JP2003098825A - Development apparatus and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a development apparatus which is superior in toner- releasing properties on a thin film regulating member and abrasion resistance, reduces reverse charging and can form a stable toner thin film without stripes generated in the toner thin film due to mixing of foreign particles, etc., and also provide an imaging apparatus which uses the development apparatus and can obtain images having high quality and superior in durability. SOLUTION: The one-component system development apparatus is provided with a development roller for moving, holding the toner on a surface and carrying the toner on an image-holding element and the thin-film regulating member for abutting on the development roller through the toner held on the development roller and regulating the thickness of the toner, and visualizes a latent image on the image-holding element by using the toner carried by the development roller. The imaging apparatus is provided with the development apparatus whose thin film regulating member has a surface formed from a material, including polyimide denatured silicon resin, and at least a charging means, exposure means, development means, transfer means, cleaning means, discharge means and electrophotographic photoreceptor, and uses the development apparatus as the development means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device and an image forming apparatus, and more particularly to a one-component developing device and an image forming apparatus used in an image forming apparatus such as a copying machine, a facsimile and a printer.

[0002]

2. Description of the Related Art An electrophotographic image forming apparatus prints by the following process. That is, the surface of the photoconductor is uniformly charged by the charging device, and an electrostatic latent image based on image information by the optical system is formed on the photoconductor surface. Then, when the electrostatic latent image passes through a position facing the developing device, the latent image is visualized by the adhesion of toner, and the latent image is superposed on the recording material conveyed at a timing, and the transfer device is used. Transfer the toner image to the recording material.
The transferred toner image is fixed on the recording material by passing through the fixing device. On the other hand, the residual toner on the photoconductor after the transfer process is removed by the cleaning device,
The residual charge on the photoconductor is removed by the charge removing device.

As one of developing devices used in such an image forming apparatus, a one-component developing system using one-component toner is adopted. A typical example of this method will be described below. First, the one-component toner frictionally charged at the contact portion between the developing roller and the replenishing roller that rotates in the same direction or in the opposite direction while being pressed against the developing roller with a predetermined bite amount causes the sliding friction between the developing roller and the replenishing roller. Adheres to the developing roller. Further, the one-component toner adhering to the developing roller is further frictionally charged by the contact portion between the developing roller and the thin layer regulating member provided in contact with the surface of the developing roller, and the thickness of the toner layer is regulated. As a result, a uniform thin toner layer is formed on the developing roller. This thin toner layer is supplied to the photoreceptor side while being held by the developing roller. After that, at the portion where the developing roller and the photosensitive member face each other, the one-component toner supplied from the developing roller is developed by being attracted to the electrostatic latent image on the surface of the photosensitive member due to the potential difference between the developing roller and the photosensitive member. To be visualized.

Since the thin layer regulating member used in the developing device is required to form a stable toner thin layer, the surface member which is in constant contact with the toner has excellent releasability from the toner and abrasion resistance. There is a demand for less deterioration of physical properties, etc.
Several materials have been proposed. Urethane rubber is a material having little deterioration of physical properties and excellent wear resistance (Japanese Patent Laid-Open No. 181803/1996 and Japanese Patent Laid-Open No. 248851/1996).
JP-A No. 11-327292, etc.) has a problem in toner releasability, toner adheres to the surface to change the toner chargeability, and streaks and unevenness occur in a thin layer, resulting in uniform There was a problem that a thin layer could not be obtained. Further, as a material having excellent releasability, a fluorine-based material (JP-A-9-2652)
No. 36) and silicon materials (Japanese Patent Laid-Open No. 11-272).
It is also proposed to use Japanese Patent Laid-Open No. 068 and Japanese Patent Laid-Open No. 11-231648.

However, these materials are liable to be worn, the shape and contact area of the contact portion with the developing roller are changed, and a stable toner thin layer cannot be obtained. Further, the fluorine-based material is in the triboelectrification series. However, it has a very strong negative charging property, and particularly when used in a negative charging toner, there are problems such as low toner charging property and a large amount of reverse charging toner.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, has excellent releasability and abrasion resistance of toner in a thin layer regulating member, has less reverse charge, and is free from foreign matter. Provided is a developing device capable of forming a stable toner thin layer without streaks occurring in the toner thin layer due to mixing, and an image capable of obtaining a high-quality and highly durable image using the developing device. It is an object of the present invention to provide a forming apparatus.

[0007]

In order to solve the above-mentioned problems, the present inventor has conducted diligent studies by paying attention to a thin-layer regulating member, and as a result, at least the surface of the thin-layer regulating member has a polyimide-modified silicone resin. It was found that the above-mentioned problems can be solved by forming a material containing the above, and the present invention has been completed based on this finding.

That is, according to the present invention, firstly, via the developing roller that moves while carrying toner on the surface and conveys the toner onto the image carrier, and the toner carried on the developing roller. A one-component system developing a latent image on the image carrier using the toner conveyed by the developing roller, which is in contact with the developing roller and regulates the thickness of the toner. In the apparatus, there is provided a developing apparatus, wherein at least the surface of the thin layer regulating member is formed of a material containing a polyimide-modified silicone resin.

According to the first invention, the following (i) to (vi)
The developing device described in 1. is included. The developing device according to claim 1, wherein (i) the volume resistance of the layer formed of the material containing the polyimide-modified silicone resin is 10 ¹² Ω · cm or less. (Ii) The development according to claim 1 or 2, wherein when the toner is a negatively-charged toner, the thin-layer regulating member contains a material located on the positively-charged side of the triboelectrically charged series from the polyimide-modified silicone resin. apparatus. (iii) The thin layer regulating member contains 15 parts by weight or more of a quaternary ammonium salt-containing maleimide resin and / or a quaternary ammonium salt-containing methacrylimide resin with respect to 100 parts by weight of the resin component forming the surface layer. Items 1-3
The developing device according to any one of 1. (Iv) The thin layer regulating member comprises a plurality of layers, and has an elastic layer in a layer other than at least a surface layer formed of a material containing the polyimide-modified silicone resin. The developing device as described in 1. (V) The developing device according to any one of claims 1 to 5, wherein the thin layer regulating member operates in an interleaving manner in the rotation direction of the developing roller. (Vi) The surface friction coefficient of the thin layer regulating member is 0.2 to 0.
7. The developing device according to claim 1, wherein the developing device is 7.

According to the present invention, secondly, there is provided an image forming apparatus comprising at least a charging means, an exposing means, a developing means, a transferring means, a cleaning means, a discharging means and an electrophotographic photoreceptor, and the developing means. As an example, an image forming apparatus using the developing device according to the first invention is provided.

[0011]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a developing roller that moves while carrying toner on the surface and conveys toner onto an image carrier, and a developing roller carried on the developing roller. A thin layer regulating member that contacts the developing roller via the toner and regulates the thickness of the toner, and visualizes the latent image on the image carrier using the toner conveyed by the developing roller. In the one-component developing device, at least the surface of the thin layer regulating member is formed of a material containing a polyimide-modified silicone resin. By using a polyimide-modified silicone resin with excellent mold release and abrasion resistance on the surface of the thin layer regulating member,
Since toner adhesion does not occur and the abrasion resistance is excellent, the shape and contact area of the contact portion between the developing roller and the thin layer regulating member hardly change, and it is possible to maintain the initial uniform toner thin layer. You can do it.

In the present invention, the volume resistance of the layer containing the polyimide-modified silicone resin is preferably 10 ¹² Ω · cm or less. With this volume resistance, the reversely charged toner present in the toner thin layer can be reduced by the electric field force, and the charge amount distribution of the toner in the thin layer can be made sharper.

In the present invention, when the toner is a negatively charged toner, it is preferably a thin layer regulating member containing a material positioned on the positively charged side in the triboelectric charging series with respect to the polyimide-modified silicone resin. This is because the chargeability of the toner is increased, and a good toner charge amount and a good toner attachment amount can be obtained.

In the present invention, the thin layer regulating member contains the quaternary ammonium salt-containing maleimide resin and / or the quaternary ammonium salt group-containing methacrylimide resin in an amount of 15 parts by weight per 100 parts by weight of the resin component forming the surface layer. It is preferable to contain the above. This is because uniform conductivity and good toner chargeability can be obtained at the same time.

Further, in the present invention, it is preferable that the thin layer regulating member comprises a plurality of layers, and at least an elastic layer is provided in a layer other than the surface layer formed of a material containing a polyimide-modified silicone resin. When the developing roller is rigid, the elastic layer provides flexibility to the thin-layer regulating member, so that the toner layer comes into more intimate contact with the thin-layer regulating member, which improves the uniform stability of the thin toner layer on the developing roller. Because it does.

Further, in the present invention, it is preferable that the thin layer regulating member is intermittently operated in the rotation direction of the developing roller as needed. As a result, even if a small piece of paper, plastic, sponge, or the like, or a foreign substance that suddenly disturbs the uniformity and stability of the toner thin layer from the outside is mixed into the developing device, it is removed outside the system. Because it becomes possible.

Further, in the present invention, the surface friction coefficient of the thin layer regulating member is preferably 0.2 to 0.7.
Due to this surface friction coefficient, the intermittent drive of the thin layer regulating member can be reliably performed by the rotation with the developing roller, and it is possible to provide a low-cost developing device that does not require external drive separately. Is.

The present invention is an image forming layer apparatus comprising at least a charging, exposing means, developing means, transfer means, cleaning means, charge removing means and electrophotographic photosensitive member together with the above-mentioned developing device. An image forming apparatus using the above developing device is provided. This image forming apparatus can obtain a high-quality and highly durable image. The image forming apparatus.

The present invention will be described below based on an embodiment in which it is applied to an electrophotographic apparatus which is an image forming apparatus. Figure 1
2 is a schematic cross-sectional view of a developing device and a non-magnetic single component used in the copying machine, and FIG. 2 is a schematic view of an image forming apparatus according to the present invention. In FIG. 2, this image forming apparatus is arranged in the counterclockwise direction along the circumference of the drum-shaped photosensitive member 1 in the vicinity of the upper surface thereof, and in the counterclockwise direction, the discharging exposure unit 2, the charger 3, the eraser 4,
An image exposure unit 5, a developing device 6, a pre-transfer charger 7, a transfer charger 10, a separation charger 11, a separation claw 12, a pre-cleaning charger 13, a fur brush 14, and a cleaning brush 15 are sequentially provided. Further, a registration roller 8 for feeding the transfer paper 9 between the photoconductor 1, the transfer charger 10 and the separation charger 11 is provided. The photoconductor 1 is composed of a drum-shaped conductive support and a photoconductive layer in close contact with the upper surface thereof, and rotates counterclockwise.

In the electrophotographic method using the above-mentioned image forming apparatus, the photosensitive member 1 rotates counterclockwise and is charged negatively or positively by the charging charger 3, and the photosensitive member 1 is exposed by the image exposing unit 5 to be statically charged. An electrostatic latent image is formed on the photoconductor 1. Generally, the above charger can be used as the transfer means, but it is effective to use a combination of a transfer charger and a separation charger as shown in the figure. Further, as a light source used for the image exposure unit 5, the static elimination lamp 2, etc., a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp,
Light emitting diode (LED), semiconductor laser (LD),
A luminescent material such as electroluminescence (EL) can be used. Further, various filters such as a sharp cut filter, a bandpass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range. Such a light source or the like is provided with a process such as a transfer process using light irradiation, a charge eliminating process, a cleaning process, or a pre-exposure process in addition to the process shown in FIG. It can also be used when

In the developing device 6, toner is attached onto the photoconductor 1 to develop the electrostatic latent image, the pre-transfer charger 7 adjusts the charged state of the toner image, and the transfer charger 10 transfers the toner image onto the transfer paper 9. The toner image is transferred, the electrostatic charge state between the photoconductor 1 and the transfer paper 9 is eliminated by the separation charger 11, and the transfer paper 9 is fixed by the separation claw 12.
Separate from. After the transfer paper 9 is separated, the pre-cleaning charger 13, the fur brush 14, and the cleaning brush 15 clean the surface of the photoconductor 1. This cleaning can also be performed by removing the remaining toner only with the cleaning brush 15.

When image exposure is performed by negatively or positively charging the photoconductor, a negative or positive electrostatic latent image is formed on the photoconductor. Toner charged with this positively or negatively (electro-detection fine particles)
By developing with, a positive image can be obtained, and conversely, by developing with a negatively or positively charged toner, a negative image can be obtained. A known method can be applied to such a developing unit, and a known method is also used for the charge removing unit.

In this example, the conductive support is shown as a drum, but a sheet or an endless belt can also be used. As the pre-cleaning charger, known charging means such as a corotron, a scorotron, a solid state charger (solid state charger), and a charging roller can be used. In addition, transfer charge and separation charger,
Normally, the above charging means can be used, but as shown in FIG. 5, a charger in which the transfer charge and the separation charger are integrated is efficient and preferable. As the cleaning brush, known ones such as a fur brush and a magfur brush can be used.

The inside of the developing device 6 will be described with reference to FIG. Toner (not shown) is sent to the developing roller 2 side by an agitator, moves as shown by an arrow in FIG. 3, and moves to a toner pool formed in a pressure contact portion between the supply roller 4 and the developing roller 2. . The supply roller 4 is
By rotating in contact with the developing roller 2, toner is triboelectrically charged, and the charged toner is carried on the developing roller 2 and moves to the thin layer regulating member 3. Then, the thin layer regulating member 3 causes the developing roller 2
The toner layer is brought into contact with the toner, and the toner layer having a proper and uniform thickness is conveyed to the developing area. Next, the toner is transferred to the photosensitive drum 1 on which the latent image has been written by the exposure device 22, so that development is performed. In FIG. 3, the photoconductor drum 1 and the developing roller 2 are in a non-contact state, but it is also possible for both to come into contact and develop. In this case, the developing area is generally secured by forming the photosensitive member into a belt shape instead of a drum, using an elastic member for the developing roller 2, or using a flexible structure or material for one or both of the deviations. Target. The surface of the supply roller 4 is preferably formed of a foamed elastic body. As this foamed elastic body,
For example, foamed polyurethane having a cell diameter of 50 (μm) and an Asker C hardness of 30 ° can be used. It is also possible to add carbon black or the like to make it conductive. In that case, by forming a bias electric field with the developing roller 2, control of toner supply to the developing roller 2, chargeability, etc. can be performed. You can

Next, the thin layer regulating member of the present invention will be described. The polyimide-modified silicone resin used on at least the surface of the present invention can be represented by the following general formula (1).

[0026]

[Chemical 1] (In the formula, X represents a tetravalent aromatic ring or an aliphatic ring group, R represents a divalent organic group, and n represents an integer of 5 or more.)

Generally, polyimide is known as a high-strength and rigid resin, but the introduction of a siloxane structure in the main chain gives flexibility and further has an advantage of improving releasability. . Therefore, it becomes possible to improve the abrasion resistance and the toner releasability of the thin layer regulating member by including at least the above material on the surface.

Such a polyimide-modified silicone resin can be produced by using a mixture of siloxane diamine, aromatic diamine and tetracarboxylic dianhydride as a raw material.

As the siloxane diamine compound, H2
N-R1-(-SiR2R3-O-) n-SiR4R5
-R6-NH2 (R1 and R6 are divalent organic groups, R2-R
5 represents an alkyl group, a phenyl group, or a substituted phenyl group, and n represents an integer of 5 to 50) is shown as a general formula, and specifically, bis (3-aminopropyl) tetramethyldisiloxane, bis (10-aminodecamethylene)
Examples thereof include tetramethyldisiloxane, dimethylsiloxane tetramer having an aminopropyl terminal group, octamer, and bis (3-aminophenoxymethyl) tetramethyldisiloxane.

As the aromatic diamine, for example, (1)
Biphenyl-based diamine compound, diphenylether-based diamine compound, benzophenone-based diamine compound, diphenylsulfone-based diamine compound, diphenylmethane-based diamine compound, diphenylalkane-based diamine compound such as 2,2-bis (phenyl) propane, 2,2-bis (phenyl ) Hexafluoropropane-based diamine compounds, diphenylene sulfone-based diamine compounds, (2) di (phenoxy) benzene-based diamine compounds, di (phenyl) benzene-based diamine compounds, (3) di (phenoxyphenyl) hexafluoropropane-based diamines Aromatic diamine mainly containing "aromatic diamine compound having two or more aromatic rings (benzene ring etc.) such as bis-type compound, bis (phenoxyphenyl) propane-based diamine-based compound" It can be mentioned, they may be used alone or as a mixture.

As the aromatic diamine, in particular,
Diphenyl ether-based diamine compounds such as 4-diaminodiphenyl ether and 1,3-diaminodiphenyl ether, 1,3-di (4-aminophenoxy) benzene,
Di (phenoxy) benzene-based diamine compounds such as 1,4-bis (4-aminophenoxy) benzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- ( Examples thereof include bis (phenoxyphenyl) propane-based diamine compounds such as 3-aminophenoxy) phenyl] propane.

As the tetracarboxylic dianhydride, pyromellitic dianhydride as the tetracarboxylic dianhydride,
3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic Acid dianhydride, 2,3 ', 3,4'-
Biphenyl tetracarboxylic dianhydride, bis (3,4-
Dicarboxyphenyl) ether dianhydride, 4,4'-
Bis (3,4-dicarboxyphenoxy) diphenyl sulfone dianhydride, ethylene glycol bis trimellitate dianhydride, 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 4 , 4 '
-Diphenylsulfone tetracarboxylic dianhydride, 3,
3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,3', 3,4'-biphenyltetracarboxylic dianhydride, etc. are mentioned.

The polyimide-modified silicone resin used in the present invention can be produced by a known method using the above compounds. For example, these are heated in an organic solvent in the presence of a catalyst such as tributylamine, triethylamine, triphenyl phosphite, etc., if necessary, to directly obtain a polyimide, tetracarboxylic dianhydride and diamine in an organic solvent. After reacting to obtain a polyamic acid that is a precursor of polyimide, a dehydration catalyst such as p-toluenesulfonic acid is added if necessary, and imidization is performed by heating to obtain a polyimide, or this polyamic acid. , Acetic anhydride, propionic anhydride, acid anhydrides such as benzoic anhydride, dehydration ring-closing agents such as carbodiimide compounds such as dicyclohexylcarbodiimide, and pyridine, isoquinoline, imidazole, by adding a ring-closing catalyst such as triethylamine as necessary. , There are methods such as chemical ring closure.

At least the surface of the thin layer regulating member of the present invention needs to be formed of a polyimide-modified silicone resin, and can be appropriately mixed with other organic or inorganic materials and used as necessary. These examples will be described below.

(1) Addition of Resistance Control Agent The thin layer regulating member of the present invention is made conductive so that a bias electric field is applied between the developing rollers to control the charge amount distribution of the toner, especially the amount of the oppositely charged toner. Can be reduced. FIG. 3 shows the case of negatively charged toner as an example. In this case, the reversely charged toner, that is, the positive toner, is captured by the bias electric field on the thin layer regulating member side, and the amount of the positive toner is reduced after passing through the thin layer regulating member. To make the bias electric field effective, the volume resistance of the layer containing the polyimide-modified silicone resin of the thin layer regulating member should be 10 ¹² Ω · cm.
It is necessary to do the following. Volume resistance is 10 ¹² Ω ・ c
When it exceeds m, the effect of the bias electric field becomes insufficient,
The bias electric field cannot reduce the amount of reversely charged toner. Further, when the layer structure of the thin layer regulating member has not only a single layer of the polyimide-modified silicone resin of the present invention but also a plurality of layers, it is necessary that the electric resistance other than the surface layer is also controlled to be sufficiently conductive.

The resistance controlling agent used in the thin layer regulating member of the present invention may be a usual one. For example, carbon black such as Ketjen black or acetylene black or Ni
Metal fine powder such as powder, metal oxide such as titanium oxide and zinc oxide, organic compound containing quaternary ammonium salt group, carboxylic acid group, sulfonic acid group, sulfuric acid ester group, phosphoric acid ester group, or the like, or Organic charging such as polymer, ether ester amide or ether amide imide polymer, ethylene oxide-epihalohydrin copolymer, compound having a conductive unit typified by methoxypolyethylene glycol acrylate or organic antistatic agent such as polymer compound Examples thereof include inhibitors.

(2) Addition of Charge Control Agent The thin layer regulating member of the present invention can improve the charge characteristics of the toner by adding a charge control agent suitable for the charge polarity of the toner. For example, as the charge control agent used for the positively chargeable toner, a metal complex salt dye represented by an azo-chromium complex salt dye, a hydroxybenzoic acid derivative or an aromatic dicarboxylic acid, a metal complex salt compound or a metal salt of an anthranilic acid derivative is used. Compounds, organoboron compounds and biphenol compounds or oligomer types.

Since the polyimide-modified silicone resin used in the present invention contains a siloxane component in its structure,
It is slightly negatively charged in the triboelectric series. Therefore,
When a negatively chargeable toner is used, it is particularly effective to add a positively chargeable charge control agent to increase the toner chargeability. The positively chargeable charge control agent means that the polyimide-modified silicone resin is located on the positively chargeable side in the triboelectric charging series. Charge polarity (and charge potential)
Can be easily determined by measuring with a surface electrometer. For example, when the material used is a polymer, a roller provided with a polyimide-modified silicone resin on the surface is used as shown in FIG.
It can be determined by setting the developing device typified by No. 1), rotating it in sliding contact with a blade coated or pasted with the material to be used on the surface, and measuring the charging polarity (potential) of the roller. At that time, other members are not brought into sliding contact with the developing roller such as the toner and the supply roller. Also, in the case of powder or liquid, after adding the material to the cyclic polyolefin used for the developing roller and setting it on the blade surface, it is possible to know by measuring the roller charging polarity in the same manner as the above method. it can. Examples of charge control agents that are preferably used for negatively chargeable toners include azine dyes typified by nigrosine, basic dyes typified by triphenylmethane dye, and laked pigments of basic dyes. Examples thereof include metal complex dyes in which a quaternary ammonium residue is introduced into the mother skeleton.

A particularly preferred charge control agent is represented by the following formula (2)
And (3) are representative examples of the quaternary ammonium salt group-containing maleimide resin and the quaternary ammonium salt group-containing methacrylimide resin. This is characterized by not only exhibiting an excellent positive charging property by containing quaternary ammonium, but also having electrical conductivity in electrical characteristics. Further, since it is an imide-based material similar to the polyimide-modified silicone resin used in the present invention, it has affinity and can be suitably used as an organic conductive agent. By using these materials, it is possible to uniformly control the conductivity without variations in resistance.

Maleimide resin containing quaternary ammonium salt group

[Chemical 2] Methacrylimide resin containing quaternary ammonium salt group

[Chemical 3] It is preferable to add 1 to 100 parts by weight of the above materials to 100 parts by weight of the polyimide-modified silicone resin. If the addition amount is less than 1 part by weight, the toner charge amount is not sufficiently improved, and if it exceeds 100 parts by weight, the toner releasability is deteriorated and toner sticking occurs, which is not preferable.

In the layer containing at least the polyimide-modified silicone resin of the present invention, various organic and inorganic materials may be mixed, if necessary, in addition to the resistance control agent and the charge control agent. Other organic resin materials that can be mixed include alkyd resin, chlorinated polyether, chlorinated polyethylene, epoxy resin, fluororesin, phenol resin,
Examples thereof include polyamide, polycarbonate, polyethylene, methacrylic resin, polypropylene, polystyrene resin, polyurethane, polyvinyl chloride, polyvinylidene chloride and silicone resin. These may be dissolved in a solvent and used, or one of them may be mixed and used in the form of resin fine particles.

Next, the form of the thin layer regulating member of the present invention will be described. FIG. 5A illustrates the thin layer regulating member in the shape of a blade, which abuts in the forward direction and the reverse direction according to the rotation direction of the developing roller. Figure 5-2
Is a roller-shaped thin layer regulating member, FIG.
FIG. 5-4 shows a belt shape. All of these need to have a layer containing at least a polyimide-modified silicone resin formed at least in a portion in contact with the developing roller, and if necessary, a single layer or a plurality of layers may be formed as a lower layer. Particularly, when the thin layer regulating member has flexibility, the uniform stability of the thin toner layer on the developing roller is improved. At this time, the form of the developing roller is not limited, but if the developing roller is a rigid body and the thin layer regulating member has flexibility, the thin layer regulating member comes into closer contact with the toner layer, so that this effect is more remarkable. Become. Since the polyimide-modified silicone resin of the present invention contains a silicone component and is flexible, it can be used without cracking even when formed on the elastic layer. The rubber hardness of the elastic layer is JIS A 80 °
Hereinafter, the layer thickness is preferably 0.5 mm or more. J
When the IS A exceeds 80 ° or falls below 0.5 mm, rubber elasticity is not sufficiently exerted, and the above effect cannot be obtained.

As the material for the elastic layer, a general material can be used. For example, polyurethane, butyl rubber,
Examples thereof include nitrile rubber, epichlorohydrin rubber, polyisoprene rubber, polybutadiene rubber, silicone rubber, fluororubber, styrene-butadiene rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, chloroprene rubber, acrylic rubber and mixtures thereof. . Most of these rubber materials are usually
Although it is insulative, when the bias voltage is applied as described above, it is possible to add the above-mentioned resistance control agent and use it as a conductive material.

In the form of the thin layer regulating member of the present invention described above, in addition to fixing and using the contact portion with the developing roller, it is intermittently rotated and moved by the external drive means during standby to contact. It is preferable to change the site. Since the abutting portions are not constant, local abrasion can be prevented, and in particular, minute particles such as paper, plastic, sponge, foreign matter, and agglomerates existing in the image forming apparatus typified by a copying machine are used in the developing device. This is effective because it is possible to prevent thin layer streaks and the like that are generated when the particles are mixed in and move inside and are retained at the contact portion between the developing roller and the thin layer regulating member. In this case, the direction of rotation and movement of the thin layer regulating member is the same as the direction in which foreign matter, aggregates, etc. are discharged out of the system, that is, the rotation direction of the developing roller. The driving means can be provided separately. It is desirable to use the follow-up rotation due to the sliding friction with the developing roller because the cost can be reduced, but if the surface is slippery, reliable rotation cannot be expected, and therefore the surface property must be controlled.

According to the present invention, the surface friction coefficient of the thin layer forming member is controlled to 0.2 to 0.7 or less to prevent slippage, and the thin layer regulating member can be reliably rotated and moved. If the surface friction coefficient is less than 0.2, there is almost no entrainment, and it is difficult to remove foreign matter, aggregates, etc., and if it exceeds 0.7, toner filming on the surface of the thin layer regulating member occurs, which is not preferable.

The surface friction coefficient referred to in the present invention is measured by the Euler belt method used for measuring a cylindrical body, and a typical measuring device is shown in FIG. This will be explained briefly. The support base 132 is fixed on the base 131, and the photoreceptor 1 is fixedly supported thereon. A paper tape 133 having a width of 30 mm is hung on the peripheral surface of the photoconductor 1, a weight W of 100 g is attached to one end, and the other end is hung on the hook 135 of the force gauge 134. The body 136 of the force gauge 134 is slidably mounted on the base 131. Here, when the force gauge 134 is pulled in the direction of arrow C, first, the main body 136 thereof starts to move in this direction. If you gradually increase the pulling power, this time,
The paper tape 133 connected to the main body 136 via the hook 135 starts to be pulled in the direction of arrow C while sliding on the peripheral surface of the photoconductor 1 which is immovably fixed. The pulling force (maximum static friction force) F at this time is measured by the force gauge 134, and the surface friction coefficient is calculated.

In order to control the surface friction coefficient, ordinary general inorganic fillers, organic particles and the like can be used. Examples of the inorganic filler include zinc oxide (ZnO), tin oxide (SnO ₂ ), indium oxide (In ₂ O ₃ ), titanium oxide (TiO ₂ ), metal oxides such as silica, alumina, and zirconia. . Further, other than these, metals, silicon compounds, carbon, carbon compounds, fullerenes, boron compounds, carbides, nitrides, silicides, ceramics, chalcogen compounds and the like can be preferably used. The organic particles and the like described above can also be preferably used. The particle size of these inorganic fillers must be 1 μm or less,
If it exceeds 1 μm, the toner is fixed and filming occurs.

Next, a method of manufacturing the thin layer regulating member of the present invention will be described. (1) Method of dissolving and coating in solvent to form thin layer roller after dissolving in solvent can be carried out according to a conventional method. For example, a liquid obtained by dissolving or dispersing each component described above in a solvent. It can be carried out by casting the composition on a suitable carrier (support), and then removing the solvent by drying. There is no particular limitation on the carrier, and those used in a general solution casting method are used, and examples thereof include metal rollers such as SUS and Al, conductive resin rollers, rubber rollers, plate-shaped structures, sheets and belts. Etc. can be mentioned. As the solvent, for example, N
-Methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, sulfolane, hexamethylphosphoric triamide,
1,3-Dimethyl-2-imidazolidone, hexane, benzene, toluene, xylene, methyl ethyl ketone, acetone, diethyl ether, tetrahydrofuran, dioxane, 1,2-dimethoxymethane, diethylene glycol dimethyl ether, methyl cellosolve, cellosolve acetate, methanol, ethanol, propanol ,
Examples include isopropanol, methyl acetate, ethyl acetate, acetonitrile, methylene chloride, chloroform, carbon tetrachloride, chlorobenzene, dichlorobenzene, dichloroethane, trichloroethane, etc., and the type and amount are appropriately selected so that each component is dissolved and dispersed. Select and use.

The concentration of the polyimide-modified silicone resin in the solvent is appropriately selected according to the film thickness to be produced, but is usually 0.1 to 60% by weight, preferably 1 to 50% by weight, more preferably 5 to 45%. It is in the range of% by weight. When the concentration of the cyclic olefin-based polymer is in this range, the thickness of the film can be easily adjusted and the film-forming property is excellent, which is preferable.
The method of casting the liquid composition on a carrier is not particularly limited, but, for example, a doctor knife, a meer
It can be performed using a bar, a roll coat or the like. The liquid composition can be cast by spraying, brushing, rolling, spin coating, dipping or the like. 1
When the desired film thickness cannot be obtained by one-time coating, the coating can be repeated.

(2) Method of Dissolving in Solvent and Forming Endless Belt A resin solution dissolved in an appropriate concentration by the same method as described above is applied to the inner surface of the cylindrical molding die rotating at high speed shown in FIG. It is a method of forming an endless film (sheet) while uniformly spreading the resin liquid by its centrifugal force. "1 is type, 2
Is a molded film or cured film, 10a is a rotation support part, 10b is a support part, and 10c is a heater. That is, a base is put into the mold by coating or pouring, and the mold 1 is rotated at a high speed at a predetermined rotation speed to mold a molding film 2 having a predetermined thickness inside the mold 1. In order to finally finish the molded film 2 obtained by centrifugal molding into an endless belt, it is necessary to dry the molded film 2 at a predetermined temperature and then peel it from the mold.

[0051]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

Example 1 [Component for forming surface layer of thin layer regulating member] Polyimide-modified silicone resin (X-22-8917; Shin-Etsu Chemical Co., Ltd.) 100 parts by weight Cyclohexanone 100 parts by weight Methyl ethyl ketone 100 parts by weight The above coating liquid was applied to a SUS plate (0 0.1 mm thick), and left in a constant temperature bath at 200 ° C. for 1 hour to prepare a sample plate (film thickness 20 μm).

[Evaluation of Thin Layer Controlling Member] A toner releasability test sample plate was brought into contact with toner (Ricoh cyan toner, type 4100) as shown in FIG. / Cm ² , 50 ° C, 1 hour under the conditions of heating and pressurization. After the test, the toner was blown off with 3 kg / cm ² of air, and the toner residual state was evaluated by the following visual rank.

[0054] [Release rank]     Rank 8 Toner is very easily removed.           7 The toner is completely removed although it takes some time.           6 A slight amount (less than several%) of toner remains.           About 5% to 1/3 of the toner remains.           About 1/3 to 2/3 of toner remains.           32/3 or more toner remains.           2 Toner remains on the entire surface (present as toner particles).           1 Toner remains on the entire surface.               (They do not exist as toner particles and the particles fuse together)

Abrasion test Taber abrasion tester (Rotary Abrasion)
A test plate was attached to Tester; manufactured by Toyo Seiki Co., Ltd., and the amount of wear was determined from the weight difference before and after the test (wear wheel; CS-5 manufactured by Toyo Seiki, pressure: 1 kg, rotation speed: 60 rpm.300).
0 revolutions).

Idling test The device was mounted on the developing device shown in FIG. 1 and a idling test was carried out for 100 hours. The following members were used for each member of the developing device. Toner Ricoh cyan toner Type 4100 Development roller Two-layer structure: Carbon black added Nitrile butadiene rubber Electroconductive elastic layer / Fluorine resin surface layer Supply roller Conductive urethane sponge Linear speed Development roller = 100 mm / sec, Supply roller = 120 mm / sec Potential development Roller = ground, supply roller = −150 V, thin layer regulating member = floating toner is in a thin layer state during idling, toner is adhered to the developing roller abutting portion of the thin layer regulating member and its periphery after abrasion, abrasion state, etc. Was observed.

Example 2 The polyimide-modified silicone resin (X-
22-8917) is a polyimide-modified silicone resin (X
-22-8904; Shin-Etsu Chemical Co., Ltd.), a sample was prepared in the same manner as in Example 1, and the same evaluation was performed.

Example 3 [Synthesis of Polyimide-Modified Silicone Resin] A four-necked flask equipped with a dry nitrogen gas inlet tube, a condenser, a thermometer, and a stirrer was dehydrated and refined into N-methyl-2-pyrrolidone (NM).
P) 791 g, 10 minutes while flowing nitrogen gas,
After vigorous stirring, 2,2-bis (4- (4-aminophenoxy) phenyl) propane (BAPP) 0.10 m
ol, diaminopolydimethylsiloxane (X-22-1
61AS; Shin-Etsu Chemical Co., Ltd.)
Heat to 0 ° C. and stir until uniform. Next, the system is cooled to 5 ° C. or lower in an ice-water bath, and trimellitic anhydride 0.42 is added.
mol was added, and then stirring was continued for 3 hours. During this period, the flask was kept at 5 ° C or lower. Then, the nitrogen gas introducing tube and the condenser were removed, a Dean-Stark tube filled with xylene was attached to the flask, and 198 g of xylene was added to the system. Instead of the oil bath, the system was heated to about 175 ° C., and the generated water was removed from the system. After heating for 4 hours and generation of water from the system was not observed, the system was cooled and the reaction solution was poured into a large amount of methanol to precipitate a resin.
After the solid content was filtered, the solvent was removed by drying under reduced pressure at 80 ° C. for 12 hours to obtain a silicone-modified polyimide resin A. Using the obtained resin A, a sample was prepared in the same manner as in Example 1, and the same evaluation was performed.

Comparative Example 1 [Components for forming surface layer of thin layer regulating member] Polyimide resin (Upilex S: Ube Industries, Ltd.) 100 parts by weight N-methyl-2pyrrolidone 500 parts by weight In the same manner as in Example 1 using the above materials. Make a sample,
Similar evaluation was performed.

Comparative Example 2 [Surface Layer Forming Component for Thin Layer Controlling Member] Silicone Resin (SR2411; Toray Silicone) 100 parts by weight Toluene 100 parts by weight A sample was prepared in the same manner as in Example 1 using the above materials,
Similar evaluation was performed.

Comparative Example 3 [Surface Layer Forming Component for Thin Layer Controlling Member] Epoxy-modified silicone resin (SR2115; Torre silicone) 100 parts by weight Aminosilane coupling agent (SH6020; Torre silicone) 5 parts by weight Toluene 100 parts by weight Using the above materials , Prepare a sample in the same manner as in Example 1,
Similar evaluation was performed. The above results are shown in Table 1.

[0062]

[Table 1]

Example 4 [Component for forming surface layer of thin layer regulating member] Polyimide-modified silicone resin (X-22-8904; Shin-Etsu Chemical Co., Ltd.) 100 parts by weight Cyclohexanone 100 parts by weight Methyl ethyl ketone 100 parts by weight Carbon black (Black Pearl L; Degussa) 0, 15, 22, 30, 45 parts by weight The above-mentioned carbon black was added to the surface layer forming component used in Example 1, and the mixture was ball-milled for 72 hours. A sample was prepared in the same manner as in Example 1, and the volume resistance and the amount of the oppositely charged toner were measured. The volume resistance was calculated from the resistance value after 1 minute at 100 V DC using the following formula. Volume resistance R (Ω · cm) = (resistance measurement value R ′) × (main electrode area cm ² / film thickness cm)

Regarding the amount of reversely charged toner, a thin layer regulating member was similarly mounted on the developing device used in Example 1, and an endless belt photosensitive member (not shown) was brought into contact with the developing device. Next, development is performed under the following bias conditions in which the bias potential conditions of the developing roller and the thin-layer regulating member are changed, the toner on the photoconductor after development is tape-transferred, and this is attached to a blank paper, and the image density is measured. (Measuring device; X-Rite 938 Spectrodensi
tometer). The density of the blank was also measured, and the difference was used as the index value ΔID of the amount of reversely charged toner. Bias condition 1: photoconductor 0V, developing roller + 450V,
Thin layer regulating member + 450V Bias condition 2: photoconductor 0V, developing roller + 450V,
FIG. 9 shows the relationship between the thin layer regulating member + 300V carbon black addition amount and the volume resistance, and FIG. 10 shows the relationship between the volume resistance and ΔID.

[0065] Examples 5-9 [Thin layer regulating member surface layer forming component]     Polyimide modified silicone resin       (X-22-8904; Shin-Etsu Chemical Co., Ltd.) 100 parts by weight     Cyclohexanone 100 parts by weight     Methyl ethyl ketone 100 parts by weight     Positive charge control agent 5 parts by weight

A positive charge control agent shown in Table 2 was added to the surface layer forming component of Example 2, and a thin layer regulating member was produced by the same method as described above. When this was subjected to sliding friction with the one prepared in the same manner and containing no positive charge control agent by the above-mentioned method, the charge polarity of all those containing a positive charge control agent was positive. Further, as in Example 1, the toner was attached to the developing device, and the toner charge amount (q / m) and the adhesion amount (m / m)
a) was measured. m / a is 0.4 to 0.5 mg / cm ²
At the level of, q / m is preferably −25 ± 10 μc / g,
The closer to the center value is more preferable.

The results are shown in Table 2.

[Table 2]

Example 10 [Component for forming surface layer of thin layer regulating member] Polyimide-modified silicone resin (X-22-8904; Shin-Etsu Chemical Co., Ltd.) 100 parts by weight Cyclohexanone 100 parts by weight Methyl ethyl ketone 100 parts by weight Quaternary ammonium salt group-containing maleimide resin 5 10, 15, 25, 45 parts by weight A thin layer regulating member was prepared in the same manner as in Example 1 and Example 4
The volume resistance and ΔID (reversely charged toner) were measured in the same manner as in, and the toner charge amount and the adhesion amount were measured in the same manner as in Examples 5 to 9. The results are shown in Table 3.

[0069]

[Table 3]

Example 11 Nitrile butadiene rubber (NBR) was used to form a rubber layer having a thickness of 4
mm, rubber hardness JISA 60 °, and a rubber roller having a diameter of 12 mm was produced. Next, the same material as in Example 2 was used to form a surface layer (film thickness: 15 μm) by spray coating. This was mounted on the developing device shown in FIG. Each member used in the developing device is A instead of an elastic roller as a developing roller.
The same one as in Example 1 was used except that the L developing roller was used (the thin layer regulating member was fixed). In order to evaluate the stability of the toner thin layer of this thin layer regulating member, a free running test for 100 hours was conducted. As a result, no streaks and the like were generated in the toner thin layer, and a uniform toner thin layer was stably obtained. .

Example 12 The developing device used in Example 11 was changed in mechanism so that it could be rotated in the direction of rotation of the developing roller intermittently along with the developing roller. Developing roller 60 seconds rotation →
A idling test for 100 hours of developing roller cumulative driving was performed by a driving program of 4.8 seconds rest → rotation of developing roller for 0.4 seconds, rotation with thin layer roller → 4.8 seconds rest. A small piece of copy paper was intentionally mixed into the developing device every 10 hours for free running to evaluate the uniform stability of the thin toner layer, but no uniform streaks were generated and a uniform thin layer was obtained. Next, similarly to the conventional method, when the thin layer roller was fixed and the thin layer formation at the time of mixing minute pieces of copy paper was observed, a streak was generated in the toner thin layer about 10 minutes after mixing. When the developing device was disassembled and the contact portion with the developing roller was observed, it was confirmed that minute pieces were present at the streak-generating location. As described above, it was confirmed that the present developing device can cope with an unexpected situation where foreign matter is mixed.

Example 13 [Components for forming surface layer of thin layer regulating member] Polyimide-modified silicone resin (X-22-8904; Shin-Etsu Chemical Co., Ltd.) 100 parts by weight Cyclohexanone 100 parts by weight Methyl ethyl ketone 100 parts by weight The particles shown were added and the surface friction coefficient was measured by the Euler belt method described above. Next, the same driving program as in the twelfth embodiment is used to perform 100
An idle test was conducted. The results are shown in Table 4.

[0073]

[Table 4]

Example 14 The developing device used in Example 11 was mounted on the image forming apparatus shown in FIG. A continuous copying test of 100,000 sheets was carried out while rotating the thin layer regulating member 1/4 rotation along with the developing roller during non-copying once every 300 sheets, and the toner thin layer state was uniform and stable. Met. In addition, there was no background stain due to generation of the oppositely charged toner, and a good image was stably obtained.

[0075]

According to the present invention, the toner of the thin layer regulating member is excellent in releasability and abrasion resistance, has little reverse charging, and is stable without streaks occurring in the toner thin layer due to the inclusion of foreign matters. A developing device that can form a thin toner layer is provided, and an image forming device that can obtain a high-quality and highly durable image using the developing device is provided. The contribution to the field of formation is extremely large.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a non-magnetic one-component developing device used in a copying machine.

FIG. 2 is a schematic view showing an image forming apparatus according to the present invention.

FIG. 3 is a diagram showing a toner transfer state.

FIG. 4 is a diagram showing a state in which foreign substances and agglomerates are mixed in the developing device.

FIG. 5 is a diagram showing a shape aspect of a thin layer regulating member.

FIG. 6 is a diagram showing an apparatus for measuring a surface friction coefficient of a thin layer regulating member.

FIG. 7 is a view showing a cylindrical molding die that rotates at high speed when forming an endless belt.

FIG. 8 is a view showing a simple press molding machine for a laboratory.

FIG. 9 is a diagram showing the relationship between the amount of carbon black added and the volume resistance.

FIG. 10 is a diagram showing a relationship between volume resistance and ΔID.

FIG. 11 is a diagram showing a developing device used in Example 11;

[Explanation of symbols]

(In Figure 2) 1 photoconductor 2 Static elimination circuit high part 3 electrified naja 4 Eraser 5 Image exposure unit 6 Development device 7 Charger before transfer 8 Registration roller 9 Transfer paper 10 Transfer charger 11 Separation Charger 12 separate nails 13 Charger before cleaning 14 fur brush 15 cleaning brush (In FIG. 6) 1 photoconductor 131 support 132 paper tape 134 Force Gauge 135 hook 136 body (In FIG. 7) Type 1 2 Molded film or cured film 10a rotation support part 10b support 10c heater

Claims (8)

[Claims] 1. A developing roller that moves while carrying toner on the surface and conveys the toner onto an image bearing member, and a developing roller that is in contact with the developing roller via the toner carried on the developing roller and has a toner thickness And a thin layer regulating member for regulating the latent image on the image carrier using the toner conveyed by the developing roller. A developing device, the surface of which is formed of a material containing a polyimide-modified silicone resin. 2. The volume resistance of the layer formed of the material containing the polyimide-modified silicone resin is 10 ¹² Ω · c.
The developing device according to claim 1, wherein the developing device has a thickness of m or less. 3. The thin layer regulating member according to claim 1, wherein when the toner is a negatively charged toner, the thin layer regulating member contains a material positioned on the positively charged side in the triboelectric charging series with respect to the polyimide-modified silicone resin. Developing device. 4. A resin component 1 for forming a surface layer, wherein the thin layer regulating member comprises a quaternary ammonium salt-containing maleimide resin and / or a quaternary ammonium salt-containing methacrylimide resin.
The developing device according to claim 1, wherein the developing device contains 15 parts by weight or more with respect to 00 parts by weight. 5. The thin layer regulating member comprises a plurality of layers,
The developing device according to any one of claims 1 to 4, wherein an elastic layer is provided in a layer other than a surface layer formed of a material containing at least the polyimide-modified silicone resin. 6. The developing device according to claim 1, wherein the thin layer regulating member operates in an interleaving direction in the rotation direction of the developing roller. 7. The surface friction coefficient of the thin layer regulating member is 0.
The developing device according to claim 1, wherein the developing device has a density of 2 to 0.7. 8. An image forming apparatus comprising at least a charging means, an exposing means, a developing means, a transferring means, a cleaning means, a charge removing means, and an electrophotographic photosensitive member, wherein the developing means is one of claims 1 to 7. An image forming apparatus using the developing device according to any one of claims.