 20 parts by weight or less, more preferably 18 parts by weight with respect to 100 parts by weight of the toner. Or less, particularly preferably 15 parts by weight or less.

  When the volume median diameter (Dv50) of the toner is 7 μm or less, that is, when the toner has a small particle size, the exposure of the wax to the toner surface becomes extremely intense as the amount of wax used increases. The storage stability of the toner tends to deteriorate. The second toner according to the present invention has a sharp particle size distribution that does not cause deterioration of the toner characteristics as compared with the conventional toner even when the amount of wax used is large as in the above range. The toner has a particle size.

  The toner according to the present invention may be one in which a known external additive is blended on the surface of the toner base particles in order to control fluidity and developability. Examples of the external additive include metal oxides and hydroxides such as alumina, silica, titania, zinc oxide, zirconium oxide, cerium oxide, talc, hydrotalcite; calcium titanate, strontium titanate, barium titanate, etc. Metal nitrides such as titanium nitride and silicon nitride; carbides such as titanium carbide and silicon carbide; organic particles such as acrylic resins and melamine resins; Among these, silica, titania, and alumina are preferable, and those that have been surface-treated with, for example, a silane coupling agent or silicone oil are more preferable. In addition, only 1 type may be used for an external additive, and it may combine 2 or more types by arbitrary combinations and a ratio.

The average primary particle size of the external additive is usually 1 nm or more, preferably 5 nm or more, and usually 500 nm or less, preferably 100 nm or less. It is also preferable to use a combination of a small particle size and a large particle size in the particle size range.
The total amount of the external additive is usually 0.05 parts by weight or more, preferably 0.1 parts by weight or more, and usually 10 parts by weight or less, preferably 5 parts by weight with respect to 100 parts by weight of the toner base particles. It is as follows.

  By the way, the toner according to the present invention can be used for a magnetic two-component development system in which a carrier for conveying the toner to the electrostatic latent image portion by a magnetic force coexists, or a magnetic one-component development in which magnetic powder is contained in the toner. It may be used for either a non-magnetic one-component development method that does not use magnetic powder in the toner, but in order to exhibit the effects of the present invention remarkably, it is particularly suitable for a non-magnetic one-component development method. It is preferably used as a toner.

When used as a toner for the magnetic two-component development system, the carrier that can be mixed with the toner is a known magnetic substance such as an iron powder type, ferrite type, or magnetite type carrier; A magnetic resin carrier or the like can be used. 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. In addition, a carrier may use only 1 type and may use 2 or more types together by arbitrary combinations and a ratio.
The average particle size of the carrier is not particularly limited, but those having an average particle size of 10 μm to 200 μm are preferable.
These carriers are preferably used in an amount of 5 to 100 parts by weight per 1 part by weight of the toner.

[3-5. Toner production method]
The method for producing the toner according to the present invention is not particularly limited. For example, the toner is produced by a pulverization method, a method of forming particles in a wet medium (hereinafter sometimes abbreviated as “wet method”), or the like. Can do. As the wet method, a method of performing radical polymerization in a wet medium such as a suspension polymerization method or an emulsion polymerization aggregation method (hereinafter abbreviated as “polymerization method”, and the obtained toner may be abbreviated as “polymerization toner”). And a chemical pulverization method typified by a melt suspension method can be preferably used.
Further, there is no particular limitation on the method for making the toner have a particle size in a specific range according to the present invention. For example, in the production process of the polymerized toner, in the case of the suspension polymerization method, a method in which a high shearing force is applied in the process in which polymerizable monomer droplets are generated, or a dispersion stabilizer or the like is increased.

  When toner is produced by a pulverization method, it is generally preferable to perform a classification step because fine powder is likely to be generated. In particular, in order to satisfy the toner particle size requirement according to the present invention, an excessive classification operation may be necessary in the pulverization method, and the yield may be significantly reduced. However, the pulverized toner is not excluded as the toner used in the image forming apparatus of the present invention. On the other hand, the toner according to the present invention is a toner obtained by a wet method in which particles are formed in a wet medium, that is, a toner manufactured in a wet medium, from the viewpoint that a fine powder is hardly generated and a classification step is not essential. Preferably there is.

  As a method for obtaining a toner having a specific particle size distribution according to the present invention, any of a pulverization method; a polymerization method such as a suspension polymerization method and an emulsion polymerization aggregation method; a chemical pulverization method typified by a melt suspension method, etc. Manufacturing methods can also be used. However, in the “pulverization method”, “suspension polymerization method”, and “chemical pulverization method represented by the melt suspension method”, in order to adjust the particle diameter of the toner from a larger size to a smaller size, When trying to reduce the particle size, the proportion of the particles on the small particle side tends to increase, and an excessive burden is imposed on the classification step and the like. In contrast, the emulsion polymerization agglomeration method has a relatively sharp particle size distribution and is adjusted from a size smaller than the diameter of the toner base particles to a larger size. A toner having a diameter distribution is obtained. Therefore, it is particularly preferable to produce the toner according to the present invention by the emulsion polymerization aggregation method for the above reasons.

[Method for producing toner by emulsion polymerization aggregation method]
The following is a method for producing particles by performing polymerization in a wet medium from the viewpoint of hardly generating fine powder among methods for forming particles in a wet medium, and further a method for producing particles by emulsion polymerization aggregation method Will be described. When a toner is produced by an emulsion polymerization aggregation method, a polymerization process, a mixing process, an aggregation process, an aging process (rounding process), and a washing / drying process are usually performed. That is, generally, a dispersion liquid containing primary polymer particles obtained by emulsion polymerization is mixed with a dispersion liquid such as a colorant, a charge control agent, and wax, and the primary particles in the dispersion liquid are aggregated to form core particles. Then, if necessary, the toner base particles can be obtained by washing and drying the particles obtained by fusing and adhering the resin fine particles or the like as necessary.

(Polymerization process)
In this production method, usually, a polymerization step for producing polymer primary particles by emulsion polymerization is performed. Usually, a raw material polymerizable monomer is polymerized by emulsion polymerization to produce polymer primary particles containing a desired binder resin.
As the binder resin constituting the polymer primary particles used in the emulsion polymerization aggregation method, one or two or more polymerizable monomers that can be polymerized by the emulsion polymerization method are appropriately used, and those obtained by emulsion polymerization of the polymerizable monomer are used. What is necessary is just to use. Examples of the polymerizable monomer include “a polymerizable monomer having an acidic group” (hereinafter sometimes simply referred to as “acidic monomer”), “a polymerizable monomer having a basic group” (hereinafter simply referred to as “basic monomer”). "Polymerizable monomer having a polar group" (hereinafter sometimes referred to simply as "polar monomer") and "polymerizability having neither an acidic group nor a basic group" It is preferable to use “monomer” (hereinafter sometimes referred to as “other monomer”) as a raw material polymerizable monomer. At this time, each polymerizable monomer may be mixed separately, or a plurality of polymerizable monomers may be mixed in advance and then mixed simultaneously. Further, it is possible to change the composition of the polymerizable monomer during the mixing of the polymerizable monomer. The polymerizable monomer may be mixed as it is, or may be mixed as an emulsion prepared by mixing with water or an emulsifier in advance.

  Examples of the “acidic monomer” include polymerizable monomers having a carboxyl group such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and cinnamic acid; polymerizable monomers having a sulfonic acid group such as sulfonated styrene A polymerizable monomer having a sulfonamide group such as vinylbenzenesulfonamide; Examples of the “basic monomer” include aromatic vinyl compounds having an amino group such as aminostyrene; nitrogen-containing heterocyclic ring-containing polymerizable monomers such as vinylpyridine and vinylpyrrolidone; These polar monomers may be used alone or in combination of two or more in any combination and ratio. Furthermore, it may exist as a salt with a counter ion. Among these, it is preferable to use an acidic monomer, and (meth) acrylic acid is more preferable.

  The ratio of the total amount of polar monomers in 100% by mass of all polymerizable monomers constituting the binder resin as the polymer primary particles is preferably 0.05% by mass or more, more preferably 0.3% by mass or more, and further Preferably it is 0.5 mass% or more, Especially preferably, it is 1 mass% or more, Preferably it is 10 mass% or less, More preferably, it is 5 mass% or less, More preferably, it is 2 mass% or less. When it is in the above range, the dispersion stability of the obtained polymer primary particles is improved, and the particle shape and particle size can be easily adjusted in the aggregation process.

Examples of the “other monomer” include styrenes such as styrene, methylstyrene, chlorostyrene, dichlorostyrene, p-tert-butylstyrene, pn-butylstyrene, pn-nonylstyrene; methyl acrylate, Acrylic esters such as ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, hydroxyethyl acrylate, ethylhexyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate , Methacrylates such as isobutyl methacrylate, hydroxyethyl methacrylate, ethylhexyl methacrylate; acrylamide, N-propylacrylamide, N, N-dimethylacrylamide, N, N-dipropylacrylic acid De, N, N-dibutyl acrylamide, acrylic acid amides, such as acrylic acid amide; and the like.
In addition, a polymerizable monomer may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  Among the above-described polymerizable monomers used in combination, as a preferred embodiment, an acidic monomer and other monomers may be used in combination. More preferably, (meth) acrylic acid is used as the acidic monomer, and a polymerizable monomer selected from styrenes and (meth) acrylic acid esters is used as the other monomer. It is preferable to use (meth) acrylic acid as the monomer, and use a combination of styrene and (meth) acrylic acid esters as the other monomer, and particularly preferably use (meth) acrylic acid as the acidic monomer. As a combination of styrene and n-butyl acrylate.

  Furthermore, it is also preferable to use a crosslinked resin as the binder resin constituting the polymer primary particles. In that case, as a crosslinking agent shared with the above-mentioned polymerizable monomer, for example, a polyfunctional monomer having radical polymerizability is used. 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 acrylate, diallyl phthalate, and the like. Is mentioned. In addition, a polymerizable monomer having a reactive group in a pendant group such as glycidyl methacrylate, methylol acrylamide, acrolein or the like can be used as a crosslinking agent. Among them, radically polymerizable bifunctional monomers are preferable, and divinylbenzene and hexanediol diacrylate are particularly preferable.

These crosslinking agents such as multifunctional monomers may be used alone or in combination of two or more in any combination and ratio.
When a crosslinked resin is used as the binder resin constituting the polymer primary particles, the blending ratio of the crosslinking agent such as a polyfunctional monomer in the total polymerizable monomer constituting the binder resin is preferably 0.005% by mass or more. More preferably, it is 0.1 mass% or more, More preferably, it is 0.3 mass% or more, Preferably it is 5 mass% or less, More preferably, it is 3 mass% or less, More preferably, it is 1 mass% or less.

  Known emulsifiers can be used for the emulsion polymerization. For example, one or more emulsifiers selected from cationic surfactants, anionic surfactants and nonionic surfactants are used in combination. Can be used.

  Examples of the cationic surfactant include dodecyl ammonium chloride, dodecyl ammonium bromide, dodecyl trimethyl ammonium bromide, dodecyl pyridinium chloride, dodecyl pyridinium bromide, hexadecyl trimethyl ammonium bromide and the like.

  Examples of the anionic surfactant include fatty acid soaps such as sodium stearate and sodium dodecanoate, sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and sodium lauryl sulfate.

  Nonionic surfactants include, for example, polyoxyethylene dodecyl ether, polyoxyethylene hexadecyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl ether, polyoxyethylene sorbitan monooleate ether, monodecanoyl sucrose, etc. Is mentioned.

  The amount of the emulsifier is usually 1 to 10 parts by weight with respect to 100 parts by weight of the polymerizable monomer. Moreover, 1 type, or 2 or more types, such as cellulose derivatives, such as polyvinyl alcohols, such as a partial or complete saponified polyvinyl alcohol, and hydroxyethyl cellulose, can be used together with these emulsifiers as a protective colloid.

Examples of the polymerization initiator include hydrogen peroxide; persulfates such as potassium persulfate; organic peroxides such as benzoyl peroxide and lauroyl peroxide; 2,2′-azobisisobutyronitrile; Azo compounds such as 2′-azobis (2,4-dimethylvaleronitrile); redox initiators and the like are used. In addition, a polymerization initiator may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.
The polymerization initiator is usually used in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of the polymerizable monomer. Especially, as a polymerization initiator, it is preferable that at least one part or all is hydrogen peroxide or organic peroxides.

  Any of the polymerization initiators may be mixed into the polymerization system at any time before, simultaneously with, and after mixing of the polymerizable monomers, and these mixing methods may be combined as necessary.

In the emulsion polymerization, a known chain transfer agent can be used as necessary. Specific examples of the chain transfer agent include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropyl xanthogen, carbon tetrachloride, trichlorobromomethane and the like. A chain transfer agent may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. The amount used is usually 5% by mass or less based on the total polymerizable monomer.
Moreover, a pH adjuster, a polymerization degree adjuster, an antifoaming agent, etc. can be further mix | blended with a reaction system suitably.

  In the emulsion polymerization, the polymerizable monomer is polymerized in the presence of a polymerization initiator. The polymerization temperature is usually 50 ° C. or higher, preferably 60 ° C. or higher, more preferably 70 ° C. or higher, and usually 120 ° C. or lower. Preferably it is 100 degrees C or less, More preferably, it is 90 degrees C or less.

  The volume average diameter (Mv) of the polymer primary particles obtained by emulsion polymerization 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, it is 1 μm or less. When the particle size is less than the above range, it may be difficult to control the aggregation rate. When the particle size exceeds the above range, the particle size of the toner obtained by aggregation tends to be large, and a toner having a target particle size can be obtained. It can be difficult.

  The glass transition temperature by DSC method (differential scanning calorimetry) of the binder resin as the polymer primary particles is preferably 40 ° C. or higher, more preferably 55 ° C. or higher, preferably 80 ° C. or lower, more preferably 65 ° C. It is as follows. Within this range, the storage stability is good and, in addition, the cohesiveness is not impaired. If the glass transition temperature is too high, the cohesiveness of the polymer primary particles is poor, and there is a tendency to use an aggregating agent excessively or to increase the agglomerating temperature excessively, resulting in generation of fine powder. May be easier to do. Here, if the glass transition temperature of the binder resin overlaps with the heat amount change based on other components, for example, the melting peak of polylactone or wax, and cannot be clearly determined, the toner is removed in a state where such other components are excluded. It shall mean the glass transition temperature when produced.

  The acid value of the binder resin constituting the polymer primary particles is preferably 3 mgKOH / g or more, more preferably 5 mgKOH / g or more, preferably 50 mgKOH / g or less, more preferably as a value measured by the method of JIS K0070. Is 30 mgKOH / g or less.

  The lower limit of the solid content concentration of the polymer primary particles in the “polymer primary particle dispersion” is preferably 14% by mass or more, more preferably 21% by mass or more, while the upper limit thereof. The value is preferably 30% by mass or less, and more preferably 25% by mass or less. When it is within the above range, it is easy to adjust the aggregation rate of the polymer primary particles empirically in the aggregation process, and as a result, it is easy to adjust the particle size, particle shape, and particle size distribution of the core particles to an arbitrary range. It becomes.

(Mixing process)
In this production method, after the polymerization step, it is preferable to perform a mixing step of mixing a dispersion containing a colorant, a charge control agent, a wax and the like into a dispersion containing polymer primary particles obtained by emulsion polymerization. . As a result, the primary particles in the dispersion liquid are agglomerated to form core particles (preferably after a shell coating step for fixing or adhering resin fine particles or the like), and the obtained particles are washed and dried. By doing so, toner mother particles can be obtained.

  The colorant is not particularly limited as long as it is a commonly used colorant. Examples thereof include the pigments described above, carbon black such as furnace black and lamp black, and magnetic colorants. The content ratio of the colorant may be an amount sufficient for the obtained toner to form a visible image by development, and is preferably 1 part by weight or more, more preferably 3 parts by weight or more in the toner, Moreover, 25 weight part or less is preferable, 15 weight part or less is more preferable, and 12 weight part or less is especially preferable.

The colorant may be a magnetic colorant having magnetism. The printer, ferromagnetic substance showing ferrimagnetism or ferromagnetism at 0 around ° C. to 60 ° C. is the operating temperature of the copier or the like, specifically magnetic colorant, for example, magnetite (Fe 3 _{O 4),} Maghematite (γ-Fe ₂ O ₃ ), intermediates and mixtures of magnetite and maghemite, M _x Fe _3-x O ₄ , where M is Mg, Mn, Fe, Co, Ni, Cu, Zn represents Cd or the like.) spinel _{ferrite, BaO · 6Fe 2 O 3,} 6 -cubic ferrite such as _{SrO · 6Fe 2 O 3, Y} 3 Fe 5 O 12, Sm 3 Fe 5 O garnet-type oxides such as ₁₂ , rutile-type oxide such as CrO _2, and, Cr, Mn, Fe, Co, include those exhibiting magnetism in the vicinity of 0 ° C. to 60 ° C. of such metal or their ferromagnetic alloys such as Ni, medium Also, magnetite, intermediates maghemite or magnetite and maghemite are preferred.
In addition, a coloring agent may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  When it is contained from the viewpoint of preventing scattering and charging control while having the characteristics as a non-magnetic toner, the content of the magnetic powder in the toner is usually 0.2% by mass or more, preferably 0.5% by mass. % Or more, more preferably 1% by mass or more, and usually 10% by mass or less, preferably 8% by mass or less, more preferably 5% by mass or less. When used as a magnetic toner, the content of the magnetic powder in the toner is usually 15% by mass or more, preferably 20% by mass or more, and usually 70% by mass or less, preferably 60% by mass or less. . If the content of the magnetic powder is less than the above range, the magnetic force required for the magnetic toner may not be obtained, and if it exceeds the above range, it may cause poor fixing properties.

  As a blending method of the colorant in the emulsion polymerization aggregation method, usually, a polymer primary particle dispersion and a colorant dispersion are mixed to form a mixed dispersion, and then aggregated to obtain a particle aggregate. The colorant is preferably used in the state of being emulsified in water by a mechanical means such as a sand mill or a bead mill in the presence of an emulsifier. In this case, it is preferable that the colorant dispersion is added in an amount of 10 to 30 parts by weight, and 1 to 15 parts by weight of an emulsifier with respect to 100 parts by weight of water. In addition, it mix | blends, monitoring the particle size of the coloring agent in a dispersion liquid in the middle of dispersion | distribution, and the volume average diameter (Mv) finally becomes like this. Preferably it is 0.01 micrometer or more, More preferably, it is 0.05 micrometer or more, It is preferable to control within a range of preferably 3 μm or less, more preferably 0.5 μm or less. The blending of the colorant dispersion at the time of emulsion aggregation is usually calculated and used so as to be 2% by mass or more and 10% by mass or less in the finished toner mother particles after aggregation.

  The toner preferably contains a wax in order to improve the fixing property. The wax may be contained in the polymer primary particles or in the resin fine particles. However, as the amount of wax used increases, the aggregation control tends to deteriorate and the particle size distribution tends to become broader. Therefore, as a method of blending the wax in the emulsion polymerization aggregation method, a wax dispersion in which the volume average diameter (Mv) is usually 0.01 μm or more in water and usually emulsified and dispersed to 2.0 μm or less, preferably 0.5 μm or less. It is preferable that the liquid is mixed at the time of emulsion polymerization or mixed in the aggregation process. In order to disperse the wax with a suitable dispersed particle size in the toner, it is preferable to mix the wax as a seed during emulsion polymerization. By mixing as a seed, polymer primary particles in which wax is encapsulated are obtained, so that a large amount of wax does not exist on the surface of the toner, and deterioration of chargeability and heat resistance of the toner can be suppressed. The wax content in the polymer primary particles is preferably 4% by mass or more, more preferably 5% by mass or more, particularly preferably 7% by mass or more, preferably 30% by mass or less, more preferably 20% by mass or less. Especially preferably, it is 15 mass% or less.

  Further, wax may be included in the resin fine particles. In this case as well, as in the case of obtaining polymer primary particles, it is preferable to mix with wax as a seed during emulsion polymerization. The content ratio of the wax in the entire resin fine particles is preferably smaller than the content ratio of the wax in the entire polymer primary particles. Generally, when wax is contained in resin fine particles, the fixability is improved, but on the other hand, the generation amount of fine powder tends to increase. The reason for this is that the fixability is improved because the speed of movement of the wax to the toner surface is increased when heat is applied, but the inclusion of the wax in the resin fine particles broadens the particle size distribution of the resin fine particles. It is considered that the aggregation control becomes difficult, and as a result, an increase in fine powder is caused.

The toner according to the present invention may be blended with a charge control agent in order to impart charge amount and charge stability. As the charge control agent, conventionally known compounds are usually used. Examples thereof include hydroxycarboxylic acid metal complexes, azo compound metal complexes, naphthol compounds, naphthol compound metal compounds, nigrosine dyes, quaternary ammonium salts, and mixtures thereof. In addition, a charge control agent may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.
The blending amount of the charge control agent is preferably in the range of 0.1 to 5 parts by weight with respect to 100 parts by weight of the resin.

  When a charge control agent is contained in the toner in the emulsion polymerization aggregation method, the charge control agent is blended with a polymerizable monomer or the like at the time of emulsion polymerization, or is blended in the aggregation process with the polymer primary particles and the colorant. The blended primary particles, the colorant, and the like can be blended by a method such as blending after agglomeration to obtain an appropriate particle size as a toner. Among these, the charge control agent is preferably emulsified and dispersed in water using an emulsifier, and used as an emulsified dispersion having a volume average diameter (Mv) of 0.01 μm to 3 μm. The blend of the charge control agent dispersion at the time of emulsion aggregation is calculated and used so that it becomes 0.1 mass% or more and 5 mass% or less in the finished toner base particles after aggregation.

  The volume average diameter (Mv) of the polymer primary particles, resin fine particles, colorant particles, wax particles, charge control agent particles, etc. in the dispersion is measured using a nanotrack by the method described in Examples. , Defined as its measured value.

(Aggregation process)
After the mixing step, an aggregating step for aggregating primary particles in the dispersion obtained in the mixing step is usually performed.
In the aggregation step in the emulsion polymerization aggregation method, the above-described primary polymer particles, resin fine particles, colorant particles, and charge components such as a charge control agent and wax are mixed at the same time or sequentially. It is possible to prepare a dispersion of the above components, that is, a polymer primary particle dispersion, a resin fine particle dispersion, a colorant particle dispersion, a charge control agent dispersion, and a wax fine particle dispersion. It is preferable from the viewpoint of uniformity.

  Also, when mixing these different types of dispersions, the components contained in each dispersion have different aggregation rates, and in order to achieve uniform aggregation, mix them over a certain period of time, either continuously or intermittently. It is preferable to do. The suitable time required for mixing varies depending on the amount of the dispersion to be mixed, the solid concentration, and the like. For example, when the colorant particle dispersion is mixed with the polymer primary particle dispersion, it is preferable to mix for 3 minutes or more. Further, when mixing the resin fine particle dispersion with the core particles, it is preferable to mix them over 3 minutes.

  The agglomeration treatment includes a method of mixing an electrolyte, a method of heating, a method of reducing the concentration of an emulsifier in the system, a method of combining these, etc. When primary particles are agglomerated under stirring to obtain particle agglomerates that are approximately the size of the toner, the particle size of the particle agglomerates is controlled from the balance between the agglomeration force between the particles and the shearing force due to agitation. However, the cohesive force can be increased by the above method.

The electrolyte in the case of agglomerating by mixing the electrolyte may be either an organic salt or an inorganic salt. For example, NaCl, KCl, LiCl, Na ₂ SO ₄ , K ₂ SO ₄ , Li ₂ SO ₄ , CH ₃ Inorganic salt having a monovalent metal cation such as COONa, C ₆ H ₅ SO ₃ Na; Inorganic salt having a divalent metal cation such as MgCl ₂ , CaCl ₂ , MgSO ₄ , CaSO ₄ , ZnSO ₄ ; Al ₂ ( And inorganic salts having a trivalent metal cation such as SO ₄ ) ₃ and Fe ₂ (SO ₄ ) ₃ . Among these, when an inorganic salt having a divalent or higher polyvalent metal cation is used, it is preferable from the viewpoint of productivity because the aggregation rate is increased. As a result, fine powder that does not reach the desired toner particle size is likely to be generated. Therefore, it is preferable to use an inorganic salt having a monovalent metal cation that does not have a strong aggregating action, because the amount of fine powder generated can be suppressed.
In addition, an electrolyte may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The amount of the electrolyte used varies depending on the type of electrolyte, the target particle size, etc., but is usually 0.05 parts by weight or more, preferably 0.1 parts by weight or more with respect to 100 parts by weight of the solid component of the mixed dispersion. It is usually 25 parts by weight or less, preferably 15 parts by weight or less, more preferably 10 parts by weight or less. If the amount used is less than the above range, the progress of the agglomeration reaction may be delayed, and a fine powder of 1 μm or less may remain after the agglomeration reaction, or the average particle size of the obtained particle aggregate may not reach the target particle size. When the amount exceeds the above range, rapid agglomeration tends to occur and it becomes difficult to control the particle size, and the obtained core particles may contain coarse powder or irregular shapes.

  In addition, it is preferable that the electrolyte is mixed not intermittently but intermittently or continuously over a certain period of time. The mixing time varies depending on the amount used, but it is more preferable to mix for 0.5 minutes or more. Usually, when the electrolyte is mixed, abrupt aggregation starts as soon as the electrolyte is mixed. Therefore, a large amount of polymer primary particles, colorant particles, or aggregates left behind in the aggregation tend to remain. These are considered to be one of the sources of fine powder. According to the said operation, since uniform agglomeration can be performed without abrupt agglomeration, generation | occurrence | production of a fine powder can be prevented.

  Moreover, the final temperature of the aggregation step when the electrolyte is mixed to perform aggregation is preferably 20 ° C or higher, more preferably 30 ° C or higher, preferably 70 ° C or lower, more preferably 60 ° C or lower. Here, controlling the temperature before the aggregation step is one of the methods for controlling the particle diameter of the toner to a specific range of particle diameter according to the present invention. Some colorants added to the aggregating step induce aggregation, such as the electrolyte, and sometimes aggregate without adding electrolyte. This aggregation causes fine powder to be generated. Therefore, the aggregation can be prevented by cooling the temperature of the polymer primary particle dispersion in advance when mixing the colorant dispersion. In this production method, the polymer primary particles are cooled in advance in a range of preferably 0 ° C. or higher, more preferably 2 ° C. or higher, preferably 15 ° C. or lower, more preferably 12 ° C. or lower, and particularly preferably 10 ° C. or lower. It is good to keep. Note that this method is not effective only when the electrolyte is added and agglomerated, but the agglomeration is performed without mixing the electrolyte, such as a method of agglomeration by mixing a polar organic solvent such as pH control or alcohol. It is used also for the method of performing, and it is not limited to the aggregation method in particular.

  When the aggregation is performed by heating, the final temperature of the aggregation step is usually (Tg−20 ° C.) or higher, preferably (Tg−10 ° C.) or higher, when the polymer primary particle glass transition temperature is expressed as Tg. It is Tg or less, preferably (Tg-5 ° C.) or less.

  In addition, as a method for preventing sudden aggregation in order to prevent the generation of fine powder, there is a method of mixing demineralized water or the like. The method of mixing demineralized water or the like has a less cohesive action than the method of mixing the electrolyte, so it is not a method that is actively adopted in terms of production efficiency in the general manufacturing method. A large amount of filtrate tends to be obtained. However, it is very effective when fine aggregation control is required as in the present invention. Moreover, in this invention, it is preferable to employ | adopt combining combining the method of heating, the method of mixing electrolyte, etc. At this time, the method of mixing the desalted water after mixing the electrolyte is particularly preferable in that the aggregation is easily controlled.

  The time required for agglomeration is optimized by the shape of the apparatus and the processing scale. In order to reach the target particle size of the toner base particles, the temperature at which the aggregation process is completed, for example, the emulsifier The time from the temperature 8 ° C. lower than the temperature during the operation of stopping the growth of the core particles by mixing, pH control, etc. (hereinafter sometimes abbreviated as “aggregation final temperature”) to the aggregation final temperature is 30 minutes or more. Preferably, it is more preferably 1 hour or longer. The polymer primary particles, colorant particles, or aggregates thereof remaining by extending the time are not left behind, but are taken into the target core particles or agglomerate with each other so that the target core is obtained. Become particles.

  In order to obtain a toner that satisfies all the requirements (i) to (iii), it is preferable to employ an operation in which the aggregation speed is not high compared to the operation that is normally performed in the aggregation process. Examples of the operation in which the speed of aggregation is not high include, for example, cooling the dispersion to be used in advance, mixing the dispersion over time, employing an electrolyte that does not have a large aggregation action, There are methods such as intermittent mixing, slowing the rate of temperature rise, and lengthening the aggregation time.

In the aging step, it is preferable to employ an operation in which the aggregated particles are difficult to redisperse. Examples of operations in which the aggregated particles are difficult to finely disperse include, for example, a method of lowering the number of rotations of stirring, a method of mixing the dispersion stabilizer continuously or intermittently, a method of mixing the dispersion stabilizer and water in advance. is there.
In addition, the toner satisfying all the requirements (i) to (iii) is obtained by converting the finally obtained toner or toner base particles into particles having a volume median diameter (Dv50) or less by an operation such as classification. It is preferable to be obtained without going through the removing step.

(Shell coating process)
In this production method, toner primary particles are obtained by aggregating polymer primary particles to form core particles, and washing and drying the particles obtained by fusing after a shell coating step for fixing or adhering resin fine particles and the like. Is preferably obtained. In this case, since the obtained toner base particles have a resin coating layer, that is, the toner has a resin coating layer, there are obtained advantages that the stability, long-term storage stability and environmental resistance of the toner are improved. .

  The ratio of the resin fine particles to the whole core particles is usually 0.5 parts by weight or more, preferably 5 parts by weight or more, and usually 30 parts by weight or less, preferably 20 parts by weight or less with respect to 100 parts by weight of the core particles. .

  The resin fine particles may be produced by the same method as the polymer primary particles, and the configuration thereof is not particularly limited. However, the ratio of the total amount of polar monomers in 100% by mass of all polymerizable monomers constituting the binder resin as the resin fine particles is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and further Preferably it is 0.2 mass% or more, Preferably it is 3 mass% or less, More preferably, it is 1.5 mass% or less. When the amount is within the above range, the dispersion stability of the obtained resin fine particles is improved, and the particle shape and particle size can be easily adjusted in the aggregation step.

  Further, the proportion of the total amount of polar monomers in 100% by mass of the total polymerizable monomer constituting the binder resin as the resin fine particles is in 100% by mass of the total polymerizable monomer constituting the binder resin as the polymer primary particle. It is preferable that the ratio is smaller than the ratio of the total amount of polar monomers to be used because the particle shape and particle size can be easily adjusted in the aggregation process, the generation of fine powder can be suppressed, and the charging characteristics are excellent.

  In addition, the glass transition temperature of the binder resin as the resin fine particles is preferably higher than the glass transition temperature of the binder resin as the polymer primary particles from the viewpoint of storage stability and the like.

  In this production method, the toner base particles can be formed by coating (adhering or fixing) resin fine particles on the surface of the core particles as necessary. The volume average diameter (Mv) of the resin fine particles is preferably 0.02 μm or more, more preferably 0.05 μm or more, preferably 3 μm or less, more preferably 1.5 μm or less. In general, the use of the resin fine particles tends to promote the generation of fine powder that does not reach a predetermined toner particle size. Therefore, the conventional toner coated with resin fine particles tends to increase the amount of fine powder that does not satisfy a predetermined toner particle size.

  In this production method, when the amount of the wax is increased, the high temperature fixability is improved, but the wax is likely to be exposed on the toner surface, so that the chargeability and heat resistance may be deteriorated. However, the deterioration of performance can be prevented by coating the surface of the core particles with resin fine particles not containing wax.

  However, when the resin fine particles contain wax for the purpose of improving the high-temperature fixability, the resin fine particles once attached to the surface of the core particles are easily peeled off. This is presumably because the resin fine particles described above have a wide particle size distribution, so that there are large-sized resin fine particles with weak adhesion. Therefore, in order to reduce the peeling off, it is preferable to raise the temperature while mixing an aqueous solution in which a dispersion stabilizer and water are mixed in advance in a liquid in which particles having resin fine particles attached to the surface are dispersed. .

  In addition, when adopting the “step of starting the temperature rise after mixing the emulsifier” as described later, that is, when the aging step is performed after abruptly reducing the cohesive force, the cohesive force is rapidly reduced. In some cases, the fine resin particles once adhered may be easily detached. Therefore, it is preferable to fuse the resin fine particles after adhering them without significantly reducing the cohesive force and suppressing the particle diameter growth.

(Aging process)
In the emulsion polymerization aggregation method, in order to increase the stability of the particle aggregate obtained by aggregation, an emulsifier and a pH adjuster are mixed as a dispersion stabilizer to reduce the cohesive force between the particles and grow toner base particles. It is preferable to add an aging step for causing fusion between the agglomerated particles after stopping.

  The amount of the emulsifier to be mixed is not limited, but is preferably 0.1 parts by weight or more, more preferably 1 part by weight or more, still more preferably 3 parts by weight or more with respect to 100 parts by weight of the solid component of the mixed dispersion. Further, it is preferably 20 parts by weight or less, more preferably 15 parts by weight or less, and still more preferably 10 parts by weight or less. After the aggregation process, before the completion of the ripening process, by mixing an emulsifier or increasing the pH value of the flocculation liquid, aggregation of the particle aggregates aggregated in the aggregation process can be suppressed. The generation of coarse particles in the toner can be suppressed.

  Here, as a method of controlling the particle size within a specific range which means that the particle size distribution is sharp in the second toner according to the present invention, for example, the number of stirring rotations before the step of mixing the emulsifier and the pH adjuster is performed. A method of reducing the shearing force, that is, a method of reducing the shearing force by stirring. This method is preferably employed when a system having a weak aggregating action, for example, an emulsifier or a pH adjuster is mixed at a time and rapidly transferred to a stable (dispersed) system. As described above, if the method of raising the temperature while mixing an aqueous solution in which a dispersion stabilizer and water are mixed in advance is adopted, if the stirring rotational speed is decreased, the system is too inclined to agglomeration, so the particle size May lead to hypertrophy.

As an example, a toner having a specific particle size distribution used in the image forming apparatus of the present invention, that is, the second toner according to the present invention satisfying all the requirements (i) to (iii) can be obtained by the above method. it can. However, the content of the fine powder can be adjusted according to the degree of lowering the rotational speed, which will be further described. For example, when the stirring rotation speed is reduced from 250 rpm to 150 rpm, a toner having a smaller particle diameter with a sharper particle size distribution than that of a known toner can be provided, and the second toner according to the present invention can be obtained. However, this value is
(A) The diameter of the stirring vessel (as a so-called general cylindrical shape) and the maximum diameter of the stirring blade (and its relative ratio),
(B) The height of the stirring vessel,
(C) The peripheral speed at the tip of the stirring blade,
(D) The shape of the stirring blade,
(E) the position of the blade in the stirring vessel,
It depends on the conditions.
In particular, (c) is preferably 1.0 m / second or more, more preferably 1.2 m / second or more, particularly preferably 1.5 m / second, and preferably 2.5 m / second or less, and 2.3 m. / Second or less is more preferable, and 2.2 m / second or less is particularly preferable. This is because, within the above range, a suitable shear rate that does not peel off and does not enlarge is given to the particles.

The temperature of the ripening step is preferably Tg or higher, more preferably 5 ° C higher than Tg, and preferably 80 ° C higher than Tg, when the glass transition temperature Tg of the binder resin as the polymer primary particles is used. Below the temperature, more preferably below 50 ° C. above the Tg.
The time required for the aging step varies depending on the shape of the target toner, but after reaching the glass transition temperature of the polymer constituting the polymer primary particles, usually 0.1 hour or more, preferably 1 hour or more. In addition, it is usually desirable to hold for 5 hours or less, preferably 3 hours or less.

  By such a heat treatment, the polymer primary particles in the aggregate are fused and integrated, and the shape of the toner base particles as the aggregate becomes close to a sphere. The particle aggregate before the aging step is considered to be an aggregate due to electrostatic or physical aggregation of the polymer primary particles, but after the aging step, the polymer primary particles constituting the particle aggregate are fused to each other. In addition, the shape of the toner base particles can be made nearly spherical. According to such a ripening step, by controlling the temperature and time of the ripening step, the shape of the polymer primary particles is agglomerated, the potato type with advanced fusion, the spherical shape with further fusion For example, various shapes of toner can be manufactured according to the purpose.

(Washing / drying process)
The particle aggregate obtained through each of the above steps is subjected to solid / liquid separation according to a known method, the particle aggregate is recovered, then washed as necessary, and then dried. Toner mother particles can be obtained.

  Further, resin fine particles mainly composed of a polymer are further formed on the surface of the particles obtained by the emulsion polymerization aggregation method by a method such as a spray drying method, an in-situ method, or a submerged particle coating method. The outer layer is preferably formed with a thickness of 0.01 μm or more and 0.5 μm or less to provide encapsulated toner base particles.

(Other matters regarding the emulsion polymerization aggregation method)
By devising the manufacturing method as described above, toner base particles that can satisfy all the requirements (i) to (iii) can be manufactured. Although this toner base particle may be used as it is as the toner according to the present invention, usually, a toner satisfying all the requirements (i) to (iii) is obtained by performing an external addition process described later.

The toner of the present invention may be one in which a known external additive is blended on the surface of the toner base particles in order to control fluidity and developability (external addition treatment). Examples of the external additive include metal oxides and hydroxides such as alumina, silica, titania, zinc oxide, zirconium oxide, cerium oxide, talc, hydrotalcite, calcium titanate, strontium titanate, barium titanate, etc. Metal titanates, nitrides such as titanium nitride and silicon nitride, carbides such as titanium carbide and silicon carbide, and organic particles such as acrylic resins and melamine resins. In addition, an external additive may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. Among these, silica, titania, and alumina are preferable, and those that have been surface-treated with, for example, a silane coupling agent or silicone oil are more preferable. The average primary particle size is
Preferably it is 1 nm or more, More preferably, it is 5 nm or more, Preferably it is 500 nm or less, More preferably, it is 100 nm or less. It is also preferable to use a combination of a small particle size and a large particle size in the particle size range. The total amount of the external additive is preferably 0.05 parts by weight or more, more preferably 0.1 parts by weight or more, preferably 10 parts by weight or less, more preferably 100 parts by weight of the toner base particles. Is 5 parts by weight or less.

  The toner according to the present invention obtained by the emulsion polymerization aggregation method preferably has an average circularity measured using a flow particle image analyzer FPIA-2100 (manufactured by Sysmex Corporation (formerly Toa Medical Electronics)). It is 0.930 or more, More preferably, it is 0.940 or more, More preferably, it is 0.942 or more. It is considered that the closer to a sphere, the less the charge amount is localized in the particles, and the developability tends to be uniform. However, making a perfect spherical toner deteriorates the cleaning property, so the average circularity Is preferably 0.99 or less, more preferably 0.98 or less, and still more preferably 0.97 or less.

[Production method of toner by pulverization method]
The toner according to the present invention can also be produced, for example, by a pulverization method. In the pulverization method, a toner is manufactured by pulverizing a resin. In this case, since the particle size distribution of the toner obtained by the pulverization method (hereinafter referred to as “pulverized toner” as appropriate) is often not desired, the pulverized toner is usually classified.

  The resin used for producing the pulverized toner may be appropriately selected from those known to be usable for toner. For example, styrene resin, vinyl chloride resin, rosin modified maleic acid resin, phenol resin, epoxy resin, saturated or unsaturated polyester resin, ionomer resin, polyurethane resin, silicone resin, ketone resin, ethylene-acrylate copolymer, xylene Resin, polyvinyl butyral resin, etc. are used. Of these, polyester resins are preferred. In addition, these resin may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

The polyester resin is composed of a polyhydric alcohol and a polybasic acid, and if necessary, a polymerizable monomer composition containing at least one of these polyhydric alcohol and polybasic acid containing a trifunctional or higher polyfunctional component (crosslinking component). Obtained by polymerization.
In the above, among the polyhydric alcohols used for the synthesis of the polyester resin, examples of the divalent alcohol include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4. -Butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol and other diols, bisphenol A, hydrogenated bisphenol A, polyoxyethylenated bisphenol A, polyoxy Examples thereof include bisphenol A alkylene oxide adducts such as propylene bisphenol A and the like. Among these monomers, it is particularly preferable to use a bisphenol A alkylene oxide adduct as the main component monomer, and among them, an adduct having an average number of alkylene oxide additions per molecule of 2 to 7 is preferable.

Examples of the trihydric or higher polyhydric alcohol involved in the crosslinking of polyester include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripenta. Erythritol, sucrose, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane 1,3,5-trihydroxymethylbenzene, and the like.
In addition, a polyhydric alcohol may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  On the other hand, as the polybasic acid, for example, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, Mention may be made of divalent organic acids such as malonic acid, anhydrides of these acids, lower alkyl esters, alkenyl succinic acids such as n-dodecenyl succinic acid and n-dodecyl succinic acid, or alkyl succinic acids.

Examples of the tribasic or higher polybasic acid involved in the crosslinking of polyester include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and 1,2,4-cyclohexanetricarboxylic acid. 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra ( Methylene carboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, and anhydrides thereof.
In addition, a polybasic acid may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

These polyester resins can be synthesized by a usual method. For example, conditions such as reaction temperature (170 ° C. or higher and 250 ° C. or lower), reaction pressure (5 mmHg or higher and normal pressure or lower) are determined according to the reactivity of the monomer, and the reaction may be terminated when predetermined physical properties are obtained. .
The softening point of the polyester resin is preferably 90 ° C. or higher, more preferably 95 ° C. or higher, 135 ° C. or lower, more preferably 133 ° C. or lower. The range of the glass transition temperature is, for example, from 50 ° C. to 65 ° C. when the softening point is 90 ° C., and from 60 ° C. to 75 ° C. when the softening point is 135 ° C. In this case, if the softening point is lower than the above range, an offset phenomenon at the time of fixing tends to occur. If the softening point is higher than the above range, the fixing energy increases, and the color toner tends to deteriorate glossiness and transparency. Further, if the glass transition temperature is lower than the above range, toner agglomerates and sticking are likely to occur, and if it is higher than the above range, the fixing strength at the time of thermal fixing tends to decrease.

  The softening point of the polyester resin can be adjusted mainly by the molecular weight of the resin. When the tetrahydrofuran soluble content of the resin is measured by the GPC method, the number average molecular weight is preferably 2000 or more, more preferably 3000 or more, preferably 20000 or less, More preferably, it should be 12000 or less. The glass transition temperature can be adjusted mainly by selecting the monomer component constituting the resin. For example, the glass transition temperature can be increased by using an aromatic polybasic acid as a main component as the acid component. That is, among the polybasic acids described above, for example, phthalic acid, isophthalic acid, terephthalic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid and the like, anhydrides thereof, lower alkyl esters, etc. It is desirable to use as the main component.

Here, the softening point is defined as a value measured using a flow tester described in JIS K7210 and K6719. Specifically, using a flow tester (CFT-500, manufactured by Shimadzu Corporation), a plunger having an area of 1 cm ² while heating a sample of about 1 g at a preheating time of 50 ° C. for 5 minutes and a heating rate of 3 ° C./min. A load of 30 kg / cm ² is applied by pushing through a die having a hole diameter of 1 mm and a length of 10 mm. Thus, a plunger stroke-temperature curve is drawn, and when the height of the S-shaped curve is “h”, the temperature corresponding to “h / 2” is defined as the softening point. Moreover, the measurement of a glass transition temperature is defined as what was measured in accordance with the conventional method using the differential scanning calorimeter (DSC7 by Perkin-Elmer company, or DSC120 by Seiko Electronics Co., Ltd.).

  In general, when the acid value of the polyester resin is too high, it is difficult to obtain a stable high charge amount, and the charge stability at high temperature and high humidity tends to deteriorate. Therefore, the acid value of the polyester resin is preferably adjusted to 50 KOH mg / g or less, more preferably 30 KOH mg / g or less, and particularly preferably 15 KOH mg / g or less. The lower limit is usually 3 KOHmg / g or more.

  Examples of a method for adjusting the acid value of the polyester resin within the above range include, for example, a method of controlling the blending ratio of alcohol-based and acid-based monomers used at the time of resin synthesis, and a lower acid monomer component in advance by transesterification. Examples thereof include a method of synthesizing using an alkyl ester, a method of neutralizing residual acid groups by blending a basic component such as an amino group-containing glycol in the composition, and the like. However, these methods are merely examples, and any known method can be employed without being limited thereto. Here, the acid value of the polyester resin is measured according to the method of JIS K0070. However, when the resin is difficult to dissolve in the solvent, a good solvent such as dioxane is used.

The polyester resin is represented by the following formulas (a) to (d) when the glass transition temperature (Tg) is plotted as an x-axis variable and the softening point (Sp) is plotted as a y-axis variable on the xy coordinates. Those having physical properties within a range surrounded by a straight line are preferred. The unit of Tg and Sp is “° C.”.
Formula (a) Sp = 4 * Tg-110
Formula (b) Sp = 4 * Tg-170
Formula (c) Sp = 90
Formula (d) Sp = 135

  When a polyester resin having physical properties surrounded by straight lines represented by the formulas (a) to (d) is used for the pulverized toner, the pulverized toner has extremely high resistance to mechanical stress. In addition, the toner can be prevented from aggregating and solidifying due to frictional heat generated during continuous use, and appropriate chargeability can be maintained over a long period of time.

The pulverized toner may contain components other than the resin. For example, a colorant may be included. The colorant used in the pulverization method is not particularly limited as long as it is a commonly used colorant. For example, the colorant used for the above-described polymerized toner can be used.
The content ratio of the colorant may be an amount sufficient for the obtained toner to form a visible image by development. For example, the content is usually 1 part by mass or more, preferably 3 parts by mass with respect to 100 parts by mass of the resin. It is usually 25 parts by mass or less, preferably 15 parts by mass or less, more preferably 12 parts by mass or less.

The pulverized toner may contain, for example, a charge control agent. Any known charge control agent can be used. For example, examples of the charge control agent for positive charge include nigrosine dyes, amino group-containing vinyl copolymers, quaternary ammonium salt compounds, and polyamine resins. Examples of the charge control agent for negative charge include metal-containing azo dyes containing metals such as chromium, zinc, iron, cobalt, and aluminum, salts of salicylic acid or alkylsalicylic acid with the aforementioned metals, metal complexes, and the like. Can be mentioned. In addition, only 1 type may be used for a charge control agent and it may use 2 or more types together by arbitrary combinations and a ratio.
The amount of the charge control agent used is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, preferably 25 parts by mass or less, more preferably 15 parts by mass or less with respect to 100 parts by mass of the resin. is there. In this case, the charge control agent may be blended in the resin, or may be used in a form adhered to the surface of the toner base particles.

  Among these charge control agents, taking into account the ability to impart charge to the toner and color toner adaptability (the charge control agent itself is colorless or light and has no color disturbance to the toner), A group-containing vinyl copolymer and / or a quaternary ammonium salt compound is preferable, and for negative chargeability, metal salts and metal complexes of salicylic acid or alkylsalicylic acid with chromium, zinc, aluminum, boron and the like are preferable.

Among these, examples of the amino group-containing vinyl copolymer include copolymer resins of amino acrylates such as N, N-dimethylaminomethyl acrylate and N, N-diethylaminomethyl acrylate with styrene and methyl methacrylate. . Examples of the quaternary ammonium salt compound include tetraethylammonium chloride, a salt-forming compound of benzyltributylammonium chloride and naphtholsulfonic acid, and the like. For positively chargeable toners, the above amino group-containing vinyl copolymers and quaternary ammonium salt compounds may be blended alone or in combination.
As the metal salt and metal complex of salicylic acid or alkyl salicylic acid, among various known substances, chromium, zinc or boron complex of 3,5-ditertiary butyl salicylic acid is particularly preferable.

  The above colorant and charge control agent may be subjected to preliminary dispersion treatment, so-called master batch treatment, by pre-kneading with a resin in advance in order to improve dispersibility and compatibility in the toner.

  In the pulverized toner, any other known component such as a low molecular weight polyalkylene, a low melting point release agent such as a paraffin wax, an ester wax, or the like can be contained as other constituent components.

Examples of specific operations for producing the toner according to the present invention by a pulverization method include the following.
1. The resin and the charge control substance, colorant, and additive contained as necessary are uniformly dispersed by a dispersing device such as a Henschel mixer.
2. The obtained dispersion is melt-kneaded by a melt-kneader such as a kneader, an extruder, or a roll mill.
3. The obtained kneaded material is coarsely pulverized by a coarse pulverizer such as a hammer mill or a cutter mill, and then finely pulverized by a fine pulverizer such as a jet mill or an I-type mill.
4). The obtained finely pulverized product is classified by a classifier such as a dispersion classifier or a zigzag classifier.
5. In the obtained classified product, an external additive such as silica is dispersed with a Henschel mixer or the like, if necessary.

  In particular, the toner according to the present invention can be produced by the pulverization method by performing classification until the specific particle size distribution according to the present invention is obtained in the above-described operation 4.

(Suspension polymerization method)
A method for producing the toner according to the present invention by the suspension polymerization method is not particularly limited. And the like, the stirring strength during suspension polymerization, the mixing method of the polymerizable monomer, the types and amounts of the polymerization initiator and chain transfer agent, the polymerization temperature, and the degree of classification. . Particularly preferable methods include a method in which a high shearing force is applied in a process in which polymerizable monomer droplets are generated, or a dispersion stabilizer or the like is increased.

  Examples of the raw material such as resin used when producing the toner according to the present invention by the suspension polymerization method include those described in the section of the emulsion polymerization aggregation method.

[Chemical grinding method typified by melt suspension method]
A method for producing the toner according to the present invention by a chemical pulverization method typified by a melt suspension method is not particularly limited. For example, the type of binder polymer, chemical structure, molecular weight distribution, etc .; It is carried out by adjusting the type and amount of the additive in water; stirring intensity at the time of mixing the polymer solution, mixing method, temperature, etc .;

  Examples of the resin used when the toner is manufactured by a chemical pulverization method such as a melt suspension method include those described in the section of the pulverization method. Other materials include those described in the emulsion polymerization aggregation method.

[4. Image forming apparatus]
An embodiment of an image forming apparatus using an electrophotographic photosensitive member according to 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, an image forming apparatus according to the present invention includes an electrophotographic photosensitive member 1, a charging device 2 as a charging unit, an exposure device 3 as an image exposure unit, and a developing device 4 as a developing unit (with toner T inside). And a transfer device 5 as transfer means, and a cleaning device 6 and a fixing device 7 are provided as necessary.

  The electrophotographic photosensitive member 1 is not particularly limited as long as it is the above-described photosensitive member of the present invention, but in FIG. 1, as an example, a drum-shaped member 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.

  The charging device 2 is optional as long as it can charge the electrophotographic photoreceptor 1. Specific examples of the charging device 2 include a corona charging device such as a corotron and a scorotron, a direct charging device (contact type charging device) that makes a direct charging member applied with a voltage come into contact with the surface of the photosensitive member, and the like. It is done. Examples of the direct charging member (contact charger) include a charging roller and a charging brush.

  As the direct charging means by the direct charging device, there are a contact charging means with air discharge and an injection charging means without air discharge, and any method can be applied in the present invention.

  Moreover, as a voltage applied at the time of charging, it is possible to use only a direct current voltage or to superimpose alternating current on direct current. In FIG. 1, a roller-type charging device (charging roller) is shown as an example of the charging device 2.

  The exposure device 3 is not limited in the number, type, etc. as long as it can expose the charged electrophotographic photoreceptor 1 to form an electrostatic latent image on the photosensitive surface of the electrophotographic photoreceptor 1. . Therefore, the number of exposure apparatuses may be one, or two or more. Specific examples of the exposure apparatus 3 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. However, in the image forming apparatus of the present invention, the wavelength of light for exposure is usually 380 nm or more, and usually 500 nm or less, preferably 480 nm or less, more preferably 430 nm or less, and monochromatic light having a short wavelength is used. To do. The photoconductor of the present invention exhibits excellent effects peculiar to the present invention by combining with such blue (purple) monochromatic light.

  As long as the developing device 4 has toner T and develops the formed electrostatic latent image with toner T, the type thereof is not limited, and cascade development, one-component conductive toner development, and two-component magnetic brush development. An arbitrary apparatus such as a dry development system such as a wet development system or the like can be used. 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. This 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 fluororesin, 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 a silicone resin or a urethane resin, a metal blade such as stainless steel, aluminum, copper, brass, phosphor bronze, or a blade obtained by coating such a metal blade with a 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 weight / 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 T, it is preferable to use the toner in the present invention described above. As an example, FIG. 1 shows a toner storage form, but the storage method, storage location, replenishment method, and the like are arbitrary as long as the effects of the present invention are not significantly limited.

  The type of the transfer device 5 is not 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 T to a recording paper (paper, medium, transfer target). As a result, the toner image F formed on the electrophotographic photosensitive member 1 can be transferred onto the recording paper (paper, medium, transfer target) P.

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

  The fixing device 7 includes an upper fixing member (pressure 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, a fixing sheet, or the like. 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 an arbitrary method such as heat roller fixing, flash fixing, oven fixing, pressure fixing, or the like can be provided.

  In the electrophotographic apparatus configured as described above, an image is recorded by the following method.

  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.

  A cartridge having the electrophotographic photosensitive member 1 (this is appropriately referred to as an “electrophotographic cartridge”) is configured to be detachable from a main body of an image forming apparatus such as a copying machine or a laser beam printer. May be.

  Further, the electrophotographic cartridge may be combined with one or more elements of the toner T, 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. . In this case, an electrophotographic cartridge can be obtained by using a cartridge case configured to be detachable with respect to the image forming apparatus and accommodating and supporting the cartridge case in combination with the above-described elements.

  With this configuration, for example, when the electrophotographic photosensitive member 1 or other member deteriorates, the electrophotographic cartridge can be removed from the image forming apparatus main body, and another new electrophotographic cartridge can be attached to the image forming apparatus main body. .

  Also, when the toner T runs out of the toner cartridge, the toner cartridge may be taken out from the image forming apparatus main body and easily filled with toner, or another new toner cartridge may be mounted. it can. Accordingly, maintenance and management of the image forming apparatus are facilitated.

  The toner T used in the electrophotographic cartridge of the present invention preferably has an average circularity measured by a flow type particle image analyzer of 0.940 or more and 1.000 or less.

Further, as the toner T used in the electrophotographic cartridge of the present invention, it is also preferable to use a toner that satisfies all of the following (i) to (iii).
(I) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 μm or less.
(Ii) The average circularity is 0.93 or more.
(Iii) The relationship between the volume median diameter (Dv50) of the toner and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50). Fulfill.

[5. Advantages of Image Forming Apparatus of Present Invention]
The electrophotographic photoreceptor of the present invention has a low residual potential when an image is formed with monochromatic light having a wavelength of 380 nm to 500 nm, and usually has a high spectral sensitivity and excellent electrical characteristics. Further, by using an exposure light source having a wavelength of 380 nm to 500 nm, the beam spot diameter on the electrophotographic photosensitive member can be reduced, and a high resolution image can be obtained.

  The image forming apparatus of the present invention can form an image with high quality represented by high resolution, high gradation, and the like, and with few defects developed faithfully for high resolution exposure.

  The reason for the above advantages is not clearly understood. However, according to the inventor's guess, it is considered that a suitable latent image was obtained by combining the photoconductor of the present invention with short wavelength monochromatic light. Further, the toner is developed with a toner having high compatibility with the latent image, and it is considered that a more excellent effect is obtained.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. The present invention is not limited to the following examples, and can be implemented with appropriate modifications without departing from the gist thereof. In the following, “part” means “part by weight”.

[Calculation method of viscosity average molecular weight]
The viscosity average molecular weight of the binder resin contained in the charge transport layer was calculated as follows.
The binder resin was dissolved in dichloromethane to prepare a solution having a concentration C of 6.00 [g / L]. The flow time t [s] of the sample solution was measured in a constant temperature water bath set to 20.0 ° C. using an Ubbelohde capillary viscometer with a flow time t ₀ [s] of the solvent (dichloromethane) of 136.16 seconds. . And the viscosity average molecular weight Mv was computed according to the following formula | equation.
a = 0.438 × η _sp +1
η _sp = (t / t ₀ ) −1
t ₀ = 136.16 [s]
b = 100 × η _sp / C
C = 6.00 [g / L]
η = b / a
Mv = 3207 × η ^1.205

[Production Examples and Comparative Production Examples]
Hereinafter, the method for producing the charge generating material used in the examples and comparative examples of the present invention will be described in detail.

<Production Example 1>
3,8.8 g of 3,6-dihydroxynaphthalic anhydride and 14.1 g of o-phenylenediamine were suspended in a mixed solvent of 86 mL of glacial acetic acid and 430 mL of nitrobenzene, and reacted for 8 hours while heating under reflux. After the reaction, the solid was collected by filtration, washed with 520 mL of methanol, and dried to obtain 36.3 g of a yellow solid.

1.6 g of the obtained yellow solid was dissolved in 245 mL of dimethyl sulfoxide, and 2,5-bis (p-aminophenyl) -1,3,4-oxa was added to the resulting solution at room temperature (20 ° C.). A solution of 1.1 g of diazole tetrazonium borofluoride dissolved in 15 mL of dimethyl sulfoxide was added dropwise. Next, a solution obtained by dissolving 2.3 g of sodium acetate in 7 mL of water was dropped, and the mixture was stirred for 3 hours to perform a coupling reaction. The precipitated solid was collected by filtration, washed successively with a 10% by weight acetic acid aqueous solution, water, and tetrahydrofuran (THF) and then dried to obtain 1.8 g of a composition. The resulting composition was a mixture of bisazo compounds represented by the following formula (T1).

<Production Example 2>
In place of o-phenylenediamine used in Production Example 1, 16.0 g of 3,4-diaminotoluene was used, and 38.4 g of a yellow solid was obtained in the same manner as in Production Example 1. A coupling reaction was performed in the same manner as in Production Example 1 except that 1.7 g of this yellow solid was used as a coupler to obtain 1.9 g of a composition. The resulting composition was a mixture of bisazo compounds represented by the following formula (T2).

<Production Example 3>
In the same manner as in Production Example 1, 9.1 g of a yellow solid obtained by reacting 3,6-dihydroxynaphthalic anhydride and o-phenylenediamine was suspended in 396 mL of N, N-dimethylformamide (DMF). 29.0 g of potassium carbonate and 5.7 g of tosyl chloride were added. After stirring at 80 ° C. for 2 hours, 12.4 g of potassium carbonate and 16.7 g of butyl iodide (n) were added, and the mixture was further stirred for 2 hours. The reaction solution was filtered while hot and then recrystallized using DMF and water to obtain 9.5 g of a yellow solid. This yellow solid was suspended in 333 mL of ethanol, heated to reflux, and 333 mL of a 1N aqueous potassium hydroxide solution was added dropwise. After stirring for 4.5 hours, the temperature was lowered, neutralized with acetic acid, and the precipitated solid was collected by filtration. This was washed with methanol to obtain 5.8 g of a yellow solid. 1.9 g of this yellow solid was dissolved in 290 mL of dimethyl sulfoxide and a coupling reaction was carried out in the same manner as in Production Example 1 except that it was used as a coupler to obtain 2.0 g of a composition. The resulting composition was a mixture of bisazo compounds represented by the following formula (T3).

<Production Example 4>
A coupler was synthesized in the same manner as in Production Example 3 except that 12.3 g of 1-bromo-2-methylpropane was used instead of butyl iodide (n) in Production Example 3, and a coupling reaction was performed. 1.8 g of product was obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T4).

<Production Example 5>
In the same manner as in Production Example 2, 11.4 g of a yellow solid obtained by reacting 3,6-dihydroxynaphthalic anhydride and 3,4-diaminotoluene was suspended in 490 mL of DMF, and 34.8 g of potassium carbonate was obtained. 6.9 g of tosyl chloride was added. After stirring at 80 ° C. for 2 hours, the temperature was lowered to 30 ° C., 24.8 g of potassium carbonate and 25.5 g of methyl iodide were added, and the mixture was further stirred at 20 ° C. or more and 35 ° C. or less for 2 hours. The reaction solution was heated to 80 ° C. and filtered while heating at 80 ° C., and the filtrate was recrystallized using DMF and water to obtain 20.3 g of a yellow solid. This yellow solid was suspended in 375 mL of ethanol, heated to reflux, and 375 mL of a 1N aqueous potassium hydroxide solution was added dropwise. Thereafter, the same treatment as in Production Example 3 was performed to obtain 7.3 g of a yellow solid. A coupling reaction was carried out in the same manner as in Production Example 1 except that 1.8 g of this yellow solid was dissolved in 267 mL of dimethyl sulfoxide and used as a coupler to obtain 1.9 g of a composition. The resulting composition was a mixture of bisazo compounds represented by the following formula (T5).

<Production Example 6>
A coupler was synthesized in the same manner as in Production Example 3 except that 15.9 g of bromomethylcyclohexane was used instead of butyl iodide (n) in Production Example 3, and 2.2 g of this coupler was dissolved in 580 mL of dimethyl sulfoxide. A coupling reaction was carried out in the same manner as in Example 1 except that it was used to obtain 1.9 g of a composition. The resulting composition was a mixture of bisazo compounds represented by the following formula (T6).

<Production Example 7>
Using the coupler produced in Production Example 4, instead of the tetrazonium borofluoride salt of 2,5-bis (p-aminophenyl) -1,3,4-oxadiazole of Production Example 1, 2- The coupling reaction was carried out in the same manner as in Production Example 1 except that 1.1 g of (m-aminophenyl) -5- (p-aminophenyl) 1,3,4-oxadiazole tetrazonium borofluoride was used. As a result, 1.6 g of the composition was obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T7).
(In formula (T7), Cp ₁₃ and Cp ₁₄ are the same as Cp ₇ and Cp ₈ in formula (T4) in Production Example 4, respectively).

<Production Example 8>
Coupling in the same manner as in Example 1 except that 1.8 g of the coupler produced in Production Example 6 and 0.9 g of 2-hydroxy-11H-benz (a) carbazole-3-carboxyanilide were dissolved in 540 mL of dimethyl sulfoxide. Reaction was performed and 1.1g of compositions were obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T8).

<Production Example 9>
A coupler was synthesized in the same manner as in Production Example 3 except that 13.7 g of 1-bromopentane (n) was used instead of butyl iodide (n) in Production Example 3, and 1.9 g of this coupler and 2-hydroxy- 11H-Benz (a) Carbazole-3-carboxy- (4-trifluoromethyl) anilide 1.1 g was used after dissolving in 291 mL of dimethyl sulfoxide and a coupling reaction was carried out in the same manner as in Example 1 to obtain a composition. 1.1 g was obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T9).

<Production Example 10>
A coupler was synthesized in the same manner as in Production Example 3 except that 15.4 g of benzyl bromide was used instead of butyl iodide (n) in Production Example 3, and 2.0 g of this coupler and 3′-cyclohexylmethyloxy-3 were synthesized. A coupling reaction was carried out in the same manner as in Example 1 except that 0.9 and g of hydroxy-2-naphthanilide was dissolved in 350 mL of dimethyl sulfoxide, and 1.9 g of a composition was obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T10).
(In formula (T10), Cp ₁₉ and Cp ₂₀ each independently represent one or more structures selected from the structural groups described below.

<Production Example 11>
Instead of o-phenylenediamine used in Production Example 1, 16.4 g of 4-fluorophenylenediamine was used, and 34.2 g of a yellow solid was obtained in the same manner as in Production Example 1. 6.5 g of the coupler was synthesized by reacting 11.5 g of this yellow solid with methyl iodide in the same manner as in Production Example 5, and 1.7 g of this coupler and 3′-cyclohexylmethyloxy-3-hydroxy-2-naphthanilide 0 A coupling reaction was carried out in the same manner as in Example 1 except that 9 g was dissolved in 261 ml of dimethyl sulfoxide to obtain 1.6 g of a composition. The resulting composition was a mixture of bisazo compounds represented by the following formula (T11).

<Production Example 12>
A coupling reaction was carried out in the same manner as in Example 1 except that 1.7 g of the coupler produced in Production Example 5 and 0.7 g of 3-hydroxy-2-naphthanilide (naphthol AS) were dissolved in 231 mL of dimethyl sulfoxide. 1.3 g of composition was obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T12).

<Production Example 13>
A coupling reaction was carried out in the same manner as in Example 1 except that 1.8 g of the coupler produced in Production Example 3 and 0.8 g of 3′-isobutoxy-3-hydroxy-2-naphthanilide were dissolved in 260 mL of dimethyl sulfoxide. 1.4 g of a composition was obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T13).

<Comparative Production Example 1>
A coupler was synthesized in the same manner as in Production Example 1 using 26.8 g of 3-hydroxynaphthalic anhydride instead of 3,6-dihydroxynaphthalic anhydride of Production Example 1, and 1.6 g of this coupler was synthesized. A coupling reaction was carried out in the same manner as in Production Example 1 except that 1.9 g of the composition was obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T14).

<Comparative Production Example 2>
A coupler was synthesized in the same manner as in Production Example 1 using 26.8 g of 3-hydroxynaphthalic anhydride instead of 3,6-dihydroxynaphthalic anhydride of Production Example 1, and the coupling reaction was performed. Instead of tetrazonium borofluoride of 2,5-bis (p-aminophenyl) -1,3,4-oxadiazole, 2- (m-aminophenyl) -5- (p-amino A coupling reaction was carried out in the same manner as in Production Example 1 except that 1.1 g of phenyl) -1,3,4-oxadiazole tetrazonium borofluoride was used to obtain 1.8 g of a composition. The resulting composition was a mixture of bisazo compounds represented by the following formula (T15).

<Comparative Production Example 3>
A coupling reaction was carried out in the same manner as in Production Example 8 except that 1.4 g of the coupler produced in Comparative Production Example 1 was used, thereby obtaining 1.3 g of a composition. The resulting composition was a mixture of bisazo compounds represented by the following formula (T16).

<Comparative Production Example 4>
The coupling reaction was carried out in the same manner as in Production Example 12 except that 1.4 g of the coupler produced in Comparative Production Example 1 and 0.7 g of 3-hydroxy-2-naphthanilide (naphthol AS) were dissolved in 210 mL of dimethyl sulfoxide. As a result, 1.4 g of the composition was obtained. The resulting composition was a mixture of bisazo compounds represented by the following formula (T17).

[Production of Electrophotographic Photoreceptor Containing Compound of the Present Invention and Analogous Compounds]
Examples relating to a photoreceptor using the compound of the present invention as a charge generating material will be described below with reference to Examples 1 to 13. In addition, Comparative Examples 1 to 4 are used for comparison with the case where a charge generating material having a structure similar to the compound of the present invention is used.

<Example 1>
・ Preparation of charge generation layer coating solution
0.75 part of polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name “Denkabutyral” # 6000C) and 0.75 part of phenoxy resin (manufactured by Union Carbide, PKHH) A binder solution was prepared by dissolving in 5 parts.

  Subsequently, 30 parts of 1,2-dimethoxyethane was added to 1.5 parts of the composition produced in Production Example 1, and the mixture was pulverized with a sand grind mill for 8 hours for atomization dispersion and mixed with the binder solution. .

  To the binder solution was further mixed 13.5 parts of a 9: 1 mixture of 1,2-dimethoxyethane and 4-methoxy-4-methyl-2-pentanone. By the above procedure, a charge generation layer coating solution having a solid content concentration of 4.0% by weight was prepared.

・ Preparation of charge transport layer coating solution
35 parts of a compound represented by the following formula (T18), 35 parts of a compound represented by the following formula (T19), and a polycarbonate resin represented by the following formula (T20) (m: n = 51: 49, viscosity average) A charge transport layer coating solution was prepared by dissolving 100 parts of a molecular weight of 30,000) in 480 parts of tetrahydrofuran and 120 parts of toluene.

-Production of a forward laminated type electrophotographic photosensitive member An aluminum film deposited on a 75 μm thick polyester film was used as a support. On top of this, the above charge generation layer coating solution was coated with a wire bar so that the film thickness after drying was 0.4 μm. This was air-dried to form a charge generation layer.

  On the charge generation layer, the above charge transport layer coating solution is applied with an applicator and dried at room temperature (25 ° C.) for 30 minutes and then at 125 ° C. for 20 minutes to form a charge transport layer having a thickness of 25 μm. A photoreceptor E1 was obtained.

・ Measurement of transmittance at desired wavelength of charge transport layer Apply the charge transport layer coating solution (charge transport layer coating solution used to produce the photoreceptor E1) used on this quartz glass with an applicator. The sample was dried at room temperature (25 ° C.) for 30 minutes and then at 125 ° C. for 20 minutes to form a sample of a charge transport layer having a thickness of 25 μm.

  In order to measure the transmittance of the sample of the charge transport layer with respect to light having a wavelength of 405 nm, measurement was performed using a spectrophotometer UV1650PC manufactured by Shimadzu Corporation with an equivalent quartz glass as a background. As a result of the measurement, the transmittance was 99.9%.

<Example 2>
In Example 1, a photoconductor E2 was produced in the same manner as in Example 1 except that the composition produced in Production Example 2 was used instead of using the composition produced in Production Example 1.

<Example 3>
In Example 1, a photoconductor E3 was produced in the same manner as in Example 1 except that the composition produced in Production Example 3 was used instead of the composition produced in Production Example 1.

<Example 4>
In Example 1, a photoconductor E4 was produced in the same manner as in Example 1 except that the composition produced in Production Example 4 was used instead of the composition produced in Production Example 1.

<Example 5>
In Example 1, a photoconductor E5 was produced in the same manner as in Example 1 except that the composition produced in Production Example 5 was used instead of the composition produced in Production Example 1.

<Example 6>
In Example 1, a photoconductor E6 was produced in the same manner as in Example 1, except that the composition produced in Production Example 6 was used instead of the composition produced in Production Example 1.

<Example 7>
In Example 1, a photoconductor E7 was produced in the same manner as in Example 1 except that the composition produced in Production Example 7 was used instead of using the composition produced in Production Example 1.

<Example 8>
In Example 1, a photoconductor E8 was produced in the same manner as in Example 1 except that the composition produced in Production Example 8 was used instead of the composition produced in Production Example 1.

<Example 9>
In Example 1, a photoconductor E9 was produced in the same manner as in Example 1 except that the composition produced in Production Example 9 was used instead of the composition produced in Production Example 1.

<Example 10>
In Example 1, a photoconductor E10 was produced in the same manner as in Example 1 except that the composition produced in Production Example 10 was used instead of the composition produced in Production Example 1.

<Example 11>
In Example 1, instead of using the composition produced in Production Example 1, Photoreceptor E11 was produced in the same manner as Example 1 except that the composition produced in Production Example 11 was used.

<Example 12>
In Example 1, a photoconductor E12 was produced in the same manner as in Example 1 except that the composition produced in Production Example 12 was used instead of the composition produced in Production Example 1.

<Example 13>
In Example 1, a photoconductor E13 was produced in the same manner as in Example 1 except that the composition produced in Production Example 13 was used instead of the composition produced in Production Example 1.

<Comparative Example 1>
In Example 1, a photoconductor P1 was produced in the same manner as in Example 1 except that the composition produced in Comparative Production Example 1 was used instead of using the composition produced in Production Example 1. .

<Comparative Example 2>
In Example 1, instead of using the composition produced in Production Example 1, a photoconductor P2 was produced in the same manner as in Example 1 except that the composition produced in Comparative Production Example 2 was used. .

<Comparative Example 3>
In Example 1, a photoreceptor P3 was produced in the same manner as in Example 1 except that the composition produced in Comparative Production Example 3 was used instead of using the composition produced in Production Example 1. .

<Comparative Example 4>
In Example 1, a photoconductor P4 was produced in the same manner as in Example 1 except that the composition produced in Comparative Production Example 4 was used instead of the composition produced in Production Example 1. .

<Example 14>
-Preparation of undercoat layer Rutile-type titanium oxide having an average primary particle size of 40 nm ("TTO55N" manufactured by Ishihara Sangyo) and 3% by weight of methyldimethoxysilane ("TSL8117" manufactured by Toshiba Silicone) based on the titanium oxide, The surface-treated titanium oxide was obtained by mixing with a Henschel mixer. Kogyo Kogyo Co., Ltd. having a mill volume of about 0.15 L, using 1 kg of a raw material slurry obtained by mixing 50 parts of the surface-treated titanium oxide and 120 parts of methanol, using zirconia beads having a diameter of about 100 μm (YTZ manufactured by Nikkato) as a dispersion medium. Using an ultra apex mill (UAM-015 type) manufactured by Co., Ltd., dispersion treatment was performed for 1 hour in a liquid circulation state with a rotor peripheral speed of 10 m / second and a liquid flow rate of 10 kg / hour to prepare a titanium oxide dispersion.

  This titanium oxide dispersion, a mixed solvent of methanol / 1-propanol / toluene, and ε-caprolactam [compound represented by the following formula (A)] / bis (described in the examples of JP-A-4-31870) 4-amino-3-methylcyclohexyl) methane [compound represented by the following formula (B)] / hexamethylenediamine [compound represented by the following formula (C)] / decamethylene dicarboxylic acid [represented by the following formula (D) Compound] / octadecamethylenedicarboxylic acid [compound represented by the following formula (E)] is heated with a copolyamide pellet having a composition molar ratio of 60% / 15% / 5% / 15% / 5%. While stirring, the polyamide pellets were dissolved by mixing.

  Thereafter, ultrasonic dispersion treatment with an ultrasonic transmitter having an output of 1200 W was performed for 1 hour, and further filtered through a polytetrafluoroethylene (PTFE) membrane filter (Advantech Mytex LC) having a pore diameter of 5 μm.

  According to the above procedure, the surface-treated titanium oxide / copolymerized polyamide has a weight ratio of 3/1, a mixed solvent of methanol / 1-propanol / toluene has a weight ratio of 7/1/2, and contains solid content. A dispersion A for forming an undercoat layer of 18.0 wt% was obtained.

  This undercoat layer forming dispersion A is dip-coated on an anodized aluminum cylinder (outer diameter 30 mm, length 375.8 mm, thickness 0.75 mm), and the film thickness after drying is 1.5 μm. An undercoat layer was provided so as to be.

Preparation of charge generation layer 0.75 part of polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name “Denkabutyral” # 6000C) and 0.75 part of phenoxy resin (manufactured by Union Carbide, PKHH) were added to 1,2-dimethoxyethane 28 A binder solution was prepared by dissolving in 5 parts.

  Subsequently, 30 parts of 1,2-dimethoxyethane was added to 1.5 parts of the composition produced in Production Example 2, and the mixture was pulverized and dispersed in a sand grind mill for 8 hours, and mixed with the binder liquid. did. Further, 13.5 parts of a 9: 1 (weight ratio) mixed solution of 1,2-dimethoxyethane and 4-methoxy-4-methyl-2-pentanone was mixed with the binder solution. By the above procedure, a charge generation layer coating solution having a solid content concentration of 4.0% by weight was prepared.

Using this charge generation layer coating solution, a charge generation layer was produced on the undercoat layer so that the film thickness after drying was 0.3 μm (0.3 g / m ² ).

Preparation of charge transport layer 35 parts of the compound represented by the formula (T18), 35 parts of the compound represented by the formula (T19), 8 parts of an antioxidant having the structure of the following formula (T21), and a leveling agent 0.05 parts of silicone oil (KF96 manufactured by Shin-Etsu Chemical Co., Ltd.), 100 parts of polycarbonate resin (m: n = 51: 49, viscosity average molecular weight 30,000) represented by the above formula (T20), 480 parts of tetrahydrofuran and toluene A charge transport layer coating solution was prepared by dissolving in 120 parts.

  On the charge generation layer, a charge transport layer coating solution was applied by dip coating so that the film thickness after drying was 18 μm, to obtain a photoreceptor drum E14 having a laminated photosensitive layer.

<Example 15>
In Example 14, a photoconductor E15 was produced in the same manner as in Example 14, except that the composition produced in Production Example 3 was used instead of the composition produced in Production Example 2.

<Example 16>
In Example 14, a photoconductor E16 was produced in the same manner as in Example 14 except that the composition produced in Production Example 5 was used instead of the composition produced in Production Example 2.

<Example 17>
In Example 14, a photoconductor E17 was produced in the same manner as in Example 14, except that the composition produced in Production Example 7 was used instead of the composition produced in Production Example 2.

<Example 18>
In Example 14, a photoconductor E18 was produced in the same manner as in Example 14, except that the composition produced in Production Example 8 was used instead of the composition produced in Production Example 2.

<Example 19>
In Example 14, a photoconductor E19 was produced in the same manner as in Example 14, except that the composition produced in Production Example 9 was used instead of the composition produced in Production Example 2.

<Example 20>
In Example 14, a photoconductor E20 was produced in the same manner as in Example 14, except that the composition produced in Production Example 10 was used instead of the composition produced in Production Example 2.

<Example 21>
In Example 14, a photoreceptor E21 was produced in the same manner as in Example 14 except that the composition produced in Production Example 13 was used instead of the composition produced in Production Example 2.

<Example 22>
The following charge transport layer coating solution was used in place of the charge transport layer coating solution used in Example 14, and the composition produced in Production Example 3 was used instead of the composition produced in Production Example 2. Produced a photoreceptor E22 in the same manner as in Example 14. Further, a charge transport layer sample was prepared by the same method as in Example 1 using the following charge transport layer coating solution, and the transmittance for light having a wavelength of 480 nm was measured. As a result, it was 98.0%.

Charge transport layer coating solution 10 parts of a compound represented by the following formula (T22), 60 parts of a compound represented by the following formula (T23), and a polycarbonate resin (viscosity average molecular weight of 40 represented by the following formula (T24)) , 000) 50 parts, polyarylate resin 25 parts (viscosity average molecular weight 45,000) represented by the following formula (T25), and polycarbonate resin (m: n = 9: 1) represented by the following formula (T26). , 25 parts of a viscosity average molecular weight 35,000) was dissolved in 480 parts of tetrahydrofuran and 120 parts of toluene to prepare a charge transport layer coating solution.

<Comparative Example 5>
In Example 14, a photoconductor P5 was produced in the same manner as in Example 14 except that the composition produced in Comparative Production Example 1 was used instead of using the composition produced in Production Example 2. .

<Comparative Example 6>
In Example 14, a photoconductor P6 was produced in the same manner as in Example 14 except that the composition produced in Comparative Production Example 2 was used instead of using the composition produced in Production Example 2. .

<Comparative Example 7>
In Example 14, a photoconductor P7 was produced in the same manner as in Example 14, except that the composition produced in Comparative Production Example 3 was used instead of using the composition produced in Production Example 2. .

<Comparative Example 8>
In Example 14, a photoconductor P8 was produced in the same manner as in Example 14 except that the composition produced in Comparative Production Example 4 was used instead of using the composition produced in Production Example 2. .

<Comparative Example 9>
In Example 22, a photoconductor P9 was produced in the same manner as in Example 22 except that the composition produced in Comparative Production Example 1 was used instead of using the composition produced in Production Example 3. .

[Comparison evaluation of produced electrophotographic photoreceptors]
<Electrical property evaluation 1>
Each photoconductor (see Table 4) obtained in each Example and Comparative Example is mounted on a photoconductor characteristic evaluation apparatus (Mitsubishi Chemical), and evaluation of electric characteristics by a cycle of charging, exposure, potential measurement, and static elimination. Went.

  Each photoconductor was wound around an aluminum drum having an outer diameter of 80 mm, and the aluminum drum and the aluminum vapor deposition layer of the photoconductor were electrically connected to each other and rotated at a constant rotation speed of 30 rpm. In an environment with a temperature of 25 ° C. and a humidity of 50%, the photosensitive member is charged so that the initial surface potential is −700 V, and the light from the halogen lamp is converted into a monochromatic light with a wavelength of 405 nm by using an interference filter and exposed. The charge removal light had an exposure width of 5 mm and white light of 75 lux was used to measure the residual potential (hereinafter referred to as “Vr” as appropriate) [V] after the charge removal light irradiation.

  These measurement results are shown in Table 5. Note that Vr is a potential after exposure, and a smaller value is excellent in electrical characteristics.

Further, these photoconductors were subjected to a 1-mm square 100-cut cross-cut test in accordance with JIS K5400 to evaluate the adhesive strength of the photoconductors. The results were evaluated in four stages from 0 (bad) to 3 (good). The results obtained are shown in Table 5.

  The photoreceptors of Examples 1 to 6 are compared to the photoreceptor of Comparative Example 1, the photoreceptor of Example 7 is compared to the photoreceptor of Comparative Example 2, and the photoreceptors of Examples 8 to 13 are Comparative Examples. Compared to the photoconductors 3 and 4, each had a good residual potential (Vr) and was a suitable photoconductor. Further, in terms of adhesive strength, the photoconductors of Examples 1 to 13 all had better adhesive strength than the photoconductors of Comparative Examples 1 to 4.

  The photoconductors of Examples 1 to 13 are practical photoconductors having a low residual potential, good electrical characteristics, high adhesive strength, and no photoconductor damage to monochromatic light having a wavelength of 405 nm, and image formation. The photoconductor was more suitable for the apparatus.

<Electrical property evaluation 2>
For the photoreceptors obtained in Examples 14 to 22 and Comparative Examples 5 to 9, except that the light from the halogen lamp was changed to a monochromatic light having a wavelength of 480 nm using an interference filter as the light source, Vr was measured in the same manner as in <Electrical Property Evaluation 1>.

These measurement results are shown in Table 6 (wavelength 480 nm). Note that the smaller the value of Vr, the better the electrical characteristics.

  The photoreceptors of Examples 14 to 16 are compared with the photoreceptor of Comparative Example 5, the photoreceptor of Example 17 is compared to the photoreceptor of Comparative Example 6, and the photoreceptors of Examples 18 to 21 are Comparative Examples. Compared to the photoconductors of No. 7 and Comparative Example 8, the photoconductor of Example 22 is a favorable photoconductor with a lower Vr and better than the photoconductor of Comparative Example 9, and particularly a wavelength of 480 nm. It was very suitable for use in an image forming apparatus for exposure. Further, the photoconductor of Example 22 in which the kind of the charge transport material was changed was also a photoconductor suitable for use.

  The photoreceptor containing the specific azo compound of the present invention in the photosensitive layer showed an excellent residual potential value even when blue (purple) light was used as the exposure light. Since conventional photoconductors cannot use blue light as exposure light, image forming apparatuses using conventional photoconductors produce images with high resolution and high gradation and images with few defects. At the same time, the high quality image achieved could not be formed. Therefore, according to the image forming apparatus using the photoconductor of the present invention, an image having high quality represented by high resolution and high gradation and having few defects developed faithfully for high resolution exposure. The excellent effect that can be formed is obtained.

[Examples concerning image quality evaluation when an image is formed]
[Preparing toner]
[Measurement method and definition of volume average diameter (Mv)]
The volume average diameter (Mv) of the particles having a volume average diameter (Mv) of less than 1 μm is determined by the handling of nanotracks using Nikkiso Co., Ltd., model: Microtrac Nanotrac 150 (hereinafter abbreviated as “nanotrack”). According to the instructions, the company's analysis software Microtrac Particle Analyzer Ver10.1.2. Using −019EE, ion-exchanged water having an electric conductivity of 0.5 μS / cm was used as a dispersion medium, and measurement was performed by the method described in the instruction manual under the following conditions or the following conditions, respectively.

The following conditions were used for the wax dispersion and the polymer primary particle dispersion.
Solvent refractive index: 1.333
-Measurement time: 100 seconds-Number of measurements: 1 time-Particle refractive index: 1.59
-Permeability: Transmission-Shape: True spherical shape-Density: 1.04

The following conditions were used for the pigment premix solution and the colorant dispersion.
Solvent refractive index: 1.333
-Measurement time: 100 seconds-Number of measurements: 1 time-Particle refractive index: 1.59
・ Transparency: Absorption ・ Shape: Non-spherical shape ・ Density: 1.00

[Measurement method and definition of volume median diameter (Dv50)]
As a pre-measurement treatment of the toner finally obtained through the external addition step, the following was performed. In a cylindrical polyethylene (PE) beaker having an inner diameter of 47 mm and a height of 51 mm, 0.100 g of toner using a spatula, 20% by weight DBS aqueous solution using a dropper (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) 0.15 g was mixed. At this time, toner and a 20% DBS aqueous solution were added only to the bottom of the beaker so that the toner would not scatter on the edge of the beaker. Next, the mixture was stirred for 3 minutes using a spatula until the toner and 20% DBS aqueous solution became a paste. At this time, the toner was prevented from being scattered on the edge of the beaker.

  Subsequently, 30 g of dispersion medium Isoton II (manufactured by Beckman Coulter, Inc.) was mixed, stirred for 2 minutes using a spatula, and the whole was made into a uniform solution visually. Next, a fluororesin-coated rotor having a length of 31 mm and a diameter of 6 mm was placed in a beaker and dispersed using a stirrer at 400 rpm for 20 minutes. At this time, using a spatula at a rate of once every 3 minutes, macroscopic particles visually observed at the gas-liquid interface and the edge of the beaker were dropped into the beaker so as to form a uniform dispersion. Subsequently, this was filtered through a mesh having an opening of 63 μm, and the obtained filtrate was designated as “toner dispersion”.

  Regarding the measurement of the particle diameter during the production process of the toner base particles, the filtrate obtained by filtering the agglomerated slurry with a 63 μm mesh was used as the “slurry liquid”.

  The volume median diameter (Dv50) of the particles is Bocman Coulter's Multisizer III (aperture diameter 100 μm) (hereinafter abbreviated as “Multisizer”), the dispersion medium is Isoton II, and the above-mentioned “ The “toner dispersion liquid” or “slurry liquid” was diluted to a dispersoid concentration of 0.03% by mass and measured with Multisizer III analysis software with a KD value of 118.5. The measurement particle size range is from 2.00 to 64.00 μm, and this range is discretized into 256 divisions at equal intervals on a logarithmic scale, and the volume calculated based on the statistical values on the basis of the volume The median diameter (Dv50) was used.

[Measurement Method and Definition of Number% (Dns) of Toner with Particle Size of 2.00 μm to 3.56 μm]
As a pre-measurement process for the toner after the external addition step, the following procedure was performed. In a cylindrical polyethylene (PE) beaker having an inner diameter of 47 mm and a height of 51 mm, 0.100 g of toner using a spatula, 20% by weight DBS aqueous solution using a dropper (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) 0.15 g was mixed. At this time, toner and a 20% DBS aqueous solution were added only to the bottom of the beaker so that the toner would not scatter on the edge of the beaker. Next, the mixture was stirred for 3 minutes using a spatula until the toner and 20% DBS aqueous solution became a paste. At this time, the toner was prevented from being scattered on the edge of the beaker.

  Subsequently, 30 g of the dispersion medium Isoton II was mixed, and stirred for 2 minutes using a spatula to make a uniform solution as a whole. Next, a fluororesin-coated rotor having a length of 31 mm and a diameter of 6 mm was placed in a beaker and dispersed using a stirrer at 400 rpm for 20 minutes. At this time, macroscopic particles visually observed at the gas-liquid interface and the edge of the beaker were dropped into the beaker at a rate of once every 3 minutes so as to form a uniform dispersion. Subsequently, this was filtered with a mesh having an opening of 63 μm, and the obtained filtrate was used as a toner dispersion.

  For the number% (Dns) of toner having a particle size of 2.00 μm or more and 3.56 μm or less, a multisizer (aperture diameter 100 μm) is used, and Isoton II manufactured by the same company is used as a dispersion medium. The “slurry liquid” was diluted to a dispersoid concentration of 0.03% by mass and measured with Multisizer III analysis software with a KD value of 118.5.

  The lower limit particle size of 2.00 μm is the detection limit of the measuring device multisizer, and the upper limit particle size of 3.56 μm is a prescribed channel value in the measuring device multisizer. In the present invention, an area having a particle size of 2.00 μm or more and 3.56 μm or less is recognized as a fine powder area.

  The measurement particle size range is from 2.00 μm to 64.00 μm, and this range is discretized into 256 divisions so as to be equally spaced on a logarithmic scale. To 3.56 μm, the ratio of the particle size component was calculated on the basis of the number and was defined as “Dns”. In the case where the toner is one obtained by fixing or adhering an external additive to the surface of the toner base particles, it was measured as a measurement sample.

[Measurement method and definition of average circularity]
“Average circularity” was measured as follows and defined as follows. That is, the toner base particles are dispersed in a dispersion medium (Isoton II, manufactured by Beckman Coulter, Inc.) in a range of 5720 / μL or more and 7140 / μL or less, and a flow type particle image analyzer (Sysmex Corporation (formerly Toa) Using FPIA2100) manufactured by Medical Electronics Co., Ltd., measurement is performed under the following apparatus conditions, and the value is defined as “average circularity”. In the following examples, the same measurement is performed three times, and an arithmetic average value of three “average circularity” is adopted as the “average circularity”. In the case where the toner is one obtained by fixing or adhering an external additive to the surface of the toner base particles, it was measured as a measurement sample.
・ Mode: HPF
-HPF analysis amount: 0.35 μL
-HPF detection number: 2000-2500

The following is measured by the above-mentioned apparatus, and automatically calculated and displayed in the above-mentioned apparatus. “Circularity” is defined by the following equation.
[Circularity] = [Perimeter of a circle with the same area as the projected particle area] / [Perimeter of projected particle image]
Then, 2000 or more and 2500 or less, which is the number of HPF detected, is measured, and the arithmetic average (arithmetic mean) of the circularity of each particle is displayed on the apparatus as “average circularity”.

[Method and definition of number variation coefficient]
The “number variation coefficient” in the present invention is defined as follows.
[Number variation coefficient] = 100 × [standard deviation of particle distribution based on number] / [number average particle diameter]

  The standard deviation of the number-based particle distribution and the number average particle diameter were measured using Multisizer III according to the method of measuring the volume median diameter (Dv50). The measurement particle range is from 2.00 μm to 64.00 μm, and this range is discretized into 256 divisions at equal intervals in the logarithmic memory, and the number-based particle distribution based on the statistical values based on the number-based number. The standard deviation and the number average particle diameter were determined, and the number variation coefficient was calculated from the above formula. In the case where the toner is one obtained by fixing or adhering an external additive to the surface of the toner base particles, it was measured as a measurement sample.

[Measurement method of electrical conductivity]
The electrical conductivity was measured using a conductivity meter (a personal SC meter model SC72 and a detector SC72SN-11 manufactured by Yokogawa Electric Corporation) according to an ordinary method according to the instruction manual.

[Measuring method of melting point peak temperature, melting peak half width, crystallization temperature, crystallization peak half width]
From the endothermic curve when the temperature is raised from 10 ° C. to 110 ° C. at a rate of 10 ° C./min using the method described in the company's instruction manual using Seiko Instruments Inc. model: SSC5200, the melting point peak temperature The half-width of the melting peak was measured, and then the crystallization temperature and the half-width of the crystallization peak were measured from the exothermic curve when the temperature was lowered from 110 ° C. to 10 ° C. at a rate of 10 ° C./min.

[Measurement method of solid content concentration]
Using a solid content concentration measuring instrument INFRARED MOISTURE DETERMINATION BALANCE model FD-100, manufactured by Kett Science Laboratory, weighed 1.00 g of a sample containing solid content on a balance, and the conditions of a heater temperature of 300 ° C. and a heating time of 90 minutes The solid content concentration was measured.

[Measurement method of charge amount distribution (standard deviation of charge amount)]
0.8 g of toner / carrier (19.2 g of ferrite carrier manufactured by Powdertech Co., Ltd.) was placed in a glass sample bottle and stirred for 30 minutes at 250 rpm using a reciprocating shaker NR-1 (manufactured by Taitec Corporation). The stirred toner / carrier mixture was subjected to charge amount distribution measurement using an E-Spart charge amount distribution measuring apparatus (manufactured by Hosokawa Micron Corporation). The value obtained by dividing the charge amount of each particle by the particle diameter is obtained from the obtained data (the range from −16.197 C / μm to +16.197 C / μm is discretized into 128 divisions every 0.2551 C / μm). The standard deviation of the 3000 particle measurement results was obtained and used as the standard deviation of the charge amount.

[Toner Production Example 1]
(Preparation of wax / long-chain polymerizable monomer dispersion A1)
Paraffin wax (Nihon Seiki Co., Ltd. HNP-9, surface tension 23.5 mN / m, thermal characteristics: melting point peak temperature 82 ° C., melting heat 220 J / g, melting peak half width 8.2 ° C., crystallization temperature 66 ° C., Crystallization peak half-value width 13.0 ° C.) 27 parts (540 g), stearyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) 2.8 parts, 20 mass% sodium dodecylbenzenesulfonate aqueous solution (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S20A) ( (Hereinafter abbreviated as “20% DBS aqueous solution”) 1.9 parts and 68.3 parts of demineralized water are heated to 90 ° C. and stirred for 10 minutes using a homomixer (Mark II f model, manufactured by Tokushu Kika Kogyo Co., Ltd.). did.

  Next, this dispersion was heated to 90 ° C., and circulation emulsification was started under a pressure condition of 25 MPa using a homogenizer (manufactured by Gorin, 15-M-8PA type). Dispersion was carried out until (Mv) reached 250 nm to prepare a wax / long-chain polymerizable monomer dispersion A1 (emulsion solid content concentration = 30.2 mass%).

(Preparation of polymer primary particle dispersion A1)
In a reactor (inner volume 21 L, inner diameter 250 mm, height 420 mm) equipped with a stirrer (three blades), a heating / cooling device, a concentrating device, and a raw material / auxiliary charging device, the wax / long-chain polymerizable unit is added. The monomer dispersion A1 (35.6 parts, 712.12 g) and 259 parts of demineralized water were charged, and the temperature was raised to 90 ° C. under a nitrogen stream while stirring.

  Thereafter, the mixture of the following “polymerizable monomers and the like” and “emulsifier aqueous solution” was mixed there over 5 hours while continuing to stir the liquid. The point of time when this mixture was started to be dropped was designated as “polymerization start”, the following “initiator aqueous solution” was mixed for 4.5 hours from 30 minutes after the start of polymerization, and further 5 hours after the start of polymerization, The aqueous agent solution ”was mixed over 2 hours, and further maintained with stirring at an internal temperature of 90 ° C. for 1 hour.

[Polymerizable monomers, etc.]
Styrene 76.8 parts (1535.0 g)
Butyl acrylate 23.2 parts Acrylic acid 1.5 parts Hexanediol diacrylate 0.7 parts Trichlorobromomethane 1.0 part

[Emulsifier aqueous solution]
20% DBS aqueous solution 1.0 part Demineralized water 67.1 parts

[Initiator aqueous solution]
8% by mass aqueous hydrogen peroxide solution 15.5 parts 8% by mass L (+)-ascorbic acid aqueous solution 15.5 parts

[Additive initiator aqueous solution]
8 mass% L (+)-ascorbic acid aqueous solution 14.2 parts

  After the completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion A1. The volume average diameter (Mv) measured using Nanotrac was 280 nm, and the solid content concentration was 21.1% by mass.

(Preparation of polymer primary particle dispersion A2)
A 20 mass% DBS aqueous solution 1.0 was added to a reactor (inner volume 21 L, inner diameter 250 mm, height 420 mm) equipped with a stirrer (three blades), a heating / cooling device, a concentrating device, and a raw material / auxiliary charging device. Part, 312 parts of demineralized water, heated to 90 ° C. under a nitrogen stream, 3.2 parts of 8% by weight aqueous hydrogen peroxide solution and 3.2 parts of 8% by weight L (+)-ascorbic acid aqueous solution with stirring. Were mixed together. The time point after 5 minutes from the time of mixing these together is defined as “polymerization start”.

  Thereafter, a mixture of the following “polymerizable monomers and the like” and “emulsifier aqueous solution” was mixed for 5 hours from the start of polymerization, and the following “initiator aqueous solution” was mixed for 6 hours from the start of polymerization. The inner temperature was maintained at 90 ° C. for 1 hour with further stirring.

[Polymerizable monomers, etc.]
92.5 parts of styrene (1850.0 g)
Butyl acrylate 7.5 parts Acrylic acid 0.5 parts Trichlorobromomethane 0.5 parts

[Emulsifier aqueous solution]
20% DBS aqueous solution 1.5 parts Demineralized water 66.0 parts

[Initiator aqueous solution]
8% by mass aqueous hydrogen peroxide solution 18.9 parts 8% by mass L (+)-ascorbic acid aqueous solution 18.9 parts

  After completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion A2. The volume average diameter (Mv) measured using Nanotrac was 290 nm, and the solid content concentration was 19.0% by mass.

(Preparation of colorant dispersion A)
Carbon black (Mitsubishi Chemical Co., Ltd.) manufactured by a furnace method with a 300 L internal volume equipped with a stirrer (propeller blade) and a toluene extract having an ultraviolet absorbance of 0.02 and a true density of 1.8 g / cm ³ Mitsubishi Carbon Black MA100S) 20 parts (40 kg), 20% DBS aqueous solution 1 part, nonionic surfactant (manufactured by Kao Corp., Emulgen 120) 4 parts, ion-exchanged water 75 parts with an electric conductivity of 2 μS / cm In addition, it was predispersed to obtain a pigment premix solution. The volume average diameter (Mv) of carbon black in the dispersion after pigment premixing measured with Nanotrac was 90 μm.

The pigment premix solution was supplied as a raw material slurry to a wet bead mill and subjected to one-pass dispersion. The inner diameter of the stator was φ75 mm, the separator diameter was φ60 mm, the distance between the separator and the disk was 15 mm, and zirconia beads having a diameter of 100 μm (true density of 6.0 g / cm ³ ) were used as a dispersion medium. Since the effective internal volume of the stator is 0.5 L and the filling volume of the media is 0.35 L, the media filling rate is 70% by mass. The pigment premix liquid is continuously supplied from the supply port at a supply speed of 50 L / hr by a non-pulsating metering pump, and the rotor rotation speed is constant (peripheral speed at the rotor tip is 11 m / sec), and continuously from the discharge port. To obtain a black colorant dispersion A. The volume average diameter (Mv) of the colorant dispersion A measured with Nanotrac was 150 nm, and the solid content concentration was 24.2% by mass.

(Production of toner mother particle A)
By using the following components, toner base particles A were produced by performing the following aggregation processes (core material aggregation process, shell coating process), circularization process, washing process, and drying process.
Polymer primary particle dispersion A1 95 parts as solid content (998.2 g as solid content)
Polymer primary particle dispersion A2 5 parts as solid content Colorant dispersion A 6 parts as colorant solid content 20% DBS aqueous solution In the core material agglomeration step, 0.2 parts 20% DBS aqueous solution as solid content In the circularization step, 6 parts solids

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device The liquid A1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, with stirring at 250 ° C. at an internal temperature of 7 ° C., 0.52 parts of FeSO ₄ .7H ₂ O as a 5% by mass aqueous solution of ferrous sulfate was mixed over 5 minutes, and then colorant dispersion A Were mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aluminum sulfate aqueous solution was added dropwise over 8 minutes under the same conditions (solid content relative to resin solid content). 0.10 parts). Thereafter, the internal temperature was raised to 54.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.32 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was mixed for 3 minutes while maintaining the internal temperature of 54.0 ° C and the rotation speed of 250 rpm, and held as it was for 60 minutes.

○ Circularization process Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (solid content) 6 parts) for 10 minutes, and then heated to 81 ° C. over 30 minutes, and heating and stirring were continued under these conditions until the average circularity reached 0.943. Thereafter, the mixture was cooled to 30 ° C. over 20 minutes to obtain a slurry.

Washing step The obtained slurry was extracted and suction filtered with an aspirator using 5 types C (Toyo Filter Paper No. 5C) filter paper. The cake remaining on the filter paper is transferred to a stainless steel container having an internal volume of 10 L equipped with a stirrer (propeller blade), and 8 kg of ion exchange water having an electric conductivity of 1 μS / cm is added and stirred uniformly at 50 rpm. Thereafter, stirring was continued for 30 minutes.

  Thereafter, the filter paper was suction filtered with an aspirator again using Type 5 C (Toyo Filter Paper No. 5C) filter paper, and the solid matter remaining on the filter paper was again equipped with a stirrer (propeller blade) with an electrical conductivity of 1 μS / cm. It was transferred to a container with an internal volume of 10 L containing 8 kg of ion-exchanged water, and uniformly dispersed by stirring at 50 rpm and kept stirring for 30 minutes. When this process was repeated 5 times, the electrical conductivity of the filtrate was 2 μS / cm.

○ Drying step The solid material obtained here was spread on a stainless steel bat so that the height was 20 mm, and dried in a blow dryer set at 40 ° C. for 48 hours to obtain toner mother particles A.

(Manufacture of toner A)
External Addition Step To 250 g of the obtained toner base particles A, 1.55 g of H2000 silica manufactured by Clariant and 0.62 g of SMT150IB titania fine powder manufactured by Teika are mixed as an external additive, and a sample mill (manufactured by Kyoritsu Riko) is used. The toner A was obtained by mixing at 6000 rpm for 1 minute and sieving with 150 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured using the toner A multisizer obtained here is 5.54 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 3.83%, the average circularity was 0.943, and the number variation coefficient was 18.6%.

[Toner Production Example 2]
(Production of toner mother particle B)
In the agglomeration step (core material agglomeration step, shell coating step), rounding step, washing step and drying step of “manufacturing toner mother particle A”, “core material agglomeration step”, “shell coating step” and “circularization step” The toner mother particles B were obtained in the same manner as in “Production of toner mother particles A” in Toner Production Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device The liquid A1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 wt% aqueous solution of ferrous sulfate was mixed as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant Dispersion A was mixed over 5 minutes, uniformly mixed at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes under the same conditions (based on the resin solid content). Solid content is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.86 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was mixed for 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed at 250 rpm, and held as it was for 60 minutes.

○ Circularization process Subsequently, the rotation speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotation speed of the aggregation process), and then a 20% DBS aqueous solution (as solid content) 6 parts) was mixed over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.942. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

[Production of Toner B]
Thereafter, the toner B was prepared in the same manner as in “Production of Toner A” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

Analyzing Step The volume median diameter (Dv50) measured by using the multisizer of toner B obtained here is 5.97 μm, and “the number% of toner having a particle diameter of 2.00 μm to 3.56 μm (Dns ) ”Was 2.53%, the average circularity was 0.943, and the number variation coefficient was 18.4%.

[Toner Production Example 3]
(Production of toner mother particles C)
In the agglomeration step (core material agglomeration step, shell coating step), rounding step, washing step and drying step of “manufacturing toner mother particle A”, “core material agglomeration step”, “shell coating step” and “circularization step” The toner mother particles C were obtained in the same manner as in “Production of toner mother particles A” in Toner Production Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device The liquid A1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and stirring at 250 rpm, 0.52 parts of FeSO ₄ · 7H ₂ O was mixed with 5% by mass aqueous solution of ferrous sulfate over 5 minutes, and then the colorant was dispersed. Liquid A was mixed over 5 minutes, uniformly mixed at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes under the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 57.0 ° C. while maintaining the rotational speed of 250 rpm, and the volume median diameter (Dv50) was measured using a multisizer to grow it to 6.72 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was mixed for 3 minutes while maintaining the internal temperature at 57.0 ° C and the rotational speed of 250 rpm, and held as it was for 60 minutes.

○ Circularization process Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (solid content) 6 parts) was mixed over 10 minutes, and then heated to 87 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.941. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

(Manufacture of toner C)
Thereafter, the toner C was prepared in the same manner as in “Production of toner A” except that the amount of H2000 silica as an external additive was changed to 1.25 g and the amount of SMT150IB titania fine powder was changed to 0.50 g. Got.

Analyzing Step The volume median diameter (Dv50) measured by using the multisizer of toner C obtained here is 6.75 μm, and “the number% of toner having a particle diameter of 2.00 μm to 3.56 μm (Dns ) ”Was 1.83%, the average circularity was 0.942, and the number variation coefficient was 18.7%.

[Toner Production Example 4]
(Manufacture of toner mother particles D)
In the agglomeration step (core material agglomeration step, shell coating step), rounding step, washing step and drying step of “manufacturing toner mother particle A”, “core material agglomeration step”, “shell coating step” and “circularization step” The toner mother particles D were obtained in the same manner as in “Production of toner mother particles A” in Toner Production Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device The liquid A1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 21 ° C. and stirring at 250 rpm, 0.52 parts of FeSO ₄ · 7H ₂ O was mixed with 5% by mass aqueous solution of ferrous sulfate over 5 minutes, and then the colorant was dispersed. Liquid A was mixed over 5 minutes, uniformly mixed at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes under the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 54.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.34 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was mixed for 3 minutes while maintaining the internal temperature of 54.0 ° C and the rotation speed of 250 rpm, and held as it was for 60 minutes.

○ Circularization process Subsequently, the rotation speed was reduced to 220 rpm (circumferential speed 2.28 m / sec at the tip of the stirring blade, stirring speed reduced by 12% with respect to the aggregation process rotation speed), and then 20% DBS aqueous solution (as solid content) 6 parts) was mixed over 10 minutes, then heated to 81 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.942. Then, it cooled to 30 degreeC over 20 minutes, and obtained the slurry.

(Manufacture of toner D)
Thereafter, a toner D was obtained by the same operation of the external addition process as in “Production of Toner A” in Toner Production Example 1.

Analyzing Step The volume median diameter (Dv50) of the toner D obtained here measured using a multisizer is 5.48 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm (Dns ) "Was 4.51%, the average circularity was 0.943, and the number variation coefficient was 20.4%.

[Toner Production Example 5]
(Manufacture of toner mother particles E)
In the agglomeration step (core material agglomeration step, shell coating step), rounding step, washing step and drying step of “manufacturing toner mother particle A”, “core material agglomeration step”, “shell coating step” and “circularization step” The toner mother particles E were obtained in the same manner as in “Production of toner mother particles A” in Toner Production Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device The liquid A1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 21 ° C. and stirring at 250 rpm, 0.52 parts of FeSO ₄ · 7H ₂ O was mixed with 5% by mass aqueous solution of ferrous sulfate over 5 minutes, and then the colorant was dispersed. Liquid A was mixed over 5 minutes, uniformly mixed at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes under the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.86 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was mixed for 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed at 250 rpm, and held as it was for 60 minutes.

○ Circularization process Subsequently, the rotational speed was reduced to 220 rpm (a peripheral speed of 2.28 m / second at the tip of the stirring blade, a stirring speed reduced by 12% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (solid content) 6 parts) over 10 minutes, and then heated to 84 ° C. over 30 minutes and continued to heat and stir until the average circularity reached 0.941. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

(Manufacture of toner E)
Thereafter, the toner E was changed in the same manner as in “Production of Toner A” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

Analyzing Step The volume median diameter (Dv50) measured using a multisizer of the developing toner E obtained here is 5.93 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 3.62%, the average circularity was 0.942, and the number variation coefficient was 20.1%.

[Toner Production Example 6]
(Manufacture of toner mother particles F)
In the agglomeration step (core material agglomeration step, shell coating step), rounding step, washing step and drying step of “manufacturing toner mother particle A”, “core material agglomeration step”, “shell coating step” and “circularization step” The toner mother particles F were obtained in the same manner as in “Production of toner mother particles A” in Toner Production Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device The liquid A1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 21 ° C. and stirring at 250 rpm, 0.52 parts of FeSO ₄ · 7H ₂ O was mixed with 5% by mass aqueous solution of ferrous sulfate over 5 minutes, and then the colorant was dispersed. Liquid A was mixed over 5 minutes, uniformly mixed at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes under the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 57.0 ° C. while maintaining the rotational speed of 250 rpm, and the volume median diameter (Dv50) was measured using a multisizer to grow it to 6.76 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was mixed for 3 minutes while maintaining the internal temperature at 57.0 ° C and the rotational speed of 250 rpm, and held as it was for 60 minutes.

○ Circularization process Subsequently, the rotational speed was reduced to 220 rpm (a peripheral speed of 2.28 m / second at the tip of the stirring blade, a stirring speed reduced by 12% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (solid content) 6 parts) was mixed over 10 minutes, and then heated to 87 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.941. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

(Manufacture of toner F)
Thereafter, the amount of H2000 silica as an external additive was changed to 1.25 g, and the amount of SMT150IB titania fine powder was changed to 0.50 g. Got.

Analyzing Step The volume median diameter (Dv50) measured by using the multisizer of toner F obtained here is 6.77 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm (Dns ) ”Was 2.48%, the average circularity was 0.942, and the number variation coefficient was 21.1%.

[Toner Comparative Production Example 1]
(Manufacture of toner mother particles G)
In the agglomeration step (core material agglomeration step, shell coating step), rounding step, washing step and drying step of “manufacturing toner mother particle A”, “core material agglomeration step”, “shell coating step” and “circularization step” The toner mother particles G were obtained in the same manner as in “Production of toner mother particles A” in Toner Production Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device The liquid A1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 21 ° C. and stirring continuously at 250 rpm, 0.52 parts of FeSO ₄ · 7H ₂ O as a 5% by mass aqueous solution of ferrous sulfate was mixed together in 5 minutes, and then the colorant was dispersed. Liquid A was mixed all at once in 5 minutes, uniformly mixed at an internal temperature of 7 ° C., and further mixed with 0.5 mass% aluminum sulfate aqueous solution in 8 seconds under the same conditions (solid to resin solid content). Min is 0.10 parts). Thereafter, the internal temperature was raised to 57.0 ° C. while maintaining the rotational speed of 250 rpm, and the volume median diameter (Dv50) was measured using a multisizer to grow to 6.85 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was mixed in 3 minutes and held for 60 minutes with the internal temperature of 57.0 ° C. and the rotation speed of 250 rpm.

○ Circularization process Subsequently, 20% DBS aqueous solution (6 parts as solid content) was maintained for 10 minutes while maintaining the rotational speed at 250 rpm (peripheral speed 2.59 m / sec at the tip of the stirring blade, the same stirring speed as the aggregation process rotational speed). Then, the temperature was raised to 87 ° C. over 30 minutes, and heating and stirring were continued until the average circularity became 0.942. Thereafter, the mixture was cooled to 30 ° C. over 20 minutes to obtain a slurry.

(Manufacture of toner G)
Thereafter, the toner G was prepared in the same manner as in “Production of Toner A” except that the amount of H2000 silica as an external additive was changed to 1.25 g and the amount of SMT150IB titania fine powder was changed to 0.50 g. Got.

○ Analyzing step The volume median diameter (Dv50) measured using a multisizer of the developing toner G obtained here is 6.79 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 4.52%, the average circularity was 0.943, and the number variation coefficient was 24.5%.

[Toner Production Example 7]
(Preparation of wax / long-chain polymerizable monomer dispersion H1)
Paraffin wax (Nihon Seiki Co., Ltd. HNP-9, surface tension 23.5 mN / m, thermal characteristics: melting point peak temperature 82 ° C., melting heat 220 J / g, melting peak half width 8.2 ° C., crystallization temperature 66 ° C., 27 parts (540 g) of crystallization peak half-value width of 13.0 ° C., 2.8 parts of stearyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 1.9 parts of 20% DBS aqueous solution, and 68.3 parts of demineralized water were heated to 90 ° C. Then, the mixture was stirred for 10 minutes using a homomixer (Mark II f model, manufactured by Tokushu Kaika Co., Ltd.).

  Next, this dispersion was heated to 90 ° C., and circulation emulsification was started under a pressure condition of 25 MPa using a homogenizer (manufactured by Gorin, 15-M-8PA type). Dispersion was carried out until (Mv) reached 250 nm to prepare a wax / long-chain polymerizable monomer dispersion H1 (emulsion solid content concentration = 30.2 mass%).

(Preparation of polymer primary particle dispersion H1)
In a reactor (inner volume 21 L, inner diameter 250 mm, height 420 mm) equipped with a stirrer (three blades), a heating / cooling device, a concentrating device, and a raw material / auxiliary charging device, the wax / long-chain polymerizable unit is added. The monomer dispersion H1 (35.6 parts, 712.12 g) and demineralized water (259 parts) were charged, and the temperature was raised to 90 ° C. under a nitrogen stream while stirring.

  Thereafter, the mixture of the following “polymerizable monomers and the like” and “emulsifier aqueous solution” was mixed there over 5 hours while continuing to stir the liquid. The point of time when this mixture was started to be dropped was designated as “polymerization start”, the following “initiator aqueous solution” was mixed for 4.5 hours from 30 minutes after the start of polymerization, and further 5 hours after the start of polymerization, The aqueous agent solution ”was mixed over 2 hours, and further maintained with stirring at an internal temperature of 90 ° C. for 1 hour.

[Polymerizable monomers, etc.]
Styrene 76.8 parts (1535.0 g)
Butyl acrylate 23.2 parts Acrylic acid 1.5 parts Hexanediol diacrylate 0.7 parts Trichlorobromomethane 1.0 part

[Emulsifier aqueous solution]
20% DBS aqueous solution 1.0 part Demineralized water 67.1 parts

[Initiator aqueous solution]
8% by mass aqueous hydrogen peroxide solution 15.5 parts 8% by mass L (+)-ascorbic acid aqueous solution 15.5 parts

[Additive initiator aqueous solution]
8 mass% L (+)-ascorbic acid aqueous solution 14.2 parts

  After completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion H1. The volume average diameter (Mv) measured using Nanotrac was 265 nm, and the solid content concentration was 22.3 mass%.

(Preparation of silicone wax dispersion H2)
Alkyl-modified silicone wax (thermal characteristics: melting point peak temperature 77 ° C., heat of fusion 97 J / g, melting peak half width 10.9 ° C., crystallization temperature 61 ° C., crystallization peak half width 17.0 ° C.) 27 parts (540 g) Then, 1.9 parts of a 20% DBS aqueous solution and 71.1 parts of demineralized water were placed in a 3 L stainless steel container, heated to 90 ° C., and stirred for 10 minutes with a homomixer (Mark II f model manufactured by Tokushu Kika Kogyo Co., Ltd.). Next, this dispersion was heated to 99 ° C., and circulation emulsification was started under a pressure of 45 MPa using a homogenizer (manufactured by Gorin Co., Ltd., 15-M-8PA type). ) To 240 nm to prepare a silicone wax dispersion H2 (emulsion solid content concentration = 27.3%).

(Preparation of polymer primary particle dispersion H2)
Silicone wax dispersion H2 was added to a reactor (inner volume 21 L, inner diameter 250 mm, height 420 mm) equipped with a stirrer (three blades), a heating / cooling device, a concentrating device, and a raw material / auxiliary charging device 23. 3 parts (466 g), 20% DBS aqueous solution 1.0 part and demineralized water 324 parts were charged, heated to 90 ° C. under a nitrogen stream, and stirred with stirring 8% hydrogen peroxide aqueous solution 3.2 parts, 8% L 3.2 parts of (+)-ascorbic acid aqueous solution was mixed together. The time point after 5 minutes from the time of mixing these together is defined as “polymerization start”.

  A mixture of the following “polymerizable monomers and the like” and “emulsifier aqueous solution” was mixed for 5 hours from the start of polymerization, and the following “initiator aqueous solution” was mixed for 6 hours from the start of polymerization. While stirring, the internal temperature was maintained at 90 ° C. for 1 hour.

[Polymerizable monomers, etc.]
92.5 parts of styrene (1850.0 g)
Butyl acrylate 7.5 parts Acrylic acid 1.5 parts Trichlorobromomethane 0.6 parts

[Emulsifier aqueous solution]
20% DBS aqueous solution 1.0 part Demineralized water 67.0 parts

[Initiator aqueous solution]
8% by mass aqueous hydrogen peroxide solution 18.9 parts 8% by mass L (+)-ascorbic acid aqueous solution 18.9 parts

  After completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion H2. The volume average diameter (Mv) measured using Nanotrac was 290 nm, and the solid content concentration was 19.0% by mass.

[Preparation of Colorant Dispersion H]
Carbon black (Mitsubishi Chemical Co., Ltd.) manufactured by a furnace method with a 300 L internal volume equipped with a stirrer (propeller blade) and a toluene extract having an ultraviolet absorbance of 0.02 and a true density of 1.8 g / cm ³ Mitsubishi Carbon Black MA100S) 20 parts (40 kg), 20% DBS aqueous solution 1 part, nonionic surfactant (manufactured by Kao Corp., Emulgen 120) 4 parts, ion-exchanged water 75 parts with an electric conductivity of 2 μS / cm In addition, it was predispersed to obtain a pigment premix solution. The volume average diameter (Mv) of carbon black in the dispersion after pigment premixing measured with Nanotrac was 90 μm.

The pigment premix solution was supplied as a raw material slurry to a wet bead mill and subjected to one-pass dispersion. The stator inner diameter was 75 mmφ, the separator diameter was 60 mmφ, the distance between the separator and the disk was 15 mm, and zirconia beads having a diameter of 100 μm (true density 6.0 g / cm ³ ) were used as the dispersing medium. Since the effective internal volume of the stator is 0.5 L and the filling volume of the media is 0.35 L, the media filling rate is 70% by mass. The pigment premix liquid is continuously supplied from the supply port at a supply speed of 50 L / hr by a non-pulsating metering pump, and the rotor rotation speed is constant (peripheral speed at the rotor tip is 11 m / sec), and continuously from the discharge port. To obtain a black colorant dispersion H. The volume average diameter (Mv) of the colorant dispersion H measured with Nanotrac was 150 nm, and the solid content concentration was 24.2% by mass.

(Production of toner mother particles H)
Using the following components, toner base particles H were produced by carrying out the following aggregation processes (core material aggregation process, shell coating process), circularization process, washing process and drying process.
Polymer primary particle dispersion H1 90 parts as solids (958.9 g as solids)
Polymer primary particle dispersion H2 10 parts colorant dispersion H as solid content 4.4 parts 20% DBS aqueous solution as colorant solid content In the core material agglomeration step, 0.15 part 20% DBS aqueous solution as solid content Circularization step Then, 6 parts as solid content

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Then at an internal temperature of 10 ° C., allowed to stir at 280 rpm, a 5 mass% aqueous solution of potassium _sulfate, 0.12 parts of a continuously mixed for 1 minute as K 2 SO _4, the colorant dispersion H 5 The mixture was continuously mixed over a period of time and uniformly mixed at an internal temperature of 10 ° C.

  Thereafter, 100 parts of demineralized water was continuously mixed for 30 minutes, and then the internal temperature was raised to 48.0 ° C. over 67 minutes (0.5 ° C./min) while maintaining the rotational speed of 280 rpm. Next, after raising the temperature by 1 ° C. every 30 minutes (0.03 ° C./min), hold at 54.0 ° C., measure the volume median diameter (Dv50) using a multisizer, and grow to 5.15 μm. It was.

The stirring conditions at this time are as follows.
(A) Diameter of the stirring vessel (as a so-called general cylindrical shape): 208 mm
(B) Height of stirring container: 355 mm
(C) Peripheral speed at the tip of the stirring blade: 280 rpm, that is, 2.78 m / sec.
(D) Shape of stirring blade: Double helical blade (diameter 190mm, height 270mm, width 20mm)
(E) Position of the blade in the stirring vessel: 5 mm above the bottom of the vessel.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously mixed for 6 minutes while maintaining the internal temperature of 54.0 ° C and the rotational speed of 280 rpm, and held for 60 minutes. At this time, the Dv50 of the particles was 5.34 μm.

○ Circularization Step Subsequently, the temperature was raised to 83 ° C. while mixing a mixed aqueous solution of 20% DBS aqueous solution (6 parts as a solid content) and 0.04 part of water over 30 minutes, and thereafter 1 every 30 minutes. The temperature was raised to 88 ° C., and heating and stirring were continued under these conditions until the average circularity reached 0.939 over 3.5 hours. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, the Dv50 of the particles was 5.33 μm and the average circularity was 0.937.

Washing step The obtained slurry was extracted and suction filtered with an aspirator using 5 types C (Toyo Filter Paper No. 5C) filter paper. The cake remaining on the filter paper is transferred to a stainless steel container having an internal volume of 10 L equipped with a stirrer (propeller blade), and 8 kg of ion exchange water having an electric conductivity of 1 μS / cm is added and stirred uniformly at 50 rpm. Thereafter, stirring was continued for 30 minutes.

  Thereafter, the filter paper was suction filtered with an aspirator again using Type 5 C (Toyo Filter Paper No. 5C) filter paper, and the solid matter remaining on the filter paper was again equipped with a stirrer (propeller blade) with an electrical conductivity of 1 μS / cm. It was transferred to a container with an internal volume of 10 L containing 8 kg of ion-exchanged water, and uniformly dispersed by stirring at 50 rpm and kept stirring for 30 minutes. When this process was repeated 5 times, the electrical conductivity of the filtrate was 2 μS / cm.

○ Drying step The solid material obtained here was spread on a stainless steel vat so as to have a height of 20 mm, and dried in a blow dryer set at 40 ° C. for 48 hours to obtain toner mother particles H.

(Manufacture of toner H)
External Addition Step To the obtained toner base particle H500 g, 8.75 g of Clariant H30TD silica as an external additive is mixed and mixed with a 9 L Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) at 3000 rpm for 30 minutes. 1.4 g of HAP-05NP calcium phosphate manufactured by Calcium Co., Ltd. was mixed, mixed at 3000 rpm for 10 minutes, and sieved with 200 mesh to obtain toner H.

Analyzing Step The “volume median diameter (Dv50)” measured using a multisizer of the toner H obtained here is 5.26 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 5.87%, the average circularity was 0.948, and the number variation coefficient was 18.0%.

[Toner Production Example 8]
(Production of toner mother particle I)
In the aggregation process (core material aggregation process, shell coating process), rounding process, washing process and drying process of “manufacturing toner mother particles H”, “core material aggregation process”, “shell coating process” and “rounding process” The toner mother particles I were obtained in the same manner as in “Production of toner mother particles H” in Toner Production Example 7 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 5 minutes. Subsequently, the mixture was stirred at 280 rpm at an internal temperature of 10 ° C. and 0.12 part of a 5% by weight aqueous solution of potassium sulfate was continuously mixed over 1 minute, and then the colorant dispersion H was continuously mixed over 5 minutes. Mix evenly at a temperature of 10 ° C. Thereafter, 100 parts of demineralized water was continuously mixed for 26 minutes, and then the internal temperature was raised to 52.0 ° C. over 64 minutes (0.5 ° C./minute) with the rotation speed being 280 rpm. Subsequently, after raising the temperature by 1 ° C. over 30 minutes (0.03 ° C./min), the temperature was maintained for 110 minutes, and the volume median diameter (Dv50) was measured using a multisizer to grow to 5.93 μm. The stirring conditions at this time were the same as those in Toner Production Example 7.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously mixed for 6 minutes with the internal temperature of 53.0 ° C and the rotation speed of 280 rpm, and held as it was for 90 minutes. At this time, the Dv50 of the particles was 6.23 μm.

○ Circularization Step Subsequently, the temperature was raised to 85 ° C. while mixing a mixed aqueous solution of 20% DBS aqueous solution (6 parts as solids) and 0.04 part of water over 30 minutes, and then 92 ° C. over 130 minutes. Until the average circularity reached 0.943, heating and stirring were continued under these conditions. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, Dv50 of the particles was 6.17 μm, and the average circularity was 0.945. The washing step and the drying step were performed in the same manner as in Toner Production Example 7.

External Addition Step After adding 7.5 g of Clariant H30TD silica as an external additive to 500 g of the obtained toner base particles I, and mixing with a 9 L Henschel mixer (Mitsui Mining Co., Ltd.) at 3000 rpm for 30 minutes, Maruo Calcium Toner I was obtained by mixing 1.2 g of HAP-05NP calcium phosphate manufactured by Co., Ltd., mixing at 3000 rpm for 10 minutes, and sieving with 200 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured by using the toner I multisizer obtained here is 6.16 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 2.79%, the average circularity was 0.946, and the number variation coefficient was 19.2%.

[Toner Production Example 9]
(Manufacture of toner mother particles J)
In the aggregation process (core material aggregation process, shell coating process), rounding process, washing process and drying process of “manufacturing toner mother particles H”, “core material aggregation process”, “shell coating process” and “rounding process” The toner mother particles J were obtained in the same manner as in “Production of toner mother particles H” in Toner Production Example 7, except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Subsequently, the mixture was stirred at 280 rpm at an internal temperature of 10 ° C. and 0.12 part of a 5% by weight aqueous solution of potassium sulfate was continuously mixed over 1 minute, and then the colorant dispersion H was continuously mixed over 5 minutes. Mix evenly at a temperature of 10 ° C. Thereafter, 0.5 part of demineralized water was continuously mixed for 26 minutes, and then the internal temperature was raised to 52.0 ° C. over 64 minutes (0.5 ° C./minute) while maintaining the rotational speed of 280 rpm. Subsequently, after raising the temperature by 1 ° C. over 30 minutes (0.03 ° C./min), the temperature was maintained for 130 minutes, and the volume median diameter (Dv50) was measured using a multisizer to grow to 6.60 μm. The stirring conditions at this time were the same as those in Toner Production Example 7.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously mixed for 6 minutes with the internal temperature of 53.0 ° C and the rotation speed of 280 rpm, and held as it was for 60 minutes. At this time, the Dv50 of the particles was 6.93 μm.

○ Circularization Step Subsequently, the temperature was raised to 90 ° C. while mixing a mixed aqueous solution of 20% DBS aqueous solution (6 parts as a solid content) and 0.04 part of water over 30 minutes, and then 97 over 60 minutes. The temperature was raised to 0 ° C., and heating and stirring were continued under these conditions until the average circularity reached 0.945. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, the Dv50 of the particles was 6.93 μm and the average circularity was 0.945. The washing step and the drying step were performed in the same manner as in Toner Production Example 7.

External Addition Step To the obtained toner base particles J500 g, 6.25 g of Clariant H30TD silica as an external additive is mixed and mixed with a 9 L Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) for 30 minutes at 3000 rpm. Toner J was obtained by mixing 1.0 g of HAP-05NP calcium phosphate manufactured by Calcium Co., Ltd., mixing at 3000 rpm for 10 minutes, and sieving with 200 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured using the toner J multisizer obtained here is 6.97 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 1.85%, the average circularity was 0.946, and the number variation coefficient was 19.5%.

[Toner Comparative Production Example 2]
(Production of toner mother particles K)
In the aggregation process (core material aggregation process, shell coating process), rounding process, washing process and drying process of “manufacturing toner mother particles H”, “core material aggregation process”, “shell coating process” and “rounding process” The toner base particles K were obtained in the same manner as in “Production of toner base particles H” in Toner Production Example 7, except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Subsequently, the mixture was stirred at 280 rpm at an internal temperature of 10 ° C. and 0.12 part of a 5% by weight aqueous solution of potassium sulfate was continuously mixed over 1 minute, and then the colorant dispersion H was continuously mixed over 5 minutes. Mix evenly at a temperature of 10 ° C. Thereafter, 100 parts of demineralized water was continuously mixed for 30 minutes, and then the internal temperature was raised to 34.0 ° C. over 40 minutes (0.6 ° C./min) with the rotation speed being 280 rpm. Subsequently, it hold | maintained for 20 minutes, the volume median diameter (Dv50) was measured using the multisizer, and it was made to grow to 3.81 micrometers.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was mixed for 6 minutes while maintaining the internal temperature of 34.0 ° C and the rotation speed of 280 rpm, and held as it was for 90 minutes.

○ Circularization process Subsequently, 20% DBS aqueous solution (6 parts as solid content) was mixed for 10 minutes while maintaining the rotation speed at 280 rpm (the same stirring speed as the aggregation process rotation speed), and then 76 ° C. over 30 minutes. The mixture was heated and stirred until the average circularity reached 0.962. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry.

[Production of Toner K]
Thereafter, 100 parts of the toner base particles H of toner production example 7 and 1 part of the toner base particles K are mixed, and 500 g of this toner base particle mixture K is mixed with 8.75 g of Clariant H30TD silica as an external additive. After mixing for 30 minutes at 3000 rpm with a 9 L Henschel mixer (Mitsui Mining Co., Ltd.), 1.4 g of HAP-05NP calcium phosphate manufactured by Maruo Calcium Co., Ltd. is mixed, mixed for 10 minutes at 3000 rpm, and sieved with 200 mesh. Toner K was obtained.

Analyzing Step The “volume median diameter (Dv50)” measured using the toner K multisizer obtained here is 5.31 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 7.22%, the average circularity was 0.949, and the number variation coefficient was 19.2%.

[Toner Comparative Production Example 3]
(Manufacture of toner mother particles L)
In the aggregation process (core material aggregation process, shell coating process), rounding process, washing process and drying process of “manufacturing toner mother particles H”, “core material aggregation process”, “shell coating process” and “rounding process” The toner base particles L were obtained in the same manner as in “Production of toner base particles H” in Toner Production Example 7, except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Then at an internal temperature of 10 ° C., allowed to stir at 310 rpm, 5 minutes of continuous mixing over a period of 1 minute to 0.12 parts of a 5 mass% aqueous solution of potassium sulfate as a _K 2 SO _4, the colorant dispersion H The mixture was continuously mixed and uniformly mixed at an internal temperature of 10 ° C.

  Thereafter, 100 parts of demineralized water was continuously mixed for 30 minutes, and then the internal temperature was raised to 48.0 ° C. over 67 minutes (0.5 ° C./minute) with the rotation speed being 310 rpm. Next, after raising the temperature by 1 ° C. every 30 minutes (0.03 ° C./min), the temperature was maintained at 53.0 ° C., and the volume median diameter (Dv50) was measured using a multisizer and grown to 5.08 μm. .

The stirring conditions at this time were the same as in Toner Production Example 7 except for the following (c).
(C) The peripheral speed at the tip of the stirring blade: 310 rpm, that is, 3.08 m / sec.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously mixed for 6 minutes with the internal temperature of 54.0 ° C and the rotation speed of 310 rpm, and held as it was for 60 minutes. At this time, the Dv50 of the particles was 5.19 μm.

○ Circularization Step Subsequently, the temperature was raised to 83 ° C. while mixing a mixed aqueous solution of 20% DBS aqueous solution (6 parts as a solid content) and 0.04 part of water over 30 minutes, and thereafter 1 every 30 minutes. The temperature was raised to 90 ° C., and heating and stirring were continued under these conditions until the average circularity reached 0.939 over 2.5 hours. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, the Dv50 of the particles was 5.18 μm and the average circularity was 0.940. The washing step and the drying step were performed in the same manner as in Toner Production Example 7.

External Addition Step To the obtained toner base particle L500 g, 8.75 g of Clariant H30TD silica as an external additive is mixed and mixed with a 9 L Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) at 3000 rpm for 30 minutes. Toner L was obtained by mixing 1.4 g of HAP-05NP calcium phosphate manufactured by Calcium Co., Ltd., mixing at 3000 rpm for 10 minutes, and sieving with 200 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured using the multi-sizer of toner L obtained here is 5.18 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 9.94%, the average circularity was 0.940, and the number variation coefficient was 20.4%.

[Toner Comparative Production Example 4]
(Manufacture of toner mother particles M)
In the aggregation process (core material aggregation process, shell coating process), rounding process, washing process and drying process of “manufacturing toner mother particles H”, “core material aggregation process”, “shell coating process” and “rounding process” The toner mother particles M were obtained in the same manner as in “Production of toner mother particles H” in Toner Production Example 7, except that “” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Then at an internal temperature of 10 ° C., was allowed to stir 0.12 parts of a 5% by weight aqueous solution as _K 2 SO ₄ potassium sulfate from continuously mixed for 1 minute at 310 rpm, over a period of 5 minutes colorant dispersion H And mixed uniformly at an internal temperature of 10 ° C.

  Thereafter, 100 parts of demineralized water was continuously mixed for 30 minutes, and then the internal temperature was raised to 52.0 ° C. over 56 minutes (0.8 ° C./min) while maintaining the rotation speed of 310 rpm. Next, after raising the temperature by 1 ° C. every 30 minutes (0.03 ° C./min), hold at 54.0 ° C., measure the volume median diameter (Dv50) using a multisizer, and grow it to 5.96 μm. It was.

The stirring conditions at this time were the same as in Toner Production Example 7 except for the following (c).
(C) The peripheral speed at the tip of the stirring blade: 310 rpm, that is, 3.08 m / sec.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously mixed for 6 minutes with the internal temperature of 54.0 ° C and the rotation speed of 310 rpm, and held as it was for 60 minutes. At this time, Dv50 of the particles was 5.94 μm.

○ Circularization Step Subsequently, the mixture was heated to 88 ° C. while mixing a mixed aqueous solution of 20% DBS aqueous solution (6 parts as a solid content) and 0.04 part of water over 30 minutes, and thereafter 1 every 30 minutes. The temperature was raised to 90 ° C., and heating and stirring were continued under these conditions until the average circularity reached 0.940 over 2 hours. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, the Dv50 of the particles was 5.88 μm and the average circularity was 0.943. The washing step and the drying step were performed in the same manner as in Toner Production Example 7.

External Addition Step To the obtained toner base particles M500 g, 7.5 g of Clariant H30TD silica as an external additive is mixed and mixed with a 9 L Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) for 30 minutes at 3000 rpm. Toner M was obtained by mixing 1.2 g of HAP-05NP calcium phosphate manufactured by Calcium Co., Ltd., mixing at 3000 rpm for 10 minutes, and sieving with 200 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured using a multisizer of the toner M obtained here is 5.92 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 5.22%, the average circularity was 0.945, and the number variation coefficient was 21.2%.

[Toner Comparative Production Example 5]
3 parts of toner base particles K are mixed with 100 parts of toner base particles J of toner production example 9, 500 g of this toner base particle mixture is mixed with 6.25 g of H30TD silica manufactured by Clariant as an external additive, and a 9 L Henschel mixer is mixed. (Mitsui Mining Co., Ltd.) was mixed at 3000 rpm for 30 minutes, Maruo Calcium Co., Ltd. HAP-05NP calcium phosphate 1.0 g was mixed, mixed at 3000 rpm for 10 minutes, and sieved with 200 mesh to obtain toner N. .

Analyzing Step The “volume median diameter (Dv50)” measured using the toner N multisizer obtained here is 6.88 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 9.08%, the average circularity was 0.952, and the number variation coefficient was 25.6%.

[Live-action evaluation]
A small spot irradiation type blue LED (Nisshin Denshi, B3MP-8: 470 nm) is used as a photoconductor for the exposure part of a commercial tandem LED color printer MICROLINE Pro 9800PS-E (Oki Data Co., Ltd.) that supports A3 printing. It was modified so that it could be irradiated. Except that the total length of the aluminum cylinder used for the photoconductors E11 to E15 and the comparative photoconductors P4 to P6 is changed to a total length suitable for the printer in the black drum cartridge and the black toner cartridge of the modified machine. A photoconductor and toner produced in the same manner were mounted, and the cartridge was mounted on the printer.

Specifications of MICROLINE Pro 9800PS-E:
Quadruple tandem color 36ppm, monochrome 40ppm
Contact roller charging (DC voltage applied)
With static elimination light

A strobe illumination power source LPS-203K was connected to the small spot irradiation type blue LED of this image forming apparatus, and black dots having a diameter of 8 mm were written at intervals of 8 mm to form an image.
The obtained point image was enlarged, and the image quality was evaluated in five stages by combining the sharpness of the developed point image outline and the degree of toner scattering around the point image. The results are shown in Table 9 and Table 10.

The criteria for comprehensive evaluation of image quality based on the sharpness of the outline of the point image and the degree of scattering around the point image were as follows.
1: The dot outline is clear and a good dot image is obtained without toner scattering. 2: The dot image is good without toner scattering.
3: A good dot image is obtained although the toner is slightly scattered.
4: There is toner scattering and the sharpness of the outline of the point image is low.
5: Toner scattering is large and the contour of the dot image is uneven.

  Live-action evaluation is shown below.

  For toners L and N, the toner ejected from the developing tank, and the actual image evaluation could not be performed.

  From the above results, when the electrophotographic photosensitive member of the present invention and the toner are used, and monochromatic light having a wavelength of 380 nm to 500 nm is used as the exposure light source, a high-quality image that is particularly faithful to the electrostatic latent image can be obtained. It became clear.

  Since the photoconductor of the present invention has high sensitivity and high image quality with respect to a light source having a wavelength of 380 nm or more and 500 nm or less, an image forming apparatus equipped with the photoconductor and an electrophotographic cartridge can be arbitrarily used in an electrophotographic system. In particular, it can be suitably used for printers, facsimiles, copiers, and the like.

1 is a schematic diagram illustrating a main configuration of an embodiment of an image forming apparatus including an electrophotographic photoreceptor and toner according to the present invention. It is a 1000 times SEM photograph showing the adhesion state of the toner on the cleaning blade after evaluation of the actual image of the toner.

Explanation of symbols

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

Claims (10)

An electrophotographic photosensitive member; a charging unit that charges the electrophotographic photosensitive member; an exposing unit that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image; An image forming apparatus comprising at least a developing unit that develops a latent image with the toner and a transfer unit that transfers the toner to a transfer target,
The electrophotographic photoreceptor has a photosensitive layer containing a compound represented by the following formula (1),
An image forming apparatus, wherein an electrostatic latent image is formed by exposing the electrophotographic photosensitive member with monochromatic light having a wavelength of 380 nm to 500 nm.
(In the formula (1),
Ar ¹ and Ar ² each independently represent an arylene group which may have a substituent, X represents a linking group having 3 to 25 atoms,
n ¹ represents an integer of 0 or 1,
Cp ₁ represents a C 50 or less organic group having a hydroxyl group and having a structure represented by any one or more of the following formulas (3) to (6):
Z1 represents a divalent aromatic hydrocarbon group or nitrogen-containing heterocyclic group which may have a substituent,
Rn represents a substituent having 2 to 20 atoms.
Ar ¹ and Ar ² may be cross-linked with each other. )
(In the formulas (3) to (6), Z1 and Rn represent the same as Z1 and Rn in the formula (1). Z2 and Z3 each independently have 30 or less carbon atoms having a ring structure. Z4 represents an organic group having at least one OH group and having a ring structure and having 30 or less carbon atoms, wherein R ² , R ³ and R ⁴ each independently represent a halogen atom, a hydrogen atom , nitrile group, or may have a substituent, .n ² representing the one selected from the group consisting of alkyl group, aryl group and alkoxy group represents an integer of 0 or 1.) 2. The image forming apparatus according to claim 1, wherein the toner has an average circularity measured by a flow-type particle image analyzer of 0.940 or more and 1.000 or less. The image forming apparatus according to claim 1, wherein the toner satisfies all of the following (i) to (iii):
(I) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 μm or less.
(Ii) The average circularity is 0.93 or more.
(Iii) The relationship between the volume median diameter (Dv50) of the toner and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50). Fulfill. In the toner, the relationship between the volume median diameter (Dv50) and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies the following formula (iii-1): The image forming apparatus according to claim 3 .
In the toner, the relationship between the volume median diameter (Dv50) and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies the following formula (iii-2): The image forming apparatus according to claim 3 or 4 .
The toner is characterized in that it is a toner produced in a wet medium, the image forming apparatus according to any one of claims 1-5. The toner is characterized by having a resin coating layer, an image forming apparatus according to any one of claims 1-6. A cartridge case for detachably supporting the electrophotographic photosensitive member with respect to the image forming apparatus according to claim 1 ;
An electrophotographic cartridge comprising the electrophotographic photosensitive member. 9. The electrophotographic cartridge according to claim 8 , wherein an average circularity measured by the toner flow type particle image analyzer is 0.940 or more and 1.000 or less. 9. The electrophotographic cartridge according to claim 8 , wherein the toner satisfies all of the following (i) to (iii).
(I) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 μm or less.
(Ii) The average circularity is 0.93 or more.
(Iii) The relationship between the volume median diameter (Dv50) of the toner and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50). Fulfill.