JPS5872148A - Electrostatic recording body - Google Patents

Abstract

PURPOSE:To reduce the abrasion and heat generation of a dielectric layer and to obtain a good image by preventing the generation of toner filming, by incorporating heat resistant lubricant-liquid having critical surface tension below the specific value into a dielectric layer having ruggedness on its surface, on a conductive supporting body. CONSTITUTION:A conductive layer 1 is provided on a supporting body 2 such as polyester film, and thereon solid particles (ZrO2, rigid ceramic etc.) 4 are dispersed into a bonding resin 5 to form a dielectric layer 3 having 5mu-10-oddmu ruggedness. At the time of forming this layer 3, dielectric layer forming liquid to which temperature resistant lubricant liquid such as silicone oil and fluorinated oil having <=50 dyne/cm critical surface tension is added, is applied and dried to form said layer 3. By this way, the generation of <= several mu small ruggedness is prevented at the time of forming the layer 3, and the abrasion and heat generation owing to contact of the layer 3 with recording pointer are suppressed and the durability is improved, and a clear image without toner filming is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an electrostatic recording material in which a Wsw layer is provided on a conductive substrate.

In recent years, with the increase in the amount of information, and social imperatives such as resource saving, labor saving, and pollution-free, various recording methods have been put into practical use and improved in the information recording field. Among them, electrostatic The recording method is as follows: ■) The image signal forming means is inexpensive and simple.

官) Plain paper can be used as the recording paper, reducing the cost of recording paper. ■) The latent image recording section uses solid-state electronic scanning and has excellent resolution, and the printing speed is extremely fast at Psec/dat. It has the characteristics of

Next, to record the regret using the electrostatic recording method, for example, 1
) Irradiate the electrostatic recording medium with an ion stream in a pattern or scan with a stylus (recording needle); 2) Apply the electrostatic latent pattern formed on the electrophotographic photoreceptor onto the electrostatic recording medium. After the latent image is transferred, it is visualized by developing it with an electroscopic developer.

These conventional image recording methods (particularly 1 above) can be seen from a different perspective, employing various means such as a scanning type with movable parts, a fixed recording head with multiple needles, an air gap discharge type, and a rear control type. It is connected to what can be done.

In addition, conventionally, the latent image formed on the dielectric recording layer by the above-mentioned recording method is transferred to an electroscopic developer (electroscopic toner).
In many cases, the toner was developed with a thermosetting toner and the toner was fixed as is, but recently, the electrodetectable toner is transferred to other transfer materials (e.g. paper, cloth, synthetic paper, etc.) and this is fixed. 1! A recording method that allows the recording material to be used repeatedly, that is, a transfer electrostatic recording method, has come to be adopted, and the recording material of the present invention can be used in this method. It is something.

An electrostatic latent image is formed by causing a discharge between the stylus and the dielectric layer of the recording medium. For this purpose, a voltage higher than the Paschen discharge firing voltage curve must be applied to the stylus, and the stylus and If the gap in the dielectric layer is too small, the voltage required to start a discharge will rise rapidly, making it difficult to discharge. On the other hand, if the gap is too large, the voltage required to start the discharge will increase, making it difficult to discharge, causing dot diffusion, and degrading the decomposition. In this way, in discharge,
It is highly dependent on the air gap between the stylus and the dielectric layer.
It has been extremely difficult to accurately control the gap spacing on the μ order.

In conventional transfer-type electrostatic recording materials, the gap distance was managed mechanically using a smooth surface dielectric t1-, but the gap distance maintaining machine was expensive, unreliable, and difficult to maintain. It wasn't. Therefore, by forming unevenness on the surface of the recording medium and bringing the recording electrode into contact with this, a gap between the recording medium and the recording medium is secured under the recording electrode where discharge is most likely to occur due to the unevenness of the surface of the recording medium. Discharging and forming charge latent scratches has been performed mainly on electrostatic recording materials.

Generally, solid particles are dispersed in the dielectric layer resin.
Discharge gap irregularities of approximately several pm to 5 μm are formed.

However, conventionally, in the process of coating a dielectric layer dispersion on a support and drying and curing, the surface temperature of the dielectric layer decreases as the solvent in the dispersion evaporates, and the density increases due to further concentration. The convection current was 6 degrees, and as a result, an orange peel and deaeration hole irregularities of about 0.1 to several μm were formed, which were smaller than the irregularities necessary for the discharge gap as described above.

These small irregularities cause toner fill 2,
This becomes a big problem especially when the recording medium is used repeatedly.
This resulted in an increase in the background density of the plain paper (transfer paper), that is, a decrease in the clarity of the recording.

Furthermore, in conventional recording media, the coefficient of static friction on the surface is large, so it is easy to cause heat generation at the contact area of the stylus. Therefore, the inventor of the present invention has repeatedly investigated the problem in order to solve the above problem. , defended the invention.

That is, the transfer type electrostatic recording material of the present invention is provided with a dielectric layer having an uneven surface on a conductive support, and a heat-resistant lubricant liquid having a critical surface tension of 50 dyne/m or less is contained in the dielectric layer. It is characterized by the addition of wood grains.

By adding a heat-resistant lubricating liquid (silicone oil, fluorinated oil, etc.) with a critical surface tension of 50 dyne/m or less to the dielectric layer forming solution, the small irregularities mentioned above are eliminated and the dielectric surface becomes low. Since B is covered with a thin film of surface energy liquid, the surface energy decreases, mold releasability increases, and toner filming becomes less likely to occur.

In addition, the stable dispersion liquid migrates in the dielectric layer, so even if the oil on the surface is gone, it will gradually seep out from below, reducing wear and heat generation at the contact part of the stylus. I also work. However, if the critical surface tension of the heat-resistant lubricant liquid is 50 dyne 7 cm or more, it is difficult to obtain the above-mentioned effects.

To actually produce a recording medium, for example, as shown in FIG. 1, solid particles 4 ( Disperse zirconia oxide, titanium oxide, hard ceramic material) in a binder resin 5 (modified urethane resin, modified silicone resin, etc.), apply a mold layer forming liquid to which a heat-resistant lubricating liquid is added, and dry. do it.

Next, in order to actually obtain a recorded image using the electrostatic recording material of the present invention, after forming an electrostatic latent image, it is necessary to develop and transfer it in the same manner as in the conventional electrophotographic method. The process is as shown in Figure 3. An image signal voltage is applied to an endless belt-shaped electrostatic recording medium 6 through a stylus electrode 7 to form an electrostatic latent image. This latent image is converted into toner by a developer unit 8 to obtain a toner image 9, and then transferred to plain paper 11, which is a transfer paper, by a transfer corona charger 10 to obtain a recorded image 12. Even after the transfer process, the toner adhering to the electrostatic recording medium 6 is removed by the cleaning roller 13.
Next, the static elimination roller 14 and the snow removal corona charger 1
5, the electrostatic recording medium 6 is used repeatedly.

The shape of the electrostatic recording medium is not particularly limited, but from the viewpoint of repeated use, an endless belt shape, a rigid drum shape, etc. are common.

Next, examples will be shown.

Example 1 Curzen-dispersed polyester resin was coated on a polyester film with a thickness of 100 pWL, and the surface electrical resistance was 8.
A 5 pm thick conductive layer of X 10'Ω6 was obtained.

Next, aluminum oxide powder (average particle size = 6.9 μm, 20 parts by weight J
= 7 pm) Agril polyol (Hitachi Chemical 15 parts by weight Hitaloid 3080) Silicone oil (critical surface tension 0.3 parts by weight 18
dyne 7cm: Shin-Etsu Silicone KF-96-1
00) The above composition was dispersed in a Zeel mill for 1 hour, and incyanate (5 parts by weight, Desmodur L-75, manufactured by Jern Co., Ltd.) was added and thoroughly stirred.

The dispersion obtained above was applied onto a conductive film by a blade coating method, and dried and cured at 1001:1 for 20 minutes to obtain an electrostatic recording material having a dielectric layer with a thickness of 18 μm.

Next, the stylus applied voltage was -350V and the segment voltage was +350V using a single-sided control type 8/■ multi-stylus electrode.
The surface potential was determined by recording the peta latent image at v -200
It was V.

Example 2 A comparative electrostatic recording medium was prepared in the same manner as in Example 1 except that the silicone oil was not added.

Next, using the recording medium of Example 1 and the comparative recording medium, the coefficient of static friction and critical surface tension were determined, and a latent image was continuously recorded on plain paper using the integrated process device shown in FIG. ,
Reflection density was determined.

The results are shown in Table 1 and Figure 3. (However, the critical surface tension is the value of each dielectric layer forming liquid6) From the results in Table 1 and above, it is clear that the recording medium of the present invention
There is almost no toner filming, very little coloration on the background, and extremely high clarity.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the structure of a recording medium of the present invention. FIG. 2 is a diagram showing an example of a comprehensive process apparatus applied to the recording medium of the present invention. FIG. 3 is a graph (curve) showing changes in reflection density with respect to the number of running sheets of plain paper. DESCRIPTION OF SYMBOLS 1... Conductive layer 2... Support 3... Dielectric 11 Shikawahedron particle 6... Recording body
7... Stylus electrode 8... Current unit)
11... Plain paper 13... Cleaning roller

Claims (1)

[Claims] 1. A heat-resistant lubricant liquid having a critical surface tension of 50 dyne/an or less is added to the dielectric layer of an electrostatic recording material for transfer type, which has a dielectric layer having an uneven surface on a conductive support. Characteristic electrostatic recording material for transfer type.