JPS60178454A - Image bearing member - Google Patents

Abstract

PURPOSE:To provide an image bearing member small in friction scratches and toner melt adhesion, and superior in electric and mechanical strength by forming a surface layer through heat shrinking a cylindrical heat-shrinkable film made of polychlorotrifluoroethylene. CONSTITUTION:A material resin 1 made of polychlorotrifluoroethylene is melted with heat, extruded through a cylindrical die 2, and at the same time, inflated by blowing pressurized air into the inside of the extruded molten film to form a stretched cylindrical heat-shrinkable film 8. It is folded with rollers 8 and wounded on a winding roller 5 for storage. A photosensitive layer formed on an aluminum cylinder is covered with this film and allowed to shrink by heating, thus forming a photosensitive body usable for >=100,000 cycles of copying operations without maintenance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image bearing member for holding an electrostatic or toner image.

Electrostatic or toner images are formed by various electrophotographic processes. Image holding members that hold formed images include image holding members that have a photoconductive layer and are called electrophotographic photoreceptors, and image holding members that do not have a photoconductive layer.

Electrophotographic photoreceptors have various configurations depending on the type of electrophotographic process to which they are applied. Typical electrophotographic photoreceptors include photoreceptors in which a photoconductive layer is formed on a support, and photoreceptors in which a photoconductive layer and its insulating layer are laminated as an image-retaining layer. It is being In photoreceptors equipped with an insulating layer, this insulating layer is provided for the purpose of protecting the photoconductive layer, improving the mechanical strength of the photoreceptor, improving dark decay characteristics, or adapting to a specific electrophotographic process. Typical examples of photoreceptors having such insulating layers or electrophotographic processes using such photoreceptors include, for example, U.S. Pat. No. 2,860,048, Japanese Patent Publication No. 16429/1980, Tokuko Sho 38-15446
Publication No. 46-3713, Special Publication No. 42-2
It is described in Japanese Patent Publication No. 3910, Japanese Patent Publication No. 43-24748, Japanese Patent Publication No. 19747-1974, Japanese Patent Publication No. 4121-1972, etc.2.

A predetermined electrophotographic process is applied to the electrophotographic photoreceptor to form an electrostatic image, and this electrostatic image is developed and visualized.

Some representative image bearing members that do not have photoconductive layers are described next.

(1) For example, Japanese Patent Publication No. 32-7115, Japanese Patent Publication No. 3
As described in Japanese Patent Publication No. 2-8204 and Japanese Patent Publication No. 43-1559, an electrostatic image formed on an electrophotographic photoreceptor is coated with a photoconductive layer for the purpose of improving the repeatability of the electrophotographic photoreceptor. The toner image is transferred to an unsupported image holding member and developed, and then the toner image is transferred to a recording medium. An image holding member used in this electrophotographic process. (2) In addition, as another electrophotographic process in which an electrostatic image is formed on an image holding member without a photoconductive layer in correspondence with an electrostatic image formed on an electrophotographic photoreceptor, for example, Japanese Patent Publication No. 45-30320 As described in Japanese Patent Publication No. 48-5063, Japanese Unexamined Patent Publication No. 51-341, etc., a screen-shaped electrophotographic photoreceptor having a large number of minute openings is statically exposed by a predetermined electrophotographic process. By forming an electric image and performing corona charging treatment on an image holding member without a photoconductive layer via this electrostatic image, the ion flow of the cycorona is modulated to transform the electrostatic image into an image without a photoconductive layer. An example of this process is to form the image on a holding member, develop it with toner, and transfer it to a recording medium to form the final image. These include image holding members used in this electrophotographic process.

Image holding members used in electrophotographic devices are used for charging, developing,
Since it is subjected to electrical and mechanical processing such as transfer and cleaning, it must have characteristics that are compatible with the processing. Moreover, it is strongly desired that the properties last and are durable. In particular, in practical use, protrusions generated on the image holding member cause dielectric breakdown due to concentration of corona discharge, and the entire image is severely damaged.

These protrusions are dirt contained in the lower layer, photoconductive layer, image holding member, defective parts, etc., and it is extremely difficult to completely remove them in normal seamless image holding part manufacturing. It is difficult to

Further, in a coated seamless image holding member, when the photoconductive layer is a dispersed type, a sealing layer is required, and in order to overcome the above-mentioned drawbacks, the image holding member is required to be coated multiple times.

As an image holding member 7 that does not require such multiple coatings, there is an image holding member using a cylindrical heat-shrinkable film.

A cylindrical heat-shrinkable film is a cylindrical film that shrinks when heated, and by placing the cylindrical heat-shrinkable film over a specified article and heating it, a coating that adheres to the surface shape of the article is formed. It is. As described above, by using a cylindrical heat-shrinkable film, it is possible to cover the surface by heating only and in a short time, and therefore, the cylindrical heat-shrinkable film is widely used for various packaging applications.

The cylindrical heat-shrinkable film is made of a thermoplastic resin such as polyethylene, polypropylene, polyester, etc., and is formed into a cylindrical shape by a known inflation method.

By the way, when a cylindrical heat-shrinkable film is used as an image holding member, polyester resin is used from the viewpoint of electrical properties and durability. However, even with polyester films, rubbing scratches and toner fusion occur as the film is subjected to durability. (Rubbing scratches are caused by cleaning.
There are fine scratches in the circumferential direction. ) An object of the present invention is to provide an image holding member made by heat-shrinking a cylindrical heat-shrinkable film that has few scratches and toner fusion strength and has excellent electrical properties and mechanical strength.

The present invention provides an electrostatic image or toner ii! The image holding member has a surface layer for holding an image, and the image holding member is characterized in that the surface layer is made by heat shrinking a cylindrical heat shrinkable film made of polychlorotrifluoroethylene.

The polychlorotrifluoroethylene used in the present invention is
Both melting point and melt viscosity are lower than polytetrafluoroethylene. Therefore, with polytetrafluoroethylene, it is impossible to manufacture a cylindrical heat-shrinkable film by the inflation method, but with polychlorotrifluoroethylene, it is possible to manufacture a cylindrical heat-shrinkable film.

Furthermore, like polytetrafluoroethylene, it has a low coefficient of friction, is non-adhesive, and has excellent electrical properties V', so it has excellent properties as an image holding member.

The thickness of the cylindrical heat shrinkable film is generally 5 to 1
00 μm1 When used as an insulating layer of an electrophotographic photoreceptor, the thickness is 15 to 50 μm.

However, the following lubricants may be added as necessary. Zinc stearate, calcium stearate, butyl stearate, stearic acid monoglyceride, oleic acid monoglyceride, linoleic acid monoglyceride, ricinoleic acid monoglyceride, stearic acid amide, methylene bis stearamide, ethylene bis stearamide, etc.

The figure is a typical example of the method for producing a cylindrical heat-shrinkable film of the present invention.

The raw resin 1 is supplied to a hopper 6 and then thermally melted. The melted raw material resin advances in the direction of arrow 7 and is extruded from the circular mold part 2. Then, in order to stretch the extruded cylindrical film, compressed air is supplied from the inlet section 3. The raw material resin that has been melted by heating is extruded from the circular mold part 2, rolled up upward, and stretched at the same time by introducing compressed air to form a cylindrical heat-shrinkable resin. The film 8 is folded by a roller 4 and stored by a take-up roller 5.

Example: 100 parts of CdS powder (the following parts by weight) K was mixed with acrylic resin (part name: Dianal LR-63) as a binder.
7. Mitsubishi Rayon @ 10 parts and an appropriate amount of toluene as a diluent were added, stirred thoroughly, and then passed through a roll mill device with an 80 μm gap for dispersion. This paint was diluted with toluene to adjust the viscosity to 300 cps, and in this
Immerse a mmφ At cylinder to lOcm/min
pulled up at a speed of This was dried at 100°C for 20 minutes to obtain a photosensitive layer with a thickness of 40 μm.

Next, using polychlorotrifluoroethylene (trade name: Daiflon M270P, manufactured by Daikin Industries) as a raw material,
Cover with a cylindrical heat-shrinkable film of 84 mm diameter manufactured by the inflation method. Using a hot air circulation drying oven, 1
Heat shrinkage is performed at 20° C. for 20 minutes to form an insulating layer of 25 μm.

Comparative Example A photoreceptor made in the same manner as in Example 1, except that DK polyethylene terephthalate resin was used instead of polychlorotrifluoroethylene resin.

These photoreceptors can be used in an annual copier (Canon rNP-3).
00RJ), and image printing was performed under normal conditions.

As described above, in a photoreceptor using a heat-shrinkable polyester film, the surface insulating layer needs to be polished after 20,000 to 30,000 sheets are printed. On the other hand, a photoconductor using a heat-shrinkable film made of polychlorotrifluoroethylene resin requires no maintenance and
1L with more than 10,000 pieces of Mitsuru Ichida's axis

[Brief explanation of the drawing]

The figure is an explanatory diagram of a method for manufacturing a cylindrical heat-shrinkable film using an inflation method. The code 1 is the raw resin, 2 is the circular mold part, 3 is the pressurized air supply part, 4 is the roller, 5 is the take-up roller, and 6 is the hot (-). Patent applicant Canon Co., Ltd. agent Patent attorney Yu Kano

Claims (1)

[Claims] (1) An image holding member having a surface layer that holds an electrostatic image or a toner image, wherein the surface layer is made of a heat-shrinkable cylindrical heat-shrinkable film made of polychlorotrifluoroethylene. Holding member.