JPS62280763A - One component developing system - Google Patents

Abstract

PURPOSE:To obtain an image having good quality by allowing a specifically composed toner to exist in the form of a thin layer on a toner conveying member and developing a latent image by such toner. CONSTITUTION:The device of this system is provided with the toner conveying member 2, a toner layer thickness controlling member 3 and toner replenishing auxiliary members 4, 5. The toner 6 formed to the thin layer by using the developing device in which the toner replenishing auxiliary members 4, 5 are in contact with the toner conveying member 2 and the toner layer thickness controlling member 3 is in contact with the toner conveying member 2 is supplied to a latent image carrier 1 to develop the latent image. The toner essentially consisting of a coloring agent binder resin and at least one kind selected from the group consisting of an alkylsulfate, polyoxyethylene alkylphenyl ether, polyoxyethylene amine or amide, polyoxyethylene phytosterol, polyoxyethylene alkyl ether and polyoxyethylene oxypropylene alkyl ether is used in this case. The image of the quality equal to the quality of the initial image is thus obtd. even after continuous copying.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Technical Field] The present invention relates to a one-component developing system in electrophotography, and more specifically, a specific one-component developing system is developed on a toner conveying member adjacent to a latent image carrier. This is a new developing method in which a thin layer of developer is formed and the thin layer of toner is supplied to a latent image carrier for development.

[Prior art]

The dry developing method used in electrophotography, electrostatic recording, etc.
There are methods that use a two-component developer consisting of toner and carrier, and methods that use a one-component developer that does not contain carrier. The former method allows relatively stable and good images to be obtained, but it is not possible to obtain images of constant quality over a long period of time because carrier deterioration and fluctuations in the mixture ratio of toner and carrier tend to occur. <<.

Additionally, there are difficulties in maintaining the device and making it more compact.

Therefore, the latter method using a one-component developer, which does not have these drawbacks, is attracting attention.

By the way, in this method, 1 usually at least one toner conveying member conveys the toner (developer), and means for visualizing the electrostatic latent image formed on the latent image carrier by the conveyed toner. However, in this case, it is said that the layer thickness of the toner conveyed on the surface of the toner conveying member must be made as thin as possible. This also applies when using a two-component developer with a very small carrier diameter, and especially when using a -component developer and using a toner with high electrical resistance. When this happens, the toner needs to be charged by a developing device, so the layer thickness of the toner must be made extremely thin. This is because if the toner layer is thick, only the area near the surface of the toner layer will be charged, making it difficult to charge the entire toner layer uniformly.

In response to these demands, various methods have been proposed for regulating the toner layer thickness on the toner transport member (toner layer thickness regulating means).A typical example is a doctor blade that is used to transport the toner. The toner layer is placed opposite the toner conveying member, and the toner conveyed on the surface of the toner conveying member is pressed down by a suppressing member (doctor blade) to control the toner layer thickness.

However, in the past, when attempting to obtain an image using a developing device having the above-mentioned toner layer thickness regulating means, a good toner thin layer could be formed on the toner conveying member in the initial stage, but the Immediately after the toner is transferred onto the latent image carrier, the next toner supplied onto the conveying member tends not to form a thin layer to the same extent as before development. In other words, taking the example of a cylindrical toner conveying member, there is a phenomenon in which the amount of toner adhesion is significantly different between the image corresponding to the first rotation of M and the i image corresponding to the subsequent rotation. Insufficient thin layer formation in the second rotation also means that the amount of charge on the toner is insufficient.

Another problem arises in that weakly charged toner scatters from the conveying member and contaminates the surrounding area.

Furthermore, as you use it for a long time, you will start to see images with background stains and white streaks. This is because the toner generates heat and melts due to repeated friction between the toner layer thickness regulating member and the toner layer thickness regulating member during long-term development operations, and this melts and adheres to the surface of the toner layer regulating member and toner transporting member, reducing the toner charge amount. it is conceivable that.

〔the purpose〕

The present invention solves the above-mentioned defects by making a toner of a specific composition exist in a thin layer on a toner conveying member, and by forming 11 latent images with the toner, a high-quality image can be obtained. The present invention provides a one-component development method for electrophotography.

〔composition〕

The one-component development system of the present invention includes a toner conveying member, a toner layer thickness regulating member, and a toner replenishment auxiliary member, and the toner replenishing auxiliary member, the toner conveying member, the toner layer thickness regulating member, and the toner conveying member correspond to each other. When developing a latent image by supplying thinned toner to a latent image carrier using a developing device that is in contact with it, colorant, binder resin, alkyl sulfate, polyoxyethylene alkyl butenyl ether, and It is characterized by using a toner whose main component is at least one selected from the group consisting of oxyethylene amine or amide, polyoxyethylene butystyrene, polyoxyethylene alkyl ether, and polyoxyethylene polyoxypropylene alkyl ether.

Incidentally, as a result of various studies to achieve the above object, the inventors of the present invention have found that good copies can be obtained by incorporating the alkyl sulfate or the like into a conventional toner, and preferably by using a special toner conveying member. The present invention was completed based on such knowledge.

To explain the present invention in more detail, the one-component developer (toner) used in the method of the present invention contains at least a colorant, a binder resin, and the alkyl sulfate as main components, as described above. It's ours. Here, the amount of the alkyl sulfate in the toner is 1 to 10% by weight, preferably 0.5 to 5% by weight, and if it is less than 0.1% by weight, the effect of preventing toner adhesion is poor. I can't perform well, and on the contrary, I'm 10 times heavier.
If the amount exceeds %, the crosstalk during toner production will be insufficient, making it impossible to obtain a homogeneous toner. Hexaalkyl sulfates and the like have the following structural formula.

(1) Alkyl sulfate R1-○-so; ) (2) polyoxyethylene alkylphenyl ether, (3) polyoxyethylene amine or amide 1-20
is an integer. ) (4) Polyoxyethylene phytosterol (However, 1
~30 integer. ) (5) Polyoxyethylene alkyl ether R" -〇(-CI-1, Cl-1, ○)nH (However, R1 is an alkyl group having 6 or more carbon atoms, . is an integer from 1 to 2o.) (6) Polyoxyethylene polyoxypropylene alkyl ether CH.

R1-0(-CH,CI-(0翰FCH,CH,O).

H (however, R1 is alkyl having 6 or more carbon atoms) L4. □ is 1
An integer between ~10.

. is an integer from 1 to 30. ) As the colorant and binder resin, any of those used in electrophotographic toners can be used. For example, a typical coloring agent is copper phthalocyanine.

Examples include anthraquinone dyes, quinacridone, rhodamine dyes, azo dyes, indigo dyes, etc.
Typical examples of binder resins include polystyrene, chlorinated paraffin, polychlorinated paraffin, polyvinyl chloride, phenol resin, epoxy resin, polyester, and polyamide.

Examples include polymers such as polyacrylic acid resin, polystyrene, and polypropylene, and copolymers containing these monomers.

Toner production involves adding the colorant, binder resin, alkyl sulfate, etc., which may be used alone or in combination of two or more, in a predetermined ratio, melting and kneading with a roll mill, and then roughening with a hammer mill. The toner may be pulverized and further finely pulverized using a jet mill to obtain a one-component magnetic toner having a particle size of approximately 5 to 20 μm. Also, in the production of -component magnetic toner: i'
An appropriate amount (10 to 60% by weight) of magnetic material may be added to the above-mentioned mixed material.

FIG. 1 of the accompanying drawings shows a non-magnetic material useful for carrying out the method of the present invention.
FIG. 1 is a schematic cross-sectional view of an example of a developing device using component-based toner. As shown in FIG. 1, the toner 61 built in the toner tank 7 is forcibly brought to the sponge roller (toner replenishment auxiliary member) 4 by the stirring blade (toner replenishment auxiliary member) 5, and the toner is It is offered to roller 4. Then, as the sponge roller 4 rotates in the direction of the arrow, the toner taken into the sponge roller 4 is carried to the toner conveying member 2, where it is rubbed, electrostatically or physically attracted, and the toner conveying member 2 It rotates strongly in the direction of the arrow, and a uniform thin layer of toner is formed by the steel elastic blade (toner layer thickness regulating member) 3 and frictionally charged. Thereafter, the toner is transported to the surface of the electrostatic latent image carrier 1 that is in contact with or in close proximity to the toner transport member 2, and the latent image is developed.

Note that developing devices suitable for the toner of the present invention are not limited to those described above.

The one-component development system of the present invention, however, is particularly effective when images are formed using such a developing device using the specific toner described above.

Next, examples and comparative examples will be shown. All parts herein are parts by weight.

Example 1 Styrene-n-butyl methacrylate copolymer 50
Part low molecular weight polyethylene 5
Triiron tetraoxide (EPT-LGOG)
A mixture consisting of 40 parts Nigrosine Base Ex (Orient Kagaku M), 2.5 parts sodium lauryl sulfate, and 2.5 parts Tucor 5LS) was melted and kneaded by heating at 120 to 130°C for about 30 minutes using a hot roll mill, and then heated to room temperature. After the mixture was cooled to a temperature of 100.degree. C., it was coarsely pulverized using a pulverizer, further finely pulverized, and classified using a zigzag classifier to produce a toner having a particle size of 5 to 15 .mu.m.

When continuous copying was performed using this toner using the developing device shown in Figure 1, the images were good, especially when compared to the initial image.
No difference in image quality was observed after continuous copying of 0 sheets, and no white streaks or the like were observed.

In addition, there is no change in the amount of charge on the toner, and the toner transport member
No fusion of the toner to the toner layer thickness regulating member was observed, a uniform thin toner layer was formed on the toner transport member, and no toner filming on the organic photoreceptor was observed.

Incidentally, the electrostatic iJ1 image was formed by charging the photoreceptor to 1,800 μm and then exposing it to light to form a latent image.

In addition, instead of the sodium lauryl sulfate, polyoxyethylene octylphenyl ether was used as O
P-30), polyoxyethylene stearylamine and Tukor AMNS-15).

Tucor B for polyoxyethylene phytosterol
Similar results were obtained when polyoxyethylene lauryl ether was used as Tucor's BPS-25) or polyoxyethylene polyoxypropylene decyltetradecyl ether was used as Tucor's PEN-4612).

For comparison, a toner was prepared in the same manner except that it did not contain sodium lauryl sulfate, and the same copying test was conducted. the result.

Initially, a good toner thin layer was formed and no abnormality was observed in the image, but after 1000 copies were made continuously, toner fusion occurred on the toner layer thickness regulating member, and the image became smudged. When continuous copying was continued, white streaks appeared on the image, and toner filming was observed on the photoreceptor.

Example 2 5 to 14 were prepared in the same manner as in Example 1 using a mixture having the following composition.
A toner with a particle size of μm was produced.

Styrene-acrylic acid copolymer (Himer SBM-73 manufactured by Sanyo Chemical Co., Ltd.)
85 parts low molecular weight polypropylene
5 parts nigrosine dye (Bontron N-06 manufactured by Orient Chemical Co., Ltd.)
2 parts Copper phthalocyanine blue (Lionol Brae KL manufactured by Toyo Ink Co., Ltd.) 5 parts Sodium lauryl sulfate and Tucor Co. 12SL, S) 3
Next, when a copying test similar to that of Example 1 was conducted using this toner, good results similar to those of Example 1 were obtained.

In addition, instead of the sodium lauryl sulfate, polyoxyethylene nonylphenyl ether was used with Tucor's NP-
15), polyoxyethylene stearylamine (TAM
US-15), polyoxyethylene phytosterol (
Similar to Example 1, good results were obtained when polyoxyethylene cetyl ether (BC-20TX) or polyoxyethylene polyoxypropylene decyltetradecyl ether (PEN-4612) was used. It was done.

Example 3 5 to 14 were prepared in the same manner as in Example 1 using a mixture having the following composition.
A toner with a particle size of μm was produced.

Polystyrene (Picolastic D-125 manufactured by Esso Standard Oil Co., Ltd.) 50 parts molecular weight polypropylene 5
Triiron tetroxide (EP T-1000)
40 parts Nigrosine dye (Bontron N-0
6) 3 parts Sodium cetyl sulfate, 2 parts Tukol H8C3) Next, using this toner, a copying test similar to that in Example 1 was conducted, and as in Example 1, good dehulling was obtained.

In addition, instead of the sodium cetyl sulfate, polyoxyethylene octylphenyl ether (OP-30), polyoxyethylene stearylamide and T
AMDS-4), polyoxyethylene phytosterol (BPS-30), polyoxyethylene oleyl ether and Tucor BO-50) or polyoxyethylene polyoxypropylene cetyl ether (RPC).
Example 4 using -34) 5 to 14 in the same manner as in Example 1 using a mixture with the following composition.
A toner with a particle size of μm was produced.

Styrene-acrylic acid copolymer (HIMER SBM-73
) 78 part molecular weight polypropylene
5 parts nigrosine dye and grosine base EX)
2 parts carbon black (C4 manufactured by Mitsubishi Chemical Industries, Ltd.)
44) 12 parts Sodium cetyl sulfate and 3 parts 5C8) manufactured by Tukor Co. Next, using this toner, a copying test similar to that in Example 1 was conducted, and the same good results as in Example 1 were obtained.

Moreover, instead of the sodium cetyl sulfate, polyoxyethylene octylphenyl ether (OP-30), polyoxyethylene stearylamide (TAMDS-
4) Polyoxyethylene phytosterol (BPS
-30), polyoxyethylene oleyl ether (
Similar to Example 1, good results were obtained when polyoxyethylene polyoxypropylene cetyl ether (BO-50) or polyoxyethylene polyoxypropylene cetyl ether (PBC-34) was used.

For comparison, a toner was prepared in the same manner except that sodium cetyl sulfate was not included, and the same copying test was conducted, which yielded similar undesirable results as in the comparative test described in Example 1. .

〔effect〕

As is clear from the above embodiments, according to the method of the present invention, images of the same quality as the initial image can be obtained even after continuous copying. Furthermore, the method of the present invention has little environmental variation and can form a good uniform toner thin layer even under high temperature and high humidity conditions.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of equipment suitable for implementing the method of the present invention. 1... Electrostatic latent image carrier 2... Toner transport member 3
...Elastic blade 4...Sponge roller 5.
...Agitating blade 6...Toner 7...Toner tank

Claims (1)

[Claims] 1. A developing device comprising a toner conveying member, a toner layer thickness regulating member, and a toner replenishment auxiliary member, and in which the toner replenishing auxiliary member and the toner transporting member, and the toner layer thickness regulating member and the toner transporting member are in contact with each other. When a toner made into a thin layer is supplied to a latent image carrier to develop a latent image, a colorant, a binder resin, an alkyl sulfate, a polyoxyethylene alkylphenyl ether, a polyoxyethylene amine or an amide, a polyamide, etc. A one-component development method for electrophotography, characterized in that a toner containing as a main component at least one member selected from the group consisting of oxyethylene phytosterol, polyoxyethylene alkyl ether, and polyoxyethylene polyoxypropylene alkyl ether is used.