JP2018091941A - Endless belt, intermediate transfer belt, image forming apparatus, and image forming method - Google Patents

Abstract

An endless belt having electrical characteristics, mechanical characteristics, cleaning properties, durability, and transferability is provided. An endless belt comprising polyether ether ketone and a filler, wherein the filler contains carbon and a metal oxide, and the voltage dependency of surface resistivity at 100 V to 500 V is 2 digits or less. [Selection figure] None

Description

  The present invention relates to an endless belt, an intermediate transfer belt, an image forming apparatus, and an image forming method.

Conventionally, an endless belt has been used as a means for conveying an object. An example of the endless belt is an intermediate transfer member used in an electrophotographic image forming apparatus.
The intermediate transfer member is required to have uniformity of electric resistance, surface smoothness, mechanical properties (high bending, high elasticity, high elongation), and high dimensional accuracy (film thickness, circumference). Further, the intermediate transfer member is laid out over a wide area of the image forming apparatus, and is required to be flame retardant because a high voltage is applied for transfer. UL94 standard VTM- 1st is a must.

  As a material that can satisfy these required characteristics, an intermediate transfer member using a flame-retardant thermoplastic resin has been proposed. For example, an intermediate transfer member (for example, see Patent Document 1) containing polyether ether ketone, which is a kind of flame retardant thermoplastic resin, and a conductive filler has been proposed. In addition to the above proposals, an intermediate transfer member in which a conductive filler is unevenly distributed in a polymer alloy (see, for example, Patent Document 2), an intermediate transfer member containing a thermoplastic crystalline resin, and the like (for example, Patent Document 3). reference).

  An object of the present invention is to provide an endless belt that has electrical characteristics, mechanical characteristics, cleaning properties, durability, and transferability.

The endless belt of the present invention as means for solving the above-mentioned problems is
Including polyetheretherketone and filler,
The filler comprises carbon and a metal oxide;
The voltage dependency of the surface resistivity at 100V to 500V is 2 digits or less.

  According to the present invention, an endless belt having electrical characteristics, mechanical characteristics, cleaning properties, durability, and transferability can be provided.

FIG. 1 is a schematic diagram of a main part showing an example of an image forming apparatus of the present invention. FIG. 2 is a schematic diagram of a main part showing another example of the image forming apparatus of the present invention.

(Endless belt)
The endless belt of the present invention includes polyether ether ketone (hereinafter also referred to as “polyether ether ketone resin”, “PEEK”, “PEEK resin”) and a filler, and further includes other components as necessary.

  Conventionally, a heat-resistant endless belt containing a polyimide resin has been proposed. As a technique for manufacturing the heat-resistant endless belt from the polyimide resin, for example, there are the following methods. This is a method of forming a polyimide endless belt by casting a polyimide varnish on the outer peripheral surface of a cylindrical body made of metal and then heating and imidizing the cast polyimide varnish. However, this technique has the problem that the material cost is high and the imidization process takes time and the production cost is also high. Furthermore, since a new mold is required every time the dimensional standard is changed, a large number of molds are required, and there is a problem that the initial cost is increased.

The intermediate transfer member is an expensive part of the electrophotographic apparatus, and cost reduction is strongly demanded. In order to reduce the cost, if a thermoplastic resin is used and it can be molded by extrusion molding or inflation molding, it can be manufactured at a very low cost.
Examples of the flame retardant thermoplastic resin include PPS (polyphenylene sulfide) resin, PVDF (polyvinylidene chloride) and other fluorine resins, polyarylate resin, PES (polyethersulfone) resin, PS (polysulfone) resin, and PEI (polyethylene sulfide). Etherimide) resin, PEEK (polyetheretherketone) resin, TPI (thermoplastic polyimide), LCP (liquid crystal polymer), PBT (polybutylene terephthalate), PEN (polyethylene naphthalate), TPE (thermoplastic elastomer), etc.・ Practical use.

In Japanese Patent No. 558740, a proposal is made to enable resistivity control in a medium resistance region, which has been difficult in the past, by making a conductive filler unevenly distributed in the dispersed phase in a polymer alloy. However, when the electrical characteristics are adjusted by the polymer alloy, it is easy to obtain the resistivity, but the following problems occur.
・ Resistance variation in the circumferential direction ・ Surface properties such as roughness and gloss are deteriorated ・ Local abnormal discharge that may be caused by non-uniform dispersion occurs. May worsen. Therefore, in order to obtain a function as a product, there remains a problem that it must be absorbed by a hard surface such as a toner and a blade and a soft surface such as a transfer electric field.
Accordingly, as a result of intensive studies by the present inventors, it has been found that an endless belt satisfying all of the following conditions has improved fine particle cleaning properties and transfer properties such as toner.
・ Use polyether ether ketone as resin ・ Use metal oxide and carbon as filler ・ Voltage dependence of surface resistivity at 100V to 500V is 2 digits or less

<Polyetheretherketone>
The polyether ether ketone is contained in order to improve the moldability of the endless belt and improve the mechanical properties.
As said polyetheretherketone, what was synthesize | combined suitably may be used and a commercial item may be used. When using the said commercial item, the reaction material, catalyst, residue, etc. which are previously contained in the raw material may exist.
Examples of the commercially available products include Vesta Keep L4000G (manufactured by Daicel-Evonik), 151G, 450PF (manufactured by Victrex), and the like. These may be used individually by 1 type and may use 2 or more types together.
As the PEEK, it is preferable to use two or more types of PEEK having different molecular weights. By using two or more types of PEEK having different molecular weights, it is easy to adjust the viscosity of the endless belt material when manufacturing the endless belt, and the formability and electrical characteristics of the endless belt are improved.

<Filler>
The filler includes carbon and a metal oxide. When the filler is only carbon, the voltage dependency, electrical characteristics such as resistance deviation, and transferability are deteriorated. When the filler is only a metal oxide, surface resistivity, durability, and transferability deteriorate.
Until now, an endless belt including a resin and a filler has been proposed. In many cases, the filler is a combination of conduction by carbon black and conduction by an ionic conductive material. A resin composition containing a filler in which the carbon black and the ionic conductive material are combined is also called a hybrid conductive resin composition. Generally, in an endless belt using the hybrid conductive resin composition, when the ratio of the addition amount of the ionic conductive agent to the addition amount of carbon black is increased, the voltage dependency is improved but the environmental dependency is deteriorated. It is known. On the other hand, it is known that when the ratio of the addition amount of the ionic conductive agent to the addition amount of carbon black is lowered, the voltage dependency is deteriorated but the environment dependency is improved. Therefore, the trade-off between voltage dependency and environment dependency cannot be avoided in principle. In addition to this, in consideration of characteristics such as resistivity variation and resistivity anisotropy (hereinafter referred to as “resistance deviation”), an endless belt having excellent electrical characteristics in all aspects is very It was hard to get. In the conventional endless belt, one of the electrical characteristics has to be compromised. In particular, the circumferential variation in resistance value is often the compromise.
For this reason, in the present invention, by using a metal oxide instead of an ionic conductive agent, voltage dependency, environment dependency, circumferential variation in resistance value, and resistivity anisotropy were solved. However, even if an ionic conductive agent is added, an ionic conductive agent can be used in combination as long as the effects of the present invention are not impaired.

<< Carbon >>
There is no restriction | limiting in particular as said carbon, According to the objective, it can select suitably, For example, acetylene black, carbon black, Ketjen black, nonelectroconductive carbon etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, carbon black is preferable.
The carbon black (sometimes referred to as “CB”) is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include carbon nanotubes, fullerenes, and graphite. These may be used individually by 1 type and may use 2 or more types together.

There is no restriction | limiting in particular as DBP oil absorption amount of the said carbon, Although it can select suitably according to the objective, 220g or more is preferable with respect to 100g of said carbon, and 300g or more is more preferable. Since the DBP oil absorption amount is 220 g or more with respect to 100 g of the carbon, the total amount of the filler added can be reduced, so that the mechanical strength and moldability can be improved.
The DBP oil absorption is measured by ASTM (American Standard Test Method) D-2414-6TT and indicates the amount of DBP (dibutyl phthalate) absorbed in 100 g of carbon. The DBP oil absorption can be measured as follows using a dibutyl phthalate absorber in accordance with the method defined in JIS K6217. Carbon as a measurement sample is put into a chamber of a measurement device (absorbometer), and DBP is added at a constant speed. As the DBP is absorbed, the viscosity of the carbon increases. The DBP oil absorption amount is calculated on the basis of the amount of DBP absorbed until the viscosity reaches a predetermined value. The viscosity is detected by a torque sensor.
The carbon may have a DBP oil absorption of 200 g or more per 100 g of carbon (hereinafter also referred to as “carbon having a high DBP oil absorption”), and the DBP oil absorption may be used per 100 g of carbon. Carbon less than 200 g (hereinafter also referred to as “carbon having a low DBP oil absorption”) may be used in combination.
The content of carbon having the low DBP oil absorption is preferably 36 parts by mass or less with respect to 100 parts by mass of the carbon having the high DBP oil absorption.

  As the carbon, those appropriately synthesized may be used, or commercially available products may be used. Examples of commercial products of carbon black having a high DBP oil absorption include EC600JD (Lion Specialty Chemicals Co., Ltd.), special black 4, Printex U (or Orion Co., Ltd.), and the like. These may be used individually by 1 type and may use 2 or more types together. Commercially available products of carbon black having a low DBP oil absorption include Denka Black (Electrochemical Industry Co., Ltd.), Toka Black (Tokai Carbon Co., Ltd.), VXC72R (Cabot Corp.), SB400, X15 (above, Asahi Carbon Co., Ltd.) 3400B (Mitsubishi Chemical Corporation).

<< Metal oxide >>
There is no restriction | limiting in particular as said metal oxide, According to the objective, it can select suitably, For example, zinc oxide, a tin oxide, aluminum oxide, vanadium oxide, a scandium oxide etc. are mentioned. In addition, the metal oxide may contain and dissolve nitrides and carbides, or may be a composite oxide containing two or more kinds of metals. The crystal structure of the metal oxide may be amorphous. It may be coated with metal oxide or coated with metal oxide. These may be used individually by 1 type and may use 2 or more types together. Among these, zinc oxide is preferable because the manufacturing cost can be suppressed.
When the metal oxide is used for an endless belt, the metal oxide crystal is often further doped with a metal that acts as an acceptor or donor for the purpose of obtaining conductivity. The metal used for doping may contain a non-conductive metal oxide. Examples of the metal used for the doping include B, Al, Ga, In, Tl, N, P, As, Sb, Bi, Sc, Y, Ti, Zr, and Hf.

  As said metal oxide, what was synthesize | combined suitably or a commercial item may be sufficient. Examples of the commercially available product include SP-2 (Mitsubishi Materials Electronics Chemical Co., Ltd.) and pazetCK (Hakusitek Co., Ltd.).

As content of the said filler, 18 mass parts-36 mass parts are preferable with respect to 100 mass parts of said PEEK, and 20 mass parts-30 mass parts are more preferable. When the content is 18 parts by mass to 36 parts by mass, the surface roughness can be made appropriate and the mechanical strength can be improved.
The content mass of the metal oxide is preferably equal to or greater than the content mass of the carbon. When the metal oxide content is greater than or equal to the carbon content, the electrical characteristics are improved.

<Other ingredients>
The other components are not particularly limited as long as the characteristics of the present invention are not impaired, and can be appropriately selected according to the purpose. For example, a lubricant such as silicone oil; a conductive agent such as metal; talc, carbon Non-conductive oxides such as nanotubes, silica and zirconia; polymer alloys other than the PEEK are included. These may be used individually by 1 type and may use 2 or more types together.
There is no restriction | limiting in particular as content of the said other component, unless the effect of this invention is impaired, It can select suitably according to the objective.

<Physical properties of endless belt>
The endless belt of the present invention preferably satisfies the following characteristics, mechanical characteristics, and electrical characteristics.

(1) Characteristics The differential scanning calorimetry (DSC) of the endless belt at 150 ° C. to 200 ° C. (hereinafter also referred to as “crystallization endothermic peak” or “ΔH”) is preferably less than 10 J / g. / G is more preferable, and it is still more preferable that a significant peak is not detected (0 J / g). When ΔH is in the numerical range, it is possible to prevent problems such as a large change in the surface property of the belt when the paper passing durability is performed and the belt breaking.
The ΔH can be adjusted by the ratio of PEEK crystals in the endless belt, the state of dispersion of the filler, the thermal history (how to apply heat) when manufacturing the endless belt, and the like.
The DSC is measured in an air atmosphere by measuring at 10 ° C./min using, for example, an Al pan using ThermoPlusEVO2 (manufactured by Rigaku Corporation). For TG measurement, use Pt pan and measure up to 990 ° C.

Japanese Patent No. 4799214 discloses a belt having a special crystallinity pattern. However, the belt tends to inevitably suffer from a problem of deterioration of cleaning property and rupture at a portion having a high crystallization endothermic peak (ΔH).
The ΔH of the endless belt of the present invention can be discussed as an average value of the crystallinity of the entire endless belt. However, belts with extremely varying ΔH are not preferable because the cleaning property tends to deteriorate or mechanically break at the low crystallinity points. If the variation in ΔH cannot be suppressed, there is no problem even if a reaction of about 10 J / g remains even if a contrivance such as lowering the crystallinity of a portion that is not important in terms of function such as an end portion is taken. In addition, as described above, ΔH is only an index used to indicate crystallinity. Therefore, if it corresponds to crystallinity, mechanical properties such as X-ray diffraction and tensile tests, specific gravity, density, etc. Discussions on properties such as hardness are possible as well. Also, ΔH is usually different in the depth direction of the film thickness. However, when ΔH on the cooling mechanism side is increased unintentionally, or ΔH in the depth direction is intentionally inclined or equalized. Even in such cases, it is important to discuss the overall average value.

  When analyzing the components contained in the endless belt in more detail, energy dispersive X-ray analysis (EDS) is used as elemental analysis. Examples of the EDS include equipment incidental to JEM2100M (manufactured by JEOL). Furthermore, analysis using X-ray diffraction (XRD), inductively coupled plasma (ICP), or the like may be used as necessary.

The gloss of the endless belt preferably has a glossiness of 10 to 150, and more preferably 50 to 100. The gloss value is related to the cleaning property. When the gloss value is high, the cleaning property is good. If the gloss value is 10 to 150, the following problems can be prevented.
・ Defects that reduce the cleaning performance of the image forming apparatus ・ Defects that the accuracy of the toner detection sensor decreases ・ Defects that cause the cleaning blade to turn up or make noise, etc. The phenomenon of turning over or making abnormal noise is likely to occur when the gloss value exceeds 150.
The gloss value can be adjusted by changing the amount of conductive agent filler added or the content of PEEK resin in the endless belt.
The gloss can be measured, for example, by measuring 20 ° gloss with a gloss meter (PG-1, manufactured by Nippon Denshoku Co., Ltd.). In addition, the said cleaning property refers to the property excellent in scraping off microparticles | fine-particles.

The endless belt may contain diphenyl sulfone. The diphenyl sulfone is a substance used in manufacturing PEEK.
The content of diphenyl sulfone in the endless belt is preferably 350 ppm or less, more preferably 250 ppm or less, 200 ppm or less, 150 ppm or less, 100 ppm or less, 50 ppm or less, and 30 ppm or less, and most preferably 5 ppm or less. When the content is 350 ppm or less, the following problems can be prevented.
・ Defects that cause deterioration in image quality such as abnormal discharge ・ Defects that generate gas during molding and deteriorate the quality of the molded product ・ Defects that increase the risk of bleed-out and deteriorate cleaning properties The content of diphenylsulfone is the same as the endless belt In the production of, the temperature and time during kneading, or the temperature and time during molding can be adjusted.
The content of the diphenyl sulfone can be measured by, for example, gas chromatography (G-3000, manufactured by Hitachi, Ltd.).

(2) Mechanical properties The folding endurance by the MIT test at the curvature R5.0 of the endless belt is preferably 1 million times or more, more preferably 1.2 million times or more, further preferably 1.5 million times or more, and 2 million times The above is particularly preferable.
The MIT test uses a value measured in an extrusion direction under a load of 500 g with a test piece having a width of 15 mm using MIT-DA (manufactured by Toyo Seiki Co., Ltd.).

The average thickness of the endless belt is preferably 40 μm to 250 μm, and more preferably 50 μm to 100 μm.
The average thickness of the endless belt can be determined, for example, by measuring the circumferential direction at a pitch of 10 mm using a Mitutoyo micrometer.

The surface roughness of the endless belt (hereinafter sometimes abbreviated as “Rz”) is preferably 0.2 μm to 1 μm, more preferably 0.2 μm to 0.7 μm, and more preferably 0.2 μm to 0.5 μm. More preferably, 0.2 μm to 0.4 μm is particularly preferable, and 0.3 μm to 0.4 μm is most preferable.
The surface roughness can be adjusted by, for example, polishing or coating. When the surface roughness is within the numerical range, the following problems can be prevented.
-Failure to scrape off fine particles (for example, toner) with a blade, etc.-Failure to vibrate or turn the blade under strong torque. The surface roughness is, for example, a laser microscope (LEXT OLS4100, manufactured by Olympus). ) Is used to perform 3D synthesis of the surface shape, and calculation is performed under the conditions of λc = 800 μm, λs = 2.5 μm, and λf = none.

(3) Electrical characteristics The voltage dependency of the surface resistivity at 100 V to 500 V of the endless belt (hereinafter abbreviated as “voltage dependency of surface resistivity”) is 2 digits or less, preferably 1 digit or less. . When the voltage dependency of the surface resistivity exceeds two digits, there arises a problem that transferability is lowered. This decrease in transferability is particularly likely to occur under a high transfer electric field. Note that when the endless belt is used as an intermediate transfer member in the image forming apparatus, a voltage of 500 V may be applied in the apparatus, and thus the voltage dependency of the surface resistivity is measured between 100 V and 500 V. .
Further, the difference between the common logarithm of the surface resistivity at an applied voltage of 100 V and the common logarithm of the surface resistivity at an applied voltage of 500 V is referred to as “voltage dependency of the surface resistivity at 100 V to 500 V”.
For example, if the surface resistivity (500 V) is 1 × 10 ¹¹ Ω / □, the surface resistivity (100 V) at that time is 1 × 10. ^It means that it is below ¹² Ω / □.

  The voltage dependency of the surface resistivity can be measured, for example, by the following method. First, the surface resistivity on the back side of the endless belt is measured using a URES probe of Hiresta UP MCP-HT450 (manufactured by Mitsubishi Chemical Analytech Co., Ltd.) after 100 V is applied for 10 seconds (surface resistance at 100 V). rate). Next, the surface resistivity of the back side of the endless belt is measured using a URS probe of Hiresta UP MCP-HT450 (manufactured by Mitsubishi Chemical Analytech Co., Ltd.) after 500 V and 10 s have been applied (at 500 V). Surface resistivity). The difference between the common logarithm value of the surface resistivity at 100V and the common logarithm value of the surface resistivity at 500V is calculated.

The surface resistivity of the endless belt when a voltage of 500 V is applied is preferably 1 × 10 ⁸ Ω / □ to 1 × 10 ¹³ Ω / □, more preferably 10 ⁹ Ω / □ to 10 ¹² Ω / □. More preferably, 10 ¹⁰ Ω / □ to 10 ¹¹ Ω / □. When the surface resistivity is in the numerical range, the following problems can be prevented.
-Insufficient transfer electric field to toner-Occurrence of abnormal discharge-Decrease in transferability or increase in abnormal image The surface resistivity of the endless belt refers to the surface resistivity of the back side.
The surface resistivity can be adjusted, for example, by polishing or coating.
The surface resistivity can be measured after applying 500 V and 10 s, for example, using a Hiresta UP MCP-HT450 type (manufactured by Mitsubishi Chemical Analytech Co., Ltd.) URS probe. As the number of measurement points, for example, about 20 to 60 points in the circumferential direction and 2 to 3 points in the axial direction are measured, and the average value or the difference between the maximum value and the minimum value is used as the value. However, the number of measurement points can be appropriately selected depending on how the resistance value varies. In addition, since the place once measured cannot be measured correctly for a while, it measures after taking time. The transferability refers to a property excellent in transferring fine particles to a medium.
The surface resistivity may drift over time after the endless belt is formed. In that case, it is preferable to finally make it fall within the numerical range, but there is no problem if only the surface resistivity immediately after molding is within the numerical range.

The surface resistivity of the endless belt usually refers to the value on the back side. The back side refers to the inside of the endless belt. When the endless belt is used in an image forming apparatus, the side on which no toner is applied is the back side.
As the surface resistivity of the endless belt, the value on the front side is preferably higher than the value on the back side, and more preferably the same.

The impedance of the endless belt at 1 V and 1 kHz is preferably 10 kΩ to 10 MΩ, and more preferably 100 kΩ to 1 MΩ. When the impedance satisfies the numerical range, the following problems can be prevented.
-Trouble that transfer property is lowered when transfer voltage is increased-Trouble that transfer property is lowered when transfer electric field is weak The impedance can be adjusted by, for example, polishing or coating.
The impedance can be measured using, for example, the following apparatuses and equipment. Measurement is performed at 1 V using IM3536 (manufactured by Hioki Electric Co., Ltd.) as a measuring device. At this time, the probe is L2000 and the electrode is a metal of φ30, and is used so as to be sandwiched in the film thickness direction.

  There is no restriction | limiting in particular as a shape of the endless belt of this invention, Although it can select suitably according to the objective, A seamless belt is preferable.

<Method for producing endless belt>
The manufacturing method of the endless belt of the present invention includes a melt-kneading step and an extrusion molding step, and further includes other steps as necessary.

In Japanese Patent No. 4563665, 5 to 40 parts by mass of a conductive filler is added to PEEK and melted, and the molten film is cooled by a cooling roll or a cooling mandrel controlled at a temperature of 60 to 120 ° C. It is disclosed to obtain a semiconductive film by solidifying or the like. However, in the present invention, when the degree of crystallinity of the film is low, there is a problem that the cleaning property and the life of the image quality are shortened.
In a system containing a specific conductive agent, it is preferable to cool the film in a molten state at the following cooling temperature or to promote crystallization without contacting anything. The cooling temperature is preferably 120 ° C. or higher, more preferably 140 ° C. or higher, still more preferably 160 ° C. or higher, particularly preferably 190 ° C. or higher, most preferably 220 ° C. or higher, and a cooling mechanism controlled at 250 ° C. ± 5 ° C. It is preferable to contact them. It has been found that the crystallization method not only makes it easy to balance mechanical and electrical properties, but also increases the durability with time of cleaning. However, this is not the case when there are a plurality of cooling mechanisms. For example, if the following two conditions are satisfied, a low-temperature cooling device such as 60 ° C. can be introduced.
・ The first cooling roll is 60 ° C, the second cooling roll is 200 ° C, and the third cooling roll is 60 ° C. ・ Low-speed molding conditions such that excessive ΔH is not detected. Can be changed with a certain width from the characteristics of the film required by the user and conditions such as the kind of filler, the amount added, and the film thickness. For this reason, it is necessary to search for the optimum ΔH and the range of molding conditions for realizing it each time, which is an important technique in itself. In the case of a general electrophotographic or transport seamless belt having a cleaning mechanism such as a roller and a blade, ΔH is 10 J / g or less, preferably 5 J / g or less, more preferably no significant peak is observed. It is preferable to adjust to. ΔH usually varies depending on the position of the belt. In this case, ΔH may be represented by an average value of ΔH of the entire belt. Even if ΔH of a part of the belt exceeds 10 J / g, there is no immediate problem.

<< Melt kneading process >>
The melt-kneading step is a step of obtaining a melt-kneaded product by melt-kneading the PEEK resin, the filler, the metal oxide, and the other components. As said melt-kneaded material, a pellet form is preferable.
The melt kneading step preferably uses a kneader. The kneader is not particularly limited as long as the purpose of mixing and dispersing the materials is not impaired, and can be appropriately selected according to the purpose. For example, uniaxial, biaxial, kneader, powder mixing, and manual stirring , Banbury and so on.
The temperature during the melt kneading is preferably 300 ° C to 400 ° C.

<< Extrusion process >>
The extrusion molding step is a step of extruding the melt-kneaded product, and is performed by an extrusion molding means.
In the extrusion molding step, the pellets are extruded using an annular die or the like, and an endless belt having a desired dimension can be manufactured.
As the extrusion molding means, it is usually the most efficient to extrude a seamless tubular film using an annular die, but a coating method such as T-die molding, injection molding, blow molding, roll coating, inflation, etc. Various molding methods such as molding may be applied.
Even if the molding temperature and the mold temperature are lower than the melting point of the material, there is no problem in obtaining the effect of the present invention.

  There is no restriction | limiting in particular as said other process, According to the objective, it can select suitably, For example, a cutting process, a washing | cleaning process, a drying process etc. are mentioned.

  The endless belt of the present invention can be used with high durability as a direct or intermediate transfer body or medium that can efficiently adsorb, desorb and convey objects electrically and mechanically. Therefore, it is suitable for use as a paper conveying belt or an intermediate transfer belt in at least an image forming apparatus typified by an electrophotographic apparatus.

(Image forming apparatus and image forming method)
The image forming apparatus of the present invention includes a developing unit, an intermediate transfer member, and a transfer unit, and further includes other units appropriately selected as necessary.
The developing means is means for developing a latent image formed on the image carrier to form a toner image.
The intermediate transfer member is a member that primarily transfers the toner image and secondarily transfers the toner image to a medium.
The transfer means is means for secondary transfer of the primary transferred toner image onto a medium.
The intermediate transfer member (also referred to as “intermediate transfer belt”) is composed of the endless belt of the present invention.
In this case, it is preferable that the image forming apparatus is a full-color image forming apparatus, in which a plurality of latent image carriers having developing units for respective colors are arranged in series.

The image forming method of the present invention includes a development step, a primary transfer step, and a secondary transfer step, and further includes other steps as necessary.
The developing step is a step of developing a latent image formed on the image carrier to form a toner image.
The primary transfer step is a step of transferring the toner image developed in the developing step onto an intermediate transfer member.
The secondary transfer step is a step of secondarily transferring the toner image primarily transferred onto the intermediate transfer member onto a medium.
The intermediate transfer member (also referred to as “intermediate transfer belt”) is composed of the endless belt of the present invention.

  An endless belt (hereinafter also referred to as a “seamless belt”) used in a belt component provided in the image forming apparatus will be described in detail below with reference to a schematic diagram of a main part. The schematic diagram is an example, and the present invention is not limited to this.

FIG. 1 is a schematic view of an essential part for explaining an image forming apparatus equipped with a seamless belt obtained by the manufacturing method according to the present invention as a belt member.
An intermediate transfer unit 500 including a belt member shown in FIG. 1 includes an intermediate transfer belt 501 that is an intermediate transfer member stretched around a plurality of rollers. Around the intermediate transfer belt 501 are a secondary transfer bias roller 605 that is a secondary transfer charge applying unit of the secondary transfer unit 600, a belt cleaning blade 504 that is an intermediate transfer member cleaning unit, and a lubricant for a lubricant application unit. A lubricant application brush 505 or the like that is an application member is disposed so as to face each other.

  Further, a position detection mark (not shown) is provided on the outer peripheral surface or the inner peripheral surface of the intermediate transfer belt 501. However, on the outer peripheral surface side of the intermediate transfer belt 501, it is necessary to devise a position detection mark that avoids the passing area of the belt cleaning blade 504, which may be difficult to arrange. A position detection mark may be provided on the inner peripheral surface side of the intermediate transfer belt 501. An optical sensor 514 serving as a mark detection sensor is provided at a position between the primary transfer bias roller 507 and the belt driving roller 508 where the intermediate transfer belt 501 is bridged.

  The intermediate transfer belt 501 is stretched around a primary transfer bias roller 507, a belt driving roller 508, a belt tension roller 509, a secondary transfer counter roller 510, a cleaning counter roller 511, and a feedback current detection roller 512, which are primary transfer charge applying units. It is built. Each roller is made of a conductive material, and each roller other than the primary transfer bias roller 507 is grounded. The primary transfer bias roller 507 is applied with a transfer bias controlled to a predetermined current or voltage in accordance with the number of superimposed toner images by a primary transfer power source 801 controlled by constant current or constant voltage. .

The intermediate transfer belt 501 is driven in the arrow direction by a belt driving roller 508 that is driven to rotate in the arrow direction by a drive motor (not shown).
The intermediate transfer belt 501 as a belt member is usually a semiconductor or an insulator and has a single layer or a multilayer structure. However, in the present invention, a seamless belt is preferably used, and this improves durability. Excellent image formation can be realized. Further, the intermediate transfer belt is set to be larger than the maximum sheet passing size in order to superimpose the toner images formed on the photosensitive drum 200.

  A secondary transfer bias roller 605 as a secondary transfer unit is connected to a belt outer peripheral surface of the intermediate transfer belt 501 stretched by the secondary transfer counter roller 510 by a contact / separation mechanism, which will be described later. It is configured to be able to contact and separate. The secondary transfer bias roller 605 is disposed so as to sandwich the transfer paper P, which is a recording medium, between a portion of the intermediate transfer belt 501 stretched around the secondary transfer counter roller 510 and a constant current. A transfer bias having a predetermined current is applied by a secondary transfer power source 802 to be controlled.

  The registration roller 610 feeds the transfer sheet P, which is a transfer material, between the secondary transfer bias roller 605 and the intermediate transfer belt 501 stretched around the secondary transfer counter roller 510 at a predetermined timing. Further, a cleaning blade 608 as a cleaning unit is in contact with the secondary transfer bias roller 605. The cleaning blade 608 is for removing the adhering matter adhering to the surface of the secondary transfer bias roller 605 for cleaning.

  In the color copying machine having such a configuration, when an image forming cycle is started, the photosensitive drum 200 is rotated in a counterclockwise direction indicated by an arrow by a drive motor (not shown), and Bk ( Black) toner image formation, C (cyan) toner image formation, M (magenta) toner image formation, and Y (yellow) toner image formation are performed. The intermediate transfer belt 501 is rotated clockwise by the belt driving roller 508 as indicated by an arrow. As the intermediate transfer belt 501 rotates, the primary transfer of the Bk toner image, the C toner image, the M toner image, and the Y toner image is performed by the transfer bias due to the voltage applied to the primary transfer bias roller 507. In addition, toner images are formed on the intermediate transfer belt 501 in the order of Bk, C, M, and Y.

For example, the Bk toner image formation is performed as follows.
In FIG. 1, a charging charger 203 uniformly charges the surface of the photosensitive drum 200 to a predetermined potential with a negative charge by corona discharge. The timing is determined based on the belt mark detection signal, and raster exposure using laser light is performed based on the Bk color image signal by a writing optical unit (not shown). When this raster image is exposed, the charge proportional to the exposure light amount disappears in the exposed portion of the surface of the photosensitive drum 200 that is initially uniformly charged, and a Bk electrostatic latent image is formed. When the negatively charged Bk toner on the developing roller of the Bk developing device 231K comes into contact with this Bk electrostatic latent image, the toner does not adhere to the remaining portion of the photosensitive drum 200, and the charge is not charged. The toner is attracted to the nonexposed portion, that is, the exposed portion, and a Bk toner image similar to the electrostatic latent image is formed.

  The Bk toner image formed on the photosensitive drum 200 in this manner is primarily transferred to the belt outer peripheral surface of the intermediate transfer belt 501 that is rotating at a constant speed while being in contact with the photosensitive drum 200. Some untransferred residual toner remaining on the surface of the photosensitive drum 200 after the primary transfer is cleaned by the photosensitive member cleaning device 201 in preparation for the reuse of the photosensitive drum 200. On the photosensitive drum 200 side, the process proceeds to the C image forming process after the Bk image forming process, and reading of the C image data by the color scanner starts at a predetermined timing. By writing the laser beam with the C image data, the photosensitive drum A C electrostatic latent image is formed on the surface of 200.

  Then, after the rear end portion of the previous Bk electrostatic latent image passes and before the front end portion of the C electrostatic latent image arrives, the revolver developing unit 230 is rotated, and the C developing machine 231C develops. The C electrostatic latent image is developed with C toner. Thereafter, the development of the C electrostatic latent image area is continued. When the rear end of the C electrostatic latent image passes, the revolver developing unit is rotated in the same manner as in the case of the previous Bk developing machine 231K, and the next The M developing machine 231M is moved to the developing position. This is also completed before the leading edge of the next Y electrostatic latent image reaches the developing position. Note that the M and Y image forming steps are the same as the Bk and C steps described above because the operations of reading color image data, forming an electrostatic latent image, and developing are the same as those described above.

The Bk, C, M, and Y toner images sequentially formed on the photosensitive drum 200 in this manner are sequentially aligned on the same surface on the intermediate transfer belt 501 and primarily transferred. As a result, a toner image having a maximum of four colors superimposed on the intermediate transfer belt 501 is formed. On the other hand, at the time when the image forming operation is started, the transfer paper P is fed from a paper feed unit such as a transfer paper cassette or a manual feed tray, and waits at the nip of the registration roller 610.
When the leading edge of the toner image on the intermediate transfer belt 501 reaches the secondary transfer portion where a nip is formed by the intermediate transfer belt 501 stretched around the secondary transfer counter roller 510 and the secondary transfer bias roller 605. Then, the registration roller 610 is driven so that the leading edge of the transfer paper P coincides with the leading edge of the toner image, and the transfer paper P is conveyed along the transfer paper guide plate 601, and the transfer paper P and the toner image are transferred. Resist alignment is performed.

  In this way, when the transfer paper P passes through the secondary transfer portion, the four-color superimposed toner image on the intermediate transfer belt 501 is transferred by the transfer bias applied by the secondary transfer power source 802 to the secondary transfer bias roller 605. Are collectively transferred (secondary transfer) onto the transfer paper P. After the transfer paper P is conveyed along the transfer paper guide plate 601 and passed through a portion facing the transfer paper neutralization charger 606 composed of a static elimination needle disposed on the downstream side of the secondary transfer portion, it is neutralized. Then, the toner is fed toward the fixing device 270 by the belt conveyance device 210 which is a belt component. Then, after the toner image is melted and fixed at the nip portions of the fixing rollers 271 and 272 of the fixing device 270, the transfer paper P is sent out of the apparatus main body by a discharge roller (not shown), and is stacked face up on a copy tray (not shown). Is done. Note that the fixing device 270 may be configured to include a belt component if necessary.

  On the other hand, the surface of the photosensitive drum 200 after the belt transfer is cleaned by the photosensitive member cleaning device 201 and is uniformly discharged by the discharging lamp 202. Further, residual toner remaining on the outer peripheral surface of the intermediate transfer belt 501 after the toner image is secondarily transferred to the transfer paper P is cleaned by the belt cleaning blade 504. The belt cleaning blade 504 is configured to be brought into contact with and separated from the belt outer peripheral surface of the intermediate transfer belt 501 at a predetermined timing by a cleaning member separating and contacting mechanism (not shown).

  On the upstream side of the belt cleaning blade 504 in the moving direction of the intermediate transfer belt 501, a toner seal member 502 is provided that contacts and separates from the outer peripheral surface of the intermediate transfer belt 501. The toner seal member 502 receives the falling toner that has dropped from the belt cleaning blade 504 during the cleaning of the residual toner, and prevents the falling toner from scattering on the transfer path of the transfer paper P. The toner seal member 502 is brought into contact with and separated from the belt outer peripheral surface of the intermediate transfer belt 501 together with the belt cleaning blade 504 by the cleaning member separating and contacting mechanism.

  The lubricant 506 scraped by the lubricant application brush 505 is applied to the outer peripheral surface of the intermediate transfer belt 501 from which the residual toner has been removed in this way. The lubricant 506 is made of, for example, a solid body such as zinc stearate, and is disposed so as to come into contact with the lubricant application brush 505. Further, the residual charge remaining on the outer peripheral surface of the intermediate transfer belt 501 is removed by a neutralizing bias applied by a belt neutralizing brush (not shown) that is in contact with the outer peripheral surface of the intermediate transfer belt 501. Here, the lubricant application brush 505 and the belt neutralizing brush are brought into contact with and separated from the belt outer peripheral surface of the intermediate transfer belt 501 at a predetermined timing by respective contact and separation mechanisms (not shown). .

  Here, at the time of repeat copy, the operation of the color scanner and the image formation on the photosensitive drum 200 are performed at a predetermined timing following the first color (Y) image formation process of the first sheet and the first color of the second sheet. The process proceeds to the image forming process (Bk). Further, the intermediate transfer belt 501 has a second Bk toner in the area cleaned by the belt cleaning blade 504 on the outer peripheral surface of the belt following the batch transfer process of the first four-color superimposed toner image to the transfer paper. Ensure that the image is primarily transferred. After that, the operation is the same as the first sheet. The above is a copy mode for obtaining a four-color full-color copy, but in the three-color copy mode and the two-color copy mode, the same operation as described above is performed for the designated color and number of times. In the case of the single color copy mode, only the predetermined color developing machine of the revolver developing unit 230 is set in the developing operation state until the predetermined number of sheets is completed, and the belt cleaning blade 504 is kept in contact with the intermediate transfer belt 501. The copy operation is performed in the state.

In the above-described embodiment, the copying machine having only one photosensitive drum has been described. However, the present invention can seamlessly include a plurality of photosensitive drums as shown in an example of the configuration in the schematic diagram of the main part in FIG. The present invention can also be applied to an image forming apparatus arranged side by side along one intermediate transfer belt made of a belt.
FIG. 2 shows a four-drum digital color printer including four photosensitive drums 21Bk, 21Y, 21M, and 21C for forming toner images of four different colors (black, yellow, magenta, and cyan). A configuration example is shown.

  In FIG. 2, the printer body 10 includes an image writing unit 12, an image forming unit 13, and a paper feeding unit 14 for performing color image formation by an electrophotographic method. Based on the image signal, the image processing unit converts the image signal into black (Bk), magenta (M), yellow (Y), and cyan (C) color signals for image formation. Send. The image writing unit 12 is a laser scanning optical system including, for example, a laser light source, a deflector such as a rotary polygon mirror, a scanning imaging optical system, and a mirror group. Image writing corresponding to each color signal is performed on image carriers (photoconductors) 21BK, 21M, 21Y, and 21C that have a writing optical path and are provided for each color of the image forming unit 13.

  The image forming unit 13 includes photoconductors 21Bk, 21M, 21Y, and 21C that are image carriers for black (Bk), magenta (M), yellow (Y), and cyan (C). As each photoconductor for each color, an OPC photoconductor is usually used. Around each of the photoreceptors 21Bk, 21M, 21Y, and 21C, there are a charging device, a laser beam exposure unit from the writing unit 12, and developing devices 20Bk, 20M, and 20Y for black, magenta, yellow, and cyan colors. 20C, primary transfer bias rollers 23Bk, 23M, 23Y, and 23C as primary transfer means, a cleaning device (not shown), a photoconductor neutralizing device (not shown), and the like. The developing devices 20Bk, 20M, 20Y, and 20C use a two-component magnetic brush developing system. The intermediate transfer belt 22, which is a belt component, is interposed between each photoconductor 21Bk, 21M, 21Y, 21C and each primary transfer bias roller 23Bk, 23M, 23Y, 23C, and is formed on each photoconductor. The toner images of each color are sequentially superimposed and transferred.

  On the other hand, the transfer paper P is fed from the paper feed unit 14 and then carried by the transfer conveyance belt 50, which is a belt component, via the registration roller 16. When the intermediate transfer belt 22 and the transfer conveyance belt 50 come into contact with each other, the toner image transferred onto the intermediate transfer belt 22 is subjected to secondary transfer (collective transfer) by a secondary transfer bias roller 60 as secondary transfer means. ) As a result, a color image is formed on the transfer paper P. The transfer paper P on which the color image is formed is conveyed to the fixing device 15 by the transfer conveying belt 50, and after the image transferred by the fixing device 15 is fixed, it is discharged out of the printer main body.

  Residual toner remaining on the intermediate transfer belt 22 without being transferred during the secondary transfer is removed from the intermediate transfer belt 22 by the belt cleaning member 25. A lubricant application device 27 is disposed on the downstream side of the belt cleaning member 25. The lubricant application device 27 includes a solid lubricant and a conductive brush that rubs the intermediate transfer belt 22 to apply the solid lubricant. The conductive brush is always in contact with the intermediate transfer belt 22 and applies a solid lubricant to the intermediate transfer belt 22. The solid lubricant has an effect of improving the cleaning property of the intermediate transfer belt 22, preventing the occurrence of filming, and improving the durability.

  Examples of the present invention will be described below, but the present invention is not limited to these examples. “Part” means “part by mass” unless otherwise specified.

Example 1
100 parts by mass of PEEK1 (Vesta Keep L4000G, manufactured by Daicel Evonik), 7 parts by mass of carbon black 1 (EC600JD, manufactured by Lion Specialty Chemicals, DBP oil supply amount: 500 g / 100 g), and metal oxide 1 (phosphorus-doped oxidation) 15 parts by mass of tin, SP-2, manufactured by Mitsubishi Materials Electronics Chemical Co., Ltd.) are sent to the hopper, and melt kneading extrusion is performed at a temperature of 360 ° C. and a rotation speed of 200 rpm using a twin-screw kneader (KZW06, manufactured by Technobel). Went. The extruded resin composition was passed through cooling water, and then made into a pellet-shaped resin composition by a pelletizer (TSM-125, manufactured by Tanaka Co., Ltd., 100 kg / hour). Next, a cylindrical film 1 was produced by extrusion molding of the resin composition using a cylindrical mold having a diameter of 250 mm in a uniaxial melt kneader (GT-32, manufactured by Plastic Engineering Laboratory). Note that when the cylindrical film 1 was produced, the melt kneading and the mold temperature were appropriately adjusted in the range of 300 ° C to 400 ° C. The thickness of the cylindrical film 1 was 60 μm. The thickness was measured at a pitch of 10 mm in the circumferential direction using a Mitutoyo micrometer (hereinafter, all thickness measurements are the same as in Example 1).

(Example 2)
In Example 1, the cylindrical film 2 was produced similarly to Example 1 except having changed the composition as follows.
PEEK2 (151G, Victrex) 100 parts by mass Polyetherimide (PEI, Ultem1000, manufactured by sabic) 3.1 parts by mass Carbon black 2 (special black 4, manufactured by Orion, DBP oil supply amount 230 g / 100 g) 13 parts by mass -Metal oxide 1 (phosphorus dope tin oxide, SP-2, Mitsubishi Materials Electronics Chemical Co., Ltd.) 15 mass parts In addition, the thickness of the cylindrical film 2 was 60 micrometers.

(Example 3)
In Example 1, the cylindrical film 3 was produced similarly to Example 1 except having changed the composition as follows.
-PEEK3 (450PF, Victrex) 30 parts by mass-PEEK4 (150PF, Victrex) 70 parts by mass-Carbon black 3 (PrintexU, manufactured by Orion, DBP oil supply 350g / 100g) 10 parts by mass-Metal oxide 2 (aluminum) Doped zinc oxide, pazetCK, manufactured by Hakusuitec Co., Ltd.) 15 parts by mass The thickness of the cylindrical film 3 was 60 μm.

Example 4
In Example 1, the cylindrical film 4 was produced similarly to Example 1 except having changed the composition as follows.
-PEEK1 (Vesta Keep L4000G, manufactured by Daicel-Evonik) 100 parts by mass- Carbon black 4 (Denka Black, manufactured by Denki Kagaku Kogyo Co., Ltd., DBP oil supply amount: 160 g / 100 g) 7 parts by mass- Metal oxide 1 (phosphorus-doped tin oxide) SP-2, manufactured by Mitsubishi Materials Electronics Chemical Co., Ltd.) 10 parts by mass The thickness of the cylindrical film 4 was 60 μm.

(Example 5)
In Example 1, the cylindrical film 5 was produced similarly to Example 1 except having changed the composition as follows.
-PEEK2 (151G, Victrex) 100 parts by mass-Carbon black 2 (special black 4, manufactured by Orion, DBP oil supply amount 230 g / 100 g) 13 parts by mass-Metal oxide 2 (aluminum-doped zinc oxide, pazetCK, manufactured by Huxitek) 15 Part by mass The thickness of the cylindrical film 5 was 60 μm.

(Example 6)
In Example 1, the cylindrical film 6 was produced similarly to Example 1 except having changed the composition as follows.
PEEK3 (450PF, Victrex) 100 parts by mass Carbon black 1 (EC600JD, manufactured by Lion Specialty Chemicals, DBP oil supply amount 500 g / 100 g) 7 parts by mass Metal oxide 2 (aluminum-doped zinc oxide, pazetCK, 15 parts by mass of Hakusuitec Co., Ltd. The thickness of the cylindrical film 6 was 60 μm.

(Comparative Example 1)
In Example 1, the cylindrical film 7 was produced similarly to Example 1 except having changed the composition as follows.
Polymer alloy (90 parts by mass of PEEK1 and 10 parts by mass of thermoplastic polyimide (TPI, Aurum PD450, manufactured by Mitsui Chemicals, Inc.) are used)
Carbon black 2 (special black 4, manufactured by Orion, DBP oil supply amount: 230 g / 100 g) 13 parts by mass Metal oxide 1 (phosphorus-doped tin oxide, SP-2, manufactured by Mitsubishi Materials Electronics Chemical Co., Ltd.) 15 parts by mass The thickness of the film-like film 7 was 70 μm.

(Comparative Example 2)
In Example 1, the cylindrical film 8 was produced similarly to Example 1 except having changed the composition as follows.
-PEEK2 (151G, manufactured by Victrex) 100 parts by mass-Metal oxide 2 (aluminum-doped zinc oxide, pazetCK, manufactured by HakuSitec) 35 parts by mass The thickness of the cylindrical film 8 was 80 µm.

(Comparative Example 3)
In Example 1, the cylindrical film 9 was produced similarly to Example 1 except having changed the composition as follows.
PEEK3 (450PF, manufactured by Victrex) 100 parts by mass Carbon black 4 (Denka Black, manufactured by Denki Kagaku Kogyo Co., Ltd., DBP oil supply amount: 160 g / 100 g) 18 parts by mass The thickness of the cylindrical film 9 was 60 μm. It was.

(Comparative Example 4)
In Example 1, the cylindrical film 10 was produced similarly to Example 1 except having changed the composition as follows.
-PEEK4 (150PF, manufactured by Victrex) 100 parts by mass-Carbon black 3 (Printex U, manufactured by Orion, DBP oil supply amount: 350 g / 100 g)-10 parts by mass-Metal oxide 1 (phosphorus-doped tin oxide, SP-2, Mitsubishi Materials) (Manufactured by Denshi Kasei Co., Ltd.) 5 parts by mass The thickness of the cylindrical film 10 was 55 μm.

  The obtained cylindrical films 1 to 10 were each cut to a width of 300 mm, and further buffed on the entire circumference to obtain intermediate transfer belts 1 to 10. The obtained intermediate transfer belt was evaluated as follows. The evaluation results are shown in Table 1.

<Surface resistivity at 500 V and voltage dependency of surface resistivity>
The surface resistivity at 500 V and the voltage dependency of the surface resistivity are values measured on the back side of the intermediate transfer belts 1 to 10.
The voltage dependency of the surface resistivity was measured by the following method. First, the surface resistivity of the back side of the endless belt was measured using a URES probe of Hiresta UP MCP-HT450 type (manufactured by Mitsubishi Chemical Analytech Co., Ltd.), after measuring 100 V for 10 s (surface resistance at 100 V). rate). Next, the surface resistivity of the back side of the endless belt was measured using a URS probe of Hiresta UP MCP-HT450 type (manufactured by Mitsubishi Chemical Analytech Co., Ltd.), after measuring 500 V for 10 s (at 500 V). Surface resistivity). The difference between the common logarithm value of the surface resistivity at 100 V and the common logarithm value of the surface resistivity at 500 V was calculated and defined as the voltage dependency of the surface resistivity.
The voltage dependence of the surface resistivity and the number of measurement points of the surface resistivity were measured at about 20 to 60 points in the circumferential direction and 2 to 3 points in the axial direction, and the average value was taken as the measurement result.

<Crystalline endothermic peak (ΔH)>
ΔH was measured using DSC.
DSC used ThermoPlusEVO2 (manufactured by Rigaku Co., Ltd.) and measured the crystallization endothermic peak using an Al pan by measuring at 10 ° C./min in an air atmosphere. From the measurement results, “ΔH” was evaluated based on the following evaluation criteria.
-Evaluation criteria-
◎: ΔH is less than 5 J / g ○: ΔH is 5 J / g or more and less than 40 J / g ×: ΔH is 40 J / g or more

<Impedance>
The impedance was measured at 1 V and 1 kHz using IM3536 (Hioki Electric Co., Ltd.). The probe was L2000, and the electrode was a metal electrode with a diameter of 30 mm. The probe was sandwiched in the film thickness direction.

<Diphenylsulfone content>
The content of the diphenyl sulfone was measured by gas chromatography (G-3000, manufactured by Hitachi, Ltd.).

<Folding resistance (MIT test)>
In the MIT test, a test piece obtained by cutting the intermediate transfer belt into a width of 15 mm was prepared, and measurement was performed in an extrusion direction under a load of 500 g using “MIT-DA” manufactured by Toyo Seiki.

<Surface roughness>
The surface roughness was calculated by performing 3D synthesis of the surface shape using a laser microscope (LEXT OLS4100, manufactured by Olympus Corporation), under the conditions of λc = 800 μm, λs = 2.5 μm, and λf = none. The measurement was performed.

<Glossiness (Glossiness)>
The glossiness was determined by measuring 20 ° gloss with a gloss meter (PG-1, manufactured by Nippon Denshoku Co., Ltd.). From the measurement results, “glossiness” was evaluated based on the following evaluation criteria. Note that the numerical value of the evaluation standard indicates a gloss value (gloss value).
-Evaluation criteria-
A: 50 or more (150 or less)
○: 10 or more (150 or less)
X: Less than 10

<Moldability>
The resulting intermediate transfer belt is visually confirmed, the presence or absence of circular traces (silver) as traces of gas generation, and roughness on the belt due to insufficient viscosity or insufficient mold temperature (scale / melt structure) The moldability was evaluated according to the following evaluation criteria depending on the presence or absence of.
-Evaluation criteria-
◎: No silver or scale ○: No silver or scale with depth of 1um or more ×: Silver or scale with depth of 1um or more

<Real machine durability test (durability, transferability, cleaning properties)>
The obtained intermediate transfer belt is mounted on an image forming apparatus (RICOH, MP C6502, manufactured by Ricoh Co., Ltd.), and the surface coated cardboard (POD gloss coated paper, manufactured by Oji Paper Co., Ltd., average thickness 128 μm) is A4. Size vertical output and black halftone images were passed through 10,000 sheets.
Regarding durability, the presence or absence of cracks in the intermediate transfer belt after passing 10,000 sheets was visually evaluated with a 4 × loupe, and durability was evaluated based on the following evaluation criteria.
-Evaluation criteria (durability)-
◎: No crack is generated ○: Crack is generated, but there is no problem as a product ×: Crack is generated and there is a problem as a product

Regarding the transferability, the image density of the first image and the 10,000th image was visually observed, and the transferability was evaluated based on the following evaluation criteria.
-Evaluation criteria (transferability)-
◎: The first image and the 10,000th image have the same image density. ○: The 10,000th image is slightly thin, but there is no problem. Thin and impractical

Regarding the cleaning property, the image with the 10,000th image was visually observed, and durability was evaluated based on the following evaluation criteria. Cleaning on transfer belt-Evaluation criteria (cleanability)-
◎ The 10,000th image has no stain. ○ The 10,000th image has a slight stain, but there is no problem. ×: The 10,000th image has a stain.

  As described above, the present invention can be used as a direct or intermediate transfer body or medium with high durability so that an object can be efficiently adsorbed, desorbed and transported electrically and mechanically. it can. Therefore, it can be suitably used as a paper conveying belt or an intermediate transfer belt in an image forming apparatus represented by an electrophotographic apparatus.

As an aspect of this invention, it is as follows, for example.
<1> including polyether ether ketone and filler,
The filler comprises carbon and a metal oxide;
The endless belt is characterized in that the voltage dependency of the surface resistivity at 100 V to 500 V is 2 digits or less.
<2> The endless belt according to <1>, wherein a content mass of the metal oxide is equal to or greater than a content mass of the carbon.
<3> The endless belt according to any one of <1> to <2>, wherein a crystallization endothermic peak at 150 ° C. to 200 ° C. is less than 10 J / g in differential scanning calorimetry (DSC).
<4> The endless belt according to any one of <1> to <3>, wherein an impedance at 1 V and 1 kHz is 10 kΩ to 10 MΩ.
<5> The endless belt according to any one of <1> to <4>, wherein a DBP oil absorption amount of the carbon is 220 g or more with respect to 100 g of the carbon.
<6> The endless belt according to any one of <1> to <5>, wherein the content of diphenylsulfone is 350 ppm or less.
<7> The endless belt according to any one of <1> to <6>, wherein the polyether ether ketone includes two or more types of polyether ether ketones having different molecular weights.
<8> An intermediate transfer belt comprising the endless belt according to any one of <1> to <7>.
<9> Developing means for developing a latent image formed on the image carrier to form a toner image;
An intermediate transfer member on which the toner image is primarily transferred;
Transfer means for secondary transfer of the toner image primarily transferred onto the intermediate transfer member to a medium;
The intermediate transfer member includes polyether ether ketone and a filler, the filler includes carbon and a metal oxide, and the voltage dependency of the surface resistivity at 100 V to 500 V of the intermediate transfer member is 2 digits or less. There is provided an image forming apparatus.
<10> The image forming apparatus according to <9>, wherein a crystallization endothermic peak at 150 ° C. to 200 ° C. is less than 10 J / g in differential scanning calorimetry (DSC) of the intermediate transfer member.
<11> The image forming apparatus according to any one of <9> to <10>, wherein an impedance of the intermediate transfer member at 1 V and 1 kHz is 10 kΩ to 10 MΩ.
<12> The image forming apparatus according to any one of <9> to <11>, wherein a DBP oil absorption amount of the carbon is 220 g or more with respect to 100 g of the carbon.
<13> The image forming apparatus according to any one of <9> to <12>, wherein the polyether ether ketone includes two or more kinds of polyether ether ketones having different molecular weights.
<14> A full-color image forming apparatus according to any one of <9> to <13>, wherein a plurality of latent image carriers each having a developing unit for each color are arranged in series.
<15> a developing step of developing a latent image formed on the image carrier to form a toner image;
A primary transfer step of transferring the toner image onto an intermediate transfer member;
A secondary transfer step of secondary-transferring the toner image primarily transferred onto the intermediate transfer member to a medium,
The intermediate transfer member includes polyether ether ketone and a filler, the filler includes carbon and a metal oxide, and the voltage dependency of the surface resistivity at 100 V to 500 V of the intermediate transfer member is 2 digits or less. An image forming method is characterized in that there is an image forming method.
<16> The image forming method according to <15>, wherein a crystallization endothermic peak at 150 ° C. to 200 ° C. is less than 10 J / g in differential scanning calorimetry (DSC) of the intermediate transfer member.
<17> The image forming method according to any one of <15> to <16>, wherein an impedance of the intermediate transfer member at 1 V and 1 kHz is 10 kΩ to 10 MΩ.
<18> The image forming method according to any one of <15> to <17>, wherein the carbon has a DBP oil absorption of 220 g or more with respect to 100 g of the carbon.
<19> The image forming method according to any one of <15> to <18>, wherein the polyether ether ketone includes two or more kinds of polyether ether ketones having different molecular weights.
<20> A full-color image forming method according to any one of <15> to <19>, wherein a plurality of latent image carriers each having a developing unit for each color are arranged in series.

  The endless belt according to any one of <1> to <7>, the intermediate transfer belt according to <8>, the image forming apparatus according to any one of <9> to <14>, and <15 > To <20> can solve the conventional problems and achieve the object of the present invention.

500 Intermediate transfer unit 501 Intermediate transfer belt 10 Printer body

Japanese Patent No. 4563665 Japanese Patent No. 558174 Japanese Patent No. 4799214

Claims (20)

Including polyetheretherketone and filler,
The filler comprises carbon and a metal oxide;
An endless belt, wherein the voltage dependency of the surface resistivity at 100 V to 500 V is 2 digits or less.   The endless belt according to claim 1, wherein a content mass of the metal oxide is equal to or greater than a content mass of the carbon.   The endless belt according to any one of claims 1 to 2, wherein a crystallization endothermic peak at 150 ° C to 200 ° C is less than 10 J / g in differential scanning calorimetry (DSC).   The endless belt according to any one of claims 1 to 3, wherein an impedance at 1 V and 1 kHz is 10 kΩ to 10 MΩ.   The endless belt according to any one of claims 1 to 4, wherein a DBP oil absorption amount of the carbon is 220 g or more with respect to 100 g of the carbon.   The endless belt according to any one of claims 1 to 5, wherein the content of diphenylsulfone is 350 ppm or less.   The endless belt according to any one of claims 1 to 6, wherein the polyether ether ketone includes two or more kinds of polyether ether ketones having different molecular weights.   An intermediate transfer belt comprising the endless belt according to claim 1. Developing means for developing a latent image formed on the image carrier to form a toner image;
An intermediate transfer member on which the toner image is primarily transferred;
Transfer means for secondary transfer of the toner image primarily transferred onto the intermediate transfer member to a medium;
The intermediate transfer member includes polyether ether ketone and a filler, the filler includes carbon and a metal oxide, and the voltage dependency of the surface resistivity at 100 V to 500 V of the intermediate transfer member is 2 digits or less. An image forming apparatus, comprising:   The image forming apparatus according to claim 9, wherein a crystallization endothermic peak at 150 ° C. to 200 ° C. is less than 10 J / g in differential scanning calorimetry (DSC) of the intermediate transfer member.   The image forming apparatus according to claim 9, wherein an impedance of the intermediate transfer member at 1 V and 1 kHz is 10 kΩ to 10 MΩ.   The image forming apparatus according to claim 9, wherein a DBP oil absorption amount of the carbon is 220 g or more with respect to 100 g of the carbon.   The image forming apparatus according to claim 9, wherein the polyether ether ketone includes two or more kinds of polyether ether ketones having different molecular weights.   The image forming apparatus according to claim 9, wherein the image forming apparatus is a full-color image forming apparatus in which a plurality of latent image carriers having developing units for respective colors are arranged in series. A developing step of developing a latent image formed on the image carrier to form a toner image;
A primary transfer step of transferring the toner image onto an intermediate transfer member;
A secondary transfer step of secondary-transferring the toner image primarily transferred onto the intermediate transfer member to a medium,
The intermediate transfer member includes polyether ether ketone and a filler, the filler includes carbon and a metal oxide, and the voltage dependency of the surface resistivity at 100 V to 500 V of the intermediate transfer member is 2 digits or less. There is provided an image forming method.   The image forming method according to claim 15, wherein a crystallization endothermic peak at 150 ° C. to 200 ° C. is less than 10 J / g in differential scanning calorimetry (DSC) of the intermediate transfer member.   The image forming method according to claim 15, wherein an impedance of the intermediate transfer member at 1 V and 1 kHz is 10 kΩ to 10 MΩ.   The image forming method according to claim 15, wherein the carbon has a DBP oil absorption of 220 g or more with respect to 100 g of the carbon.   The image forming method according to claim 15, wherein the polyether ether ketone includes two or more kinds of polyether ether ketones having different molecular weights. 20. The full-color image forming method according to claim 15, wherein a plurality of latent image carriers having developing units for respective colors are arranged in series.