JP2011070004A - Cylindrical member for image forming apparatus and method of manufacturing the same, device for stretching the cylindrical member, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylindrical member for an image forming apparatus for preventing white spot and toner scattering, in an obtained image. <P>SOLUTION: The cylindrical member for the image forming apparatus contains at least a polyamide-imide resin and an electrical conductive material. The ratio (N/G) of surface resistivity (N) is 1.0 to 1.2 on the inner peripheral side to the surface resistivity (G) on the outer peripheral side. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a cylindrical member for an image forming apparatus, a method for manufacturing a cylindrical member for an image forming apparatus, a cylindrical member stretching apparatus, and an image forming apparatus.

An image forming apparatus using an electrostatic copying system forms a charge on an image carrier made of a photoconductive photosensitive member, forms an electrostatic latent image with a laser beam or the like that modulates an image signal, and then charges toner. The electrostatic latent image is developed into a visualized toner image.
For example, an image forming apparatus is disclosed in which an image is obtained by electrostatically transferring the toner image via an intermediate transfer member (see, for example, Patent Document 1).

  As an intermediate transfer member material used in an image forming apparatus employing the intermediate transfer member method, a material using a polyamideimide resin has been proposed. For example, endless cylindrical semiconductivity using an aromatic polyamideimide whose surface resistivity on the inner peripheral surface side is in the range of 0.1 to 0.9 times the surface resistivity on the outer peripheral surface side A polyamideimide film has been proposed (see, for example, Patent Document 2).

JP-A-62-206567 Japanese Patent No. 3218199

  An object of the present invention is to provide a cylindrical member that suppresses white spots and toner scattering in an obtained image as compared with a case where the ratio (N / G) is less than 1.0 or exceeds 1.2.

The above object is achieved by the present invention described below.
That is, the invention according to claim 1
Containing at least a polyamide-imide resin and a conductive material,
A cylindrical member for an image forming apparatus in which the ratio (N / G) of the surface resistivity (N) on the inner peripheral surface side to the surface resistivity (G) on the outer peripheral surface side is 1.0 or more and 1.2 or less. is there.

The invention according to claim 2
2. The cylindrical member for an image forming apparatus according to claim 1, wherein the thickness of the conductive material region on the outer peripheral surface side is 1.5 μm or more and 3 μm or less.

The invention according to claim 3
An application step of applying a resin composition containing at least a polyamideimide resin, a conductive material, and a solvent to the outer peripheral surface side of the core material at a temperature of 15 ° C. or higher and 35 ° C. or lower to form a coating film;
A drying step of drying the coating film to obtain a dry film, and heating the step-by-step heating in two or more stages, and the heating temperature in the first stage depends on the resin composition. A heating step in which the temperature of the heating in the last stage is lower than the peak temperature seen in the calorimetric change measurement using suggested thermal scanning thermal analysis of the main solvent contained, and higher than the peak temperature;
The manufacturing method of the cylindrical member for image forming apparatuses which has these.

The invention according to claim 4
A cylindrical member for an image forming apparatus according to claim 1 or 2,
A plurality of stretching members that rotatably stretch the cylindrical member from the inner peripheral surface side;
It is a cylindrical member stretching apparatus provided with.

The invention according to claim 5
An image carrier,
A charging device for charging the surface of the image carrier;
A latent image forming device that forms an electrostatic latent image on the image carrier charged by the charging device;
A developing device for developing the electrostatic latent image on the image carrier with toner to form a toner image;
A cylindrical member for intermediate transfer using the cylindrical member for an image forming apparatus according to claim 1 or 2,
A primary transfer device for transferring the toner image on the image carrier to the intermediate transfer cylindrical member;
A secondary transfer device for transferring the toner image transferred to the intermediate transfer cylindrical member to a recording medium;
An image forming apparatus.

Claim 6
The invention according to
An image carrier,
A charging device for charging the surface of the image carrier;
A latent image forming device that forms an electrostatic latent image on the image carrier charged by the charging device;
A developing device for developing the electrostatic latent image on the image carrier with toner to form a toner image;
A cylindrical member for conveying a recording medium using the cylindrical member for an image forming apparatus according to claim 1 or 2,
A transfer device for transferring the toner image on the image carrier to a recording medium conveyed by the cylindrical member for conveying the recording medium;
An image forming apparatus.

  According to the first aspect of the present invention, white spots and toner scattering in the obtained image are suppressed as compared with the case where the ratio (N / G) is less than 1.0 or exceeds 1.2.

  According to the second aspect of the present invention, white spots and toner scattering in the obtained image are suppressed as compared with the case where the thickness of the conductive material region is less than 1.5 μm or more than 3 μm.

  According to the third aspect of the present invention, compared to the case where the heating temperature at the first stage in the heating process is equal to or higher than the peak temperature found in the calorie change measurement of the main solvent, white spots and toner scattering are obtained in the obtained image. A suppressed cylindrical member is easily manufactured.

  According to the invention of claim 4, white spots and toner scattering in the obtained image are suppressed as compared with a case where a cylindrical member having a ratio (N / G) of less than 1.0 or more than 1.2 is not provided. The

  According to the invention of claim 5, an image in which white spots and toner scattering are suppressed is formed as compared with a case where a cylindrical member having a ratio (N / G) of less than 1.0 or more than 1.2 is not provided. Is done.

  According to the invention of claim 6, an image in which white spots and toner scattering are suppressed is formed as compared with a case where a cylindrical member having a ratio (N / G) of less than 1.0 or more than 1.2 is not provided. Is done.

It is the cross-sectional image of the whole film | membrane of the cylindrical member which concerns on this embodiment image | photographed with the microscope, the enlarged image of the interface of an inner peripheral surface side, and the enlarged image of the interface of an outer peripheral surface side. 1 is a schematic cross-sectional view illustrating an example of an image forming apparatus according to an embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

<Cylindrical member>
The cylindrical member for an image forming apparatus according to the present embodiment contains at least a polyamideimide resin and a conductive material, and has a surface resistivity (G) on the outer peripheral surface side of a surface resistivity (N) on the inner peripheral surface side. The ratio (N / G) to is 1.0 or more and 1.2 or less.

When a cylindrical member in which the ratio (N / G) of the surface resistivity (N) on the inner peripheral surface side to the surface resistivity (G) on the outer peripheral surface side is less than 1.0 is applied to the image forming apparatus, the inner periphery Since the surface resistivity on the surface side is low, current flows in addition to the nip region (for example, the region where the photosensitive member as the image holding member and the cylindrical member are in contact), and the resulting image has toner scattering and lines. Image quality defects such as omissions occur. On the other hand, when the ratio (N / G) exceeds 1.2, since the surface resistivity on the inner peripheral surface side is high, no current flows through the nip region, and the resulting image has poor image quality due to white spots or discharge. Occurs.
On the other hand, by using the cylindrical member according to this embodiment in which the ratio (N / G) is 1.0 or more and 1.2 or less, white spots and toner scattering in the obtained image are suppressed.

Here, the above “conductive material region” means that a coating layer coated with a polyamideimide resin, a conductive material and a resin composition containing a solvent is dried and further heated, whereby a solvent is formed on the outer peripheral surface. Refers to a region formed by evaporation of a conductive material such as carbon black that does not dissolve in the solvent and precipitates on the outer peripheral surface side. That is, it represents a region where the conductive material is deposited on the outer peripheral surface side and the conductive material is present at a high concentration.
FIG. 1 shows a cross-sectional image of the entire film of the cylindrical member according to the present embodiment taken with a microscope, an enlarged image of the interface on the inner peripheral surface side, and an enlarged image of the interface on the outer peripheral surface side. As shown in FIG. 1, it is confirmed that a conductive material region in which a conductive material is deposited is formed at the interface on the outer peripheral surface side.

-How to achieve-
The present inventors have found that the adjustment of the ratio (N / G) can be achieved by controlling the thickness of the conductive material region formed on the outer peripheral surface side of the cylindrical member. Also, the thickness of the conductive material region can be achieved by dividing the heating process (firing process) into two or more stages, increasing the temperature in stages, and controlling the heating temperature in the first stage. I found.
Specifically, the heating temperature in the first stage is heated at a temperature lower than the peak volatilization temperature of the main solvent (solvent (mass ratio) most contained as a solvent) contained in the resin composition. As a result, the drying on the surface on the outer peripheral surface side is delayed, so that the conductive material is deposited and the conductive material region is thickened. As a result, the surface resistivity on the outer peripheral surface side is increased. Thereby, the said ratio (N / G) is adjusted to 1.0 or more and 1.2 or less.
Conventionally, in the heating process (baking process), it has been common knowledge to set the heating temperature higher than the peak temperature in order to efficiently evaporate the solvent.

  Further, the adjustment of the ratio (N / G) is not limited to the control of the temperature in the first stage of the heating process described above, the selection of the type of conductive material added to the cylindrical member, and the addition amount of the conductive material It is also done by.

-Measurement method-
-Calorie change Measurement of the peak temperature seen in the calorie change measurement using the suggested thermal scanning thermal analysis of the main solvent (solvent (mass ratio) most contained as a solvent) contained in the resin composition is a thermal analyzer. Analysis is carried out by heating the polyamideimide varnish at a rate of 10 ° C./min using (Shimadzu Corporation DSC60).

-Thickness of conductive material region After the cylindrical member is embedded in the resin in advance, the cylindrical member is cut out together with the resin embedded in the microtome. After attaching a conductive double-sided tape to the cut section of the sample, an electrostatically removed sample is prepared. Conducting AFM measurement (Digital Instruments III, Nanoscope IIIa + D3100) is performed in the air at a resolution of 512 × 512 in the atmosphere while applying a measurement voltage of −4.0 V to the surface of the sample. At this time, a point flowing 0.7 pA or more between the probe and the conductive double-sided tape is defined as a conductive location, the distance from the surface of this conductive location is measured, and the average value is defined as the thickness of the conductive material region.

・ Surface resistivity The surface resistivity (and volume resistivity described later) of the cylindrical member is 22 ° C. and 55% RH in an environment of a double cylindrical probe (Hirester UP, manufactured by Dia Instruments Co., Ltd.) Probe "). The measurement conditions are a load of 2.0 kg, an applied voltage of 100 V to the inner cylinder of the apparatus, and a charge time of 10 seconds. The surface resistivity is calculated from the amount of current flowing between the inner cylinder (outer diameter 16 mm) and the outer cylinder (inner diameter 30 mm) on the insulating plate using the probe. On the other hand, the volume resistivity is measured according to JIS-K6911 (1995) using the probe.
The numerical values described in this specification are measured by the above method.

-Composition of cylindrical member-
Next, the composition of the cylindrical member according to this embodiment will be described.

(1) Polyamideimide resin The polyamideimide resin is a resin having an imide group and an amide group in the molecule, and one having a generally known structure is used. As a method for synthesizing a polyamideimide resin, an acid chloride method, an isocyanate method, or the like is known, and any of them is used. The isocyanate method is particularly desirable.
The isocyanate method is a method of reacting a carboxylic anhydride compound and a diisocyanate compound, and the acid chloride method is a method of reacting a carboxylic acid chloride compound and a diamine compound. Hereinafter, the carboxylic anhydride compound and the carboxylic chloride compound may be referred to as “carboxylic acid component”.

  As the carboxylic anhydride compound, trimellitic anhydride or a derivative thereof is desirable. In addition to the trimellitic anhydride or derivatives thereof, a carboxylic anhydride compound that reacts with an isocyanate group or amino group (for example, dicarboxylic anhydride, tetracarboxylic anhydride, etc.) may be used in combination.

The diisocyanate compound is a compound represented by the following general formula (1).
O = C = N-R-N = C = O General formula (1)
(In general formula (1), R represents a divalent aromatic group or an aliphatic group.)

  Specific examples of the diisocyanate compound include the following compounds. These diisocyanate compounds may be used alone or in combination of two or more compounds.

  Examples of the carboxylic acid chloride compound include trimellitic acid chloride or its derivative chloride. In addition to trimellitic acid chloride or its derivative chloride, dicarboxylic acid chloride, tetracarboxylic acid chloride, etc. may be used, or two or more of these may be used in combination.

  Examples of the diamine compound include aliphatic diamines such as ethylene diamine, propylene diamine, and hexamethylene diamine, alicyclic groups such as 1,4-cyclohexane diamine, 1,3-cyclohexane diamine, isophorone diamine, and 4,4′-diaminodicyclohexyl methane. Diamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, benzidine, o-tolidine, 2,4-tolylenediamine Aromatic diamines such as 2,6-tolylenediamine and xylylenediamine, among which 4,4′-diaminodiphenylmethane, isophoronediamine, 4,4′-diaminodicyclohexylmethane and the like are desirable.

  The blending ratio of the isocyanate compound or diamine compound and the carboxylic acid component is such that the ratio of the total mole number of isocyanate groups or amino groups to the total mole number of carboxyl groups and acid anhydride groups of the acid component is 0.6 or more and 1. It is desirable to be 4 or less, more desirably 0.7 or more and 1.3 or less, and particularly desirably 0.8 or more and 1.2 or less.

  Specific examples of the method for producing the polyamideimide resin by the isocyanate method include the following methods.

1) A method in which an isocyanate component and a tricarboxylic acid component are used at a time and reacted to obtain a polyamideimide resin.
2) A method in which an excess amount of an isocyanate component is reacted with an acid component to synthesize an amideimide oligomer having an isocyanate group at a terminal, and then a tricarboxylic acid component is added and reacted to obtain a polyamideimide resin.
3) After reacting an excess amount of a tricarboxylic acid component with an isocyanate component to synthesize an amideimide oligomer having a carboxylic acid or an acid anhydride group at the terminal, the acid component and the isocyanate component are added and reacted to obtain a polyamideimide resin. Method.

  In the method for producing the polyamide-imide resin, both the amidation reaction and the imidation reaction may be performed, or the imidization reaction may be performed after the amidation reaction is completed.

  The number average molecular weight of the polyamideimide resin thus obtained is preferably 20,000 or more and 50,000 or less, and more preferably 30,000 or more and 40,000 or less.

(2) Conductive material The conductive material represents a material that can impart conductivity to the cylindrical member according to the present embodiment, that is, the surface resistivity of the inner and outer peripheral surfaces of the cylindrical member is 10 ^13. The following refers to materials that can be controlled.
Examples of the conductive material include carbon black or a conductive polymer material.

As said carbon black, common carbon black, such as oil furnace black, channel black, acetylene black, is used. More specifically, Mitsubishi Chemical # 3350B, # 30, # 3030B, Tokai Carbon # 5500, Electrochemical Co., Ltd. granular acetylene black, Asahi Carbon Co., Ltd. HS-500, Asahi Thermal FT, Asahi Thermal MT, Ketchen Black from Lion Aguso, Vulcan XC-72 from Cabot, "REGAL 400R", "MONARCH 1300" from Cabot, "Color Black FW200" from "Degussa", " SPECIAL BLACK 4 ”,“ PRINTEX150T ”,“ PRINTEX140T ”,“ PRINTEX U ”, and the like.
Among these, it is desirable to use channel black or oxidized carbon black. Carbon black may be blended in a plurality instead of one.

  Examples of the conductive polymer material include polyaniline, polypyrrole, polythiophene, and polyacetylene. The conductive materials may be used alone or in combination.

  The addition amount of the conductive material used in the present embodiment is desirably 10 parts by mass or more and 50 parts by mass or less, and more desirably 15 parts by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the total solid content of the resin composition. .

  The conductive material can be dispersed in the polyamide-imide resin by a media mill that uses the impact force of the media such as ceramic beads and balls, or when a high shear force is applied through a small orifice at high pressure and collides. A commonly used dispersion method such as a wet jet mill or a homogenizer that uses the impact force of the above is used.

(3) Other additives In addition to the above, the cylindrical member according to the present embodiment includes an antioxidant for preventing thermal deterioration of the resin, a surfactant for improving fluidity, and the like. Any additive used as a cylindrical member of the image forming apparatus may be used.

-Manufacturing method of cylindrical member-
Next, the manufacturing method of the cylindrical member which concerns on this embodiment is demonstrated.
In the method for producing a cylindrical member according to this embodiment, a resin composition containing at least a polyamideimide resin, a conductive material, and a solvent is applied to the outer peripheral surface side of the core material at a temperature of 15 ° C. or more and 35 ° C. or less. The coating process for forming the coating film, the drying process for drying the coating film to obtain a dried film, and the dried film are heated by heating in stages in two or more stages. The heating temperature is lower than the peak temperature found in the calorimetric change measurement using the suggested thermal scanning thermal analysis of the main solvent contained in the resin composition, and the heating temperature in the last stage is lower than the peak temperature. And a high heating step, and further includes a peeling step for peeling the formed cylindrical member from the core material.

(A) Application process First, in the application process, a resin composition (polyamideimide resin solution) containing at least a polyamideimide resin, a conductive material and a solvent is prepared.
As the resin composition, a solution in which a polyamideimide resin is dissolved in an aprotic polar solvent is prepared. As the polyamide-imide resin, the various combinations listed above are used. The polyamideimide resin may be copolymerized during preparation of a resin composition or formation of a coating film by mixing a polyamideimide resin precursor in which an acid and an amine are mixed, and an acid and an amine or isocyanate. Moreover, you may mix and use 2 or more types of polyamideimide resins.

  Examples of the aprotic polar solvent include n-methyl-2-pyrrolidone, dimethylacetamide, diglyme and the like.

  Polyamideimide resin is prepared as a resin composition by dissolving in the above-mentioned solvent. In addition, the selection of the mixing ratio, concentration, viscosity, and the like of the polyamideimide precursor or polyamideimide resin in this preparation is adjusted and performed.

  Next, the resin composition is applied to the outer peripheral surface of the core material. The coating is desirably performed at a temperature of 15 ° C. or more and 35 ° C. or less, and more desirably performed at a temperature of 20 ° C. or more and 30 ° C. or less.

  As the core material, aluminum or stainless steel is preferably used, and stainless steel is particularly preferable. Moreover, in order to peel off the formed cylindrical member from the core material surface satisfactorily, the surface of the core material may be provided with releasability. In order to impart releasability, it is effective to plate the core material surface with chromium or nickel, coat the surface with a fluorine resin or silicone resin, or apply a release agent to the surface.

  As a method for applying the resin composition to the surface of the core material, for example, the resin composition is applied to the outer peripheral surface of the core material by moving the rotating core material in the rotation axis direction while discharging the resin composition from the nozzle. Examples thereof include a coating method and a dip coating method in which a core material is dipped in a resin composition and pulled up.

(B) Drying process In the manufacturing method of the cylindrical member according to this embodiment, a drying process for drying the formed coating film is performed after the coating process. The drying step is a step in which heating is performed for the purpose of losing the fluidity of the coating film of the resin composition applied to the core material surface.
The coating film made of the resin composition formed on the surface of the core material as described above is heated while rotating the core material to evaporate the solvent, and dried to a state where the solution does not flow without rotation, A dry film is formed. The amount of residual solvent in the dry film is desirably 50% by mass or less, and more desirably 40% by mass or less, based on the total mass of the dry film.
The drying condition in the drying step is a temperature lower than the peak temperature found in the calorimetric change measurement using the suggested thermal scanning thermal analysis of the main solvent contained in the resin composition, and 80 ° C. or more. It is desirable that the temperature is in the range of 180 ° C. or lower for 10 minutes or longer and 60 minutes or shorter, and more preferable that the temperature is in the range of 120 ° C. or higher and 150 ° C. or lower for 15 minutes or longer and 30 minutes or shorter.

(C) Heating process In the manufacturing method of the cylindrical member which concerns on this embodiment, the heating process (baking process) which heats the formed dry film at a still higher temperature is performed after the said drying process.
By heating at a higher temperature, the solvent is further volatilized in the dry film made of polyamideimide resin, and imide conversion is caused to form a resin film containing the polyamideimide resin.

In the method of manufacturing a cylindrical member according to the present embodiment, the heating process (firing process) is divided into two or more stages and heated in stages, and the heating temperature in the first stage is It is lower than the peak temperature seen in the calorimetric change measurement using the suggested thermal scanning thermal analysis of the main solvent contained in the resin composition, and the heating temperature in the last stage may be set higher than the peak temperature. desirable. By manufacturing the cylindrical member by the method, the thickness of the conductive material region is adjusted to the above-described range.
Note that “heating in steps” is a step in which heating is performed while maintaining the temperature for a predetermined time after reaching the required temperature by raising the temperature. Represents applying.

Here, for example, a method of heating in four steps will be described as an example. In addition, the resin composition to be used shall contain the main solvent whose said peak temperature is 150 degreeC. First, the temperature of the first stage is raised to 130 ° C. and held for 20 minutes, then the temperature of the second stage is raised to 175 ° C. and held for 20 minutes, and then the temperature of the third stage is raised to 220 ° C. The temperature is maintained for 20 minutes, and finally, the temperature is raised to a fourth stage temperature of 250 ° C. and maintained for 20 minutes, the solvent is removed, and the heating step is performed. As described above, it is desirable to perform the heating step by heating in steps and heating.
In addition, the heating temperature here refers to the preset temperature of the heating device, and refers to the preset temperature of the heating furnace, for example, when heating is performed by a heating furnace.

  Moreover, as a heating condition of the heating step, it is desirable that the temperature in at least one of the steps of raising the temperature divided into two or more steps is higher than the glass transition temperature (Tg) of the polyamide-imide resin. It is more desirable to heat at a temperature higher by 10 ° C or more and 50 ° C or less.

  The total heating time in the above heating step (the time from the start of the temperature increase in the first stage to the time of finishing the heating in the last stage) is preferably 20 minutes to 120 minutes, preferably 40 minutes. More preferably, it is 90 minutes or less.

  In addition, in the cylindrical member according to the present embodiment, after performing the coating step, the drying step, and the heating step, the coating step, the drying step, and the heating step are performed once or plural times using resin compositions having different compositions. It is good also as a cylindrical member which repeated and performed several layers.

(D) Peeling step The cylindrical member thus obtained is subjected to a peeling step in which the cylindrical member is peeled off by a known method such as blowing air into the gap between the core member and the cylindrical member. A cylindrical member is manufactured.
The thickness of the cylindrical member is preferably 0.05 mm or more and 0.2 mm or less, and more preferably 0.06 mm or more and 0.12 mm or less.

  In addition, the manufacturing method of the cylindrical member which concerns on this embodiment is not limited to the said method, You may form by the other well-known method.

-Physical properties of cylindrical members-
The surface resistivity of the cylindrical member according to the present embodiment, both the inner circumferential surface side and the outer peripheral surface side, it is desirably 1 × 10 ⁸ Ω / □ or more 1 × 10 ¹³ Ω / □ or less, 1 × 10 ⁹ It is more desirable that it is Ω / □ or more and 1 × 10 ¹² Ω / □ or less.

Further, the volume resistivity of the cylindrical member according to the present embodiment is preferably 10 ⁷ Ω · cm to 10 ¹² Ω · cm, and more preferably 10 ⁸ Ω · cm to 10 ¹¹ Ω · cm.

  The cylindrical member according to the present embodiment desirably has little variation in surface resistivity. As the variation width of the surface resistivity, the logarithmic value of a value obtained by dividing the maximum value of the surface resistivity in the cylindrical member by the minimum value is preferably within 1.0, more preferably within 0.6. Desirably, it is more desirable to be within 0.3.

  The cylindrical member according to the present embodiment may be in the form of a belt, or may be in the form of a drum in which the surface of the cylindrical base is coated with the belt-like cylindrical member.

<Image forming apparatus>
The cylindrical member according to the present embodiment is preferably used as a cylindrical member for an electrophotographic image forming apparatus, and particularly preferably used as an intermediate transfer cylindrical member or a recording medium conveyance cylindrical member. In other words, the following two aspects can be cited as desirable aspects of the image forming apparatus to which the cylindrical member according to the present embodiment is applied.

An image carrier, a charging device for charging the surface of the image carrier, a latent image forming device for forming an electrostatic latent image on the image carrier charged by the charging device, and the image carrier A developing device that develops an electrostatic latent image with toner to form a toner image, a cylindrical member for intermediate transfer using the cylindrical member according to the present embodiment, and the toner image on the image carrier as the intermediate A primary transfer device for transferring to a transfer cylindrical member; a secondary transfer device for transferring the toner image transferred to the intermediate transfer cylindrical member to a recording medium; and a fixing for fixing the toner image on the recording medium. An image forming apparatus.
When a cylindrical member is used as the intermediate transfer cylindrical member, the cylindrical member preferably has a surface resistivity of 1 × 10 ⁸ Ω / □ or more and 1 × 10 ¹² Ω / □ or less. .

An image carrier, a charging device for charging the surface of the image carrier, a latent image forming device for forming an electrostatic latent image on the image carrier charged by the charging device, and the image carrier A developing device that develops an electrostatic latent image with toner to form a toner image, a recording medium conveyance cylindrical member using the cylindrical member according to the present embodiment, and the toner image on the image holding member An image forming apparatus comprising: a transfer device that transfers to a recording medium conveyed by a recording medium conveying cylindrical member; and a fixing device that fixes a toner image on the recording medium.
When a cylindrical member is used as a recording medium conveying cylindrical member, the cylindrical member may have a surface resistivity of 1 × 10 ⁹ Ω / □ or more and 1 × 10 ¹² Ω / □ or less. desirable.

  In the following, an embodiment in which the cylindrical member according to the present embodiment is used as an intermediate transfer cylindrical member (intermediate transfer belt) will be described with reference to the drawings.

  FIG. 2 is a schematic diagram illustrating an example (one embodiment) of the configuration of the image forming apparatus according to the present embodiment. The image forming apparatus 100 according to the present embodiment is a so-called tandem system, and sequentially around the four image holding bodies 101a to 101d made of an electrophotographic photosensitive member along the rotation direction thereof, charging devices 102a to 102d, and exposure. Devices 114a to 114d, developing devices 103a to 103d, primary transfer devices (primary transfer rolls) 105a to 105d, and image carrier cleaning devices 104a to 104d are arranged. Note that a static eliminator may be provided in order to remove residual potential remaining on the surfaces of the image carriers 101a to 101d after transfer.

  Further, the intermediate transfer belt 107 is stretched around the stretching rolls 106a to 106d, the driving roll 111, and the opposing roll 108 to form a cylindrical member stretching device (belt stretching device) 107b. By these stretching rolls 106a to 106d, the driving roll 111, and the opposing roll 108, the intermediate transfer belt 107 is in contact with the surfaces of the image holding bodies 101a to 101d and the image holding bodies 101a to 101d and the primary transfer rolls 105a to 105a. 105d can be moved in the direction of arrow A. A portion where the primary transfer rolls 105a to 105d are in contact with the image carriers 101a to 101d via the intermediate transfer belt 107 is a primary transfer portion, and a contact portion between the image carriers 101a to 101d and the primary transfer rollers 105a to 105d is a primary transfer portion. A transfer voltage is applied.

  Further, as a secondary transfer device, a counter roll 108 and a secondary transfer roll 109 are arranged to face each other via an intermediate transfer belt 107 and a secondary transfer belt 116. The recording medium 115 such as paper moves in the direction of the arrow B while being in contact with the surface of the intermediate transfer belt 107 while being in contact with the surface of the intermediate transfer belt 107, and then passes through the fixing device 110. A portion where the secondary transfer roll 109 comes into contact with the opposing roll 108 via the intermediate transfer belt 107 and the secondary transfer belt 116 is a secondary transfer portion, and the secondary transfer roll 109 and the opposing roll 108 are in contact with the secondary transfer portion. A transfer voltage is applied. Further, intermediate transfer belt cleaning devices 112 and 113 are arranged so as to come into contact with the intermediate transfer belt 107 after transfer.

  In the multi-color image forming apparatus 100 having this configuration, the image carrier 101a rotates in the direction of the arrow C, and after the surface is charged by the charging device 102a, the first color static light is exposed by the exposure device 114a such as laser light. An electrostatic latent image is formed. The formed electrostatic latent image is developed (visualized) with toner by a developing device 103a containing toner corresponding to the color to form a toner image. The developing devices 103a to 103d contain toners (for example, yellow, magenta, cyan, and black) corresponding to the electrostatic latent images of the respective colors.

  The toner image formed on the image carrier 101a is electrostatically transferred (primary transfer) onto the intermediate transfer belt 107 by the primary transfer roll 105a when passing through the primary transfer portion. Thereafter, the toner images of the second color, the third color, and the fourth color are primarily transferred onto the intermediate transfer belt 107 holding the toner image of the first color by the primary transfer rollers 105b to 105d so that the toner images of the second color, the third color, and the fourth color are sequentially superimposed. Finally, a multi-colored multiple toner image is obtained.

  The multiple toner images formed on the intermediate transfer belt 107 are electrostatically collectively transferred to the recording medium 115 when passing through the secondary transfer portion. The recording medium 115 onto which the toner image has been transferred is conveyed to the fixing device 110, subjected to fixing processing by heating and / or pressurization, and then discharged outside the apparatus.

  The residual toner is removed from the image carriers 101a to 101d after the primary transfer by the image carrier cleaning devices 104a to 104d. On the other hand, residual toner is removed from the intermediate transfer belt 107 after the secondary transfer by the intermediate transfer belt cleaning devices 112 and 113 to prepare for the next image forming process.

(Image carrier)
As the image carriers 101a to 101d, known electrophotographic photoreceptors are widely applied. As the electrophotographic photoreceptor, an inorganic photoreceptor having a photosensitive layer made of an inorganic material, an organic photoreceptor having a photosensitive layer made of an organic material, or the like is used. In organic photoconductors, a function-separated type organic photoconductor that stacks a charge generation layer that generates charge upon exposure and a charge transport layer that transports charge, or a single layer that performs the function of generating charge and the function of transporting charge Type organic photoreceptors are preferably used. In addition, as the inorganic photoconductor, a photoconductive layer composed of amorphous silicon is preferably used.

  The shape of the image carrier is not particularly limited, and a known shape such as a cylindrical drum shape, a sheet shape, or a plate shape is employed.

[Charging device]
The charging devices 102a to 102d are not particularly limited, and are, for example, conductive (here, “conductive” in the charging device means, for example, a volume resistivity of less than 10 ⁷ Ω · cm) or semiconductive. (Here, “semiconductive” in the charging device means, for example, a volume resistivity of 10 ^{7 to} 10 ¹³ Ωcm.) A contact-type charger or corona using a roller, brush, film, rubber blade or the like Known chargers such as scorotron chargers and corotron chargers using discharge are widely applied. Among these, a contact charger is preferable.

  The charging devices 102a to 102d normally apply a direct current to the image carriers 101a to 101d, but an alternating current may be applied in a superimposed manner.

[Exposure equipment]
The exposure devices 114a to 114d are not particularly limited. For example, a light source such as a semiconductor laser light, an LED (Light Emitting Diode) light, or a liquid crystal shutter light is provided on the surface of the image carriers 101a to 101d, or these. A well-known exposure apparatus such as an optical system apparatus capable of performing imagewise exposure from a light source via a polygon mirror is widely applied.

[Development equipment]
The developing devices 103a to 103d are selected according to the purpose. For example, a known developing device that develops a one-component developer or a two-component developer in contact or non-contact with a brush or roller or the like can be used.

  The toner (developer) used in the image forming apparatus 100 of the present embodiment is not particularly limited, and includes, for example, a binder resin and a colorant.

  Examples of the binder resin include homopolymers and copolymers such as styrenes, monoolefins, vinyl esters, α-methylene aliphatic monocarboxylic acid esters, vinyl ethers, or vinyl ketones. Examples of the binder resin include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, Examples thereof include polyethylene and polypropylene. Furthermore, polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin wax, and the like can be given.

  Coloring agents include magnetic powders such as magnetite and ferrite, carbon black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, and lamp black. Rose Bengal, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 57: 1, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 17, C.I. I. Pigment blue 15: 1 or C.I. I. Pigment Blue 15: 3 is a typical example.

  The toner may be internally added or externally added with known additives such as a charge control agent, a release agent, and other inorganic particles.

  Typical examples of the release agent include low molecular polyethylene, low molecular polypropylene, Fischer-Tropsch wax, montan wax, carnauba wax, rice wax, and candelilla wax.

  As the charge control agent, known ones are used, and azo metal complex compounds, metal complex compounds of salicylic acid, or resin type charge control agents containing polar groups are used.

As other inorganic particles, small-diameter inorganic particles having an average primary particle size of 40 nm or less are used for the purpose of powder flowability, charge control, etc., and for reducing adhesion, inorganic or organic particles having a larger diameter than that are used. Particles may be used in combination. As these other inorganic particles, known ones are used.
In addition, the surface treatment of the small-diameter inorganic particles is effective because the dispersibility becomes high and the effect of increasing the powder fluidity increases.

  As a method for producing the toner, a polymerization method such as an emulsion polymerization aggregation method or a dissolution suspension method is preferably used because high shape controllability can be obtained. In addition, a manufacturing method may be performed in which the toner obtained by these methods is used as a core, and agglomerated particles are further adhered and heat-fused to have a core-shell structure.

  In addition, when adding an external additive, it can manufacture by mixing a toner and an external additive with a Henschel mixer or a V blender. In addition, when the toner is manufactured by a wet method, it may be externally added by a wet method.

[Primary transfer roll]
The primary transfer rolls 105a to 105d may be either a single layer or a multilayer. For example, in the case of a single layer structure, it is composed of a roll in which an appropriate amount of conductive particles such as carbon black is blended in foamed or non-foamed silicone rubber, urethane rubber, EPDM, or the like.

[Image carrier cleaning device]
The image carrier cleaning devices 104a to 104d are for removing residual toner adhering to the surfaces of the image carriers 101a to 101d after the primary transfer process. In addition to the cleaning blade, brush cleaning or roll cleaning is performed. Used. Among these, it is desirable to use a cleaning blade. Examples of the material for the cleaning blade include urethane rubber, neoprene rubber, and silicone rubber.

[Secondary transfer roll]
The layer structure of the secondary transfer roll 109 is not particularly limited. For example, in the case of a three-layer structure, the secondary transfer roll 109 includes a core layer, an intermediate layer, and a coating layer covering the surface. The core layer is a foamed material such as silicone rubber, urethane rubber, or EPDM in which conductive particles are dispersed, and the intermediate layer is composed of these non-foamed materials. Examples of the material for the coating layer include tetrafluoroethylene-hexafluoropropylene copolymer or perfluoroalkoxy resin. The volume resistivity of the secondary transfer roll 109 is desirably 10 ⁷ Ωcm or less. Moreover, it is good also as a two-layer structure except an intermediate | middle layer.

[Opposite roll]
The counter roll 108 forms a counter electrode of the secondary transfer roll 109. The layer structure of the facing roll 108 may be either a single layer or a multilayer. For example, in the case of a single layer structure, it is composed of a roll in which an appropriate amount of conductive particles such as carbon black is blended in silicone rubber, urethane rubber, EPDM, or the like. In the case of a two-layer structure, it is composed of a roll in which the outer peripheral surface of the elastic layer made of the rubber material is covered with a high resistance layer.

  A voltage of 1 kV or more and 6 kV or less is normally applied to the opposed roll 108 and the shaft of the secondary transfer roll 109. Instead of applying a voltage to the shaft of the opposing roll 108, a voltage may be applied to the electrically conductive electrode member brought into contact with the opposing roll 108 and the secondary transfer roll 109. Examples of the electrode member include a metal roll, a conductive rubber roll, a conductive brush, a metal plate, or a conductive resin plate.

[Fixing device]
As the fixing device 110, for example, a known fixing device such as a heat roller fixing device, a pressure roller fixing device, or a flash fixing device is widely applied.

[Intermediate transfer belt cleaning device]
As the intermediate transfer belt cleaning devices 112 and 113, brush cleaning, roll cleaning, or the like is used in addition to the cleaning blade. Among these, it is desirable to use the cleaning blade. Examples of the material for the cleaning blade include urethane rubber, neoprene rubber, and silicone rubber.

  In the above-described embodiments, a so-called tandem image forming apparatus including a plurality of image carriers has been described. However, the intermediate transfer belt is rotated and imaged by the number of colors of one image carrier. The image forming apparatus may be a so-called multi-cycle method (for example, a 4-cycle method).

  EXAMPLES Examples and comparative examples will be described below, but the present invention is not limited to the following examples. In the following, “parts” and “%” represent mass standards unless otherwise specified.

[Example 1]
50 phr of carbon black (FW1, Degussa, primary particle size 13 nm) is added to solvent-soluble polyamideimide resin (HPC-9000, manufactured by Hitachi Chemical Co., Ltd., solid content: 18%, solvent: n-methyl-2-pyrrolidone). Then, using a high-pressure collision type disperser (manufactured by Genus), dispersion was performed 5 times by passing through an orifice having a diameter of 0.1 mm at 200 MPa and colliding the slurry divided into two. A high-viscosity polyamideimide varnish was added to this with stirring so that the blending mass of carbon black was 20 parts with respect to 100 parts as a whole, to obtain a coating liquid (A).
When the change in calorific value of the coating solution (A) was measured by the above-described method, the peak temperature of the calorific value was 150 ° C.

This coating solution (A) was applied to the outer peripheral surface of an aluminum pipe having a diameter of 278 by dip coating (application process), and was subjected to rotary drying at 120 ° C. for 20 minutes (drying process). In contrast, in a furnace in which the first stage temperature is 130 ° C. for 20 minutes, the second stage temperature is 175 ° C. for 20 minutes, the third stage temperature is 220 ° C. for 20 minutes, and the fourth stage temperature is 250 ° C. for 20 minutes. The solvent was removed (heating process) to form a resin film (A). The resin film (A) was extracted (peeling step), and a cylindrical member was obtained by setting it to a predetermined width.
The thickness of this cylindrical member was 82 μm.

[Example 2]
50 phr of carbon black (FW1, Degussa, primary particle size 13 nm) is added to solvent-soluble polyamideimide resin (HPC-9000, manufactured by Hitachi Chemical Co., Ltd., solid content 18%, solvent is n-methyl-2-pyrrolidone). Then, using a high-pressure collision type disperser (manufactured by Genus), dispersion was performed 5 times by passing through an orifice having a diameter of 0.1 mm at 200 MPa and colliding the slurry divided into two. A high-viscosity polyamideimide varnish was added to this while stirring so that the blending mass of carbon black was 19.5 parts with respect to 100 parts as a whole, to obtain a coating liquid (B).
When the calorie | heat amount change of this coating liquid (B) was measured by the above-mentioned method, the peak temperature of calorie | heat amount was 150 degreeC.

  This coating solution (B) was applied to the outer peripheral surface of an aluminum pipe having a diameter of 278 by dip coating (application process), and was subjected to rotary drying at 120 ° C. for 20 minutes (drying process). In contrast, in a furnace in which the first stage temperature is 130 ° C. for 20 minutes, the second stage temperature is 175 ° C. for 20 minutes, the third stage temperature is 220 ° C. for 20 minutes, and the fourth stage temperature is 250 ° C. for 20 minutes. Solvent removal was performed (heating step) to form a resin film (B).

Further, on the resin film (B), using the coating liquid (A) shown in Example 1, a coating process / drying process / heating process is performed in the same manner as the formation of the resin film (B). The resin film (A) was laminated on (B). The laminated resin film was extracted (peeling step), and a cylindrical member was obtained by setting the resin film to a predetermined width.
The thickness of the resin film (B) of this cylindrical member was 10 μm, the film thickness of the resin film (A) was 71 μm, and the total film thickness was 81 μm.

Example 3
50 phr of carbon black (FW1, Degussa, primary particle size 13 nm) is added to solvent-soluble polyamideimide resin (HPC-9000, manufactured by Hitachi Chemical Co., Ltd., solid content 18%, solvent is n-methyl-2-pyrrolidone). Then, using a high-pressure collision type disperser (manufactured by Genus), dispersion was performed 5 times by passing through an orifice having a diameter of 0.1 mm at 200 MPa and colliding the slurry divided into two. A high-viscosity polyamideimide varnish was added to this with stirring so that the blending mass of carbon black was 20.2 parts with respect to 100 parts as a whole, to obtain a coating liquid (C).
When the change in calorie of this coating liquid (C) was measured by the above-mentioned method, the peak temperature of the calorie was 150 ° C.

  This coating liquid (C) was applied to the outer peripheral surface of an aluminum pipe having a diameter of 278 by dip coating (application process), and was subjected to rotary drying at 120 ° C. for 20 minutes (drying process). In contrast, in a furnace in which the first stage temperature is 130 ° C. for 20 minutes, the second stage temperature is 175 ° C. for 20 minutes, the third stage temperature is 220 ° C. for 20 minutes, and the fourth stage temperature is 250 ° C. for 20 minutes. The solvent was removed (heating step) to form a resin film (C).

Further, on the resin film (C), using the coating liquid (A) shown in Example 1, a coating process / drying process / heating process is performed in the same manner as in the formation of the resin film (C). The resin film (A) was laminated on (C). The laminated resin film was extracted (peeling step), and a cylindrical member was obtained by setting the resin film to a predetermined width.
The thickness of the resin film (C) of this cylindrical member was 10 μm, the film thickness of the resin film (A) was 71 μm, and the total film thickness was 81 μm.

[Comparative Example 1]
50 phr of carbon black (FW1, Degussa, primary particle size 13 nm) is added to solvent-soluble polyamideimide resin (HPC-9000, manufactured by Hitachi Chemical Co., Ltd., solid content 18%, solvent is n-methyl-2-pyrrolidone). Then, using a high-pressure collision type disperser (manufactured by Genus), dispersion was performed 5 times by passing through an orifice having a diameter of 0.1 mm at 200 MPa and colliding the slurry divided into two. A high-viscosity polyamideimide varnish was added to this while stirring so that the blending mass of carbon black was 19 parts with respect to 100 parts as a whole, and a coating solution (D) was obtained.
When the change in the amount of heat of the coating solution (D) was measured by the above-described method, the peak temperature of the amount of heat was 150 ° C.

  This coating solution (D) was applied to the outer peripheral surface of an aluminum pipe having a diameter of 278 by dip coating (application process), and was subjected to rotary drying at 120 ° C. for 20 minutes (drying process). In contrast, in a furnace in which the first stage temperature is 130 ° C. for 20 minutes, the second stage temperature is 175 ° C. for 20 minutes, the third stage temperature is 220 ° C. for 20 minutes, and the fourth stage temperature is 250 ° C. for 20 minutes. The solvent was removed (heating step) to form a resin film (D).

Further, on the resin film (D), using the coating liquid (A) shown in Example 1, a coating process / drying process / heating process is performed in the same manner as in the formation of the resin film (D). The resin film (A) was laminated on (D). The laminated resin film was extracted (peeling step), and a cylindrical member was obtained by setting the resin film to a predetermined width.
The thickness of the resin film (D) of this cylindrical member was 10 μm, the film thickness of the resin film (A) was 70 μm, and the total film thickness was 80 μm.

[Comparative Example 2]
50 phr of carbon black (FW1, Degussa, primary particle size 13 nm) is added to solvent-soluble polyamideimide resin (HPC-9000, manufactured by Hitachi Chemical Co., Ltd., solid content 18%, solvent is n-methyl-2-pyrrolidone). Then, using a high-pressure collision type disperser (manufactured by Genus), dispersion was performed 5 times by passing through an orifice having a diameter of 0.1 mm at 200 MPa and colliding the slurry divided into two. A high-viscosity polyamideimide varnish was added to this with stirring so that the blending mass of carbon black was 20.5 parts with respect to 100 parts as a whole, to obtain a coating liquid (E).
When the change in the calorific value of this coating liquid (E) was measured by the above-described method, the peak temperature of the calorific value was 150 ° C.

  This coating solution (E) was applied to the outer peripheral surface of an aluminum pipe having a diameter of 278 by dip coating (application process), and was subjected to rotary drying at 120 ° C. for 20 minutes (drying process). In contrast, in a furnace in which the first stage temperature is 130 ° C. for 20 minutes, the second stage temperature is 175 ° C. for 20 minutes, the third stage temperature is 220 ° C. for 20 minutes, and the fourth stage temperature is 250 ° C. for 20 minutes. The solvent was removed (heating step) to form a resin film (E).

Further, on the resin film (E), using the coating liquid (A) shown in Example 1, a coating process / drying process / heating process is performed in the same manner as in the formation of the resin film (E). The resin film (A) was laminated on (E). The laminated resin film was extracted (peeling step), and a cylindrical member was obtained by setting the resin film to a predetermined width.
The thickness of the resin film (E) of this cylindrical member was 9 μm, the film thickness of the resin film (A) was 72 μm, and the total film thickness was 81 μm.

Example 4
In the heating process of Example 1, a cylindrical member was obtained in the same manner as in Example 1 except that the first stage temperature was 115 ° C. for 20 minutes. The thickness of this cylindrical member was 80 μm.

Example 5
In the heating process of Example 1, a cylindrical member was obtained in the same manner as in Example 1 except that the first stage temperature was 145 ° C. for 20 minutes. The thickness of this cylindrical member was 81 μm.

[Comparative Example 3]
In the heating process of Example 1, a cylindrical member was obtained in the same manner as in Example 1 except that the first stage temperature was 155 ° C. for 20 minutes. The thickness of this cylindrical member was 81 μm.

[Comparative Example 4]
A cylindrical member was obtained in the same manner as in Example 1 except that in the heating process of Example 1, the first stage temperature was 110 ° C. for 20 minutes and the second stage temperature was 210 ° C. for 20 minutes. The thickness of this cylindrical member was 81 μm.

Example 6
50 phr of carbon black (FW1, manufactured by Degussa, primary particle size 13 nm) is added to solvent-soluble polyamideimide resin (HPC-9000, manufactured by Hitachi Chemical Co., Ltd., solid content: 18%, solvent: dimethylacetamide), and high-pressure collision dispersion Dispersion was performed 5 times using a machine (manufactured by Genus), passing through an orifice of φ0.1 mm at 200 MPa and colliding the slurry divided into two. A high-viscosity polyamideimide varnish was added to this with stirring so that the blending mass of carbon black was 20 parts with respect to 100 parts as a whole, and a coating solution (F) was obtained.
When the change in calorific value of the coating solution (F) was measured by the above-described method, the peak temperature of the calorific value was 130 ° C.

This coating solution (F) was applied to the outer peripheral surface of an aluminum pipe having a diameter of 278 by dip coating (application process), and was subjected to rotary drying at 110 ° C. for 20 minutes (drying process). In contrast, in a furnace in which the first stage temperature is 120 ° C. for 20 minutes, the second stage temperature is 175 ° C. for 20 minutes, the third stage temperature is 220 ° C. for 20 minutes, and the fourth stage temperature is 250 ° C. for 20 minutes. The solvent was removed (heating step) to form a resin film (F). The resin film (F) was extracted (peeling process), and the cylindrical member was obtained by making it into the defined width.
The thickness of this cylindrical member was 82 μm.

-Image quality evaluation-
The cylindrical members obtained in the above examples and comparative examples are mounted as an intermediate transfer belt of DocuPrint C2250 manufactured by Fuji Xerox Co., Ltd., and are half-tone (30% magenta) on A3 vertical paper in a low temperature and low humidity environment of 22 ° C. and 55% RH ) Image was transferred. The secondary transfer voltage at this time was 5.6 kV. The obtained halftone image was visually judged as “white spot / toner scattered image” based on the following evaluation criteria.
◎: No white spots / no toner splatters ○: Slight white spots / toner splatters △: White spots / toner splatters ×: Severe white spots / toner splatters

101a to 101d Image holders 102a to 102d Charging devices 103a to 103d Developing devices 104a to 104d Image carrier cleaning devices 105a to 105d Primary transfer rolls 106a to 106d Tension roll 107 Intermediate transfer belt 107b Cylindrical member tension device (belt tension) Mounting device)
108 Counter roll 109 Secondary transfer roll 110 Fixing device 111 Drive roll 112 Intermediate transfer belt cleaning blade 113 Intermediate transfer belt cleaning brushes 114a to 114d Image exposure device 115 Recording medium 116 Secondary transfer belt

Claims (6)

Containing at least a polyamide-imide resin and a conductive material,
A cylindrical member for an image forming apparatus, wherein the ratio (N / G) of the surface resistivity (N) on the inner peripheral surface side to the surface resistivity (G) on the outer peripheral surface side is 1.0 or more and 1.2 or less.   The cylindrical member for an image forming apparatus according to claim 1, wherein the thickness of the conductive material region on the outer peripheral surface side is 1.5 μm or more and 3 μm or less. An application step of applying a resin composition containing at least a polyamideimide resin, a conductive material, and a solvent to the outer peripheral surface side of the core material at a temperature of 15 ° C. or higher and 35 ° C. or lower to form a coating film;
A drying step of drying the coating film to obtain a dry film, and heating the step-by-step heating in two or more stages, and the heating temperature in the first stage depends on the resin composition. A heating step in which the temperature of the heating in the last stage is lower than the peak temperature seen in the calorimetric change measurement using suggested thermal scanning thermal analysis of the main solvent contained, and higher than the peak temperature;
A method for manufacturing a cylindrical member for an image forming apparatus. A cylindrical member for an image forming apparatus according to claim 1 or 2,
A plurality of stretching members that rotatably stretch the cylindrical member from the inner peripheral surface side;
A cylindrical member stretching apparatus comprising: An image carrier,
A charging device for charging the surface of the image carrier;
A latent image forming device that forms an electrostatic latent image on the image carrier charged by the charging device;
A developing device for developing the electrostatic latent image on the image carrier with toner to form a toner image;
A cylindrical member for intermediate transfer using the cylindrical member for an image forming apparatus according to claim 1 or 2,
A primary transfer device for transferring the toner image on the image carrier to the intermediate transfer cylindrical member;
A secondary transfer device for transferring the toner image transferred to the intermediate transfer cylindrical member to a recording medium;
An image forming apparatus comprising: An image carrier,
A charging device for charging the surface of the image carrier;
A latent image forming device that forms an electrostatic latent image on the image carrier charged by the charging device;
A developing device for developing the electrostatic latent image on the image carrier with toner to form a toner image;
A cylindrical member for conveying a recording medium using the cylindrical member for an image forming apparatus according to claim 1 or 2,
A transfer device for transferring the toner image on the image carrier to a recording medium conveyed by the cylindrical member for conveying the recording medium;
An image forming apparatus comprising: