JP2000302272A - Electrostatic holding belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide excellent electrostatic attracting force by setting volumetric specific resistance of a tubular object from a room temperature to a specific temperature to a specific value or more, and keeping the volumetric specific resistance of an attracting layer from a room temperature to a specific temperature in a specific range. SOLUTION: This electrostatic holding belt 10 is constituted by forming a conductive electrode pattern 14 on a surface of a tubular object 12, and an attracting layer 16 on this electrode pattern 14. The attracting layer 16, at any temperature from a room temperature to 100 deg.C, is formed of resin single substance or compound resin with 109 to 1015 Ω.cm volumetric specific resistance, and polyethylene, polypropylene, etc., are used for it. A polymeric material for forming the tubular object 12, at any temperature from a room temperature to 100 deg.C, has 1015 Ω.cm or more volumetric specific resistance. Any polymeric material having the volumetric specific resistance can be used, such as engineering plastic. Actually, polyamide 6, polyamide 66, polyamide 46, etc., are used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic holding belt, and more particularly, to the conveyance of paper or OHP film used in an electrophotographic apparatus such as a copying machine, a laser beam printer or a facsimile, or an ink jet printer. The present invention relates to a belt capable of adsorbing an object by Coulomb force used for conveying or drying paper or an OHP film of a bubble jet printer.

[0002]

2. Description of the Related Art In an electrophotographic apparatus such as a copying machine, for example, paper is conveyed by placing the paper on a resin belt such as PC or vinylidene fluoride or by pre-charging the resin belt to impart a charge to the surface. In addition, a method is known in which paper is adsorbed and transported by the charge.

[0003] A method of transporting paper on a resin belt is as follows.
The paper and the belt often slip, making it difficult to achieve stable conveyance. On the other hand, the method of adsorbing the paper by charging the resin belt has a drawback that the paper adsorbing power is insufficient, the paper cannot be accurately fixed on the belt, and the leading end of the paper rises during the conveyance. And so on. In particular, in order to increase the speed of a printer, it is necessary to more accurately adsorb a printing medium such as paper or an OHP film to a belt and to increase the adsorbing power, and furthermore, the use environment is higher than before. Even if it changes, for example, under high temperature and high humidity, it is necessary to secure a sufficient paper suction force.

In order to obtain an electrostatic holding belt capable of strongly adsorbing a medium for printing or the like in order to increase the speed of a printer or the like, an electrode pattern is formed on the belt and a voltage is applied. There is a method in which paper is electrostatically attracted.

[0005]

[Problems to be solved by the invention]

However, in recent years, electrophotographic apparatuses, ink jet printer apparatuses, or bubble jet printer apparatuses have become smaller and faster, and the inside of the apparatus has toner
The heat generated by the drying of the ink tends to be higher and higher. For this reason, the electrostatic holding belt used in these devices needs to further improve heat resistance. In particular, when the object to be adsorbed is adsorbed to the electrostatic holding device, the voltage applied to the adsorbent layer decreases when the volume resistivity of the adsorbent layer decreases, and the charge induced in the adsorbent layer decreases,
As a result of the decrease in Coulomb force, the attraction force decreases. In a conventional conveyor belt, the change in volume resistivity is not large around room temperature, but in a device in which the internal temperature is high, such as 50 ° C. or more, the adsorption force may decrease due to a decrease in volume resistivity due to a rise in temperature. There was a problem.

The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, it has been found that the temperature dependence of the volume resistivity of the adsorption layer is reduced, thereby reducing the temperature dependence of the adsorption force. Paying attention to what can be done, the inventors have come up with an electrostatic holding belt that has a small temperature dependency of the attraction force and can maintain the attraction force even at a high temperature.

[0008]

The gist of the electrostatic holding belt according to the present invention is that a conductive electrode pattern is formed on a tubular member made of a polymer material, and the conductive pattern is formed on the tubular member. An electrostatic holding belt having an adsorbent layer formed thereon, wherein the tubular article has a volume resistivity from room temperature to 100 ° C. of 10 ¹⁵ Ω · cm or more, and the adsorbent layer has a volume resistivity from room temperature to 100 ° C. Resistance is 10 ⁹
10 to 10 ¹⁵ Ω · cm.

Further, the temperature of the adsorption layer is changed from room temperature to 100 ° C.
Volume resistivity is 10^Ten-10 ¹⁴Ω · cm, and more
Preferably 10^Ten-10¹³Ω · cm.

[0010] The adsorption layer may be formed by adding a conductive material to a resin having a volume resistivity of 10 ¹⁵ Ω · cm or more at room temperature to 100 ° C.

The conductive material may be at least one selected from the group consisting of carbon black, graphite, metal, conductive metal oxide, metal oxide, and antistatic agent.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of an electrostatic holding belt according to the present invention will be described in detail with reference to the drawings.

The electrostatic holding belt 10 transports paper or OHP film in an electrophotographic apparatus such as a copying machine, a laser beam printer or a facsimile.
Alternatively, it can be used for a belt used for transporting or drying paper or OHP film of an ink jet printer device or a bubble jet printer device.

As shown in FIGS. 1 and 2, in the electrostatic holding belt 10 according to the present invention, an electrode pattern 14 having conductivity is formed on the surface of a tubular object 12 and the electrode pattern 14 is formed on the electrode pattern 14. The suction layer 16 is formed. This adsorption layer 16 has a volume resistivity from room temperature to 100 ° C. of 10 ⁹ to 10 ¹⁵ Ω · cm. here,
In the present specification, “the volume resistivity at room temperature to 100 ° C. is 10 ⁹ to 10 ¹⁵ Ω · cm” is from room temperature to 1 Ω · cm.
It shows that the volume resistivity is 10 ⁹ to 10 ¹⁵ Ω · cm at any temperature at 00 ° C. The same applies hereinafter.

The polymer material forming the tubular article 12 of the present invention has a volume resistivity from room temperature to 100 ° C. of 10 ¹⁵
Ω · cm or more. As long as it is a polymer material having this volume resistivity, it is not particularly limited, and for example, there is an engineering plastic. Specifically, polyamide 6, polyamide 66, polyamide 46, polyamide MXD6, polycarbonate, polyacetal, polyphenylene ether, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), PEN
(Polyethylene naphthalate), polyarylate, liquid crystal polyester, polyphenylene sulfide, polysulfone, polyethersulfone, polyetheretherketone, polyetherimide, polyamideimide, aramid, non-thermoplastic polyimide, thermoplastic polyimide, fluorine resin, ethylene vinyl Preferably, but not limited to, one or more combinations selected from the group consisting of alcohol copolymers, polymethylpentene, phenolic resins, unsaturated polyester resins, epoxy resins, silicones, and diallyl phthalate resins .

Under the conditions of use of the above-mentioned belt, the tubular material constituting the base of the electrostatic holding belt 10 is 10
Because it is necessary to be able to withstand high temperatures of about 0 ° C,
It is preferably made of a heat-resistant resin, and from the viewpoint of mechanical properties and the like, among the above-mentioned polymer materials, a non-thermoplastic polyimide resin or a thermoplastic polyimide resin can be exemplified.

A thermoplastic polyimide film is different from a conventional non-thermoplastic (thermosetting) polyimide film,
Since it has heat resistance, has melt fluidity in a predetermined high temperature range, and is excellent in workability, it is suitably used as a tubular member of the electrostatic holding belt according to the present invention. Moreover, the adhesiveness of the joint portion in the heat-resistant resin belt of the present invention is superior to that of the non-thermoplastic polyimide film.

Further, the above polymer material may be further provided with mechanical strength by filler, fiber or the like.

An electrode 14 having a predetermined pattern is formed on the surface of the tubular object 12. The electrode patterns 14 are configured such that the ends thereof are alternately extended to apply a voltage.
The electrode pattern 14 is made of a conductive paste made of silver, copper, aluminum, carbon, or the like.
6 is screen-printed, or a metal foil or metal thin film such as aluminum or copper is applied to the surface of the tubular object 12 and then etched to form a predetermined pattern or a predetermined pattern. A predetermined pattern is formed by evaporating a metal such as aluminum through the formed mask. The electrode pattern 14 is not limited to the illustrated shape. For example, the electrode pattern 14 may be formed in a comb shape, and may be a pattern in which the comb teeth mesh with each other.

The thickness of the electrode pattern 14 is the same as that of the electrode pattern 1.
Taking into account the surface irregularities due to 4, the thickness is preferably 2 to 30 μm, and more preferably 5 to 20 μm. Further, the electrode pattern 14
The line width and the pitch are arbitrary and can be variously set.

Further, an adsorbing layer 16 is formed on the outer surface of the tubular member 12 on which the electrode pattern 14 is formed, and protects the electrode pattern 14 from external force and adsorbs paper by the Coulomb force on the surface. .

The body of the adsorption layer 16 at a temperature from room temperature to 100 ° C.
The product specific resistance is 10⁹-10¹⁵Ω · cm, preferably
Is 10^Ten-10¹⁴Ω · cm, more preferably 10^Ten~
10 ¹³It is a simple resin or a composite resin having Ω · cm.
Here, the composite resin is a resin whose volume resistivity is adjusted
To add conductive additives and other properties
For example, a resin obtained by mixing a high dielectric constant additive and the like.

If the volume resistivity is less than 10 ⁹ Ω · cm, insulation between the adjacent electrodes 14 is insufficient, and a leak current flows. When the volume resistivity exceeds 10 ¹⁵ Ω · cm, it is difficult for electric charges to be induced on the surface of the adsorption layer 16, and the adsorption force is reduced. Further, even after the voltage applied to the electrodes is removed, the residual charge remains for a long time, and the paper remains adsorbed, which is not preferable.

When the adsorbing layer is a composite resin, the adsorbing layer 16 is adjusted to have the above-mentioned predetermined volume specific resistance by appropriately mixing a conductive material with the resin constituting the adsorbing layer.
The resin as the base material constituting the adsorption layer is from room temperature to 100
It is preferable that the volume resistivity at 10 ° C. is 10 ¹⁵ Ω · cm or more. Thus, the volume resistivity is 10 ¹⁵ Ω
Since the resin having a cm or more is less likely to exhibit ionic conductivity and has low temperature dependence, it is suitable as a resin constituting an adsorption layer having low temperature dependence of adsorption power.

The resin that can be used as the substrate having a volume resistivity of 10 ¹⁵ Ω · cm or more from room temperature to 100 ° C. may be the same as the polymer material used for the above-mentioned tubular material. , Polypropylene, polymethylpentene, norbornene resin, BR, IR, E
Polyolefin resins such as PM, EPDM, IIR, norbornene rubber, olefin thermoplastic elastomer, and acrylic resins such as polymethyl methacrylate and ethylene acrylic rubber, AAS, AES, AS, AB
S, MBS, polystyrene, SBR, styrene resin such as styrene thermoplastic elastomer, other polyphenylene sulfide, polyether ether ketone, polyimide, vinyl chloride, vinylidene chloride, vinyl carbazole, polyphenylene oxide, acrylonitrile-butadiene copolymer, 1 from room temperature such as chlorinated polyether
A resin having a volume resistivity at 00 ° C. of 10 ¹⁵ Ω · cm or more may be used. Also, a combination of two or more resins selected from these may be used, but the present invention is not limited thereto. Among these, when the electrostatic holding belt 10 of the present invention is in an environment where it is exposed to a high temperature, the resin forming the adsorption layer 16 preferably has heat resistance.

Examples of the conductive material used for adjusting the volume resistivity of the adsorption layer 16 include oxide fillers such as titanium oxide, barium titanate, and ferrite, carbon powder, graphite, metal powder, and metal oxide powder. And a metal oxide and an antistatic agent that have been subjected to a conductive treatment, and at least one or more conductive materials selected from these depending on the purpose are used.

The amount of the conductive material to be added is appropriately set depending on the intended volume resistivity of the adsorbing layer 16, and is usually preferably 2 to 50 vol%, and more preferably 3 to 30 vol%, based on the total volume of the adsorbing layer. % Is more preferred. The conductive material is preferably a powder, and the size thereof is appropriately selected depending on the purpose. However, the average particle size is usually preferably 50 μm or less, more preferably the average particle size is 10 μm or less, and the average particle size is preferably 10 μm or less. Those having a particle diameter of 1 μm or less are more preferred. These are mixed and the room temperature of the adsorption layer 16 is set to 100 ° C.
Is 10 ⁹ to 10 ¹⁵ Ω · cm, preferably 10 ¹⁰ to 10 ¹⁴ Ω · cm, more preferably 10 ¹⁰ to 10 ¹⁴ Ω · cm.
¹⁰ to 10 ¹³ Ω · cm.

As described above, a polymer material having a high volume resistivity of 10 ¹⁵ Ω · cm or more from room temperature to 100 ° C. is mixed with a conductive oxide semiconductor filler or carbon black to obtain a volume resistivity. Resistance is 10 ⁹ to 1
In the adsorption layer adjusted to 0 ¹⁵ Ω · cm, the conduction mechanism is mainly based on the tunnel conduction of electrons, and the temperature dependence of the volume resistivity can be reduced. At the same time, the volume resistivity of the tubular material made of a polymer material is also 10 ¹⁵ Ω · c.
By not changing it to m or more, the adsorption power can be maintained with little temperature dependency.

Next, an example of a method for manufacturing the electrostatic holding belt 10 will be described. However, the method for manufacturing the electrostatic holding belt of the present invention is not limited to the following example.

First, after forming a film from a polymer material in advance, both ends of the film are joined to form a belt to obtain a tubular material 12, and an electrode pattern 14 is formed on the surface of the tubular material 12. Further, the adsorbing layer 16 is formed by, for example, a coating method except for the end portions of the electrode patterns 14 that extend alternately on the outer surface thereof, and the electrostatic holding belt 10 is manufactured.

Further, as shown in FIG. 3, after the electrode pattern 14 is formed on the surface of the polymer material film 18, an adsorption layer 16 is further formed as shown by a two-dot chain line.
The electrostatic holding belt 10 may be manufactured by joining both ends of the film 18 to form a belt. Further, after the electrode pattern 14 is formed on the surface of the polymer film 18, the both ends of the film 18 are joined to form a belt, and then the suction layer 16 is further formed to manufacture the electrostatic holding belt 10. Can also.

Further, the tubular article may be formed by a casting method.

The adsorbing layer 16 is formed by coating the raw material resin in a varnish form and applying the varnish on the electrode pattern 14, or by forming the raw material resin of the adsorbing layer in a film form in advance and forming the film into an electrode. It can be formed by laminating on the pattern 14. Examples of the latter lamination method include, but are not limited to, a thermocompression method using a hot press method or a hot roll method.

The method for producing the electrostatic holding belt of the present invention can be appropriately selected according to the purpose of the obtained electrostatic holding belt, and is appropriately selected according to the material of the tubular object 12. Further, the manufacturing method can be appropriately set in accordance with the structure of another electrostatic holding belt described below.

The structure of the electrostatic holding belt is, in addition to those shown in FIGS. 1 and 2, for example, as shown in FIG. 4, on the electrode pattern 14 and the adsorbing layer 16 laminated on the outer peripheral surface of the tubular body 12, and An outer peripheral layer 20 that protects the adsorption layer 16 may be formed. As the outer peripheral layer 20, for example, any resin that can be a material of the adsorption layer 16 can be used.

Further, as shown in FIG. 5, in the electrostatic holding belt 28 in which the electrode pattern 14 and the adsorbing layer 16 are laminated on the outer peripheral surface of the tubular object 12, the adsorbing layer 16 is provided on the inner peripheral surface side of the tubular object 12. The electrostatic holding belt 30 may be configured by providing the resin layers 26 made of the same material with substantially the same thickness. In this case, by making the cross-sectional structure substantially symmetrical except for the electrode pattern 14, warpage of the electrostatic holding belt can be prevented. Further, the embodiments of FIGS. 4 and 5 may be combined.

As shown in FIG. 6, an electrode pattern 14 and an adsorbing layer 16 are laminated on the outer peripheral surface of the tubular object 12, and the electrode pattern 34 and the adsorbing layer 16 are similarly formed on the inner peripheral surface of the tubular object 12. It is also possible to form the electrostatic holding belt 38 by laminating the layers 36. The electrode pattern 34 formed on the inner peripheral surface side of the tubular object 12 may be located symmetrically with the electrode pattern 14 on the outer peripheral surface side as shown in FIG. May be at an intermediate position. As described above, by providing the electrode pattern 34 also on the inner peripheral surface side of the tubular member made of a polymer material to make the cross-sectional structure substantially symmetric, it is possible to prevent the occurrence of warpage or the like even for long-term use. Can be.

Although the electrostatic holding belt according to the present invention has been described above, the above-described embodiment is merely an example, and it is needless to say that the present invention is not limited thereto. In addition, the present invention is applied to various improvements, corrections, and modifications based on the knowledge of those skilled in the art without departing from the spirit of the present invention, such as performing various treatments on the surface of the obtained electrostatic holding belt. Can be implemented.

[0039]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but it should not be construed that the invention is limited thereto.

Example 1 Non-thermoplastic polyimide film having a thickness of 75 μm (Apical 75NPI: manufactured by Kanegafuchi Chemical Co., Ltd., volume resistivity 1 from room temperature to 100 ° C.)
0 ¹⁵ to 10 ¹⁶ Ω · cm) using an epoxy-based silver paste, as shown in FIG.
A counter electrode pattern 14 having a thickness of 10 mm and a thickness of 10 μm was formed.

Separately, an elastomer resin milastomer manufactured by Mitsui Chemicals, Inc. (volume resistivity 1 from room temperature to 100 ° C.)
0 ¹⁵ to 10 ¹⁸ Ω · cm) with barium titanate
0% by volume was mixed and kneaded to prepare a sheet having a thickness of 100 μm. The specific volume resistance of the prepared sheet from room temperature to 100 ° C. was 10 ¹¹ to 10 ¹⁴ Ω · cm. Next, this sheet was heat-sealed on the counter electrode of the polyimide film to prepare an electrostatic adsorption sheet.

The ends of the sheets were joined to produce an electrostatic holding belt shown in FIG. In order to measure the paper attraction force of the electrostatic attraction belt 10, a DC voltage of 3 kV is applied between the electrodes of the electrode pattern 14, and at normal temperature and normal humidity (20 ° C. and 60%) as shown in FIG. A4 size paper 40 was adsorbed to the belt 10. Thereafter, the paper 40 was pulled in a direction parallel to the surface of the belt 10 in the direction of the arrow in the figure, and the maximum force when the paper 40 moved was measured as the suction force. FIG. 9 is a graph showing the temperature dependency of the attraction force. As can be seen from the figure, the temperature dependence of the attraction force is small.

(Example 2) A non-thermoplastic polyimide film (Apical 75NPI, manufactured by Kanegabuchi Chemical Industry Co., Ltd.) having a thickness of 75 μm was coated with an epoxy-based silver paste, as shown in FIG. A counter electrode pattern 14 having a distance of 3 mm and a thickness of 10 μm was formed.

Separately, 20% by volume of titanium oxide was mixed and kneaded with an elastomer resin milastomer manufactured by Mitsui Chemicals, Inc. to prepare a sheet having a thickness of 100 μm. The specific volume resistance of the prepared sheet from room temperature to 100 ° C. is 10 ¹¹
〜１０10 ¹⁴ Ω · cm. Next, this sheet was heat-sealed on the counter electrode of the polyimide film to prepare an electrostatic adsorption sheet. Thereafter, an electrostatic attraction belt was manufactured in the same manner as in Example 1.

The paper suction force of the electrostatic suction belt 10 was measured in the same manner as in Example 1. FIG. 9 is a graph showing the temperature dependency of the attraction force. As can be seen from the figure, the temperature dependence of the attraction force is small.

Comparative Example 1 A non-thermoplastic polyimide film having a thickness of 75 μm (Apical 75NPI, manufactured by Kaneka Chemical Co., Ltd.) was coated with an epoxy-based silver paste, as shown in FIG. A counter electrode pattern 14 having a distance of 3 mm and a thickness of 10 μm was formed.

Next, 100 μm thickness manufactured by Central Glass Co., Ltd.
Cefral soft film (Grade: G150F20
0, volume resistivity from room temperature to 100 ° C., 10⁸~
10 ¹⁴Ωcm) of the above-mentioned polyimide film
It was heat-sealed on the top to produce an electrostatic adsorption sheet. Then real
An electrostatic attraction belt was manufactured in the same manner as in Example 1.

The paper suction force of the electrostatic suction belt was measured in the same manner as in Example 1. FIG. 9 is a graph showing the temperature dependency of the attraction force. As can be seen from the figure, the electrostatic attraction belt of the comparative example has a large temperature dependence of the attraction force and hardly attracts at 100 ° C.

[0049]

In the electrostatic holding belt according to the present invention, since the tubular member made of a polymer material and the adsorbing layer have a predetermined volume specific resistance and hardly depend on temperature, an excellent electrostatic adsorbing force can be obtained. , Paper, OHP, etc., can be sufficiently absorbed and conveyed.

[0050]

[Brief description of the drawings]

FIG. 1 is an explanatory plan view of a main part of an electrostatic holding belt according to the present invention.

FIG. 2 is an enlarged sectional explanatory view of a main part of the electrostatic holding belt shown in FIG.

FIG. 3 is an explanatory plan view of an essential part showing an embodiment of a method for manufacturing an electrostatic holding belt according to the present invention.

FIG. 4 is an enlarged sectional explanatory view of a main part showing another embodiment of the electrostatic holding belt of the present invention.

FIG. 5 is an enlarged sectional explanatory view of a main part showing still another embodiment of the electrostatic holding belt of the present invention.

FIG. 6 is an enlarged sectional explanatory view of a main part showing still another embodiment of the electrostatic holding belt of the present invention.

FIG. 7 is an enlarged sectional explanatory view of a main part showing an embodiment in which the electrostatic holding belt of the present invention is a transport belt.

FIG. 8 is a diagram showing a method for measuring the tensile attraction force of the electrostatic holding belt of the present invention.

FIG. 9 is a graph showing the relationship between the temperature and the attraction force of the electrostatic holding belt according to the example.

[Explanation of symbols]

 10, 24, 28, 30, 38: Electrostatic holding belt 12: Tubular object made of polymer material 14, 34: Electrode pattern 16, 36: Adsorption layer 18: Polymer material film 20: Outer layer 22, 26, 32: Resin layer 40: paper

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yoshiji Sezaki 2-1-1 Hiei Tsuji, Otsu City, Shiga Prefecture AB01H AD11C AD11H AK01A AK01C AR00B AR00C BA03 BA07 BA10A BA10C CA21C CA22C DA11 GB41 JD14C JD14H JG01B JG04 JG04C YY00 YY00C 4F209 AD03 AD05 AE03 AG03 AG16 AH33 NA13 NB01 NG05 NW05

Claims (5)

[Claims] 1. A conductive material is placed on a tubular material made of a polymer material.
Is formed, and the electrode pattern is formed.
An electrostatic holding belt with an adsorption layer formed on the turn
Thus, the volume specific resistance of the tubular article from room temperature to 100 ° C.
Anti 10¹⁵Ω · cm or more and from the room temperature of the adsorption layer
Volume resistivity at 100 ° C is 10 ⁹-10¹⁵Ω ・ c
m, the electrostatic holding belt. 2. The method of claim 1 wherein the temperature of the adsorption layer is from room temperature to 100 ° C.
Volume resistivity is 10 ^Ten-10¹⁴Ω · cm.
2. The electrostatic holding belt according to 1. 3. The method according to claim 1, wherein the temperature of the adsorption layer is from room temperature to 100 ° C.
Volume resistivity is 10 ^Ten-10¹³Ω · cm.
3. The electrostatic holding belt according to 2. 4. The adsorption layer according to claim 1, wherein the adsorption layer is formed by adding a conductive material to a resin having a volume resistivity at room temperature to 100 ° C. of 10 ¹⁵ Ω · cm or more. Electrostatic holding belt. 5. The method according to claim 1, wherein the conductive material is carbon black,
Graphite, metal, conductive metal oxide, metal oxide,
At least one selected from the group represented by an antistatic agent,
The electrostatic holding belt according to claim 1.