JP2012058508A - Manufacturing method for conductive endless belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To propose a better manufacturing method for manufacturing a conductive endless belt having a reinforcement member on a belt base material.SOLUTION: In the method for manufacturing a conductive endless belt, a belt base material 10 is endlessly formed from a conductive resin film and a long reinforcement member 12 is disposed in one end of the belt base material 10 in crosswise direction on at least one surface, along the circumferential direction of the belt with the front end and the back end of the reinforcement member bonded. The reinforcement member is adhered to the belt base material 10 by using a heat melting type adhesive. When starting adhesion of the reinforcement member, adhesion starts from a position right after an initial non-adhesion section 12NA having a predefined length from the front end 12TP, by applying heat from the reinforcement member side and melting the heat melting type adhesive, and continues along the circumferential direction of the belt so that the reinforcement member is sequentially adhered to the belt base material until at last the initial non-adhesion section at the front end and the back end are bonded together.

Description

  The present invention relates to a conductive endless belt formed in a seamless annular shape. More specifically, the present invention relates to a method for producing a conductive endless belt employed as a transfer belt, a transfer conveyance belt, or the like in, for example, an electrophotographic apparatus or an electrostatic recording apparatus such as a copying machine or a printer, particularly a color laser printer.

  Conventionally, in an image recording process in a copying machine, a printer, etc., first, the surface of a photosensitive member (latent image holding member) is uniformly charged, and an image is projected onto the photosensitive member from an optical system and exposed to light. An electrostatic latent image is formed by erasing the charge of the toner, and then a toner is supplied to the electrostatic latent image to form a toner image by electrostatic adhesion of the toner, which is formed on paper, OHP, photographic paper, etc. A method of printing by transferring the image onto a recording medium is employed.

  In such an image recording process, a conductive endless belt formed in a ring shape using a resin material or rubber as a base material is used as a transfer member for transferring a toner image. Such a conductive endless belt is usually driven to rotate in a state of being stretched between a driving roller connected to a driving source such as a motor and a driven roller, and subjected to a transfer process.

  When the conductive endless belt used as described above oscillates between the rollers and is driven to rotate, the conductive endless belt cannot form a clear image if the position is shifted in the width direction. In particular, in a color image formed by superimposing a plurality of images, the positional deviation is fatal. Therefore, in order to prevent misalignment in the width direction, the inner peripheral side of a base material portion (hereinafter referred to as a belt base material) formed in an endless shape that forms the belt body of the conductive endless belt In the past, a technique for providing a guide rib that fits with a groove provided on the roller side at a peripheral portion of the roller and stably running it has been widely employed (for example, Patent Document 1).

  Patent Document 2 discloses a technique for preventing meandering of a conductive endless belt by pressing the conductive endless belt against a belt position regulating member in the image forming apparatus. By adopting such a technique, it is not necessary to provide guide ribs, so that the structure can be simplified and the cost can be reduced. However, since a strong force acts on the end portion of the conductive endless belt to be pressed, damage such as cracking is likely to occur, so it is necessary to provide some kind of reinforcing member. In the cited document 2, it is proposed to employ a reinforcing member made of a polymer having a bending rigidity rate equal to or less than a predetermined value and having a relationship with a bending rigidity rate of the belt base material within a predetermined range. As a result, when a force is applied to the belt end, the rigidity of the reinforcing member suppresses deformation of the belt end, preventing stress from concentrating on the belt base material, and the bending rigidity of the reinforcing member is relatively low. It is said that the conductive endless belt can be used for a long period of time because cracking is less likely to occur because it is set low.

Japanese Patent Laid-Open No. 2002-167021 JP-A-8-63000

In the cited document 2, it is recommended that the reinforcing member is formed into a tape material having an adhesive surface because of ease of handling and the like, and sufficient adhesive strength can be obtained with this (cited document 2). Paragraphs [0013], [0024], [0025], [0033]).
However, while the tape-shaped reinforcing member having an adhesive surface has advantages in terms of ease of bonding to the belt substrate and quick attachment of the reinforcing member, the belt substrate and the reinforcing member are physically bonded. It is only fixed by force. For this reason, the belt base material is such that the conductive endless belt receives a large skewing force during traveling, or the adhesive layer softens due to the temperature in the apparatus increasing by about 40 to 60 ° C. and the adhesion strength decreases. There is a possibility that separation will occur between the reinforcing member and the reinforcing member. Moreover, since the adhesive strength with a belt base material falls by embrittlement of an adhesion layer in a low-temperature environment, there is a concern about the separation between the belt base material and the reinforcing member.
Furthermore, it is required to manufacture a conductive endless belt as a finished product by fixing a long tape-shaped reinforcing member uniformly to the end of the annular belt base material with high positional accuracy. If the step of disposing the reinforcing member on the belt base material is deficient, the manufactured conductive endless belt becomes a defective product and the yield decreases.

As described above, there is still room for improvement with respect to the configuration of the conductive endless belt in which the reinforcing member is disposed on the peripheral edge of the belt base material and the manufacturing method thereof.
Therefore, the main object of the present invention is to propose a more suitable manufacturing method for manufacturing a conductive endless belt including a reinforcing member having a predetermined rigidity on a belt base material.

The above-described object is that a long reinforcing member is disposed in the belt circumferential direction at the end in the width direction of at least one side of the belt base material on which the conductive resin film is formed endlessly. A method for producing a conductive endless belt in which a tip portion and a terminal portion of a reinforcing member are joined,
The belt base material is bonded to the reinforcing member using a hot-melt adhesive,
At the start of bonding of the reinforcing member, a range of a predetermined length from the tip is set as an initial non-bonded portion, and the hot melt bonding is performed by heating from the reinforcing member side at a position where the initial non-bonded portion is released. The adhesive is melted to start bonding, and then the reinforcing members are sequentially fixed on the belt base material by bonding along the circumferential direction of the belt,
Finally, this can be achieved by a method for producing a conductive endless belt, characterized in that the initial non-bonded portion and the end portion on the tip end side are joined.

  Further, a primer layer is further provided on at least one of the belt base material and the adhesive layer made of the hot-melt adhesive or between the reinforcing member and the adhesive layer made of the hot-melt adhesive. It is preferable to adopt a structure.

  And it is preferable that the said initial non-bonding part is 2-10 mm in length from the front-end | tip part of the said reinforcement member.

According to the production method of the present invention, when the hot-melt adhesive is heated and melted and a long reinforcing member is bonded onto the belt base material, the tip is released at the start of bonding (beginning of bonding) ( Adhesion is made from the position where the tip is sent out excessively. In this way, a heating device (heater) for heating the hot-melt adhesive is provided with the belt base material by allowing it to escape from the tip as an initial non-bonding portion having a predetermined length and heating from the reinforcing member side. Since direct contact can be prevented, it is possible to produce a conductive endless belt by suppressing deformation and distortion of the belt base material surface during production and bonding the reinforcing member uniformly with high positional accuracy.
And in this invention, since the heat-fusion-type adhesive agent is employ | adopted to adhere | attach a reinforcement member on a belt base material, compared with the case where it adheres with adhesives, such as a double-sided tape, it is strong and stable. The reinforcing member can be bonded and fixed to the belt base material, and a conductive endless belt having high durability can be manufactured.

(A) is the figure which showed typically the example of the use condition of an electroconductive endless belt. (B) is the figure shown about the reinforcement member provided in the front and back of a belt base material. (C) is the figure which showed the structure which adhere | attaches a reinforcement member on a belt base material. (A) is the figure which showed a mode that the reinforcement member was formed. (B) is the figure which showed the outline of the belt manufacturing apparatus which adhere | attaches the reinforcement member with an adhesive layer on a belt base material, and manufactures an electroconductive endless belt. (C) is the figure which expanded and showed the reinforcement member on a belt base material. (A) is the figure shown in order to demonstrate the mode at the time of the adhesion | attachment start of the reinforcement member generally assumed, (b) is the figure shown in order to demonstrate the mode at the time of the adhesion start of the reinforcement member employ | adopted by this invention It is. It is the figure shown about the durability test apparatus which evaluates durability of an electroconductive endless belt.

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings.
The present invention relates to a method for manufacturing a conductive endless belt. First, a schematic configuration of a conductive endless belt that is the subject of the present invention will be described in order to facilitate understanding of the invention.
1A to 1C are views showing a conductive endless belt. FIG. 1 (a) is a diagram schematically showing an example of how the conductive endless belt 1 is used. As shown in this figure, the conductive endless belt 1 is usually placed at a predetermined position inside an electrophotographic apparatus or the like. It is used by being stretched between the arranged rollers R-1 and R-2.

The conductive endless belt 1 includes a belt base material 10 serving as a belt main body in which a conductive resin film is formed in an endless shape, and a belt circumferential direction (width direction W) at an end portion in the width direction W of the belt base material 10. The reinforcing member 12 is arranged annularly in a vertical direction. 1A shows the case where the reinforcing member 12 is provided only on one side of the left end portion, but the reinforcing member 12 may be provided on both sides as necessary. In FIG. 1A, the end portion side where the reinforcing member 12 is provided is a side pressed against a belt position regulating member (not shown) in the apparatus. Here, as illustrated in FIG. 1A, in the structure in which the reinforcing member 12 is provided only on the left side, traveling control for preventing meandering can be realized by a single contact to the left side.
And if the reinforcing member 12 is provided on both sides of the belt base material 10, there is a convenience that the structure for regulating the position on both sides and the meandering regulation standard depending on the one-sided state can be switched intentionally left and right, and both ends By providing a reinforcing member at the part, the lateral tension of the belt base material can be made uniform, the contact load on only one end side can be reduced, and the belt life can be extended.

  The reinforcing member 12 may be provided on the surface side of the belt base 10 as shown in the upper part of FIG. 1B, or as shown in the lower part, depending on the design of the conductive endless belt. 10 may be provided on the back side. Further, when the reinforcing member 12 is a resin sheet, it may be adopted as a single layer or a plurality of layers.

Further, FIG. 1 (c) is a diagram clearly showing a configuration for securely bonding and fixing the reinforcing member 12 on the belt base material 10. As shown in this figure, the conductive endless belt 1 manufactured according to the present invention includes a belt base material 10 and a reinforcing member 12 having an adhesive layer 14 made of a hot-melt adhesive (hereinafter referred to as a hot-melt adhesive). Adopting and manufacturing is one of the features.
Since the hot melt adhesive can form a strong adhesive state by chemical bonding, the belt base material 10 and the reinforcing member 12 are securely bonded and fixed, and sufficiently resistant to environmental changes such as temperature and humidity. The part can be held stably. As a result, peeling does not occur even when the external environment changes, such as a slanting force applied to the belt during traveling, and temperature and humidity fluctuations. This realizes a highly durable conductive endless belt excellent in environment resistance.
In order to obtain the adhesive force of the adhesive layer 14 more reliably, a primer layer 16 is provided between at least one of the belt base material 10 and the adhesive layer 14 or between the reinforcing member 12 and the adhesive layer 14. It is desirable to provide (FIG. 1C illustrates the case between the belt substrate 10 and the adhesive layer 14). By providing and adhering the primer layer 16, the adhesion state by chemical bonding can be further strengthened.

The belt base material 10 is made of a resin material in which additives such as a conductive material are appropriately blended with the base material resin. The belt base resin is not particularly limited. For example, nylon (polyamide (PA)) resin, acrylonitrile-butadiene-styrene (ABS) resin, polyester resin, polyethylene naphthalate resin (PEN) or poly Various resins such as butylene naphthalate resin (PBN), polyethylene terephthalate resin (PET), polybutylene terephthalate resin (PBT), polycarbonate (PC) resin, and other polyolefin resins and mixed systems thereof can be suitably used. Any two or more of these polymer alloys or polymer blends can also be used.
The most preferable base resin is nylon (polyamide resin). This is preferable from the viewpoint of excellent bending fatigue resistance of the belt and versatility. This is because the polyamide-based resin is one of resins having a strong resistance to large deformation and bending due to its molecular structure, and has good tensile resistance.

As the conductive material used for adjusting the conductivity of the belt, a polymer ion conductive agent or carbon black can be suitably used.
Examples of the polymer ion conductive agent include Irgastat (registered trademark) P18 and Irgastat (registered trademark) P22 (both manufactured by Ciba Specialty Chemicals, Inc.), Pelestat 300, 303 (manufactured by Sanyo Chemical Co., Ltd.), Examples include Sanconol TBX-310 (manufactured by Sanko Chemical Co., Ltd.), and these are readily available on the market. Specific examples of carbon black include ketjen black, acetylene black, carbon black for rubber such as SAF, ISAF, HAF, FEF, GPF, SRF, FT, MT, and carbon for ink such as oxidized carbon black. Examples thereof include black and pyrolytic carbon black. The addition amount of the polymeric ion conductive agent is usually 1 to 500 parts by mass, preferably about 10 to 400 parts by mass with respect to 100 parts by mass of the base resin, and the addition amount of carbon black is 100 parts by mass of the base resin. On the other hand, it can be about 5-30 mass parts.

Other conductive materials include, for example, lauryltrimethylammonium, stearyltrimethylammonium, octadecyltrimethylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, modified fatty acid / dimethylethylammonium perchlorate, chlorate, borofluoride Cationic surfactants such as quaternary ammonium such as hydrogenates, sulfates, etosulphate salts, benzyl halide salts (benzyl bromide salts, benzyl chloride salts, etc.); aliphatic sulfonic acids, higher alcohol sulfates Anionic surfactants such as higher alcohol ethylene oxide addition sulfates and higher alcohol phosphates; amphoteric surfactants such as various betaines; higher alcohol ethylene oxides, polyethylene glycol fats Esters, polyhydric alcohol fatty acid ester antistatic agent such as a nonionic antistatic agents such _{as, LiCF 2 SO 2, NaClO 4} , LiBF 4, periodic table Group 1 metal salts such as NaCl; Ca _(ClO 4) Group 2 metal salts of periodic table such as 2; natural graphite, artificial graphite, etc .; metals and metal oxides such as tin oxide, titanium oxide, zinc oxide, nickel, copper; conductive polymers such as polyaniline, polypyrrole, polyacetylene, etc. Etc. can also be used.

  In addition, the resin material used for the belt substrate 10 may have other functional components as desired, for example, various fillers, coupling agents, antioxidants, lubricants, surface treatment agents, pigments, ultraviolet absorbers, An antistatic agent, a dispersing agent, a neutralizing agent, a foaming agent, a cross-linking agent, and the like can be appropriately blended, and coloring may be performed by adding a coloring agent.

The thickness of the belt base material 10 is appropriately selected according to the required specification on the apparatus side where the conductive endless belt 1 is employed, but preferably within a range of 0.05 to 0.2 mm. is there.
The belt substrate 10 preferably has at least an elastic modulus of 1000 Mpa or more and a tear strength of 2N or more.
The surface roughness of the outer surface of the belt substrate 10 is preferably 10 μm or less, particularly 6 μm or less, more preferably 3 μm or less in terms of JIS 10-point average roughness Rz.

As the reinforcing member 12, it is preferable to employ a resin film having a predetermined strength or more. Such a resin film is formed of, for example, a polyamide (PA) resin, a polyester polyethylene terephthalate resin (PET), a polyphenylene sulfide resin (PPS), a polyimide resin (PI), a polyamideimide (PAI), or the like. It is preferable to employ one having at least an elastic modulus of 500 Mpa or more and a tear strength of 2N or more. Thereby, the intensity | strength of the belt base material 10 can be reinforced reliably. In consideration of strength and environmental durability (temperature resistance, humidity), it is desirable to form the reinforcing member 12 with a polyamide (PA) -based resin or a polyester-based polyethylene terephthalate resin.
The thickness of the reinforcing member 12 is appropriately adjusted depending on the material and shape of the belt base material 10 to be reinforced. For example, when the thickness of the belt base material 10 is 0.1 mm to 0.2 mm, the thickness is preferably 0.8. The range is from 05 mm to 0.3 mm, and more preferably from 0.1 mm to 0.2 mm. Moreover, it is preferable that the thickness of the reinforcing member 12 is, for example, 100 to 200% with respect to the thickness of the belt base material 10.

  The adhesive layer 14 is formed of a hot melt adhesive. Examples of hot melt adhesives include polyester hot melt adhesives, urethane hot melt adhesives, ethylene-vinyl acetate (EVA) hot melt adhesives, polyamide (PA) hot melt adhesives, and modified olefins. Those selected from the group of hot melt adhesives can be employed. In particular, it is desirable to employ a polyester hot melt adhesive because it can form a strong bond and is resistant to environmental changes in temperature and humidity. The thickness of the adhesive layer 14 is preferably about 50 μm to 150 μm.

The primer layer 16 is preferably a material selected from the group consisting of polyfunctional polyisocyanates, monoisocyanates, diisocyanates and mixtures thereof. As the primer layer 16, for example, a primer mainly composed of polyisocyanate and containing 1% or more of an isocyanate component can be preferably used. As a primer obtained by adding a synthetic resin such as ethyl acetate or vinyl acetate to an isocyanate component, Specifically, Astrobond No. 1 manufactured by Bridgestone Corporation can be preferably used. The primer layer 16 has the above primer of about 0.0001 to 0.005 g / cm ² and is at least one of the belt substrate 10 and the adhesive layer 14 or the reinforcing member 12 and the adhesive layer 14. It can form by apply | coating between.

  In the conductive endless belt 1, a primer is applied to an adhesive surface (front surface or back surface, or both surfaces) on which the reinforcing member 12 is arranged at the end of the belt base material 1, and dried to form a primer layer 16. Is desirable. In the case where the primer layer 16 is also provided between the reinforcing member 12 and the adhesive layer 14, the primer may be applied to the joint surface of the reinforcing member 12. Also, other polyisocyanate-based primers may be used depending on the processing environment and pasting processability. The primer layer 16 can be omitted, but is preferably provided from the viewpoint of realizing stronger adhesion.

Below, the manufacturing method by this invention suitable for manufacturing the electric endless belt of the structure demonstrated above is demonstrated concretely.
Further, a process for manufacturing the conductive endless belt 1 will be described with reference to the drawings. FIG. 2 shows a manufacturing process of the conductive endless belt 1, and FIG. 2A is a view showing how the reinforcing member 12 is formed. A sticking device provided with a thermocompression bonding plate by appropriately preparing a resin sheet as the reinforcing member 12, providing a primer layer 16 on the resin sheet as necessary, and further laminating an adhesive layer 14 with a hot melt adhesive in order. Are subjected to heat-pressing treatment of heat and pressure, and these are thermally welded. Thereby, the mother sheet 12A of the reinforcing member 12 having the adhesive layer 14 on one side is formed. This mother sheet 12A is in a state where a large number of reinforcing members 12 with long adhesive layers that are actually specified are connected in the width direction. Therefore, it is possible to obtain the reinforcing member 12 for reinforcing the end portion of the belt base material 10 by cutting into a predetermined size by the cutting device.

FIG. 2B schematically shows a belt manufacturing apparatus 20 for manufacturing the conductive endless belt 1 by bonding the reinforcing member 12 with the long adhesive layer prepared as described above to the belt base material 10. It is a figure.
In the belt manufacturing apparatus 20, two rollers 21R-1 and 21R-2 are arranged to stretch the belt base material 10 formed in an endless shape. One roller 11R-1 serves as a drive source and is a drive roller connected to a motor (not shown), and the other roller 11R-2 is a driven roller. Therefore, the belt base material 10 stretched between the rollers 21R-1 and 21R-2 is rotated in the arrow AR direction.

  And the belt manufacturing apparatus 20 opposes the peripheral surface of the position (width direction edge part of the belt base material 10) where the reinforcement member 12 is adhere | attached on the belt base material 10, and the hot melt which comprises the contact bonding layer 14 is comprised. A heater 22 is provided as a heating device for melting the system adhesive. The heater 22 is held by a support structure 23, and is moved to two positions, that is, a contact position and a separation position by a roller 21R-2 that is arranged to face the drive system (not shown) incorporated in the support structure 23. Can be moved. As the heater 22, a high frequency welder, an electric heater welder, an ultrasonic welder, or the like can be suitably used.

  The reinforcing member 12 with the adhesive layer prepared in FIG. 2 (a) is guided to the expected adhesion position on the belt base material 10 with the adhesive layer 14 as the lower side, and the rollers 21R-1 and 21R-2 are rotated. By pressing the heater 22, the reinforcing member 12 is bonded onto the belt base material 10 by the adhesive layer 14. FIG. 2C is an enlarged view showing a part of the reinforcing member 12 bonded to the end portion in the width direction on the belt base material 10.

By the way, when the reinforcing member 12 is bonded onto the belt base material 10 using the belt manufacturing apparatus 20 as described above, the operation is started as follows at the start of bonding (that is, at the start of bonding). Is generally assumed.
First, the front end portion of the reinforcing member 12 is securely fixed to the end portion position of the belt base material 10. Then, starting from this first fixed location, the bonding is continued in sequence, and finally the end portion of the reinforcing member 12 is abutted with the first fixed end portion, or a part is overlapped to perform the joining work. Complete.

  In the bonding step, the distal end portion of the reinforcing member 12 to be bonded is reliably positioned on the belt base material 10 and then the subsequent bonding operation is performed. However, in this case, there is a concern that the inconvenience described below occurs. This point will be described with reference to FIG. FIG. 3A is a view shown for explaining a state at the start of bonding of the assumed reinforcing member.

In the case shown in FIG. 3A, the operation is performed so that the front end portion 12TP of the reinforcing member 12 is securely fixed on the belt base material 10, so that the front end portion 12TP exists at least within the range of the heater 22. The first bond is made. By doing so, the adhesive layer 14 below the tip 12TP can be melted by the heat from the heater 22 and bonded and fixed to the belt base material 10.
However, in this case, in the rotational direction AR of the belt base material 10, a part 22 PA of the heater 22 is exposed on the upstream side of the front end portion 12 </ b> TP, and is in direct contact with the surface of the belt base material 10. become. Since heat that can melt at least the hot-melt adhesive under the reinforcing member 12 is applied from the heater 22, uneven heat deformation and distortion of the surface of the belt base material 10 that has received this heat easily occurs. This region is a region where the end portion of the reinforcing member 12 is bonded lastly and is aligned with the tip portion. If the surface becomes non-uniform, it becomes difficult to bond the reinforcing member uniformly. As a result, the straightness of the bonded reinforcing member cannot be guaranteed. As a result, there is a concern that the electric endless belt provided on the reinforcing member 12 cannot sufficiently exhibit the effects of preventing meandering and reinforcing the end portions.

FIG. 3B shows the present invention in which the conductive endless belt can be manufactured by performing the initial bonding that does not cause the above disadvantages. This is a change in the idea of stopping the idea of reliably stopping the tip 12TP as shown in FIG. 3 (a) and starting the bonding operation from a state where the tip 12TP is intentionally sent out longer. Is based.
More specifically, as shown in FIG. 3B, when the reinforcement member 12 starts to be bonded, a range of a predetermined length from the tip portion 12TP is set as the initial non-bonded portion 12NA, and the initial non-bonded portion 12NA is released. Heating is performed from the reinforcing member side at the raised position (a state where the distal end side is fed out excessively) to melt the hot-melt adhesive and perform initial bonding.
After that, the reinforcing members are sequentially fixed on the belt base material by bonding along the belt circumferential direction, and finally, the initial non-bonded portion and the end portion on the tip side are joined.

In the case shown in FIG. 3B, the heater 22 is reliably prevented from coming into direct contact with the belt base material 10 during the initial bonding, and the initial non-bonded portion 12NA and the terminal portion are abutted at the end, or The heater 22 does not come into contact with the belt base material 10 by joining in a partially overlapped state. Therefore, as pointed out in the case of FIG. 3 (a), it is possible to prevent the occurrence of a failure due to heat generated because the hot-melt adhesive is used as the adhesive.
The initial non-bonding portion 12NA is preferably set to a length range of 2 to 10 mm from the distal end portion 12TP of the reinforcing member, and more preferably set to a length of 5 to 10 mm. If the initial non-adhesive portion 12NA is less than 2 mm, the possibility that the heat from the heater 22 affects the surface of the belt base material 10 increases, and the possibility that the above-described disadvantages occur increases. That is, when the end portion of the heater 22 and the tip end portion 12TP of the reinforcing member 12 are exactly the same, the heater is not in contact with the surface of the belt base material 10, but since the distance is very close, the same heat as described above. Therefore, the initial non-bonding portion 12NA is desirably 2 mm or more. On the other hand, when the initial non-adhesive portion 12NA is longer than 10 mm, there is a disadvantage in that the portion that is not adhered and becomes dull becomes too long, making it difficult to perform the adhering work, and the workability is deteriorated. Thus, when workability | operativity worsens, a reinforcement member may not be adhere | attached straightly. In this case, the effect of preventing the meandering of the belt by the reinforcing member is reduced.

  In addition, from the viewpoint of bonding the reinforcing member 12 on the belt base material 10 more reliably, it is more desirable to manufacture after side-buffing the reinforcing member 12. As a result, in addition to the removal of the release agent on the surface of the reinforcing member, the adhesion surface area can be increased by the anchoring effect (anchor effect), so that it is effective to maintain strong adhesion characteristics.

Examples of the present invention will be further described below.
Example 1
By melt-kneading 100 parts by mass of polyamide resin (nylon 12) and 20 parts by mass of carbon black as a conductive material with a biaxial kneader, and extruding the obtained kneaded product using an annular die A belt base material 10 for a conductive endless belt having dimensions of a circumferential length of 600 mm, a width of 240 mm, and a thickness of 0.1 mm was obtained. A Bayer desmodule RE, which is a polyfunctional polyisocyanate, is applied as a primer to the region where the reinforcing member 12 is to be bonded on the outer peripheral surface of the belt base material 10 at about 0.002 g / cm ² and dried. Thus, the primer layer 16 was formed.

On the other hand, as shown in FIG. 2A, the reinforcing member 12 with an adhesive layer was prepared. Specifically, the reinforcing resin sheet has a thickness of 0.05 mm and a tensile strength of 1300 Mpa.
The same primer (Bayer's Death Module RE) as above was applied to the polyamide resin (nylon 12) to form a primer layer 16, and Elfan UH203 (polyurethane hot melt adhesive) manufactured by Nippon Matai Co., Ltd. as a hot melt adhesive , Thickness 0.05 mm) is disposed thereon as an adhesive layer 14, and the adhesive layer 14 is melted by heat to produce a reinforcing member 12 with an adhesive layer.

Using the manufacturing apparatus 20 shown in FIG. 2 (b), the conductive endless belt of Example 1 having the reinforcing member 12 at the end portion was obtained by thermally melting the adhesive layer 14 on the belt base material 10. . At the start of bonding at that time, as described above, the range of a predetermined length from the tip portion 12TP is set as the initial non-bonded portion 12NA, and heating is started from the reinforcing member 12 side at a position where the initial non-bonded portion 12NA is released. The reinforcing members were sequentially fixed on the belt substrate 10 by bonding along the direction.
In addition, the width of the reinforcing member 12 on the belt base material 10 was set to 5.0 mm, and the abutting amount (the overlapping amount of the tip portion and the end portion) was set to 0 to 3.0 mm. This conductive endless belt was attached to the durability test apparatus shown in FIG. 4 to evaluate the durability.

The durability test apparatus 100 shown in FIG. 4 includes a pair of rollers 101R-1 and 101R-2 that stretch the conductive endless belt 1. The motor 102 rotates in the direction of the arrow (in the drawing, the upper surface side is the right direction). The tension springs 103 and 103 are provided, and the tension force applied to the conductive endless belt 1 can be adjusted. In FIG. 4, the tension on the front side is set to 10N, and the tension on the back side is set to 30N. Therefore, here, the conductive endless belt 1 comes into contact with the position regulating member 104 on the back side, thereby realizing the running control with meandering prevention. Although not shown here, the reinforcing member 12 is disposed at the end on the back side. Reference numeral 105 in the drawing denotes a meandering control sensor.
An endurance running test was carried out at a running speed of 22 m / min, a test environment at a temperature of 22 ° C. and a humidity of 50%, and the tear strength at the end and the straightness of the reinforcing member after bonding were confirmed and evaluated.
In addition, when an endless belt is set in the durability test apparatus 100 and continuously run, the belt in which the reinforcing sheet is not uniformly applied is gradually meandered. This apparatus is configured to measure the amount of meandering by the sensor 105 to measure the running stability of the belt and to evaluate the distortion of the belt surface during the running of the belt as will be described later.

As shown in Table 1 below, each conductive endless belt was manufactured under the conditions described in Examples 1 to 6 and Comparative Example 1 to Comparative Example 4 as shown in Table 2, and this was evaluated. .
The initial non-bonded portion (mm) shown in Tables 1 and 2 is the length of the initial non-bonded portion 12NA.
In Comparative Example 1, “−10” indicates that the tip 12TP is 10 mm inside from the end of the heater. In Comparative Example 3, it is 0 mm when the tip portion 12TP and the end portion of the heater coincide.

The end tear strength (N / mm) was tested according to JIS-K7128 using a digital elmendorf tear tester (SA-WP type) manufactured by Toyo Seiki Seisakusho. The end tear strength is preferably 5 (N / mm) or more, and this was regarded as acceptable.
Further, the straightness of the reinforcing member after bonding is determined by irradiating the side surface of the belt base material with laser light from a KEYENCE laser displacement meter (LK-G30) and measuring the amount of change. It was confirmed whether or not it was adhered straight to the top. Since the numerical value indicates a meandering state, the smaller the number, the better. The straightness is preferably less than 0.5 (mm), and this is regarded as acceptable.
Further, the belt surface distortion was determined by irradiating the endless belt surface with laser light from a Keyence laser displacement meter (LK-G30), and determining the maximum and minimum difference between the surface irregularities as the surface strain.
Here, the determination of the belt surface distortion is x when the diameter is 2 mm or more and the depth is 5 mm or more, Δ when the diameter is 1 mm or more and less than 2 mm, and when the depth is 3 mm or more and less than 5 mm, and the diameter is less than 1 mm, and The case where the depth was less than 3 mm was evaluated as ◯, and Δ and ○ were determined as acceptable.

a) Nylon 12 resin film: Ube Industries product grade 3030XA
b) Hot melt adhesive: Nippon Matai Co., Ltd. Elfhan UH203
c) Primer: Bayer Death Module RE

As can be confirmed from Tables 1 and 2, the initial non-bonding part of 2 to 10 mm is set and the bonding is started, the reinforcing member is made uniform on the belt base material with good positioning accuracy, and conductive. It can be confirmed that this is effective for producing the endless belt 1.
And since the obtained electroconductive endless belt 1 was based on the contact bonding layer 14 by a hot-melt-type adhesive agent, it was also confirmed that the electroconductive endless belt excellent in durability was obtained.
In addition, it can confirm that a polyamide-type resin is suitable for a belt base material and a reinforcement member. Polyamide (PA) is superior to polyimide (PI) and polyamideimide (PAI) in flexibility, durability in a low temperature and low humidity environment, and has high performance of preventing cracking and cracking.

Although the said Example showed as a suitable example the case where the reinforcement member 12 is arrange | positioned on the one end part and outer peripheral surface of the belt base material 10, you may arrange | position the reinforcement member 12 in a both-sides end. In addition, it is necessary to make some changes to the bonding apparatus, but the conductive endless belt may be manufactured by disposing the reinforcing member 12 on the inner peripheral surface side of the belt base 10 depending on the design requirements.
In addition, the present invention is suitable for manufacturing a conductive endless belt that employs the reinforcing member 12 to simplify the structure without using guide ribs and to reduce the cost. However, depending on the situation, it is undeniable that the conductive endless belt adopts the guide rib and further has a reinforcing member. It goes without saying that the present invention may also be applied in such a case.

  As is apparent from the above description, according to the present invention, a conductive endless belt in which a reinforcing member is uniformly provided on the end portion of the belt base material in the belt circumferential direction can be efficiently manufactured. In addition, this conductive endless belt uses a hot-melt adhesive, so it has a simple structure and sufficient strength, and it can withstand environmental changes within the device and can be used stably for a long period of time. Become a belt. Such a conductive endless belt contributes to improving the durability of electronic devices such as copying machines and printers.

DESCRIPTION OF SYMBOLS 1 Conductive endless belt 10 Belt base material 12 Reinforcement member 12TP The front-end | tip part of a reinforcement member 12NA Initial non-adhesion part 14 Adhesive layer (thermal melting type adhesive agent)
16 Primer layer 20 Belt manufacturing equipment 22 Heater

Claims (3)

A long reinforcing member is disposed in the belt circumferential direction at the end in the width direction of at least one side of the belt base material on which the conductive resin film is formed endlessly, and the tip of the reinforcing member A method for producing a conductive endless belt in which a part and a terminal part are joined,
The belt base material is bonded to the reinforcing member using a hot-melt adhesive,
At the start of bonding of the reinforcing member, a range of a predetermined length from the tip is set as an initial non-bonded portion, and the hot melt bonding is performed by heating from the reinforcing member side at a position where the initial non-bonded portion is released. The adhesive is melted to start bonding, and then the reinforcing members are sequentially fixed on the belt base material by bonding along the circumferential direction of the belt,
Finally, a method for producing a conductive endless belt, characterized in that the initial non-bonded portion and the end portion on the tip end side are joined. A primer layer is further provided on at least one of the belt base material and the adhesive layer made of the hot-melt adhesive or between the reinforcing member and the adhesive layer made of the hot-melt adhesive. The method for producing a conductive endless belt according to claim 1. 3. The method for manufacturing a conductive endless belt according to claim 1, wherein the initial non-bonding portion has a length of 2 to 10 mm from a tip portion of the reinforcing member.