JP2011118026A - Method for manufacturing intermediate transfer belt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an intermediate transfer belt having a surface layer which has stable surface roughness (Rz), stable film thickness and is excellent in durability such as abrasion resistance and scuffing resistance due to removal of toner caused by blade after secondary transfer, and to provide the intermediate transfer belt. <P>SOLUTION: In the method of manufacturing intermediate transfer belt having the surface layer on which the primary transfer of a toner image formed on the surface of an electrophotographic photoreceptor is performed, on the surface of an endless belt-like base body, a coating liquid for forming the surface layer is applied onto the surface of the belt base body by using an ultrasonic atomizer while the distance from an ultrasonic atomizer to the surface of the belt-like base body is set to be 20-300 mm. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an intermediate transfer belt used in an electrophotographic image forming apparatus.

  In recent years, electrophotographic image forming apparatuses are strongly required to have high image quality full color and high quality. As is conventionally known, an electrophotographic image forming apparatus includes a charging member that uniformly charges a photosensitive member, an exposure member that forms an electrostatic latent image on the photosensitive member, and an electrostatic latent image that is converted into a toner image. A developing member for developing the toner image, a transfer member for transferring the obtained toner image to the transfer member, a fixing member for fixing the toner image on the transfer member, a cleaning member for cleaning residual toner on the photosensitive member, and an electrostatic on the photosensitive member. It has structural members such as a charge eliminating member that removes the latent image.

  An electrophotographic image forming apparatus supplies charged toner to an electrostatic latent image on a photoconductor in contact or non-contact manner, and transfers a toner image formed through a developing process to make the electrostatic latent image a visible image Then, after the primary transfer onto the intermediate transfer belt, the secondary transfer onto the transfer material and further fixing to form the final image.

  In the transfer process, various mechanical and electrical external forces such as transfer charging and charge removal for primary transfer of the toner image to the intermediate transfer belt material and cleaning with a blade for removing the toner remaining on the intermediate transfer material after transfer are performed. Added to the intermediate transfer belt.

  For this reason, the intermediate transfer belt is required to have various characteristics such as durability against these external forces, that is, mechanical strength, wear resistance, and electrical durability.

  Materials used for the intermediate transfer belt include polycarbonate resin, PVDF (polyvinylidene fluoride), polyalkylene phthalate, PC (polycarbonate) / PAT (polyalkylene terephthalate) blend material, ETFE (ethylene-tetrafluoroethylene copolymer). / PC, ETFE / PAT, PC / PAT blend materials, materials in which a conductive material such as carbon black is dispersed in a thermoplastic resin such as a polyimide resin are known.

  When these thermoplastic resins are used alone, they are inferior in slipperiness, scratch resistance, and cleaning properties. Therefore, it is known that a surface layer is provided to supplement these performances.

  For example, Japanese Patent Application Laid-Open No. 2000-330390 discloses image defects such as color shift and hue change caused by elongation or creep of the intermediate transfer belt material, shortening of the belt life due to belt cracking or breakage, surface resistivity, and the like. It is disclosed that a surface layer made of a resin material in which a conductive agent is dispersed is provided in order to prevent belt deterioration due to a decrease. In JP 2000-330390 A, a water-based emulsion paint containing a fluororesin is dry-coated to prevent the adhesion and roll-up phenomenon and to improve the peelability of the secondary transfer material. A technique for setting the thickness (Rz) in the range of 10 to 30 μm is disclosed.

  Toner is mixed with inorganic fine particles, magnetic powder, ferrite and the like to improve transfer efficiency.

  Even with an intermediate transfer belt that uses such a toner and is provided with a surface layer using conventional techniques, scratches caused by the toner may occur when the toner remaining on the intermediate transfer belt after the secondary transfer is removed with a blade. This is one of the causes of reducing the durability of the intermediate transfer belt.

  For this reason, measures for improving the durability of the surface layer have been studied. For example, a coating liquid using a thermoplastic resin as a base material and using pentaerythritol hexaacrylate containing conductive particles is applied on the base material by a dip coating method, and the surface roughness (Rz) is 0.2 ≦ Rz. A surface layer as a cured film of ≦ 0.5 is known (for example, see Patent Document 1).

When the surface layer described in Patent Document 1 is used, the wear resistance by the blade and the durability against scratches are certainly improved, but it has been found that there are the following problems.
1. Since the variation in the surface roughness (Rz) is not stable, the slipping property and the cleaning property are inferior and the image performance is affected.
2. Since the film thickness is not stable, the surface resistance varies, unevenness occurs in the removal of toner after secondary transfer by the blade, and unevenness in density, increase in fog density, etc. occur after long-term use.

  Under such circumstances, the surface layer has a stable surface roughness (Rz), a stable film thickness, and excellent durability such as abrasion resistance and scratch resistance due to removal of toner by a blade after secondary transfer. Development of an intermediate transfer belt manufacturing method and an intermediate transfer belt manufactured by this manufacturing method is desired.

JP 2007-183401 A

  The present invention has been made in view of such a situation, and an object thereof is a stable surface roughness (Rz), a stable film thickness, and abrasion resistance due to removal of toner by a blade after secondary transfer. Another object of the present invention is to provide an intermediate transfer belt manufacturing method and an intermediate transfer belt having a surface layer excellent in durability such as scratch resistance.

  The above object of the present invention has been achieved by the following constitution.

1. In a method for producing an intermediate transfer belt having a surface layer for primary transfer of a toner image formed on the surface of an electrophotographic photosensitive member on the surface of an endless belt-like substrate,
An ultrasonic atomizer is used as the surface layer forming coating solution for forming the surface layer, and the distance between the ultrasonic atomizer and the surface of the belt-shaped substrate is 20 mm to 300 mm, and the surface layer forming coating solution is formed in the belt shape. A method for producing an intermediate transfer belt, comprising applying to a surface of a substrate.

  2. 2. The method for producing an intermediate transfer belt according to 1 above, wherein the solid content concentration of the coating liquid for forming the surface layer is 5% by mass to 30% by mass.

  3. 3. The method for producing an intermediate transfer belt according to 1 or 2, wherein the coating liquid for forming the surface layer has a viscosity of 2 mPa · s to 50 mPa · s.

  4). When applying the coating solution for forming the surface layer onto the surface of the endless belt-like substrate, the ultrasonic atomizer is applied per second while rotating the endless belt-like substrate at a speed of 600 mm / min to 2000 mm / min. The coating is performed while moving a length corresponding to 50% to 90% of the coating width by the ultrasonic atomizer while moving in a direction perpendicular to the rotational conveyance direction of the endless belt-like substrate. 4. The method for producing an intermediate transfer belt according to any one of 3 above.

  5. 5. The method for producing an intermediate transfer belt according to any one of 1 to 4, wherein a coating width of the ultrasonic atomizer is 5 mm to 200 mm.

  6). 6. The method for producing an intermediate transfer belt according to any one of 1 to 5, wherein the spray amount of the surface layer forming coating solution of the ultrasonic atomizer is 2 ml / min to 350 ml / min.

  Method for producing an intermediate transfer belt having a stable surface roughness (Rz), a film thickness that is stable, and a surface layer having excellent durability such as abrasion resistance and scratch resistance due to removal of toner by a blade after secondary transfer And an intermediate transfer belt could be provided.

1 is a schematic cross-sectional configuration diagram illustrating an example of an electrophotographic image forming apparatus. FIG. 2 is a schematic partial cross-sectional view illustrating a configuration of an intermediate transfer belt illustrated in FIG. 1. FIG. 3 is a schematic view of an example of a manufacturing process for forming a surface layer on the surface of an endless belt-like substrate of an endless intermediate transfer belt. It is the schematic along AA 'shown in the state which has apply | coated with the ultrasonic atomizer of the coating device shown in FIG. FIG. 4 is a flowchart for applying a coating solution for forming a surface layer to the surface of an endless belt-like substrate using an ultrasonic atomizer in the manufacturing process shown in FIG. 3.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 4, but the present invention is not limited thereto.

  FIG. 1 is a schematic sectional view showing an example of an electrophotographic image forming apparatus. This figure shows the case of a full-color image forming apparatus.

  In the figure, reference numeral 1 denotes a full-color image forming apparatus. The full-color image forming apparatus 1 includes a plurality of sets of image forming units 10Y, 10M, 10C, and 10K, an endless belt-shaped intermediate transfer body forming unit 7 as a transfer unit, and an endless belt-shaped paper feeding conveyance for conveying a recording medium P. And a belt type fixing device 24 as fixing means. A document image reading device SC is arranged on the upper part of the main body A of the full-color image forming apparatus 1.

  An image forming unit 10Y that forms a yellow image as one of different color toner images formed on each of the photoreceptors 1Y, 1M, 1C, and 1K is a drum-like photoreceptor as a first image carrier. 1Y, a charging unit 2Y disposed around the photoreceptor 1Y, an exposure unit 3Y, a developing unit 4Y having a developing roller 4Y1, a primary transfer roller 5Y as a primary transfer unit, and a cleaning unit 6Y.

  An image forming unit 10M that forms a magenta image as another different color toner image is disposed around a drum-shaped photoconductor 1M as a first image carrier, and the photoconductor 1M. The charging unit 2M, the exposure unit 3M, the developing unit 4M having the developing roller 4M1, the primary transfer roller 5M as the primary transfer unit, and the cleaning unit 6M.

  Further, an image forming unit 10C for forming a cyan image as one of different toner images of different colors is disposed around a drum-shaped photoreceptor 1C as a first image carrier, and the photoreceptor 1C. The charging unit 2C, the exposure unit 3C, the developing unit 4C having the developing roller 4C1, the primary transfer roller 5C as the primary transfer unit, and the cleaning unit 6C are provided.

  In addition, an image forming unit 10K that forms a black image as one of other different color toner images is disposed around a drum-shaped photosensitive member 1K as a first image carrier, and the photosensitive member 1K. It has a charging means 2K, an exposure means 3K, a developing means 4K having a developing roller 4K1, a primary transfer roller 5K as a primary transfer means, and a cleaning means 6K.

  The endless belt-shaped intermediate transfer body forming unit 7 has an endless intermediate transfer belt 70 as a semiconductive endless belt-shaped second image carrier that is wound around a plurality of rollers and is rotatably supported.

  Each color image formed by the image forming units 10Y, 10M, 10C, and 10K is sequentially transferred and synthesized on the rotating endless intermediate transfer belt 70 by the primary transfer rollers 5Y, 5M, 5C, and 5K. A color image is formed. A recording medium P such as paper as a recording medium accommodated in the paper feeding cassette 20 is fed by the paper feeding / conveying means 21, passes through a plurality of intermediate rollers 22 A, 22 B, 22 C, 22 D, and a registration roller 23, and is secondary. A color image is transferred onto the recording medium P at a time by being conveyed to a secondary transfer roller 5A as a transfer means.

  The recording medium P onto which the color image has been transferred is fixed by the fixing device 24 equipped with the heat roller fixing device 270, is sandwiched between the paper discharge rollers 25, and is placed on the paper discharge tray 26 outside the apparatus.

  On the other hand, after the color image is transferred to the recording medium P by the secondary transfer roller 5A, the residual toner is removed from the endless intermediate transfer belt 70 from which the recording medium P is separated by the curvature by the cleaning means 6A.

  During the image forming process, the primary transfer roller 5K is always in pressure contact with the photoreceptor 1K. The other primary transfer rollers 5Y, 5M, and 5C are in pressure contact with the corresponding photoreceptors 1Y, 1M, and 1C, respectively, only during color image formation.

  The secondary transfer roller 5A comes into pressure contact with the endless intermediate transfer belt 70 only when the recording medium P passes through the secondary transfer roller 5A and secondary transfer is performed.

  Further, the housing 8 can be pulled out from the apparatus main body A through the support rails 82L and 82R. The housing 8 includes image forming units 10Y, 10M, 10C, and 10K, and an endless belt-shaped intermediate transfer body forming unit 7.

  The image forming units 10Y, 10M, 10C, and 10K are arranged in tandem in the vertical direction. An endless belt-shaped intermediate transfer body forming unit 7 is disposed on the left side of the photoreceptors 1Y, 1M, 1C, and 1K in the figure. The endless belt-shaped intermediate transfer body forming unit 7 includes an endless intermediate transfer belt 70 that can be rotated by winding rollers 71, 72, 73, 74, and 76, primary transfer rollers 5Y, 5M, 5C, and 5K, and a cleaning unit 6A. And have.

  The image forming units 10Y, 10M, 10C, and 10K and the endless belt-shaped intermediate transfer body forming unit 7 are integrally pulled out from the main body A by the drawer operation of the housing 8.

  In this manner, the outer peripheral surfaces of the photoreceptors 1Y, 1M, 1C, and 1K are charged and exposed to form a latent image on the outer peripheral surface, and then a toner image (developed image) is formed by development, and an endless belt-like intermediate transfer The toner images of the respective colors are superposed on the body 70, transferred to the recording medium P in a lump, and fixed and fixed by the belt-type fixing device 24 by pressure and heating. In the present invention, the time of image formation includes latent image formation and transfer of a toner image (developed image) to a recording medium P to form a final image.

  The photoreceptors 1Y, 1M, 1C, and 1K after the toner image is transferred to the recording medium P are transferred by the cleaning units 6Y, 6M, 6C, and 6K disposed on the photoreceptors 1Y, 1M, 1C, and 1K. After cleaning the toner remaining on the photoreceptor, the charging, exposure and development cycle described above is entered, and the next image formation is performed.

  In the color image forming apparatus, an elastic blade is used as a cleaning member of the cleaning unit 6A for cleaning the intermediate transfer member. Further, means (11Y, 11M, 11C, 11K) for applying a fatty acid metal salt to each photoconductor is provided. As the fatty acid metal salt, the same fatty acid metal salt as used in the toner can be used.

  FIG. 2 is a schematic partial sectional view showing the configuration of the intermediate transfer belt shown in FIG.

  The configuration of the intermediate transfer belt is not particularly limited, and can be appropriately selected as necessary. Hereinafter, (a) to (d) show typical configurations of the intermediate transfer belt.

  The structure of the intermediate transfer belt shown in FIG.

  In the figure, reference numeral 70a denotes an intermediate transfer belt. The intermediate transfer belt 70 a has a configuration including a base 701 and a surface layer 702.

  The structure of the intermediate transfer belt shown in FIG.

  In the drawing, reference numeral 70b denotes an intermediate transfer belt. The intermediate transfer belt 70b has a configuration including a base 701, an intermediate layer 703, and a surface layer 702. In order to improve the adhesion strength between the substrate 701 and the surface layer 702 and to prevent these layers from being compatible, it is preferable to provide an intermediate layer.

  The structure of the intermediate transfer belt shown in FIG.

  In the drawing, reference numeral 70c denotes an intermediate transfer belt. The intermediate transfer belt 70c has a configuration including a base 701, a first intermediate layer 703a, a second intermediate layer 703b, and a surface layer 702. The strength of the intermediate transfer belt is further increased by multilayering the intermediate layer into the first intermediate layer 703a and the second intermediate layer 703b.

  The structure of the intermediate transfer belt shown in FIG.

  In the drawing, reference numeral 70d denotes an intermediate transfer belt. The intermediate transfer belt 70d has a configuration including a base 701, an elastic layer 704, and a surface layer 702.

The base 701 is preferably formed using a material having a Young's modulus of 200 MPa (200 kg / mm ² ) or higher, and more preferably a material of 300 MPa (300 kg / mm ² ) or higher. The thickness of the substrate 701 is preferably 20 μm to 150 μm. The thickness of the surface layer is preferably 0.1 μm to 10 μm. The thickness of the intermediate layer is preferably 20 μm to 200 μm. The thickness of the elastic layer is preferably 50 μm to 500 μm, more preferably 80 μm to 200 μm.

  The physical properties of the intermediate transfer belt shown in this figure are shown below.

The surface resistivity of the belt surface takes into consideration the suppression of local peeling discharge at the point where the recording medium and the intermediate transfer belt peel, and the uniform electric field strength at the point where the recording medium and the intermediate transfer member start to contact each other. And preferably 1 × 10 ¹⁰ Ω / □ to 1 × 10 ¹⁴ Ω / □.

  The surface resistivity can be measured based on JIS K6991 using a circular electrode (for example, “HR probe” of Hirester IP manufactured by Mitsubishi Oil Chemical Co., Ltd.).

  The surface energy of the surface layer is preferably 30 mN / m or less in consideration of toner adhesion and image formation.

The volume resistivity of the intermediate transfer belt is 1 × 10 ⁸ Ω · cm to 1 × 10 ¹² Ω · cm in consideration of the electrostatic repulsion between the toners and the influence of the fringe electric field near the image edge. It is preferable. The volume resistivity can be measured based on JIS K6991 using a circular electrode (for example, HR probe of Hirester IP manufactured by Mitsubishi Yuka Co., Ltd.) in the same manner as the surface resistivity described above.

Surface hardness of the intermediate transfer belt is preferably 130N / mm ² from 85N / mm ^2. Here, the surface hardness can be obtained by a method of measuring how much the indenter has entered the sample with a Vickers indenter widely used for measuring the hardness of a metal material. When the test load P (mN) and the amount of penetration of the indenter into the sample (indentation depth) D (μm), the surface hardness DH is defined by the following formula (3).

Formula (3)
DH≡αP / D ²
Here, α is a constant depending on the shape of the indenter, and α = 3.8854 (used indenter: in the case of a Vickers indenter).

  This surface hardness is the hardness obtained from the excessive weight and indentation depth in the process of indenting the indenter, and represents the strength characteristics of the material in a state including not only plastic deformation of the sample but also elastic deformation. . Note that the measurement area is very small.

The micro surface hardness on the transfer surface of the intermediate transfer member is measured by universal hardness in accordance with DIN 50 359. Specifically, it was measured with a micro hardness tester H100 (manufactured by Fisher Instruments) and analyzed by the program WIN-HCU. The measurement conditions are as follows.
Measurement environment: 23 ° C, 55% RH
Working indenter: Vickers indenter load speed: 10 mN / 20 sec
Maximum pushing depth: 0.5μm
The present invention relates to a manufacturing method of an endless intermediate transfer belt shown in FIGS. 1 and 2 having at least one surface layer on a substrate, and an intermediate transfer belt manufactured by this manufacturing method.

  FIG. 3 is a schematic view of an example of a manufacturing process for forming a surface layer on the surface of an endless belt-like substrate of an endless intermediate transfer belt. FIG. 3A is a schematic perspective view of an example of a manufacturing process for forming a surface layer on the surface of an endless belt-like substrate of an endless intermediate transfer belt. FIG. 3B is a schematic plan view of an example of the manufacturing process shown in FIG.

  In the figure, 9 indicates a manufacturing process. The manufacturing process 9 has a holding part 9a and an application part 9b. The holding portion 9a includes a rotatable first holding roller 9a1, a rotatable second holding roller 9a2, and a holding member 9a3 that holds the flatness of the base 701. In this figure, the second holding roller 9a2 is for driving, and the first holding roller 9a1 is for tension adjustment. Whether the first holding roller 9a1 and the second holding roller 9a2 are used for driving and tension adjustment can be appropriately set according to need. The endless belt-like substrate 701 is rotatable by the rotation of the second holding roller 9a2 for driving while being held by the first holding roller 9a1 and the second holding roller 9a2.

  The holding member 9a3 includes a first holding roller 9a1 and a second holding roller 9a2 in order to suppress shaking and fluttering of the endless belt-like substrate 701 that rotates while being held by the first holding roller 9a1 and the second holding roller 9a2. Is disposed so as to be in contact with the back surface of the endless belt-like substrate 701. Further, the surface of the holding member 9a3 that contacts the back surface of the base 701 is provided with a plurality of holes (not shown) that do not affect the flatness of the base 701, and the inside of the holding member 9a3 affects the transport of the base 701. It is preferable that the pressure is reduced to such an extent that the endless belt-like substrate 701 can be sucked and held by the holding member 9a3.

  The application unit 9b includes an ultrasonic atomizer 9b1 and a drive unit 9b2 of the application apparatus. Reference numeral 9b11 denotes a coating solution supply pipe for supplying the surface layer forming coating solution to the ultrasonic atomizer 9b1. The ultrasonic atomizer 9b1 is attached to the guide rail 9b4 by an attachment member 9b12 so as to be movable in a direction perpendicular to the conveying direction of the endless belt-like base 701. In this figure, the coating liquid supply unit and the control unit for the ultrasonic atomizer 9b1 are omitted.

  The drive unit 9b2 has a motor 9b21 and a guide rail mounting plate 9b3. The guide rail mounting plate 9b3 is provided with two guide rails 9b4 for mounting the mounting member 9b12 and moving the endless belt-like base body 701 held by the holding portion 9a in a direction perpendicular to the conveying direction. Has been.

  The motor 9b21 is screwed into a slide screw 9b13 mounted on the mounting member 9b12, and has a female screw having a length that moves the mounting member 9b12 longer than the width of the endless belt-like base body 701 held by the holding portion 9a. 9b22.

  By driving the motor 9b21, the ultrasonic atomizer 9b1 attached to the attachment member 9b12 can move in a direction perpendicular to the conveying direction of the endless belt-like substrate 701 as the slide screw 9b13 rotates. It has become.

  This figure shows a coating apparatus in which coating is performed by rotating the endless belt-shaped substrate 701 and reciprocating the coating apparatus in a direction perpendicular to the conveying direction of the endless belt-shaped substrate 701.

  In this figure, the endless belt-like substrate 701 is held by the first holding roller 9a1 and the second holding roller 9a2. However, instead of the first holding roller 9a1 and the second holding roller 9a2, an endless belt shape is used. The endless belt-like base 701 may be held on a cylindrical (columnar) frame having the same diameter as the base 701 and the frame may be rotated.

  A commercially available ultrasonic atomizer 9b1 can be used. Examples thereof include an ultrasonic atomizer (manufactured by Tick Corporation), an ultrasonic spray coating apparatus (manufactured by USI), and an ultrasonic spray nozzle system (manufactured by Sonotech).

  As a manufacturing method of the endless belt-like substrate 701, for example, a method in which a polyamic acid solution is immersed in an outer peripheral surface of a cylindrical mold, a method in which the polyamic acid solution is applied to the inner peripheral surface, a method in which centrifugation is further performed, or a casting mold is filled A method of developing the ring by an appropriate method such as a method, drying the formed layer into a bell-shaped shape, heat-treating the molded product to convert the polyamic acid into an imide, and recovering it from the mold (E.g., JP-A 61-95361, JP-A 64-22514, and JP-A 3-180309). In forming the endless belt, an appropriate treatment such as mold release treatment or defoaming treatment can be performed.

  FIG. 4 is a schematic view taken along the line A-A ′ showing a state in which application is performed by the ultrasonic atomizer of the application apparatus shown in FIG. 3. FIG. 4A is a schematic cross-sectional view along A-A ′ showing a state in which application is performed by the ultrasonic atomizer of the application apparatus shown in FIG. 3. FIG. 4B is a schematic enlarged plan view of a portion indicated by P in FIG. In this figure, the mounting member, guide rail, slide screw, etc. are omitted.

  In the figure, J indicates the distance from the spray port 9b1a of the ultrasonic atomizer 9b1 to the surface of the endless belt-like substrate 701. The distance J is 20 mm to 300 mm.

  When the thickness is less than 20 mm, the droplet sprayed from the spray port bounces off from the base material, resulting in non-uniform film thickness and surface roughness.

  In the case of exceeding 300 mm, the droplet sprayed from the spray port 9b1a is affected by the wind (environment), deviates from the desired position, and the film thickness and the surface roughness are not preferable.

  K indicates the width of the circular application region L formed on the endless belt-like substrate 701 by the droplets sprayed from the spray port 9b1a. The width K indicates the diameter of the application region L and also indicates the application width. The width K is preferably 5 mm to 200 mm in consideration of the coarsening of the droplets due to the adjacent droplets, the gap between the droplets, the stabilization of the film thickness and the surface roughness, and the like.

  M indicates the periphery of a circular application region L. N indicates the center of the circular application region L.

  The solid content concentration of the coating liquid for forming the surface layer supplied from the coating liquid supply pipe 9b11 to the ultrasonic atomizer 9b1 takes into consideration wet film thickness, film thickness unevenness during belt conveyance, film thickness control, surface roughness, etc. The content is preferably 5% by mass to 30% by mass.

  The viscosity of the coating solution for forming the surface layer is preferably 50 mPa · s or less in consideration of droplet forming properties. More preferably, it is 2 mPa · s to 50 mPa · s.

  When the surface layer forming coating solution is applied, the transport speed of the endless belt-like substrate 701 is 2000 mm / min or less in consideration of the film thickness, surface roughness, etc. due to the influence of a cold during transport to the droplets. It is preferable to do. More preferably, it is 600 mm / min to 2000 mm / min.

  When the surface layer forming coating solution is applied, the length of the ultrasonic atomizer 9b1 that moves in the direction perpendicular to the conveying direction of the endless belt-like substrate 701 is the length of the ultrasonic atomizer 9b1 that moves to the droplets. Taking into account the film thickness, surface roughness, etc. due to the influence of the cold, the length corresponding to 50% to 90% of the coating width by the ultrasonic atomizer is preferable. Specifically, when the width K is 80 mm, the ultrasonic atomizer 9b1 moves from 40 mm / sec to 72 mm / sec.

  The number of times the surface layer forming coating solution is applied to the surface of the endless belt-like substrate 701 is preferably set as necessary. The number of times of application is that the ultrasonic atomizer 9b1 starts application at the application start point at the end of the endless belt-like substrate 701, moves to the opposite end, and is applied over the entire length of the entire width of the endless belt-like substrate 701. This is the number of times that the time is one application.

  When the surface layer forming coating solution is applied, the spray amount from the ultrasonic atomizer 9b1 is preferably 350 ml / min or less in consideration of droplet formation, dripping, and droplet splashing from the belt surface. . More preferably, it is 2 ml / min to 350 ml / min.

  Next, FIG. 5 shows a flow of applying the surface layer forming coating solution to the surface of the endless belt-like substrate using an ultrasonic atomizer in the manufacturing process shown in FIG.

  FIG. 5 is a flowchart for applying the surface layer forming coating solution to the surface of the endless belt-like substrate using an ultrasonic atomizer in the manufacturing process shown in FIG. In this figure, the ultrasonic atomizer is omitted.

  The coating method using the ultrasonic atomizer according to the method of manufacturing the intermediate transfer belt of the present invention is performed by rotating the endless belt-shaped substrate and moving the ultrasonic atomizer in a direction orthogonal to the rotational movement direction of the endless belt-shaped substrate. Is the method.

  Step 1 shows an application start state in which an ultrasonic atomizer is set at the application start point and the surface layer forming application liquid is applied. At this time, the side M of the circular spray region L is set to be a preset position at the end of the endless belt-like substrate. The application start point is the center N of the spray region L.

  Step 2 shows a state several minutes after the application of the coating solution for forming the surface layer is started. Application is performed while the endless belt-like substrate 701 and the ultrasonic atomizer 9b1 (not shown) move simultaneously (the spray region L moves). The endless belt-like substrate 701 is preferably rotated and moved in the direction of arrow a at a speed of 600 mm / min to 2000 mm / min. The ultrasonic atomizer corresponds to 50% to 90% of the application width (the width K of the application region L shown in FIG. 4) by the ultrasonic atomizer per second in the direction orthogonal to the rotational movement direction of the endless belt-like substrate 701. It is preferable to move the length. This figure shows a length corresponding to 50% of the application width (width K of the application region L shown in FIG. 4) per second in the direction orthogonal to the rotational movement direction of the endless belt-like substrate 701. The state which is apply | coating while moving is shown.

  Step 3 shows a state in which the ultrasonic atomizer has moved and the periphery M of the spray region L has reached a position set at the end opposite to the end where the endless belt-like substrate 701 starts.

  Step 4 is a state in which the endless belt-like substrate 701 is rotated once from the state of Step 3 and the surface layer forming coating solution is applied to the entire surface of the endless belt-like substrate 701 (however, the areas where both ends are not applied are left). Indicates.

  In the present invention, the state shown in step 4 is referred to as one application. Thereafter, if necessary, the ultrasonic atomizer is moved toward the end of the endless belt-like substrate 701 that has started coating (in the direction of arrow c in the figure), and the thickness set by repeating the operations from step 2 to step 3 is set. It is possible to form a surface layer.

The following effects were obtained by applying the surface layer forming coating solution to the surface of the endless belt-like substrate using an ultrasonic atomizer at a distance from the surface of 20 to 300 mm to form the surface layer.
1) It was possible to form a surface layer having stable surface roughness without aggregation of conductive particles.
2) A stable surface layer can be formed.

  Next, the material constituting the endless intermediate transfer belt of the present invention will be described.

(Endless belt base)
For example, polycarbonate, polyphenylene sulfide (PPS), PVDF (polyvinylidene fluoride), polyimide, PEEK (polyether ether ketone), polyester, polyether ether ketone, polyamide, polyphenylene sulfide, polycarbonate, polyvinylidene fluoride (PVDF), poly Examples thereof include resin materials such as fluoroethylene-ethylene copolymer (ETFE) and resin materials containing these as main raw materials. Furthermore, it is also possible to use a material obtained by blending these resin materials and elastic materials.

  Examples of the elastic material include polyurethane, chlorinated polyisoprene, NBR, chloropyrene rubber, EPDM, hydrogenated polybutadiene, butyl rubber, and silicone rubber. These may be used alone or in combination of two or more.

  Among the resin materials, polyimide resin is preferable from the viewpoint of mechanical properties. Specifically, as a polyimide resin material, a polypyromellitic acid imide resin material such as DuPont Kapton HA, a polybiphenyltetracarboxylic acid imide resin material such as Ube Industries, Upilex S, Polybenzophenone tetracarboxylic imido acid resin materials such as Upilex R of Ube Industries, Ltd., LARC-TPI (thermoplastic polyimide resin) of Mitsui Toatsu Chemical Industries, Ltd., and the like.

  Examples of materials that can be used for the intermediate layer shown in FIG. 2B include copolymer resins of vinyl chloride, vinyl acetate, and maleic acid, and polyamide resins. Specific examples of the polyamide resin include N-methoxymethylated nylon (hereinafter abbreviated as “nylon 8”), nylon 12, and copolymer nylon.

  As the solvent for the polyamide resin, a single solvent such as methanol or ethanol, a mixed solvent obtained by mixing water, toluene, or the like with these single solvents, 1-propanol, 2-propanol, or the like is used. Among these, a combination of nylon 8 and a methanol / water mixed solvent (methanol / water = 3/1) is preferable.

  In the case of the first intermediate layer 703a and the second intermediate layer 703b shown in FIG. 2C, it is preferable to use the resin material of the above-described intermediate layer for the second intermediate layer 703b. In addition to the polyimide resin and polyamide resin described above, resin materials that can be used for the first intermediate layer 703a include vinylidene fluoride-tetrafluoroethylene copolymer, ethylene-tetrafluoroethylene copolymer, poly Examples of the fluororesin include chlorotrifluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.

Surface layer As the resin material for forming the surface layer, it is preferable to use a material having a low surface energy in order to promote separation of the toner image from the surface of the intermediate transfer belt. Examples of the material having low surface energy include a fluorine-based material, a silicone-based material, or a material containing these as a main component, a fluorine resin powder, a silicone resin, and a material obtained by dispersing a silicone oil component.

  Among these, a silicone resin is preferable. The silicone resin is not particularly limited, but a liquid silicone resin is usually preferable from the viewpoint of work efficiency, and examples include those containing an organic solvent such as n-hexane and reactive types that do not use an organic solvent. In particular, a hard type one-component or two-component curable silicone resin is preferable. Of these, thermosetting silicone resins (methyl) and room temperature curable silicone resins are preferred. The material added to the surface layer will be described.

  It is preferable to add a conductive material to the surface layer for the purpose of improving conductivity, eliminating the occurrence of local peeling discharge during secondary transfer, and avoiding image defects.

(Conductive fine particles)
It is possible to add conductive fine particles in which a thin metal layer is coated on the surface of the resin fine particles. Examples of the method for producing conductive fine particles include a method in which a metal layer is coated with resin fine particles having a porous surface, resin fine particles that have been subjected to etching treatment with acid or alkali, and metal on the resin fine particle surfaces. The method of plating is mentioned. Also, the method for producing conductive fine particles by electroless plating disclosed in JP-A-8-31655, JP-A-2001-247974, etc. is good without performing treatment such as making porous or modifying surface properties. Since adhesion is obtained, it is preferable.

  As the resin fine particle material constituting the conductive fine particles, a resin material that does not dissolve in a water-soluble organic solvent or an electroless plating solution used when the metal layer is coated and does not swell at most is used. Specifically, a resin material that forms a crosslinked structure is particularly preferable.

  Examples of the polymerizable monomer that forms a resin material having a crosslinked structure include divinylbenzene, hexatriene, divinyl ether, divinyl sulfone, diallyl carbinol, alkylene diacrylate, oligo or polyalkylene glycol diacrylate, oligo or polyalkylene. Glycol dimethacrylate, alkylene triacrylate, alkylene tetraacrylate, alkylene trimethacrylate, alkylene tetramethacrylate, alkylene bisacrylamide, alkylene bismethacrylamide, both end acrylic modified polybutadiene oligomers are polymerized alone or with other polymerizable monomers Reticulated polymer obtained: phenol formaldehyde resin, melamine formaldehyde resin, benzoguanamine formaldehyde resin, urea Thermosetting resins such as Le formaldehyde resins.

  The method for synthesizing the polymer having a crosslinked structure is not particularly limited. For example, the polymer can be formed by appropriately selecting a known synthesis method such as a suspension polymerization method, an emulsion polymerization method, a seed polymerization method, or a dispersion polymerization method. . In addition to the resin material forming the cross-linked structure, resin particles containing at least one of polystyrene, polystyrene copolymer, polyacrylate ester, and polyacrylate ester copolymer can also be used.

  The particle diameter of the resin fine particles is 0.5 μm to 50.0 μm, preferably 0.5 μm to 25.0 μm. The amount of the metal-coated resin fine particles contained in the surface layer is 20 to 80 per unit area in consideration of necessary conductivity, transfer failure, and transfer rate, preferably 30 To 70.

  The metal that can be coated on the surface of the resin fine particles is not particularly limited, and examples thereof include Au, Ag, Co, Ni, Pd, Pt, and Sn. These metals may be alloys or two or more types of multilayer coatings.

  The thickness of the metal layer is preferably 5 nm to 100 nm, more preferably 10 nm to 80 nm in consideration of the development of conductivity.

(Metal alkoxide compound)
Formula _{(1) M (O-C} n H 2n + 1) m
In the formula, M is any one of silicon, aluminum, zirconium or titanium, and m is the valence of M. The compound represented by the general formula (1) is a metal alkoxide compound of silicon, aluminum, zirconium, or titanium. Among them, a tetraalkoxysilane compound of the following general formula (2) in which M is silicon is preferably used. It is done.

General formula (2) Si (O—C _n H _{2n + 1} ) ₄
In the tetraalkoxysilane compound, the alkoxy group in the formula is an alkoxy group having 1 to 8, preferably 1 to 4 carbon atoms. Specific examples of the tetraalkoxysilane compound include tetramethoxysilane, tetraethoxysilane, and tetrabutoxysilane.

  Specific examples of usable metal alkoxides other than the above include tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane, and tetraphenoxysilane. Examples of the alkoxytitanium compound include tetramethoxytitanium, tetraethoxytitanium, and tetraisopropoxytitanium. Examples of the alkoxyaluminum compound include trimethoxyaluminum, triethoxyaluminum, triisopropoxyaluminum, and tributoxyaluminum.

  Furthermore, examples of the alkoxyzirconium compound include tetraethoxyzirconium, tetraisopropoxyzirconium, and tetra-n-butoxyzirconium.

  In addition, although what is formed using the compound represented by the general formula (1) and (2) mentioned above is contained, here, the compound represented by the general formula (1) and (2) is used. The term “formed” means a case where the above compound is contained alone or a case where these compounds and a binder resin are combined by a coupling reaction or the like.

(Conductive substance that imparts electron conductivity)
Examples of the conductive substance that imparts electron conductivity include carbon black, graphite, aluminum, nickel, copper alloys and other metals or alloys, tin oxide, zinc oxide, potassium titanate, tin oxide-indium oxide, or tin oxide- Examples thereof include metal oxides such as antimony oxide composite oxide. Among these, carbon black such as furnace black, ketjen black, and channel black are representative. Specifically, granular acetylene black manufactured by Electrochemical Co., Ltd., HS-500 manufactured by Asahi Carbon Co., Ltd., Asahi Thermal FT, Asahi Thermal MT, Ketjen Black manufactured by Lion Azo Co., Ltd., Vulcan XC- manufactured by Cabot Co., Ltd. 72, SPECIAL BLACK4 manufactured by Degussa, and the like. These carbon blacks may be used alone or in combination of two or more.

  The content of the electron conductive conductive material is preferably 4 parts by mass to 20 parts by mass, and more preferably 5 parts by mass to 15 parts by mass with respect to 100 parts by mass of the binder resin in the surface layer. By setting the content of the electron-conductive conductive substance in the above range, moderate electron conductivity is imparted to the surface layer.

(Conductive substance that imparts ion conductivity)
Examples of the ion conductive conductive material include various (for example, styrene) copolymers with (meth) acrylates that bind a quaternary ammonium base to a carboxyl group, and copolymers of maleimide and methacrylate that bind to a quaternary ammonium base. Polymers that bind quaternary ammonium bases such as polymers, polymers that bind alkali metal salts of sulfonic acids found in sodium polysulfonates, polymers that bind at least alkyl oxide hydrophilic units in the chain, such as poly Examples include various surfactants such as ethylene oxide, polyethylene glycol-polyamide copolymer, polyethylene-epichlorohydrin copolymer, polyether amide imide, and block polymer having a polyether segment. These may be used alone or in combination of two or more. Further, an ion conductive material and the above-described electron conductive material may be combined, and a stable electric resistance value can be obtained.

  The content of the ion conductive conductive material is preferably 0.5 parts by mass to 30 parts by mass and more preferably 1 part by mass to 20 parts by mass with respect to 100 parts by mass of the binder resin in the surface layer.

(Conductive filler)
By containing conductive or semiconductive fine powder called conductive filler in each layer constituting the intermediate transfer belt, the resistivity of the intermediate transfer belt can be adjusted and resistance variation can be suppressed. By assisting the contained conductive resin fine particles, it is possible to more effectively suppress the occurrence of electric field concentration due to the transfer voltage.

Usable conductive fillers include, for example, conductive powder such as carbon black, metal powder such as aluminum powder, nickel powder, and stainless steel powder, c-ZnO, c-TiO ₂ , c-ZnO ₄ , and c-SnO _2. And conductive metal oxides such as graphite, quaternary ammonium salts, phosphate esters, sulfonates, aliphatic polyhydric alcohols, aliphatic alcohol sulfate salts, and the like. Among these conductive fillers, carbon black such as ketjen black and acetylene black, c-TiO ₂ , and c-SnO ₂ that can provide good dispersion stability are preferable. Note that “c−” means conductivity. These conductive fillers may be used alone or in combination of two or more. Next, an image forming apparatus that can use the intermediate transfer belt of the present invention will be described.

  Examples of the image forming apparatus capable of using the intermediate transfer belt of the present invention include a copying machine and a laser printer. In particular, an image forming apparatus that performs continuous printing of 5000 sheets or more is included. In such image formation, an electric field is frequently generated between the intermediate transfer belt and the recording paper, but image defects are generated by using the intermediate transfer belt according to the method of manufacturing the intermediate transfer belt of the present invention. Stable secondary transfer is realized without causing it to occur.

  An image forming apparatus usable in the present invention includes an image carrier that forms an electrostatic latent image according to image information, a developing device that visualizes the electrostatic latent image formed on the image carrier using toner, and an image carrier. Primary transfer means for transferring the toner image carried on the intermediate transfer belt to the intermediate transfer belt manufacturing method of the present invention, and secondary transfer means for transferring the toner image on the intermediate transfer belt onto a recording medium such as paper or an OHP sheet And have. By providing the intermediate transfer belt of the present invention as an intermediate transfer member, stable image formation can be performed without causing image defects due to peeling discharge.

  The intermediate transfer type image forming apparatus that can be used in the present invention is not particularly limited. For example, a monochrome image forming apparatus that forms an image using only a single color toner or an image carrier such as a photosensitive drum. An apparatus for forming a color image by sequentially repeating the primary transfer of the toner image carried on the intermediate transfer member, and a tandem in which a plurality of image carriers having developing units for respective colors are arranged in series on the intermediate transfer member And a so-called mold color image forming apparatus.

(Elastic layer)
As the material used for the elastic layer, for example, conductive material particles such as carbon black and various metal powders are blended in a rubber material such as chloroprene rubber, polybutadiene rubber, isoprene rubber, urethane rubber, EPDM, acrylic rubber, and silicone rubber. In addition, a material having a volume resistivity adjusted to a range of 10 ^8.5 Ω · cm to 10 ^11.5 Ω · cm can be given.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

Example 1
An intermediate transfer belt having the substrate / surface layer structure shown in FIG. 2A was produced by the method described below.

(Production of endless belt-like substrate)
N-methyl-2-pyrrolidone (NMP) solution of polyamic acid composed of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA) and p-phenylenediamine (PDA) (European made by Ube Industries) S (solid content: 18% by mass)) and dried oxidized carbon black (SPECIAL BLACK4 (Degussa, pH 3.0, volatile content: 14.0%)) with respect to 100 parts by mass of the polyimide resin solid content. , Added to 23 parts by mass, using a collision type disperser (GeanusPY made by Seanas), with a pressure of 200 MPa, a minimum area of 1.4 mm ² , colliding after two divisions, and again passing through the path dividing into two parts five times And mixed to obtain a polyamic acid solution containing carbon black.

  The polyamic acid solution containing carbon black is applied to the inner surface of the cylindrical mold to a thickness of 0.5 mm via a dispenser, rotated at 1500 rpm for 15 minutes to form a spread layer having a uniform thickness, and then rotated at 250 rpm. Hot air at 60 ° C. was applied for 30 minutes from the outside of the mold, and then heated at 150 ° C. for 60 minutes. Thereafter, the temperature was raised to 360 ° C. at a rate of 2 ° C./min, and further heated at 360 ° C. for 30 minutes to remove the solvent, remove dehydrated ring-closing water, and complete the imide conversion reaction. Thereafter, the temperature was returned to room temperature, and the mold was peeled from the mold to produce an endless belt-like substrate having a total thickness of 0.1 mm.

(Formation of surface layer)
(Preparation of coating solution for surface layer formation)
Preparation of Organopolysiloxane Resin A Solution 136 g of monomethyltrimethoxysiloxane, 200 g of toluene, and 0.9 g of sodium hydroxide were placed in a 1 L (liter) flask, and 20 g of water was added with stirring. After aging at 40 ° C. for 2 hours and then at 70 ° C. for 2 hours, the solution was concentrated to 285 g at normal pressure. The siloxane concentration in this concentrate was 40%, and about 70 g of methanol was contained in the fraction. Next, 7 g of concentrated hydrochloric acid and 25 g of water were added to the concentrated solution at 40 ° C., and the mixture was aged by stirring at 40 ° C. for 2 hours. Subsequently, washing with water with 100 g of 10% aqueous sodium sulfate was repeated three times to adjust the pH of the system to 7. The concentration of the obtained organopolysiloxane (272 g) is 40%, and this solution is referred to as “resin A solution”.

(Preparation of carbon black master A solution)
Furnace carbon black (average primary particle size 21 nm, BET specific surface area 242 m ² / g, DBP oil absorption 169 ml / g, pH 7.0, volatile content 1.0%) 30 g
Acrylic dispersion aid (solid content 30%) 10g
MEK (methyl ethyl ketone) 160g
Cyclohexane 40g
The above composition was dispersed with a sand grinder at 1000 rpm for 1 hour to obtain a carbon black master A solution.

  100 g of the resin A solution, 2 g of tetramethoxysilane, 80 g of MEK, and 20 g of methyl isobutyl ketone are added and dispersed and mixed in a sand mill for 20 minutes at 1000 rpm to obtain a coating solution for forming a surface layer having a solid content of 7.8% by mass. It was.

  The viscosity was 20 mPa · s. The viscosity is a value measured with a viscotech rotary viscometer.

(Application of coating solution for surface layer formation)
An ultrasonic atomizer (manufactured by Tick Corporation) is used as the coating apparatus shown in FIG. 3 on the surface of the prepared endless belt-like substrate. Table 1 shows the distances from the ejection port of the coating liquid discharge nozzle to the surface of the charge transport layer. After coating the coating solution for forming the surface layer, which was changed and prepared as shown in FIG. 2, the surface layer was coated so that the dry film thickness was 5 μm. The drying and heat treatment conditions at this time were as follows: after application, rotating at room temperature for 5 minutes, and then heat treating at 120 ° C. for 60 minutes to produce an intermediate transfer belt. 101 to 106.

  In addition, the coating method of the surface layer forming coating solution was repeated step 1 to step 4 shown in FIG. 5 five times. Further, the endless belt-like substrate was rotated and moved at 1200 mm / min, and the ultrasonic atomizer was applied while moving at 1.1 mm / sec in a direction perpendicular to the rotational conveyance direction of the endless belt-like substrate. .

  Other coating conditions for the surface layer forming coating solution are shown below.

Discharge nozzle diameter: 2mm
Ultrasonic frequency: 100 kHz
Average droplet diameter: 200 μm
Spray amount: 100 ml / min
Number of coatings: 5 times Evaluation Table 1 shows the results of evaluation according to the evaluation ranks shown below, which are attached to the film thickness stability, surface roughness stability, and durability according to the evaluation ranks shown below.

Film thickness stability The film thickness of the surface layer was measured at 60 points in the longitudinal direction and 20 points in the width direction, and the variation in film thickness was determined by calculation from the formula shown below to determine the film thickness stability. The film thickness was measured by MMS manufactured by Fisher Instruments Co., Ltd.

Variation in film thickness (%) = ((maximum film thickness−minimum film thickness) / average film thickness) × 100
Evaluation rank of film thickness stability ○: Less than 5% △: 5% or more, less than 9% ×: 9% or more Surface roughness stability The surface roughness of the surface layer was measured at 20 points in the longitudinal direction and 10 points in the width direction. The variation of the surface roughness was calculated from the formula shown below and determined as the surface roughness stability. The surface roughness was measured with a surface roughness profile measuring machine Surfcom 1400D manufactured by Tokyo Seimitsu Co., Ltd.

Variation in surface roughness (%) = ((maximum surface roughness−minimum surface roughness) / average surface roughness) × 100
Evaluation rank of surface roughness stability ○: Less than 11% △: 11% or more, less than 21% ×: 21% or more Durability An intermediate transfer belt is applied to a commercially available full-color multifunction machine “8050 (manufactured by Konica Minolta Business Technologies)”. Load one by one and print 100,000 sheets of A4 size originals on a high-quality paper (64 g / m ² ) with a white background, solid black, red, green, and blue solid images, and a quarter each. The obtained prints were evaluated for unevenness in image density and used as a substitute evaluation for durability. The photosensitive member was cleaned using a polyurethane elastic blade having a thickness of 2 mm.

Image density unevenness From the start of printing, it was applied to 10 prints every 10,000 sheets, and the presence or absence of density unevenness of a solid black image was visually evaluated.

Evaluation rank of image density unevenness ○: Image density unevenness is good and good △: Image density unevenness is faintly recognized but practically no problem ×: Image density unevenness is clearly recognized and practically problematic level The value measured by MMS made by Fisher Instruments Co., Ltd. is shown.

  Sample No. 2 was prepared by applying a surface layer forming coating solution using an ultrasonic atomizer and setting the distance between the jet outlet and the surface of the substrate to 20 to 300 mm of the present invention. It was confirmed that all of Nos. 102 to 105 showed excellent performance in film thickness stability, surface roughness stability, and durability.

  Sample No. 1 was prepared by applying a coating solution for forming a surface layer using an ultrasonic atomizer and setting the distance between the jet outlet and the surface of the substrate to 10 mm of the present invention. No. 101 had a large variation in surface roughness, resulting in poor cleaning properties due to poor cleaning performance and unevenness in image.

  Sample No. 1 was prepared by applying a surface layer forming coating solution using an ultrasonic atomizer and setting the distance between the jet outlet and the surface of the substrate to 310 mm of the present invention. No. 106 resulted in poor film durability and poor surface durability due to large variations in film thickness stability and surface roughness, resulting in poor cleaning properties and image unevenness. The effectiveness of the present invention was confirmed.

Example 2
An intermediate transfer belt having the substrate / surface layer structure shown in FIG. 2A was produced by the method described below.

(Production of endless belt-like substrate)
The same endless belt-like substrate as in Example 1 was produced.

(Formation of surface layer)
(Preparation of coating solution for surface layer formation)
When the surface layer forming coating solution used in Example 1 was prepared, the surface layer forming coating solution was prepared in the same manner except that the solid content concentration was changed as shown in Table 2. In addition, solid content concentration was performed by changing the addition amount of MEK and a cyclohexane. The viscosity was adjusted by adjusting the amount of the thickener to be constant.

(Application of coating solution for surface layer formation)
The prepared coating solution for forming the surface layer was prepared using the sample No. 1 of Example 1. No. 103 was coated on an endless belt-like substrate prepared under the same coating conditions as in the production of the intermediate transfer belt. 201 to 206.

Evaluation The produced sample No. Table 2 shows the results of evaluation according to the same evaluation rank as that of Example 1 in terms of film thickness stability, surface roughness stability, and durability of 201 to 206.

  When applying the coating solution for forming the surface layer using an ultrasonic atomizer and setting the distance between the jet outlet and the surface of the substrate to 50 mm of the present invention, the solid content concentration of the coating solution for forming the surface layer is from 5% by mass to 30% by mass. %, It was confirmed that all showed excellent performance in film thickness stability, surface roughness stability, and durability. The effectiveness of the present invention was confirmed.

Example 3
An intermediate transfer belt having the substrate / surface layer structure shown in FIG. 2A was produced by the method described below.

(Production of endless belt-like substrate)
The same endless belt-like substrate as in Example 1 was produced.

(Formation of surface layer)
(Preparation of coating solution for surface layer formation)
When preparing the surface layer forming coating solution used in Example 1, as shown in Table 2, the surface layer forming coating solution was prepared in the same manner except that the viscosity was changed. The viscosity was changed by changing the amount of thickener added. The viscosity indicates a value measured with a rotational viscometer manufactured by Viscotec Corporation.

(Application of coating solution for surface layer formation)
Sample No. 1 of Example 1 The surface layer-forming coating solution prepared under the same coating conditions as those used when preparing the No. 103 was coated on the prepared endless belt-like substrate to prepare an intermediate transfer belt. 301 to 306.

Evaluation The produced sample No. Table 3 shows the results of evaluation in accordance with the same evaluation rank as in Example 1 with respect to film thickness stability, surface roughness stability, and durability of 301 to 306 and according to the same evaluation rank as in Example 1.

  When applying the surface layer forming coating solution using an ultrasonic atomizer and setting the distance between the jet port and the surface of the substrate to 50 mm of the present invention, the viscosity of the surface layer forming coating solution is from 2 mPa · s to 50 mPa · s. It was confirmed that any of them exhibited excellent performance in film thickness stability, surface roughness stability, and durability. The effectiveness of the present invention was confirmed.

Example 4
An intermediate transfer belt having the substrate / surface layer structure shown in FIG. 2A was produced by the method described below.

(Production of endless belt-like substrate)
The same endless belt-like substrate as in Example 1 was produced.

(Formation of surface layer)
(Preparation of coating solution for surface layer formation)
The same surface layer forming coating solution as that used in Example 1 was prepared in the same manner as in Example 1.

(Application of coating solution for surface layer formation)
Using an ultrasonic atomizer (manufactured by Tick Corporation) as the coating apparatus shown in FIG. 3 on the surface of the prepared endless belt-shaped substrate, the distance from the jet port of the coating liquid discharge nozzle to the surface of the substrate is 250 mm, The prepared coating solution for forming a surface layer was applied by the following application method, and then the surface layer was applied so that the dry film thickness was 5 μm. The drying and heat treatment conditions at this time were as follows: after application, rotating at room temperature for 5 minutes, and then heat treating at 120 ° C. for 60 minutes to produce an intermediate transfer belt. 401 to 419.

(Application method)
The coating method for the surface layer forming coating solution is as follows. When the surface layer forming coating solution is applied on the surface of the endless belt-like substrate with an ultrasonic atomizer at a coating width of 80 mm, the endless belt-like substrate is shown in Table 4. Then, the coating was performed five times according to the flow shown in FIG. 5 while moving the ultrasonic atomizer in the direction orthogonal to the endless belt-like substrate. Other conditions were the same as in Example 1. Note that the length of movement of the ultrasonic atomizer indicates% relative to the coating width of the ultrasonic atomizer per second.

Evaluation The produced sample No. Table 5 shows the results of evaluation in the same manner as in Example 1 with respect to film thickness stability, surface roughness stability, and durability of 401 to 419, and evaluation according to the same evaluation rank as in the examples.

  When the surface layer forming coating solution is applied onto the surface of the endless belt-shaped substrate, the movement of the ultrasonic atomizer is temporarily stopped, the endless belt-shaped substrate is rotated and moved from 600 mm / min to 2000 mm / min, and Applying an ultrasonic atomizer per second while moving a length corresponding to 50% to 90% of the application width by the ultrasonic atomizer in a direction perpendicular to the rotational conveyance direction of the endless belt-like substrate. Sample No. applied by repeated application method It was confirmed that 402 to 406, 409 to 412, and 415 to 419 all showed excellent performance in film thickness stability, surface roughness stability, and durability. The effectiveness of the present invention was confirmed.

Example 5
An intermediate transfer belt having the substrate / surface layer structure shown in FIG. 2A was produced by the method described below.

(Production of endless belt-like substrate)
The same endless belt-like substrate as in Example 1 was produced.

(Formation of surface layer)
(Preparation of coating solution for surface layer formation)
The same surface layer forming coating solution as that used in Example 1 was prepared in the same manner as in Example 1.

(Application of coating solution for surface layer formation)
When the prepared coating solution for forming the surface layer was applied on the prepared endless belt-like substrate, sample No. 1 in Example 1 was used except that the coating width was changed as shown in Table 6. No. 103 was applied under the same application conditions as in the preparation of the intermediate transfer belt, and sample No. 501 to 508. The application width of the ultrasonic atomizer was changed by changing the distance from the jet port of the ultrasonic atomizer to the surface of the substrate.

Evaluation The produced sample No. Table 6 shows the results of evaluation according to the same evaluation rank as in Example 1 and evaluation according to the same evaluation rank as in Example 1 with respect to film thickness stability, surface roughness stability, and durability of 501 to 508.

  When using an ultrasonic atomizer and applying a coating solution for forming a surface layer, if the application width of the ultrasonic atomizer is 5 mm to 200 mm, all have excellent film thickness stability, surface roughness stability, and durability. It was confirmed that The effectiveness of the present invention was confirmed.

Example 6
An intermediate transfer belt having the substrate / surface layer structure shown in FIG. 2A was produced by the method described below.

(Production of endless belt-like substrate)
The same endless belt-like substrate as in Example 1 was produced.

(Formation of surface layer)
(Preparation of coating solution for surface layer formation)
The same surface layer forming coating solution as that used in Example 1 was prepared in the same manner as in Example 1.

(Application of coating solution for surface layer formation)
When applying the prepared coating solution for forming the surface layer on the prepared endless belt-like substrate, sample No. 1 in Example 1 of Example 1 was applied except that the coating amount was changed as shown in Table 9. No. 103 was applied under the same application conditions as in the preparation of the intermediate transfer belt, and sample No. 601 to 608. The spray amount of the sonic atomizer was changed by changing the pumping amount.

Evaluation The produced sample No. Table 7 shows the results of evaluation according to the same evaluation rank as that of Example 1 with respect to film thickness stability, surface roughness stability, and durability of 601 to 608 and evaluation according to the same evaluation rank as that of Example 1.

  When applying the coating solution for forming the surface layer using the ultrasonic atomizer and setting the distance between the jet outlet and the surface of the substrate to 50 mm according to the present invention, the spray amount of the ultrasonic atomizer is 2 ml / min to 350 ml / min. It was confirmed that all showed excellent performance in film thickness stability, surface roughness stability, and durability. The effectiveness of the present invention was confirmed.

DESCRIPTION OF SYMBOLS 1 Full-color image forming apparatus 10Y, 10M, 10C, 10K Image forming unit 1Y, 1M, 1C, 1K Photoconductor 4Y1, 4M1, 4C1, 4K1 Developing roller 4Y1a, 4Y'1a, 10 Conductive substrate 4Y1a1 First resin layer 4Y1a2 First 2 resin layer 4Y1a3, 4Y′1d surface layer 4Y′1b elastic layer 4Y′1c resin layer 6A, 6Y, 6M, 6C, 6K cleaning means 7 endless belt-like intermediate transfer body forming units 70, 70a to 70d intermediate transfer belt 701 substrate 702 Surface layer 703 Intermediate layer 703a First intermediate layer 703b Second intermediate layer 704 Elastic layer 9 Manufacturing process 9a Holding part 9b Application part 9b1 Ultrasonic atomizer 9b11 Application liquid supply pipe 9b2 Drive part

Claims (6)

In a method for producing an intermediate transfer belt having a surface layer for primary transfer of a toner image formed on the surface of an electrophotographic photosensitive member on the surface of an endless belt-like substrate,
An ultrasonic atomizer is used as the surface layer forming coating solution for forming the surface layer, and the distance between the ultrasonic atomizer and the surface of the belt-shaped substrate is 20 mm to 300 mm, and the surface layer forming coating solution is formed in the belt shape. A method for producing an intermediate transfer belt, comprising applying to a surface of a substrate.   2. The method for producing an intermediate transfer belt according to claim 1, wherein a solid content concentration of the surface layer forming coating solution is 5% by mass to 30% by mass.   The method for producing an intermediate transfer belt according to claim 1, wherein the coating liquid for forming the surface layer has a viscosity of 2 mPa · s to 50 mPa · s.   When applying the coating solution for forming the surface layer onto the surface of the endless belt-like substrate, the ultrasonic atomizer is applied per second while rotating the endless belt-like substrate at a speed of 600 mm / min to 2000 mm / min. 2. The coating according to claim 1, wherein a length corresponding to 50% to 90% of the coating width by the ultrasonic atomizer is applied while moving in a direction perpendicular to the rotational conveyance direction of the endless belt-like substrate. 4. The method for producing an intermediate transfer belt according to any one of items 1 to 3.   5. The method of manufacturing an intermediate transfer belt according to claim 1, wherein a coating width of the ultrasonic atomizer is 5 mm to 200 mm.   6. The method of manufacturing an intermediate transfer belt according to claim 1, wherein a spray amount of the coating liquid for forming the surface layer of the ultrasonic atomizer is 2 ml / min to 350 ml / min.

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