JPS63250659A - One component toner - Google Patents

Abstract

PURPOSE:To produce a one component toner capable of carrying out development by a simultaneous process by forming toner nuclei using a thermoplastic resin as binder resin, copper sulfide as a P-type semiconductor, and a magnetic material, etc. and coating the surface of the toner nuclei with an insulating material. CONSTITUTION:CuS as a P-type semiconductor 2, another pigment 4, and a magnetic material 3 (e.g. Fe3O4, etc.) are dispersed in a thermoplastic resin such as polyacrylonitrile, etc. as binder resin 1, to form toner nuclei 5. An insulating material 6 such as hydrophobic colloidal silica, etc. is coated on the surface of the toner nuclei with 10-90% percentage of covering to obtain thus a one component toner. Since a P-type semiconductor is used therein and the toner nuclei are coated with an insulating material, the charge injection in a developing stage is carried out at a semiconductor part, and transfer is carried out using the electric charge of the previously charged insulated part because of absence of injection of reverse electric charge to the semiconductor part. Thus, a satisfactory transferred picture image is obtained without being influenced by the humidity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to the composition and composition of one-component trees used in electrophotography. It flashes in my mind.

[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 using the Carlson process, two-component magnetic brush development method and float electrode effect development method (1" E ICD)
In the method), an insulating non-magnetic tree is used, and in the jumping development method, an insulating magnetic toner is used, and in the case of the Elect-t1 fax, a conductive magnetic toner is used.

Recently, a method using new xerography technology (hereinafter referred to as the "simultaneous method") that forms an image by simultaneously performing exposure and development, which has the potential to greatly simplify the τ3 process, has been introduced in various places. For example, JP-A-58-1530
57 has been proposed. According to this simultaneous method, a charger,
Static eliminator and Creeley processes are no longer required, and no discharge occurs, simplifying the process and eliminating the need for discharge.
- can be saved, and the device can be made smaller and lower in cost. To give an overview of this 0 o'clock method, the best developing method is to use a conductive magnetic tri-pole brush to which a bias voltage is applied during exposure to pass the surface of the image forming body containing the photoconductor layer. When the photoconductor acts as an insulator (unexposed area) and when it acts as a conductor (
There is a difference in the charge It injected into the tray in contact with the image forming surface due to the bias voltage due to the exposure part), and the difference in charge L is the electrostatic force applied to the surface of the image forming body. This difference makes it possible to form toner images.

[Problem that the invention seeks to solve]

However, due to the toner used in the simultaneous method, its electric charge is neutralized in a short relaxation time and the electrostatic impact force on the paper is weakened. transfer rate decreases. Particularly in high humidity conditions, the conductivity of paper increases, and charge injection of opposite polarity +/I occurs from the paper to the toner, resulting in the disadvantage that the well-known electrostatic transfer method cannot transfer onto the paper at all. was.

1-1 of the present invention is to provide a tod which can be developed by a simultaneous method and can be transferred to Y paper by a one-step transfer method.

[Means to solve problems 7 times a month] The one-component toner in the present invention uses a thermoplastic resin as a binder resin and 1) type copper sulfide (CuS) as a semiconductor material once a month.
In addition, by adding tube coloring material and magnetic material, the surface of the -9 body toner has an insulating substance coverage rate of 10~! ]0% to 7!
-Characterized by tinobing.

[Effect]

According to the 4iη structure of the present invention, during image formation in the simultaneous method, the charge injection into the toner in contact with the surface of the iil+i image forming member is 1) in the positive direction of the mold soil-Ω body and in the opposite direction of Toyaria. Residual negative due to the transfer to the +'i? The 'I' u force is reversed by contact with the paper. Electrostatic transfer can be performed by applying the electric charge (L1) on the insulating portion of the surface of the toner particle.

〔Example〕

FIG. 1 shows a cross-sectional view of a toner in an embodiment of the present invention. The toner of the present invention has an 11-layer structure in which a semiconductor material 2, a magnetic material 3, a pigment 4, and other additives are dispersed in a binder resin 1, and an insulating material 6 is dotted on the surface of the toner having a value of 5. ing. The binder resin is preferably a commonly used known thermoplastic resin, such as polystyrene and its copolymers, polyester and its copolymers,
Polyethylene and its copolymers, acrylic resins, vinyl resins (such as chinese fat, etc.) are used alone or in combination.As magnetic materials, known magnetic powders, triiron tetroxide,
γ-ferric oxide, chromium dioxide, nickel ferrite,
Use iron alloy powder, etc. As the face r1, carbon black, spirit black, Nige fJ Shin, etc. are used. Furthermore, it is preferable to add a fluidity improver as another additive.

Further, as the insulating material used in this toner, hydrophobic particles or silica particles are used.

As a method for producing toner cough 5 using Nisashihara f: [, kneading, crushing, and spraying methods can be used. Furthermore, an insulating material is added to the toner core 5 at a constant IV1.
The coating method is carried out by coating by a hot air flow treatment method or a ball mill treatment method, and then removing a predetermined amount of the insulating material by high-speed air flow or ultra-7T wave vibration.

[Example 1] Polyacrylontrile PΔN, ゛1 as a thermoplastic resin
1 Copper sulfide (CuS) was used as the conductor material, triiron tetroxide was used as the magnetic material, and Nige L1 thin was used as the coloring agent, and the raw material R was weighed out for the composition not shown in Table 1. Thereafter, the mixture was kneaded with a screw extruder, pulverized with a jet mill, and classified with an air classifier to produce tri°-nuclei of 10 to 15 ttm.

Next, the bipedal bird nucleus was coated with hydrophobic colloidal silica as an insulating material using a ball mill, and
A toner was prepared by adjusting the coverage to a predetermined coverage rate shown in Table 2 using sonic vibration.The surface coverage rate was determined by SEM and TEM.
Obtained from Photo J'r.

Table 1 Table 2 Next, the sample Nos. 1 to 4 trinuclei were developed by a simultaneous method using one-component tri-nuclei having the coverage rates A to D in Table 2, respectively. , transfer, and fixing were carried out, and a good fixed image could be obtained.

[Comparative Example 1] Tree nuclei shown in Table 3 were produced using the same raw materials and manufacturing method as in [Example 1]! JJ construction, and the coverage shown in Table 4 was applied.

Table 3 Table 4 Next, Table 4 was added to each of the toner nuclei of Sample No. 5 to 8.
When developing, transferring, and fixing were performed using a single-component toner having a coverage rate of IC to H, a good fixed image could not be obtained. This Hi prisoner has a CuS content of 5
If the CuS content exceeds 0%, the ratio of the resin to the magnetic material becomes small (and development or regular processing becomes impossible).If the CuS content is less than 20%, the IN? resin will not exhibit semiconductivity and development will not be possible. Therefore, Cu
5) The content of 1°j11 is preferably 20 to 50%. Regarding the coverage rate of the insulating material, if it exceeds 90%, sufficient charge injection will not be performed and development will not be possible.
Further, if the amount is less than 10%, the amount of charge is insufficient and transfer 77 cannot be performed. Therefore, the coverage rate of the insulating material is 10
~90% is preferred.

[Example 2] Polystyrene was used as the thermoplastic resin, CuSs was used as the semiconductor material, triiron tetroxide was used as the magnetic material, and spirit black was used as the coloring agent. The composition was weighed, the raw materials were dissolved and dispersed in acetone, and a bird cough of 10 to 15 μm was produced by a spray method. Next, hydrophobic colloidal silica was used as an insulating material for the tri-nucleus, and the balance J:EL was used to obtain the same coverage as in Table 2 of [Example 1]. After mixing, coating was carried out by spraying into a hot air stream.Surface coverage was determined by SEM and TIζM.

Next, regarding these samples [Example! 〕alike,
When development, transfer, and regular printing were performed by the simultaneous method, a good regular image could be obtained.

[Comparative Example 2] A toner was produced using the same raw materials and manufacturing method as in [Example 2] and having the same composition as in Table 3 and the coverage rate in Table 4 in [Comparative Example 1].

Next, when these samples were subjected to development, transfer, and regular printing in the same manner as [Comparative Example 1], it was not possible to obtain a good fixed image. From this, it is preferable that the irradiation rate of CuS is 20 to 50%. Moreover, the coverage rate of the insulating material is preferably 10 to 90%.

(Effects of the Invention) As described above, according to the present invention, in the electronic dull Jl+Tree, thermoplastic resin, 'r,
74 P-type copper sulfide (CuS) is used as the body material, and the surface of the conductive toner is coated with an insulating material! 1, the charge if person is carried out by the half-nog body part. Since there is no injection of opposite charge into the semiconductor part, the transfer can be carried out only by the pre-charged dead body part. As a result, if this toner is used in the same U7 method, it will not be affected by 19 degrees and will be able to obtain a good transferred image. can.

4. R-baf of the drawing! li explanation ■Figure 1 shows an example of the toner according to the present invention. 2...Semiconductor material 6...Insulating material that's all Applicant: Seiko Epson Corporation Ward 1

Claims (1)

[Claims] In toner for electrophotography, a thermoplastic resin is used as a binder resin, P-type copper sulfide (CuS) is used as a semiconductor material, and an insulating material is added to the surface of a semiconductive toner made by adding a coloring material and a magnetic material. A one-component toner characterized by coating with a coverage of 10 to 90%.