JP4139033B2 - Toner for developing electrostatic image and image forming method - Google Patents

Description

【００５１】
冷却管、撹拌器、ガス導入管及び温度計を取り付けた３Ｌのフラスコにイオン交換水及びモノマーを仕込む。その処方例は表１に実施例Ａ−１〜Ａ−２、比較例Ｂ−１〜Ｂ−２として記す。液は撹拌しながら加熱し、規定の反応温度まで昇温し反応を行った。得られた重合物は水洗いし、常温１０トールにて乾燥し、揮発分１％以下の粉状粉体を得た。
【００５２】
Ａ：トナー製法
表１の条件よりなる樹脂１００部、カルナウバワックス５部、カーボンブラック１０部、金属錯塩型染料２部を二本ロールで溶融混練した。混練条件は表２に示した。
【００５３】
Ｂ：現像剤作成方法
マグネタイト１００部と表２の実施例Ｔ１〜Ｔ４、比較例Ｔ５〜Ｔ８のトナー２部をターブラー混合し現像剤とした。
【００５４】
Ｃ：画像評価方法
Ｂで得られた現像剤をリコー製スピリオ７０００に搭載できるように改造したものを用いて画像評価を行った。なお、帯電チャージャーはコロナ放電式で印加電圧は５ＫＶ、帯電ローラーはＡＣ電圧で４００Ｖのものを、転写チャージャーはコロナ放電式で印加電圧は３ＫＶ、転写ローラーはＤＣ電圧で３００Ｖのものを用いた。
また、ローラー方式のほうがチャージャー方式よりも感光体に対するダメージが少なく好ましい。
【００５５】
いずれも画像率７％の標準画像を１０万枚印字後に下記の評価を行った。
画像ボケとは６００ｄｐｉの解像度で印字した細線を顕微鏡で拡大し、その再現性を段階的に１から５段階の段階見本を用いて評価したものである。
画像流れとは印字された文字の再現性を５段階の段階見本を用いて評価したものである。
地汚れとはランニング後に白べた画像を印字させたその濃度をマクベス濃度計により読み取ったものである。
【００５６】
【表２】

【００５７】
【発明の効果】
本発明（１）および（３）は、高温下においてもトナーによるＯＰＣ汚染がなく、画像欠陥のない良好な画像を得ることができる。
本発明（２）の樹脂を使用することにより、トナー中のスチレンオリゴマー量が１００ｐｐｍ以下のトナーを得ることができる。
本発明（４）の帯電工程を搭載することによりＯＰＣ汚染がさらに防止でき、画像欠陥のない良好な画像を得ることができる。
本発明（５）の転写工程を搭載することによりＯＰＣ汚染がさらに防止でき、画像欠陥のない良好な画像を得ることができる。
【図面の簡単な説明】
【図１】本発明を実施する画像形成装置の一例の説明図である。
【符号の説明】
１ ＯＰＣ感光体
２ 帯電器（コロナチャージ、帯電ブラシ、帯電ローラーなど）
ＯＰＣ表面電位を１００〜１０００Ｖに帯電
３ 画像読み取り装置（ポリゴンミラーを介し、レーザー光を露光）
４ 現像装置（磁性または非磁性一成分または二成分現像装置）
１００〜８００Ｖの現像ポテンシャル
５ 転写装置（接触式の場合、印加電圧１００〜１０００Ｖ、コロナ放電式の
場合は、１〜１０ＫＶ）
６ 転写紙除電装置
７ クリーナユニット
８ クリーニングブラシ、ローラー
９ 除電ランプ
１０ 転写紙進行方向 線速５０〜１０００ｍｍ／ｓｅｃ
１１ 定着ローラー １００〜２００℃に設定[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a toner and an image forming method for developing an electrostatic latent image formed on an organic photoreceptor.
[0002]
[Prior art]
Electrophotographic photoconductors have been put to practical use mainly for inorganic photoconductive materials such as selenium, zinc oxide, cadmium sulfide, and various selenium alloys, but in recent years they are inexpensive, excellent in workability and high quality. Organic electrophotographic photoreceptors (OPCs) using organic photoconductive materials that are environmentally friendly at the time of disposal have been put into practical use and are now mainstream. However, compared to inorganic photoreceptors, the problem with the OPC photoreceptor is that the charge transport layer is made of an organic polymer resin, and is subject to various environmental fluctuations in the copying machine. is there. One of the major factors is environmental fluctuations such as ozone, NOx and other acidic gases generated from the main charger or transfer charger. Due to the exposure to the acid gas, the charge transport layer CTL is decomposed on the surface of the charge transport layer CTL, the charge transport material CTM, and the binder, causing image blur. In addition, depending on the type of the charge generation material CGM, the acid gas causes a significant decrease in charge, resulting in a decrease in potential contrast and background contamination. Further, as one of the major factors, there is OPC contamination due to the developer electrostatically adhering on the sleeve of the developing section or the toner remaining on the photosensitive member in a minute amount after cleaning. OPC contamination by toner for a long time when the OPC photoreceptor is in contact with the developer electrostatically adhering on the sleeve of the developing section at a high temperature or the toner remaining on the photoreceptor in a minute amount after cleaning. As a result, the residual potential increases linearly, resulting in deterioration of image quality such as background smudges, image blurring, and image flow. The elucidation of this problem is becoming more and more important as the lifetime of OPC photoreceptors increases.
[0003]
JP-B-8-27552 discloses an electrophotography using a styrene copolymer (B) containing 0.01 to 1% by weight of a styrene copolymer oligomer (A) having a number average molecular weight of 1000 or less. The toner composition for use in the present invention is disclosed. The content of the styrenic copolymer oligomer is changed from 100 ppm to 10,000 ppm. If the amount is within this range, contamination of the organic photoreceptor (OPC) is caused. There is a problem that it is caused by repeating the development and transfer process for a long period of time. Particularly, the residual potential is increased sharply, and background stains and image blurring are likely to occur. This is considered to be because those substances enter the photoconductor and trap the charge to prevent the movement of the charge, and it is impossible to prevent the occurrence of image defects.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide an image forming method in which an electrostatic latent image is formed on an organic photoreceptor and the latent image is visualized by using a toner composed of at least a binder resin component and a colorant. In the situation where the OPC photosensitive member and the developer are in contact with each other for a long time, the toner that prevents the occurrence of image defects due to the toner in the developer contaminating the OPC and provides a stable image for a long time, and the image A forming method and a resin for toner are provided.
[0005]
[Means for Solving the Problems]
The present inventor forms an electrostatic latent image on an organic photoreceptor, and develops the latent image using a toner composed of at least a binder resin component and a colorant. As a result of investigating what is necessary as a characteristic of the toner in order to prevent the OPC from being contaminated by the toner in the developer even when the photosensitive member and the developer are in contact with each other for a long time, the binder of the toner in the developer is determined. It has been found that, by limiting the resin, there is no source of OPC contamination, and a toner that does not have OPC contamination can be provided for the above purpose.
[0006]
That is, this invention consists of the structure of following (1)-(4).
(1) A toner produced by a kneading and pulverizing method, comprising at least a binder resin component made of a styrene acrylic resin produced by a suspension polymerization method , and a colorant, wherein two amounts of styrene are used as the binder resin used alone styrene-acrylic resin which is characterized by containing the styrene oligomers from the body to the molecular weight 700 100ppm or less 0.1ppm or more styrene oligomers 100ppm or less 0.1ppm from dimer of styrene molecular weight of up to 700 the toner for developing electrostatic images which is characterized by containing more.
[0008]
( 2 ) An image forming method in which an electrostatic latent image is formed on an organic photoreceptor, and the latent image is visualized using a toner composed of at least a binder resin component and a colorant. An image forming method using the toner according to 1.
[0009]
( 3 ) A charging member is brought into contact with the member to be charged, a voltage is applied to the charging member from the outside, an electrostatic latent image is formed on the organic photoreceptor, and a toner composed of at least a binder resin component and a colorant is used. Then, in the image forming method for visualizing the latent image, the toner according to claim 1 is used as the toner.
[0010]
(4) an electrostatic latent image on the organic photoreceptor is developed with a developer, an image forming method for electrostatically transferring the developing image to the transfer material through the transfer step in which the organic photosensitive member and a transfer device is in contact with in the image forming method of the toner in the developer it is characterized in toner der Rukoto of claim 1, wherein.
[0011]
Hereinafter, the present invention will be described in more detail.
In an image forming method in which an electrostatic latent image is formed on an organic photoconductor, and the latent image is visualized using a toner composed of at least a binder resin component and a colorant, the OPC photoconductor is developed at a high temperature. As a result of analyzing the mechanism of OPC contamination caused by the toner in the developer under the condition that the developer has been in contact for a long time, the following new facts have been discovered. Here, high temperature means a temperature environment of 30 to 50 ° C.
[0012]
The basic layer structure of the OPC photoreceptor is composed of a conductive support, a charge generation layer CGL, and a charge transport layer CTL. In CGL, light is absorbed by the charge generation material CGM, and positive and negative charge carriers are generated.
[0013]
One of these carriers is injected into the CTL and the other into the conductive support by the electric field applied to the photosensitive layer. The carriers injected into the CTL move through the CTL to the CTL surface by an electric field, and erase the charge on the surface of the photoreceptor. In order for the photoconductor to exhibit a photoconductive function, it is necessary that charges are efficiently generated by light absorption, and the charges are transported quickly without trapping holes in the photosensitive layer. However, since the adhesiveness is good when the toner and OPC come into contact at high temperature, if there is a material having a double bond π electron donating system in the toner, OPC contamination by the toner occurs, and holes in the CTL are trapped. As a result, it has been found that the surface charge does not disappear and therefore a residual potential remains. Furthermore, it has been found that styrene oligomer has the greatest influence on the material having a double bond π electron donating system contained in the toner. This is considered to be due to the strongest electron donating property because holes are alternated between every other carbon in the molecular structure of the styrene oligomer, so that holes are easily trapped.
[0014]
The styrene oligomer in the present invention refers to a styrene dimer to a 20 mer, and does not include a styrene monomer. Since the styrene monomer has a low boiling point, if it is left at a high temperature of 30 to 50 ° C. for a long time, it will not volatilize and remain. In the case of an oligomer, it is considered that it does not volatilize in the temperature range of 30 to 50 ° C., and the organic material has high affinity with OPC, which causes OPC contamination.
Accordingly, the amount of styrene oligomer in the toner is preferably as small as possible, but if it is 100 ppm or less, there is no influence of OPC contamination by the toner.
[0015]
In addition, although the amount of styrene oligomer is 100 ppm or less, it is preferably 90 ppm to 0.1 ppm to make this range, so that OPC contamination is not caused, and the presence of a moderately low molecular weight substance exhibits flexibility, Durability against film scraping is improved. More preferably, it is 60 ppm to 1 ppm, particularly preferably 50 ppm to 5 ppm, and most preferably 30 ppm to 10 ppm.
[0016]
In particular, by containing a styrene oligomer within the above range, low molecular weight substances such as styrene oligomers enter into the resin state of the OPC film in a molecular state and are plasticized, thereby exhibiting flexibility and durability against film scraping. It will improve.
[0017]
In addition, the binder resin used in the present toner contains 100 ppm or less of styrene oligomer as a whole resin, whereby a toner having a styrene oligomer amount of 100 ppm or less can be obtained.
Further, by using a charging roller in the charging step, the voltage can be lowered and generation of ozone can be prevented, so that OPC contamination can be further prevented.
[0018]
In order to make the content of styrene oligomer 100 ppm, it is preferable to increase the reaction time in the polymerization reaction and to carry out the reaction at a high temperature. However, in view of economy, the suspension polymerization takes 5 to 20 hours. Preference is given to carrying out at 70 to 100 ° C.
[0019]
This amount can also be adjusted by controlling the kneading temperature in the toner production process, and the content of styrene oligomer can be 100 ppm by kneading at a high temperature.
Further, when the kneading temperature is 100 to 200 ° C., the dispersibility of the toner composition is improved.
[0020]
An example of the present invention will be described more specifically with reference to a screen. This image forming method is performed as follows.
FIG. 1 is a cross-sectional view of an image forming apparatus in which the image forming method of the present invention is implemented. Around the drum-shaped image carrier (1), a charging roller (2), a laser optical system (3), a developing roller (4), a transfer roller (5), a separation charger (6), a pre-cleaning charger (7), A cleaning roller (8) and a charge removal lamp (9) are disposed, and image formation is performed by the following operation. A series of image forming processes will be described as a negative-positive process.
[0021]
The image bearing member (1), which is a photoconductor (OPC) having an organic photoconductive layer, is neutralized by a neutralizing lamp (9), and is uniformly negatively charged (for example, −700 V) by a charging roller (2), and laser optical system A latent image is formed by the laser beam irradiated from (3) (exposure portion potential is about −100 V).
[0022]
Laser light is emitted from a semiconductor laser, and the surface of the image carrier (1) is scanned in the direction of the rotation axis of the image carrier (1) by a hexagonal polygon mirror (polygon) that rotates at high speed.
The latent image formed in this way is developed with a magnetic brush of the developing roller (4) (applied voltage is -550 V, for example) to form a toner image.
[0023]
On the other hand, the transfer paper (transfer material) (10) is fed from a paper feed mechanism (not shown) and is synchronized with the leading edge of the image by a pair of upper and lower registration rollers (not shown). And the transfer roller (5) to transfer the toner image. At this time, the transfer bias applied to the transfer roller (5) is, for example, about + 950V. Thereafter, the transfer paper (10) is separated from the image carrier (1) and then discharged as a copy through the fixing device (11).
[0024]
The quantification method of the styrene oligomer in this invention is shown. This quantification is quantified by gas chromatograph mass spectrometry (GC1MS method) with QP-5000 manufactured by Shimadzu Corporation. The measurement conditions are as follows.
[0025]
<Measurement conditions>
Ion source: EI 70 eV
Detector: Cylindrical quadrupole with brirod Off-axis secondary electron multiplier mass Range: M / Z 29-700
Column: DB-5
L = 30 m I.V. D = 0.25 mm Film = 0.25 μm
Column temperature: 50 ° C. (hold = 1 min) to 300 ° C. 10 ° C./min Temperature rising vaporization chamber temperature: 350 ° C.
Column pressure: He 100 (hold = 1 min) to 150
2kPa / min step-up [0026]
The form of the organic photoreceptor in the present invention will be described below.
Examples of the conductive substrate include metals such as aluminum and stainless steel; aluminum alloys, indium oxide-tin oxide alloys; plastics having a coating layer of the metal or the alloy; paper or plastics impregnated with conductive particles; Examples thereof include a cylindrical cylinder and a film formed of plastic.
[0027]
On these conductive substrates, the adhesion of the photosensitive layer, the improvement of coating properties, the protection of the substrate, the coating of defects on the substrate, the improvement of charge injection from the substrate, the protection against the electrical breakdown of the photosensitive layer, etc. An undercoat layer may be provided for the purpose. Undercoat layer is polyvinyl alcohol, poly-N-vinylimitazole, polyethylene oxide, ethyl cellulose, methyl cellulose, nitrocellulose, ethylene-acrylic acid copolymer, polyvinyl butyral, phenol resin, casein, polyamide, copolymer nylon, glue, gelatin , Polyurethane and aluminum oxide. The film thickness is usually 0.1 to 10 μm, preferably 0.1 to 3 μm.
[0028]
The charge generation layer is composed of organic substances such as azo pigments, phthalocyanine pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, squarylium dyes, pyrylium salts, thiopyrylium salts, triphenylmethane dyes; A charge generation material made of an inorganic material such as crystalline silicon is dispersed in a suitable binder and formed by coating or vapor deposition. Examples of the binder include polycarbonate resin, polyester resin, polyvinyl butyral resin, polystyrene resin, acrylic resin, methacrylic resin, phenol resin, silicone resin, epoxy resin, and vinyl acetate resin. The amount of binder contained in the charge generation layer is 80% by weight or less, preferably 0 to 40% by weight. The thickness of the charge generation layer is preferably 5 μm or less, particularly preferably 0.05 to 2 μm.
[0029]
The charge transport layer has a function of receiving charge carriers from the charge generation layer in the presence of an electric field and transporting them. The charge transport layer is formed by dissolving a charge transport material in a solvent together with a binder resin as required, and coating, and the film thickness is generally 5 to 40 μm. Examples of charge transport materials include polycyclic aromatic compounds having a structure such as biphenylene, anthracene, pyrene, and phenanthrene in the main chain or side chain; nitrogen-containing cyclic compounds such as indole, carbazole, oxadiazole, and pyrazoline; hydrazone compounds; Styryl compounds; inorganic compounds such as selenium, selenium-tellurium, amorphous silicon, and cadmium sulfide.
[0030]
Examples of binder resins for dispersing these charge transport materials include polycarbonate resins, polyester resins, polymethacrylic acid esters, polystyrene resins, acrylic resins, polyamide resins; organic photoconductive materials such as poly-N-vinylcarbazole and polyvinylanthracene. A functional polymer.
[0031]
A catch layer may be provided as the surface layer. Examples of the resin for the protective layer include polyester, polycarbonate, acrylic resin, epoxy resin, phenol resin, or a mixture of these resins and a curing agent. These may be used alone or in combination of two or more.
[0032]
As the styrenic binder resin used in the toner obtained by the present invention, all known resins can be used. For example, a homopolymer of styrene such as polystyrene, poly-p-styrene, polyvinyltoluene and the like, a styrene-p-chlorostyrene copolymer, a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, a styrene- Methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-methacrylic acid Butyl copolymer, styrene-α-chloromethacrylic acid methyl copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, Styrene-isoprene copolymer, styrene-malein Copolymer, a styrene - styrene copolymer and maleic acid ester copolymer or the like can be used.
In order to further expand the fixing temperature range, it is desirable to blend a polyester resin.
[0033]
The polyester resin used as a binder in the present invention is obtained by condensation polymerization of an alcohol component and a carboxylic acid component. Examples of the alcohol component used include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, , 3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol and other diols, 1,4-bis (hydroxymethyl) cyclohexane, bisphenol A, hydrogenated bisphenol A, and others Mention may be made of divalent alcohol monomers.
[0034]
Examples of the carboxylic acid component include maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, and malonic acid. And acid anhydrides or lower alkyl esters thereof, dimer of linolenic acid, and other divalent organic acid monomers.
[0035]
The polyester resin used in this study is not only a bifunctional monomer as described above, but also a trivalent or higher polycarboxylic acid as a carboxylic acid component by a trifunctional or higher polyfunctional monomer or its acid anhydride. It is a polymer containing a product. Examples of the trivalent or higher polyvalent carboxylic acid monomer that is such a polyfunctional monomer include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and 1.2,4- Cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl -2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, embol trimer acid and acid anhydrides thereof, and the like.
[0036]
The trihydric or higher polyhydric alcohol used in the present invention may be any one generally known as a trihydric or higher polyhydric alcohol. For example, glycerin, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, 1,1,1-trimethylolbutane, pentaerythritol, 1,1,2,2-tetramethylolethane, 1 1,3,3-tetramethylolpropane, sorbitol, polyvinyl alcohol and the like. These are used in one or a mixture of two or more.
[0037]
The production method for obtaining the polyester of the present invention is not particularly limited, and the esterification reaction can be carried out by a known method. The transesterification reaction can be carried out by a known method, and in this case, a known transesterification catalyst can be used. Examples thereof include magnesium acetate, zinc acetate, manganese acetate, calcium acetate, tin acetate, lead acetate, and titanium tetrabutoxide.
[0038]
The polycondensation reaction can be performed by a known method, and a known polymerization catalyst can be used. Specific examples include antimony trioxide and germanium dioxide.
[0039]
The binder resin mentioned above can be mixed with a colorant and / or magnetic powder and, if necessary, a charge control agent and other additives as appropriate, and can be mixed as appropriate to obtain an electrostatic image developing toner.
[0040]
As the colorant, conventionally known ones such as carbon black, iron oxide pigment, phthalocyanine blue, phthalocyanine green, rhodamine 6G cake, and watching red strontium can be used. The amount of the colorant contained in the toner is appropriately selected and used within the range of 1 to 60% by weight.
[0041]
As the charge control agent, a nigrosine dye, a fatty acid-modified nigrosine dye, a metal-containing nigrosine dye, a metal-containing fatty acid displacement nigrosine dye, a chromium complex of 3,5-di-tert-butylsalicylic acid, and the like can be used. In the toner, 0 to 20% by weight is used.
[0042]
As the mold release agent, a wax having a melting point of 70 ° C. to 170 ° C. is used. Specific examples of the release agent include carnauba wax, montan wax, sazol wax, paraffin wax, low molecular weight polyethylene, low molecular weight polypropylene, and ethylene-vinyl acetate copolymer. These are added to the toner in the range of 1 to 10% by weight.
[0043]
As other additives, silica powder, hydrophobic silica powder, polyolefin, paraffin wax, fluorocarbon compound, fatty acid ester, partially saponified fatty carbonate, fatty acid metal salt, and the like can be used. 0.1 to 5% by weight is used.
[0044]
The toner of the present invention can be used for both dry one-component developers and two-component developers. The magnetic material in the case of a one-component developer includes an alloy containing elements exhibiting ferromagnetism such as ferrite, magnetite and the like, iron, cobalt, nickel, etc. Examples of alloys that have become ferromagnetic by treatment, such as manganese-copper-aluminum or manganese-copper-type alloys called Heusler alloys containing manganese and copper, or chromium dioxide. it can. The magnetic material is uniformly dispersed in the binder resin in the form of fine powder having an average particle size of 0.3 to 30 μm. The content of the magnetic particles is 20 to 70% by weight, preferably 40 to 70% by weight in the toner.
[0045]
The toner in the two-component developer is composed mainly of a colorant, a binder resin, and a charge control agent, as is generally used.
[0046]
The toner composition according to the present invention is made by any well-known toner mixing method and pulverization method. For example, all ingredients are blended in predetermined amounts, mixed and pulverized to thoroughly mix all ingredients and then the resulting mixture is micronized. In other well-known methods of forming toner powder, the colorant, resin and solvent are ball milled and the toner formulation mixture is spray dried.
[0047]
In order to use the toner composition according to the present invention by a cascade development method, a magnetic brush development method, an O-shell development method, or the like, the composition must have an average particle size expressed by weight percentage of about 30 μm or less. Rather, it is desirable for this average particle size to be between about 4-20 μm to produce optimal results. A particle size slightly smaller than 1 μm is desirable for use in powder cloud development.
[0048]
Coated and uncoated carriers used in cascade development, magnetic brush development, C-shell development, etc. are well known, so that the toner powder adheres to and surrounds the carrier particles. The carrier particles may be formed of any suitable material so long as the toner powder acquires a charge of the opposite polarity to that of the carrier particles when the carrier particles are in intimate contact with the toner powder. Thus, the toner composition of the present invention is used in admixture with a conventional carrier to develop an electrostatic latent image on any suitable electrostatic latent image bearing surface including a conventional photoconductive surface. Is done.
[0049]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to these examples and comparative examples. Table 1 shows synthesis examples of vinyl resins.
[0050]
[Table 1]

[0051]
Charge ion exchange water and monomer into a 3 L flask equipped with a condenser, stirrer, gas inlet tube and thermometer. The formulation examples are shown in Table 1 as Examples A-1 to A-2 and Comparative Examples B-1 to B-2. The liquid was heated while stirring, and the temperature was raised to a prescribed reaction temperature to carry out the reaction. The obtained polymer was washed with water and dried at room temperature of 10 Torr to obtain a powdery powder having a volatile content of 1% or less.
[0052]
A: Toner manufacturing method 100 parts of a resin having the conditions shown in Table 1, 5 parts of carnauba wax, 10 parts of carbon black, and 2 parts of a metal complex dye were melt-kneaded with two rolls. The kneading conditions are shown in Table 2.
[0053]
B: Developer Preparation Method 100 parts of magnetite and 2 parts of toners of Examples T1 to T4 and Comparative Examples T5 to T8 in Table 2 were mixed by a tumbler to obtain a developer.
[0054]
C: Image evaluation was performed using a developer obtained by the image evaluation method B modified so that it can be mounted on a Ricoh Spirio 7000. The charging charger was a corona discharge type with an applied voltage of 5 KV, the charging roller was an AC voltage of 400 V, the transfer charger was a corona discharge type with an applied voltage of 3 KV, and the transfer roller was a DC voltage of 300 V.
In addition, the roller method is preferable to the charger method with less damage to the photoreceptor.
[0055]
In any case, the following evaluation was performed after printing 100,000 sheets of standard images with an image rate of 7%.
Image blur is a fine line printed at a resolution of 600 dpi, magnified with a microscope, and its reproducibility is evaluated step by step using 1 to 5 step samples.
Image flow is an evaluation of the reproducibility of printed characters using a five-step sample.
The background stain is a density obtained by printing a white image after running with a Macbeth densitometer.
[0056]
[Table 2]

[0057]
【The invention's effect】
In the present invention (1) and (3), there is no OPC contamination with toner even at high temperatures, and a good image without image defects can be obtained.
By using the resin of the present invention (2), a toner in which the amount of styrene oligomer in the toner is 100 ppm or less can be obtained.
By mounting the charging step of the present invention (4), OPC contamination can be further prevented and a good image free from image defects can be obtained.
By mounting the transfer step of the present invention (5), OPC contamination can be further prevented, and a good image free from image defects can be obtained.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of an example of an image forming apparatus that implements the present invention.
[Explanation of symbols]
1 OPC photoconductor 2 Charger (corona charge, charging brush, charging roller, etc.)
Charge OPC surface potential to 100-1000V 3 Image reading device (expose laser light through polygon mirror)
4. Developing device (magnetic or non-magnetic one-component or two-component developing device)
Development potential of 100 to 800 V 5 Transfer device (applied voltage 100 to 1000 V for contact type, 1 to 10 KV for corona discharge type)
6 Transfer paper static elimination device 7 Cleaner unit 8 Cleaning brush, roller 9 Static elimination lamp 10 Transfer paper traveling direction Linear velocity 50 to 1000 mm / sec
11 Fixing roller Set to 100-200 ° C

Claims (4)

A toner produced by a kneading and pulverizing method, comprising at least a binder resin component made of a styrene acrylic resin produced by a suspension polymerization method , and a colorant, and having a molecular weight from a dimer of styrene as the binder resin used alone styrene-acrylic resin which is characterized by containing up to 700 styrene oligomer 100ppm or less 0.1ppm or more, containing less 0.1ppm least 100ppm of styrene oligomer molecular weight of up to 700 from the dimer of styrene An electrostatic charge image developing toner. The image forming method for forming an electrostatic latent image on an organic photoreceptor and developing the latent image using a toner composed of at least a binder resin component and a colorant, as the toner according to claim 1. An image forming method using toner.   The charging member is brought into contact with the member to be charged, a voltage is applied to the charging member from the outside, an electrostatic latent image is formed on the organic photoreceptor, and a toner composed of at least a binder resin component and a colorant is used. An image forming method for developing a latent image, wherein the toner according to claim 1 is used as the toner. In an image forming method, an electrostatic latent image on an organic photoreceptor is developed with a developer, and the developed image is electrostatically transferred to a transfer material through a transfer process in which the organic photoreceptor and a transfer device are in contact with each other. the image forming method to which the toner in the developer is characterized in toner der Rukoto of claim 1, wherein.

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