JP2001075354A - Developer carrying member and image forming device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the adhesion property of a conductive elastic base material and a resin coating layer and to prevent the cracking of the resin coating layer in long-term use by providing the surface of the conductive elastic base material with the specific resin coating layer. SOLUTION: The developer carrying member 1 is constituted by forming the conductive elastic layer 3 on the outer side of a good conductive shaft 2 or the like and further, forming the resin coating layer 4 at need on its surface. The conductive elastic layer 3 is required to satisfy the equation 0.01<=S.T/D<=2.0, where S denotes a compression set (%), T denotes a thickness (mm) and D denotes Asker C hardness ( deg.). In this case, S.T/D is preferably 0.02<=.T/D<=1.5 and further preferably 0.025<=S.T/D<=1.0. The preferable Asker C harness of the conductive elastic layer 3 ranges from 30 to 80 deg., more particularly preferably from 40 to 70 deg.. The thickness of the conductive elastic layer 3 is preferably 1 to 5 mm, more particularly preferably 2 to 4 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer carrier and an image forming apparatus, and more particularly, to an image forming apparatus such as a copying machine or a printer. To form a visible image on the surface of the image forming body, and when the developer carrier and the contact member such as a layered blade are brought into close contact or contact with each other, the developer carrier comes into contact with the developer carrier. The present invention relates to a developer carrier that can prevent generation of marks and does not cause an image defect when used in an image forming apparatus, and an image forming apparatus equipped with the same.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus such as a copying machine or a printer, a one-component toner is supplied to an image forming body such as a photoconductor holding an electrostatic latent image.
As an image forming method for visualizing the toner by attaching the toner to the latent image, a pressure development method is known (US Pat.
No. 152012, No. 3731146). In this pressure development method, a toner carrier (developer carrier) carrying toner is brought into contact with an image forming body (photoconductor) holding an electrostatic latent image, and the toner is transferred to the latent image on the image forming body. An image is formed by attaching the toner carrier to an image. Therefore, the toner carrier needs to be formed of a conductive elastic material having conductivity and elasticity.

FIG. 2 is a schematic diagram showing an example of an image forming apparatus using the pressure development method. In the pressure development method, as shown in FIG. To supply: A developer (toner) carrier (developing roller) 1 is disposed between a developer (toner) applying roller 5 and an image forming body (photoconductor) 6 holding an electrostatic latent image. Then, the toner 7 is supplied to the surface of the toner carrier 1 by the toner applying roller 5 by rotating the toner carrier 1, the image forming body 6 and the toner applying roller 5 in the direction of the arrow in FIG. The toner is arranged in a uniform thin layer by the layering blade 8. Then, in this state, the toner carrier 1 rotates while being in contact with the image forming body 6, so that the toner formed in a thin layer adheres to the latent image of the image forming body 6 from the toner carrier 1, and The latent image is made visible. In the figure, reference numeral 9 denotes a transfer unit, which transfers a toner image to a recording medium such as paper. Reference numeral 10 denotes a cleaning unit, which is installed as necessary, and the cleaning blade 11 removes toner remaining on the surface of the image forming body after transfer.

In such an image forming apparatus using the pressure development method, the toner carrier 1 must rotate while maintaining a state in which it is in close contact with the image forming body 6. Therefore, the schematic sectional view of FIG. As shown in FIG. 2, on the outer periphery of the shaft 2 made of a good conductive material such as metal, silicone rubber, NBR (acrylonitrile-butadiene copolymer rubber), EPDM (ethylene-propylene-diene copolymer rubber), polyurethane rubber, etc. It has a structure in which a conductive elastic layer 3 made of a conductive elastic body provided with conductivity by blending a conductive agent into elastic rubber or foam is formed. Further, if necessary, for controlling the chargeability and adhesion of the developer 7, or for controlling the frictional force between the image forming body 6 and the layering blade 8 and for preventing the photosensitive member from being contaminated by the elastic body. A coating layer 4 made of resin or the like is provided on the surface of the conductive elastic layer 3. On the other hand, an image forming method in which a developer carried on a developer carrying member is directly flown on an image forming body made of paper sheets such as paper or OHP paper via a hole-shaped control electrode to form an image. Has also been proposed. Further, a non-magnetic developer layered in a thin layer is carried on the surface of a sleeve-like developer carrier disposed in a non-contact state in proximity to the image forming body (photoconductor), and this is placed on the photoconductor. A method of forming an image by developing the image by flying the image is also proposed (JP-A-58-116559).

However, when the above-described toner carrier is used in an image forming apparatus, horizontal streaks may occur on the image at a constant cycle depending on the use condition.
It is presumed that the cause is a contact mark on the surface of the toner carrier by a contact member such as a stratified blade contacting the toner carrier. Also, in order to reduce this contact mark,
It is known that the compression set of the elastic body forming the toner carrier needs to be lower than a certain value.

[0006]

SUMMARY OF THE INVENTION In the present invention, in such a situation, in a developer carrier having a conductive elastic base layer, the developer carrier and a contact member such as a layered blade are brought into close contact or contact. In this case, it is possible to prevent the occurrence of contact marks on the developer carrying member, and to prevent the occurrence of an image defect when used in the image forming apparatus, and to mount the developer carrying member. It is an object of the present invention to provide an image forming apparatus according to the present invention.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to achieve the above object, and as a result, have found that the permanent compression set S (%) and the thickness T of the conductive elastic layer of the developer carrying member. (Mm)
Also, it has been found that a developer carrier having an Asker C hardness D (°) satisfying a specific relational expression can be suitable for the purpose. The present invention has been completed based on such findings. That is, the present invention has a conductive elastic layer, carries a developer on the surface, forms a thin film thereof, and supplies or supplies the developer to the surface of the image forming body in contact with or close to the image forming body. Thereby, in the developer carrier that forms a visible image,
The conductive elastic layer has a relational expression (I) 0.01 ≦ S · T / D ≦ 2.0 (I) [where S is compression set (%), T is wall thickness (mm),
D indicates Asker C hardness (°). ] Is provided. Further, the present invention provides a developing method for forming a visible image by carrying a developer on the surface to form a thin film thereof, and contacting or approaching the image forming body and supplying the developer to the surface of the image forming body. The present invention also provides an image forming apparatus equipped with a developer carrier, wherein the developer carrier is used as the developer carrier.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The conductive elastic layer referred to in the present invention is:
Refers to a conductive elastic layer provided outside the shaft or the like. As shown in FIG. 1 described above, the developer carrier of the present invention has a conductive elastic layer 3 formed on the outside of a good conductive shaft 2 and the like, and a resin coating layer 4 formed on the surface thereof as required. It is. For the conductive elastic layer, an elastic material obtained by adding a conductive agent to an appropriate rubber-like elastic body to impart conductivity is used. Here, there is no particular limitation on the rubber-like elastic body,
It can be arbitrarily selected from those conventionally used in developer carriers. Examples of the rubbery elastic body include nitrile rubber, ethylene propylene rubber, ethylene propylene diene rubber, styrene butadiene rubber, butadiene rubber, isoprene rubber, natural rubber,
Examples include silicone rubber, urethane rubber, acrylic rubber, chloroprene rubber, butyl rubber, epichlorohydrin rubber, and silicone rubber. These may be used alone or in combination of two or more. Among them, nitrile rubber, urethane rubber, epichlorohydrin rubber, ethylene propylene rubber, ethylene propylene diene rubber, and silicone rubber are particularly preferable. is there.

As the conductive agent, an ionic conductive agent or an electronic conductive agent is used. Examples of the ion conductive agent include tetraethylammonium, tetrabutylammonium,
Perchlorates, chlorates, hydrochlorides, bromine such as dodecyltrimethylammonium (eg, lauryltrimethylammonium), hexadecyltrimethylammonium, octadecyltrimethylammonium (eg, stearyltrimethylammonium), benzyltrimethylammonium, modified fatty acid dimethylethylammonium Acid salt,
Ammonium salts such as iodate, borofluoride, sulfate, ethyl sulfate, carboxylate and sulfonate; and perchlorine of alkali metals and alkaline earth metals such as lithium, sodium, potassium, calcium and magnesium Acid, chlorate, hydrochloride, bromate, iodate,
Borofluoride, trifluoromethyl sulfate, sulfonate and the like can be mentioned. Examples of the electron conductive agent include conductive carbon such as Ketjen black and acetylene black; SAF, ISAF, HAF, FEF, and the like.
Rubber carbon such as GPF, SRF, FT, and MT; carbon for oxidation-treated ink, pyrolytic carbon, and graphite; conductive metal oxides such as tin oxide, titanium oxide, and zinc oxide; metals such as nickel and copper And the like.

[0010] These conductive agents may be used alone or in combination of two or more. The amount of addition is not particularly limited, but in the case of the ionic conductive agent, usually 0.01 to 5 parts by weight, preferably 0.05 to 2 parts by weight, based on 100 parts by weight of the rubber-like elastic body. Selected by range. On the other hand, in the case of the electronic conductive agent, it is selected in the range of 1 to 50 parts by weight, preferably 5 to 40 parts by weight, based on 100 parts by weight of the rubber-like elastic body. Thereby, the resistance value of the conductive elastic layer is
It is preferable to adjust to a range of 10 ³ to 10 ¹⁰ Ω · cm, and particularly preferable to adjust to a range of 10 ⁴ to 10 ⁸ Ω · cm. Note that, in addition to the conductive agent, other rubber additives such as a known filler and a crosslinking agent can be appropriately added to the conductive elastic layer as needed. In the present invention, the conductive elastic layer has a relational expression (I) 0.01 ≦ ST / D ≦ 2.0 (I) [where S is the compression set (%) and T is the thickness] (Mm),
D indicates Asker C hardness (°). ] Must be satisfied. If the S / T / D is less than 0.01, the contact of the developer carrier with the image forming body becomes insufficient, so that image unevenness occurs. Further, since the stress with the contact member such as the image forming body becomes large, when the image forming apparatus is used by being attached to the image forming apparatus, the developer carrying member or the contact member is easily damaged or the like, and an image defect is caused. Cause. On the other hand, if the S / T / D exceeds 2.0, a contact mark is likely to be formed on the developer carrying member when used in an image forming apparatus, which causes an image defect. In the present invention, it is preferable that 0.02 ≦ ST / D ≦ 1.5,
More preferably, 0.025 ≦ ST / D ≦ 1.0. That is, for example, when T = 3 mm and D = 65 °, 0.43
% ≦ S ≦ 32.5%, preferably 0.54% ≦ S
≦ 21.7% is more preferred. Also, T = 4 mm, D = 5
When the angle is 5 °, it is preferable that 0.28% ≦ S ≦ 20.6%, and it is more preferable that 0.34% ≦ S ≦ 13.8%.

In the present invention, if the Asker C hardness of the conductive elastic layer is too high, the developer carrier becomes hard, the contact area with the photoreceptor or the like becomes small, and good image formation may not be performed. Further, the developer is damaged, and the developer adheres to the photoreceptor or the layered blade, and the image is likely to be defective. If the hardness is too low, the compression set becomes large, and if the developer carrier is deformed or eccentric for some reason, image unevenness occurs and poor adhesion to the resin coating layer occurs. It will be easier.
For these reasons, the preferred Asker C hardness is 30 to 8
The range is 0 °, and the range of 40 to 70 ° is particularly preferable. In the present invention, the thickness of the conductive elastic layer is 1 to 5 mm.
Is preferable, and 2 to 4 mm is particularly preferable. The surface roughness of the conductive elastic layer is preferably 15 μmRz or less, particularly preferably 1 to 10 μmRz in terms of JIS 10-point average roughness. When the average roughness exceeds 15 μmRz,
Even when the wearable layer is formed, the layer thickness of the developer layer and the uniformity of charging may be impaired, which may cause an image defect.

In the developer carrying member of the present invention, it is possible to control the chargeability and adhesion of the developer, to reduce the frictional force between the photosensitive member and the layered blade, and to prevent the photosensitive member from being contaminated by the elastic member. Therefore, it is preferable to provide a resin coating layer on the surface of the conductive elastic substrate, that is, on the surface of the conductive elastic layer. The thickness of this resin coating layer is 1 to 1
It is preferable to be in the range of 00 μm. If the thickness of the coating layer is less than 1 μm, the coating film is not sufficiently formed, and the coating film may be lost by repeated printing by the image forming apparatus. If the thickness exceeds 100 μm, the developer carrier becomes hard, which may damage the developer and cause the developer to adhere to the image forming body or the layered blade, which may cause an image defect. For these reasons, the preferred thickness of the resin coating layer is in the range of 5 to 30 μm.

When a resin coating layer is provided on the developer carrying member of the present invention, the preferable resistance value of the coating layer is 10 ³ to 10 ³ .
In the range of 10 ¹⁶ Ω · cm, especially 10 ⁶ to 10 ¹³ Ω · cm.
The range of cm is preferred. Further, the resistance of the developer carrying member is preferably 10 ² to 10 ¹² Ω, and particularly preferably 10 ⁴ to ¹⁰ 10 Ω.
Ω is preferred. Further, the surface roughness of the developer carrier having the resin coating layer formed thereon is 10 μmR in terms of JIS 10-point average roughness.
z or less, and particularly preferably in the range of 1 to 8 μmRz. If the average roughness exceeds 10 μmRz, there is a possibility that the charge amount of the developer becomes small, or an oppositely charged developer is generated to cause image fog. On the other hand, if Rz is too small, the amount of developer carried is reduced, and the image density may be reduced. As the resin constituting the resin coating layer, a crosslinkable resin is suitable, and among them, a solvent (a good solvent such as acetone)
The insoluble portion is preferably 70% by weight or more, and if the insoluble portion is less than 70% by weight,
A pressure contact mark is formed on a member that is in contact with the developer carrier, such as an image forming body or a stratified blade, and as a result, a problem such as a black horizontal line may occur in an image. In particular, those having a solvent insoluble portion of 80% by weight or more are preferable. The crosslinkable resin refers to a resin that is self-crosslinked by heat, a catalyst, air (oxygen), moisture (water), an electron beam, or the like, or a resin that is crosslinked by a reaction with a crosslinking agent or another crosslinkable resin.

Examples of such a crosslinkable resin include a hydroxyl group, a carboxyl group, an acid anhydride group, an amino group, an imino group, an isocyanate group, a methylol group, an alkoxymethyl group, an aldehyde group, a mercapto group, an epoxy group, and an epoxy group. Fluororesins having reactive groups such as saturated groups, polyamide resins, acrylic urethane resins, alkyd resins, phenolic resins, melamine resins, silicone resins, urethane resins, polyester resins, polyvinyl acetal resins, epoxy resins, polyether resins, amino resins, acrylic resin,
Examples thereof include urea resins and the like and mixtures thereof.
Among them, fluorine resin, polyamide resin, acrylic urethane resin, alkyd resin, phenol resin, melamine resin, silicone resin, urethane resin, polyester resin, polyvinyl acetal resin, epoxy resin, and mixtures thereof are preferable, and alkyd resin is particularly preferable. , Phenolic resins, melamine resins and mixtures thereof are preferred from the viewpoints of the charging ability of the developer, the non-staining property to the developer, the reduction of the frictional force with other members, the non-staining property to the image forming body, and the like.

A catalyst, if necessary, may be added to the crosslinkable resin.
A crosslinking agent is used. Examples of the catalyst include radical catalysts such as peroxides and azo compounds, acid catalysts, and basic catalysts. The crosslinking agent has one molecule of a reactive group such as a hydroxyl group, a carboxyl group, an acid anhydride group, an amino group, an imino group, an isocyanate group, a methylol group, an alkoxymethyl group, an aldehyde group, a mercapto group, an epoxy group, and an unsaturated group. A compound having a molecular weight of 1000 or less having two or more
Preferably a compound having a molecular weight of 500 or less, for example,
Examples thereof include a polyol compound, a polyisocyanate compound, a polyaldehyde compound, a polyamine compound, and a polyepoxy compound. The cross-linkable resin may be used, if desired, with a charge control agent, a lubricant, a conductive agent, other resins, etc. for the purpose of further improving the chargeability of the developer, reducing the frictional force with other members, and imparting conductivity. And various additives can be contained. The method for forming the resin coating layer on the developer carrier of the present invention is not particularly limited, but usually, a coating solution obtained by dissolving or dispersing a crosslinkable resin, a crosslinker and various additives is dipped by a dipping method, After coating on the conductive elastic layer by a coater method, a doctor blade method, a spray method, or the like, it is dried at room temperature or at a temperature of about 50 to 170 ° C., and crosslinked and cured.

Examples of the solvent used for preparing the coating solution include alcohol solvents such as methanol, ethanol, isopropanol and butanol; ketone solvents such as acetone, methyl ethyl ketone and cyclohexanone;
Aromatic hydrocarbon solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as hexane, alicyclic hydrocarbon solvents such as cyclohexane, ester solvents such as ethyl acetate, ether solvents such as isopropyl ether and tetrahydrofuran And amide solvents such as dimethylformamide, halogenated hydrocarbon solvents such as chloroform and cycloethane, etc., and mixed solvents thereof.

The present invention also provides an image forming apparatus equipped with the above-mentioned developer carrier. There is no particular limitation on the type of the image forming apparatus of the present invention. For example, (1) a developer carrying member carrying a developer is brought into contact with an image forming body (photoreceptor) holding an electrostatic latent image, and Is applied to the latent image of the image forming body to form an image. (2) An image forming body made of paper sheets is provided with a developer carried on a developer carrying body in the form of a hole. (3) a method of forming an image by directly flying through a control electrode, and (3) a method of forming a thin film on a surface of a sleeve-like developer carrier provided in a non-contact state close to an image forming body (photoconductor). A non-magnetic developer having a layer formed thereon may be carried thereon, and the non-magnetic developer may be caused to fly onto a photoreceptor to perform development to form an image. As an example of the image forming apparatus of the present invention, the apparatus of the pressure developing system shown in FIG.

[0018]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Example 1 Polyisoprene polyol having a molecular weight of 2500 (OH value of 4
7.1) 2.85 parts by weight of acetylene black was blended with 100 parts by weight and mixed using a mixer to prepare a polyol composition. After defoaming the polyol composition by stirring under reduced pressure, 13.33 parts by weight of crude MDI (crude meta-xylylene diisocyanate) (NCO weight%: 31.7) was added, and the mixture was stirred for 2 minutes and dibutyltin dilaurate was added. 0.00
One part by weight was added and stirred for 3 minutes. Next, this is cast into a mold in which a metal shaft is arranged and heated to 90 ° C. in advance,
After curing at 90 ° C. for 12 hours, a conductive elastic layer was formed on the outer periphery of the metal shaft to obtain a roller. The surface of the obtained roller was polished, and the surface was JIS 10-point average roughness 8 μm Rz
The thickness of the conductive elastic layer was adjusted to about 3 mm. Asker C hardness of the conductive elastic layer in the above roller is 65 °
Met.

Next, 15 parts by weight of an oil-free alkyd resin and 5% by weight of a melamine resin are dissolved in toluene,
Further, the roller is immersed in a coating liquid prepared by adding and dispersing 10 parts by weight of carbon black to 100 parts by weight of the resin component and pulled up, and heated at 100 ° C. for 5 hours to form a crosslinked and cured resin. A roller having a coating layer was prepared.
This roller is set against the developing unit of the image forming apparatus shown in FIG. 2 by pressing the layering blade 8 at a linear pressure of 80 g / cm ² to set the roller as the developing roller 1. Left in the environment for 3 days. Thereafter, this developing unit was mounted on the image forming apparatus shown in FIG. 2, and an image was formed.

This roller was evaluated as follows. Table 1 shows the results. (1) Roller Resistance A roller was pressed against both ends of a copper plate with a load of 500 g applied thereto, and measured by applying a voltage of 100 V using a resistivity meter R8340A (manufactured by Advantest). (2) Roller hardness For a sheet-like sample prepared under the same conditions as each roller, using an Asker C hardness meter (manufactured by Kobunshi Keiki Co., Ltd.)
It was measured under a load of 1 kg. (3) Compression set A sheet-like sample produced under the same conditions as each roller was measured according to JIS-K6301. (4) Image evaluation Using a developing unit left for 3 days in an environment of a temperature of 30 ° C. and a relative humidity of 85%, and using a non-magnetic one-component toner having an average particle diameter of 7 μm, rotating at a peripheral speed of a linear speed of 110 mm / sec. While reversal development, an image of a black solid image and a halftone image was formed. Thereafter, continuous images were output on up to 5000 sheets, and changes in the rollers were observed. However, for rollers that have a nip line at the beginning of printing,
Only the initial image was evaluated.

Example 2 A roller was produced in the same manner as in Example 1 except that the thickness of the conductive elastic layer was changed to 1 mm, and the same evaluation was performed. Table 1 shows the results. Example 3 The components below were stirred and mixed, poured into a mold heated to 110 ° C., and cured for 2 hours to form a conductive elastic layer on the outer periphery of a metal shaft. Component of conductive elastic layer Polyether polyol (molecular weight 5000, OH value 33) 100 parts by weight 1,4-butanediol 2.0 parts by weight Silicone surfactant 1.5 parts by weight Nickel acetylacetonate 0.5 parts by weight Dibutyl Tindilaurate 0.01 parts by weight Acetylene black 2.0 parts by weight Urethane-modified MD1 (NCO weight%: 23) 20 parts by weight The molded product is polished in the same manner as in Example 1 to form a roller having a thickness of 1 mm, and further resin A coating layer was formed. The same evaluation was performed using this roller as a developing roller. Table 1 shows the results.

Example 4 A roller having a conductive elastic layer having a thickness of 3 mm was prepared in the same manner as in Example 3 except that 1,4-butanediol was not used as a component of the elastic layer. The same evaluation was performed. Table 1 shows the results. Example 5 A roller was produced in the same manner as in Example 4 except that the thickness of the conductive elastic layer was changed to 1 mm, and the same evaluation was performed. Table 1 shows the results. Comparative Example 1 A roller was produced in the same manner as in Example 3 except that the thickness of the conductive elastic layer was changed to 4 mm, and the same evaluation was performed. Table 1 shows the results.

[0023]

[Table 1]

[0024]

The developer carrier of the present invention comprises a conductive elastic substrate provided with a resin coating layer on the surface thereof, and has excellent adhesion between the conductive elastic substrate and the resin coating layer. Along with
Cracking of the resin coating layer during long-term use is prevented,
It has excellent durability and is suitably used as a developer carrier of various image forming apparatuses.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a developer carrying member of the present invention.

FIG. 2 is a schematic diagram illustrating an example of an image forming apparatus using a pressure development method.

[Explanation of symbols]

 1: developer carrier (developing roller) 2: shaft 3: conductive elastic layer 4: coating layer 5: roller for applying a developer 6: image forming body (photoreceptor) 7: developer 8: layered blade 9: transfer Unit 10: Cleaning unit 11: Cleaning blade

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Ryuta Tanaka 440-1-542, Kamiyabecho, Totsuka-ku, Yokohama-shi, Kanagawa F-term (reference) 2H077 AD02 AD06 AD13 AD17 AD23 EA14 EA15 EA16 FA01 FA22 FA25 3J103 AA02 AA14 AA21 AA51 BA34 FA03 FA09 FA12 FA14 GA02 GA57 GA58 GA66 GA74 HA03 HA04 HA12 HA20 HA53 HA54

Claims (7)

[Claims] An image forming apparatus comprising a conductive elastic layer, a developer carried on the surface thereof to form a thin film thereof, and a developer supplied to the surface of the image forming body in contact with or in proximity to the image forming body. ,
In the developer carrying member for forming a visible image, the conductive elastic layer is formed by a relational expression (I) 0.01 ≦ STT / D ≦ 2.0 (I) [where S is a compression set ( %), T is the wall thickness (mm),
D indicates Asker C hardness (°). ], A developer carrier. 2. The ST · D / D value in relational expression (I) is:
2. The developer carrier according to claim 1, wherein the ratio is 0.02 to 1.5. 3. The S · T / D value in relational expression (I) is:
The developer carrier according to claim 1, wherein the value is 0.025 to 1.0. 4. The conductive elastic layer has an Asker C hardness of 30 or more.
The developer carrier according to claim 1, wherein the developer carrier is at an angle of 80 °. 5. The conductive elastic layer is formed of at least one selected from nitrile rubber, urethane rubber, epichlorohydrin rubber, ethylene propylene rubber, ethylene propylene diene rubber and silicone rubber. 5. The developer carrier according to any one of 4. 6. The conductive elastic layer further has a thickness of 1 to
2. A resin coating layer having a thickness of 100 [mu] m.
5. The developer carrier according to any one of items 1 to 4. 7. A developer that forms a visible image by carrying a developer on the surface to form a thin film thereof and supplying the developer to the surface of the image forming body in contact with or close to the image forming body. 7. An image forming apparatus comprising a carrier, wherein the developer carrier according to claim 1 is used as the developer carrier.