JP2517996B2 - Seamless belt manufacturing method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a seamless belt that can be used as a photoconductor for a copying machine, an electrostatic recording belt, a sheet conveying belt, or the like.

2. Description of the Related Art As a base material for an electrophotographic photoreceptor, a material using an aluminum pipe or a sheet obtained by vapor-depositing a metal such as aluminum on a polyester film is mainly used. In the case of a sheet-shaped photoreceptor, it is used by winding it around a pipe or as a seamed belt type photoreceptor formed into a belt by a method such as ultrasonic welding at both ends.

In the case of the seamed belt type photoconductor, unlike the drum type photoconductor, there is an advantage that the shape of the photoconductor can be freely set, so that the arrangement of subsystems in the copying machine can be varied. By using a transparent belt, subsystems such as an illumination system can be housed inside the belt, which is effective for realizing a compact and multifunctional machine.

However, in the conventional seamed belt type photoconductor, since a sheet-shaped member is bonded as described above, there is a portion where the photoconductor does not exist or a bonding portion, and an image cannot be formed in this portion. Therefore, there is no advantage that a large-area image can be obtained even with a small circumference as in the case of a drum-type photoconductor, and a photoconductor having an area larger than that of copy paper is required. Can not.

The electrostatic recording belt has the same advantages and disadvantages as described above.

Therefore, the use of a seamless belt as a photoconductor for a copying machine and a belt base material for electrostatic recording has been studied.

Extrusion molding, inflation, blow molding, and dip coating can be used to manufacture the seamless belt.
No. 61-273919) and several methods such as spray coating are known.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention By the way, a belt formed by a conventionally known method is practically used as a photoconductor for a copying machine or a belt base material for electrostatic recording in terms of dimensional stability, surface property and the like. Is still at an inadequate level.

For example, in the case of extrusion molding, the obtained belt has many defects such as protrusions and holes, and the smoothness is not sufficient.
In the case of the inflation method, a fold line is formed at the time of winding, and it does not make sense as a seamless belt. Further, in the case of the blow molding method, marks of the mold are generated on the surface of the belt, and the smoothness at the mold joint portion is impaired.

It is also possible to apply a film forming coating solution to the pipe surface by a dip coating method or a spray coating method and peel off the formed coating film, but the coating film generally undergoes heat shrinkage after drying treatment, In this method, it is difficult to peel the seamless layer formed on the pipe surface from the pipe, because stress is applied in the direction of compressing the pipe. Further, even if a release agent is applied to the surface, it is difficult to improve it.

On the other hand, a method in which a resin coating solution is applied onto a flexible seamless metal foil belt by a dip coating method, and then the metal foil belt is bent to peel off the seamless belt (JP-A-61).
No. 273919), it is not easy to control the surface of the belt to be smooth, and it is impossible to control the belt to an arbitrary surface state.

In recent years, in the electrophotographic recording method using a coherent light source such as a laser printer, when the surface of the base material is smooth, interference fringes are generated between the surface of the photoconductor and the base material. As a countermeasure against this, it is necessary to roughen the surface of the substrate in the range of about 0.1 to 2 μm in the thickness direction. If the degree of roughening is less than this range, there is no effect of preventing interference fringes, and if the surface is rough, secondary deterioration in image quality such as resolution deterioration, uneven charging, poor cleaning performance, etc. occurs. Will end up. Of course,
When using a non-coherent light source, it is desirable that the light source is as smooth as possible. As described above, when a coating film is formed on the outer surface of the pipe or the outer surface of the flexible seamless metal foil by the dip coating method, it is completely impossible to control such surface condition.

As described above, a method for producing a satisfactory seamless belt which can be practically used as a photoconductor for a copying machine or a belt base material for electrostatic recording has not yet been established.

The present invention has been made in view of the above problems in the conventional technique.

An object of the present invention is to provide a method for producing a seamless belt that can be used as an electrophotographic photosensitive member or an electrostatic recording belt.

Means and Actions for Solving the Problem A method for manufacturing a seamless belt according to the present invention is a jig having a smooth cylindrical inner surface immersed in a coating solution contained in a dip coating tank and then pulled up. A resin film is formed on the inner surface of the cylindrical mold, and the resin film is peeled off.

FIG. 1 shows a schematic structure of a dip coating device used in the present invention. In the present invention, for example, a cylindrical jig 1 such as an aluminum pipe having a smooth inner surface is attached to a pipe chuck device 2. It is fixed and immersed in the coating liquid 4 contained in the coating tank 3. In addition, 5 is a liquid leakage prevention collar attached to a cylindrical jig for preventing the coating liquid from adhering to the outer surface of the pipe. Then, the cylindrical jig is pulled up to form a resin film on the inner surface. This resin film is peeled off from the inner surface by any means,
Form a seamless belt.

The jig having a smooth cylindrical inner surface that can be used in the present invention has a cylindrical space inside, such as a pipe-shaped one or a block-shaped one in which the inside is hollowed out, Any shape may be used as long as the inner surface is smooth and a coating film can be formed by the dip coating method.

As the material of the jig, any material can be used as long as it is not attacked by the solvent used, and examples thereof include various metals such as aluminum, nickel, iron or stainless steel, and synthetic resins such as Teflon or polyethylene. can give. Further, composites in which metal surfaces are coated with Teflon or polyethylene or the like can also be used.

As described with reference to FIG. 1, this jig has a resin layer formed on the inner surface thereof by immersing the jig in a coating liquid in which the resin is dissolved so that the inner surface of the jig is dipped and then withdrawing the jig. However, at this time, the resin attached to the outer surface of the jig is unnecessary and is difficult to peel off.Therefore, in order to prevent the resin from being applied to the outer surface, the jig outer surface and the coating tank are It is preferable to provide a liquid invasion prevention means, for example, a liquid leakage prevention collar in FIG.

In order to improve the releasability, it is possible to apply a release agent to the inner surface of the jig in advance or mix the release agent into the coating liquid. As such a releasing agent, known ones are used, for example, zinc, calcium or magnesium salts of higher fatty acids such as stearic acid, dioctyl phosphate monoethanolamine salt and the like are preferably used.

In the present invention, since the surface property of the seamless belt is determined by the surface property of the inner surface of the jig, the inner surface of the jig is processed in advance so as to have a desired surface state, and thereby the desired surface property is obtained. A seamless belt can be obtained.
For example, if the inner surface of the jig is mirror-finished, a seamless belt having a very smooth mirror surface can be obtained. Further, as described above, if a desired roughening is performed to prevent interference fringes, a seamless belt that can be used in an electrophotographic recording method using a coherent light source can be formed.

In the present invention, various resins can be used as the resin forming the resin film. For example, polyimide resin, polyamideimide resin, polybenzimidazole resin, polyphenylene sulfide resin, polyetherketone resin, fluororesin, aramid resin, silicone resin, polyetherimide resin, polymaleimide resin, polyparapanic acid resin, polyesterimide resin , Epoxy resin, polyoxadiazole resin, polyacrylate resin, polyether sulfone resin, polyethylene naphthalate resin, polyhydantoin resin, polysulfone resin, polycarbonate resin, polyurethane resin, etc.
It can be used alone or as a mixture.

In the present invention, if desired, in order to make the seamless belt conductive, carbon, ITO, tin oxide, antimony oxide, tungsten oxide, conductive powder such as molybdenum oxide or metal whiskers are mixed and applied to these resins. It is also possible. Furthermore, it is also possible to form a seamless belt having a laminated structure, for example, a two-layer structure of a dielectric layer and a conductive layer, by laminating a plurality of layers and then peeling them off.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist is not exceeded.

Example 1 As shown in FIG. 1, a liquid leakage prevention collar 5 was attached to prevent the coating liquid from adhering to the outer surface of the pipe, and as the cylindrical jig 1, an aluminum pipe having an inner diameter of 120 mm and having a mirror-finished inner surface was prepared. It was fixed by the pipe chuck device 2. In a coating tank 3, a coating solution 4 in which a bisphenol Z type polycarbonate (molecular weight: 77,000) having a solid content of 12% by weight is dissolved in methylene chloride is placed, and the above aluminum pipe is immersed in the coating solution to obtain 100 mm / It was pulled up at a speed of min to form a resin layer on the inner surface of the aluminum pipe. After removing the aluminum pipe from the pipe chuck, it was dried at 120 ° C. for 10 minutes. Then, a spatula having a sharp tip is inserted between the inner surface of the aluminum pipe and the resin layer to peel off a part of the resin, and then air is injected into the thin area by an air gun to inject resin from the inner surface of the aluminum pipe. The layers were peeled off. By cutting both ends of the obtained resin layer, a seamless belt having a smooth surface property with a film thickness of 80 μm was obtained.

Comparative Example 1 A mirror-finished rigid aluminum pipe having an outer diameter of 120 mmφ was closed at the top and bottom, the aluminum pipe was dipped in the same coating solution as in Example 1 and applied in the same manner as in Example 1, Drying was performed to form a seamless resin layer on the outer surface of the aluminum pie. A spatula was put between the outer surface of the aluminum pipe and the formed resin layer, a part was peeled off, and air was injected by an air gun,
Since the aluminum pipe and the resin were in close contact with each other, the seamless resin layer could not be peeled off without damage.

Example 2 Using the same apparatus as in Example 1, 17% by weight of polyimide (copolymerization reaction product of benzophenone tetracarboxylic acid dianhydride and 4,4-diphenylmethane diisocyanate, 2,4-toluene diisocyanate) and 0.4 After dipping an aluminum pipe in a dimethylformamide solution of a mold release agent consisting of% nodiooctyl phosphate monoethanolamine (Cepar 44-100, manufactured by Chukyo Yushi Co., Ltd.), the aluminum pipe was pulled up at a speed of 300 mm / min, and 200 ° C. And dried for 10 minutes. Then, the coated material was peeled off from the inner surface, and both ends were cut to obtain a uniform seamless belt having a film thickness of 40 μm.

EFFECTS OF THE INVENTION The present invention has a configuration as described above, and therefore is uniform,
A smooth seamless belt having a desired surface condition can be easily obtained. The seamless belt formed by the method of the present invention has good dimensional stability, and the surface property can be arbitrarily controlled, and if desired, it can be made electrically conductive or insulative. It can be used particularly advantageously as a seamless belt such as an electrographic belt. Further, it can be used as a belt in other fields.

[Brief description of drawings]

FIG. 1 is a perspective view of a dip coating apparatus used in the present invention. 1 ... Cylindrical jig, 2 ... Pipe chuck device, 3 ...
Coating tank, 4 ... Coating liquid, 5 ... Color to prevent liquid leakage.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masanori Murase 1600 Takematsu, Minamiashigara City, Kanagawa Fujizerox Co., Ltd. Takematsu Office (56) References JP 64-1532 (JP, A)

Claims (1)

(57) [Claims] 1. A resin film is formed on the inner surface of a cylindrical mold of a jig by immersing a jig having a smooth cylindrical inner surface in a coating solution contained in a dip coating tank and pulling it up. A method for producing a seamless belt, which comprises peeling a film.