JPS61126567A - Formation of image - Google Patents

Abstract

PURPOSE:To form a high-quality image stably in many times by regulating the max. potential of a charge for forming an electrostatic latent image to ¦400-700¦ V, and the min. value of the gap between a latent image bearing body and a developer carrying body within 0.30-0.65mm, and forming a carrier prepared by coating its core material with a specified compsn. to form a coat. CONSTITUTION:The following requirements have to be satisfied in the image forming process: The absolute voltage of the max. potential of an org. photosensitive body (OPC photoconductor) for forming the latent image is within 400-700V, when it is charged, and the min. value (Dsd) of the gap between the latent image bearing body and the developer carrying body in a developing zone is within 0.30-0.65mm, and the carrier is prepared by coating the core material with the coating layer of or a compsn. contg. a polymer contg. a fluorinated vinyl polymer made from a monomer as an essential structural units, preferably, >=50wt%, represented by the formula in which each of X<1>-X<4> is H, Cl, F, lower perfluoroalkyl, or lower perfluoroalkoxy, each independent of each other, and at least 2 of them are F.

Description

[Detailed description of the invention]

[Field of application in the field of trade] The non-invention is electrophotography using an M-type conductive photoreceptor, -
#Stains formed by electrographic method, electrostatic printing method, etc. 1! ll1i, which includes the step of: t) developing the image using a two-component developer;
Related to image forming method [Prior art] At present, in order to form a visible image from the information power, 73 methods such as electrophotography using a latent image are widely used. There is. For example, according to an example of electrophotography,
The electrostatic latent image formed on the layered image bearing member made of the electrically conductive photoreceptor through the charging step and the 311 step is developed with a developer called a toner made of electroscopic layer color particles, and this toner image is developed. is usually transferred to a transfer material and fixed to obtain a visible image. The developer used to develop such a silent image is a so-called two-component developer consisting of a mixture of toner and carrier, and a magnetic toner rich in magnetic material. The so-called one-component 3Am used alone in
However, in one system using a two-component developer,
Since the toner is triboelectrically charged by mechanically agitating the toner and carrier, it is possible to fairly schematically control the toner's charging polarity and phosphorescence by selecting the characteristics of the carrier, stirring conditions, etc. In this respect, it is better than single-bottom developer. Development methods include the magnetic brush method, cascade method, etc. Of these, the magnetic push method is preferably used. The advantage of the 5Jt image agent standing up like a brush is that it forms a magnetic brush, and this magnetic brush is fi! In a developing method that utilizes the OO magnetic brush method, which is a method of developing by rubbing toner particles on the surface of an image carrier and layering toner particles on an electrostatic latent image, the electric field in the developing area is The strength of f is one of the important conditions that determines the developing method. Among the factors that determine the electric field strength, the surface potential when the photoconductive photoreceptor that constitutes the latent image carrier is charged is % S in the development area, the distance between the latent image carrier and the developer transport carrier, and the electrical resistance of the developer (particularly the carrier in a two-component developer), and the electric field strength depends on the correlation of these factors. It is determined. On the other hand, in recent years, organic photoconductive photoreceptors have been used, which are considered to be advantageous in that they not only have high negative durability and stable photosensitive characteristics over a long period of time, but also are highly safe and inexpensive. However, since this organic photoconductive photoreceptor generally has low photosensitivity, the potential difference between the non-image area that is irradiated with light and the image area that is not irradiated with light during the exposure process is small. For this reason, image forming methods using organic photoconductive photoreceptors generally have the drawback that the density of the visible images obtained is low, and
Due to the delicate nature of L-sensitivity, slight fluctuations in developing conditions can have a large effect on the visible image, resulting in stable and excellent visible images. ! Problems such as difficulty in obtaining ji1i* are addressed. [Object of the Invention] The present invention has been made against the above-mentioned background, and its object is to provide an image forming method using an organic leading IE photoreceptor with high tj without image unevenness.
An object of the present invention is to provide an image forming method that can stably form high-quality images having f density over many times. [Structure of the Invention] The above object is to transfer organic light 4 to an M-carrier made of a photoreceptor for $1! In an image forming process including a step of forming an image and developing a recorded latent image by a developer transporting carrier facing an aS carrier carrying a developer consisting of toner and carrier in a developing area, The absolute value of the highest electric potential (a) of the charge forming the silent 11E latent image is 400 to 700, and the minimum value of the gap between the latent image carrier and the developer transport carrier constituting the development area is 0.30- The carrier was provided on the core material and the surface of the core material. By an image forming method characterized by comprising a polymer of a monomer composition mainly composed of a monomer represented by the following general formula (D) or a coating layer of a composition containing the polymer. Achieved by the general formula (D (wherein XI, X2,
They may be the same or different from each other (, XttX2, X
At least two or more of 3 and X4 are 7 no atoms. ) Hereinafter, the present invention will be explained in detail based on a series of cases in which the present invention is applied to electrophotography. In the present invention, the organic light guide is used as a photoreceptor (rop
A latent image carrier consisting of a CG light body (also referred to as a CG light body) and a developer transporting carrier are placed facing each other across an area, and the latent image carrier is transferred.

[However, the amount of Ka formed on the carrier is
At the same time, the image is moved to the developing area, and a magnetic brush made of a two-component developer consisting of toner and carrier, which is formed by magnetic force on a developer transporting carrier, is carried into the developing area. The electrostatic latent image on the latent image carrier is rubbed to remove the toner particles in the magnetic pusher.
Development is achieved by electrostatically adhering to the electrostatic layer, and the following conditions (a) to r must be satisfied in the above steps. ←) The absolute value of the highest potential of the silent image when the OPC$ light body constituting the a image carrier is closed is within the range of 400 to 700 (A is negative) To be. (c4 Minimum one straight line (Dsd) of the gap between the latent image carrier and the developer/agent transport carrier in the development area is 0.30 to 0.6
(c) The crack must be within the range of 5mm. (a) and (b) have a coating layer made of a vinyl-based polymer containing a vinyl polymer containing a monomer composition or a composition containing the polymer;
By satisfying (3) and (c), the one-world state in the development area can be made appropriate, and good development can be achieved.As a result, the image! 1 degree is high and suppresses the occurrence of image unevenness or capri-6
It is possible to form a high quality image. Electrostatic fI in the OPC photoreceptor constituting the layered image carrier!
If the absolute value of my highest potential (b) is outside the range of condition p) and the value is less than 400, it will be difficult to obtain the required electric field strength, whereas if it exceeds 700, OPC It is necessary to increase the film thickness of the photoreceptor, which lowers the angle of 8 degrees, which is undesirable from a commercial standpoint. The minimum value (D
If sd) is outside the range of 1 condition ←) and the beak is 0.3 Qmm, it becomes difficult to obtain a uniform developing effect in the developing area, and image defects are likely to occur. On the other hand, when Mahara's Dsd exceeds 0.65 mm, the effect of the opposing electrode between the toner particles and the layer image decreases in the fA image area, and the li! i* agglomeration is easy to mark, and the edge effect of having more toner layers on the contours than the center of the latent image appears greatly. When the carrier satisfies the condition (c), the carrier becomes insulating and has an electrical resistivity of 0.11Ωcm or more, which is a two-component developer containing a leakage phenomenon, that is, an I-class carrier. The electrostatic charge m'a formed on the image bearing member or the toner charge does not leak out through the magnetic brush formed by the magnetic brush, and therefore the distribution state of the electrostatic charge is It is possible to prevent the toner from changing or the toner's % charge state from becoming inappropriate, and to achieve good development. Note that the electrical resistivity value refers to the cross section &1 cm" (F cm"
) The sample was placed in a measuring cell (o, oa ~ o, oscmo hcm), and a load of one edge was applied from the top surface, and the current value (i ampere) was calculated when the applied voltage (V volts) was varied. Measure it and use the formula below to calculate it. Furthermore, in a carrier having a coating layer made of the above-mentioned fluorine-containing vinyl polymer or a composition containing the polymer, the fluorine-containing vinyl polymer has a strong tendency to be negatively chargeable and has no positive charging function for toner. Therefore, it is possible to make the developability of the OPC ill-light material, which is normally given a negative surface potential, sufficiently high, and it is possible to improve image preparation and prevent the occurrence of capri. Moreover, the above-mentioned fluorine-containing vinyl polymer has excellent water resistance and can increase the water resistance of the carrier. Next, the present invention will be explained in more detail. For example, a developing sleeve is preferably used as the developer transporting carrier for supplying the two-component developer to the developing area. There are two types of developing sleeves: one consisting of a plurality of sleeves and one consisting of one sleeve, but images can be formed more preferably with one consisting of one sleeve. The developer transport carrier may be of a structure to which a bias voltage can be applied; for example, a cylindrical sleeve with a magnetic brush supported on its surface, and a plurality of tubes arranged inside this sleeve. A magnet body with magnetic poles
By rotating the sleeve, the magnetic brush on the sleeve is carried into the developing area. In order to perform uniform development without unevenness, it is preferable that the magnetic brush carried on the developer transport carrier be carried into the development area in a uniform state. It is preferable that a regulating blade for regulating the height of the magnetic brush is provided on the upstream side of the region so that the height of the magnetic brush can be trimmed to a constant level. The regulating blades may be made of magnetic material or six of them may be made of non-magnetic material. The giant ship (Hcut) between the tip of the regulating blade and the surface of the developer transport carrier is. It is set in relation to the minimum size of 1 m (Dsd) of the gap between the layered image carrier and the developer transport carrier in the development area, but the tip of the magnetic brush should be in moderate contact with the wt development surface of the submerged image carrier. Moreover, in order to be able to supply a sufficient amount of toner to the development area so that the image density is high, the distance ()icut is the minimum of the gap 1[it CD5d
) is preferably about 0.8 times as concealed. A bias voltage can be applied to the development area as necessary. This bias voltage is generally only a DC voltage, but it may also be a voltage in which an AC voltage is superimposed on a DC voltage. In this case, the DC voltage prevents toner particles from adhering to the background area other than the IR area. Not only this effect is obtained, but also the toner particles are easily dispersed from the Φ Yaria particles due to the flowing pressure, and the toner adhesion to the fI image is improved. The magnitude of the DC voltage is preferably 0 to 30 in absolute value.
6 at about 0V, and the effective value of AC voltage is, for example, 100V ~
Approximately 5KV, frequency is for example 100Hz to 10KHz
That's about it. The toner image formed by the above development process is transferred to a transfer material such as paper by, for example, an electrostatic transfer method, and then the transferred image is placed in a fixing device and electrolytically processed by a contact heat fixing method using, for example, heated cola. , thereby forming a visible image. The latent carrier used in the invention is a photoreceptor (O
(PC photoreceptor). This 0PC photoreceptor +
1. A photosensitive layer comprising a photoconductive substance such as an organic compound alone or optionally dispersed in a binder resin is formed on a conductive support. Such a photosensitive layer includes a carrier generation layer containing a carrier generation substance that absorbs visible light and generates charged carriers, and a carrier that transports either or both of positive and negative carriers generated in this carrier generation layer. It is preferable to have a two-layer structure in which a carrier transport layer containing and releasing a transport substance is combined. In this way, by assigning the two basic functions necessary for the photosensitive layer, ie, generation of carriers and transport thereof, to separate layers, the range of materials that can be used in the composition of the photosensitive layer can be widened. 1. It is now possible to independently select a VJ negative or material system that optimally performs each function, and by doing so, it is possible to achieve the characteristics required in the Hiroko Shagu process, for example, the surface when charged. It becomes possible to develop a photoreceptor that has a high potential, a large charge retention capacity, a high photosensitivity, and has excellent physical properties such as stability in repeated use. Examples of carrier-generating vB substances include anthonthrone pigments, perylene conductors, butalocyanine pigments, azo dyes and indigoid dyes, and examples of carrier-transferring substances include carbazole derivatives, Examples include oxadiazole derivatives, triarylamine derivatives, polyarylalkane derivatives, hydrazone derivatives, pyrazoline derivatives, stilbene conductors, and styryltriarylamine derivatives. Examples of binder resins constituting the photosensitive layer in the OPC photoreceptor include polyethylene, polypropylene, acrylic resin, methacrylic resin/vinyl chloride resin, vinyl acetate resin, epoxy resin, polyurethane A4A, phenol resin, polyester resin, pulqueid resin, and polymer resin. 'Addition polymerization resins such as recarbonate resins, silicone resins, and melamine resins. Summer addition type resin 1 Superposition 1' resin, as well as co-polymer resin 1 containing two or more of the repeating units of these resins 1 For example, vinyl chloride-vinegar is a vinyl copolymer 6! 1 fat, vinyl chloride - Vinyl acetate-maleic anhydride copolymer resin, styrene-acrylic copolymer resin
)-N-vinylcarbazole and the like can also be mentioned. Examples of materials constituting the support for the OPC sensitizer include aluminum,
Niggle, W4. A sheet of gold such as zinc, copper, silver, tin, gold, stainless steel, gold, etc. can be used. Such an OPCg element may have a particular airframe configuration, but the S is not limited to a shoe, and any configuration may be used. 1 to 5F & 6 each show an example of the mechanical structure of an OPC photoreceptor, and FIG. 1S and FIG. This is an example in which a photosensitive layer 14 is provided at the bottom of the laminate of the layer 12 and the carrier transporting layer 13 containing a carrier transporting layer 13 as a main component. Figures 2 and 14 are examples in which an intermediate layer 15 is provided between the photosensitive layer 14 and the 4ta support 11, respectively. 5 and 5gb respectively show a layer 14 formed directly on the conductive support 11 in which a carrier-generated material [17 is dispersed in a layer 16 mainly composed of a carrier-importing substance]. This is an example in which the toner is provided through the intermediate layer 15.The toner constituting the two-component '3!A image agent used in the invention is made by dispersing toner components such as skin color M in a binder resin. As the binder resin, a variety of thermoplastic resins are used. Specific examples thereof include styrenes such as styrene, parachlorostyrene, and α-methylstyrene; acrylic methyl, and acrylic ethyl. , acrylic defeat n-7”
α-methylene MI such as lobil, acrylic H9 waryl, acrylic & 2-ethylhexyl, methyl methacrylate, methyl methacrylate, n-butyl methacrylate, lauryl methacrylate, memecryl #R2-ethylhexyl
Fvj & monocarboxylic esters; vinyl nitriles such as acrylonitrile and methacrylonitrile; 2-
Vinyl pyridines such as vinyl pyridine and 4-vinyl pyridine; Vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether; Vinyl ketones such as vinyl methyl gutton, methyl ethyl gutton, and methyl isopropenyl ketone; ethylene, prohylene-isogrene,
Polymers of monomers such as unsaturated hydrocarbons such as butadiene and their halides, halogenated unsaturated hydrocarbons such as chloroprene, or two or more of these monomers; 1) - Sowing Copolymers, S, and mixtures thereof obtained by Examples of colorants include carbon black, nigrosine dye, aniline blue, calco oil blue, chrome yellow tart 2 marine blue, methylene flu, and rose bengal. , Phthalocyanine Blue, X
fCki It is possible to mention mixtures of these. Toner components other than the color retention agent include a charge control agent, an off-load prevention agent, an adhesion improver, etc., and if necessary, fine magnetic powder may be added. The toner can be obtained by the toner back-track method of Jubei Kaichi, and a toner having an average particle size of 20 pm or less, particularly preferably 8 to 12 μm, is preferred. The carrier constituting the two-component developer used in the present invention is a core material, The above general formula (
11. The monomer represented by I) is preferred. < is 50% or more, and has a coating layer made of a polymer of a monomer composition containing 50% or more (hereinafter also referred to as "specific polymer") or a composition containing a specific polymer. It is a particulate powder. Examples of the monomer represented by the general formula 〇) include those represented by the following structural formula. (1) CF2=CFz rTFEJ (tetrafluoroethylene) (2) CF2=CF
(Hexafluoropropylene) CF3 (3) CF2-CFC4rcTFEJ (10 l)
lJ fluoroethylene) (4) CHz-CF2 r
VdFJ (fluoride and nitrogen) (57CFz-CF
(Perfluoroglobin vinyl ether) QCs F y The polymer of the foot is obtained by polymerizing a monomer assembly containing preferably 5 otts or more of a monomer represented by the general formula (D), Examples of other monomers that can be used include ethylene, propylene, etc. Substances that can be included in the composition containing the specific polymer include styrene, rubber, etc. Styrenes such as 5-crosstyrene and α-methylstyrene; methyl acrylate, ethyl acrylate, acrylic@n-propyl, acrylic lIl!lacryl, acrylic relatives 2-ethylhexyl, ethyl methacrylate, ethyl methacrylate,
Methacrylic W1n -butyl, Methacrylic &#! α-methylene BTI such as lauryl and methacrylic relatives 2-ethylhexyl Fat! Examples include monoproduced polymers such as heptanocarboxylic esters, copolymers obtained by combining two or more of these monomers, and mixtures thereof. #As the foot polymer, for example, the following can be used. Vinylidene fluoride-tetrafluor-a-ethylene copolymer → CH2CF2 Qi → CF2CF! ÷− (product name)
"VT-1oOJ (Daikin Corporation)" VT-50J (Daikin Exhibition) "Kynar 7201J (manufactured by Penpart) Polytetrafluoroethylene (PTFE) + CFzCFz+n (-product name) ("AlgofronJ (Monteca)
tfnt Edison, Inc. #1) rFluonJ (
IC1) rHalon TFEJ (Al ied
Chemical all)rHostafton
” (manufactured by Hoechst) “Polyflon J (Dyne Co.) rsorsflon J (Ugine Kuh1mJ)
i! L! Frafion TFEJ (manufactured by DuPont) Teflon JJ (manufactured by DuPont)
Polychlorotrifluoroethylene (PCT)
FE) SOCH2CFCA+Yu (product name) rDaiflon” (Daikin Exhibition) rK6
1-FJ (3M's) r Plaskon CTFEJ (At 1ied C
chemical
ne Kuh1mann) Polyvinylidene fluoride (P
VdF) + CH2CH2+n (m product name) "Duli to J (5"
1) rDyflorJ (manufactured by Dynamit Nobe1) 1” Fraf 1onJ (Ugin@Kuh1m
Ann Shao) rKE Polymer X (manufactured by Kureha Chemical Co., Ltd.)
(manufactured by Solvay) r 5olef J (manufactured by Solvay) Tetrafluoroethylene-hexafluoropropylene 1
Combination (FEP) + CH2CF2÷-1 → cF2C)'
:+CF3 (Product name) r Neof 1onJ (Tie dt'
7 companies M) “Teflon FEPj (Duhoy Company G)
) Tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) SoCFzCFz÷-÷CF2CF+ ■ C5Ft (Product name) r Teflon PFAJ (manufactured by DuPont) Tetrafluoroethylene-ethylene copolymer (ET
FE) SOCH2CH2÷-→CFzCFz+ (Product name) "Afron COP j (Asahi Glass company) rT
@fzslJ (manufactured by DuPont) Chlorotriple ethylene-ethylene copolymer n (ECT
FE) (-CH2CF2≠--9CFzCFCA (Product name) l”HalarJ (Allied Chemi
ca1 company) Ni-hexafluoropropylene copolymer + CHzCFz÷-1÷CFzcF+ CF3 (Product name) "Daiel" (Daikin Rin) rVitonJ
(Manufactured by DuPont) rFluorelJ (3M) 1” Technof Ion No FORJ (Mo
Vinylidene fluoride-chlorotrifluoroethylene copolymer + CHzCFz) - + cFz
CFC1j- (Product name) “Kel F Elagt
marJ (manufactured by 3M) Vinylidene fluoride-pentafluorozlopyrene copolymer (trade name) "Technoflo"
n T SJ (manufactured by Montedison) Nato-2 fluoroethylene-perfluoronitrosomethane copolymer (
Product name) [N1troso RubberJ (Thi
Okol Chemica 1) tetrafluoroethylene-perfluoromethyl vinyl ether copolymer (trade name) r KalregJ (manufactured by DuPont → tetrafluoroethylene-propylene copolymer CF 2
CF z+-+C)12 CH+H3 (Product name) "Ara2su" (manufactured by Asahi Glass Co., Ltd.) The core material constituting the carrier must be made of a material that can form a magnetic brush, that is, a magnetic material. Such magnetic materials include ferrite, magnetite, iron, cobalt, nickel, and other ferromagnetic metals or alloys, or compounds containing these elements, or materials that do not contain ferromagnetic elements but have been subjected to appropriate heat treatment. Alloys that exhibit ferromagnetic properties, such as manganese
Examples include aluminum, alloys of manganese and steel such as manganese-steel-tin alloys, and chromium dioxide. The 1sL diameter of this core material is, for example, 30 to 200pm, preferably 1
Preferably, the carrier has a particle diameter of 40 to 120 pm, and the shape is preferably spherical from the viewpoint of improving the fluidity of the carrier. can. That is, the specific polymer is prepared by dissolving a composition containing the polymer in, for example, a solvent to prepare a coating solution, spreading this coating solution on the surface of the core material and drying it. Form a coating layer on the surface. This shielding cloth can be prepared by a dipping method, a spray method, etc., but it is preferable to use a fluidized bed method. In this fluidized bed method, a pressurized gas flow rising in the fL fluidized bed device causes the core material to rise and float to an equilibrium height, and the coating liquid is suspended until the core material falls again. This is a method in which the coating material is sprayed from above and applied to each core material, and this process is repeated to form a coating film of a desired thickness. By this method, uniform kinship can be formed on each core material. The thickness of the coating layer is 0.2 to 5 μm, especially 0.5 to 2 μm.
Preferably it is μm. The particle size of the carrier is approximately 3
0 to Zooμm, preferably 4ON120μm, particularly preferably 50 to 75μm. When the particle size of this carrier is less than 30 μm, the fluidity of the carrier is low and the ability to convey toner to the development area is small, resulting in images #&
It is difficult to obtain carriers with such small diameters that have a uniform coating layer because the coating properties tend to deteriorate and the coating process becomes difficult during the production of carriers. - If the particle size of the carrier exceeds 200 .mu.m, the surface area of the entire carrier particles per standard weight is small, so the ability to convey the toner to the developing area is small, and the per-layer density tends to decrease. Additionally, the carrier used in the present invention may contain additives such as a charge control agent and a fluidity improver, if necessary. Next, the present invention will be described based on an example of a specific apparatus that can be used to carry out the developing process.
A: Explain the evil situation ◎Figure 7 shows an example of the device.
In FIG. 7, reference numeral 1 denotes a rotating drum-shaped image carrier made of an OPC photoreceptor, and a photosensitive layer 1b made of an organic photoconductive material is placed on a cylindrical 41E support 1a made of aluminum. This latent image carrier L is rotated in the direction of the arrow X, and is directly above the % development area Q. For example, -40
A 91d1 enclosing circle of 0 to -700V is charged to a certain value of 1, and then an exposure device (not shown) forms an electrostatic latent image corresponding to the original on the surface to be developed. The FjL latent image is moved to the 5jt image area Q and development is performed here. 2 is arranged opposite to the 1'l* carrier 1 so that the minimum value (Dsd) of the gap with the latent image carrier 1 in the development area Q is within the range of 0.30 to 0.65 mm. In addition, a sleeve made of a non-magnetic material such as aluminum, 3 is a magnet body having a plurality of N and S magnetic poles along the circumference provided inside the sleeve 2, and the sleeve 2 and the magnet body 3 are used for development. Agent gM
These sleeves 2 and magnets 3 make up the feeding carrier.
In the illustrated example, the sleeve 2 is rotated so as to move in the direction of the arrow Y, that is, in the development area Q, in the same direction as the moving direction of the magnetic carrier L, and the magnet body 3 is rotated by one foot. @ N, SJa & of the magnet body 3 are normally magnetized with a magnetic flux of 500-1500 gax X D , and due to the magnetic force, a layer of developer material consisting of a brush-like structure is formed on the thorny surface of the sleeve 20. That is, the opening 4 forming the magnetic brush is made of magnetic or non-magnetic material that regulates the amount of magnetic brush stones *II
Blade III, 5, is a cleaning blade that removes the magnetic brush that has passed through the development area Q from above the sleeve 2. The surface of the sleeve 20 after cleaning comes into contact with the developer again in the developer reservoir D6, and a new magnetic brush is formed on the surface, thereby supplying the developer. 7 is a stirring screw that stirs the developer in the developer reservoir v6 to make the components uniform. In the developer reservoir 6, the carrier is used repeatedly;
Toner is I! 4. Since the toner particles T are consumed every time an image is generated, the toner particles T are continuously replenished by the toner particles T. Reference numeral 9 denotes a supply lawn having a concave portion on its surface which carries the toner particles T into the developer reservoir 6. 10 applies a bias voltage to the sleeve 2 via the protective resistor R/bias t
It is #. In developing a static image, it is preferable that the tip of the magnetic brush lightly contact the surface of the fIIgIA carrier 1 in order to achieve uniform development. The distance (Hcut) is i
A It is preferable that the gap be about 0.8 times the minimum value (Dsd) of the gap between the layer carrier 1 and the sleeve 2 in the image area Q. Since the magnitude of the magnetic field on the surface changes, the carrier particles on the surface of the sleeve 2 follow the rotational movement of the sleeve 20 and are transported to the development area Q while rotating and vibrating. [Effects of the Invention] As described above in detail, according to the present invention, a layered image bearing member made of an OPC photoreceptor is used, and a two-part developer formed on a developer transporting carrier is used. In an image forming method including a 153A image step in which development is performed by rubbing a magnetic brush, the minimum <i (Dgd) of the gap between the carrier of the two-component developer described separately and the carrier and the developer transport carrier is specified. By doing so, it is possible to make the electric field state in the development area appropriate based on these correlations.
OPC is generally difficult to obtain a high-quality image because the original image is small.
It is important to achieve good development in the development process using a photoreceptor. As a result, while obtaining the benefits of using an OPC photoreceptor, such as high high-temperature durability and stable photosensitive characteristics over a long period of time, it is possible to obtain sufficiently high image density and clear images without unevenness. Images can be stably obtained. [Examples of the Invention] Specific *Examples of the present invention will be described below. The present invention is not limited to these Examples. (Carrier) Carrier A: Fluoride and nylidene-tetrafluoroethylene 1L@integrated “V
T-100J (manufactured by Daikin Industries, Ltd.) 15g was dissolved in a mixed solvent of acetone-methyl ether ketone (weight ratio 1:1) for 500 seconds (K#) to prepare a coating liquid, and this aa
Item for liquid, H type N powder rDSP-135CJ (fM
A core material IKP (manufactured by Aiyouko Kogyo Co., Ltd.) was subjected to 4a treatment using a fluidized bed apparatus to obtain a carrier having a coating layer thickness of approximately 2 μm. This is the "carrier person" O carrier B: Vinylidene fluoride-tetrafluoroethylene copolymer "VT-
A temporary carrier was prepared using 9 g of 1001 (manufactured by Daikin Industries, Ltd.) and 6 g of methyl methacrylate copolymer "Acrivera" MF J (manufactured by Sanmugi Rayon Co., Ltd.). .This is called “Career B”
shall be. Takayaria C: The carrier was coated with a suspension of "Polytetrafluoroethylene R 852-201J/Rya Teflon Enamel" (DuPont #) in the same manner as Carrier A, further heat treated in a furnace at about 350°C for 1 hour, and then Cooled at room temperature and classified to obtain carrier ◎This is called "Carrier C"
◎ Carrier D: A coating solution was prepared by dissolving 100,425 g of vinylidene fluoride-IIM7-ethydiethylene copolymer in a seven-tonne-methyl ethyl ketone (1:1) mixed bath [800-1]. Iron powder rDsP-2294 (same'
A core material (manufactured by MJ Iron Powder Industry Co., Ltd.) was coated using a ferry bed device, leaving a carrier with a film thickness of 2 μm. This will be referred to as "Career D." Carrier E: Vinylidene fluoride-tetrafluoroethylene copolymer “VT-
A carrier was produced in the same manner as in the production of Carrier D, except that 15 g of 100J and 410 g of methyl methacrylate copolymer "Acrivet MF" were used to prepare the carrier. This was referred to as "Carrier E." Carrier F: A carrier was manufactured in the same manner as in the manufacture of Carrier C, except that the core material was iron powder "DsP-2294." This is referred to as "Carrier F." -1. A comparative carrier was produced in the same manner as above using methyl methacrylate-styrene copolymer (copolymerization ratio 70:30) and methyl ethyl ketone as the solvent. This will be referred to as "comparison carrier A." We used a negatively charged spherical coated carrier as "comparative carrier B".
c-1018J (Nuclear Metals!!
1) was used. (Toner) Toner A: Terephthal [332g and polyoxypropylene (z,
z)-z,z-bis(4-humanmixyphenyl)propane 90g +! :, 387g of bisphenol A! . Round [7 laths] equipped with thermometer, stainless steel stirrer, glass nitrogen gas inlet tube, and falling condenser: Place in the furnace, set this flask on the mantle heater, and inject IIjL elementary gas from the nitrogen gas inlet tube. 7 :)
The temperature was raised while maintaining an inert atmosphere inside the stove. Then, 0.05 g of dibutyltin oxide was added, and while the reaction was monitored at the softening point, the reaction was carried out at 200°C.
10011 parts of this polyester resin, 10 parts by weight of carbon black "Regal 660RJ (manufactured by Cabot), and low molecular weight polypropylene "Viscol 660PJ"
(Sanyo Kasei Kogyo Co., Ltd. A toner was obtained. This will be referred to as "Toner A." Toner B: Styrene-methyl methacrylate obtained by reacting styrene, methyl methacrylate, and n-butyl methacrylate in a heptol ratio of 50:20:30. - 100 parts by weight of n-butyl methacrylate copolymer, Carmen Black "Regal 6"
60RJ (manufactured by Capot 9), 3 parts by weight of low molecular weight polypropylene "Viscol 660PJ (manufactured by Sanyo Chemical Industries, Ltd.), and 2 parts by weight of nigrosine dye "Oil Black SO" (manufactured by Orient Chemical Co., Ltd.) were mixed in a ball mill. After passing through the steps of kneading, pulverizing, and classifying, a toner having an average particle size of 11 μm was obtained. This is called "toner B". CjJ developer) The toners A and B, the carriers A-F, and the comparative carriers A and B were mixed in the combinations shown in Table M1 described below, and a two-component developer with a toner concentration of 2 weight - was mixed in a total of 14 species y
I took 4 doses. (g Photobody) A negatively chargeable two-layer*a photosensitive layer using an anthorone pigment as a carrier-generating substance and a carbazole derivative as a carrier-transporting substance is deposited on a drum-shaped aluminum cracked conductive support. Examples 1 to 9 and Comparative Examples 1 to 5 An electrophotographic copying machine using the 0P (4% photoconductor A as an image carrier) U-Bix 3000J (manufactured by Konishiroku Photo Industry Co., Ltd.)
In each of the Examples and Comparative Examples, a photographic test was carried out according to the conditions shown in Table 1 for the initial and
Check the maximum image density L (Dmax) and the occurrence of fog after 10,000 copies. The results are also shown in Table 1. In addition, stn"C is the distance between the tip of the regulating blade and the sleeve. Ni!Hcut is Dsd
X 0.8 mm, the magnet body was a fixed plate, the magnetic flux sealing on the sleeve surface was 800 Gauss, and the bias voltage applied to the sleeve was -1100 V in DC voltage. Also, the highest uij 'a 'a II (Dmax) is relative when the original image setting is 1.3! ! The occurrence of capri was evaluated using a halftone dot analyzer [Ishihara Area Duck-100J (manufactured by Konishiroku Photo Industry Co., Ltd.)]. As is clear from the results of the @Brown 1 table evaluated by the measured &, according to Examples 1 to 9 of the invention, it was possible to obtain images with sufficiently high image density without image unevenness or capri. Sata. Furthermore, even after 10,000 continuous readings, clear images without fogging could be obtained. On the other hand, in Comparative Example 1, the minimum gap value Ds
Since d is too small, image distortion 2 occurs, and in Comparative Examples 2 and 3, the minimum value of the gap Dsd is small, so image concealment is insufficient, and in Comparative Examples 4S and 5, 8 ,
In the early days of copying, it was possible to produce images with a high m-image m-type image with few capri, but after 10,000 continuous copies,
Fogging S and image production are both severely deteriorated and the quality is low.
A jn image was obtained.

[Brief explanation of the drawing]

Figures 1 to 6 show the mechanical structure of the organic photoreceptor.
Figure 7 is an explanatory cross-sectional view schematically showing an example of a developing device that can be used to carry out the developing process in accordance with the invention.・41 is a support 12...Carrier generation layer 13...Carrier transport layer 14...Photosensitive top 15・
・Intermediate layer 17...Carrier generating substance l・
...fII weight carrier 2...sleeve 3...
Magnet body 4... Regulation blade 5... Cleaning blade

Claims (1)

[Scope of Claims] 1) A latent image carrier comprising an organic photoconductive photoreceptor, on which an electrostatic latent image is formed, and a developer comprising toner and carrier is supported in the development area. In the image forming step including the step of developing the electrostatic latent image by a developer transport carrier facing the electrostatic latent image, the absolute value of the highest potential (V) of the charge forming the electrostatic latent image is 400 to 700, and The minimum value of the gap between the latent image carrier and the developer transport carrier constituting the development area is within the range of 0.30 to 0.65 mm, and the carrier is provided with a core material and a surface of the core material. Further, an image forming method comprising a polymer of a monomer composition mainly composed of a monomer represented by the following general formula (I) or a coating layer of a composition containing the polymer. Method. General formula (I) (wherein, X^1, X^2, X^3, and X^4 each represent a hydrogen atom, a chlorine atom, a fluorine atom, a lower perfluoroalkyl group or a lower perfluoroalkoxy group, They may be the same or different from each other, X^1X^2, X^3
, at least two or more of X^4 are fluorine atoms. )