JPS61261759A - Frictional electrostatic charging member for one-component type toner - Google Patents

Abstract

PURPOSE:To charge electrostatically and stably a toner to a prescribed polarity and to make possible the formation of a uniform toner layer by forming a frictional electrostatic charging body of a rubber compd. contg. an electrostatic charge controlling agent applying the electrostatic charge of the polarity reverse from the polarity of en electrostatic latent image and having a prescribed loss coefft. CONSTITUTION:The frictional electrostatic charging body 14 consists basically of the rubber into which the charge controlling agent is incorporated. More specifically, an electron acceptive functional group-contg. azo compd. which charges the toner to the positive polarity is used when the electrostatic charge image is negative and a quaternary ammonium salt or the like which charges the toner to a negative polarity is used if the electrostatic latent image is positive. The loss coefft. of the body 14 is made <=0.1 within a 10-100Hz range, because the generation of a suitable high-frequency oscillation is not possible if the loss coefft. exceeds 0.1. The toner is stably charged to the prescribed polarity and the formation of the uniform toner layer is made possible by using such body 14.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a one-component toner friction charging member used in electrophotography, electrostatic recording, electrostatic printing, etc.

(Conventional technique?) Conventionally, as a developing method for electrostatic latent particles formed on a cylindrical image support such as an electrophotographic photoreceptor or an electrostatic recording medium, magnetic or non-magnetic one-component toner is used. Used as a developer NJ agent, this developer burst 1 is used to form an electrostatic latent image through a corona discharge path (a type in which the electrostatic latent image is completely developed by applying it to a V property).
Corona #electric type).

Alternatively, the friction between the developing roller (charged toner carrier) and the preliminary image side, which are arranged with a predetermined gap with respect to the image support, or the charging caused by a rotating rod placed in pressure contact with the developing roller 1, 7. There is a known type (friction zone type) that develops an electrostatic latent image by applying a charge of opposite polarity to the electrostatic latent image to the current abrasive material by rubbing between the member and the developing abrasive material. It is being

7. Toner is a particle powder made by mixing natural or synthetic resin with colorants such as dyes and additives, and its composition is determined by taking into account all development characteristics. Divine ingenuity is being used, for example, to impart all the electrostatic charge of a predetermined polarity to the toner.

Using a colorant that also has a charge control function,
Alternatively, compositional innovations have been made, such as mixing a charge control agent in addition to the colorant.

(Problem to be solved by the invention) However, the conventional present number method in the upper box has the following problems: ','
: , ``There is a problem''・i.

(In corona discharge type development method, floating □”
The toner attached to the corona discharge wire deteriorates the charging characteristics, making it impossible to obtain the desired development characteristics.

・I-zta. In the triboelectric type development method, there are problems in that the toner is expensive due to improvements in the donor composition, and it is difficult to obtain clear colors in color development due to compositional constraints.

5..1 When trying to cope with color development, there is a problem that the charging characteristics of the toner;l are not sufficient.

, 1. ＊“′”″”°°”′″″°6”′″1゛1′″
'1, which stabilizes the toner to a predetermined polarity.
':', J −' (K fJi with charging 1
*o--y upper 1 or 6 charging": To provide a 1-branch toner triboelectric charging member that forms a uniform toner layer and exhibits all the excellent development characteristics that can be applied to color development. purpose.

(Solution F?) A friction band imager that contacts and rubs the toner to impart an electrostatic charge of a predetermined polarity to the toner.

The feature of the tribo-charging member of the present invention, which is comprised of a support for supporting the tribo-charging body, is that the tribo-charging body carries an electrostatic charge of opposite polarity to the electrostatic latent image formed on the (F4J image support). The reason is that it is made of a rubber compound that contains a charge control agent that can be imparted and has a loss coefficient value of 0.1J or less in the range of 10 to 100 Hz.

For the base material of the triboelectric charger, natural rubber, synthetic rubber, or a mixture of these rubbers is used, and in particular, ethylene propylene rubber (EPl'L), ethylene propylene diene rubber (
EPnM) and silicone rubber (SR) are preferable in consideration of charging characteristics, photosensitive material contamination resistance, ozone resistance, and the like.

l! As a charge control agent contained in rubber, which is a heavily charged body material, the electrostatic latent image formed on the image support is f.
(In other cases, an azo thread compound containing an electron-accepting functional group that can be charged entirely by a toner with positive polarity is used.) If the electrostatic latent image formed on the image support is of positive polarity, A quaternary ammonium salt or the like is used, which can charge the toner negatively.

,1. 1 As an electron-accepting functional group-containing azo thread compound.

(2) An azo compound containing a chlorine group and/or a nitro group classified into Color Index Pigment Yellow 3.14°110 and Pigment Orange 13 is used.

In addition to the above configuration, the triboelectrically charged body of the present invention further has a limited value of the loss coefficient l.
FFgayot41. Ah, *a, 62. . (, 1st
""9"・"-"'l"lK"t, **m*'1ix
n: Applying an electrostatic charge of a predetermined polarity to the toner! ' Ka, ft, L,! 4, 7>,
As the developing roller rotates, the charged toner passes smoothly between the 4 bands □ □ □ and □, □ developing roller, forming a uniform layer of charged toner on the developing roller to obtain the desired development characteristics. Seshi, 1 15.・ I can do things. As mentioned above, the loss k coefficient l of the triboelectric body is determined in the operating temperature range (10
If it is 0.1 or less within one range of 10 to 100
"Aec) High-frequency micro-vibration is generated in the frictionally charged body, and the large particle size components or aggregates of the toner smoothly pass between the frictionally charged body and the developing roller, and a single layer of charged toner is uniformly formed on the developing roller. When the value of the friction coefficient 1 of 0.1 gold exceeds 0.1 gold, vibration damping performance is exhibited, and the above-mentioned toner can pass through smoothly.
It is desirable to achieve the intended purpose without generating high-frequency micro-vibrations suitable for vibrations.

In the present invention, in addition to the above-mentioned predetermined charge control agent, the rubber material forming the triboelectric charger is added.

Various fillers commonly used as rubber compounding agents.

Reinforcing agents, softeners, processing aids, vulcanizing agents, vulcanization accelerators, etc. are used as appropriate.

(Example) The present invention will be explained below based on nine drawings.

FIG. 1 is a diagram showing an example of the triboelectric charging member of the present invention,
FIG. 2 is a schematic diagram showing an example in which this is applied to a developing device.

The triboelectric charging member (10) of the present invention includes a gold-flexible support (12).
), the rubber friction band member (14) is fully fixed and the construction is completed.

The developing roller (20) is placed in pressure contact with the developing roller (20), which is placed 71 on the image support (30) with a predetermined gap maintained therebetween. 17. Inside the hopper (40) is one-component toner (50
) is stored in the hopper (4), and this toner (50) is stored in the hopper (4).
0) The developing roller (20) is supplied from the bottom to the phase 5.
As the developing roller (20) rotates (in the direction of the arrow), frictional charging occurs between the toner (50) and the frictional charging member (14), and a predetermined o charge is applied to the toner (50). The charged toner (50) smoothly passes between the frictionally charged body (14) and the developing roller (20) due to the high frequency wave generated in the frictionally charged body (14), and the developing roller (
20) The uniformly charged toner is formed into a single layer on the surface of the developing roller (20) while being held at a predetermined f.
A is transported at image position O. Then, the developing roller (
20) The charged 1-ner (50) on the top flies against the electrostatic latent image formed on the surface of the image support (30) advancing in the direction of the arrow, and the electrostatic The latent image is developed. The above-mentioned toner (50) flies off the developing roller (20).
) and the image support (30), which is applied based on Shizukuta.

Next, two specific examples of the triboelectric charging member of the present invention will be shown.

Triboelectrically charged material (J￥saT, (1
mm x width 200mm x thickness 2mm)k Vulcanization molding.

Stainless steel thin plate support (length 20mm x width 20Q m)
1n x thickness 1.12ff1m) to produce a triboelectric charging member as shown in FIG.

Attach the frictional charging part as shown in FIG. 2, and use the styrene-methyl methacrylate copolymer tree 11 as a one-component toner by mixing a coloring agent that does not have a charge control function. The electrostatic latent image on the image support was developed L7 to obtain a copy. The results are also listed in Table 1.

In addition, as a developing roller, N1 volume resistivity lXl011Ω
・cm phenolic resin coated roller (outer diameter 15m〃lφ
), and the rotational speed during operation was set to 1100 tn/sec. Further, the frictional charging member was aligned with the developing roller and pressed against the pressing surface in the curved direction with a pressing force of 200 mm/gate width.

As is clear from the results in Table 1, the predetermined charging control uniformity 1
1 (Comparative Example 1), or 1rr (Comparative Example 2) which does not have the specified loss coefficient property.
(i) has a defect in either the charging property or the toner single-layer forming property and cannot obtain good copying properties; Examples 1 to 3).

Excellent charging characteristics and toner layer forming characteristics, and copying characteristics of 39'' were obtained.

Note 2) Toshi 8H851U (manufactured by Toshin Ricon, containing silica) Note 8) Sofunon 105F (manufactured by Toho Chemical Industries) Note 4) ○
(Good charging) X (Poor WI charging) Note 5) ○ (Good layer formation) x (Poor layer formation) 1. (Effects of the Invention) As explained above, according to the triboelectric charging member of the present invention,
The triboelectric charger is formed of a rubber compound containing a charge control agent capable of imparting an electrostatic charge of opposite polarity to that of the electrostatic latent image formed on the image support and having a predetermined loss coefficient value. Therefore, the toner can obtain stable charging characteristics due to friction with the triboelectrically charged body. At the same time, the charged toner can smoothly move between the triboelectrically charged body and the developing roller based on moderate high frequency vibrations generated in the triboelectrically charged body. The toner passes through the developing roller to form a uniform layer of charged toner on the developing roller, resulting in excellent copying characteristics.

, i 47'c・The present invention K, t h"・
There is no need to mix a separate charge control agent in addition to a functional colorant or a single colorant, and to obtain the desired copy color. By mixing only the colorant, the degree of freedom in toner formulation design increases, and clear color copies can be stably obtained.

Furthermore, according to the present invention, the desired clear copying characteristics can be obtained by simply incorporating a small amount of the charge control agent into the triboelectric charger instead of mixing it into the toner that is consumed each time a copy is made. You can also try to get down.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the triboelectric charging member of the present invention, and FIG. 2 is a schematic sectional view of essential parts showing an example of a developing device to which the same is applied. 10: Frictional charging member 12: Support body. 14: Reed friction charged body, 20: Current roller. 30: Image support, 40: Honopa 50: Toner patent owner

Claims (1)

[Claims] (1) It is pressed against the surface of a developing roller arranged with a predetermined gap with respect to the image support, and the one-component toner supplied onto the developing roller contacts and rubs the one-component toner.
A tribo-charging member comprising a tribo-charging member that imparts an electrostatic charge of a predetermined polarity to component-based toner and a support that supports the tribo-charging member, wherein the tribo-charging member is attached to an electrostatic latent formed on an image support. A one-component toner characterized by being formed from a rubber compound containing a charge control agent capable of imparting an electrostatic charge of opposite polarity to that of an image and having a loss coefficient value of 0.1 or less at 10 to 100 Hz. Frictional charging member.