JPS603638A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain superior mechanical strength, to lower residual potential, and to improve transparency, humidity resistance, and durability by dispersing a powder contg. particles each contg. both of tin oxide and antimony oxide into a binder resin of polyurethane to form a surface protective layer. CONSTITUTION:A powder contg. particles each contg. both of tin oxide and antimony oxide is dispersed into a binder resin of polyurethane to form a surface protective layer on the surface of a photosensitive body. Since such a protective layer uses polyurethane as a binder resin, it is superior in mechanical strength. Since the powder contg. both of tin oxide and antimony oxide in each of the same particles is dispersed into the binder resin, the obtained photosensitive body is low in residual potential, superior in transpareny, mechanical strength, and humidity resistane, especially excellent in durability.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a quadriphotographic photoreceptor, particularly an electrophotographic photoreceptor having a protective layer.

Conventional technology Electrophotographic photoreceptors have photosensitive layers such as vapor-deposited films of Se or Se alloys, coating films in which inorganic particles such as ZnO or CdS, and organic pigments such as azo pigments and cyanine pigments are dispersed in bound resin. is provided on a support, and is used in an electrophotographic method in which an electrostatic latent image is formed by charging and exposure, and after development, the toner image is transferred to transfer paper, and then fixed to obtain an object. be.

However, such a photoreceptor having an exposed photosensitive layer on its surface has been subject to scratches on the surface or clogging of toner during handling, thereby shortening the life of the photoreceptor. In order to overcome this drawback, conventional attempts have been made to provide a surface layer different from the photosensitive layer on the surface of the photoreceptor. As surface layers, seven are insulating layers and the other is a protective layer.

The former insulating layer is a film made of electrically insulating resin, etc., provided on the surface of the photoreceptor, and is charged by -order charging → reverse polarity secondary charging → image exposure or primary charging → reverse polarity secondary charging and simultaneous imaging. An l# latent image is formed by the so-called NP method of exposure→uniform exposure. Although the photoreceptor having this insulating layer has the advantage that the insulating layer can be made thicker and has higher mechanical strength, it is necessary to use a special latent image forming process as described above. It has the disadvantage of being heavy at the end.

The latter protective layer is a layer having a lower resistance than the insulating layer, and forms an electrostatic latent image using the so-called Carlson method of charging→image R/D light. Although a latent image can be formed on a photoreceptor having this deep protection layer by the Carlson method, the residual potential is high, and the layer is thinner than the extinction layer, so the mechanical strength is inferior. Furthermore, the protective layers that have been tried in the past have had a resistance that is easily affected by humidity (which causes a change in charging potential).

Therefore, the conventional protective layer is one in which metal oxide powder containing tin oxide and antimony oxide (hereinafter referred to as tin oxide/antimony oxide powder) is dispersed in bound skin oil. Further, as the binder resin, for example, polyester, polystyrene, polyvinyl chloride, acrylic O cat fat, polycarbonate crumble, silicone resin, etc. are used.

However, when a photoreceptor having a protective layer formed using these resins on its surface is used in a copying machine, it has been found that the protective layer is insufficient in terms of mechanical strength.

Purpose of invention An object of the present invention is to have a fatigue retaining layer with excellent mechanical strength.

It is an object of the present invention to provide a photoreceptor for photosensitive photography.

Structure of the Invention What is the present invention? It is characterized in that a protective layer in which powder containing tin oxide and antimony oxide in particles is dispersed is provided on the surface of the photoreceptor using Refletan as a binder.

Above i? +J urethane has a combination strength with active hydrogen (for example, A, >, A1., A/l/ :I-/L/,
It is preferable to use a +2 Fiiξ type polymeric resin compound which forms a urethane bond by three-dimensionally crosslinking and curing a compound having an isocyanate group (7enol, thiol) and a compound having an isocyanate group.

The powder containing tin oxide and antimony oxide in the same particle is preferably a solid solution or a fused body, and has an average particle size in the range of 0.03 to 03 μm. Furthermore, the proportion of this powder in the a-reservoir layer is 10 to 60.
Weight percent is preferred.

Further, the thickness of the protective film is preferably 1 to 30 μm, and various additives may be added to the protective layer to improve dispersibility, adhesion, or smoothness.

This V! The film is attached to the photosensitive layer by applying a solution containing tin oxide/antimony oxide powder in a binder or by forming it into a film and then adhering it.

Roughly photosensitive j sounds include Ss or Se, Te, and A.
Alloy with s, etc.; ZnO, CdS, CdS Ss
Dispersed inorganic particles such as in binder M Ij &; polyvinylcarbazolium salt and 4C! An organic photosensitive material such as a eutectic complex with recarbonate is used. The photosensitive layer 1'J may be a single layer, a laminate of two or more layers such as a laminate of a charge generation layer and a charge transport layer, or a laminate of photosensitive layers having different absorption wavelength regions.

Furthermore, an intermediate layer may be provided between the protective layer and the photosensitive layer. This intermediate layer is an adhesive layer that enhances the adhesion between the photosensitive layer and the photosensitive layer, and a charge injection blocking layer that stops the electrical charge at the interface between the retention layer and the photosensitive layer. Various organic polymer compounds such as polyester/l/resin, polyamide resin, polystyrene resin, polyvinylidene chloride resin, polyvinyl acetate, divinyl chloride, acrylic resin, silicone resin, fluorocarbon resin, etc. or trimethylmonomethoxysilane , r-glycidoxypropyltrimethoxysilane,
Silane cassilling agents such as γ-methacryloxypropyltrimethoxysilane; Metal alkoxides such as titanium tetrabutoxide, aluminum trizoloxide, zirmiconylam titratoxide; titanium acetylacetonate, zolconium acetylacetonate A polymer compound formed from a metal acetylacetone lead body such as the following can be used. The thickness of this intermediate layer is /θμm or less, preferably 73m or less.

As the support for the photosensitive layer, metals such as aluminum, nickel, and stainless steel, plastic sheets or glass having a conductive film, paper treated with 4-conductivity, and the like can be used.

Effects of the Invention According to the present invention, since polyurethane is used as the binder resin for warranty 1'ti, it is particularly excellent in terms of mechanical strength. In addition, powder containing tin oxide and antimony oxide in the same particles is dispersed in the binder resin, resulting in lower residual potential, transparency, mechanical properties, and iJ resistance compared to conventional protective layers.
It is excellent in properties that should be satisfied as a protective layer of an electrophotographic photoreceptor, such as properties, and a photoreceptor with particularly good durability can be obtained.

Example Next, examples of the present invention will be described while comparing them with comparative examples.

(1) Comparative example AS2Se, alloy vapor deposited film (Aθ
7 parts by weight of zirconium tetrabutoxide (Matsumoto Kosho Co., Ltd. gzA Otsu0), γ-acryloxyglobyltrimethoxysilane (KBM, manufactured by Shin-Etsu Chemical Co., Ltd., l-θ
3) A solution consisting of 7 parts by weight and 20 parts by weight of 0-butanol was applied by dip coating and dried in a Hiro θC for 2 hours to produce a photoreceptor having a strip layer with a thickness of θS μm. Next, a solution prepared by dispersing polycarbonate S* part and 33 parts by weight of tin oxide/antimony oxide powder together with methylene chloride and cyclohexanone solvent in a ball mill was applied and dried to form a protective layer having a thickness of about 10 μm. When I made copies using this photoreceptor, I was able to obtain clear images. but,
Using this photoconductor, copies were made continuously using a copying machine equipped with a grade cleaning device and a paper stripper (14 claws on one side that are in constant pressure contact with the photoconductor). From around , / 0.0θ0 copies, black streaks began to appear on 7, , = -, which corresponds to the part of the peeling claw, and there was a tendency for the photoreceptor to gradually become thicker and become 1. When the photoreceptor was removed from the copying machine and observed, the protective layer was visible. The photoreceptor was placed in the copying machine again, and after the copy was readable up to /θa00θ, the thickness of the protective layer excluding the peeled nail portion was measured. It was as worn out as it was.

(11) Actual Lm Example/Comparative Example/Acrylic material on As2Se3 alloy photoreceptor with intermediate IN of 03 μm thickness obtained by the same method as in Comparative Example/ Lior (1 rethane made by Kawanishi Paint Co., Ltd.) Otsu θ superimposed part, solvent (rethane thinner made by Kansai Paint Co., Ltd.) //; After dispersing and mixing, a solution containing 9 parts by weight of a curing agent was applied and dried to form a protective layer with a thickness of about 70 μm. The composition ratio was such that the weight ratio of the reef-preserving resin and the tin oxide/antimony oxide powder was 63:33 after drying. When a test similar to the ratio 1 bite example/ was performed on a photoconductor with this protective Q JJ, good images were continuously obtained, and no scratches were observed on the protective layer even after copying/00.00θ. Ta. Table 1 shows the performance and amount of abrasion of this chisel light body, and there was almost no abrasion on one wall.

(Ill) Obtained in the same manner as Example/Comparative Example/. An acrylic polyol (Acrydic Agθg manufactured by Dainippon Ink Co., Ltd.
) 3 parts by weight, 7 parts by weight of tin oxide/antimony powder, 73 parts by weight of tin oxide/antimony powder, dispersed and mixed in a &-lumil, and then mixed with a hardening agent (Parnock D- 73θ) A solution containing Hiroshigeharube was applied and dried to form a protective layer with a thickness of about IO μm. In this case, Example/
Similarly, the weight ratio of the resin to the tin oxide/antimony oxide powder is Aj73k. With this protection IS1, it was possible to continuously obtain good images with the photoreceptor (as in Example/). Its various performances are shown in Table/.

(1v) Example 3 A polyester polymer was applied onto an As2Se3 alloy photoreceptor having an intermediate JV with a thickness of θ3 μm obtained in the same manner as in Comparative Example. J O”
Parts by weight of methylene chloride 112-trictetraloethane (/:/)/, parts by weight of tin oxide/antimony oxide powder were placed in a ball mill and dispersed and mixed.
A solution containing 7 parts of isocyanate (Conquaternate HL manufactured by Sumitomo Bayer Urethane) was applied and dried to form a protective layer with a thickness of about 10 μm. In this case as well, the weight ratio of the resin and the tin oxide/antimony oxide powder is A
j:, 3k. The No. 13 phosphor having this protective layer was also able to continuously obtain good images in the same manner as in Example 1, as shown in the e fi stirring performance table.

(V) Moisture-curable urethane paint resin (Orestar Mgθ-40CX manufactured by Mitsui Toatsu Co., Ltd.) 63 on an As2Se alloy photoreceptor with an intermediate layer of a 5 μm thickness obtained in the same manner as in Example/Hiro Comparative Example/
Part by weight, cellosolve acetate xylene (/:/)2/
77 parts by weight of tin oxide/antimony oxide powder were placed in a ball mill, a dispersed and mixed solution was applied and dried to form a protective layer with a thickness of about 10 tm. In this case as well, the weight ratio of M fat and donated body tin/Hψ antimony powder was blended to Otsu 383S, as in Example. The photoreceptor having this photoreceptor layer was also able to continuously produce good images in the same manner as in Examples. Various characteristics ri are shown in Table/.

As can be seen from the table, the examples of the present invention are not much different in terms of electrostatic properties and image characteristics than the comparative examples, but they are significantly inferior in terms of durability.

Claims (1)

[Claims] In an electrophotographic photoreceptor having a transparent protective layer on its surface,
An electrophotographic photoreceptor characterized in that the protective layer is made of a powder containing tin oxide and antimony oxide dispersed in a binder fat, and the binder fat is polyurethane.