JPH03168664A - Developing device - Google Patents

Abstract

PURPOSE:To stabilize toner electrifying quantity for a long period and to improve picture quality by using a toner control member constituted by forming resin coating layers incorporating a specific material on conductive base bodies. CONSTITUTION:As for the toner control member, the conductive substrates 31 and 41 are coated with the resin layer 32 and 42 incorporating surfactant. By thus providing the surfactant incorporated resin layers on the conductive substrates, charge mobility between the conductive substrate and the resin is improved. Therefore, charges whose polarities are opposite from the electrifying charges of resin are smoothly injected to the conductive substrates and the resin layers from an earth, and the triboelectric chargeability of the resin can be initialized. Even when the device is continuously driven for a long period, toner is not fixed to the toner control member, the toner electrifying quantity is stable for a long period, and thus, a stable picture can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrostatic latent image developing device using a monochromatic toner.

[Prior Art] Conventionally, as a method for developing an electrostatic latent image using non-magnetic toner, the toner on a toner carrier (i.e., a developing roller) is controlled by a blade-shaped or roll-shaped member (toner regulating member). A method is known in which the electrostatic latent image is formed into a thin layer and brought into contact with a photoreceptor on which an electrostatic latent image has been formed to develop it. In this method, when the toner is formed into a thin layer by the toner regulating member, it is charged by friction between the toner regulating member and the developing roller. This blade-shaped or roll-shaped toner regulating member is sometimes made of metal, but metal cannot provide a sufficient amount of charge to the toner due to frictional charging.

Therefore, there is a charge injection method in which a bias is applied to this metal member to impart charge to the toner. This makes it possible to control the charge applied to the toner. However, since the metal toner thinning member has poor releasability from the toner, the toner adheres to the surface of the member.
It becomes impossible to provide long-term stable charging and uniform thinning of the layer.

In response to this problem, as seen in Tokugan Sho issue,
It has been proposed to use polymers, fluororesins, etc. with excellent mold releasability as the toner regulating member. This prevents the toner from sticking and at the same time provides a sufficient amount of charge.

However, since these polymers are insulating resins, charges of opposite polarity generated in the toner regulating member when charged with toner tend to remain, and the remaining charges have the following effects.

(2) The time it takes for the toner to reach the saturation band mffi (the rise in charging of the toner) is delayed.

■ After long-term continuous operation, the saturation charge amount of the toner gradually decreases.

Therefore, it is not possible to obtain images of good quality that are stable over a long period of time.

In order to solve this problem, attempts were made to mix low-resistance particles such as carbon into the polymerer to lower the volume resistance and make it easier to leak residual charge, but this resulted in poor mold releasability and
Problems such as toner fusion occur, and other countermeasures have been required.

[Problems to be Solved by the Invention] In view of these circumstances, the present invention has been developed to provide a method that has excellent toner charging properties, does not cause toner fusion, and can maintain these characteristics stably for a long period of time. It is an object of the present invention to provide a developing device equipped with a toner regulating member that can be used.

[A Thousand Steps to Solve the Problems] As a result of intensive studies to solve the above-mentioned problems, the present inventors developed a toner regulating member by forming a horizontal conductive substrate with a resin coating layer containing a surfactant. They discovered that it is effective to make the structure of the invention, and came up with the invention.

That is, the present invention provides at least an electrostatic latent image holder that holds an electrostatic latent image, a toner carrier that makes the latent image visible on the holder, and a thin layer of toner that is formed on the toner carrier. In a developing device including a regulating member, the regulating member includes a resin layer containing an ionic surfactant on a conductive substrate.

The developing device of the present invention will be explained with reference to FIG.

In FIG. 1, l is a container, 2 is a toner, 3 is an agitator 4 is a supply roller, 5 is a developing roller as a toner carrier, 6 is a toner thin layer blade as a toner regulating member,
7 is a photoreceptor as an electrostatic latent image holder.

In FIG. 1, a toner container 1 contains a non-magnetic monocomponent toner 2. As shown in FIG. This toner 2 is conveyed by an agitator 3 to a toner storage section formed by a supply roller 4 and a developing roller 5, and is carried on the surface of the developing roller 5. Furthermore, a uniform thin layer is formed by the toner thin layer blade 6, and the toner is triboelectrically charged to a predetermined polarity.

The thin layer of toner is transported to the development area where the photoreceptor 7 holding the electrostatic latent image and the developing roller 5 come into contact, where the toner is electrostatically transferred from the developing roller to the photoreceptor 7 and the latent image is developed. be converted into

Further, FIG. 2 shows a case where a roll-shaped member is used as the toner regulating member, and this toner thin layer roller rotates in the opposite direction to the developing roller in the area where it contacts the developing roller.

In the above process, the toner is made into a uniform thin layer by means such as a thin layer blade or a thin layer roller, and is charged to a predetermined polarity. Contact pressure is applied.

Therefore, as described above, when used for a long period of time, toner is fused to these thin layer members, resulting in disturbance of the thin layer and a decrease in the amount of charge.

In the present invention, a material that does not cause such toner fusion and has excellent toner charging properties is used for the toner regulating member, and furthermore, in order to obtain long-term stability in toner charging properties, the above-mentioned specific structure is provided.

Examples of the toner regulating member are shown in FIG. 3a and FIG. 4a. Third
Figure a shows a blade shape, Figure 4 a shows a roll shape,
Surfactants 32, 4 on conductive substrates 3 {, 41 such as metals
The structure is coated with resin layers 32 and 42 containing 2.

In addition, as a modification of FIGS. 3a and 4a, surfactant 33
3b and 4b, in which resin layers 32- and 42- containing resin layers 32- and 43- are further provided with resin layers 34- and 44=.

As described above, electrical charges are accumulated in the resin.

However, by providing a resin layer mixed with a surfactant on the conductive substrate, the charge mobility between the conductive substrate and the resin is improved, so that the charge with the opposite polarity to the charge on the resin is transferred to the ground. This is because it is more smoothly injected into the conductive substrate and resin layer, and the triboelectric charging ability of the resin can be initialized.

The conductive substrates 31, 31-, 41, 41- are formed of metal, conductive resin, rubber, or the like.

Conventionally known metals such as stainless steel, iron, copper, and aluminum are used as the metal.

Conductive resin or rubber is imparted with conductivity by mixing conductive particles such as carbon black or metal particles.

Examples of the resin and rubber used in the present invention include alkyd resin, chlorinated polyether, chlorinated polyethylene, epoxy resin, fluororesin, phenol resin,
Resins such as polyamide, polycarbonate, polyethylene, methacrylic resin, polypropylene, polystyrene resin, polyurethane, polyvinyl chloride, polyvinylidene chloride, silicone, and butadiene rubber (
BR) Rubbers such as styrene-butadiene rubber (SBR), ethylene-propylene rubber (CR), chlorinated polyethylene, shrimp chlorohydrin rubber (CUR), nitrile rubber (NBR), acrylic rubber, urethane rubber, silicone rubber, fluororubber, etc. From the viewpoint of heat resistance and moisture resistance, silicone resins, fluororesins, silicone rubbers, and fluororubbers are preferred.

The same resin or rubber as above can be used for the resin layer coated on this conductive substrate. In the present invention, this is achieved by incorporating a surfactant into this layer, and any of nonionic, cationic, anionic, and amphoteric surfactants can be used.

Specifically, nonionic compounds include ester compounds such as fatty acids, ether ester compounds, ether compounds, and amide condensates. Examples of cationic salts include aliphatic amine salts and their quaternary ammonium salts, aromatic quaternary ammonium salts, and heterocyclic quaternary ammonium salts.

Anionic salts include alkyl carboxylates, N-acylamino acid salts, alkyl ether carboxylates, acylated peptides, alkyl sulfonates, alkylbenzene and alkylnaphthalene sulfonates, sulfosuccinates, α-olefin sulfonates, N - Acyl sulfonates, alkyl sulfates, alkyl ether sulfates, alkyl allyl ether sulfates, alkylamido sulfates, alkyl phosphates, alkyl ether phosphates, alkyl allyl ether phosphates, and the like.

Examples of amphoteric compounds include carboxybetaine, sulfobetaine, aminocarboxylic acid salts, and the like.

In particular, it is preferable to use fluorine-based materials from the viewpoint of environmental resistance.Specifically, nonionic materials include oligomers containing lipophilic groups of perfluoroalkyl groups, oligomers containing hydrophilic groups of perfluoroalkyl groups, and oligomers containing perfluoroalkyl groups and hydrophilic groups. Examples include alkyl ethylene oxide adducts, cationic examples include quaternary ammonium salts containing perfluoroalkyl, and anionic examples include monovalent metal salts of sulfonic acids and carboxylic acids containing perfluoroalkyl, and phosphoric acid. Examples include esters, and amphoteric examples include betaine containing perfluoroalkyl.

In addition, the upper resin layer 34- in FIG. 3b1 and FIG. 4b,
As 44-, the same materials as 32 and 42 described above can be used, but a filler such as a charge control agent can also be mixed in order to improve the electrification property with the toner.

These resins and surfactants are selected to have good compatibility with each other, but in terms of environmental resistance and mold release properties, fluororesin or silicone resin is preferred as the resin, and fluorine-based resins are preferred as the surfactant. surfactants are preferred.

Most preferred is a combination of a fluorine-based or silicone resin and a fluorine-based surfactant.

It is also possible to use a mixture of an ionic surfactant and a nonionic surfactant. In preparing this resin layer, an appropriate method such as spray coating, dipping, steam vulcanization, extrusion vulcanization, etc. may be employed.

The amount of the surfactant mixed is preferably 0.1 to 50 parts by weight per 1 part of solid content of the binder resin or rubber. More preferably, it is 0.5 to 20 parts by weight. If the amount is less than 0.1 parts by weight, the effect will not be sufficient, and if it is more than 50 parts by weight, the abrasion resistance and environmental resistance will be poor.

Further, as the toner, conventionally known toners can be used as they are. Specific examples of such toner include fine particles containing a coloring agent in a binder resin such as styrene-n-butyl methacrylate or epoxy resin, and if necessary, a charge control agent (nigrosine dye, basic dyes, etc.)
Examples include those to which a fluidizing agent such as silica, an abrasive material such as silicon carbide, and a lubricant such as a fatty acid metal salt are added.

[Examples] Hereinafter, the present invention will be explained in detail with reference to Examples and Comparative Examples.

Example 1 The following resin layered coating was applied to a copper plate by dipping and cured at 100°C for 71 hours to a film thickness of 20 μm.
m resin layers were formed.

[Resin layer forming components] Fluorine-based copolymer resin (Lumiflon 801C, manufactured by Asahi Glass) (solid content 50%) 100 parts by weight Coronate EH (50% xylene solution) 20 parts by weight fluorine-based ionic surfactant (cationic) (EPl32; manufactured by Mitsubishi Metals) 5 parts by weight M E K 400 parts by weight Example 2 The same procedure was carried out except that (EF102; Mitsubishi Metals) (anionic) was used instead of the ionic surfactant (EPl32) used in Example 1. Same as Example 1.

Example 3 The ionic surfactant (EFl32) used in Example 1 was replaced with a betaine type amphoteric surfactant [Ftardient 4].
008. The procedure was the same except that Neos ■] was used.

Example 4 The following resin layer forming components were coated on a copper plate by dipping and cured at 100°C for 71 hours to obtain a film thickness of 20μ1.
A resin layer (2) was formed.

Furthermore, the following resin was similarly spray applied on top of this, and 1
It was cured at 00° C. for 71 hours to form a resin layer (2) with a thickness of 20 μm.

[Resin layer ■ Forming component] Fluorine copolymer resin (solid content 50%) (Lumiflon 6
01C [Asahi Glass■] ) 100 parts by weight Coronae}EH
(50% xylene solution) 20 parts by weight ionic surfactant (cationic) (EF 132 Mitsubishi Metals) Sff
i part M E K 400 parts by weight [Resin layer ■ formation amount] Fluorine copolymer resin (solid content 50%) (Lumiflon 8
01C [Asahi Glass ■] ) 10 Offin part Coronate EH (50% xylene solution) 20 parts by weight M E K 400 parts by weight Example 5 In Example 4, an ionic surfactant (instead of EF132, EF102 Mitsubishi Metals (anionic) The procedure was the same as in Example 4 except that .

Example 6 In Example 4, a betaine type amphoteric surfactant [Ftergent 4] was used instead of the ionic surfactant (EFl32).
008. The procedure was the same except that Neos W] was used.

Comparative Example 1 The same procedure as Example 1 was carried out except that the ionic surfactant in Example 1 was not used.

Comparative example 2 Assume that the resin layer in Example 1 is not applied.

The toner thin layer blades of Examples and Comparative Examples obtained as described above were used in the developing device shown in FIG. 1, and the following evaluations were made.

[Toner charge amount] The following negative, iB. Using a blow-off method, the amount of charge in the developing device shown in Figure 1 was determined using
Charge amount at initial image■ Charge amount after running 10,000 sheets was measured.

(Toner used) Particle size 12 μ Styrene acrylic resin 100 parts by weight Carbon IO parts by weight Chromium-containing monoazo dye 2 parts by weight [Toner blade sticking] In the developing device shown in Figure 1, take out the blade after running 10,000 sheets. Ranked according to the following.

Rank A: Toner on the blade surface can be wiped off with a cloth or the like.

Rank B: A slight amount of toner remains after wiping.

Rank C: The toner cannot be completely wiped off and a thin film of toner remains.

Rank D: Melted toner is strongly adhered to the blade surface.

[Charge rise property of toner] Using the same negative toner as above, in the developing device shown in Fig. 1, the toner charge amount Q+ after driving the developing roller one rotation from the initial state and the charge amount Q5 after 5 rotations were measured. did.

The following developing rollers, replenishment rollers, and photoreceptors were used.

(Developing roller) Conductive silicone rubber coated with resin.

(Toner replenishment roller) Conductive urethane sponge (photoreceptor) O P C Table 1 [Effects of the invention] As explained above, according to the developing device according to the structure of the present invention, toner regulation can be achieved even during long-term continuous operation. The toner does not stick to the member, and the toner charge amount remains appropriately stable for a long period of time, making it possible to obtain stable images.

[Brief explanation of the drawing]

1 and 2 are schematic diagrams showing the developing device of the present invention, and FIG. 3 a1 FIG. 3 b1 FIG. 4 a and FIG. Diagram to explain.

Claims (2)

[Claims] (1) An electrostatic latent image holder that holds at least an electrostatic latent image, a toner carrier that makes the latent image visible on the holder, and a regulating member that forms a thin layer of toner on the toner carrier. A developing device comprising: a resin layer containing a surfactant on a conductive substrate; (2) The developing device according to claim (1), wherein the surfactant is a fluorine-based surfactant.