JPS63228170A - One component type toner - Google Patents

Abstract

PURPOSE:To enable development by the simultaneous method and image transfer to plain paper by the corona transfer method by using a one-component type toner containing silicon carbide and fine conductive particles dispersed into the inside of the toner particles made of an insulating resin as a base material. CONSTITUTION:The toner 1 is made of the insulating resin 5, such as usually used known thermoplastic resins, containing the silicon carbide powder 2 of <=1mum particle diameter, the conductive material 3, such as carbon black, to be used also as a black pigment, the magnetic material 4, preferably such as an Fe3O4 or iron alloy powder, and other additives dispersed into said resin 5, thus permitting the obtained toner to be changed in resistance by bias voltage, and to become a conductive toner developable by the simultaneous method in the case of being raised to certain designated voltage or above, and an insulating toner when the bias voltage is not applied and to be transferred to the plain paper by the corona transfer method or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to monocomponent toners used in electrophotography.

[Conventional technology]

In recent years, various printing devices using xerography technology have been put into practical use and used. To give an overview of the toners used in this technology, in the case of printing devices using the "Carlson process", insulating non-magnetic toners are used in the two-component magnetic brush development method and the float electrode effect consideration method (FEED method). In the case of electrofax, conductive Mi toner and the like are known.

Recently, a method of forming an image by simultaneously performing exposure and light consideration has been developed, which has the potential to greatly simplify the process.
(hereinafter referred to as the "simultaneous method") has been studied in various places, and has been proposed, for example, in Japanese Patent Laid-Open No. 153957/1983. In this method, a bias voltage is applied and a brush of highly conductive ata toner is applied to l! The surface f of the photoconductor during forward light is considered to be the most cost-effective method, and when the photoconductor acts as an insulator (unexposed area) and when it acts as a conductor. Therefore, a difference occurs in the amount of charge injected into the toner in contact with the photoconductor surface due to the bias voltage, and this difference in charge amount becomes a difference in electrostatic adhesion force to the photoconductor surface, making it possible to There is.

[Problem that the invention seeks to solve]

However, due to the conductivity of the toner used in the simultaneous method,
The well-known corona transfer method had the disadvantage that sufficient transfer to paper could not be achieved because the charge on the toner was neutralized in a short relaxation time, resulting in loss of residual charge and electrostatic adhesion to paper. .

An object of the present invention is to provide a toner that can be used in a simultaneous method and that can be transferred to plain paper by a corona transfer method.

c) Means for Solving Problems] The one-component toner of the present invention has silicon carbide and conductive fine particles dispersed inside the particles having an absolute Ik resin as a base material, and the toner contains a magnetic reference material. ft features.

[Effect]

According to the above configuration of the present invention, charge injection into the toner at the tip of the magnetic brush at the time of consideration in the simultaneous method depends on the bias voltage, and as the bias voltage increases, the resistance decreases and the amount of charge injection increases. I can do it.

Furthermore, during transfer, the resistance increases, and the charges injected by the bowl can generate electrostatic adhesion to a piece of paper.

[Implementation row]

FIG. 1 shows a cross-sectional view of a toner according to one embodiment of the present invention.The toner according to the present invention is made of silicon carbide powder2. Conductive agent 3. It has a structure made of an insulating resin 5 in which ai magnetic material and other additives are dispersed. Carbon black is used as the conductive agent 3, which also serves as a black pigment.

As the silicon carbide powder 2, it is preferable to use one having a particle size of LAtn or less.As the VB magnetic material, a known magnetic powder is used. It is preferable to use triiron tetroxide, r-ferric oxide, chromium dioxide, nickel 7-elite, iron alloy powder, etc. As the insulating resin 4, commonly used thermoplastic resins can be used. Desirably, polystyrene and copolymers thereof, polyester and copolymers thereof, polyethylene and copolymers thereof, epoxy resins, acrylate and methacrylate resins and copolymers,
Is it preferable to use vinyl resin etc. alone or in combination, and as other additives? M, 0.1 wt% to 0 kinetic improver (SzO, Too, etc.)
．． It is usually carried out using the above raw materials, which are preferably added in a range of 5tott4. A toner having a diameter of 10 to 15 μm is produced through the mixing, crushing, and classification steps.

FIG. 2 shows how the toner of the present invention is used in a simultaneous method, in which the same elements as in FIG. 1 are given the same numbers. When the photoreceptor 13, which includes the photoconductor layer 10, the transparent conductor layer 11, and the transparent support layer 12 stacked in this order, moves in the direction of the arrow 14, the photoreceptor 13
Receive 5. Due to the magnetic material dispersed in the resin, the well-known magnetic brush is formed using a magnetic roller 16 and a sleeve 17! >, II is in contact with the photoconductor layer 10 in the optical part.

A bias voltage 18 is applied to the sleeve 17, and by increasing the applied voltage, charge is injected into the toner in contact with the photoconductor layer, but the amount of injection is different between the exposed and unexposed areas. As a result, a difference is caused in the electrostatic adhesion force of the toner to the surface of the photoconductor layer 10, which is considered.

FIG. 3 shows how the toner of the present invention is transferred by the corona transfer method. In FIG. 1, the same elements as in FIG. 2 are given the same numbers. A transfer paper 19 is placed on the carefully considered surface of the photoreceptor 13, and ions with a polarity opposite to the surface charge of the insulating resin 5 of the toner i are injected from the back side of the transfer paper by a corona transfer device, and this electrostatic force is It acts as a transfer force and toner transfer is achieved.

[Implementation row l]

Acrylic resin (Delpet ωN, Asahi Kasei) as an insulating resin, carbon black (Su44.Mitsubishi Kasei) as a conductive agent, triiron tetroxide (Toda Kogyo) as an a-pillar material, and silicon carbide whiskers of 1 μm or less as a silicon carbide powder. The raw materials were weighed to give the composition shown in Table 1.

Thereafter, the mixture is roughly mixed and kneaded using a screw extruder. The mixed material is coarsely pulverized to 0.1 to 0.5 M using a stamp mill, and the coarsely pulverized material is further pulverized to 5 to 20 μm using a jet mill. The toner was further classified into 10 to 155 m using an air classifier to produce toner.

Table 1 Next, using the single-component toners of Samples 41 to 6, the % transfer and constant yIjr were performed by the simultaneous method, and the results are shown in Table 2.

Table 2 As is clear from Table 2, the phenomenon depends on the bias voltage,
The phenomenon could not be observed when the bias pressure was less than 2007. The preferred bias voltage is 2007-400v, 400v
When the number was 7 or higher, the life of the photoreceptor decreased.

[Comparison column l]

Using the same raw materials and manufacturing method as in Example 1, toners having the compositions shown in Table 3 were manufactured.

Table 3 Next, using the single-component toners of Samples 47 to 10, the phenomenon, transfer, and fixing were performed by the simultaneous method, and the results are shown in Table 4.

Table 4 As is clear from Table 4, when the silicon carbide content is less than 10 wt %, there is no voltage dependence of the amount of charge injection, and the amount of charge injection is determined by the content of the conductive agent.

Further, when the silicon carbide content was 30 wt or more, conductivity was exhibited regardless of the content of the conductive agent.

From the above, in order to obtain good fixing 11' by the simultaneous method, the silicon carbide content should be 10 to 30 wt%, the conductive agent content should be 1
~5 wt% is preferred.

[Run 2] A toner was produced using polyester (Pylon 200, Toyobo Co., Ltd.) as the insulating resin and in the same manner as in [Run 1] except that the composition is shown in Table 5.

Table 5 Next, the results of the phenomenon, transfer, and fixing performed by the simultaneous method using the single-component toner of Samples AI1-16 are shown in Table 6.
Shown below.

Table 6 As is clear from Table 6, development depends on the bias voltage,
Development could not be performed at a bias voltage of less than 200'7. The preferred bias voltage is 2007-400v, 40
At 0 V or more, the life of the photoreceptor decreased.

[Comparison row 2] Toners having the compositions shown in Table 7 were manufactured using the same manufacturing method as in actual row 2.

Table 7 Next, Table 8 shows the results of developing, transferring, and fixing using the sample shop 17 to 20 single-component toners by the simultaneous method.
Shown below.

Table 8 It is clear from Table 8 [': Silicon carbide containing basin is 10wt%
If it is less than 1, the amount of charge injection has no voltage dependence, and the amount of charge injection is determined by the content t of the conductive agent.

In addition, when the silicon carbide content is 30wtTo or more,
It exhibited conductivity regardless of the content of the conductive agent.

From the above, in order to obtain a good fixed image by the simultaneous method, the silicon carbide content should be 10 to 30 wt, and the conductive agent content should be 1 to 5.
wt% is preferred.

〔Effect of the invention〕

According to the present invention, in toner used in electrophotography, silicon carbide and conductive fine particles are dispersed inside particles based on insulating resin, so that the resistance of the toner is reduced. The conductive toner changes depending on the bias voltage, and becomes a conductive toner that can be developed by the simultaneous method 5 at a certain voltage or higher. Furthermore, unless the full bias voltage is applied, the toner becomes insulating and can be transferred to plain paper by corona transfer or the like. As a result, if this toner is used in the simultaneous method, it is possible to perform good transfer without being affected by humidity, greatly simplifying the printing process! ! can be realized.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the implementation of the toner according to the present invention, FIG. 2 is a diagram showing how the toner according to the present invention is used by the simultaneous method, and FIG. 3 is a diagram showing how the toner according to the present invention is used. Figure 1 showing how the image is transferred by the corona transfer method - Ingredients Magnetic toner 2 Silicon carbide powder 3 Conductive agent 5 S-resistant resin and above Applicant Seiko Epson Co., Ltd. Agent Patent Attorney Saito Figure 2

Claims (2)

[Claims] (1) A one-component toner used in electrophotography, characterized in that silicon carbide and conductive fine particles are dispersed inside particles made of an insulating resin as a base material. (2) The one-component toner according to claim 1, wherein the toner is a magnetic toner.