JPH1010764A - Electrifying member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent electrification fault in a low temp. and low humidity environment and to prevent the occurrence of pinhole leak in a high temp. and high humidity environment by incorporating a polymer charge transfer-type bonded compd. comprising a specified semipolar polymer compd. with addition of a tertiary amine into a conductive layer. SOLUTION: As for the polymer charge transfer-type bonded compd., a charge transfer complex expressed by formula III is used, and the complex is prepared by the reaction of a semipolar org. boron polymer compd. expressed by formula I and a tertiary amine expressed by formula II. The ratio of boron atoms to nitrogen atoms in the complex is specified to 1:1. In the formulae, A is a substituent expressed by -(X)k-(Y)l-(Z)m-, (n) represents the polymn. degree, X and Y are oxygen-contg. hydrocarbon groups having <=100 carbon atoms and having ether residues as the end groups, Y is -OC-R1 -CO-O or -OCHN-R2 -NHCO-O-, (k), (l), (m) are integers 0 or 1, R1 is a hydrocarbon group having 1 to 82 carbon atoms, R2 is a hydrocarbon group having 2 to 13 carbon atoms, and R3 to R5 are hydrocarbon groups each having one or more hydroxyl groups or ether residues.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrophotographic copying machine,
The present invention relates to a charging member in an image forming apparatus such as an electrophotographic apparatus such as a laser printer, a facsimile, or a composite OA apparatus thereof, or an electrostatic recording apparatus. More specifically, the present invention relates to a charging member that presses a surface of a charged body such as a photoconductor or a dielectric to uniformly charge the surface of the charged body.

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrophotographic apparatus or an electrostatic recording apparatus, a surface of an object to be charged such as a photoconductor or a dielectric is charged. As the charging processing means, a non-contact charging method is generally employed in which charging is performed by corona discharge generated by applying a high voltage to a tungsten wire. However, in this non-contact charging system, a large amount of ozone and nitrogen oxide (NOx) is generated, causing environmental pollution around the image forming apparatus. In addition, the corona product deteriorates the surface of the photoreceptor, causing deterioration of the photoreceptor and blurring of the image, and contamination of the wire affects the image quality, resulting in image white spots and black streaks. Was. In contrast to the non-contact charging method, there is a contact charging method in which a charging member is brought into contact with a member to be charged to perform a charging process. This contact charging method has the advantage that the voltage applied to the charging member is low and the amount of generated ozone is very small.

[0003] As a contact-type charging member, those having a roll-shaped, blade-shaped, or belt-shaped structure are known. For example,
As exemplified in JP-A-63-149669, a single-layer structure in which a core metal is coated with a foamed urethane rubber layer dispersed with carbon black, or an elastic material such as EPDM or acrylonitrile-butadiene rubber (NBR) is used for the core metal. Various roll members having a two-layer structure in which a rubber layer is formed and a carbon black-dispersed urethane rubber layer is coated thereon are known. As described above, a conductive elastic roll obtained by kneading a rubber material obtained by kneading a conductive agent such as carbon black around a core metal and vulcanizing and molding it is widely used because a sufficient charge amount can be obtained. Also, many proposals have been made as to what range of adjusting the electric resistance value of the roll and the coating layer to obtain an effective charge amount. By the way, in a case where a pinhole is present on the surface of the member to be charged and a conductive drum such as aluminum is exposed, when a charging process is performed using the above-mentioned roll member, a large current suddenly flows through the pinhole portion. As a result, the roll member is instantaneously destroyed. At the same time, the charged portion of the member to be contacted with the roll member is charged poorly, so that a linear black stripe is generated on the copy sheet. This phenomenon is called pinhole leak, and many countermeasures have been conventionally proposed.

[0004] For example, Japanese Patent Application Laid-Open No. 1-142569 discloses an epichlorohydrin-ethylene oxide copolymer rubber (EC) having the lowest electric resistance as a general-purpose polymer material.
A conductive roll has been proposed in which a conductive layer made of O) having a volume resistivity × thickness of 10 ⁵ to 10 ⁷ Ωcm ² is coated on a conductive elastic layer. The conductive roll is said to have a uniform electric resistance of the copolymer rubber and a small humidity dependency, so that the resistance is small even at a low temperature and a low humidity, and is excellent in leak resistance (dielectric breakdown resistance). In addition, Japanese Unexamined Patent Application Publication No.
198470 proposes a semiconductive roll in which a polymer compound having an ether bond in a repeating unit contains perchlorate. This semiconductive roll is
The perchlorate is coordinated to the oxygen atom that contributes to the ether bond, so that the increase in resistance is small even in a low humidity environment. Japanese Patent Application Laid-Open No. 7-28301 discloses a base layer having a volume resistivity of 10 ⁶ to 10 ⁸ Ωcm formed of an ionic conductive foam to which quaternary ammonium or perchlorate is added, and a protective layer provided thereon. Conductive rolls have been proposed. According to this conductive roll, since the base layer itself has a medium resistance, the allowable range of voltage application is widened, and image defects are prevented.

[0005]

However, the ECO
The conductive roll disclosed in the former publication, coated with, still has a large environmental dependence of electric resistance. For this reason, there is a difference in charging performance due to a change in the environment. The charging voltage is low in a low-temperature and low-humidity environment, and pinhole leak is likely to occur in a high-temperature and high-humidity environment. In particular, there is a problem that the resistance layer cannot perform its original function in a low-temperature and low-humidity environment. Further, in each of the conductive rolls disclosed in the latter publication, the electric resistance of the roll is reduced due to the coordination of an ionic conductive agent such as perchlorate. Therefore, although the charging failure in a low-temperature and low-humidity environment is eliminated, a pinhole leak in a high-temperature and high-humidity environment is more likely to occur. That is, there is a problem that the basic functions of charging performance and preventing dielectric breakdown cannot be compatible. Therefore, an object of the present invention is to solve the above-mentioned problems, and the electric resistance is less dependent on the environment, and a charging failure does not occur under low temperature and low humidity, and a pinhole does not occur even under high temperature and high humidity. An object of the present invention is to provide a high-quality charging member in which no leakage is observed.

[0006]

Means for Solving the Problems In view of the current state of the art in the field of charging members, the present inventors have conducted intensive studies and studies in order to realize a charging member having less environmental dependence of electrical resistance. The charge performance of the charging member by including a polymer charge transfer conjugate in which a tertiary amine is added to a semipolar polymer compound in which a boron atom bonded to four oxygen atoms is a spiro atom in the conductive layer. The present invention has been found to be compatible with the present invention and the leak resistance. That is, the charging member of the present invention is composed of at least a conductive substrate and a conductive layer containing a polymer charge transfer type conjugate formed thereon, and the polymer charge transfer type conjugate described below. Represented by the following general formula (III) obtained by reacting a semipolar organic boron polymer compound represented by the following general formula (I) with a tertiary amine represented by the following general formula (II) A charge transfer complex is used, and the atomic ratio of boron atoms to nitrogen atoms in the charge transfer complex is 1: 1.

Embedded image [Wherein, A is a substituent represented by-(X) k- (Y) 1- (Z) m-, and n means the degree of polymerization. Here, X and Z are
May be the same or different, and represent an oxygen atom-containing hydrocarbon group having a total of 100 or less carbon atoms having an ether residue at the terminal, and Y represents -OC-R ₁ -CO-O- group or -OCHN-R _{A 2-} NHCO-O- group (provided that
R ₁ represents a hydrocarbon group having ₁ to 82 carbon atoms, R ₂ represents a hydrocarbon group having ₂ to 13 carbon atoms), and k, l, and m each represent an integer of 0 or 1. ]

Embedded image (Wherein R ₃ , R ₄ and R ₅ may be the same or different and each represents a hydrocarbon group which may contain one or more hydroxyl groups or ether residues,
The total carbon number of R ₃ , R ₄ and R ₅ is 82 or less, and at least one of them has one or more hydroxyl groups. )

Embedded image (In the formula, A, n, R ₃ , R ₄ and R ₅ are as defined above.)

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
When the charging member of the present invention is used as a charging roll,
As shown in FIGS. 1A and 1B, a conductive elastic layer 1b is fixed to the outer peripheral surface of the conductive substrate 1a, and has a two-layer structure in which a surface layer 1c is coated on the elastic layer 1b. Further, FIG. 2A,
As shown in B, the outer peripheral surface of the conductive substrate 2a is successively formed with the conductive rubber layer 2b, the bleed prevention layer 2c, the resistance layer 2d, and the surface layer 2.
e) and has a four-layer structure. Here, the conductive elastic layer 1b having a two-layer structure, the conductive rubber layer 2b having a four-layer structure, the bleed prevention layer 2c, and the resistance layer 2d each correspond to a “conductive layer” in the present invention. Also, the bleed prevention layer 2c is not always a necessary layer. In the case of a three-layer structure in which this layer is unnecessary, a layer structure in which the lower layer of the conductive elastic layer 1b is a rubber layer 2b and the upper layer is a resistance layer 2d. Is equivalent to
There is no need to demarcate the boundaries of both layers. Further, the surface layers 1c and 2e may be formed as needed. Therefore, the charging member of the present invention can adopt a layer configuration of one to four layers. The conductive substrates (1a, 2a)
It functions as an electrode and support member of the charging member,
For example, aluminum or copper alloy, metal or alloy such as stainless steel, chromium, nickel plated iron,
It is made of a solid cylindrical or hollow cylindrical conductive material such as a synthetic resin. The outer diameter of the conductive substrate is usually 4 to 12 m
m.

First, the charging member (1) having a two-layer structure will be described in detail. The conductive elastic material layer (1b) has a predetermined resistance value and a predetermined hardness so that the charging member can be uniformly charged by pressing against the surface of the charging member with an appropriate nip width or nip pressure. It is provided to fit in.
This elastic layer is formed by including a conductive agent and a polymer charge transfer type conjugate (hereinafter, referred to as a charge transfer type conjugate) in a rubber material. Examples of the rubber material include epichlorohydrin rubber (CO), ECO, epichlorohydrin rubber such as epichlorohydrin-allyl glycidyl ether copolymer, and ethyl polyacrylate, polybutyl acrylate, polyacrylate methoxyethyl, ethyl acrylate-acrylonitrile copolymer. Highly polar rubbers such as various acrylic rubbers represented by polymers and the like, and blended rubbers thereof are suitable. The volume resistivity of the conductive elastic layer is preferably in the range of 10 ⁷ to 10 ¹⁰ Ωcm. The volume specific resistance value is adjusted by blending a charge transfer type binder described later in a rubber material, but a conductive agent may be used in combination as needed. Examples of the conductive agent include various conductive metals or alloys such as carbon black, graphite, aluminum, copper, nickel, and stainless steel, tin oxide, indium oxide, titanium oxide, zinc oxide, and tin oxide.
Various conductive metal oxides such as antimony oxide solid solution and tin oxide-indium oxide solid solution, and fine powders such as those obtained by subjecting the surface of an insulating material to a conductive treatment can be used. Also,
The thickness of the conductive elastic layer may be in the range of 1 to 5 mm, and is preferably in the range of 2 to 4 mm. When the thickness of the elastic layer is less than 1 mm, the elastic layer is affected by the conductive substrate, and the nip uniformity is impaired. On the other hand, when the thickness is more than 5 mm, not only does the material cost increase, but also the device becomes larger.

In order to improve the reliability of the device, it is preferable to cover the conductive elastic layer with the surface layer (1c). The surface layer functions as a protective layer that prevents contamination of the charging member due to adhesion or fixation of toner or paper powder remaining on the surface of the member to be charged, and prevents deterioration in charging performance and occurrence of image quality defects due to the charging performance. . Further, it is provided in order to prevent a compounding agent such as a liquid charge transfer type binder from oozing out from the inside of the conductive elastic layer to the surface and contaminating the surface of the charged body. This surface layer is preferably made of a highly polar polymer material such as a polyamide resin or a polyurethane resin. As the polyamide resin, an amorphous resin called water-soluble nylon or alcohol-soluble nylon is preferably used. For example, AQ nylon A-7 sold by Toray Industries, Inc.
Water-soluble modified polyamide resins such as 0, A-90, P-70, and Amilan CM-4000, CM-4001, CM
-8000, CM-831, CM-833, CM-84
And alcohol-soluble copolymerized nylons such as No. 2.
Further, Tresin EF-30T and Tresin G-550 (manufactured by Teikoku Chemical Co., Ltd.) in which the amide group is N-methoxymethylated,
Luckmide 5003 (manufactured by Dainippon Ink), T-8 nylon (manufactured by Unitika) and the like are also suitable. Since these polyamide resins are soluble in a solvent, they are suitable for forming a coating film by a coating method. In the case of N-methoxymethylated polyamide, the polyamide itself may be crosslinked by a dealcoholization reaction in the presence of a catalyst such as succinic acid, lauric acid, crotonic acid, glutaric acid, and lactic acid.

The above polyurethane resin is generally obtained by reacting an organic polyisocyanate with a long-chain polyol and, if necessary, a chain extender. As organic polyisocyanates, tetramethylene diisocyanate, hexamethylene diisocyanate, 3-methyl-
Aliphatic diisocyanates such as 1,5-pentane diisocyanate and lysine diisocyanate, alicyclic diisocyanates such as isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tetramethyl xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, m -Phenylene diisocyanate, p-phenylene diisocyanate, 2,
4-tolylene diisocyanate, 2,6-tolylene diisocyanate, m-xylylene diisocyanate, p-
Xylylene diisocyanate, diphenyl-4,4'-
Diisocyanate, 2-nitrodiphenyl-4,4'-
Diisocyanate, 3,3'-dimethoxydiphenyl-
4,4'-diisocyanate, diphenylmethane-2,
4'-diisocyanate, diphenylmethane-4,4 '
-Diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, β, β-diphenylpropane-4,4'-diisocyanate, diphenylether-4,4'-diisocyanate, 1,4-naphthylene diisocyanate, Aromatic diisocyanates such as 1,5-naphthylene diisocyanate; polyol adducts such as trimethylolpropane; and prepolymers of a polyisocyanate having a terminal isocyanate group and a polyol, and the like.

The long-chain polyols include a) polyester polyols, b) polycarbonate polyols, c) polyether polyols, and copolymerized polyols thereof. a) Polyester polyols include polyester polyols and polyester amide polyols obtained by a condensation reaction of a dibasic acid or a reactive acid derivative thereof such as an ester, an acid halide or an acid anhydride with a glycol or an amino alcohol alone or in a mixture. is there. Examples of the dibasic acid include dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid, phthalic acid, isophthalic acid, terephthalic acid, hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid, and naphthalenedicarboxylic acid. And their reactive acid derivatives. Examples of the glycol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,5-pentanediol, neopentylene glycol, and 1,6-hexanediol. , 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, triethylene glycol,
Examples include dipropylene glycol, 1,4-cyclohexanedimethanol, and ethylene oxide or propylene oxide adducts of bisphenol A, which are used in a stoichiometric excess relative to the dibasic acid or its reactive derivative. Examples of the amino alcohol include ethanolamine, propanolamine, and ε-aminohexanol. Further, a part of the above glycol can be substituted with a diamine such as hexamethylenediamine, isophoronediamine, xylylenediamine and the like. further,
Lactone-based polyester polyols obtained by ring-opening polymerization of lactone monomers such as ε-caprolactone are also included.

B) The polycarbonate polyol is generally obtained by a dealcoholation reaction between a polyhydric alcohol and ethylene carbonate, dimethyl carbonate, diethyl carbonate, diphenyl carbonate or the like.
Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, 1,3-propanediol,
2-butanediol, 1,4-butanediol, 1,5
-Pentanediol, neopentylene glycol, 1,
For example, 6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, 1,4-cyclohexanedimethanol, or the like, or a mixture thereof is used.

C) Polyether polyols include polyethylene glycol, polypropylene glycol, polytetramethylene ether, etc., obtained by ring-opening polymerization of ethylene oxide, propylene oxide, tetrahydrofuran, etc .; And a polyester ether polyol having a copolymer component. These long-chain polyols a) to c) can be used alone or as a mixture of two or more compounds.

The chain extender is generally a compound having a molecular weight of 300 or less and having two or more active hydrogens in a molecule, and polyols, polyamines, amino alcohols and the like are used. Specifically, for example, ethylene glycol, 1,2
-Propylene glycol, 1,3-propanediol,
1,2-butanediol, 1,4-butanediol,
1,5-pentanediol, neopentylene glycol, 1,6-hexanediol, 3-methyl-1,5-
Pentanediol, 1,8-octanediol, 1,9
-Polyols such as nonanediol, diethylene glycol, triethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol, bishydroxyethoxybenzene, ethylene oxide or propylene oxide adducts of bisphenol A, glycerin, trimethylolpropane; hexamethylenediamine ,
Isophoronediamine, xylylenediamine, methylene-
Polyamines such as bis (chloroaniline); amino alcohols such as ethanolamine, propanolamine and ε-aminohexanol. In addition, water and urea can also be used as chain extenders. If the total number of moles of the chain extender is larger than the number of moles of the long-chain polyol, the ratio of urethane bonds having strong cohesive force increases, and the ratio of hard segments in the polyurethane increases. Therefore, when a chain extender is used, the number of moles thereof is preferably not more than a total of several moles of the long-chain polyol, particularly preferably not more than ２.

In general, it is possible to form a coating only with a linear polymer which is a reaction product of a polyether polyol and a polyisocyanate. The film can be formed by thermosetting to a degree. As the above polymer, high urethane No. 2000, No. 500
0 (manufactured by NOF CORPORATION), Nipporan 125,800,1
100 (manufactured by Nippon Polyurethane). Further, when the fluororesin-modified polymer is used, surface contamination of the charging member can be avoided. That is, Campeflon HD (manufactured by Kansai Paint Co., Ltd.), Lumiflon series (manufactured by Asahi Glass Co., Ltd.)
Also, a coating film having a crosslinked structure obtained by reacting a polyol-added polyisocyanate compound such as a trimethylolpropane adduct of hexamethylene diisocyanate and a trimethylolpropane adduct of tolylene diisocyanate, or a polyamino resin is preferable. The surface layer is adjusted to have the same volume resistivity as the conductive elastic layer by dispersing the conductive agent. The thickness of the surface layer is in the range of 5 to 50 μm, and even 10
It is preferably in the range of ４０40 μm. Film thickness 5μm
If the thickness is smaller, the charging member may be worn over a long period of use. If the thickness is more than 50 μm, the hardness of the charging member increases more than necessary.

Next, the charging member (2) having a four-layer structure will be described in detail. The conductive rubber layer (2b) is provided to keep the charging member at a predetermined hardness so that the charging member forms an appropriate nip and uniformly charges the surface of the member to be charged.
Examples of the rubber material include isoprene rubber, chloroprene rubber, epichlorohydrin rubber, norbornene rubber, butyl rubber, urethane rubber, silicone rubber, fluorine rubber, SBR, NBR, EPDM, acrylic rubber, acrylonitrile-butadiene-styrene rubber, and blended rubbers thereof. Is mentioned. These rubber materials may be foamed or non-foamed. The conductive agent is dispersed in this rubber layer to have a volume resistivity value of 10 ^8.
Ωcm or less and the hardness is adjusted to 20 to 80 ° according to JIS A. The former volume resistivity is a necessary requirement for supplying power to the resistance layer and the surface layer. The latter hardness is a requirement necessary for uniform nip of the charging member due to pressing against the member to be charged. The thickness of the rubber layer may be in the range of 1 to 5 mm as in the case of the conductive elastic layer. Since the rubber material itself has a volume resistivity value of 10 ⁹ Ωcm or more, usually 10 ¹² Ωcm or more, carbon black is exclusively used as the conductive agent in terms of inexpensiveness. Since carbon black has a strong reinforcing property, it is necessary to balance resistance and hardness. At this time, the optimum range of the conductivity and the rubber hardness differs depending on the requirements of the member to be charged, the charging system, and the like. Therefore, a design suitable for the system is required.
Urethane rubber and silicone rubber are particularly suitable for achieving both the above-described conductivity and rubber hardness. The hardness of the charging member can be reduced without blending a softening agent such as a process oil or a plasticizer.

When the conductive rubber layer is made of a rubber material other than urethane rubber, silicone rubber or foamed rubber, the above softener is blended into the rubber material to independently control conductivity and rubber hardness. This is also an effective means.
In this case, it is preferable to provide an anti-bleeding layer (2c) on the rubber layer because the softening agent oozes out and contaminates the surface of the member to be charged. The bleed prevention layer is preferably made of the same polyamide resin, polyurethane resin or the like as the surface layer (1c). Among them, N-methoxymethylated polyamide resin is preferable. A conductive agent is appropriately blended in the bleed prevention layer. The film thickness is not particularly limited, but may be usually in the range of 5 to 50 μm.

The resistance layer (2d) is provided for adjusting the charging member to a predetermined volume specific resistance value, and is composed of a thin film containing a charge-transfer type binder described later in a polymer material. . The polymer material is not particularly limited as long as it is a polymer such as rubber, but it is desirable that the polymer material has good flexibility and flexibility and good followability to the conductive rubber layer. In this sense, among the rubber materials constituting the rubber layer, rubber materials having a polar group in the molecule and having a volume specific resistance in the range of 10 ¹⁰ to 10 ¹² Ωcm, such as the above-mentioned epichlorohydrin rubber and acrylic rubber, are particularly preferred. It is suitable. These rubber materials have a resistance value that is too high and deviates from a preferable resistance region of the charging member. However, by adding a charge transfer type coupling member, the resistance value can be adjusted to an appropriate resistance region of 10 ⁸ to 10 ⁹ Ωcm. Can be. The addition amount of the charge transfer type conjugate was 2 parts per 100 parts by weight of the polymer material.
It is preferably in the range of from 50 to 50 parts by weight, especially from 5 to 20 parts by weight. If the amount of the charge transfer type conjugate is less than 2 parts by weight, the volume resistivity of the resistance layer cannot be reduced to 10 ⁹ Ωcm or less. On the other hand, if the addition amount is more than 50 parts by weight, not only does the cost of the charging member increase, but also there is a concern that the charge transfer type conjugate may phase-separate from the polymer material and bleed out. Actually, when the amount of addition is in the range of 5 to 20 parts by weight, the volume resistivity of the resistive layer is constant in the range of 10 ⁸ to 10 ⁹ Ωcm, and this range is preferable from the viewpoint of the stability of the charging member product. The thickness of the resistance layer is 20 μm or more.
It is adjusted to a range of 1 mm. If the film thickness is smaller than 20 μm, the withstand voltage is low and the leak is likely to occur. The higher the film thickness, the higher the breakdown voltage can be secured. However, since the charge transfer type coupling is a relatively expensive material, the thickness of the resistance layer should be adjusted to a range of 100 to 500 μm. Is desirable. That is, if the film thickness is in this range, there is no possibility that image defects or dielectric breakdown will occur.

The charge transfer type conjugate of the present invention has good solubility in various rubber materials such as a polymer material constituting the resistance layer. Therefore, if the polymer material is thermoset, there is no danger of contaminating the surface of the charged body even if the surface layer is not coated, but under severe conditions, the charge transfer type conjugate may ooze onto the surface. There is. When the surface of the member to be charged is contaminated, for example, the surface resistance of the photoreceptor is reduced and a slight image flow occurs. Therefore, in order to prevent the toner filming and the surface contamination of the member to be charged, it is desirable to coat the surface layer (2e) on the resistance layer in order to enhance the reliability of the image forming apparatus. This surface layer is preferably made of the same polymer material as the surface layer (1c) in the case of a two-layer structure, such as a polyamide resin or a polyurethane resin. The charge transfer conjugate has a very high polarity, as is clear from the chemical structure of the charge transfer complex represented by the general formula (III). The same applies to the surface layer (1c), except that the resistance layer (2d) of the charge transfer type combination or the conductive elastic layer
Bleed-out from (1b) can be effectively prevented because
This is also a high-polarity polymer material. The reason why these polymer materials exhibit the bleeding prevention effect is presumed to be the fact that a very dense network structure is substantially formed by the interaction of strong intermolecular hydrogen bonds derived from amide groups and urethane groups. Is done.

Next, the charge transfer type conjugate according to the present invention will be described. The charge transfer complex represented by the general formula (III) is formed by reacting a semipolar organoboron polymer compound represented by the general formula (I) with a tertiary amine represented by the general formula (II). Wherein the atomic ratio of boron atoms to nitrogen atoms in the reaction product is 1: 1. Here, the atomic ratio refers to the ratio between the boron atom in the organic boron polymer compound and the nitrogen atom in the tertiary amine. Further, the organic boron polymer compound and the tertiary amine may be used alone or as a mixture of two or more. The charge-transfer conjugate has 1 in the molecule.
It is a polymer compound containing the charge transfer complex structure of No. 1 and having a specific volume resistivity of about 10 ⁷ Ωcm at room temperature and exhibiting electron conductivity. Furthermore, because of the inclusion of various functional groups in the molecule, the compatibility with various polymer materials is good, and the polymer is dissolved molecularly in highly polar polymer materials such as epichlorohydrin rubber and acrylic rubber. It is presumed that it is.

The charge transfer conjugate represented by the general formula (III) in the present invention can be synthesized as follows. First, the semipolar organoboron polymer compound represented by the general formula (I) is synthesized as follows. a) Bisglycerin derivative 1 represented by the following general formula (IV)
The mol is reacted with 1 mol of boric acid or its triester or 0.5 mol of boric anhydride (B ₂ O ₃ ) to polyesterify or exchange polyester.

Embedded image (Where A is as defined above)

B) One kind of a diglycerin borate represented by the following general formula (V) or a cyclic boron compound having a total carbon number of 206 or less and containing a diglycerin borate residue represented by the following general formula (VI) or About 2 or more types are subjected to a polyetherification reaction to undergo condensation polymerization.

Embedded image

Embedded image (In the formula, A is as defined above.) Alternatively, the above general formula (V) or (VI) (provided that the substituent is represented by-(X) k- (Y) l- (Z) m-) In the following A, k is 1, and l and m are 0. That is, A represents an oxygen atom-containing hydrocarbon group having a terminal ether residue.
Means 1) or a total of 1 mol of at least two diols represented by formula (I) and a dicarboxylic acid having 3 to 84 carbon atoms,
The ester, the acid halide or the diisocyanate compound having 4 to 15 carbon atoms is reacted with 1 mol or a total of 1 mol thereof to form a polyester or a polyurethane.

The organoboron polymer compound (I) synthesized in this manner comprises a tertiary amine represented by the above (II) having at least one hydroxyl group and an atom of a boron atom and a nitrogen atom. Further reaction is performed at a ratio of 1: 1.
This reaction is carried out at 20 to 200 ° C, preferably 50 to 150 ° C under normal pressure by charging the organoboron polymer compound (I) and the tertiary amine (II) in a sealed or open type reaction vessel. At this time, when an organic solvent such as alcohol, ether, and ketone coexists, the reaction proceeds more easily. As described above, the charge transfer conjugate of the present invention is synthesized. Here, an acidic proton generated when an ion pair is formed in each segment by binding a semipolar bond portion of the organic boron polymer compound (I) and a basic nitrogen of the tertiary amine (II) is formed. , A resonance structure that binds to both the boron atom side and the nitrogen atom side.

The bisglycerin derivative (IV), which is a raw material for synthesizing the semipolar organoboron polymer compound (I), includes, for example, mono- or polyoxyethylene bisglycerin ether, mono- or polyoxyisopropylene bisglycerin ether, Glycerin malonate, bisglycerin maleate, bisglycerin adipate, bisglycerin dodecane dicarbonate, bisglycerin terephthalate, bisglycerin tolylene dicarbamate,
Bisglycerin methylene bis (p-phenylcarbamate), monoether monoester of two molecules of glycerin and one molecule of adipic acid monopolyoxyethylene ester, glycerin and bispolyoxyethylene malonate (ethylene oxide adduct of malonic acid) Diether of glycerin and bispolyoxyethylene adipate, polyoxyethylene-polyoxyisopropylene bisglycerin ether, polyoxyethylene-di (oxymethylene) -polyoxyisopropylene bisglycerin ether, and the like.

The cyclic boron compound represented by the general formula (VI) also includes a compound in which the above bisglycerin fragment is substituted with a diglycerin borate residue.
As these bisglycerin derivatives (IV) and cyclic boron compounds (VI), those having a total carbon number of 206 or less are used.
Dicarboxylic acids (and reactive acid derivatives such as esters and acid halides) as reaction raw materials for polyesterification or polyurethane formation with the cyclic boron compound (VI) and diisocyanate compounds include malonic acid, maleic acid, succinic acid, and adipic acid. , Sebacic acid, dodecanedicarboxylic acid,
Examples include phthalic acid, terephthalic acid, dodecyl succinic acid, polybutenyl succinic acid, ethylene diisocyanate, hexamethylene diisocyanate, tolylene diisocyanate, diphenyl-4,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate.

The tertiary amine (II) to be reacted with the organoboron polymer compound (I) has at least one tertiary amine in the molecule.
Hydroxyl groups. R ₃ and R in the general formula (II)
_4, R ₅ are methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t
-Butyl, hexyl, dodecyl, hexadecyl, octadecyl, docosyl, cyclohexyl,
Hydrocarbon groups such as phenyl group, tolyl group, benzyl group and phenethyl group, methylol group, 1-hydroxyethyl group,
2-hydroxyethyl group, 2-hydroxypropyl group,
A 2-hydroxyisopropyl group, a 3-hydroxypropyl group, a 2-hydroxybutyl group, a 6-hydroxyhexyl group, an α-hydroxyphenethyl group, a polyethyleneoxy group having 2 to 40 repeating units having a hydroxyl group at the terminal, and a hydroxyl group at the terminal. And a polyisopropyleneoxy group having 2 to 26 repeating units. Specific tertiary amines (II) include diethylmethanolamine, diethylethanolamine, methylethylethanolamine, dimethyl-2-propanolamine, dibenzyl-
Ethylene oxide of 2-propanolamine, diethyl-α-hydroxyphenethylamine, methyldiethanolamine, cyclohexyldiethanolamine, methyldi-2-propanolamine, hydroxymethyldiethanolamine, triethanolamine, tri2-propanolamine, dihexadecylamine (2-35 Mol) adduct, propylene oxide of butylamine (2
~ 13 mol) bis adduct, N, N-diethyl-N ',
N'-di-2-hydroxyethylethylenediamine,
N, N, N ', N'-tetra-2-hydroxyethylethylenediamine and the like. These tertiary amines
(II) has a total carbon number in the range of 5-82.

Specific examples of the charge transfer type conjugate according to the present invention include charge transfer type complexes represented by the following chemical formulas (1) to (11). These compounds have a hydroxyl group and a hydrogen atom bonded to the C-terminal and the O-terminal, respectively.

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[0028]

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[0029]

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[0030]

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Highly polar polymer materials such as charge transfer conjugates and epichlorohydrin rubbers are very expensive at present. Therefore, the charging member 1 having a two-layer structure in which the thickness of the conductive elastic layer 1b is relatively large has a surface which cannot be called a preferred embodiment, but is substantially equivalent to a charging member having a three-layer or four-layer structure. This is the same as the case where the resistance layer 2d in No. 2 is very thick. In other words, a remarkably excellent effect is obtained in that the dielectric strength is increased without causing charging failure. Further, the conductive bases 1 of the charging members 1 and 2
A superimposed DC and AC voltage is applied between a and 2a and the conductive substrate of the member to be charged (for example, the photoconductor 11 shown in FIG. 5). The DC voltage is preferably in the range of 200 to 1500 V, and the peak-to-peak AC voltage (V _PP ) is preferably in the range of 1 to 4 kV.

The method for manufacturing the charging member of the present invention will be briefly described. In the case of a two-layer structure, a rubber material, a charge transfer type binder, a vulcanizing agent and a softener, a vulcanization accelerator, an accelerating aid, a conductive agent, a non-conductive filler, a dispersing agent And a compounding agent such as an antioxidant are sufficiently kneaded with an open roll or a kneader to prepare a conductive rubber compound. Next, the rubber compound is molded by a compression molding method, an extrusion molding method, or the like, and vulcanized to form a conductive elastic body layer (1b) having a predetermined thickness directly on the conductive substrate (1a). Thereafter, a polymer material, a conductive agent, and additives appropriately added are added to an organic solvent and mixed well to prepare a coating solution for forming a surface layer. Next, the coating liquid is applied onto the conductive elastic layer (1b) by an appropriate coating method such as an immersion method or an air spray method, and then dried at room temperature or by heating to dry the surface layer (1c).
Is formed, the charging member (1) of the present invention is manufactured.

In the case of a four-layer structure, a rubber compound is prepared by mixing and kneading a rubber material, a conductive agent, a vulcanizing agent and, if necessary, the above-mentioned compounding agents. The conductive rubber layer (2b) can be formed by any of the usual rubber molding methods such as compression molding, transfer molding, extrusion molding, injection molding, and reaction casting. When the rubber layer (2b) is made of a foam, a foaming agent is previously mixed into the rubber compound or an inert gas is mixed by a gas mixing method, and the rubber layer (2b) is formed by a compression molding method or the like. be able to. Examples of the blowing agent include azo-based compounds such as azodicarbonamide, α, α'-azobisisobutyronitrile and diazoaminobenzene, sulfohydrazide-based compounds such as benzenesulfonylhydrazide and p-toluenesulfonylhydrazide, and dinitrosopentamethylenetetramine. And the like. Nitrogen gas, carbon dioxide gas, or the like is used as the inert gas. Then, a bleed prevention layer is formed by the same coating method as that for the above-mentioned surface layer (1c).
(2c) can be coated on the rubber layer (2b).

Next, the polymer material and the charge transfer type conjugate are added to an organic solvent and mixed well to prepare a coating solution for forming a resistance layer. The charge transfer conjugate is methanol,
Alcohols such as ethanol and butanol; ketones such as methyl ethyl ketone and methyl isobutyl ketone; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as methylene dichloride and chlorobenzene; esters such as ethyl acetate; Good solubility in ethers such as ether and dioxane, and general-purpose solvents such as dimethylformamide. Therefore, a solvent that dissolves the high-polarity polymer material is selected, and if necessary, the polymer material is masticated, and then the charge transfer type binder is dissolved in the solvent to prepare the coating solution. . Next, this coating liquid is applied on the bleed prevention layer (2c) by the above-mentioned coating method, dried and, if necessary, thermally cured to obtain a resistive layer.
(2d) is formed. Further, when the surface layer (2e) is coated on the resistance layer (2d) in the same manner as in the case of the two-layer structure, the charging member (2) of the present invention is manufactured.

While the roll-shaped charging member (charging roll) has been described above, the charging member of the present invention may be in the form of a block, blade, or belt. The block-shaped or blade-shaped charging member has a two-layer structure, as shown in FIGS. 3A and 3B, with respect to the thickness direction, on the side opposite to the charged member on which the charging members 3 and 4 are pressed and arranged. The conductive elastic layers 3b, 4b are adhered and fixed to the plate-shaped conductive bases 3a, 4a, and the elastic layers 3b, 4b
The surface layers 3c and 4c are covered thereon. Further, as shown in FIG. 3C, the belt-shaped charging member moves in the direction of the arrow.
The charging member 5 having a layered structure includes an electrode roll (conductive base) 5a.
And the electrode roll 5
a is pressed against the member to be charged. The belt-shaped charging member 5 does not necessarily have to be moved and may be of a fixed type. The layer structure of each charging member may be the above-described single layer, three layers, or four layers. The charging member of the present invention,
The present invention can be applied to a transfer device, a static eliminator, and the like in addition to the charger. When used as a charging member in a transfer device, the charging member is pressed against a member to be charged such as a photoreceptor via a transfer material such as paper, and its volume specific resistance is adjusted to a range of 10 ⁷ to 10 ¹⁰ Ωcm. You. Further, when used as a charging member in a static eliminator, the charging member directly contacts the member to be charged,
Its volume resistivity is adjusted in the range of 10 ² to 10 ⁴ Ωcm.

(Effect of the Invention) The above-described charge-transfer type conjugate comprises the conductive elastic layer (1b) or the resistance layer (2).
It has excellent properties as a constituent material of d). i) A layer in which carbon black, conductive metal powder, or the like is dispersed generally has poor resistance uniformity, whereas a layer in which a charge transfer type binder is dispersed has good resistance uniformity and reduces image defects such as uneven charging. Does not occur. ii) The environmental dependency of resistance is very small, and it shows stable charging performance from low-temperature and low-humidity environment to high-temperature and high-humidity environment. No charging failure occurs in low-temperature and low-humidity environment. . That is, the original function of the conductive elastic layer or the resistance layer can be realized. The reason for this is that, because of the intramolecular charge transfer complex structure, it is not due to ionic conduction such as ECO or a rubber layer in which perchlorate is coordinated, but to electronic conduction, which has a small environmental dependence of resistance. It is presumed.

[0037]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to the following Examples. (Image Forming Apparatus) FIG. 4 is an overall explanatory view of an image forming apparatus incorporating the roll-shaped charging member of the present invention shown in FIG. In FIG. 4, a cylindrical photoconductor (drum) 11 that rotates in the direction of the arrow is disposed inside the main body of the image forming apparatus U, and functions as an electrostatic latent image carrier. A laser writing device 12 that writes an electrostatic latent image on the surface of the photoconductor 11 is arranged on one side inside the image forming apparatus U main body. Around the photoreceptor 11, a charger 13 for uniformly charging the surface of the photoreceptor 11 in order along its rotation direction, a developing unit 14 for visualizing the electrostatic latent image, and a paper ( Transfer device 15 for transferring the image onto transfer material) and photoconductor 11
A cleaning device 16 for removing the upper residual toner is provided. The developing device 14 has a container 14a for storing toner. In this container 14a,
Agitating members 14b, 14b for agitating the toner, a rotatable developer carrier 14c, and a toner supply roller 14d for supplying toner to the carrier 14c are provided. The developer carrier 14c faces the opening of the container 14a,
The photoconductor 11 is supported by the container 14a with a slight gap. The cleaning device 16 has a casing 16a. A metal blade holder 16b is fixed to the casing 16a, and a sheet-like cleaning blade 16c is fixed to a tip of the blade holder 16b. The edge of the tip of the cleaning blade 16c is in contact with the surface of the photoconductor 11.

At the lower part of the main body of the image forming apparatus U, a paper feed tray 17 for storing paper is arranged. Paper tray 1
A paper take-out roller 18 for taking out paper one by one from a paper feed tray 17 is arranged at an upper end portion of the upper surface 7. A pair of paper transport rollers 19 is provided above the side of the paper take-out roller 18.
A pair of paper guides 20 for guiding the paper conveyed by the printer are arranged. A heating roller 21a and a pressure roller 21b are provided on the upper side of the other side inside the image forming apparatus U body.
Is provided, and the fixing device 21
A transfer path 22 for transferring the sheet on which the toner image has been transferred is provided between the transfer device 15 and the transfer device 15. Above the fixing device 21, a pair of discharge rollers 23 and a transport path 24 for guiding the sheet on which the toner image is fixed from the fixing device 21 to the discharge rollers 23 are provided. A discharge tray 25 on which sheets discharged from the discharge roller 23 are placed is formed on the upper surface of the image forming apparatus U main body.

(Charger) FIG. 5 is an enlarged view of a main part of FIG. 4 and shows the structure of the charger. In FIG. 5, the charger 13
Is provided with the roll-shaped charging member 1. Charging member 1
The cleaning device 1 has both ends of the conductive substrate 1a.
6 is supported by a support member 31 fixed to the casing 16a. The charging member 1 is moved by the urging force of two pressure springs 32, one end of which is fixed to the support member 31 and the other end of which is fixed to the end of the base 1a.
It is pressed and in contact with the surface. A metal pad holder 33 is fixed to the support member 31, and a sheet-like cleaning pad 34 fixed to the end of the metal pad holder 33 removes the toner even if it adheres to the surface of the charging member 1 very slightly. It is designed to be removed. Further, a superimposed oscillation voltage is applied to the base 1 a of the charging member 1 from a DC power supply 35 and an AC power supply 36 connected in series. Therefore,
The charging member 1 can uniformly charge the surface of the photoconductor 11 rotating in a predetermined direction while contacting the surface layer 1c by the conductive elastic layer 1b and the surface layer 1c via the base 1a.

The operation of the image forming apparatus U in the present invention is as follows.
This is the same as the conventional one, and is briefly described as follows. As described above, the surface of the photoconductor 11 rotating in the direction of the arrow is uniformly charged by the charging member 1 to which the superimposed oscillation voltage is applied. Photoreceptor 11 uniformly charged
Is written with an electrostatic latent image by the laser writing device 12.
The electrostatic latent image on the photoconductor 11 is developed into a toner image by the developing device 14. The toner image is transferred to the paper feed tray 1 by the transfer device 15.
7 is transferred to a sheet conveyed from the printer 7. After the transferred toner image is fixed by the fixing device 21, the sheet is discharged onto a discharge tray 25 by a discharge roller 23. After the toner image is transferred onto the sheet, the toner remaining on the surface of the photoconductor 11 is removed by the blade 16c of the cleaning device, and is prepared for the next electrophotographic process.

In the following examples, "parts" indicating the ratio of the polymer material such as a rubber material and the compounding agent used means "parts by weight". Example 1 The following rubber compound was kneaded by a conventional method, and the obtained rubber kneaded material was previously primed and had an outer diameter of 6 mm and a length of 2 mm.
A 2 mm thick coil was wound around a 97 mm stainless steel core. This unvulcanized rubber roll was heated to 170 ° C. and maintained at the same temperature for 10 minutes for vulcanization. By the above compression molding method,
A charging member having a single-layer structure was manufactured. ECO (CG-102: manufactured by Daiso Corporation) 100 parts Charge transfer type complex represented by the chemical formula (7) 10 parts 2,4,6-trimercapto-s-triazine 0.9 parts (JISNett-T: Nippon Zeon) N- (cyclohexylthio) phthalimide 1 part (Santogard PVI: Monsanto) Nickel dithiocarbamate (NBC: DuPont) 1 part Stearic acid 2 parts Magnesium oxide 5 parts

Example 2 100 parts of a polyamide resin (Amilan CM-8000: manufactured by Toray Industries, Inc.) and 75 parts of carbon black were added to a mixed solvent of methanol and butanol, and the solid content was about 11% by weight.
Was prepared. The rubber layer (conductive elastic layer 1b) of Example 1 was immersed in this coating solution,
After drying, a surface layer (1c) having a thickness of 10 μm was formed. Thus, a roll-shaped charging member (1) having a two-layer structure was manufactured.

Example 3 A conductive rubber silicone compound (SE-463)
9U: 50% paste of 2,5-dimethyl-2,5-di (t-butylperoxy) hexane as a vulcanizing agent in 100 parts (manufactured by Dow Corning Toray) (RC-4: manufactured by Dow Corning Toray) ) 1.5 parts were added and kneaded well. The obtained rubber kneaded material is wound to a thickness of 2 mm on a stainless steel substrate (2a) having an outer diameter of 6 mm and a length of 297 mm, which has been previously subjected to a primer treatment.
Heated for a minute to cure. The formed conductive rubber layer (2b)
Has a volume resistivity of 1 × 10 ⁹ Ωcm and a hardness of JI
SA was 30 °. Since the silicone rubber compound contains a softener, the conductive rubber layer
A bleed prevention layer (2c) having a thickness of 10 μm was formed on (2b). The formation of the prevention layer (2c) was the same as that of Example 2, except that the amount of carbon black was changed to 100 parts.
In the same manner as in (1c), a coating solution having a solid content of 15% by weight is prepared.

Next, after epichlorohydrin homopolymer (CO) (Epichromer H: manufactured by Daiso Co., Ltd.) was kneaded with a kneader, a methyl ethyl ketone solution containing 20% by weight of the above homopolymer was prepared. This solution 100
2 parts of the charge transfer complex represented by the chemical formula (7) was added to the mixture, and the mixture was sufficiently stirred to prepare a coating solution for forming a resistance layer.
The obtained coating solution was applied onto the bleed prevention layer (2c) by dip coating, and then heated and dried at 150 ° C. for 30 minutes to form a film having a film thickness of 1
A 50 μm resistance layer (2d) was formed. In addition, the resistance layer
On (2d), a surface layer (2e) similar to the surface layer (1c) in Example 2 was formed. As described above, 4
A roll-shaped charging member (2) having a layer structure was manufactured. The above “CO”, 100 parts of the “CO” and the charge transfer complex
(7) Add 10 parts of the kneaded material separately to an aluminum substrate
It was applied to a thickness of 00 μm, and its volume resistivity was measured with a resistance meter (Hiresta, manufactured by Mitsubishi Yuka Co., Ltd.) to find that it was 3.2 × 10 ¹¹ Ωcm and 1.0 × 10 ⁹ Ωcm, respectively.

Example 4 A charging member (2) was prepared in the same manner as in Example 3 except that the charge transfer type conjugate was replaced with the charge transfer type complex represented by the chemical formula (8).
Was manufactured. Example 5 A curing agent based on hexamethylene diisocyanate (51HF, manufactured by NOF Corporation) was added to 100 parts of a polyester polyol (Hyurethane 5001: manufactured by NOF Corporation).
Polyurethane was synthesized by adding 0 parts by weight. 75 parts of carbon black is added to 100 parts of this polyurethane,
The mixture was vigorously stirred to prepare a coating solution for forming a surface layer. This coating solution was applied on the same three-layer resistance layer (2d) as in Example 3, dried at 60 ° C. for 30 minutes, and then heated and cured at 120 ° C. for 30 minutes to form a surface layer having a film thickness of 10 μm ( 2e) was formed. Thus, a four-layer roll-shaped charging member (2)
Was manufactured.

Example 6 A coating solution for forming a surface layer having the following composition was applied on the same resistance layer (2d) as in Example 3, and heated at 120 ° C. for 30 minutes.
By curing, a surface layer (2e) having a thickness of 10 μm was formed. 100 parts of fluorinated polyurethane (Lumiflon LF601: manufactured by Asahi Glass Co., Ltd.) 75 parts of carbon black 11 parts of a hexamethylene diisocyanate-based curing agent (Coronate HX: manufactured by Nippon Polyurethane)

Comparative Example 1 A two-layer roll of Example 3 in which a rubber layer (2b) and a bleed prevention layer (2c) were formed on a stainless steel base (2a) was used as a charging member. Comparative Example 2 A roll-shaped charging member having the same four-layer structure as in Example 3 was manufactured except that the charge transfer complex (7) was not contained in the resistance layer (2d).

(Image Evaluation Test) Each of the charging members manufactured as described above was page-printed (PR1000 / 4-
11: manufactured by NEC Corporation), and an image output test was performed by attaching the toner kit to a charger in the toner kit. In order to evaluate the dielectric strength, a hole of 1 mm penetrating the charge transport layer and the charge generation layer on the surface of the photoreceptor was made, and a low temperature and low humidity (1
0 ℃, 15% RH) and high temperature and high humidity (28 ℃, 85% RH)
The image quality was evaluated by performing image output under the following environment. Also, in order to evaluate the bleeding property, it was left in an environment of 45 ° C./85% RH for 2 weeks, then returned to room temperature, further left for one day and night, and then imaged to determine the presence or absence of contamination on the surface of the photoreceptor. did.
Table 1 below shows the layer configuration of each charging member, and Table 2 shows the test results. In addition, the symbol “〇” in Table 2 indicates that there was no problem with both image quality and bleeding.

[0049]

[Table 1]

[0050]

[Table 2]

As is clear from Table 2, Examples 1 to 3 in which the conductive elastic layer or the resistive layer contains a charge transfer type conjugate were used.
The charging member No. 6 did not cause image quality defects due to leakage and produced clear images in both low-temperature and low-humidity environments and high-temperature and high-humidity environments. Also, no contamination of the photoreceptor was observed in the bleed test. On the other hand, in the charging members of Comparative Examples 1 and 2 in which the charge-transfer type binder was not contained in the conductive elastic layer and the resistance layer, black streaks occurred due to the occurrence of leakage in a low-temperature and low-humidity environment, and a high-temperature and high-humidity Below, dielectric breakdown occurred. Further, in Comparative Example 2, black streaks due to poor charging were also observed in a low-temperature and low-humidity environment.

[0052]

The charging member of the present invention has the general formula (III)
Wherein the polymer charge transfer type conjugate represented by the formula (1) is contained in the conductive elastic layer, and is excellent in environmental stability of electric resistance. In particular, charging failure does not occur under low temperature and low humidity, and pinhole leak does not occur even under high temperature and high humidity.
A good image can be formed.

[Brief description of the drawings]

FIG. 1A is a perspective view of a charging member having a two-layer structure shown as one embodiment of the present invention, and FIG. 1B is a cross-sectional view thereof.

FIG. 2A is a perspective view of a four-layer charging member shown as another embodiment of the present invention, and FIG. 2B is a cross-sectional view thereof.

FIGS. 3A, 3B and 3C are explanatory views of different types of the charging member of the present invention.

FIG. 4 is an overall explanatory view of an image forming apparatus in which the charging member of the present invention is incorporated.

FIG. 5 is an enlarged view of a main part of FIG. 4 showing a structure of the charger.

[Explanation of symbols]

1-5: charging member, 1a-5a: conductive substrate, 1b, 3
b, 4b... conductive elastic layers, 1c, 2e, 3c, 4c.
Surface layer, 2b: conductive rubber layer, 2c: bleed prevention layer,
2d: resistance layer, 11: charged body (photoconductor).

Claims (4)

[Claims] 1. A polymer comprising at least a conductive substrate and a conductive layer containing a polymer charge transfer conjugate formed thereon, wherein the polymer charge transfer conjugate has the following general formula ( A charge-transfer complex represented by the following formula (III) obtained by reacting a semipolar organoboron polymer compound represented by the formula (I) with a tertiary amine represented by the following formula (II) And an atomic ratio of boron atoms to nitrogen atoms in the charge transfer complex of 1: 1. Embedded image [Wherein, A is a substituent represented by-(X) k- (Y) 1- (Z) m-, and n means the degree of polymerization. Here, X and Z are
And may be the same or different, and represent an oxygen atom-containing hydrocarbon group having a total of 100 or less carbon atoms having an ether residue at a terminal, and Y represents -OC-R ₁ -CO-O- group or -OCHN-R _{A 2-} NHCO-O- group (provided that
R ₁ represents a hydrocarbon group having ₁ to 82 carbon atoms, R ₂ represents a hydrocarbon group having ₂ to 13 carbon atoms), and k, l, and m each represent an integer of 0 or 1. ] (Wherein, R ₃ , R ₄ and R ₅ may be the same or different and each represents a hydrocarbon group which may contain one or more hydroxyl groups or ether residues;
The total carbon number of R ₃ , R ₄ and R ₅ is 82 or less, and at least one of them has one or more hydroxyl groups. ) (In the formula, A, n, R ₃ , R ₄ and R ₅ are as defined above.) 2. The charging member according to claim 1, wherein said conductive layer is a conductive elastic layer having a thickness of 1 to 5 mm. 3. The conductive layer at least comprises a conductive rubber layer and a resistive layer having a thickness of 20 μm to 1 mm and formed on the conductive rubber layer and containing the polymer charge transfer type conjugate. The charging member as described in the above. 4. The charging member according to claim 2, wherein a surface layer made of polyamide or polyurethane is formed on the conductive layer.