JPS59181360A - Color toner composition for electrophotography - Google Patents

Abstract

PURPOSE:To obtain a color toner which permits control of electric charge or resistance value and has excellent cleaning characteristic and preventiveness of drum filming by incorporating either one or both of a colored pigment and colored dye together with a binder resin and conductive zinc oxide in the toner. CONSTITUTION:A color toner compsn. incorporated therein with either one or both of a colored pigment and a dye and a synthetic or natural resin as a binder as well as conductive zinc oxide particles having about 100OMEGAcm specific volume resistivity as a charge or resistance controlling agent is prepd. After the compsn. is melted and kneaded, the mixture is cooled, coarsely ground, pulverized and classfied, by which the color toner particles are obtd. Hydrophobic silica and ultrafine particles of alumina of a gas phase method are added to such toner and a developer mixed with carrier particles is obtd. The color developer for electrophotography having an excellent cleaning characteristic, preventiveness of dry filming, fixability, etc. is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field: The present invention relates to a color toner composition containing a color toner derivative for photographic use, particularly conductive zinc oxide particles.

Conventional technology: Conventionally, charging process 1 image exposure process, development process, transfer process,
In electrophotography, which consists of a cleaning process and a fixing process, in order to always produce a stable image, it is necessary to remove untransferred toner remaining on the surface of the photoreceptor after transfer to plain paper. It is also necessary to provide a toner composition with excellent cleaning properties or a developer containing the same.

Based on knowledge from parent and image materials, it is known that one way to improve this cleaning property is to adjust the drag value of the toner itself to an appropriate value. For example, in a two-component black developing section, since carbon black, which is generally used as a coloring component, has commercial properties by itself, toner repulsion control can be performed more easily. It always has the same cleaning properties as Itosumi.

On the other hand, in bipartite visual agents containing color toners, 2 and 1
(Of course, carbon black cannot be used as a 41 agent, so the toner itself tends to have no resistance.

Generally, a surfactant can be used to completely prevent color toner from aging. This surfactant oozes out into the toner surface as its own essence.

At present, this is undesirable because it causes so-called "pleasing", which significantly reduces the resistance of the toner surface due to the influence of zero humidity, and deteriorates the properties before development, especially the toner properties.

Purpose of the invention: The purpose of the present invention is to: #electronic■1. control()shi< is 71 exclusive value 1
It is an object of the present invention to provide a color toner for electrophotography, f+111, which has excellent cleaning properties and drum filming prevention properties, since it is capable of containing 1511 flies. The main object of the present invention is to eliminate edge effects and have a high transfer speed.

Therefore, it is an object of the present invention to provide a color toner composition for electrophotography that can produce clear images as desired.

Purpose of invention: The color composition of the present invention has a binder resin.

The above object is achieved by containing a conductive oxidation compound, lead particles, and at least one of a colored pigment 2 and a colored dye.

The color ready-made product of the present invention has a binding tree of 11 effects 1001
(to) 1 to 20 parts by weight of conductive zinc oxide particles per part.

The conductive oxidizing lead containing 1 to 15 small parts of a colored pigment and/or 0.1 to 15 i parts of a colored dye is a powder with a gray-white appearance, and its pure ZnO content is Maximum 990% one-body jet specific leverage value is approximately 100Ωcm (
Ill constant pressure crab 576 to 9/ca), the average particle diameter is maximum 1.55μ1, and the grain distribution is 4μ or less, the minimum is 60 coefficient and 10
μ or more is up to 15%, and p) Iffη is 7.0 to 7
．． Zinc oxide having a characteristic of B ■ J is fundamentally different from zinc oxide, which has a high resistance value of 1013 Ωm. Such conductive zinc oxide is obtained, for example, from Honjo Chemical Co., Ltd. and is described in detail in Patent Nos. 1029615 and 1029616. The volume-specific resistance of this zinc oxide is determined as follows: ■ Fill a glass cell with a sample and set it on a pedestal; ■ Apply a pressure of 20 ky/d to the oil field with a hand press; Sample A pressure of 576 kg/C#t is applied due to the area; ■ Read the resistance from the digital display resistance meter; and ■ Multiply the resistance value by the cross-sectional area of the sample to calculate the height of the sample read from the dial gauge. Divide by to find It 1>'r fUj of the sample. Measurements of sashimi samples are made at ¥300,000 yen temperature and in air.

The above-mentioned binder resin does not need to be special.

Any of the known natural, semi-synthetic or synthetic ffN+1 materials that exhibit adhesive properties under the application of heat or pressure may be used. These resin binders are 1 thermoplastic, 4 and 4.
It may be a non-cured thermosetting resin or a condensate of a thermosetting resin. Useful natural oils include balsam tree 11 yen
There are 1° rosin, shellac, and copal. These natural fats can be modified with vinyl resin, acrylic (drum fat, alkyd resin, phenol Rei I, epoxy resin, orange (oil-based resin), etc.) or two or more types. Good. 1 synthetic resin and 2 parts, reinforced vinyl resin, vinylidene chloride + ffl11, self-iei wave vinyl resin; vinyl acetal such as polyvinyl butyral, silica: or vinyl intermediate resin such as vinyl ether offshore. , polyacrylic esters, polymethacrylic esters, acrylic acid copolymers, methacrylic acid copolymers; polystyrene;

Styrenic resins such as hydrogenated styrene resins, polyvinyltoluene, and styrene co-conjugates; polyamides such as nylon-12, nylon-6, and polymerized fatty acid-modified polyamides; Polyesters such as lephcrate/isophthalate: phthalate alkyd resins. Phenol formaldehyde tree flavor,
Ketone 41J 11￥￥; Coumarone-indene use; Terpene, order ii-7; Amino-C such as urea-formaldehyde resin, melamine-formaldehyde resin, etc.
4. Resin: Epoxy resin and the like can also be used.

These IJW resins may be a combination of two or more silks such as phenol-epoxy cedar resin or amino-epoxy resin.

The above colored pigments need to be exceptional (without ri,
Known pigments are used. An example of this is yellow pigment. Zinc yellow. Cadmium yellow, yellow-ferric chloride. Examples include Mineral Fast Yellow. Red yellow lead is an orange pigment.

Molybdenum Orange, Permanent Orange Grk,
There are Biran Rommelengzi and Palkan Orange. Red pigments include red pigments, cadmium red, fastlet, red lead 1m (hydroxide < silver cadmium, etc.).Purple fHi ln include manganese purple, fast violet B, methyl violet lake, etc.
Blue'f! a di'l *! ) is Konyoi.

These include cobalt blue, alkaline blue lake, and phthalocyanine blue. As a green temporary pigment.

Chrome Clean, Chrome Oxide, Pigment Clean B
, malachite cleanlay-#, etc.

As for the white pigments, lead-captured white pigments, acidic acid L titanium 7° anti-seven white pigments, and Tsukuda 11-hybrid lead-captured pigments were used. Examples of monomer pigments include halide powder, barium carbonate, clay, silica, and white carbon.

The dyes of the present invention also need not be special.

Any known dye may be used. Let me give you an example of that.

As a yellow dye, Eisen Spin Yellow GL (11(
C, l, 5olvent Yellow 51),
Examples include Eisen Spin Yellow 3 R11. As an orange dye, Eisens Viron Orange G K H (C,
l, SolventOrange 37), Huise'
7 Suhion Orenshi 3 RH (C0l, 5olve
nt Orange 4(1), etc. Red dyed KA
As, Eisensviron Red GE 11 (c,
1゜5olgent 1Led 34), Eisen Subiron Red B Snake 1-1 (C-1゜5olvenc
1 (ed 83). As a color dye.

Eisensviron Violet RH (C-L +5ol
ventViolet 21). As a blue dye, Isenspiron Blue-GN (, Sumiplast Blue OA (C, l, 5olvent B)
lue 36) There is.

And as a green dye, Aizensvironkuri-73G
N HGonc 5special, Queer Resin Cree: / A (c, i, 5olvent Green
3) There is a thing.

The above-mentioned Yuzuki Shurin, Hiroichi, sexual oxidation! Lead and colored pigments/or colored dyes are mixed together in one constant mixture and melted and kneaded. After cooling, the powder is coarsely pulverized to make the particle size uniform and used as a color toner in I'gi distillation. Then, if necessary, it is subjected to an appropriate blush treatment. This composition is mixed with a carrier such as iron powder and ferrite at a predetermined mixing ratio to prepare a two-component color developer.

Margin below Example: The present invention will be explained below based on examples.

Example 1 Styrene-2-ethylhexyl methacrylate copolymer (manufactured by Gutdeyer Co., Ltd., ACL) 90 parts by weight, low molecular weight polypropylene (manufactured by Sanyo Chemical Co., Ltd., Viscoel 550p) 2
Parts by weight, red monoazo pigment (manufactured by Sanin Shiki Co., Ltd., Fast
-Red2BE) 6 parts by weight.

Red oil-soluble dye (manufactured by Hokoya Chemical Co., Ltd., Spiron Red GR
1 part by weight of LH Special) and 5 parts by weight of conductive zinc oxide particles (electrical resistance 100Ω, manufactured by Honjo Chemical Co., Ltd.) were thoroughly mixed in a Henschel mixer, and then in a pressure kneader.
Melt and knead. After cooling, this is coarsely ground. Next, it is pulverized using an ultrasonic jet mill pulverizer. This was classified and the average diameter was 11.9p with a particle size distribution of 5 to 20P%.
A color toner composition of m was obtained. This was further surface-treated with 0.1% hydrophobic silica (Aerosil R-972, manufactured by Nippon Aerosil Co., Ltd.) and 1% vapor-grown alumina ultrafine particles A120a'-GO.

A developer was prepared by mixing 10 parts by weight of the obtained toner composition and 100 parts by weight of iron powder. The amount of triboelectric charge (blow-off method) of this developer was measured and was -18.1 pC/9.
Met. In addition, this developer is used for dry copying a (DC=A
2. Use blade cleaning.

When the copy was placed in a copying machine (manufactured by Sanda Kogyo Co., Ltd.) and copied, a clear red copy with excellent resolution, high image density, and no background fog was obtained with no edge effect. 5an': No cleaning defects were observed even in the square solid image of <5 lines. Also, when 2,000 sheets were continuously copied, the initial image density (1, D) was 1.08° and the background fog density (F, D) was 0.001, but 2
Even the ,000th sheet is 1. D is 1.10. And F and D are 0
．． 002, which showed very stable image retention. Drum filming was also not allowed at all. Further, the transfer efficiency of the developed toner calculated from the amount of toner consumption and the toner i recovered by cleaning was 93%. moreover,
The bias current flowing from the developing sleeve to the photosensitive drum side via the developer is initially 12.1 PA, and 2.
Even on the 000th sheet, it was 10.5 μA. From this, it was found that the increase in resistance of the developer obtained in this example was considerably suppressed.

Example 2 Styrene-2-ethylhexyl methacrylate copolymer (ACL) 90 parts by weight 7 Low molecular weight polypropylene (55
A toner was prepared in the same manner as in Example 1 using a composition consisting of 7 parts by weight of a blue phthalocyanine pigment (Cyanine Blue #l, 000. manufactured by Dainichiseika Kaisha, Ltd.) and 4 parts by weight of conductive zinc oxide particles. It was adjusted. This was mixed with an iron powder carrier to obtain a developer. When a copy test was conducted in the same manner as in Example 1 using this developer, a good blue copy image was obtained. Emojiya 5 cin X 5
No cleaning defects were observed in cm solid images. Even in the 2,000-sheet continuous copy test, the initial 1. D
1.13. Therefore, F and D are 0.002, and 2,0
Even on the 00th sheet, 1. Dl, 09 and F, Do, 0
02, indicating stable image retention. There was no drum filming at all.

Transfer efficiency was 95%. The initial bias current value is 1.
It was 14 μA, and 10.1 pA for the 2,000th sheet. It can be seen that the development of high resistance of the developer is considerably suppressed.

1 person Ding Machi K Color Comparative Example 1 A red toner was obtained in the same manner as in Example 1 except that conductive zinc oxide was removed from the toner formulation of Example 1. Using this, a developer was prepared in the same manner as in Example 1. When the amount of triboelectric charge was measured, it was -18.5 μc/y.

When a copy test was carried out using this developer, a red copy with high image density and low background fogging density with no edge effect and excellent resolution was obtained at the initial stage.

However, cleaning failure occurred with a 5ci×5cm peta image. In the 2000-sheet continuous copy test, initial 1. D
1,09 and F,DO,001. However, 2
1,000th photo. D is 0.84. And F and D are 0.0
03, the image density decreased due to the edge phenomenon.

In addition, local skin fogging due to drum filming (
0,015) occurred. The transfer efficiency was 8696, which was 93% of Example 1 (lower than that in Example 1).
The initial bias current value is 5.4 μA and 2,000 μA.
The second piece was 3.77AA. This proves that the developer has a considerably high resistance unless it contains conductive zinc oxide.

Comparative Example 2 In the toner formulation of Example 1, 3% of conductive zinc oxide was added.
A red toner was obtained in the same manner as in Example 1 except that the amount was 0 parts by weight. Using this, a developer was prepared in the same manner as in Example 1. When we measured the amount of triboelectric charge, −
It was 8.1 μC/g.

In the copy test, initial 1. Do, 6 and F,
Do, 014, and a low contrast image with significant background fogging was obtained. Moreover, the copy quality was so severe that it could not be used in practical use due to double tailing and brush mark phenomena. The bias current was 0.25 ηA, and it was found that the resistance was low.

Comparative Example 3 A blue toner was obtained in the same manner as in Example 1 except that conductive zinc oxide was removed from the formulation in Example 2. Using this, a developer was prepared in the same manner as in Example 2. When the amount of triboelectric charge was measured, it was -19.0 μc/y. A copy test was conducted using this developer. A good blue copy image similar to that in Example 2 was obtained, but cleaning defects occurred in the 5 cm x 5 ci solid image. In the 2,000-sheet continuous copy test, initial 1. D was 1.10 mo and F, D was 0.002, but the 2000th 1. D
was 0.81 mm, and F and D were 0.003, resulting in a reduction in image density due to edge effects. In addition, local background fogging (approximately 0.020) occurred due to drum filming. The transfer efficiency was 8496. This is 95 in Example 2.
1196 is also a low value compared to %.

The piama current value is 7.9 μA at the initial stage and 200 μA.
At the 0th sheet, it was 5.0 μA. It has been demonstrated that a developer not containing conductive zinc oxide has high resistance.

Reference Example For reference, an experimental example of a black toner whose resistance value can be controlled using carbon black is shown below. 2 parts by weight of polypropylene (Viscol 550P, manufactured by Sanyo Chemical Co., Ltd.), 6 parts by weight of Carbon Bra Tsuku (Special Black 74, manufactured by Degussa Corporation), 4 parts by weight of Moshite oil-soluble dye (Subiron Bra Tsuku TOH, manufactured by Hodogaya Chemical Co., Ltd.) A black toner consisting of parts by weight was prepared in the same manner as in Example 1. The amount of charge (
It was -19.0 μc/y. In a 2,000-sheet continuous copy test, initial 1. D is 1.41 mo and F, D
is 0.003, and the 2000th sheet is 1. D is 1.50
It also showed stable image maintenance characteristics with F, DIJ≦0004. Poor cleaning and drum filming were also common (not observed.The transfer efficiency of the developed toner was 94%.Also, when we measured the bias current value, the initial value was 13.9μA and the 2000th sheet The resistance was 13.47 AA. It can be seen that the resistance is properly controlled and stably 0. Generally, when using this developing device, the bias current value is 6 to 30 μA, preferably (or 10 μA). The values before and after are considered appropriate values.

The characteristics of each toner composition in the above examples, comparative examples, and reference examples are summarized in the table. With respect to cleaning performance, drum filming, and image maintenance performance, good results are indicated by 10, and poor performance is indicated by -. Transfer efficiency (calculated by the following formula)

Transfer efficiency (%) = (1 - (Cleaning recovered toner /
Toner consumption →) The agent is controlled to an appropriate resistance value and has excellent cleaning properties and drum filming prevention properties. This developer has no edge effect and has excellent resolution. A clear color image with high image density and no background fog can be obtained. It also exhibits excellent properties in terms of transfer efficiency.

that's all Applicant: Sanda Kogyo Co., Ltd. Agent: Patent Attorney Hidetaka Yamamoto

Claims (1)

[Claims] 1. Binder resin and tetraelectric oxidation 1. IIi Lead particles and at least one of a colored pigment and a colored dye. A color toner composition for electrophotography containing gold. 2. The magnetic zinc oxide particles have a unique abrasive resistance value of 1.
00 Ωm.