JPH10264268A - Manufacture of intermediate transfer printing belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce variation of inner periphery length of a belt, and extension which is generated when the belt is passed about and driven, or reduce belt extension with time by heat treating, with the belt extended, the fiber reinforced endless belt having an elastic layer composed of resin or rubber. SOLUTION: An endless belt is heat-treated with the belt extended. The extension rate of the endless belt at the time of heat-treating is set appropriately according to elastic layer material composed of resin or rubber, and reinforcing fiber type, state, etc. Normally, it is preferable to make distance between axes L the reference inner periphery length, and to heat treat the belt by extending specially by 0.1-5%. In this case, extension rate of the endless belt fitted to the outer periphery of a cylindrical mold after vulcanized forming is normally 0.1-0.5%. The distance between axes L is the distance between both axes 21a and 21b, when the endless belt 20 is passed around a pair of axes 21a and 21b with one axis 21b fixed and separating the other axis 21a with the force of 10 kg.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method such as a latent image holding member having an electrostatic latent image on the surface in an electrostatic recording process in an electrophotographic apparatus such as a copying machine or a printer or an electrostatic recording apparatus. A method for manufacturing an intermediate transfer belt for temporarily transferring and holding a toner image formed by supplying a developer to a body surface before transferring the toner image to a recording medium such as paper, and transferring this to the recording medium. More specifically, it is possible to reliably obtain an intermediate transfer belt having excellent dimensional accuracy by reducing the variation in the inner peripheral length of the obtained belt, and to obtain the elongation and the lapse of time during stretching and driving of the obtained belt. The present invention relates to a method for manufacturing an intermediate transfer belt capable of reducing a large elongation and its variation.

[0002]

2. Description of the Related Art Conventionally, in an electrostatic recording process in a copying machine, a printer, or the like, first, a photosensitive member (latent image holding member)
Surface is uniformly charged, an image is projected from the optical system onto the photoreceptor to eliminate the charging of the light-exposed portion, thereby forming an electrostatic latent image. Is supplied to form a toner image by electrostatic adhesion of the toner, and the toner image is transferred to a recording medium such as paper to perform printing.

In this case, even in a color printer or a color copying machine, printing is basically performed in accordance with the above-described process. In the case of color printing, magenta, yellow, cyan, and black toners are used. In order to reproduce the color tone, it is necessary to perform a process of superposing these toners at a predetermined ratio to obtain a necessary color tone, and several methods have been proposed for performing this process.

First, as in the case of monochrome printing, when the electrostatic latent image is visualized by supplying toner onto the photoreceptor, the above four colors of magenta, yellow, cyan and black are used. There is a multiple development system in which development is performed by sequentially superimposing toner to form a color toner image on a photoconductor. According to this method, it is possible to configure the apparatus relatively compact, but in this method, there is a problem that it is very difficult to control the gradation and high image quality cannot be obtained.

Second, by providing four photosensitive drums and developing the latent images of the respective drums with magenta, yellow, cyan, and black toners, a magenta toner image, a yellow toner image, and a cyan toner image are formed. And four toner images of a black toner image are formed, the photosensitive drums on which the toner images are formed are arranged in a line, and each toner image is sequentially transferred to a recording medium such as paper, and is superimposed on the recording medium. There is a tandem system for reproducing a color image. In this method, although a good image is obtained, four photosensitive drums, and a charging mechanism and a developing mechanism provided for each photosensitive drum are arranged in a line.
The device becomes larger and more expensive.

Third, a recording medium such as paper is wound around a transfer drum and rotated four times, and magenta, yellow, cyan, and black on the photoreceptor are sequentially transferred to the recording medium for each revolution to reproduce a color image. There is also a transfer drum system that performs the transfer. According to this method, a relatively high image quality can be obtained, but when the recording medium is thick paper such as a postcard, it is difficult to wind it around the transfer drum, and the type of recording medium is limited. There is.

As compared with the above-described multiple developing system, tandem system and transfer drum system, good image quality can be obtained, the apparatus is not particularly enlarged, and the type of recording medium is particularly limited. An intermediate transfer method has been proposed as a method without such a method.

That is, in the intermediate transfer system, as shown in FIG. 1, for example, a first developing device 4a for developing an electrostatic latent image on a photosensitive drum 2a with yellow, and an electrostatic latent image on a photosensitive drum 2b Developing device 4b for developing magenta with magenta
And a third developing device 4c for developing the electrostatic latent image on the photosensitive drum 2c with cyan, and a fourth developing device 4d for developing the electrostatic latent image on the photosensitive drum 2d with black. And the intermediate transfer belt 1 is driven to circulate in the direction of the arrow in FIG. By transferring, a color image is formed on the intermediate transfer belt 1, and this color image is transferred onto a recording medium 3 such as paper and printed. Therefore, since the gradation is adjusted by superimposing the four color toner images, it is possible to obtain high image quality.
Also, unlike the tandem type, there is no need to arrange the photoconductors in one row, so that the apparatus is not particularly large, and the recording medium does not need to be wound around the drum, so that the type of recording medium is not limited. is there. In the figure, 5, 5,
Reference numeral 5 denotes a drive roller for circulating the intermediate transfer belt 1; 6, a recording medium feed roller; 7, 7, a recording medium transport device; In the figure, reference numeral 9 denotes a power supply device (voltage applying means) for applying a voltage to the intermediate transfer belt 1. The power supply device 9 transfers a toner image from the photosensitive drums 2a to 2d to the intermediate transfer member 1. The polarity of the applied voltage can be reversed between the transfer of the toner image from the intermediate transfer member 1 to the recording medium 3.

As the intermediate transfer belt 1 used in the intermediate transfer system, an endless fiber-reinforced endless belt having an elastic layer formed of resin or rubber is used. It is manufactured by winding and vulcanizing the above-mentioned elastic layer formed into a reinforcing fiber and a sheet.

[0010]

However, the intermediate transfer belt manufactured by the conventional method tends to have a variation in the circumference after molding and vulcanization, and it is not always possible to stably obtain a belt having excellent dimensional accuracy. Can not. Further, there is a variation in elongation generated when the belt is stretched between the drive rollers 5, 5, 5, and the belt may not be able to rotate normally. While the process is continued, elongation occurs with time, and good operation may not be achieved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is possible to reduce the variation in the inner circumferential length of the obtained belt and to reliably obtain an intermediate transfer belt having excellent dimensional accuracy. It is an object of the present invention to provide a method of manufacturing an intermediate transfer belt that can reduce the elongation caused during stretching and driving and the elongation over time.

[0012]

Means for Solving the Problems and Embodiments of the Invention The present inventor has made intensive studies to achieve the above object, and as a result, has been made of a fiber-reinforced endless belt having an elastic layer made of resin or rubber. When manufacturing an intermediate transfer belt that is disposed between an image forming body and a recording medium and temporarily transfers and holds a toner image formed on the surface of the image forming body to its own surface, and transfers this to a recording medium. In addition, the endless belt is subjected to a heat treatment in an expanded state, so that the variation in the inner peripheral length of the obtained belt can be reduced. The present invention has been found to be capable of operating stably with little elongation, and has completed the present invention.

Accordingly, the present invention is provided between an image forming body and a recording medium, and temporarily transfers and holds the toner image formed on the surface of the image forming body to its own surface, and transfers the toner image to the recording medium. A method of manufacturing an intermediate transfer belt, comprising: heating a fiber-reinforced endless belt having an elastic layer made of resin or rubber in an expanded state. Is what you do.

Hereinafter, the present invention will be described in more detail.
In the method of manufacturing an intermediate transfer member according to the present invention, as described above, a fiber-reinforced endless belt having an elastic layer made of resin or rubber is subjected to heat treatment in an expanded state.

In this case, the resin or rubber forming the elastic layer of the endless belt is not particularly limited, and a resin such as urethane, a rubber, or a foam thereof, which is used for an ordinary intermediate transfer belt, can be used. . Specifically, nitrile rubber (NBR), chloroprene rubber (CR), isoprene rubber (IR), styrene butadiene rubber (SB
R), ethylene propylene rubber (EPDM), butyl rubber (IIR), natural rubber (NR), butadiene rubber (B
R), general rubber such as acrylic rubber (ACR), epichlorohydrin rubber (ECO) or styrene-butadiene-styrene rubber (SBS) or its water additive (SE)
BS) and the like, and foams thereof can be used, and are not particularly limited.
From the viewpoints of processability, hardness and the like, a rubber composition obtained by adding NBR, BR, or IR having low viscosity to NBR or ECO is preferably used. In this case, a preferable compounding ratio is (NBR or ECR) :( NBR + BR + I
R) = 10-90: 90-10.

Further, by adding a conductive material to these resins or rubbers, it is possible to impart conductivity to the elastic layer or adjust the conductivity of the elastic layer. In this case, the conductive material is not particularly limited, and may be lauryltrimethylammonium, styaryltrimethylammonium, octadecyltrimethylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, a perchlorate of a modified fatty acid / dimethylethylammonium salt, chlorine, or the like. Cationic surfactants such as quaternary ammonium salts such as acid salts, borohydrofluoric acid salts, sulfates, ethosulfate salts, and benzyl halide salts (verzyl bromide salts, benzyl chloride salts, etc.); aliphatic sulfonic acids, Higher alcohol sulfates, higher alcohol ethylene oxide addition sulfates,
Anionic surfactants such as higher alcohol phosphate esters; amphoteric surfactants such as various betaines; antistatic agents such as nonionic antistatic agents such as higher alcohol ethylene oxide, polyethylene glycol fatty acid esters, and polyhydric alcohol fatty acid esters Agent; LiCF ₂ SO ₂ ,
A metal salt of Group 1 of the periodic table such as NaClO ₄ , LiBF ₄ or NaCl; a metal salt of Group ₂ of the periodic table such as Ca (ClO ₄ ) ₂ ; and active hydrogen in which these antistatic agents react with isocyanate And a group having at least one group having a hydroxyl group, a carboxyl group, a primary or secondary amine group, or the like. Further, ions such as complexes of these with polyhydric alcohols (1,4-butanediol, ethylene glycol, polyethylene glycol, propylene glycol, etc.) or derivatives thereof, or complexes with ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, etc. Conductive agent; conductive carbon such as Ketjen black, acetylene black; SAF, ISAF, HAF, F
Rubber carbon such as EF, GPF, SRF, FT, MT; carbon for oxidized color ink, pyrolytic carbon, natural graphite, artificial graphite, etc .; tin oxide, titanium oxide, zinc oxide, nickel, copper, etc. Examples of metals and metal oxides include conductive polymers such as polyaniline, polypyrrole, and polyacetylene.

The amount of the conductive material to be added can be 0.01 to 50 parts by weight, preferably 0.1 to 30 parts by weight, based on 100 parts by weight of the resin or rubber component. The value can be adjusted to 10 ² to 10 ¹⁴ Ωcm. In addition, other additives such as known fillers and vulcanizing agents can be added to the elastic layer as needed in an appropriate amount.

The endless belt used in the present invention is a fiber-reinforced belt. In this case, the reinforcing fibers are not particularly limited, but include cotton, human silk, nylon, polyester, aramid, and the like. Glass, steel or other long fibers or short fibers can be kneaded into the resin or rubber that forms the elastic layer and used, or they can be formed using cotton, human silk, nylon, or other canvas. An elastic layer made of the above resin or rubber may be laminated on the canvas.
In this case, although not particularly limited, in the manufacturing method of the present invention, it is preferable to use an endless belt reinforced with canvas.

Here, the canvas can be used by laminating a plurality thereof. Further, although not particularly limited, the fiber diameter of these canvases is preferably 20 to 100 denier, particularly preferably 30 to 80 denier. Further, the canvas is preferably relatively thin, specifically, 0.01 to 0.2 mm in thickness, particularly 0.05 to 0.2 mm.
It is preferably 15 mm. In this case, if the thickness of the canvas is less than 0.01 mm, the dimensional stability due to the canvas may be reduced and the belt may be deformed such as large elongation. Flexibility may be impaired.

When laminating the canvas and the elastic layer, the surface of the canvas can be impregnated with rubber or resin if necessary, whereby the adhesion between the canvas and the elastic layer and the surface smoothness can be achieved. Performance can be improved. In this case, as the rubber or resin to be impregnated, rubber cement made of the same kind of rubber as that used for the elastic layer described above is preferably used, and the rubber cement is impregnated on the surface of the canvas in advance by coating or dipping. Can be kept.

Here, when the canvas and the elastic layer are laminated, even if the elastic layers are formed on both sides of the canvas layer, the photosensitive drums 2a to 2d (latent image holders) and the recording medium 3 are formed. The toner image may be formed on only one side on the side where the toner image is transferred or held in contact with or in close proximity. Further, the thickness of only one side of the elastic layer is not particularly limited, but is not limited to 0.1.
It is preferable to set it to about 01 to 2 mm, especially about 0.05 to 0.5 mm.

A coating layer can be formed on the surface of the endless belt, if necessary, in order to prevent adhesion and fusion of toner. The material for forming the coating layer is not particularly limited, but is a fluororesin or a fluororubber, polyamide, polyurethane, polyester, alkyd resin, melamine resin, phenol resin, epoxy resin, acrylic resin, acrylic silicone resin. And one or more resins such as acrylic urethane resin, silicone resin, amino resin, urea resin and the like.

Here, the coating layer is not particularly limited, but is preferably formed using a resin containing a fluororesin. In this case, the fluororesin is
Polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-ethylene copolymer, polychlorotrifluoroethylene, chlorotri Fluoroethylene-ethylene copolymer, polyvinylidene fluoride, polyvinyl fluoride, and the like are preferably used, so that adhesion and fusion of the toner can be more effectively prevented.

Although not particularly limited, the coating layer may contain the same conductive material as that of the elastic layer in order to impart appropriate conductivity. In this case, the amount of conductive material, in particular is suitably selected according to the restricted not desired resistance value, usually a volume resistivity from 10 ² to 10
^The amount of the conductive agent is selected so as to be ¹⁸ Ωcm, particularly 10 ⁵ to 10 ¹⁸ Ωcm, and is usually about 0.001 to 80 phr with respect to 100 parts by weight of the resin component.

Further, additives such as a thixotropy-imparting agent and a structural viscosity-imparting agent may be added to the coating layer.
These may be either inorganic or organic and include, for example, silica compounds.

When the coating layer is provided, another resin layer or rubber layer may be formed between the coating layer and the elastic layer according to the purpose.

Other materials for forming the resin layer or rubber layer include the same rubber as the above-mentioned elastic layer, chlorinated polyethylene, chlorosulfonated polyethylene, polyester resin, acrylic resin, urethane resin, polydioxolane resin. And urethane-modified acrylic resin, nylon resin, epoxy resin, styrene resin, polyvinyl acetal resin, fluororesin, fluororubber and the like.

In the other resin layer or rubber layer, the same conductive material as that of the elastic layer is used in an amount of 0.01 to 50 parts by weight, preferably 0.1 to 50 parts by weight, based on 100 parts by weight of the resin or rubber component.
About 30 parts by weight and the resistance value is 10 ² to 10 ¹⁴ Ω
cm, especially 10 ⁵ to 10 ¹⁴ Ωcm. Further, the thickness of the other resin layer or rubber layer is not particularly limited, but may be generally about 1 to 600 μm, and may be a single layer or a plurality of layers.

The endless belt used in the production method of the present invention can be obtained by a usual method, and can be easily formed by, for example, a method using a cylindrical mold. That is, when canvas is used as the reinforcing fiber, the canvas impregnated with the rubber cement is wound around the outer periphery of the cylindrical mold, and an elastic layer extruded and formed in a sheet shape thereon and, if necessary, the other resin layer or The endless belt can be obtained by winding and laminating a rubber layer, vulcanizing and curing to obtain a belt and, if necessary, forming the coating layer on the surface of the belt. In this case, when the elastic layer is formed on both surfaces of the canvas layer, first, the elastic layer is wound around the outer periphery of the cylindrical mold, then the canvas is wound, and then the elastic layer is wound thereon and vulcanized. Just do it. Also,
When kneading the reinforcing fibers into the elastic layer, kneading the reinforcing fibers uniformly into a resin composition or a rubber composition, extruding them into a sheet shape, directly winding this around the outer periphery of the cylindrical mold, and similarly. Vulcanization molding.

In the manufacturing method of the present invention, the dimensional stability is improved by performing a heat treatment in a state where the endless belt is expanded. In this case, the method of expanding the endless belt is not particularly limited and can be appropriately selected. In particular, since the endless belt can be uniformly expanded over the entire circumference, a method using an expansion / contraction drum is preferably employed. . That is, the endless belt can be wound around the outer circumference of the expansion / contraction drum whose outer peripheral length can be changed, and the endless belt can be expanded by expanding the diameter of the expansion / contraction drum at a predetermined ratio. Heating can be performed in this state. If an example of the expansion / contraction drum used in this method is shown, an expansion / contraction drum having the structure shown in FIG. 2 can be exemplified.

As shown in FIG. 2, this expanding / contracting drum has a plurality (four in the figure) of arc-shaped cross sections 11a,
A stretchable urethane layer 12 is formed on the outer circumference of the expansion / contraction cylinder 11 divided into 11b, 11c, 11d, and truncated conical expansion / compression pieces 14a, 14b are inserted into both ends of the expansion / contraction cylinder 11, respectively. Then, these scaled frames 14
a and 14b are connected by bolts 13. The inner peripheral surfaces at both ends of the expansion / contraction cylinder 11 are tapered surfaces that gradually decrease in diameter inward, and the base end of the bolt 13 is integrally connected to one of the expansion / contraction pieces 14a. A screw is formed at the other end of the bolt 13, and the other end penetrates the other expansion / compression piece 14 b and a nut 15 is screwed to the tip, thereby forming the two expansion / compression pieces 1.
4a and 14b are mutually connected. by this,
As shown by the dashed lines 14a 'and 14b' in FIG.
a, 14b move toward each other and enter the expansion / contraction cylinder 11, whereby the divided portions 11a, 11b, 11c, 11d are spread outward as indicated by the dashed line 12 '. By moving, the outer diameter of the drum becomes larger. Then, the endless belt is attached to the outer periphery of the expansion / contraction drum, and the nut 15 is tightened to expand the diameter of the expansion / contraction drum at a predetermined ratio, thereby expanding the endless belt.

When the endless belt is vulcanized and molded using a cylindrical mold, the resin or rubber of the elastic layer shrinks during the vulcanization molding, and after the vulcanization molding, the endless belt is attached to the outer periphery of the cylindrical mold. Since the endless belt is in an expanded state as it is, it can be subjected to a heat treatment without vulcanization, while being attached to the cylindrical mold after vulcanization.

Here, the expansion ratio of the endless belt during the heat treatment is appropriately set according to the material forming the elastic layer and the type and form of the reinforcing fiber, and is not particularly limited. Usually, the heat treatment is preferably performed by expanding the distance L between the shafts shown in FIG. 3 to 0.1 to 10%, particularly about 0.1 to 5% as a reference inner peripheral length of the endless belt. In this case, the endless belt attached to the outer periphery of the cylindrical mold as it is after vulcanization molding usually has a thickness of 0.1 to 0.5.
% Expansion rate. As shown in FIG. 3, the above-mentioned distance L between the shafts, which is the reference inner circumferential length of the endless belt, is such that the endless belt 20 is bridged between the pair of shafts 21a and 21b, and one shaft 21b is fixed. In the state, the other shaft 21a is
This is the distance L between the two shafts 21a and 21b in a state where they are separated by the force of g.

According to the manufacturing method of the present invention, the endless belt is subjected to heat treatment in a state where the endless belt is expanded. In this case, the conditions of the heat treatment are the material for forming the elastic layer, the reinforcement, It is appropriately selected according to the type and form of the fiber, the presence or the type of the above-mentioned other resin layer or rubber layer or the above-mentioned coating layer, and is not particularly limited, but is usually 100 to 180 ° C. , 5 to 30 minutes, particularly 120 to 160 ° C. for 10 to 20 minutes. Here, in the case of forming the coating layer, the coating layer can be dried by applying the coating layer on an endless belt and then performing this heat treatment in an expanded state.

[0035]

According to the method of manufacturing an intermediate transfer portion belt of the present invention, a belt obtained by heating a fiber-reinforced endless belt having an elastic layer made of resin or rubber in an expanded state is obtained. It is possible to reduce the variation of the inner circumference and obtain an intermediate transfer belt having excellent dimensional accuracy, and the obtained belt has a small amount of elongation and elongation with time during stretching and driving, and is stable. You can drive.

[0036]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

Example 1 A 0.2 mm-thick canvas impregnated with rubber cement (epichlorohydrin rubber) on the surface and a rubber sheet extruded from the rubber composition shown in Table 1 were molded into an outer diameter of 146 mm. After being wound around the outer periphery of the cylindrical mold and vulcanization-molded, it was demolded to obtain an endless belt having elastic layers formed on both sides of the canvas layer.

[0038]

[Table 1]

On the elastic layer of the obtained endless belt, a coating material obtained by mixing 100 parts by weight of a soluble fluororesin and 25 parts by weight of an isocyanate curing agent was applied to form a coating layer having a thickness of 40 μm. Outer diameter 150mm (perimeter 47
1.2 mm) to expand it.
After the coating layer was dried by heating at 30 ° C. for 15 minutes, it was removed from the expansion / contraction drum to obtain an intermediate transfer belt.

FIG. 3 shows the obtained 30 intermediate transfer belts.
The inner circumference (mm) was measured by the method shown in (1), and the average value (x) and the variation (σ) of the inner circumference were obtained. FIG.
In the above, the force applied to the shaft 21a is from 10 kg to 20 kg.
And elongation (%) is measured and the average value (x)
And the variation in elongation (σ) were determined. Table 2 shows the results.

Example 2 On the elastic layer of the endless belt obtained in the same manner as in Example 1, a paint obtained by mixing 100 parts by weight of fluororubber, 7 parts by weight of a polyol component and 15 parts by weight of magnesium oxide is applied. 20 to 40 μm thick
A rubber layer is formed, and a soluble fluororesin 100
A coating mixture of 25 parts by weight of an isocyanate curing agent is applied to form a coating layer having a thickness of 40 μm, and the coating layer is dried by heating as in Example 1 in an expanded state. Then, an intermediate transfer belt was obtained.

The inner peripheral length (mm) of the obtained 30 intermediate transfer belts was measured in the same manner as in Example 1, and the average value (x), the variation of the inner peripheral length (σ), and the elongation rate (%) were measured. And the variation in elongation (σ) were determined. Table 2 shows the results.

[Example 3] An endless belt was formed in the same manner as in Example 1, and was not attached to the outer periphery of the cylindrical mold without being removed from the cylindrical mold. A coating layer was formed and dried by heating to obtain an intermediate transfer belt.

The inner circumferential length (mm) of the obtained 30 intermediate transfer belts was measured in the same manner as in Example 1, and the average value (x), the variation of the inner circumferential length (σ), and the elongation rate (%) were measured. And the variation in elongation (σ) were determined. Table 2 shows the results.

[Comparative Example] Outer diameter 149.9 mm (outer peripheral length 4
70.9), the endless belt was vulcanized and molded in the same manner as in Example 1, and was released from the mold to form a coating layer similar to that in Example 1 and free without expansion. Then, it was dried by heating to obtain an intermediate transfer belt.

The inner circumferential length (mm) of the obtained 30 intermediate transfer belts was measured in the same manner as in Example 1, and the average value (x), the variation of the inner circumferential length (σ), and the elongation (%) were measured. And the variation in elongation (σ) were determined. Table 2 shows the results.

[0047]

[Table 2]

As shown in Table 2, Examples 1 to 3
In the intermediate transfer belt, the variation in the inner peripheral length is small, and it can be understood that the intermediate transfer belt having excellent dimensional accuracy can be obtained according to the manufacturing method of the present invention. Further, the intermediate transfer belts of Examples 1 to 3 have a small elongation rate and a small variation thereof, are unlikely to cause inconvenience based on elongation occurring during stretching and driving and elongation over time, and can be stably operated. It is recognized that.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of an intermediate transfer device using an intermediate transfer belt.

FIG. 2 shows an example of an expansion / contraction drum used in the method of manufacturing an intermediate transfer belt according to the present invention.
(B) is a right side view.

FIG. 3 is a schematic diagram illustrating a method for measuring the inner circumferential length of a belt.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Intermediate transfer belt 2a-2d Image forming body (photosensitive drum (latent image holding body)) 3 Recording medium 4a-4d Developing device 5 Drive roller 6 Paper feed roller 7 Recording medium conveying device 8 Fixing device 9 Power supply device (Voltage applying means) 11) Expansion / contraction cylinder 12 Urethane resin layer 13 Bolts 14a, 14b Expansion / contraction piece 15 Nut

Claims (5)

[Claims] 1. An intermediate transfer belt disposed between an image forming body and a recording medium, for temporarily transferring and holding a toner image formed on the surface of the image forming body to its own surface, and transferring the toner image to a recording medium. , Wherein a fiber-reinforced endless belt having an elastic layer made of resin or rubber is heat-treated in an expanded state. 2. The intermediate transfer belt according to claim 1, wherein a coating layer is laminated on the elastic layer directly or via another layer, and the coating layer is heated and dried, and the heat treatment is performed at the same time. Manufacturing method. 3. The method for producing an intermediate transfer belt according to claim 1, wherein the endless belt is reinforced with one or more canvas layers. 4. An endless belt is formed by winding and vulcanizing a reinforcing fiber and an elastic layer around an outer periphery of a cylindrical mold, and after removing the endless belt from the cylindrical mold,
The method of manufacturing an intermediate transfer belt according to claim 1, wherein the intermediate transfer belt is mounted on an expansion / contraction drum, expanded to a predetermined diameter, and the heat treatment is performed in this state. 5. The endless belt is formed by winding and vulcanizing a reinforcing fiber and an elastic layer around the outer periphery of the cylindrical mold, and holding the belt around the outer periphery of the cylindrical mold without removing the belt from the cylindrical mold. The method for producing an intermediate transfer belt according to claim 1, wherein the heat treatment is performed in a state where the belt is heated.