JP2012063392A - Toner carrier, developing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device that can stably form toner cloud for a long period of time with low power consumption and develop an electrostatic latent image by supplying toner to an electrostatic latent image on a photoreceptor surface, a toner carrier mounted in the developing device and an image forming device provided with the developing device.SOLUTION: A toner carrier comprises: a conductive support; an insulation layer; a plurality of electrodes arranged at fixed intervals on the insulation layer; and a surface layer covering the plurality of electrodes. The toner carrier comprises: voltage-applying means for applying a voltage to the electrodes and the conductive support so that an electric field between the plurality of electrodes and the conductive support is periodically inverted. Toner cloud is formed by hopping toner by the electric field between the electrodes, the insulation layer contains at least a crosslinking reaction product of a fluororesin and a curing agent and the fluororesin is constituted by a copolymer of a fluoroethylene monomer and a vinyl ether monomer.

Description

  The present invention relates to a toner carrier, a developing device including the toner carrier, and an image forming apparatus such as a copying machine, a printer, and a facsimile including the developing device.

  In an image forming apparatus such as a copying machine or a printer, a developing device using an electrophotographic process is used. Among such developing devices, a non-contact type developing device that performs development without bringing a toner carrier carrying a developer (toner) into contact with a photosensitive member on which an electrostatic latent image is formed has attracted attention. ing. As examples of the non-contact method, a powder round method, a jumping method, a method using an electric field curtain, and the like are known.

The jumping development method (a method in which toner particles are jumped between the photosensitive member and the toner carrier) requires an applied voltage that is greater than the adhesion force between the toner particles and the toner carrier.
The electric field curtain method applies an alternating electric field to the electrode of a toner carrier having a plurality of electrodes arranged at regular intervals therein, and an electric field formed by an alternating unequal electric field generated on the surface of the toner carrier. The curtain hops precharged toner and supplies toner particles to the electrostatic latent image. Since the toner particles hop on the surface of the toner carrier, the adhesion between the toner particles and the surface of the toner carrier is reduced. Since it becomes substantially zero and the force for separating the toner particles from the surface of the toner carrier for development is unnecessary, the toner can be sufficiently conveyed to the latent image carrier side at a low voltage.
The electric field curtain type developing device disclosed in Japanese Patent Application Laid-Open No. 03-21967 of Patent Document 1 uses a developer carrying carrier in which a surface protective layer made of an insulating material or the like is coated on a plurality of electrodes. As a result, the toner charge does not leak to the electrode, and the toner charge is not lost to cause hopping failure.
Japanese Patent Application Laid-Open No. 2007-133388 of Patent Document 2 discloses that toner particles are supplied to the surface of a toner carrier without being tribocharged in advance, and the toner particles are hopped by an alternating electric field to charge the toner particles. In addition, it is disclosed that the surface of the developer carrying member is formed of a material that promotes frictional charging of the toner toward the normal charging polarity side of the toner.
However, since these developing devices are provided with two types of electrodes having different potentials on the insulating layer, leakage is likely to occur between the electrodes when a gap is formed between the electrodes. When leakage occurs between the electrodes, the electric field for hopping the toner is lost because the potential between the two types of electrodes cannot be maintained.

In order to improve resistance to leakage between these electrodes, the distance between the electrode on the insulating layer and the thickness of the insulating layer is formed by supporting one electrode on the conductive support and forming an insulating layer on the conductive support. It can take the form of isolating.
In this case, when an alternating electric field or rectangular wave is applied to the electrode to form an electric field that causes toner hopping, an electrostatic force acts between the electric charges of the conductive support and the upper electrode of the insulating layer, and a large amount of electric charge is applied to the electrode. Accumulate. For this reason, since much power is consumed, it is strongly required to further reduce the power consumption.

  The present invention has been made in view of the above problems, and has an object of low power consumption, stably forming a cloud of toner stably for a long period of time, and applying toner to an electrostatic latent image on the surface of a photoreceptor. An object of the present invention is to provide a developing device capable of developing an electrostatic latent image by supplying the toner, a toner carrier mounted in the developing device, and an image forming apparatus including the developing device.

The said subject is solved by (1)-(7) of this invention.
That is, (1) a conductive support, an insulating layer formed on the conductive support, a plurality of electrodes arranged at regular intervals on the insulating layer, and a surface layer covering the plurality of electrodes. A toner carrier having voltage applying means for applying a voltage to the electrode and the conductive support so that the electric field between the plurality of electrodes and the conductive support is periodically reversed. A toner cloud is formed by hopping the toner, and the insulating layer contains at least a crosslinking reaction product of a fluororesin and a curing agent, and the fluororesin is a copolymer of fluoroethylene and a vinyl ether monomer. A toner carrier comprising:
(2) The toner carrier according to (1), wherein the fluororesin is at least a polyol.
(3) The toner carrier according to (1) or (2), wherein the curing agent is an isocyanate curing agent.
(4) The toner carrier according to (3), wherein the isocyanate curing agent is a blocked isocyanate curing agent.
(5) The toner carrier according to any one of (1) to (4), wherein the surface layer is made of a polycarbonate resin.
(6) A developing device comprising the toner carrier according to any one of (1) to (5).
(7) An image forming apparatus comprising the toner carrier according to any one of (1) to (5).

As will be apparent from the following detailed and specific description, the present invention provides a conductive support, an insulating layer formed on the conductive support, and a plurality of electrodes arranged at regular intervals on the insulating layer. And a surface layer covering the plurality of electrodes, wherein a voltage is applied to the electrodes and the conductive support so that the electric field between the plurality of electrodes and the conductive support is periodically reversed. A voltage applying means for forming a toner cloud by hopping the toner by an electric field between the electrodes, wherein the insulating layer contains at least a cross-linking reaction product of a fluororesin and a curing agent; The resin is composed of a copolymer of fluoroethylene and vinyl ether monomer.
In the toner carrier, when an alternating electric field or a rectangular wave is applied to the electrodes to form an electric field that causes toner hopping, toner hopping can be caused with low power consumption.
As a result, a developing device capable of developing the electrostatic latent image by supplying toner to the electrostatic latent image on the surface of the photosensitive member with low power consumption, a toner carrier mounted in the developing device, and an image forming on which the developing device is mounted. A device can be provided.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 10 is a schematic diagram illustrating a toner cloud state of the developing device. FIG. 3 is a diagram illustrating a configuration of a toner carrier. It is a figure which shows the structure of another toner carrier.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention. In FIG. 1, (1) is a drum-shaped photoconductor rotating in the direction of the arrow (A), (2) is a charging roller for uniformly charging the surface of the photoconductor (1), and (3) is for image information. An exposure device that irradiates the surface of the photoreceptor (1) with laser light or the like, and (4) is a developing device that supplies toner to the electrostatic latent image formed on the surface of the photoreceptor (1). (5) is a transfer roller for transferring the toner image formed by the developing device (3) on the surface of the photoreceptor (1) onto a transfer material (P) such as transfer paper, and (6) is on the transfer material (P). The cleaning device removes toner remaining on the surface of the photoreceptor (1) from the surface of the photoreceptor (1) after transferring the toner image. (7) is a fixing device that heats and presses the unfixed toner image transferred onto the transfer material (P) and fixes it on the transfer material (P).

  A method for forming a toner image on the transfer material (P) using this image forming apparatus will be described. The surface of the photoreceptor (1) rotating in the direction of the arrow (A) is uniformly charged by applying a predetermined voltage by the charging roller (2). An electrostatic latent image is formed on the surface of the photoconductor (1) by irradiating the surface of the photoconductor (1) uniformly charged with laser light corresponding to desired image information from the exposure device (3). To do. Subsequently, toner is supplied from the developing device (4) to the electrostatic latent image formed in this way, and electrostatically attached to form the electrostatic latent image into a toner image. The toner image thus formed is biased while the surface of the photoreceptor (1) and the transfer material (P) are pressed against each other by the transfer roller (5) and the transfer material (P) is conveyed in the direction of the arrow (B). A voltage is applied to transfer from the surface of the photoreceptor (1) to the surface of the transfer material (P). Thereafter, the toner image transferred onto the transfer material (P) is heated and pressed by the heating roller (7a) and the pressure roller (7b) of the fixing device (7) to be fixed on the transfer material (P). The photoreceptor (1) having the toner image transferred onto the transfer material P in this way removes the toner remaining on the surface of the photoreceptor (1) by the cleaning device (6), and removes the surface of the photoreceptor (1). It is cleaned and again charged uniformly by the charging roller (2). Thereafter, as described above, an electrostatic latent image is formed by the exposure device (3), the electrostatic latent image is converted into a toner image by the developing device (4), and is transferred onto the transfer material (P) by the transfer roller (5). The operation of transferring the toner image and cleaning the surface of the photoreceptor (1) by the cleaning device (6) is repeated.

  The present invention is characterized by the developing device (4) for converting the electrostatic latent image formed on the surface of the photoreceptor (1) into a toner image with toner. As shown in FIG. 1, the developing device (4) in the present embodiment has a toner carrier for supplying the toner to the photoreceptor (1) from the opening (8a) in a container (8) for storing the toner (T). The body (9) is rotatably attached and is rotated in the direction of arrow (C) by a driving means (not shown). Then, the toner (T) is circulated while being stirred by the circulation paddle (10) to charge the toner (T) and supply the toner (T) to the surface of the toner carrier (9). The toner carrier (9) supplied with the toner (T) in this manner is pumped up while holding the toner (T) on the surface thereof by electrostatic force, and has a predetermined distance from the toner carrier (9). The amount of toner to be pumped is regulated by a blade-like toner regulating member (11) attached to (8). As will be described later, an alternating electric field is applied to the toner carrier (9) at the opening (8a) to form a cloud of toner (T). As a result, the toner (T) is electrostatically supplied from the cloud to the electrostatic latent image on the surface of the photoreceptor (1) to form a toner image. Reference numeral (12) in FIG. 1 denotes a toner supply port for supplying replenished toner.

The toner carrier (9) will be described.
As shown in FIG. 2, the toner carrier (9) has a laminated structure in the order of a lower layer, a conductive support, an insulating layer, an electrode pattern, an adhesive layer, and a surface layer.

FIG. 3 is a diagram illustrating the toner carrier (9).
As shown in FIGS. 3A and 3B, the toner carrier 9 is shown in FIG. 3A as a cross-sectional view taken along line AA ′ in the top view of FIG. 3B. , Having a first electrode and a second electrode, the function of one electrode being carried by the conductive support (91A), the conductive support (91A) being placed on the A phase and the insulating layer (95) The formed electrode pattern (91B) having a plurality of linear electrodes (91Bb) is set as the B phase, and toner particles are hopped by a potential difference between the conductive support (91A) and the electrode (91Bb) to form a toner cloud. To form.
The electrode pattern (91B) can be formed by processing a copper thin film formed by vapor deposition on the peripheral surface of the cylindrical support (91A) into a desired shape by a photoresist method. It is. There is no particular limitation on the formation method, and in addition to patterning using a photoresist method, it may be formed by drawing using, for example, an ink jet apparatus. As the conductive support (91A), a support made of a material having excellent conductivity such as aluminum or an aluminum alloy can be used. Moreover, there is no limitation in particular about the magnitude | size of an electroconductive support body (91A), What is necessary is just to use what the practitioner of this invention selected suitably. Further, the width (d) of the electrode (91Bb) and the distance (D) between the electrodes (91Bb) are not particularly limited, and may be determined appropriately by the practitioner of the invention. Since the distance (D) can be increased, it is possible to prevent a short circuit, which is preferable.

The formation of the toner cloud is affected by the width (d), the interval (D), the alternating voltage, and the like of the electrode pattern (91Bb). In order to form a good cloud, the electrode width (d) and interval (D) of the electrode pattern (91Bb) may be 40 μm to 250 μm and 85 μm to 500 μm, respectively. Moreover, as an alternating voltage, frequency 100Hz-5KHz and 100V-3KV are suitable.
The material constituting the electrode (91Bb) can be used as long as it is a material having high conductivity, but this is achieved by drawing an electrode pattern as a paste when applied for formation. This is preferable.

  In the toner carrier (9) in this embodiment, a single-phase alternating voltage is used as the alternating voltage power supply, but a plurality of alternating voltage power supplies having different periods can also be used. . By applying a voltage so that the positive and negative directions are periodically switched between the two electrodes provided on the carrier, the electric field on the surface of the carrier is periodically reversed in the opposite direction. The toner particles hop between the surface of the photoreceptor (1) and the surface layer (98) of the toner carrier (9) to form a toner cloud, and the toner (T) in this cloud is the photoreceptor (1). The toner image can be formed by electrostatically attracting and adhering toward the electrostatic latent image formed on the surface of ().

(Conductive support)
As a conductive support, for example, a metal such as Al, Ni, Fe, Cu, or Au, or an alloy thereof, a metal such as Al, Ag, or Au on an insulating substrate such as polyester, polycarbonate, polyimide, or glass, or A thin film of conductive material such as In ₂ O ₃ or SnO ₂ , carbon black, graphite, metal powder such as aluminum, copper, nickel, etc., conductive glass powder, etc. are uniformly dispersed in the resin to conduct electricity to the resin. It is possible to use a cylindrical support formed from a resin substrate imparted with a property, paper subjected to a conductive treatment, or the like.

(Insulating layer)
The insulating layer sandwiched between the conductive support and the electrode on the insulating layer is described. When an alternating voltage is applied between the conductive support and the electrode, the power consumption is proportional to the dielectric constant of the insulating layer. Therefore, the dielectric constant is preferably small. In addition, the insulating layer is required to have an insulating property in which an alternating voltage applied to the electrode does not leak to the conductive support, and an electrode and a surface layer can be formed on the insulating layer.
As a result of intensive studies, the inventor contains at least a cross-linking reaction product of a fluororesin and a curing agent, and if the fluororesin is composed of a copolymer of fluoroethylene and a vinyl ether monomer, It has been found that it is possible to provide a toner carrier that satisfies the required functions and has low power consumption.
The fluororesin is preferably a polyol, and the curing agent is a polyisocyanate that can cure the fluororesin, which is a polyol, for advantages such as ease of thin film formation and high film thickness accuracy. More preferable.
PTFE and polyethylene are generally known as low dielectric constant plastics, but they are insoluble or hardly soluble in organic solvents, so it is extremely difficult to form a uniform and smooth thin film on the surface of the substrate. Have difficulty. Therefore, a wet thin film formation process capable of forming a uniform and smooth thin film at the micron level is desired. However, a material that is soluble in an organic solvent has a structure such as a functional group that becomes soluble in an organic solvent. The rate will be high.
Such contradictory functions are required. However, as a result of diligent efforts, the inventors have made a uniform and smooth micron level because the fluororesin is made of a copolymer of fluoroethylene and vinyl ether monomer, and can be an organic solvent. It has been found that an insulating layer having a small dielectric constant can be formed. Therefore, the following description will focus on such a copolymer.
A fluororesin composed of a copolymer of fluoroethylene and a vinyl ether monomer contains a copolymer component such as vinyl ether and can be melted in an organic solvent. A thin film can be easily formed on a conductive support by a commonly used coating method. It can be formed and has excellent characteristics.
In addition, it has excellent insulating properties, and also has excellent resistance to organic solvents after the formation of a thin film, and the insulating layer is not attacked and destroyed by the organic solvent or the like when forming the electrode and surface layer.
Specifically, for example, Lumiflon LF-100, Lumiflon LF-200, Lumiflon LF-200F, Lumiflon LF-302, Lumiflon LF-400, Lumiflon LF-600, Lumiflon LF-600X, Lumiflon LF-, manufactured by Asahi Glass Co., Ltd. 800, Lumiflon LF-906N, Lumiflon LF-910N, Lumiflon LF-916N, Lumiflon LF-936, Lumiflon LF-9010, etc. can be used by mixing one or more of these.

As the curing agent, it is preferable to use a polyvalent isocyanate capable of curing a fluororesin that is a polyol. The polyvalent isocyanate is preferable for curing the fluororesin without significantly affecting the dielectric constant of the formed thin film.
Specifically, for example, Duranate THA-100, Duranate TPA-100, Duranate TSS-100, Duranate TSE-100, Duranate TSR-100 manufactured by Asahi Kasei Chemicals Co., Ltd., Sumika N3300 from Sumika Bayer Co., Ltd., etc. Takeuchi D-177N, Takenate D-173N, Takenate D-140N manufactured by Mitsui Takeda Chemical Co., Ltd., Nippon Polyurethane Industry Co., Ltd. Coronate HX, etc. may be used by mixing one or more of these it can.
In particular, a polyisocyanate having a blocked isocyanate structure is preferably used as the curing agent in order to improve the storage stability of the coating solution at room temperature.
Specifically, for example, Duranate TPA-B80X, TPA-B80E, 17B-60PX, E402-B80T manufactured by Asahi Kasei Chemicals Co., Ltd., Death Module BL-3175, BL4265 manufactured by Sumika Bayer Co., Ltd., etc. One kind or a mixture of two or more kinds can be used.

In addition, a melamine curing agent is also applicable. As the melamine curing agent, butylated melamine, methylated melamine, epoxy-modified melamine, partially or completely alkyletherified melamine resin, and the like can be used which are variously modified depending on applications.
Specifically, for example, DIC Corporation Super Becamine G-821-60, L-110-60, L-127-60, L-105-60 etc. Mitsui Cytec Co., Ltd. Cymel-370, Cymel-771 and Mycoat-102 can be used alone or in combination.
The insulating layer can be formed by a common coating method using a suitable solvent.

The thickness of the insulating layer depends on the material, but is preferably 1 μm or more and 100 μm or less.
If it is less than 1 μm, it is difficult to insulate so that no charge leakage occurs between the electrode and the toner. If it is thicker than 100 μm, the electric field from the internal electrode becomes weak, and it is difficult for the toner to be released from the surface layer and generate an electrostatic force that can be hopped, and 50 μm or less is more preferable.

(Surface layer)
The surface layer is required to have a function of covering the electrode, preventing leakage to the toner and the like, and appropriately charging the toner by frictional charging with the toner.
Any material used for the surface layer may be used as long as these required functions can be satisfied.Both bisphenol-based polycarbonates can achieve both triboelectric charging ability and toner hopping and can stably form a toner cloud for a long period of time. Abrasion can also be improved.

  The molecular weight is preferably 30,000 to 60,000 from the viewpoint of ease of handling when dissolved in a solvent. If the molecular weight is too small, it is easy to work when preparing the coating solution, but the volume of the polycarbonate in the coated film of the already prepared photoconductor is significantly reduced due to rapid crystallization and molecular chain rearrangement. The desired endurance strength may be difficult to obtain.

The surface layer may contain a leveling agent as an additive in the polycarbonate resin.
As the leveling agent, known materials can be used, but a silicone oil leveling agent capable of imparting high smoothness in a small amount is particularly preferable. Examples of silicone oils include dimethyl silicone oil, methyl phenyl silicone oil, methyl hydrogen polysiloxane, cyclic dimethyl polysiloxane, alkyl-modified silicone oil, polyether-modified silicone oil, alcohol-modified silicone oil, fluorine-modified silicone oil, amino-modified Examples include silicone oil, mercapto-modified silicone oil, epoxy-modified silicone oil, carboxyl-modified silicone oil, higher fatty acid-modified silicone oil, and higher fatty acid-containing silicone oil.
In addition, an appropriate amount of additives such as a plasticizer and an antioxidant can be added to the surface layer.

  The surface layer can be formed by a commonly used coating method such as a dip coating method or a spray coating method using one or more solvents soluble in a polycarbonate resin such as tetrahydrofuran.

  In the toner carrier (9) in this embodiment, a single-phase alternating voltage is used as the alternating voltage power source, but the phase or period is different (however, the vector sum is naturally zero). It is also possible to use a multiple phase alternating voltage power supply. By applying a voltage so that the positive and negative directions are periodically switched between the two electrodes provided on the carrier, the electric field on the surface of the carrier is periodically reversed in the opposite direction. The toner particles hop between the surface of the photoreceptor (1) and the surface layer (98) of the toner carrier (9) to form a toner cloud, and the toner (T) in this cloud is the photoreceptor (1). The toner image can be formed by electrostatically attracting and adhering toward the electrostatic latent image formed on the surface of ().

The thickness of the surface layer may be any as long as it can form a toner electric field curtain on the surface of the toner carrying member and can prevent the electrode (91b) from being exposed to the surface of the toner carrying member. It is preferable that it is 50 micrometers or less.
If it is 0.5 μm or less, it is difficult to insulate so that no charge leakage occurs between the electrode and the toner.
When the thickness is 50 μm or more, the electric field from the internal electrode becomes weak, so that it is difficult for the toner to separate from the surface layer and generate an electrostatic force that can be hopped.
Further, when the thickness is 5 to 50 μm, toner hopping is more stably performed.

  As described above, the present invention, as described above, has a great effect when applied to the upper and lower electrode type toner carrier shown in FIG. 3, but is applied to the comb electrode type toner carrier shown in FIG. It is possible, although the effect is not significantly great.

The comb electrode system will be described.
The toner carrier (9) is as shown in FIGS. 4A and 4B (where FIG. 4A is a cross-sectional view taken along line AA ′ in the top view of FIG. 4B). The first electrode pattern (90A) having a plurality of linear electrodes (90Aa) and the second electrode pattern (90B) having a plurality of linear electrodes (90Bb) include an electrode (90Aa) and an electrode (90Bb). ) Are alternately formed in parallel to the axial direction of the toner carrier, and the electrodes (90Aa) and (90Bb) are disposed on the electrode patterns (90A) and (90B). A surface layer (98) for protecting 90Aa) and (98Bb) is formed.
As the support (93), a cylindrical insulating support formed from a synthetic resin such as polyimide, polycarbonate, nylon, fluororesin, polyacetal, phenol, polystyrene, or aluminum, aluminum alloy, nickel, titanium, It is possible to use a cylindrical metal conductive support obtained by cutting or polishing stainless steel or the like and coating the synthetic resin.

  As the toner used in the present invention, a known toner formed by a pulverization method or a polymerization method can be used.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.

[Coating liquid for insulation layer]
190 parts by weight of a fluororesin (Lumiflon LF-200 (manufactured by Asahi Glass)) and 35 parts by weight of an isocyanate curing agent (TPA-B80E manufactured by Asahi Kasei Chemical) were mixed with 75 parts by weight of methyl ethyl ketone to prepare an insulating layer coating solution.

[Coating fluid for surface layer]
In a mixed solution of 70 parts by weight of tetrahydrofuran and 30 parts by weight of cyclohexanone, 3 parts by weight of a bisphenol Z-type polycarbonate resin (polymerized compound having a molecular weight of 50,000 consisting of structural unit M-15: Panlite TS-2050 manufactured by Teijin Chemicals), silicone oil (KF −50 (manufactured by Shin-Etsu Chemical Co., Ltd.)) 0.002 part by weight was dissolved to prepare a surface layer coating solution.

[Toner carrier]
An insulating layer having a thickness of 20 μm was formed on the cylindrical Al conductive support having a diameter of 16 mm and a length of 230 mm by dip coating with the insulating layer coating solution. This was designated as a support (91A) on which an insulating layer had been formed. A 0.8 μm-thick copper foil film, which is a conductive metal foil film, was formed on each support (91A) on which an insulating layer had been formed by vapor deposition. Further, a resist film having a thickness of 5 μm was applied on these copper foil films. A grid pattern separated by a width d = 100 μm, a length L = 200 mm, and a distance D = 200 μm on a support (91A) having an insulating layer covered with a copper film and a resist film was exposed with a laser drawing machine. Then, after developing in an aqueous Na ₂ CO ₃ solution, etching was performed by immersing in an aqueous FeCl ₃ solution to form an electrode (91Bb) having an electrode pattern (91B) having the same shape as the electrode pattern.
Next, one end of the electrode pattern (91B) of the support (91A) on which the insulating layer is formed in which the electrode having the predetermined electrode pattern (91B) is thus formed is masked to cover the maximum film thickness. A 10 μm surface layer (98) was formed by spray coating with a surface layer forming coating solution.
The surface layer (98) was applied with the electrode exposed at the end of the support (91A) on which the insulating layer had been formed. The toner carrier (9) thus produced was assembled in the developing device (4).

[Voltage application condition to electrode]
An AC bias having an average potential of -200 V at each moment having a peak of -400 V and 0 V at a peak and a terminal attached to the opening of the developing device (4) and the conductive support was applied from an AC power source at a frequency of 5 KHz.
As the toner, BK color toner (wax-free pulverized toner) mounted on imagio Neo C320 manufactured by Ricoh Co., Ltd. was supplied to the developing device (4) for use.
These developing devices and toner are incorporated into the black station of imagio Neo C320 to output images, developing device power consumption, leakage between conductive support and electrode, toner flying on toner carrier, abnormal The presence or absence of image generation was compared.

  190 parts by weight of fluororesin (Lumiflon LF-200 (manufactured by Asahi Glass)) and 35 parts by weight of isocyanate curing agent (TPA-B80E (manufactured by Asahi Kasei Chemical)) in the coating liquid for insulating layer of Example 1 in 75 parts by weight of methyl ethyl ketone Instead of the insulating layer coating solution, 140 parts by weight of fluororesin (Lumiflon LF-906N (Asahi Glass)) and 66 parts by weight of isocyanate curing agent (TPA-B80E (Asahi Kasei Chemical)) in 93 parts by weight of methyl ethyl ketone A toner carrier was obtained in the same manner as in Example 1 except that the insulating layer coating solution was used.

  190 parts by weight of fluororesin (Lumiflon LF-200 (manufactured by Asahi Glass)) and 35 parts by weight of isocyanate curing agent (TPA-B80E (manufactured by Asahi Kasei Chemical)) in the coating liquid for insulating layer of Example 1 in 75 parts by weight of methyl ethyl ketone Instead of the insulating layer coating solution, 240 parts by weight of fluororesin (Lumiflon LF-400 (Asahi Glass)) and 32 parts by weight of isocyanate curing agent (TPA-B80E (Asahi Kasei Chemical)) are added in 30 parts by weight of methyl ethyl ketone. A toner carrier was obtained in the same manner as in Example 1 except that the insulating layer coating solution was used.

  190 parts by weight of fluororesin (Lumiflon LF-200 (manufactured by Asahi Glass)) and 35 parts by weight of isocyanate curing agent (TPA-B80E (manufactured by Asahi Kasei Chemical)) of the coating liquid for insulating layer of Example 1 in 75 parts by weight of methyl ethyl ketone In place of the insulating layer coating solution containing 100 parts by weight of fluororesin (Lumiflon LF-200F (Asahi Glass)) and 33 parts by weight of isocyanate curing agent (TPA-B80E (Asahi Kasei Chemical)) in 165 parts by weight of methyl ethyl ketone A toner carrier was obtained in the same manner as in Example 1 except that the insulating layer coating solution was used.

190 parts by weight of fluororesin (Lumiflon LF-200 (manufactured by Asahi Glass)) and 35 parts by weight of isocyanate curing agent (TPA-B80E (manufactured by Asahi Kasei Chemical)) of the coating liquid for insulating layer of Example 1 in 75 parts by weight of methyl ethyl ketone In place of the insulating layer coating solution containing 190 parts by weight of fluororesin (Lumiflon LF-200 (Asahi Glass)) and 19 parts by weight of isocyanate curing agent (TPA-100 (Asahi Kasei Chemical)) in 90 parts by weight of methyl ethyl ketone A toner carrier was obtained in the same manner as in Example 1 except that the insulating layer coating solution was used.

190 parts by weight of fluororesin (Lumiflon LF-200 (manufactured by Asahi Glass)) and 35 parts by weight of isocyanate curing agent (TPA-B80E (manufactured by Asahi Kasei Chemical)) of the coating liquid for insulating layer of Example 1 in 75 parts by weight of methyl ethyl ketone In place of the insulating layer coating solution containing 190 parts by weight of fluororesin (Lumiflon LF-200 (Asahi Glass)) and 22 parts by weight of isocyanate curing agent (D-177N (Mitsui Takeda Chemical)) in 90 parts by weight of methyl ethyl ketone A toner carrier was obtained in the same manner as in Example 1 except that the coating liquid for insulating layer contained in was used.

[Comparative Example 1]
Instead of the coating liquid for insulating layer of Example 1, 110 parts by weight of alkyd resin (Beckolite M6401-50 (manufactured by Dainippon Ink and Chemicals)), melamine resin (Super Becamine G-821-60 (Dainippon) Ink Chemical Industries, Ltd.)) A toner carrier was obtained in the same manner as in Example 1 except that 60 parts by weight of methyl ethyl ketone dissolved in 110 parts by weight of methyl ethyl ketone was used.

[Comparative Example 2]
Instead of the insulating layer coating solution of Example 1, the insulating layer was formed by the same formation method as the surface layer forming method of Example 1 using the surface layer coating solution of Example 1 above. A toner carrier was obtained in the same manner as in Example 1.

[Comparative Example 3]
Insulating layer coating for Comparative Example 3 in which 30 parts by weight of polyvinyl butyral resin (Eslex B BX-1 (Sekisui Chemical Co., Ltd.)) was dissolved in 70 parts by weight of methyl ethyl ketone instead of the coating liquid for insulating layer of Example 1 A toner carrier was obtained in the same manner as in Example 1 except that the working solution was used.

Table 1 shows the measurement results and observation results of the examples and comparative examples.
Examples 1-6 have less power consumption than Comparative Example 1.
As for Comparative Examples 2 and 3, a phenomenon was observed in which the conductive support and the electrode leaked and became conductive when a voltage was applied to the electrode. Since no potential difference was generated between the conductive support and the electrode, no electric field was generated, and toner hopping did not occur on the surface of the toner carrier. The image could not be output.

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charging roller 3 Exposure apparatus 4 Developing apparatus 5 Transfer roller 6 Cleaning apparatus 7 Fixing apparatus 7a Heating roller 7b Pressure roller 8 Container 8a Opening part 9 Toner carrier 10 Circulating paddle 11 Toner regulating member A Rotating direction B Conveying direction C Rotating direction D Interval T Toner d Width 90A Electrode pattern 90Aa Electrode 90B Electrode pattern 90Bb Electrode 91A Conductive support 91B Electrode 91Bb Electrode 93 Support 95 Insulating layer 98 Surface layer

JP-A-3-21967 JP 2007-133388 A

Claims (7)

  A toner carrier comprising: a conductive support; an insulating layer formed on the conductive support; a plurality of electrodes arranged at regular intervals on the insulating layer; and a surface layer covering the plurality of electrodes. Voltage applying means for applying a voltage to the electrode and the conductive support so that the electric field between the plurality of electrodes and the conductive support is periodically reversed, and the toner is hopped by the electric field between the electrodes. It forms a cloud of toner, and the insulating layer contains at least a cross-linking reaction product of a fluororesin and a curing agent, and the fluororesin is composed of a copolymer of fluoroethylene and a vinyl ether monomer. A toner carrier.   The toner carrier according to claim 1, wherein the fluororesin is at least a polyol. The toner carrier according to claim 1, wherein the curing agent is an isocyanate curing agent.   The toner carrier according to claim 3, wherein the isocyanate curing agent is a blocked isocyanate curing agent.   The toner carrier according to claim 1, wherein the surface layer is made of a polycarbonate resin.   A developing device comprising the toner carrier according to any one of claims 1 to 5.   An image forming apparatus comprising the toner carrier according to claim 1.

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