JPH0545897A - Production of belt-shaped photosensitive body - Google Patents

Abstract

PURPOSE:To allow the inexpensive and industrial production of a seamless belt-shaped photosensitive body by obtaining a seamless belt which is free from wrinkles and folding lines, is smooth, has high solvent resistance, and has a small difference in the circumferential length so as not to allow the belt to meander when the belt is driven by a roll and coating this belt with a conductive layer and a photosensitive layer. CONSTITUTION:A synthetic resin tube having thermal shrinkability is put on a porous mold body 1 and is brought into tight contact with the mold body 1 by applying heat thereto to form the photosensitive body on the tube; thereafter, an atm. pressure or liquid pressure is acted through holes 2 thereon from the inside of the mold body to press the tightly adhered tube from the inner side of the tube within the range of elastic deformation. The molding is then removed from the mold body 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a seamless belt type photoreceptor for information equipment.

[0002]

2. Description of the Related Art Several proposals have been made regarding a method of manufacturing a seamless belt-shaped photoreceptor. Japanese Patent Laid-Open No. 63-61254 proposes a method of shrinking and closely contacting a heat-shrinkable tube on a mold, forming a conductive layer and a photosensitive layer while maintaining close contact, and removing from the mold. However, in the publication, since the mold body is an elastic body, it is difficult to secure the accuracy such as roundness and straightness.

It is generally impossible to machine an elastic body, and a shrinkable tube obtained by using an elastic die obtained by a usual method satisfies required accuracy such as a difference in circumferential length. It is not possible.

When the disassembled assembly mold, which is another proposal of the publication, is used, a partition line is formed on the back surface of the tube, which is 30 to 80 μm which is usually used.
In the case of a tube having a thickness of m, the partition line on the back surface also affects the surface condition and cannot be used as an electrophotographic photoreceptor.

[0005]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned drawbacks of the prior art, and an object thereof is to obtain a seamless tube having sufficient characteristics required for a photoreceptor. . In particular, the problem to be achieved by the present invention is to obtain a seamless belt having no wrinkles or creases, having a large smoothness and solvent resistance, and having a small circumferential length difference so that meandering does not occur when driven by a roll. It is an object of the present invention to provide a method for industrially producing a seamless belt-shaped photoreceptor at low cost by applying a conductive layer / photosensitive layer to a belt.

[0006]

The present invention has been made to solve the above-mentioned problems, and its gist is to cover a porous mold body with a heat-shrinkable synthetic resin tube and apply heat thereto. After closely adhering to the mold body, a photosensitive member is formed on the tube, and then air pressure or hydraulic pressure is applied from the inside of the mold body through the hole, so that the adhered tube is deformed within the range of elastic deformation. The method for producing a belt-shaped photosensitive member is characterized in that it is pressed from the inside of the mold and pulled out from the mold.

The present invention will be described in detail below. The reason why the belt-shaped photoreceptor is manufactured by using a heat-shrinkable tube to shrink the mold is to obtain the following advantages. 1. Eliminates the difference in circumferential length so that the photosensitive tube does not meander when it is driven by a roll. 2. The inflation method eliminates the creases that occur when the obtained tube is wound up. 3. Makes operations such as coating and drying easy.

However, if the shrinkage becomes excessive and the stretching ratio after shrinking becomes too small, the resistance to the solvent used in the subsequent coating step will decrease. If the shrinkage is small, the above advantages cannot be obtained. In particular, when used as a photoconductor for a copying machine, in order to make the broken lines inconspicuous to the extent that an image does not become abnormal and to obtain the above-mentioned other advantages, the shrinkage rate in the radial direction of the tube is set to 1 to 30%. Is required and no axial shrinkage is required.

As the heat-shrinkable tube, one made of polyethylene terephthalate or polybutylene terephthalate can be used. When a tube made of polyethylene terephthalate is used, it is generally biaxially stretched, and in order to satisfy mechanical strength and solvent resistance, a stretching ratio of 2 or more is generally used.

When a cylindrical body is used as the mold body, it functions as the mold body in the radial direction but does not have the ability as the mold body in the axial direction. Therefore, the tube must be constrained to the mold to limit axial shrinkage. As shown in FIG. 1, it is preferable to provide a groove (3) outside the image area when used as a photoreceptor and fix the tube here with a band.

When the tube set in the mold is heat-shrinked, the shrinkage does not occur uniformly over the entire tube, but the adhesion to the mold occurs in a mottled island shape. If this is left as it is, the non-uniformity is enhanced and wrinkles remain when the shrinkage is completed. In order to prevent this, the surface lubricity of the mold body should be strengthened to prevent the adhered portion from being fixed to the mold body.

When the heat shrinkage is completed, the part protruding from the mold is cut and removed. Further, when the application is performed by dipping, it is desirable to remove the axial restraint portion in advance.
From this point onward, the steps of washing, coating and drying can be performed in exactly the same manner as the method for the drum base. That is, for the coating, the method described in JP-A-57-112423 can be applied, or a known method such as a spray coating method or a nozzle coating method can be applied.

For a layer-separated type photoreceptor, the coating step includes a charge generation layer and a charge transfer layer, and if necessary, a conductive layer.
This is done to provide a blocking layer. The conductive layer can be removed if the tube is conductive.

After drying, the tubular photoreceptor is removed from the mold by applying fluid pressure between the mold and the tube.
The formed layer does not crack, and the tube is expanded within the elastic deformation of the tube, and one end of the tube can be grasped by a vacuum chuck and pulled in the axial direction of the mold body to be removed from the mold body.

At this time, as a method of exerting a fluid pressure between the mold and the tube, a method of letting out the fluid from the mold is desirable. For this purpose, the mold body may be provided with a large number of minute holes (2) as shown in FIG. Since the tube expands due to the pressure of the fluid flowing out from the hole, the tube is pulled in the axial direction in that state.

When pressure is applied between the tube and the mold using air, as shown in FIG. 1, it has an air inlet / outlet (7) and an O-ring (6) for sealing. The flange (4) is fixed from at least one of the mold bodies (1) by screwing or the like. The other of the molds may be welded with a blind flange (5) as shown in FIG. It is sufficient to apply a pressure of 0.2 to 1.0 kg / cmG depending on the film thickness of the tube, and to make a space of several μm between the tube and the mold.
The film thickness of the tube is selected from the range of 20 to 100 μm.

On the other hand, it is desirable that the mold body be smooth. However, the convex object is transferred to the tube as it is, but the concave hole hardly causes surface abnormality on the tube after contraction at 2 mmφ or less. Therefore, as the mold body, a pipe having a hole of 2 mmφ or less, preferably 1 mmφ or less, or a sintered metal pipe using small-diameter particles is used. When using a perforated pipe, the burr in the hole must be removed to the extent that it does not create a strong recess.

As the material of the mold body, a material having elasticity is not desirable, and a rigid body is preferable. There is no protruding part on the surface,
It is desirable to use a material that can make a smooth and low-roughness surface and can be punched or chamfered. For example, heat resistant composite materials based on metals, ceramics, and resins are suitable.

The number of holes in the mold can be selected within a wide range. Normally, if the pressure is controlled, the air consumption for demolding is determined by the distance between the tube and the mold. Therefore,
The ratio of the total area of the holes to the total area of the mold is 1 × 10 ^-3 to 1%
The number of holes can be appropriately selected so as to be in the range.

When a sintered pipe is used, a general one used for filtration or the like is sufficient. When applying by dipping, both flanges should be screwed in and removed after shrinking,
A rubber type chuck may be inserted and gripped. In addition, when the axis of the mold body with the shrink tube set such as spray coating or nozzle coating is held horizontally and rotated to form the film, the portion that will be the rotation axis may be provided in advance on the blind flange. The pressure introducing pipe may also be used as the rotating shaft.

[0021]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. Example 1 As a heat-shrinkable tube, a circumference of 450 m manufactured by Okura Industry Co., Ltd.
m Polyethylene terephthalate tube was used.
This tube has a draw ratio of 3.5 in the radial direction, a draw ratio of 3.0 in the drawing direction, and a thickness of 50 μm.

As a mold, an aluminum drawn tube was mirror-cut with a diamond cutting tool. 5 to 15m from both ends for an outer diameter of 140mmφ, a length of 380mm, and a thickness of 4mm
A groove with a depth of 1 mm is provided at the position of m, and 5 mm from the end on the circumference.
4, 1 at each of 5, 145, 235, 335 mm positions
A hole of mmφ was opened and burrs were removed so as to be almost flat. On the mold, cut a female thread for flange mounting on one side,
The blind plate was welded to the other.

First, a Teflon-based lubricant (Locor IFL manufactured by Sumiko Lubricant Co., Ltd.) was spray-applied to a mold that had been ultrasonically cleaned using trichlene, and the polyethylene terephthalate tube cut to a length of 400 mm was molded. Then, hose bands were attached to the grooves at both ends of the mold to fix the tube. Put the mold with the tube fixed in the far infrared furnace,
The mold was rotated and heated at 200 ° C. for 5 minutes to shrink the tube and bring it into close contact with the mold. Although the adhesion started partially, no wrinkles were formed on the tube after the completion of the adhesion.

A knife was inserted near the inner edge of the tube fixing groove of the mold, the tube was cut, the hose band was removed, and only the shrinkable tube was set in the mold. Conductive paint (TEP-30 manufactured by Mitsubishi Metals Co., Ltd.)
A mold in which a tube was closely attached to a bath holding a tin antimony system) was chucked by a rubber balloon chuck, and immersed and lifted to form a conductive film having a dry film thickness of 3 μm.

Then, a blocking solution, a charge generating agent solution, and a charge transfer agent solution having the compositions shown in Tables 1, 2, and 3 were applied in the same manner to form dry film thicknesses of 0.5 μm, 0.6 μm, and 18 μm, respectively. It was Then, set the O-ring, attach the flange with the air supply and pipe to the mold, 0.5k from the air supply side.
The tube was inflated by supplying compressed air of g / cm ² G.
In this state, the end of the tube was grasped with a suction cup, pulled in the axial direction, and detached from the mold.

As a result of drawing out the obtained seamless tube photoreceptor, a uniform halftone image was obtained, and the uniformity of the coating film and the smoothness of the tube were confirmed.

[0027]

[Table 1] Blocking solution Weight part 6.6 Nylon 100 Alumina powder 30 1-Butanol 1500

[0028]

[Table 2] Charge generator liquid Part by weight Phenoxy resin 200 Azo pigment of formula (1) 100 4 Methyl / 4methoxypentanone 2 1400 Methyl ethyl ketone 600

[0029]

Table 3 Charge transfer agent liquid parts by weight Polycarbonate 100 Hydrazone compound represented by the formula (2) 88 Hydrazone compound represented by the formula (3) 22 Dioxane 50 Tetrahydrofuran 50

[0030]

[Chemical 1]

[0031]

[Chemical 2]

[0032]

[Chemical 3]

Example 2 A mold body having an outer diameter of 140 mmφ, a length of 1140 mm and a thickness of 4 m
m, and triple the number of holes used for demolding compressed air,
The same one as in Fig. 1 was used, except that the rotary shaft was attached to the blind flange. Further, all coatings including the conductive layer were carried out by nozzle coating while rotating the axis of the mold body horizontally.

In this case, the hose band for preventing axial shrinkage was removed after coating and drying. When the photoconductor was released from the mold, the photoconductor was cut into 360 mm lengths, and a drawing test was conducted in the same manner as in Example 1. As a result, a uniform halftone image was obtained, the coating film was uniform, and the tube was smooth. The sex was confirmed.

[0035]

According to the present invention, it is possible to obtain a seamless belt which has no wrinkles and creases, is smooth and has a large solvent resistance, and has a small circumferential length difference so as not to meander when driven by a roll. By coating the conductive layer and the photosensitive layer, the seamless belt-shaped photoreceptor can be industrially manufactured at low cost.

[0036]

[Brief description of drawings]

FIG. 1 is an explanatory sectional view of a mold body.

[Explanation of symbols]

 1. Mold body, 2. 2. A hole that exerts pressure. Groove for fixing the plastic tube, 4. 4. Flange with fluid inlet, Blind flange, 6. O-ring for sealing, 7. Fluid inlet and outlet.

Claims (2)

[Claims] 1. A heat-shrinkable synthetic resin tube is covered on a porous mold, and heat is applied to bring the resin into close contact with the mold to form a photoconductor on the tube. A method for producing a belt-shaped photosensitive member, characterized in that by applying atmospheric pressure or hydraulic pressure through a hole, the closely attached tube is pressed from the inside of the tube within the range of elastic deformation and withdrawn from the mold. 2. The heat-shrinkable synthetic resin tube covered with the porous mold body is restrained and heat is applied thereto to suppress axial shrinkage so as to be closely attached to the mold body.
The method described in.