JP4165640B2 - Positively charged non-magnetic one-component toner and developing method - Google Patents

Description

【００４２】
実施例４〜６および比較例３，４
原料として下記のものを使用した他は実施例１〜３および比較例１,２と同様にして、表２に示す組成の正帯電型非磁性一成分トナーを得た。
＜結着樹脂＞
（5）トーパス-ＴＢＧ：ティコナ社製の環状構造を有する酸変性ポリオレフィン樹脂の商品名（前記トーパス-ＴＢの酸変性タイプ）
＜帯電制御剤＞
・ＤＳ：α−シクロデキストリンにｐ−トルエンスルホン酸を反応させて得られたシクロデキストリンのトシル化物（トシル化率５０％）
・４級アンモニウム塩：ヘキストインダストリー社製の「COPY CHARGE PSY」
・イミダゾール
得られたトナーを用いて実施例１〜３および比較例１,２と同様にして連続複写を行い、非画像部のカブリを目視にて確認した。その結果を表２に示す。なお、表２において、比誘電率を除く、各成分の配合量は重量部で示す。
【表２】

【００４３】
【発明の効果】
本発明の正帯電型非磁性一成分トナーは、特定の組み合わせからなる環状構造を有するポリオレフィン樹脂を使用し、かつこれに特定の帯電制御剤を配合することにより、帯電安定性が改善され、カブリのない高画質・高解像度のトナー画像を得ることができ、しかも環境や人体に対して安全であるという効果がある。
【図面の簡単な説明】
【図１】本発明にかかる現像装置を示す概略図である。
【図２】本発明にかかる現像装置を示す概略図である。
【符号の説明】
１ 現像ローラ
３ 感光体
４ トナー
５ 現像域
６ 薄層化ブレード
７ 薄層化ローラ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a positively charged nonmagnetic one-component toner and a developing method suitable for use in electrophotography, particularly color electrophotography, applied to copying machines and printers.
[Prior art]
[0002]
Recently, copiers and printers are demanding higher resolution and clear high-speed printing without fogging. In particular, with the spread of color copiers and color printers, high-speed and high-quality printing is also required for color printing.
In order to obtain such a high-quality image, a one-component developer that does not deteriorate image quality due to carrier deterioration is more advantageous than a two-component developer that uses a carrier and toner. Furthermore, among single-component developers, non-magnetic single-component toners that do not contain magnetic materials are easier to apply to color toners and are cheaper than magnetic one-component toners that contain magnetic materials such as magnetite. There is an advantage that it can be manufactured.
[0003]
On the other hand, in the case of a photoconductor, particularly an organic photoconductor, a positively charged type photoconductor is preferable to a negatively charged type in order to realize high-quality printing. Further, the positively charged photosensitive member has advantages of higher charging stability and less ozone generated by corona discharge in the charging process than the negatively charged photosensitive member.
Therefore, in order to obtain an image with high image quality and little fog, a positively charged nonmagnetic one-component toner is desirable. In the case of a positively charged photoreceptor, the development in the printer is so-called reversal development in which toner is attached to the exposed portion, and the toner is attached to the charge removal portion from which charge has been removed by exposure. In order to form the toner, the charging property of the toner is the same as the charging property of the photoreceptor.
[0004]
By the way, so-called polymerized toner is attracting attention in order to perform high-quality color printing and the like. The polymerized toner is produced directly by a polymerization process, and unlike a toner obtained by a conventional kneading and pulverizing method, a toner having a uniform particle size distribution and a small particle size can be obtained.
[0005]
However, in the case of a styrene-acrylic resin or a polyester resin that is usually used as a binder resin for polymerized toner, there are concerns about the environmental impact and safety problems caused by the additives used. In particular, due to the recent increase in environmental awareness, toners are also strongly required to be safe for the environment and the human body.
As a resin excellent in safety to the environment and the human body, a polyolefin resin having a cyclic structure has attracted attention, and various toners using this as a binder resin have been proposed (Patent Documents 1 to 4 below). See).
[0006]
The polyolefin resin having the above cyclic structure is composed of carbon and hydrogen, and thus has an advantage of high safety to the environment and the human body. On the other hand, since the charging stability is poor, there is a drawback that fog is likely to occur. It was difficult to put it into practical use. For this reason, the actual situation is that toners using the above-mentioned polyolefin resin having a cyclic structure as a binder resin have hardly been put to practical use.
[0007]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-101631 [Patent Document 2]
JP 9-43891 A [Patent Document 3]
JP 2000-284528 A [Patent Document 4]
JP 2000-206732 A
[Problems to be solved by the invention]
Accordingly, a main object of the present invention is to provide a positively charged non-magnetic one-component toner that is highly safe for the environment and the human body and that can perform high-quality printing without fogging, and a developing method using the same. .
[0009]
Another object of the present invention is to provide a positively charged non-magnetic one-component color toner capable of high-speed and high-quality color printing and a developing method using the same.
[Means for Solving the Problems]
The present inventor preferably uses a positively charged non-magnetic one-component toner to perform high-quality printing without fogging, and considering the safety to the environment and the human body, the polyolefin having the above-described cyclic structure Since it is preferable to use a resin, intensive studies were made to use this polyolefin resin as a binder resin for a positively charged non-magnetic one-component toner. As a result, when the polyolefin resin having the cyclic structure as the binder resin is used in combination with the acid-modified polyolefin resin having the cyclic structure and a specific charge control agent is blended, the disadvantages of the polyolefin resin having the cyclic structure As a result, the present inventors have completed the present invention by finding new knowledge that the charging stability has been improved and high-quality printing without fogging is possible.
[0011]
That is, the positively chargeable non-magnetic one-component toner of the present invention is mainly composed of a binder resin, a charge control agent, a colorant and a fluidity-imparting agent, and the weight of the binder resin is 100 parts by weight. The binder resin contains 70 to 90 parts by weight of a polyolefin resin (A) having a cyclic structure and 0 to 20 parts by weight of an acid-modified polyolefin resin (B) having a cyclic structure, and the charge control The agent is characterized by being a styrene-acrylic copolymer containing a quaternary ammonium base or a tosylated product of cyclodextrin.
[0012]
The acid-modified polyolefin resin (B) was originally developed for negative and positively charged toners, but by mixing a small amount of such acid-modified polyolefin resin (B) with the polyolefin resin (A). In addition, the positive chargeability and electrical resistance of the toner are lowered, and thereby the charging stability is improved. Further, in addition to the use of such an acid-modified polyolefin resin (B), it is necessary to use the specific compound as a charge control agent, and the charge control agent is a quaternary ammonium salt that is usually used. If this is the case, fogging cannot be prevented.
[0013]
Further, the positively charged non-magnetic one-component color toner of the present invention mainly comprises a binder resin, a charge control agent, a colorant and a fluidity imparting agent, and the weight of the binder resin is 100 wt. The binder resin contains 70 to 90 parts by weight of a polyolefin resin (A) having a cyclic structure and 0 to 20 parts by weight of an acid-modified polyolefin resin (B) having a cyclic structure. The controlling agent is a quaternary ammonium base-containing styrene-acrylic copolymer or a cyclodextrin tosylate, and has a relative dielectric constant of 2.20 or less. When the relative permittivity is 2.20 or less, the charge rising speed in the positive charge is increased and the charge distribution is sharpened, so that high-quality and high-resolution color printing is possible.
[0014]
In the developing method of the present invention, the toner on the developing roller is formed into a uniform thin layer while frictionally charging the positively charged non-magnetic one-component toner between the thinning means and the developing roller. The electrostatic latent image carried on the photosensitive member in the developing area is visualized. Examples of the thinning means include a thinning blade and a thinning roller. The edge of the thinning blade or the thinning roller is pressed against the developing roller to frictionally charge the toner.
[0015]
In the usual one-component development method, the lower surface of the thinning blade is pressed against the developing roller, but in the present invention, the toner is frictionally charged by bringing the edge of the thinning blade into contact with the developing roller as described above. Yes. This is due to the fact that the toner of the present invention has high charging stability and quick charge rise. By bringing the edge of the thinning blade or the thinning roller into contact, there is an advantage that a thin film layer can be formed with a low load.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
As described above, the positively chargeable non-magnetic one-component toner of the present invention contains a binder resin, a charge control agent, a colorant, and a fluidity imparting agent as main components.
When the weight of the binder resin is 100 parts by weight, the binder resin comprises 70 to 90 parts by weight of a polyolefin resin (A) having a cyclic structure and an acid-modified polyolefin resin (B) having a cyclic structure 0 to 20 Part by weight is the main material. The polyolefin resin (A) having a cyclic structure is, for example, an α-olefin (acyclic olefin) such as ethylene, propylene, butylene and an alicyclic ring having a double bond such as cyclohexene, norbornene, tetracyclododecene, or cyclopentadiene. It is a copolymer with a formula compound. Since this copolymer is colorless and transparent and has high light transmittance, it is particularly suitable for use as a color toner. The polyolefin resin having this cyclic structure can be obtained, for example, by a polymerization method using a metallocene catalyst, a Ziegler catalyst or the like.
[0017]
The polyolefin resin (A) having a cyclic structure used in the present invention has a number average molecular weight of 1000 to 7500, preferably 3000 to 7500, measured by gel permeation chromatography (hereinafter abbreviated as GPC). Examples thereof include those having an average molecular weight in the range of 1000 to 60000, preferably 3000 to 55000. The polyolefin resin (A) may have a monodisperse molecular weight with a single peak, or may have a polydisperse molecular weight with two or more peaks.
[0018]
In the present invention, the polyolefin resin (A) having a cyclic structure is a monodisperse type (one peak) having a weight average molecular weight of 4000 to 6000 and a low molecular weight polyolefin having a cyclic structure, and a weight average molecular weight of 4000 to 50000. Any one of polydisperse type (usually 2 peaks) polydisperse molecular weight polyolefin having a cyclic structure is preferably used alone or a mixture of both. Examples of the former low-molecular-weight polyolefin include, for example, registered trademark Topas (TOPAS) -TM manufactured by ticona, and examples of the latter polydispersed molecular weight polyolefin include registered-trademark Topas (TOPAS) -TB manufactured by Ticona. It is done. The blending ratio of the low molecular weight polyolefin and the polydisperse molecular weight polyolefin is 90:10 to 10:90, preferably 50:20 to 50:50, by weight.
[0019]
The acid-modified polyolefin resin (B) having a cyclic structure is a polyolefin resin having a cyclic structure in which an acid group such as a carboxyl group is introduced into a molecule (for example, a cyclic portion). The molecular weight of the acid-modified polyolefin resin having a cyclic structure may be substantially the same as that of the polyolefin resin (A) having the cyclic structure. Examples of such an acid-modified polyolefin resin (B) include registered trademark Topas (TOPAS) -TMG or TOPAS-TBG manufactured by Ticona.
[0020]
When the blending amount of the polyolefin resin (A) having a cyclic structure is less than the above range, the chargeability at high temperature may be lowered, and high temperature offset and filming are likely to occur. When it exceeds the range, the positive chargeability becomes high and fog is likely to occur. On the other hand, when the compounding amount of the acid-modified polyolefin resin (B) having a cyclic structure is less than the above range, the polyolefin resin (A) is relatively increased, so that fog is likely to occur. When the amount is larger than the above range, the positive chargeability at high temperature may be lowered.
[0021]
In addition, the polyolefin resin (A) and the acid-modified polyolefin resin (B) having the above-mentioned cyclic structure have insufficient flexibility and bending strength, so that the toner image is easily peeled off when the paper on which the toner image is printed is folded. There is. For this reason, by adding an ethylene-vinyl acetate copolymer (EVA) as a binder resin, flexibility is imparted and the bending strength can be improved. The amount of ethylene-vinyl acetate copolymer added is suitably 2 to 15 parts by weight, preferably 3 to 10 parts by weight.
[0022]
In the present invention, a quaternary ammonium base-containing styrene-acrylic copolymer or a cyclodextrin tosylate is used as a charge control agent. If a quaternary ammonium salt or imidazole usually used for a positively charged toner is used as the charge control agent, fog may occur. The quaternary ammonium base-containing styrene-acrylic copolymer includes, for example, a monomer composed of styrene, α-methylstyrene or a combination thereof, di-lower alkylamino (meth) acrylate, and (meth) acrylic as necessary. It is produced by copolymerizing an acid lower alkyl ester in the presence of a polymerization initiator, and then quaternizing the obtained copolymer. Quaternization can be performed using, for example, p-toluenesulfonic acid lower alkyl ester. The quaternized copolymer may have a weight average molecular weight in the range of 2000 to 10,000. In addition, the said lower alkyl group means a C1-C6 alkyl group.
[0023]
Specific examples of the quaternary ammonium base-containing styrene-acrylic copolymer include butyl acrylate-N, N-diethyl-N-methyl-2- (methacryloyloxy) ethylammonium = p-toluenesulfonate / styrene copolymer Examples include coalescence. As this copolymer, for example, “Acrybase FCA-201-PS” manufactured by Fujikura Kasei Co., Ltd. can be used.
[0024]
The tosylated product of cyclodextrin is obtained by reacting α-, β- or γ-cyclodextrin with p-toluenesulfonic acid, and the hydroxyl group of cyclodextrin is converted to a tosyl group (p-toluenesulfonyl group). ). In this case, the tosylation rate is preferably 40% to 55%.
The blending amount of the charge control agent in the present invention is 0.5 to 5 parts by weight, preferably 1.0 to 3.0 parts by weight with respect to 100 parts by weight of the binder resin. When the blending amount of the charge control agent is less than this range, it is difficult to obtain the required positive chargeability, and there is a risk of causing a problem that the fixed image becomes unclear due to variation in the charge amount, and the photosensitive member becomes dirty. There is. On the other hand, when the blending amount of the charge control agent is larger than this range, there is a risk of causing problems such as a decrease in compatibility with the binder resin and the occurrence of fogging and offset.
[0025]
Other components constituting the toner of the present invention are a colorant, a wax, a fluidity imparting agent and the like. As the colorant, any pigment or dye usually used for color toners or the like can be used. Examples of such colorants include carbon black, nigrosine dye, aniline blue, calco oil blue, chrome yellow, ultramarine blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, Rose Bengal etc. are mentioned, These are used individually or in mixture of 2 or more types. These colorants are blended in a ratio sufficient to form a sufficient visible image, and are usually 1 to 20 parts by weight, preferably 2 to 10 parts by weight with respect to 100 parts by weight of the binder resin. It is good.
[0026]
As the wax, it is particularly preferable to use a positively charged wax. If a negatively charged wax is used, the image quality may be deteriorated. Examples of the positively charged wax include amide waxes such as behenic acid amide and ethylene bisstearyl amide. Such a wax serves to lower the melting start temperature of the toner and to improve the low-temperature fixability.
[0027]
Examples of the fluidity-imparting agent (external additive) include silica, alumina, titanium oxide, talc, clay, calcium carbonate and the like. Particularly, hydrophobic silica (BET specific surface area: 110 ± 20 m ² / g), alumina ( It is preferable to use at least two of BET specific surface area: 100 ± 15 m ² / g) and titanium oxide (BET specific surface area: 50 ± 10 m ² / g). These fluidity imparting agents function to control the fluidity of the toner and prevent fogging and filming. The fluidity-imparting agent is added at a ratio of 1.5 to 4 parts by weight with respect to 100 parts by weight of the toner particles. Examples of the surface treatment of the toner with the fluidity-imparting agent include stirrers such as a turbine stirrer, a Henschel mixer, and a super mixer.
[0028]
The toner of the present invention is prepared by mixing the above-mentioned materials excluding the fluidity-imparting agent with a mixing machine such as a Henschel mixer and a ball mill, and then heat-melting and kneading with a heating roller, a heating kneader, etc., and then pulverizing with a jet mill, a hammer mill, etc. The toner particles are obtained by pulverizing with a machine and classifying with a dry air classifier. The toner according to the present invention is obtained by surface-treating the toner particles with the above-described fluidity-imparting agent.
[0029]
The average particle diameter of the toner is preferably 5 to 8 μm. In the case of yellow, magenta, and cyan toners that are color toners, the average particle size should be 5 to 7.5 μm, and the proportion of the particle size of 4 μm or less in the toner particle size distribution is 30% or less, Preferably, it is 20% or less, and if it exceeds 30%, filming tends to occur on the developing roller. In the particle size distribution of the color toner, the proportion of the particle size of 12 μm or more is 3% or less, and preferably 11 μm or more is 0% in order to obtain a fine image quality.
[0030]
On the other hand, in the case of black toner, the average particle size is preferably 7.3 to 8 μm. In the particle size distribution of the black toner, the proportion of the particle size of 4 μm or less should be 30% or less, and preferably 20% or less. The proportion of 12 μm or more is 3% or less, and preferably 11 μm or more is 0% in order to obtain a fine image quality.
[0031]
Next, a developing method using a positively charged non-magnetic one-component toner as the obtained toner will be described. FIG. 1 shows a developing device according to the present invention. A developing roller 1 is provided with a part thereof exposed at the tip of a developing device 2 and faces a photosensitive drum 3 at an appropriate interval. The photoconductor drum 3 is an organic photoconductor having a positively charged photoconductive layer formed on the surface of a conductive substrate, and image exposure (indicated by an arrow L) is performed with the surface of the organic photoconductor charged. An electrostatic latent image is formed.
[0032]
A thinning blade 6 (thinning means) is disposed on the surface of the developing roller 1, and the toner 4 supplied onto the developing roller 1 is pressed against the developing roller 1, so that the thinning blade 6 and the developing roller are in contact with each other. A thin layer having a predetermined layer thickness is formed while being frictionally charged with 1. The toner 4 charged with frictional charging is carried and conveyed to the developing area 5 (developing nip) by the developing roller 1, and the electrostatic latent image carried on the surface of the photosensitive drum 3 is visualized in the developing area 5. Development is performed. At this time, the ratio between the surface speed of the developing roller and the surface speed of the photoreceptor is preferably in the range of 1.2 to 2.5. For this development, a developing bias is applied to the developing roller 1 from a DC power source so that the toner 4 on the developing roller 1 adheres well to the electrostatic latent image on the photosensitive drum 3. The electric resistance of the developing roller 1 is preferably 1 × 10 ⁶ to 1 × 10 ⁷ Ωcm. Since the development is reversal development, the toner 4 is attached to a portion where the charge is removed by image exposure of the photosensitive drum 3 to form a visible image.
The surface of the developing roller 1 and the thinning blade 6 in the present invention can be made of a semiconductive rubber material, such as semiconductive acrylonitrile-butadiene rubber (NBR), urethane rubber, silicon rubber, etc., and particularly NBR. Is preferably used. Further, the thinning blade 6 contacts the developing roller 1 at the edge to frictionally charge the toner 4.
[0033]
Since the color toner of the present invention has a relative dielectric constant of 2.2 or less, it has a characteristic that the rising speed of positive charge is fast, and the charge distribution is also sharp, which enables high image quality and high resolution. . On the other hand, in the case of black toner, the relative dielectric constant does not necessarily need to be 2.2 or less, and can be used even if it is about 2.6, for example. Incidentally, in the case of a negatively charged toner using a polyester resin as a binder resin, the relative dielectric constant is 2.83. The relative dielectric constant can be measured by, for example, a TR-10C type dielectric loss measuring apparatus manufactured by Ando Electric Co., Ltd.
[0034]
Further, the toner charge amount is preferably 10 to 40 μc / g on the developing roller, and when the toner charge amount is out of this range, fog occurs and transfer efficiency deteriorates. The transfer efficiency is preferably 85% or more.
[0035]
Next, a developing method when a thinning roller is used as the thinning means will be described. FIG. 2 shows another developing device according to the present invention. The developing roller 1 is provided with a part thereof exposed at the tip of the developing device 2 and faces the photosensitive drum 3 at an appropriate interval. A thinning roller 7 (thinning means) is disposed on the surface of the roller 1.
[0036]
The thinning roller 7 is rotationally driven by a rotational driving source (not shown), and the toner 4 supplied onto the developing roller 1 is pressed against the developing roller 1, so that the thinning roller 7 is interposed between the thinning roller 7 and the developing roller 1. A thin layer having a predetermined layer thickness is formed while being frictionally charged. The toner 4 charged with frictional charging is carried and conveyed to the developing area 5 (developing nip) by the developing roller 1, and the electrostatic latent image carried on the surface of the photosensitive drum 3 is visualized in the developing area 5. Development is performed. The ratio between the surface speed of the developing roller 1 and the surface speed of the thinning roller 7 is preferably in the range of 0.1 to 0.5.
[0037]
The thinning roller 7 can be formed of, for example, a metal material such as stainless steel at least on the peripheral surface. The rotation direction of the thinning roller 7 is the same as that of the developing roller 1. Further, the tip of a blade 8 (cleaning means) is in contact with the surface of the thinning roller 7 in order to scrape off the toner 4 adhering to the surface of the thinning roller 7. Others are the same as those in the above-described embodiment, and thus the same reference numerals are given and description thereof is omitted.
[0038]
【Example】
Hereinafter, the positively charged nonmagnetic one-component toner and the developing method of the present invention will be described in detail with reference to examples.
[0039]
Examples 1 to 3 and Comparative Examples 1 and 2
The following were used as raw materials for the production of positively charged nonmagnetic one-component toner.
<Binder resin>
(1) Topas-TM: trade name of polyolefin resin having a cyclic structure manufactured by Ticona, Inc. (one peak)
Weight average molecular weight 4000-6000
Number average molecular weight 2000-3000
(2) Topas-TB: Trade name of polyolefin resin having a cyclic structure manufactured by Ticona, Inc. (2 peaks)
Weight average molecular weight 4000-50000
Number average molecular weight 2000-5000
(3) Topas-TMG: Trade name of acid-modified polyolefin resin having a cyclic structure manufactured by Ticona (Topas-TM acid-modified type)
(4) EVA: Ethylene-vinyl acetate resin (trade name: EV 250) manufactured by Mitsui DuPont Polychemical Co., Ltd.
<Charge control agent>
FCA-201: quaternary ammonium base-containing styrene-acrylic copolymer, abbreviation of “Acrybase FCA-201-PS” manufactured by Fujikura Kasei Co., Ltd.
<Colorant>
Yellow pigment: PY 180 (weak negative polarity)
<Wax>
Amide WAX: Fatty acid amide (trade name: BNT) manufactured by Nippon Seika Co., Ltd.
[0040]
The above components were mixed in a ratio shown in Table 1 using a Henschel mixer, melted and kneaded at 120 ° C. with a heating kneader, and the resulting kneaded product was pulverized with a jet mill and classified with a dry air classifier. As a result, toner particles having an average particle diameter of 7.0 μm were obtained. To 100 parts by weight of the toner particles, 2.5 parts by weight of a fluidity-imparting agent was added and mixed with a Henschel mixer to obtain a positively chargeable toner. The fluidity imparting agent used was hydrophobic silica (HVK2050 manufactured by Clariant), alumina (alumina C manufactured by Nippon Aerosil Co., Ltd.) and titanium oxide (STT65-CS manufactured by Titanium Industry Co., Ltd.) in a weight ratio. It is a mixture of 1.5: 0.5: 1.0. The relative dielectric constant of this toner was measured with a TR-10C type dielectric loss measuring device manufactured by Ando Electric. The results are also shown in Table 1.
[0041]
Using the obtained toner, positively charged nonmagnetic one-component development was performed with a developing device as shown in FIG. 1 (printer manufactured by T & M Co., Ltd.). Development conditions are as follows.
(A) Developing roller: NBR, rotational speed 450 mm / second, bias power supply 300 V
(B) Supply roller: manufactured by NBR, per edge of the developing roller 1, bias power supply 450V
(C) Photoconductor: Organic photoconductor whose photoconductive layer is a positively charged single layer type, rotational speed 300 mm / sec. (D) Thinning blade 6: NBR, per edge on developing roller 1, bias power supply 300V
(E) Static elimination sheet: Applied voltage 200V
Make a continuous copy of 100,000 sheets with the above-mentioned copying machine, visually check for fog in the non-image area, evaluate that there is no fogging, △ if there is a little fogging, and evaluate x if there is much fogging. did. The results are shown in Table 1. In Table 1, the amount of each component, excluding the relative dielectric constant, is shown in parts by weight.
[Table 1]

[0042]
Examples 4 to 6 and Comparative Examples 3 and 4
A positively charged nonmagnetic one-component toner having the composition shown in Table 2 was obtained in the same manner as in Examples 1 to 3 and Comparative Examples 1 and 2 except that the following materials were used.
<Binder resin>
(5) Topas-TBG: trade name of acid-modified polyolefin resin having a cyclic structure manufactured by Ticona (Topas-TB acid-modified type)
<Charge control agent>
DS: Tosylated product of cyclodextrin obtained by reacting α-cyclodextrin with p-toluenesulfonic acid (tosylation rate 50%)
・ Quaternary ammonium salt: “COPY CHARGE PSY” manufactured by Hoechst Industry
-Imidazole Continuous copying was carried out in the same manner as in Examples 1 to 3 and Comparative Examples 1 and 2 using the obtained toner, and the fog in the non-image area was visually confirmed. The results are shown in Table 2. In Table 2, the amount of each component, excluding the relative dielectric constant, is expressed in parts by weight.
[Table 2]

[0043]
【The invention's effect】
The positively chargeable non-magnetic one-component toner of the present invention uses a polyolefin resin having a cyclic structure composed of a specific combination, and by adding a specific charge control agent thereto, the charge stability is improved, and the fog is corrected. High-definition and high-resolution toner images can be obtained, and it is safe for the environment and the human body.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a developing device according to the present invention.
FIG. 2 is a schematic view showing a developing device according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Developing roller 3 Photoconductor 4 Toner 5 Developing area 6 Thinning blade 7 Thinning roller

Claims (5)

A positively charged non-magnetic one-component toner mainly composed of a binder resin, a charge control agent, a colorant and a fluidity-imparting agent,
When the weight of the binder resin is 100 parts by weight, the binder resin includes 70 to 90 parts by weight of a polyolefin resin (A) having a cyclic structure, and 0 to 20 acid-modified polyolefin resins (B) having a cyclic structure. Containing a weight part and the balance made of an ethylene-vinyl acetate copolymer,
The charge control agent is a quaternary ammonium base-containing styrene-acrylic copolymer or a cyclodextrin tosylate, and the amount of the charge control agent is 0.5 parts by weight with respect to 100 parts by weight of the binder resin. A positively charged non-magnetic one-component toner characterized by being less than 5 parts by weight. A positively charged non-magnetic one-component color toner mainly composed of a binder resin, a charge control agent, a colorant and a fluidity-imparting agent,
When the weight of the binder resin is 100 parts by weight, the binder resin includes 70 to 90 parts by weight of a polyolefin resin (A) having a cyclic structure, and 0 to 20 acid-modified polyolefin resins (B) having a cyclic structure. Containing a weight part and the balance made of an ethylene-vinyl acetate copolymer,
The charge control agent is a quaternary ammonium base-containing styrene-acrylic copolymer or a cyclodextrin tosylate, and the amount of the charge control agent is 0.5 parts by weight with respect to 100 parts by weight of the binder resin. And less than 5 parts by weight,
A positively charged non-magnetic one-component color toner having a relative dielectric constant of 2.20 or less. While the toner according to claim 1 or 2 is frictionally charged between the thinning means and the developing roller, the toner on the developing roller is formed in a thin layer and is carried and conveyed to the developing area. A developing method characterized in that an electrostatic latent image carried on a surface is visualized. 4. The developing method according to claim 3, wherein the thinning means is a thinning blade or a thinning roller. 5. The developing method according to claim 3, wherein an edge of the thinning blade or a thinning roller is brought into pressure contact with the developing roller to frictionally charge the toner.

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