JPS6070455A - Production of developer carrying body - Google Patents

Abstract

PURPOSE:To enable easy formation of a developer carrying body having a dielectric layer with which the layer thickness necessary for obtaining a desired edge effect is thoroughly assured by forming a dielectric material on a conductive base then beating the dielectric material to cure the same. CONSTITUTION:A dielectric layer 4 is deposited on a cylindrical conductive base 1 and thereafter an electrode layer 2 on which electrode particles 2a are held afloat is laminated thereon. More specifically, the outside circumferential surface of the base 1 is defatted, then a dielectric layer (about 0.5mm. is deposited by an electrostatic painting method uniformly over approximately the entire outside circumferential surface thereof. Dielectric powder 4' consisting of an electrified epoxy resin, etc. is sprayed to the base 1 facing a painting gun 10 while the gun is moved back and forth at a prescribed speed along a shaft 12. Since the surface of the base 1 is kept heated to about 180 deg. which is the melting temp. of the sprayed powder 4', the powder 4' sticking to the base melts quickly. The coated film which is deposited on the base is surely thermally cured when the dielectric coated film is obtd. to a desired film thickness by the electrostatic painting. The dielectric film 4' which is approximately uniform in both circumferential and longitudinal axial directions is easily formed without sagging of the coated film by gravity.

Description

DETAILED DESCRIPTION OF THE INVENTION LLL The present invention relates to a method for manufacturing a developer carrier, and more particularly, to a method for manufacturing a developer carrier suitable for a developing device using -component high resistance magnetic toner. .

Mistake IL In an electrostatic recording device such as an electrophotographic copying machine, facsimile, or printer, the development characteristics required of the developing device are different depending on whether the document is a line image or a solid image. FIG. 1 is a graph showing the preferable development characteristics, with the horizontal axis representing original image density and the vertical axis representing copy image density.

In the figure, the solid line A indicates the development characteristics required for the edge image, and the broken line B
indicates the development characteristics required for line images. According to this. In the case of a line image (dashed line B), a solid image (solid line A) is better than a solid image (solid line A).
) The rising slope is steeper than in the case of ). The reason for this is that if the original is a line image, the clarity of the image will be poor if the original image density is low, so it is necessary to compensate for this by increasing the density of the copy image, but if the original is a solid image, the original image density will be poor. This is because if a copy image density corresponding to the image density is obtained, the image will be sufficiently clear.

By the way, the so-called edge effect has been conventionally used to increase the density of the copied image of this line image.

That is, the strength of the electric field at the edges of the electrostatic latent image is stronger than the strength of the electric field at the center of the image, resulting in a larger amount of toner adhering to the edges of the image, resulting in an edge effect. Therefore, in the case of a line image with a small image area, most of the latent image forming area corresponds to the edge and is subject to the edge effect, resulting in a high value of the density of the copied image.

However, when using a two-component developer containing toner and carrier as a developer, a sufficient effect can be obtained for this edge effect, but when using a single-component toner that does not contain a carrier. had the disadvantage that an effective edge effect could not be obtained.

Therefore, the applicant of the present application has proposed a developing device equipped with a developer carrier having a unique configuration that makes it possible to obtain the above-mentioned suitable development characteristics even when using a -component type developer (
(Japanese Patent Application No. 185726/1982). As shown in FIG. 2, the developer carrier according to this proposal has a large number of hemispherical minute electrode particles 2a made of a conductive material on the outer peripheral surface of a cylindrical conductive support 1 in the circumferential direction. and electrode layers 2 uniformly scattered in the width direction, and these individual electrode particles 2a are mutually insulated and held in an electrically floating state. Note that when a magnetic developer is used, a magnet roller (not shown) is disposed inside the support 1 3 to supply magnetic force to support the developer.

By using the developer carrier as described above, the edge effect described above is produced as described below.

3(a) and 3(b) schematically show a photoreceptor 31 as an electrostatic latent image carrier and a developer carrier 32 disposed slightly apart from the photoreceptor 31. FIG. The photoreceptor 31 has a photosensitive layer 31b formed on a conductive substrate 31a, and the developer carrier 32 has the same structure as the developer carrier shown in FIG. The same reference numerals are given. Further, between the photoreceptor 31 and the developer carrier 32, for example, negatively charged toner as a developer is located on the surface of the electrode layer 2 of the carrier 32. It is omitted for the sake of explanation. Third (
The electrostatic latent image L1 of the line image and the electrostatic latent image L1 of the line image are formed on the photosensitive layer 31b of each photoreceptor 31 in FIG. A latent image L2 of a solid image is formed.

In each figure, the toner (
(not shown) are each latent image L+ of the photosensitive layer 31b.

By electrostatically adhering to L2, each latent image L
+, L2 is visualized. In this case, the amount of toner that adheres to the latent image depends on the strength of the electric field formed near the surface of the photosensitive layer 31b. becomes darker. First, if the electrostatic latent image is a line image as shown in FIG. It does not go toward the conductive support 1, but toward the background portion of the photosensitive layer 31b (the portion where the latent image L1 is not formed) as shown in the figure. This is the electrode particle 2
This is because the dielectric thickness from the latent image L1 to the background portion becomes smaller by providing the distance a, and the number of electric lines of force formed along a path having a relatively small dielectric thickness increases. Therefore, the strength of the electric field formed near the surface of the latent image L1 increases, and as a result, the amount of toner adhering to the latent image L1 increases significantly compared to the case where the electrode particles 2a are not provided, and the visible image becomes smaller. Concentration increases.

On the other hand, when the latent image L2 is a solid image as shown in FIG. Head to 1. This is because, even if the electrode particles 2a are provided, the dielectric thickness is smaller Δ- from the central region of the latent image L2 to the conductive support 1 than to the background portion. Therefore, for a solid image, depending on the presence or absence of the electrode particles 2a, the strength of the electric field near the surface in the central area of the latent image L2 is large (it is not affected, and the density of the visible image in this area may be increased). No. Based on this development effect, the suitable development characteristics shown in FIG. 1 are exhibited.

As is clear from the above, in order to selectively increase the number of electric lines of force at the edge of the latent image, the dielectric thickness in the path from the latent image to the support 1, which becomes the counter electrode, must be increased. In other words, it is necessary to ensure that the dielectric thickness is greater than or equal to the dielectric thickness on the path to the background.In this case, as shown in FIG. Forming the dielectric ff4 made of a dielectric material separately between the electrode particles 2a is convenient not only for ensuring the dielectric thickness but also for controlling the electrode thickness t2a of the electrode particles 2a, which will be described later. , the necessary layer thickness to of the dielectric layer 4 to be formed is expressed as tD = η × ε, where ε is the dielectric constant of the dielectric material used and η is the effective dielectric thickness.

For example, a thermosetting epoxy resin is suitable as the dielectric material, but in this case, the dielectric constant ε is 4 and the effective dielectric thickness η is Q, 1111111, so the required dielectric layer thickness to is tp = 0. .1 x 4 = 0.4 (mm). In order to secure the required thickness to of 0.4 rthm, it is necessary to deposit a dielectric layer of, for example, about 0.5 mm on the support, taking into account processing allowance for smoothing the surface.

However, it is extremely difficult to deposit a dielectric material such as an epoxy resin on a dielectric support as thickly and approximately uniformly as the thickness is about 0.5111. - As an example, when an epoxy resin was coated on the support 1 by an electrostatic coating method after heating in a heating furnace with a built-in core metal for heat insulation, the thickness of the obtained dielectric layer was 0.3~ It was about 0.4 mm.

Purpose The present invention has been made in view of the above points, and it is an object of the present invention to easily produce a developer carrier having a dielectric layer having a sufficient layer thickness necessary to obtain a desired edge effect. The purpose is to provide a manufacturing method.

Configuration Hereinafter, the configuration of the present invention will be explained in detail based on specific examples. The developer carrier to be manufactured by the manufacturing method of this example is made by forming a dielectric layer 4 on a conductive support 1 as shown in FIG. 2 is a developer carrier configured and constructed by laminating layers.

First, as shown in FIG. 5, a cylindrical conductive support 1 is prepared. In this case, if a magnetic developer is used as the developer and is applied to a developing device of a type in which the developer is supported by magnetic force, the conductive support 1 is made of a thin non-magnetic material such as stainless steel.

Next, after degreasing the outer peripheral surface of the support 1, a dielectric layer is uniformly applied over substantially the entire outer peripheral surface by an electrostatic coating method. Here, an example of a manufacturing apparatus used in this dielectric layer deposition step will be described with reference to FIG. 5. A cylindrical sheathed heater 6 having a spiral heater 6a attached to its inner peripheral surface is supported horizontally and rotatably on, for example, a side wall H of a painting booth. A pulley 7a is fixed to one end of the rotating shaft 6b of the sheathed heater 6, and a belt 7b is suspended from the pulley 7a, and the rotation is transmitted to a sheathed heater drive motor (not shown) with an appropriate speed change. Rotating shaft 6
b and the sheathed heater 6 are rotated together at a predetermined speed. Further, a slip ring 8 is provided at the end of the pulley 7 as a contact point for energizing the heater 6a, so that the heater 6a can be energized without interruption even while the sheathed heater 6 is rotating.

The slip ring 8 has a built-in temperature control means (not shown) and is connected to a power supply device 9 equipped with a temperature setting knob 9a and an on/off switch 9b. ) is configured such that a current controlled by a temperature control means is applied to heat the support 1 to a desired temperature, for example, 180°C.

On the other hand, a coating gun 10 that applies dielectric powder 4- to the support 1 by electrostatic coating is held on a holding table 11 that is movably provided in parallel to the longitudinal axis of the sheathed heater 6. . The holding table 11 is supported by two shafts 12 inserted through its carriage portion 11a, and one of the two shafts 12 is a support shaft 12a with a smooth surface and is slidable on the carriage portion 11a. One of the shafts has a thread formed on its surface and is inserted into the carriage part 11a in a screwed state by a drive shaft 12b that reciprocates the holding base 11. The two shafts 12 are each rotatably supported at both ends by a pair of blocks 13a, 13b. And block 13b of drive shaft 12b
The tip of the end supported by is connected to a rotary drive motor 14 whose rotation direction can be freely switched. Therefore, by rotating the drive motor 14 clockwise, for example, the holding base 11 moves toward the block 13a at a speed changed by the screw, and when the rotation direction of the drive motor 14 is switched counterclockwise, the holding base 11 moves in the opposite direction. move at the same speed.

Further, the coating gun 10 is connected to a high pressure generator 15 and a powder atomizing device 16 for atomizing the dielectric powder 4 into compressed air, thereby forming a normal electrostatic coating device. Note that one end of the high pressure generator 15 and the outer cylinder of the sheathed heater 6 described above are each grounded.

The steps carried out by the dielectric layer deposition apparatus constructed as described above will now be described. First, after extrapolating the support 1 to the sheathed heater 6, the sheathed heater 6 is connected to the drive motor (
(not shown) at a predetermined speed via a belt 7b, the temperature setting knob 9a of the power supply device 9 is set to a desired temperature, for example, 180° C., and the switch 9b is turned on. After molding and confirming that the support 1 has been heated to 180° C., electrostatic coating is started. The electrostatic coating method in this example is
It is based on the normal air atomization electrostatic coating method, and by applying a negative high voltage to, for example, the vicinity of the nozzle 10a of the coating gun 10 by the high voltage generator 15, the voltage is applied to the grounded sheathed heater 6. For example, the conductive support 1 serves as a positive counter electrode, and an electrostatic field is formed between the two electrodes, and the dielectric powder 4- sprayed from the coating gun 10 is negatively charged near the nozzle 10a, and the positive support 1 It is attracted to the surface and efficiently adheres to the surface, forming a coating film. do. Formation of a dielectric coating film by such an electrostatic coating method is repeatedly carried out for a predetermined period of time over substantially the entire circumferential surface of the support, and a desired M electrical coating film with a thickness of about 0.5 mm is formed. is obtained. That is, drive motor 1
The dielectric powder 4-, which is made of epoxy resin in this example, is charged while the coating gun 10 is moved back and forth along the shaft 12 at a predetermined speed together with the holding table 11.
is sprayed onto the opposing support 1. Sprayed powder 4'
is attracted to the surface of the support 1 by electrostatic force, but
Since the surface of the support 1 is heated to around its melting temperature of 180° C., the adhered powder 4' melts quickly.

During this time, the support 1 is rotated at a predetermined speed and supported horizontally, so that the powder 4 is uniformly and repeatedly melted and adhered to substantially the entire circumferential surface of the support 1, and the film thickness is, for example, about 0.5.
A thick, uniform coating film (n+n+) is efficiently deposited.

When a dielectric coating film of the desired thickness is obtained by electrostatic coating, the electrostatic coating is stopped, but the heating and rotation of the sheathed heater 6 is continued for an appropriate period of time, as shown in FIG. To reliably heat cure a deposited coating film. As a result, a dielectric coating film 4' having a substantially uniform film thickness ta' both in the circumferential direction and in the longitudinal direction can be easily formed without the coating film sagging along the gravity (Fig. 6(b)). reference).

In addition, in the process from application of the dielectric coating film to heat curing described above, a sheathed heater 6 is used as shown in FIG. 6(b).
If the outer diameter d1 of the sheathed heater 6 is made smaller than the inner diameter d2 of the cylindrical support 1 to the extent that the sheathed heater 6 and the cylindrical support 1 do not move together, the sheathed heater 6 and the support 1 will come into line contact. As the sheathed heater 6 rotates, this line contact portion moves on the inner peripheral surface of the support 1. Therefore,
It becomes possible to heat the support 1 more evenly over the entire circumference and to uniformly melt and adhere the dielectric powder 4'. Furthermore, the work of attaching and detaching the support body 1 to and from the sheathed heater 6 becomes easy.

The surface of the deposited dielectric coating film 4- usually has a large number of irregularities, which, if left as is, will be inconvenient in terms of countermeasures against the edge effect described above and electrode thickness control described later. Therefore, a first outer diameter process is performed using a machine tool such as a lathe to smooth the surface and form a dielectric layer having a uniform layer thickness of 0.4 mm as desired. In this example, as shown in FIG. 7, a centering jig 5 having a tapered portion 5a formed in the center is press-fitted into both ends of the workpiece W, and a centering jig 5 as shown in FIG. While supporting both ends of the support body 1 with a support tool of a lathe via the jig 5, a cutting tool B is pressed against this to perform turning processing. By fitting and supporting the tip of M, the machining axis C' in the first outer diameter machining step and the central axis C of the support body 1 are approximately aligned, and the layer thickness t4 is uniformly 0.4 mm. It is possible to precisely process the dielectric layer 4. Note that it is also possible to perform this first outer diameter processing step using another cylindrical grinder, for example.

After finishing the dielectric layer 4 by outer diameter processing, the support 1 is
The surface of the dielectric layer 4 is cleaned with the extraction jig 5 attached, and then, as shown in FIG. 9, a dielectric, room-temperature curing adhesive such as acrylic urethane is applied to the surface of the dielectric layer 4 using, for example, a pressure-feeding air sprayer 17. Apply 2b evenly. As a result, the adhesive 11!2b as shown in FIG. 10 is deposited, but its film thickness t2- is the same as that of a large number of particles with a particle diameter of 74 to 104 pm, which will be sprayed in the next layer process (see FIG. 11). A suitable value is about 4 to 511II+, where the electrode particles 2a are easily held in a state in which they are uniformly in contact with the surface of the dielectric layer 4. still,
In this process as well, if the workpiece W is supported horizontally while being rotated at an appropriate speed as in the case of forming the dielectric film, and the above-mentioned adhesive is repeatedly applied along the workpiece W, a uniform coating can be obtained. The adhesive film 2b having a certain thickness can be easily formed.

After applying the adhesive, and before it hardens, the electrode particles 2a are coated with the adhesive l! as shown in FIG. 2bσ, the electrode particles 2a are spread evenly over the dielectric layer 4 as shown in FIG.
It is applied almost uniformly while in contact with the surface. For scattering these particles, for example, as shown in FIG.
In this example, a large amount of copper particles having a particle size of about 74 to 104 μm are stored as electrode particles 2a in a tray 18 equipped with a The particles 2a are dropped little by little from the spraying port 18a by moving repeatedly at an appropriate speed and tilted appropriately, and are sprinkled onto the adhesive film 2b to be uniformly distributed. In this case, each electrode particle 2a used here is coated with a dielectric material such as acrylic lacquer in advance, and therefore the electrode particles 2a are randomly attached to the adhesive 1!2b by gravity.
Even if the individual particles 2a are deposited inside, they are reliably maintained in an insulated state (floating state) with respect to the surroundings. Furthermore, since the thickness of the adhesive film 2b is as thin as about 4 to 5 μm, buoyancy that can suspend the dispersed copper particles 2a with particle diameters of 74 to 104 pffI is not generated, and each particle 2a naturally floats on the surface of the dielectric layer 4. It will be in a state where it has sunk to the top. Therefore, as shown in FIG. 12, the bottom surface of each electrode particle 2a can be easily and reliably aligned with the surface of the dielectric layer 4 simply by allowing the individual electrode particles 2a to fall naturally.

Note that in this example, copper particles were used as the electrode particles 2a, but
The present invention is not limited to this, and particles of other conductive materials such as brass, phosphor bronze, or stainless steel can also be used.

Next, after drying and curing the adhesive 2b almost completely,
As shown in the figure, the dielectric adhesive is again sprayed onto the electrode particles 2a and the hardened adhesive 2b which have been sprayed in the same manner as the previous time. In this case, if an adhesive of the same substance as the previous one is used, the two will surely adhere to each other and the electrode particles 2a will be attached to the dielectric layer 4.
This is advantageous in terms of durability because it can be more firmly fixed when in contact with a surface. However, as long as the particles 2a can be bonded to each other and the particles 2a can be reliably fixed, a combination of dielectric adhesives made of different substances is also possible. By applying the adhesive twice in between the drying process in this way, each electrode particle 2a can be firmly fixed in a state of sinking to the surface of the dielectric layer 4 without floating, and the bottom surface of each particle 2a can be firmly fixed. It is possible to easily achieve the precondition for keeping the electrode thickness within a predetermined tolerance range by locating the electrodes at approximately the same level.

When the second adhesive application is completed and it is completely cured, a second outer diameter machining is performed using a lathe, as shown in FIG. 14, and the surface of the workpiece W is polished as shown in FIG. The electrode layer 2 is formed by smoothing the surface and cutting the electrode particles 2a until they become approximately hemispherical so that a portion thereof is exposed on the surface. In this case, since the centering jig 5 used when performing the first outer diameter machining on the dielectric layer 4 is still attached to both ends of the workpiece W, the fitting portion 5a of this centering jig 5 is still attached. If the tip of the mandrel M of the lathe is fitted and supported as in the previous case, the machining axis during the first outer diameter machining and the machining axis during the second outer diameter machining will substantially coincide.

Therefore, the layer thickness t2 of the formed electrode H2 is approximately uniform over the entire circumferential surface, and the electrode thickness can be easily kept within a predetermined tolerance range. That is, in order to obtain the desired edge effect, the exposed area of the electrode particles 2a should account for 45% or more of the total electrode layer surface area, and in order to prevent the electrode particles from detaching, the removal of the particle volume should be suppressed to less than half. To satisfy these conditions, for example, when using particles with a particle size of 74 to 104 μm, the thickness of the electrode particles should be 52 to 627 II11.
I know that it is best to keep it within the range of . By the way, in this example, the electrode particles 2a are attached to the dielectric layer 4 as shown in FIG.
Since it is attached in contact with the surface, the thickness t2a of the electrode particle 2a after the second outer diameter processing is equal to the layer thickness t2 of the electrode layer 2. Therefore, the thickness t2a of the electrode particle 2a
In order to keep the electrode layer thickness [2] within the above-mentioned allowable range, turning may be performed so that the electrode layer thickness [2] falls within the same range of 52 to 62 J-. The processing condition of keeping the electrode layer thickness [2] within the above-mentioned allowable range of width 10 μm can be easily achieved by the method of forming the electrode layer 2 using the centering jig 5 of this example described above.

After supporting the workpiece W via the centering jig 5, turning is performed using a normal lathe, as shown in FIG.
An electrode layer 2 having a thickness of 52 to 62P is formed. Incidentally, this second outer diameter machining step can also be carried out by other means such as a cylindrical grinder. After machining the outer diameter of the electrode layer 2 to predetermined dimensions with high precision, clean the dirt such as cutting oil and remove the centering jig 5 from both ends of the workpiece W, as shown in FIG. 15. The developer carrier 19 as a final product is completed.

In the above embodiments, the process of applying the adhesive is divided into two processes, but it may be divided into three or more processes if necessary. It is also possible to form the dielectric layer 4 and the adhesive 2b from the same or the same type of dielectric material. Further, if the centering jig 5 becomes an obstacle in an intermediate process, it can be attached and detached as appropriate, and there is no risk that the machining axis will shift beyond the allowable limit.

As described in detail above, according to the present invention, a dielectric coating film having a desired thickness can be easily and efficiently deposited. Therefore, a developer carrier that can reliably exhibit the desired edge effect and stably exhibit suitable development characteristics as shown in FIG. 1 can be manufactured at a low cost. It should be noted that the present invention is not limited to the specific embodiments described above, and it goes without saying that various modifications can be made within the technical scope of the present invention.

For example, when applying adhesive, it is possible to use a dip molding method, etc., and the process of applying electrode particles can be performed by placing a workpiece to which the adhesive has been applied on which the electrode particles are laid. It can also be carried out by rolling on a bed of particles.

[Brief explanation of drawings]

FIG. 1 is a graph showing suitable development characteristics, FIG. 2 is a schematic cross-sectional view showing a conventional developer carrier, and FIGS. 3(a) and 3(b) are line images and FIG. 4 is a schematic sectional view showing a part of a developer carrier to be manufactured by a manufacturing method as an embodiment of the present invention, and FIG. Fig. 5 is a perspective view showing an apparatus used in the process of applying dielectric coating 1I4- in one embodiment of the present invention, and Fig. 6(a) similarly shows the curing process of dielectric coating 4'. FIG. 6(b) is a schematic side sectional view showing a modified example of the support mode of the support 1, and FIG. 7 is a schematic sectional view showing the mounting process of the center height jig 5. 8 are schematic cross-sectional views showing the first outer diameter processing step, and FIG. 9 and FIG. 10 are schematic cross-sectional views showing the adhesive application step and the amount of adhesive formed. Figure 11, 12th
The figures are also schematic cross-sectional views showing the electrode particle adhesion process and the amount of electrode particle formation, FIG. 13 is a schematic cross-sectional view showing the thick adhesive coating process, and FIG. 14 is the second outer diameter processing process. FIG. 15 is a schematic cross-sectional view showing the removal process of the core height jig 5 and the completed developer carrier 19. (Explanation of symbols) 1: Conductive support 2: Electrode layer 2a: Electrode particles 4': Dielectric coating film (powder) 4: Dielectric layer 5: Core jig 6: Sheathed heater 10: Paint gun patent applicant stock Company Rico Part 1 Figure 2 Figure 0 0 Figure 3 (o) Figure 3 (b) Figure G Figure 4 Figure 6 (O) Figure W ~ Now Figure 6 (b) Figure 7 Figure 8 Figure 10 Figure 11 Figure 20 Figure 12 Figure 14 Figure 15 Figure 9 Amendment to standard procedures November 9, 1980 Director of the Japan Patent Office Kazuo Wakasugi 1, Indication of the case 1981 Patent Application No. 178
No. 286 No. 2, Title of the invention Method for manufacturing developer carrier 3
6 Relationship with the case of the person making the amendment Patent applicant address 1-3-6 Nakamagome, Ota-ku, Tokyo Name (67
4) Ricoh Co., Ltd. -4, Agent 6, Number of inventions increased by amendment None 2-11φ -+7 Contents of amendment In the column of "Detailed Description of the Invention" of the specification of the application, the following points have been added: to correct. 1. On page 17, in the first line, "4 to 5" is replaced with "3".
〜15μ」 and 2 characters are corrected. 2. On page 18, in line 5, replace “4 to 5 μm” with “
3 to 15 μm” and 2 characters are corrected. (Above) Procedural amendment dated November 16, 1980 Kazuo Wakasugi, Commissioner of the Patent Office 1, Indication of the case 1981 Patent Application No. 178
No. 286 No. 2, Title of the invention Method for manufacturing developer carrier 3
, Relationship with the case of the person making the amendment Patent applicant: 4, Agent: 6, Number of inventions increased by the amendment: None 7, Subject of the amendment: Description

Claims (1)

[Claims] 1. A dielectric layer made of a dielectric material is formed on the circumferential surface of a cylindrical conductive support, and a large number of conductive particles are maintained on the dielectric layer in an electrically insulated state from each other. In the method for manufacturing a developer carrier having laminated electrode layers, the conductive support is heated to a predetermined temperature and a dielectric material is deposited on the peripheral surface of the support by an electrostatic coating method. 1. A method for producing a developer carrier, comprising: a step of maintaining the support in a heated state to thermally harden the deposited dielectric. 2. In the above item 1, the dielectric is a thermosetting epoxy resin, and the conductive support is heated by being inserted into a sheathed heater having a built-in heater. A method for manufacturing a developer carrier. 3. In the above item 2, the developer carrier is characterized in that the sheathed heater is horizontally supported and rotatably provided, and supports the conductive support horizontally while rotating it. manufacturing method. 4. In the above item 2, the outer diameter of the sheathed heater is formed to be smaller than the inner diameter of the conductive support, and a portion of the inner circumferential surface of the support that contacts the outer circumferential surface of the sheathed heater is A method for manufacturing a developer carrier, characterized in that the developer carrier changes depending on the rotation of the developer carrier. 5. The method for producing a developer carrier according to item 1 above, wherein the coating gun in the electrostatic coating method is reciprocated in parallel to the longitudinal axis of the conductive support.