JP2008070765A - Image forming method and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming method capable of forming an image with preferable developing property, transfer property and fixing property by a sphered toner small in particle size, and obtaining an excellent cleaning property with a simple configuration. <P>SOLUTION: The image forming method comprises: at least a step of developing an electrostatic latent image on an image carrier with a two-component developer; and a step of cleaning the toner on the image carrier with a cleaning blade. In the developing step, a developer is composed of the toner, in which the weight average particle diameter of the toner incorporated in the initial developer is smaller than that of a replenishing toner, and the toner covering ratio of the initial developer to the carrier of the developer is 55 to 75%. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming method using an electrophotographic process, and more particularly to an image forming method that does not cause a cleaning failure on an image carrier even when a small particle size and spherical toner is used. The present invention also relates to an image forming apparatus, a process cartridge, and a toner having a suitable configuration for executing this image forming method.

  In an image forming method using an electrophotographic process, the surface of a photoconductor, which is an image carrier, is uniformly charged, and then exposed to produce an electrostatic latent image, and the electrostatic latent image is developed with toner particles. An image is formed, and the toner image is transferred to a transfer paper or the like to form an image. Since there is toner remaining on the surface of the photoreceptor after the transfer process without being transferred to transfer paper or the like, a cleaning process is provided prior to the next image forming process to clean the surface of the photoreceptor. Various means using a fur brush, a magnetic brush, a rubber blade, etc. have been proposed as the cleaning means, but the means for scraping the remaining toner by rubbing the surface of the photoreceptor with the rubber blade is an inexpensive and simple configuration. Therefore, it is widely used.

On the other hand, in recent years, there has been an increasing demand for higher image quality, and in order to realize particularly high-definition color image formation, toner particles are being made smaller and spherical. The reproducibility of dots is improved by reducing the particle size, and the developability and transferability can be improved by making the particles spherical. Since it is very difficult to produce such a small particle size and spherical toner by the conventional kneading and pulverization method, the polymerization produced by suspension polymerization method, emulsion polymerization method, dispersion polymerization method, etc. Toner is being adopted.
However, when the particle size of the toner is reduced to several μm or less, non-electrostatic adhesion force such as van der Waals force acting between the toner and the photosensitive member increases with respect to its own weight. Becomes worse and it is difficult to clean the blade.
Further, since the spheroidized toner rolls without being caught by the edge of the rubber blade, it easily slips between the photoreceptor and the rubber blade, and the blade cleaning is similarly difficult.

To date, in order to achieve good blade cleaning properties, small-sized irregular shaped toners have been proposed. As such a toner, for example, polymer particles are dispersed in an aqueous medium, a hydrophilic / hydrophobic organic solvent is added, the particles are associated with each other, and the particles are fused with each other by subsequent heat treatment to produce a toner. A method or the like has been proposed (see, for example, Patent Document 1). However, such an irregular toner improves the cleaning property, but there is a problem that it is difficult to achieve both properties, such as the better transferability and fixing property are sacrificed closer to a spherical shape.
As a toner that achieves both the cleaning property of the irregular toner and the transfer property of the spherical toner, a toner in which the irregular toner and the spherical toner are mixed at a spherical toner ratio of 20% or less has been proposed (see Patent Document 2). .) However, in this toner, the ratio of the spherical toner is small, so that the transfer rate is lower than that of the spherical toner.

JP-A-5-265252 JP-A-8-95286

  In view of the above problems, the present invention forms an image with good developability, transferability, and fixability by using a toner having a small particle size and a spherical shape, and also realizes excellent cleaning properties by a simple configuration. It is an object to provide an image forming method.

  In order to solve the above problems, the present inventor disclosed in Japanese Patent Application Laid-Open No. 2005-49437 at least a step of developing with a developer containing an electrostatic latent image toner on an image carrier, and a toner on the image carrier. In the image forming method including the step of cleaning the toner with a cleaning blade, the image forming method using a toner having a weight average particle diameter smaller than that of the toner contained in the initial developer as a replenishment toner has been proposed. With such a configuration, the toner particle size of the initial agent is increased to prevent the toner from slipping from the tip of the cleaning blade, thereby maintaining good cleaning properties. This is related to the present invention.

The above problems are solved by the present invention of the following items (1) to (22).
“(1) In the image forming method including at least the step of developing the electrostatic latent image on the image carrier with a two-component developer, and the step of cleaning the toner on the image carrier with a cleaning blade, The weight average particle diameter of the toner contained in the initial developer is smaller than the replenishment toner, and the toner coverage of the initial developer with respect to the carrier of the developer is 55 to 75%. Forming method.
(2) The weight average particle diameter of the toner contained in the initial developer used in the developing step is 4.0 to 7.0 μm, and the weight average particle diameter of the replenishing toner is 5.0 to 9.5 μm. The image forming method according to item (1), characterized in that it is characterized in that:
(3) The image formation according to item (1) or (2), wherein the average circularity of the toner contained in the initial developer used in the development step is 0.93 or less. Method.
(4) In any one of (1) to (3), the method includes a toner recycling step in which the toner collected in the cleaning step is returned to the developer in the developing step and reused. Image forming method.
(5) The toner contained in the initial developer used in the developing step contains a charge control agent on the surface, and the charge control agent is an azo metal complex compound, a quaternary ammonium salt, or a fluorinated quaternary quaternary. The image forming method as described in (4) above, wherein the image forming method is selected from the group consisting of ammonium salts and salicylic acid metal complex compounds.
(6) The toner particles of the replenishing toner used in the developing step have a weight average particle diameter of 5.0 to 9.5 μm and a ratio between the weight average particle diameter (D4) and the number average particle diameter (Dn). (D4 / Dn) is in the range of 1.00 to 1.40. The image forming method as described in any one of (1) to (5) above.
(7) The toner particles of the replenishing toner used in the developing step have an average circularity of 0.94 or more, and any one of (1) to (6) above Image forming method.
(8) The toner particles of the replenishing toner used in the developing step have a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180. The image forming method according to any one of (1) to (7).
(9) The replenishing toner used in the developing step is a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent are dispersed in an organic solvent. Any of (1) to (8) above, which is obtained by dispersing and emulsifying in the form of droplets in an aqueous medium, and crosslinking and / or extending the reaction. The image forming method described.
(10) The toner particles of the replenishing toner used in the developing step have a substantially spherical shape, and the shape is defined by a major axis r1, a minor axis r2, and a thickness r3 (provided that r1 ≧ r2 ≧ r3 The ratio of the major axis r1 to the minor axis r2 (r2 / r1) is in the range of 0.5 to 1.0, and the ratio of the thickness r3 to the minor axis r2 (r3 / r2) is 0. The image forming method according to any one of (1) to (9), wherein the image forming method is in a range of 7 to 1.0.
(11) The developing process is performed a plurality of times on a single image carrier corresponding to the toners of a plurality of colors, and after each developing process is completed, a toner image is sequentially transferred onto the transfer medium and superimposed. The image forming method according to any one of (4) to (10), wherein the image forming method includes:
(12) A primary transfer step of transferring a plurality of color toner images formed on a single or a plurality of image carriers onto an intermediate transfer member, and cleaning the toner on the intermediate transfer member using a cleaning blade. The image forming method according to any one of items (4) to (10), further comprising: a step.
(13) Item (11) or (12), wherein the toner particles contained in the initial developer used in the developing means have a weight average particle diameter of 4.0 to 7.0 μm. The image forming method described in the item).
(14) Item (11) or Item (12) is characterized in that the average circularity of the toner particles of the toner contained in the initial developer used in the developing means is 0.93 or less. Image forming method.
(15) In an image forming apparatus having at least developing means for developing an electrostatic latent image on an image carrier with a two-component developer and cleaning means for cleaning toner on the image carrier with a cleaning blade In the developing means, the weight average particle diameter of the toner contained in the initial developer is made of a developer smaller than the replenishment toner, and the toner coverage of the initial developer with respect to the carrier of the developer is 55 to 75%, A plurality of the developing means are provided corresponding to a plurality of colors of toner on the single image carrier, and further have transfer means for transferring and superimposing the toner images on the transfer target sequentially after completion of each development. An image forming apparatus.
(16) In an image forming apparatus having at least developing means for developing an electrostatic latent image on an image carrier with a two-component developer and cleaning means for cleaning the toner on the image carrier with a cleaning blade In the developing means, the weight average particle diameter of the toner contained in the initial developer is made of a developer smaller than the replenishment toner, and the toner coverage of the initial developer with respect to the carrier of the developer is 55 to 75%, Primary transfer means for transferring a plurality of color toner images formed on a single or a plurality of image carriers onto an intermediate transfer body, and cleaning means for cleaning the toner on the intermediate transfer body using a cleaning blade And an image forming apparatus.
(17) In a process cartridge in which an image carrier and at least one unit selected from a charging unit, a developing unit, and a cleaning unit are integrally supported and are detachably formed in an image forming apparatus, the process cartridge includes: The image forming apparatus according to the item (15) or the item (16) is integrally supported by including at least the image carrier and the developing unit, and is detachably formed with respect to the image forming apparatus. Feature process cartridge.
(18) A toner used in a developing process of an electrophotographic process, wherein the toner is a replenishing toner used in the developing process of the image forming method according to any one of claims 1 to 8, and The weight average particle diameter of the particles is 3.0 to 7.0 μm, and the ratio (D4 / Dn) of the weight average particle diameter (D4) to the number average particle diameter (Dn) is in the range of 1.00 to 1.40. A toner characterized by being.
(19) The toner according to (18), wherein the toner particles have an average circularity of 0.94 or more.
(20) The toner particles of the toner, wherein the shape factor SF-1 is in the range of 100 to 180, and the shape factor SF-2 is in the range of 100 to 180. The toner according to item (19).
(21) In the toner, a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent is dispersed in an organic solvent is formed into droplets in an aqueous medium. The toner according to any one of items (18) to (20), wherein the toner is obtained by dispersing and emulsifying the toner and performing a crosslinking and / or elongation reaction.
(22) The toner particles of the toner have a substantially spherical shape, and the shape is defined by a major axis r1, a minor axis r2, and a thickness r3 (where r1 ≧ r2 ≧ r3), and the major axis r1. The ratio (r2 / r1) to the minor axis r2 is in the range of 0.5 to 1.0, and the ratio (r3 / r2) of the thickness r3 to the minor axis r2 is in the range of 0.7 to 1.0. The toner according to any one of (18) to (21), wherein the toner is present.

That is,
1. Instead of using large particles to block, the toner particle size of the initial agent is smaller than that of the replenishing toner, and the toner particles packed in the tip of the cleaning blade are not transferred in the transfer process. (Toner particle size of initial agent <replenished toner particle size) is blocked. “If the blade tip is packed with a small particle size toner, it is difficult to create a gap between the photoreceptor and the blade tip”, so it can be confirmed that there is very little opportunity for the toner to slip through the tip of the cleaning blade, and that the cleaning property is kept good. The present invention is based on such a philosophy. The toner coverage of the initial developer with respect to the developer carrier is 55 to 75%. Since the toner particle size of the initial agent is small, the surface area of the toner is increased, and the Q / M is increased by stirring with the carrier. As a result, the image density decreases as Q / M increases. Further, the transferability of the toner is deteriorated. In order to prevent the image density from being lowered and to improve the transferability of the toner, the toner coverage of the initial developer with respect to the carrier is set to 55 to 75%. When the toner coverage is less than 55%, there is no problem with toner scattering and dirt, but the image density is low. Also, toner transferability is not good. However, when the toner coverage exceeds 75%, the image density increases, but the amount of floating toner that cannot be fully charged with the carrier increases, and toner scattering and background contamination occur, resulting in extremely poor image quality. The coverage of the toner with respect to the carrier of the normal initial agent is set to about 40 to 50%. As the toner particle size of the initial agent is reduced, the toner coverage is set to a high value such as 55 to 75%. In the present invention, the coverage of the toner with respect to the carrier was obtained from the following formula (A) with reference to Japanese Patent No. 3493473.

・ＴＣ＝トナー濃度（％）
・ρ１＝トナーの真比重
・ρ２＝キャリアの真比重
・ｒ１＝トナーの体積平均粒径（μｍ）
・ｒ２＝キャリアの体積平均粒径
上式（Ａ）中の（１００−ＴＣ）はキャリア量に相当する。
２．現像工程で使用される初期現像剤に含まれるトナーの重量平均粒径は４．０〜７．０μｍで、補給トナーの重量平均粒径は５．０〜９．５μｍで、クリーニング性及び画像品質がより良好になる。
３．初期現像剤に含まれるトナーの平均円形度は０．９３以下にしてトナーのすり抜けを防止すると、クリーニング性及び画像品質がより良好になる。
４．クリーニング工程で回収されたトナーを現像工程の現像剤に戻して再使用するトナーリサイクル工程を含み、廃棄トナーは極力、減らすようにすることが好ましい。
５．初期現像剤に含まれるトナーは、表面に荷電制御剤を含有してなり、該荷電制御剤が、アゾ金属錯体化合物、４級アンモニウム塩、含フッ素４級アンモニウム塩、サリチル酸金属錯体化合物を含有すると、画像品質がより良好になる。
６．現像工程で使用される補給用トナーのトナー粒子は、重量平均粒径が５．０〜９．５μｍで、重量平均粒径（Ｄ４）と個数平均粒径（Ｄｎ）との比（Ｄ４／Ｄｎ）が１．００〜１．４０の範囲にあることで、画像品質がより良好になる。
７．現像工程で使用される補給用トナーは、トナー粒子の平均円形度が０．９４以上であると、画像品質がより良好になる。
８．現像工程で使用される補給用トナーは、トナー粒子の形状係数ＳＦ−１が１００〜１８０の範囲にあり、形状係数ＳＦ−２が１００〜１８０の範囲にあることで、画像品質がより良好になる。
９．現像工程で使用される補給用トナーは、少なくとも、窒素原子を含む官能基を有するポリエステルプレポリマー、ポリエステル、着色剤、離型剤とを有機溶媒中に分散させたトナー材料液を、水系媒体中で液滴状に分散・乳化処理し、架橋及び／又は伸長反応させて得られたものであることで画像品質がより良好になる。
１０．現像工程で使用される補給用トナーのトナー粒子は、略球形状であり、その形状が長軸ｒ１、短軸ｒ２、厚さｒ３で規定され（但し、ｒ１≧ｒ２≧ｒ３とする。）、長軸ｒ１と短軸ｒ２との比（ｒ２／ｒ１）が０．５〜１．０の範囲にあり、厚さｒ３と短軸ｒ２との比（ｒ３／ｒ２）が０．７〜１．０の範囲にあることで、画像品質がより良好になる。
１１．現像工程は単一の像担持体上で複数色のトナーに対応して複数回行われ（または、単一の像担持体上で複数色のトナーに対応して複数の現像手段を有し）、各現像の終了後、順次被転写体上にトナー像を転写して重畳する転写工程（または転写手段）を有することで、クリーニング性及び画像品質がより良好になる。
１２．単一もしくは複数の像担持体上で形成された複数色のトナー像を中間転写体上に転写する一次転写工程（又は一次転写手段）と、該中間転写体上のトナーはクリーニングブレードを用いてクリーニングする工程（またはクリーニング手段）を有することで、クリーニング性及び画像品質が良好になる。
１３．現像手段で使用される初期現像剤に含まれるトナー粒子の重量平均粒径は４．０〜７．０μｍであることで、クリーニング性及び画像品質がより良好になる。
１４．現像手段で使用される初期現像剤に含まれるトナーのトナー粒子の平均円形度は０．９３以下であることで、クリーニング性及び画像品質が良好になる。

TC = toner concentration (%)
Ρ1 = true specific gravity of toner ρ2 = true specific gravity of carrier r1 = volume average particle diameter of toner (μm)
R2 = volume average particle diameter of carrier (100−TC) in the above formula (A) corresponds to the amount of carrier.
2. The toner included in the initial developer used in the development process has a weight average particle diameter of 4.0 to 7.0 μm, and the replenishment toner has a weight average particle diameter of 5.0 to 9.5 μm. Will be better.
3. When the average circularity of the toner contained in the initial developer is set to 0.93 or less to prevent the toner from slipping through, the cleaning property and the image quality are improved.
4). It is preferable to reduce the waste toner as much as possible, including a toner recycling step in which the toner collected in the cleaning step is returned to the developer in the development step and reused.
5. The toner included in the initial developer contains a charge control agent on the surface, and the charge control agent contains an azo metal complex compound, a quaternary ammonium salt, a fluorinated quaternary ammonium salt, and a salicylic acid metal complex compound. , The image quality will be better.
6). The toner particles of the replenishing toner used in the development step have a weight average particle diameter of 5.0 to 9.5 μm and a ratio of the weight average particle diameter (D4) to the number average particle diameter (Dn) (D4 / Dn ) Is in the range of 1.00 to 1.40, the image quality becomes better.
7). When the average circularity of the toner particles is 0.94 or more, the image quality of the replenishing toner used in the development process becomes better.
8). The replenishment toner used in the development process has a toner particle shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180, so that the image quality is improved. Become.
9. The replenishment toner used in the development step is a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent is dispersed in an organic solvent. The image quality is improved by being obtained by dispersing and emulsifying in the form of droplets, and crosslinking and / or elongation reaction.
10. The toner particles of the replenishing toner used in the development process have a substantially spherical shape, and the shape is defined by a major axis r1, a minor axis r2, and a thickness r3 (provided that r1 ≧ r2 ≧ r3). The ratio of the major axis r1 to the minor axis r2 (r2 / r1) is in the range of 0.5 to 1.0, and the ratio of the thickness r3 to the minor axis r2 (r3 / r2) is 0.7 to 1. By being in the range of 0, the image quality becomes better.
11. The development process is performed a plurality of times on a single image carrier corresponding to a plurality of color toners (or a plurality of developing means corresponding to a plurality of color toners on a single image carrier). After the completion of each development, a cleaning process (or a transfer unit) that sequentially transfers and superimposes the toner images on the transfer target body improves the cleaning property and the image quality.
12 A primary transfer step (or primary transfer means) for transferring a plurality of color toner images formed on a single or a plurality of image carriers onto an intermediate transfer member, and toner on the intermediate transfer member using a cleaning blade By having a cleaning step (or cleaning means), the cleaning property and the image quality are improved.
13. The toner particles contained in the initial developer used in the developing means have a weight average particle size of 4.0 to 7.0 μm, so that the cleaning property and the image quality are improved.
14 When the average circularity of the toner particles of the toner contained in the initial developer used in the developing unit is 0.93 or less, the cleaning property and the image quality are improved.

  As will be apparent from the following detailed and specific description, the present invention provides an image forming method capable of maintaining good blade cleaning performance with a simple configuration even in image formation using a small particle size and spherical toner. be able to. This eliminates the problem of poor cleaning when using a small particle size, spherical toner, has excellent developability, transferability, fixability, and can form a high-quality, high-definition image. It plays.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram of an image forming apparatus according to a first embodiment of the present invention. A main charger (2) for charging the surface of the photosensitive drum (1) around the photosensitive drum (1) as an image carrier, and development for developing an electrostatic latent image formed on the surface of the photosensitive drum (1). Means (4), a transfer charger (5a) for charging the transfer paper when the toner image on the photosensitive drum (1) is transferred to the transfer paper, and the transfer paper on which the toner image has been transferred on the surface of the photosensitive drum (1) A separation charger (5b) that performs charging for separation from the toner and a cleaning means (8) that cleans residual toner on the photosensitive drum (1) are disposed.

As the photoreceptor (1), amorphous compounds having photoconductivity, amorphous metals such as amorphous selenium, and organic compounds such as bisazo pigments and phthalocyanine pigments can be used. In consideration of the environment and post-treatment after use, it is preferable to use a photoreceptor made of an organic compound.
Although the corona main charger (2) is shown as means for charging the photosensitive drum (1), a roller method, a brush method, a blade method or the like may be used.
Further, exposure means (not shown) for forming an electrostatic latent image by scanning exposure light (L) on the surface of the charged photosensitive drum (1) is provided.
As the transfer means, means that is not in contact with the transfer paper by the transfer charger (5a) and the separation charger (5b) is used, but means that contacts the transfer paper such as a transfer roller and a transfer belt may be used. good.

The cleaning means (8) includes a cleaning blade (80) made of a material such as rubber that contacts the photosensitive drum (1) and scrapes off residual toner, and a toner recovery chamber (81). Below the toner recovery chamber (81), a first toner conveying coil (82), which is a screw-type rotating body rotatably supported on the front and rear side plates of the cleaning means (8), is provided.
Further, a toner transport section (7) for transporting toner is provided so that the toner collected in the toner collection chamber (81) can be returned to the developing means (4) for recycling. A second toner transport coil (71) having the same shape as the first toner transport coil (82) is provided in the toner transport section (7).

The developing means (4) includes a developing tank (4a), which is a developing tank having stirring screws (41), (42) and a developing roller (40), and a toner cartridge for supplying toner to the developing tank (4a). 43) and a recycled toner hopper (4c). The developer used in the developing means (4) may be either a one-component developer or a two-component developer. A first supply roller (44) for supplying toner to the developing tank (4a) is provided at the bottom of the toner replenishing section (4b), and toner is supplied to the developing tank (4a) at the bottom of the recycled toner hopper (4c). A second supply roller (45), which is a collected toner supply roller for supply, and a mesh (46) on the developing tank (4a) side are provided in contact with the second supply roller (45).
As described above, the cleaning unit (8), the toner transport unit (7), the recycled toner hopper (4c), the second supply roller (45), and the mesh (46) constitute a toner recycling mechanism, and the cleaning unit (8 ) Can be recycled.
In the above configuration, the photosensitive drum (1) rotates clockwise, and an electrostatic latent image is formed on the surface of the photosensitive drum (1) by the charging and exposure operations by the main charger (2), and the developing means (4). The toner is supplied by the developing roller (40) and adheres to the electrostatic latent image to form a toner image. Next, after the toner image on the photosensitive drum (1) is transferred onto the transfer paper by the transfer charger (5a) and the separation charger (5b), the toner image is fixed by a fixing unit (not shown) and discharged.

  On the other hand, the toner remaining on the photosensitive drum (1) after the transfer is cleaned by the cleaning blade (80), and the photosensitive drum (1) is prepared for the next image formation. The toner scraped off by the cleaning blade (80) is collected in the toner collection chamber (81) and conveyed from the back side to the front side in the drawing by the rotation of the first toner transfer coil (82). Then, the toner is transported to the recycled toner hopper (4c) of the developing means (4) by the rotation of the second toner transport coil (71) of the toner transport section (7) and falls to the bottom thereof. The recycled toner is returned again to the developing tank (4a) by the second supply roller (45). At this time, the aggregated toner is finely crushed and supplied by passing through the mesh (46).

According to the image forming method of the present invention, the toner (hereinafter referred to as “initial toner”) contained in the initial developer first used in the developing means (4) and the toner in the developing tank (4a) are reduced. The refill toner supplied from the toner cartridge (43) has different characteristics. That is, the initial toner and the replenishment toner are toners having at least different particle diameters, and the replenishment toner has a larger weight average particle diameter than the initial toner.
In order to develop the electrostatic latent image on the photosensitive drum (1) precisely, the toner should have a small particle diameter and a spherical shape. However, as shown in FIG. 1, when the cleaning process is performed by the cleaning blade (80), the small particle size toner has a blade edge due to frictional resistance between the cleaning blade (80) and the surface of the photosensitive drum (1). Since the deformed cleaning blade (80) easily enters the space between the photosensitive drum (1) and the spherical toner easily rolls due to frictional force with the photosensitive drum (1), the cleaning blade (80). There is a problem in that sufficient cleaning performance cannot be obtained.
Therefore, according to the configuration of the present invention, according to the image forming operation, the initial toner of the developing means (4) reaches the edge of the cleaning blade (80) before the replenishing toner having a large weight average particle diameter. Is. The initial toner that has reached the edge of the cleaning blade (80) enters the space between the cleaning blade (80) and the photosensitive drum (1), and the tip of the blade and the photosensitive drum (1) by the toner having a small particle size. ) To prevent the subsequent toner from coming off. As a result, the developer tank (4a) is replenished as needed and developed on the photosensitive drum (1), and is carried to the cleaning blade (80) as the photosensitive drum (1) rotates. At this time, since a toner layer is formed between the blade tip and the photosensitive drum (1), the toner that has not been transferred in the transfer process is a large-diameter replenishment toner, so that it passes through the cleaning blade (80). Can be prevented.
The weight average particle diameter of the toner particles of the initial toner is preferably in the range of 4.0 to 7.0 μm. If the weight average particle size is less than 4.0 μm, some may slip through the cleaning blade (80), and cannot sufficiently fulfill the role of blocking the subsequent replenishing toner. On the other hand, if the weight average particle diameter exceeds 7.0 μm, the toner layer cannot be formed without gaps, and it becomes difficult to sufficiently fulfill the role of blocking the subsequent replenishing toner.

Measuring method of toner particle size distribution and average particle size:
Measuring machine: Coulter Multisizer II (Beckman Coulter, Inc.)
Aperture diameter: 100 μm
Electrolyte: Isoton II (Beckman Coulter, Inc.)
Dispersion: Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether HLB 13.6) 5% electrolyte
Dispersion condition: 5 ml of the dispersion is put into a 100 ml beaker, and 10 mg of a measurement sample is added to the dispersion. And it disperse | distributes for 1 minute with an ultrasonic disperser, Then, 25 ml of electrolyte solution is added, and it disperses for another 1 minute with an ultrasonic disperser.
Measurement conditions: 70 ml of electrolyte solution is put into a 100 ml beaker. Then, a liquid in which the sample is dispersed is added. As a concentration condition for adding the dispersion liquid, an amount of the dispersion liquid that can measure 30,000 particles in 20 seconds is added. The particle size of the particles is measured for 20 seconds to determine the particle size distribution. From the obtained distribution, the weight average particle diameter (D4) and the number average particle diameter of the toner can be obtained.

  As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm.

The toner particles of the initial toner are in the above weight average particle size range, and in order to increase the margin of the cleaning performance of the cleaning blade (80), the shape of the initial toner is an irregular toner having an average circularity of 0.93 or less. Is more preferable. This is because the irregular toner is more easily caught on the edge of the cleaning blade (80), and the subsequent spherical replenishing toner can be reliably blocked by the cleaning blade (80).
For the circularity of the toner particles, the value obtained from the following formula (1) is defined as the circularity. The circularity is an index of the degree of unevenness of the toner particles, and indicates 1.00 when the toner particles are perfectly spherical. The more complicated the surface shape, the smaller the circularity.

平均円形度が０．９３〜１．００の範囲では、トナー粒子の表面は滑らかであり、トナー粒子同士、トナー粒子と感光体との接触面積が小さいために転写性に優れる。
トナー粒子に角がないため、現像手段内での現像剤の攪拌トルクが小さく、攪拌の駆動が安定するために異常画像が発生しない。
ドットを形成するトナーの中に、角張ったトナー粒子がいないため、転写で転写媒体に圧接する際に、その圧がドットを形成するトナー全体に均一にかかり、転写中抜けが生じにくい。
トナー粒子が角張っていないことから、トナー粒子そのものの研磨力が小さく、感光体、帯電部材等の表面を傷つけたり、磨耗させたりしない。

When the average circularity is in the range of 0.93 to 1.00, the surface of the toner particles is smooth, and the contact area between the toner particles and between the toner particles and the photosensitive member is small, so that the transferability is excellent.
Since the toner particles have no corners, the developer agitation torque in the developing means is small, and the agitation drive is stabilized, so that no abnormal image is generated.
Since there are no angular toner particles in the toner forming dots, the pressure is uniformly applied to the entire toner forming dots when transferring and contacting the transfer medium, and transfer deficiency is unlikely to occur.
Since the toner particles are not angular, the abrasive power of the toner particles themselves is small, and the surfaces of the photoreceptor, the charging member and the like are not damaged or worn.

Next, a method for measuring the circularity will be described.
The circularity can be measured using a flow type particle image analyzer FPIA-1000 manufactured by Toa Medical Electronics.
As a specific measuring method, 0.3 ml of a surfactant, preferably alkylbenzene sulfonate, is added as a dispersant to 120 ml of water from which impure solids have been removed in advance, and about 0.3 g of a measurement sample is further added. Add. The suspension in which the sample is dispersed is subjected to dispersion treatment with an ultrasonic disperser for about 3 minutes, and the shape of the toner particles is measured by the above apparatus with the concentration of the dispersion being 3000 to 10000 / μl.

Measuring method of carrier particle size:
The weight average particle diameter (Dw) based on the particle size distribution of the relationship between the particle number frequency and the particle diameter measured on the basis of the number is calculated. The weight average particle diameter (Dw) is obtained from the following formula (B).

・Ｄは各チャンネルに存在する粒子の代表粒径（μｍ）
・ｎは各チャンネルに存在する粒子の総数
・チャンネルは粒径分布図における粒径範囲を等分に分割するための長さを表している。
粒径分布を測定する粒度分析計はマイクロトラック粒度分析計・モデルHRA 9320-X100（Honewell社製）を用いる。
・粒径範囲は：８〜１００μｍ
・チャンネル長さ（幅）：２μｍ
・屈折率：２．４２

-D is the representative particle size (μm) of the particles present in each channel
N is the total number of particles present in each channel. The channel represents a length for equally dividing the particle size range in the particle size distribution diagram.
As a particle size analyzer for measuring the particle size distribution, a Microtrac particle size analyzer / model HRA 9320-X100 (manufactured by Honewell) is used.
-Particle size range: 8-100 μm
・ Channel length (width): 2μm
-Refractive index: 2.42

Method for measuring charge quantity Q / M:
The measurement is performed by the blow-off method. The outline is that a two-component developer consisting of a toner and a carrier is put in a cage made of a metal cylinder with a metal mesh on both sides of the cylinder, and the metal cylinder cage is set horizontally in a Faraday gauge. The compressed gas is blown from the other end or both ends of the metal cylindrical cage to separate the toner and the carrier. The mesh size of the mesh is selected so that the toner passes and the carrier cannot pass. The charged toner passes through the mesh of the metal mesh and is blown out of the cage, but the carrier remains in the cage. The carrier in the cage retains the charge Q of the opposite polarity in the same amount as the charged toner is carried away, and charges the capacitor of the capacitance C connected to the cage. The voltage V across the capacitor is measured, and the specific charge amount (charge amount) of the toner is obtained from the following formula (C).

・現像剤量（Ｍ）を用いて、単位質量当たりのトナーの比電荷量（帯電量）はＱ／Ｍで表す。
・ファラデーケージの構成：２成分現像剤が入った金属製円筒からなるケージは接地した別の金属製円筒で完全に絶縁した構成になっている。
測定は東芝ケミカル（株）製のＴＢ−２００モデルを使用して測定する。
具体的には５００メシュの金網（キャリア粒子が通過しない大きさに適宜変更することができる）を使用して測定する。測定条件は次のようである。
ブローガス：窒素
ブロー圧力：１ｋｇ／ｃｍ^２
ブロー時間：４０秒
測定現像剤量：０．３ｇ

Using the developer amount (M), the specific charge amount (charge amount) of the toner per unit mass is represented by Q / M.
Faraday cage configuration: A cage made of a metal cylinder containing a two-component developer is completely insulated by another metal cylinder grounded.
The measurement is performed using a TB-200 model manufactured by Toshiba Chemical Corporation.
Specifically, the measurement is performed using a 500 mesh wire mesh (can be appropriately changed to a size that does not allow carrier particles to pass through). The measurement conditions are as follows.
Blow gas: Nitrogen Blow pressure: 1 kg / cm ²
Blow time: 40 seconds Measured developer amount: 0.3 g

By providing a toner recycling mechanism as in the image forming apparatus shown in FIG. 1, the initial toner recovered in the toner recovery chamber (81) is supplied again to the developing means (4), and again through the development process and transfer process. It can be used for a cleaning process. As a result, the initial toner is also recycled and can be included in the toner existing on the photosensitive drum (1) at a certain ratio.
In order to make the ratio of the initial toner contained in the toner present on the photosensitive drum (1) constant, the initial toner preferably has the following configuration.
Although it has been described that the initial toner is preferably an amorphous toner having an average circularity of 0.93 or less from the viewpoint of blade cleaning performance, it can be said that it is also preferable from the viewpoint of recycling of the initial toner. This is because the irregular toner is more difficult to transfer to the surface of the photosensitive drum (1) than the toner having a nearly spherical shape, so that it remains on the photosensitive drum (1) even after the transfer process. This is because the cleaning process is reached. The irregular toner enters the space between the photosensitive drum (1) and the cleaning blade (80) again, and a toner layer is formed between the blade tip and the photosensitive drum (1), so it is not transferred in the transfer process. Since the toner is a replenishing toner having a large particle diameter, it is possible to prevent the cleaning blade (80) from slipping through.
Similarly, from the viewpoint of initial toner recycling, it is preferable that the initial toner has a shorter relaxation time of the toner surface potential after being frictionally charged by the developing means (4). If the toner surface potential relaxation time is short, the amount of toner charge is attenuated in the process of developing on the photosensitive drum (1) and then the transfer process, so that it is difficult to transfer, and therefore remains on the photosensitive drum (1). To do.
Examples of such a toner include those containing any one of an azo metal complex compound, a quaternary ammonium salt, a fluorine-containing quaternary ammonium salt, and a salicylic acid metal complex compound as a charge control agent on the toner surface.

  In addition, in order to reduce the volume specific resistance of the toner, conductive fine particles can be externally added so as to accelerate the decay of the surface potential caused by frictional charging of the initial toner. Examples of the conductive fine particles include low resistance materials such as titanium oxide, antimony oxide, tin oxide, aluminum oxide, iron oxide, and zinc oxide, or high dielectric materials such as Rochelle salts (Rochelle salt, Potassium sodium tartrate, lithium ammonium tartrate, etc.), perovskite type (barium titanate, strontium titanate, lead titanate, sodium tantalate, lead zirconate titanate, etc.), picrolite type (cadmium niobate, lead pyroniobate, etc.) ), Ilmenite type (cadmium titanate, iron titanate, nickel titanate, lithium titanate, etc.), guanazine type (guanazine gallium sulfate, guanazine chromium sulfate, etc.), glycine type (sulfuric acid) Glycine, silver glycine sulfate, etc.), solid solution ( Lead titanate / lead zirconate, niobic acid / barium niobate, etc.), cyanoresins, copolymers (polyvinylidene fluoride-trifluoroethylene, polyvinylidene fluoride-tetrafluoroethylene, etc.) can be used. .

Furthermore, the initial toner is preferably a toner containing a release agent. In order to prevent hot offset in the fixing unit, a method of adding a release agent to the toner is well known. When the toner added with the release agent is used as the initial toner, the initial toner stays in the space between the photosensitive drum (1) and the cleaning blade (80) for a long time, so that the added release agent is exposed on the surface of the toner particles. If this occurs, filming is likely to occur on the photosensitive drum (1). Therefore, it is preferable to use the toner containing the release agent as the initial toner.
As a method for encapsulating the release agent in the toner, the surface layer portion containing the release agent inside using a toner production method such as suspension polymerization, emulsion polymerization, precipitation polymerization, dispersion polymerization, soap-free emulsion polymerization and seed polymerization. And a method of forming a so-called capsule-like toner in which is formed of a polymer. For example, in the case of using the suspension polymerization method, a toner monomer solution and a colorant as well as a polymerization initiator, a crosslinking agent, a release agent, and the like, which are toner materials, are uniformly dissolved and dispersed. After that, the toner material liquid is dispersed in an aqueous phase containing a dispersion stabilizer using a stirrer, and polymerization is performed at the same time.

Next, a replenishing toner that is preferably used in the present image forming method will be described.
The toner particles of the replenishing toner have a weight average particle diameter of 5.0 to 9.5 μm and a ratio (D4 / Dn) of the weight average particle diameter (D4) to the number average particle diameter (Dn) of 1.00 to 1.00. It is preferable to be in the range of 1.40. By using a toner having such a particle size and particle size distribution, it is excellent in heat-resistant storage stability, low-temperature fixability, and hot offset resistance, and particularly when used in a full-color copying machine, etc. Sex is obtained.
In general, the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning properties. The image forming method of the present invention leaves problems for high-resolution and high-quality images, but is packed in the blade tip using toner having a weight average particle size smaller than that of the replenishment toner as the initial toner. With respect to the toner, there is no slipping of the toner, and it is possible to exhibit a good blade cleaning performance that is stable and reliable over a long period of time. On the other hand, if Dv / Dn exceeds 1.40, the charge amount distribution becomes wide and the resolving power decreases, which is not preferable.
The average circularity of the toner particles of the replenishing toner is preferably 0.94 or more. By using a toner having an average circularity of 0.94 or more, dot reproducibility is excellent and a high transfer rate can be obtained. When the average circularity is less than 0.94, the toner is separated from the spherical shape, the dot reproducibility is deteriorated, and the number of contact points with the photosensitive drum (1) as the latent image carrier increases, so that the separation is increased. The moldability deteriorates and the transfer rate decreases.
As described above, even when a toner having a toner particle having a high average circularity and a nearly spherical shape is used, a good blade cleaning performance can be exhibited by the image forming method of the present invention.

The toner particles of the replenishing toner are preferably toners that can be defined by the values of the following shape factors SF-1 and SF-2. FIG. 2 is a diagram schematically showing the shape of the toner in order to explain the shape factor SF-1 and the shape factor SF-2.
The shape factor SF-1 represents the ratio of the roundness of the toner shape and is represented by the following formula (2). This is a value obtained by dividing the square of the maximum length MXLNG of the shape formed by projecting the toner on a two-dimensional plane by the figure area AREA and multiplying by 100π / 4.

ＳＦ−１の値が１００の場合トナー粒子の形状は真球となり、ＳＦ−１の値が大きくなるほど不定形になる。

When the value of SF-1 is 100, the shape of the toner particles is a true sphere, and becomes irregular as the value of SF-1 increases.

  The shape factor SF-2 indicates the ratio of the unevenness of the shape of the toner particles, and is represented by the following formula (3). A value obtained by dividing the square of the perimeter PERI of the figure formed by projecting the toner on the two-dimensional plane by the figure area AREA and multiplying by 100π / 4.

ＳＦ−２の値が１００の場合トナー表面に凹凸が存在しなくなり、ＳＦ−２の値が大きくなるほどトナー表面の凹凸が顕著になる。
形状係数の測定は、具体的には、走査型電子顕微鏡（Ｓ−８００：日立製作所製）でトナーの写真を撮り、これを画像解析装置（ＬＵＳＥＸ３：ニレコ社製）に導入して解析して計算した。

When the value of SF-2 is 100, there is no unevenness on the toner surface, and as the value of SF-2 increases, the unevenness of the toner surface becomes more prominent.
Specifically, the shape factor is measured by taking a photograph of the toner with a scanning electron microscope (S-800: manufactured by Hitachi, Ltd.), introducing it into an image analyzer (LUSEX 3: manufactured by Nireco) and analyzing it. Calculated.

The toner according to the present invention is a toner having SF-1 in the range of 100 to 180 and SF-2 in the range of 100 to 180. When the shape of the toner is close to a spherical shape, the contact between the toner and the toner or the toner and the photosensitive drum (1) becomes a point contact, so that the adsorbing force between the toners becomes weak and the fluidity becomes high. And the photosensitive drum (1) are also weakened, and the transfer rate is increased. Even when such a nearly spherical toner is used as the replenishing toner, good blade cleaning performance can be obtained by the image forming method of the present invention.
On the other hand, when the toner shape factors SF-1 and SF-2 are large to some extent, the cleaning margin increases. However, if the toner shape factors SF-1 and SF-2 are too large, the toner is scattered on the image and the image quality is lowered. For this reason, it is preferable that SF-1 and SF-2 do not exceed 180.

The toner for the initial agent and the toner for replenishment can be prepared by a known toner constituent material and manufacturing method.
The colorant used in the present invention can also be used as a master batch combined with a resin. As the binder resin to be kneaded together with the production of the master batch or the master batch, in addition to the above-mentioned modified and unmodified polyester resins, styrene such as polystyrene, poly p-chlorostyrene, and polyvinyl toluene, and polymers of substituted products thereof; Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α- Chloromethyl methacrylate copolymer, Tylene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid Styrene copolymers such as acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, poly Acrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. The

The master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force to obtain a master batch. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. Also, a so-called flushing method called watering paste containing water of a colorant is mixed and kneaded together with a resin and an organic solvent, and the colorant is transferred to the resin side to remove moisture and organic solvent components. Since it can be used as it is, it does not need to be dried and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used. As a method for producing the toner used in the present invention, it can be produced by various known methods or a combination thereof. For example, in the kneading and pulverization method, necessary materials such as a binder resin and a colorant are dry-mixed, heated and kneaded with an extruder, two rolls, three rolls, etc., and then cooled and solidified. In this case, the particles are collided and pulverized by airflow disturbance in the supersonic nozzle that generates an airflow, and the solid / gas mixture is collided with a collision plate (ceramic) installed in front of the nozzle. Specifically, it is pulverized by a supersonic jet mill pulverizer (I type, I2 type mill, etc.). If necessary, the toner is classified by a classifier.
Such a toner has an irregular shape with corners. Therefore, by applying hot air or mechanical energy to the pulverized / classified toner, the surface of the toner may be rounded, and processing may be performed so as to approach the spherical toner as much as possible from the irregular shape. In such a shape, the fluidity of the toner particles is improved. The following method is mentioned as the specific method.

[Mechanical processing]
For example, as described in JP 09-087441 A, a method using a turbo mill (manufactured by Turbo Industry), a kryptron (manufactured by Kawasaki Heavy Industries), a Q-type mixer (manufactured by Mitsui Mine), a hybridizer (Nara Machinery) ) And mechano-fusion device (made by Hosokawa Micron etc.), the shape of the pulverized toner can be made spherical.

[Heat treatment (dry type)]
For example, the shape of the pulverized toner can be made spherical by semi-melting the surface of the toner particles with hot air of 100 to 300 ° C. using a surffusion system (Nippon Pneumatic Industry).

[Heat treatment (wet)]
By immersing the toner obtained by the pulverization method in a high-temperature liquid at a temperature at which the toner has plasticity (about 200 ° C.), the shape of the toner particles of the pulverized toner can be made spherical.
In addition, toner particles that are almost as spherical as the toner obtained by the polymerization method can be obtained. For example, the toner may be prepared by suspension polymerization, emulsion polymerization, dispersion polymerization, interfacial polymerization, phase inversion emulsification by chemical treatment, dissolution suspension, polyester elongation reaction, or the like.
A toner obtained by a polyester elongation reaction is obtained by dropping a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent is dispersed in an organic solvent in an aqueous solvent. The toner is obtained by dispersing and emulsifying in the form of cross-linking and / or elongation reaction. The constituent material and manufacturing method of the toner will be described. This material can also be used in the grinding method if necessary.

(Modified polyester)
The toner according to the present invention contains a modified polyester (i) as a binder resin. The modified polyester (i) refers to a state in which a bonding group other than an ester bond is present in the polyester resin, or resin components having different configurations are bonded to the polyester resin by a covalent bond, an ionic bond, or the like. Specifically, the polyester terminal is modified by introducing a functional group such as a carboxylic acid group or an isocyanate group that reacts with a hydroxyl group into the polyester terminal and further reacting with an active hydrogen-containing compound.

  Examples of the modified polyester (i) include urea-modified polyester obtained by a reaction between a polyester prepolymer (A) having an isocyanate group and amines (B). As the polyester prepolymer (A) having an isocyanate group, a polycondensate of a polyhydric alcohol (PO) and a polyvalent carboxylic acid (PC) and a polyester having an active hydrogen group, a polyvalent isocyanate compound (PIC) And those reacted with. Examples of the active hydrogen group possessed by the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable.

The urea-modified polyester is produced as follows.
Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable. Examples of the dihydric alcohol (DIO) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. The trihydric or higher polyhydric alcohol (TO) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

  Examples of the polyvalent carboxylic acid (PC) include divalent carboxylic acid (DIC) and trivalent or higher polyvalent carboxylic acid (TC). (DIC) alone and (DIC) with a small amount of (TC) Mixtures are preferred. Divalent carboxylic acids (DIC) include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polyvalent carboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polyhydric carboxylic acid (PC), you may make it react with polyhydric alcohol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

  The ratio of the polyhydric alcohol (PO) to the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Is 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.) Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; Those blocked with caprolactam or the like; and combinations of two or more of these.

  The ratio of the polyvalent isocyanate compound (PIC) is usually 5/1 to 1/1, preferably as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. When the molar ratio of [NCO] is less than 1, when a urea-modified polyester is used, the urea content in the ester is lowered and hot offset resistance is deteriorated.

The content of the polyvalent isocyanate compound (PIC) component in the polyester prepolymer (A) having an isocyanate group is usually 0.5 to 40 wt%, preferably 1 to 30 wt%, more preferably 2 to 20 wt%. . If it is less than 0.5 wt%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40 wt%, the low-temperature fixability deteriorates.
The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. If it is less than 1 per molecule, the molecular weight of the urea-modified polyester will be low, and the hot offset resistance will deteriorate.

Next, as amines (B) to be reacted with the polyester prepolymer (A), a divalent amine compound (B1), a trivalent or higher polyvalent amine compound (B2), an amino alcohol (B3), an amino mercaptan (B4) ), Amino acid (B5), and amino acid block of (B1) to (B5) (B6).
Examples of the divalent amine compound (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexyl). Methane, diamine cyclohexane, isophorone diamine, etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine, etc.) and the like. Examples of the trivalent or higher polyvalent amine compound (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of the blocked B1-B5 amino group (B6) include ketimine compounds and oxazolidine compounds obtained from the amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) of (B1) to (B5). Can be mentioned. Among these amines (B), preferred are (B1) and a mixture of (B1) and a small amount of (B2).
The ratio of amines (B) is equivalent to the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the polyester prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). Is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] is more than 2 or less than 1/2, the molecular weight of the urea-modified polyester is lowered, and the hot offset resistance is deteriorated.

  The urea-modified polyester may contain a urethane bond together with a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

The modified polyester (i) used in the present invention is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the modified polyester (i) is usually 10,000 or more, preferably 20,000 to 10,000,000, more preferably 30,000 to 1,000,000. The peak molecular weight at this time is preferably 1000 to 10000. When the molecular weight is less than 1000, the elongation reaction hardly occurs, the elasticity of the toner is small, and as a result, the resistance to hot offset deteriorates. On the other hand, when it exceeds 10,000, the problem in production becomes high in the deterioration of fixability, particle formation and pulverization. The number average molecular weight of the modified polyester (i) is not particularly limited when the unmodified polyester (ii) described later is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. (I) When used alone, the number average molecular weight is usually 20000 or less, preferably 1000 to 10000, and more preferably 2000 to 8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color device are deteriorated.
In the crosslinking and / or extension reaction between the polyester prepolymer (A) and the amines (B) to obtain the modified polyester (i), a reaction terminator is used as necessary to adjust the molecular weight of the resulting urea-modified polyester. be able to. Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).
In addition, the molecular weight of the produced | generated polymer can be measured using a gel permeation chromatography (GPC).

(Unmodified polyester)
In the present invention, not only the modified polyester (i) is used alone, but also the unmodified polyester (ii) can be contained as a binder resin component together with the (i). By using (ii) in combination, the low-temperature fixability and the gloss when used in a full-color device are improved, which is preferable to single use. Examples of (ii) include polycondensates of polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) similar to the polyester component of (i), and preferred ones are also the same as (i). . (Ii) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, and may be modified with a urethane bond, for example. It is preferable that (i) and (ii) are at least partially compatible in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component (i) and (ii) preferably have similar compositions. When (ii) is contained, the weight ratio of (i) to (ii) is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, Particularly preferred is 7/93 to 20/80. When the weight ratio of (i) is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.
The peak molecular weight of (ii) is usually 1000 to 10,000, preferably 2000 to 8000, and more preferably 2000 to 5000. If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 10,000, low-temperature fixability will deteriorate. The hydroxyl value of (ii) is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. The acid value of (ii) is preferably 1 to 5, more preferably 2 to 4. Since a high acid value wax is used as the wax, the low acid value binder leads to electrification and high volume resistance, so that it is easy to match the toner used for the two-component developer.

The glass transition point (Tg) of the binder resin is usually 35 to 70 ° C, preferably 55 to 65 ° C. If the temperature is lower than 35 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Since the urea-modified polyester is likely to be present on the surface of the obtained toner base particles, the toner of the present invention tends to have good heat storage stability even when the glass transition point is low, as compared with known polyester-based toners. Show.
The glass transition point (Tg) can be measured with a differential scanning calorimeter.

(Coloring agent)
As the colorant, known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, Yellow lead, Titanium yellow, Polyazo yellow, Oil yellow, Hansa yellow (GR, A, RN, R), Pigment yellow L, Benzidine yellow (G, GR), Permanent yellow (NCG), Vulcan fast yellow (5G, R) ), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Se Red, parachlor ortho nitroa Lynn Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carnmin BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R , Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thio Indigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red, Po Azo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), indigo, ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalo Anine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant can also be used as a master batch combined with a resin. As a binder resin to be kneaded with the production of the master batch or the master batch, a polymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyl toluene or the like, or a copolymer of these and a vinyl compound, Polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, fat Aromatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be mentioned, and these can be used alone or in combination.

(Charge control agent)
Known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified 4 Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenolic condensate E-89 (above, Orient Chemical Industries, Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy Charge PSY VP2038, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit) Manufactured), copper phthalocyanine, perylene, quinacridone, azo series Fee, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as quaternary ammonium salts. Of these, substances that control the negative polarity of the toner are particularly preferably used.
The amount of charge control agent used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is not uniquely limited. Preferably, it is used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the charge control agent is reduced, the electrostatic attraction with the developing roller is increased, the flowability of the developer is lowered, and the image density is lowered. Invite.

(Release agent)
As a release agent, a low melting point wax having a melting point of 50 to 120 ° C. works more effectively as a release agent in the dispersion with the binder resin between the fixing roller and the toner interface. The effect on high temperature offset is exhibited without applying a release agent such as oil. Examples of such a wax component include the following. Examples of waxes and waxes include plant waxes such as carnauba wax, cotton wax, wood wax, and rice wax, animal waxes such as beeswax and lanolin, mineral waxes such as ozokerite and cercin, and paraffin, microcrystalline, And petroleum waxes such as petrolatum. In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax, and synthetic waxes such as esters, ketones, and ethers can be used. Furthermore, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, chlorinated hydrocarbon, and low molecular weight crystalline polymer resin, poly-n-stearyl methacrylate, poly-n- A crystalline polymer having a long alkyl group in the side chain such as a homopolymer or copolymer of polyacrylate such as lauryl methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.) can also be used. .
The charge control agent and the release agent can be melt-kneaded together with the master batch and the binder resin, and of course, they may be added when dissolved and dispersed in the organic solvent.

(External additive)
Inorganic fine particles are preferably used as an external additive for assisting the fluidity, developability and chargeability of the toner particles. The primary particle diameter of the inorganic fine particles is preferably 5 × ¹⁰ -3 ~2μm, it is particularly preferably 5 × ¹⁰ -3 ~0.5μm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The use ratio of the inorganic fine particles is preferably 0.01 to 5 wt% of the toner, and particularly preferably 0.01 to 2.0 wt%.
Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Among these, as the fluidity imparting agent, it is preferable to use hydrophobic silica fine particles and hydrophobic titanium oxide fine particles in combination. In particular, when stirring and mixing are performed using particles having an average particle diameter of 5 × 10 ⁻² μm or less, the electrostatic force and van der Waals force with the toner are remarkably improved. Even with stirring and mixing inside the developing device (means) performed to obtain a good image quality that does not cause the release of fluidity from the toner and does not generate fireflies, etc. Reduction is achieved.
Titanium oxide fine particles are excellent in environmental stability and image density stability, but have a tendency to deteriorate the charge rise characteristics. Therefore, if the amount of titanium oxide fine particles added is larger than the amount of silica fine particles added, this side effect is affected. It can be considered large. However, when the added amount of the hydrophobic silica fine particles and the hydrophobic titanium oxide fine particles is in the range of 0.3 to 1.5 wt%, the charge rising characteristics are not greatly impaired, and the desired charge rising characteristics can be obtained, that is, repeated copying. Stable image quality can be obtained even if

Next, a toner manufacturing method will be described. Here, although a preferable manufacturing method is shown, it is not limited to this.
(Toner production method)
1) A toner material solution is prepared by dispersing a colorant, unmodified polyester, a polyester prepolymer having an isocyanate group, and a release agent in an organic solvent.
The organic solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal after toner base particle formation. Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, Methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. The usage-amount of an organic solvent is 0-300 weight part normally with respect to 100 weight part of polyester prepolymers, Preferably it is 0-100 weight part, More preferably, it is 25-70 weight part.

2) The toner material liquid is emulsified in an aqueous medium in the presence of a surfactant and resin fine particles.
The aqueous medium may be water alone or an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). It may be included.
The amount of the aqueous medium used relative to 100 parts by weight of the toner material liquid is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight. If the amount is less than 50 parts by weight, the dispersion state of the toner material liquid is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 2000 parts by weight, it is not economical.
Further, in order to improve the dispersion in the aqueous medium, a dispersant such as a surfactant and resin fine particles is appropriately added.
As surfactants, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, fatty acid amide derivative, polyhydric alcohol Nonionic surfactants such as derivatives, for example, amphoteric surfactants such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine And the like.
Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-Hydroxyethyl) Perful Olooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Can be mentioned.
Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Daikin Industries, Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (manufactured by Dainippon Ink, Inc.), Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).
Moreover, as the cationic surfactant, aliphatic quaternary ammonium such as aliphatic primary, secondary or secondary amic acid, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt which has a right fluoroalkyl group is used. Salt, benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (Asahi Glass Co., Ltd.), Florard FC-135 (Sumitomo 3M Co., Ltd.), Unidyne DS-202 (Daikin Industries) Smoke), Megafac F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products), Footage F-300 (Neos), and the like.
The resin fine particles are added to stabilize the toner base particles formed in the aqueous medium. For this reason, it is preferable to add so that the coverage existing on the surface of the toner base particles is in the range of 10 to 90%. For example, polymethyl methacrylate fine particles 1 μm and 3 μm, polystyrene fine particles 0.5 μm and 2 μm, poly (styrene-acrylonitrile) fine particles 1 μm, trade names are PB-200H (manufactured by Kao Corporation), SGP (manufactured by Soken Co., Ltd.), Techno Examples include polymer SB (manufactured by Sekisui Chemical Co., Ltd.), SGP-3G (manufactured by Sokensha), and micropearl (manufactured by Sekisui Fine Chemical Co., Ltd.).
In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.
As a dispersant that can be used in combination with the above resin fine particles and inorganic compound dispersant, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Bodies such as acrylic acid-β-hydroxyethyl, methacrylic acid-β-hydroxyethyl, acrylic acid-β-hydroxypropyl, methacrylic acid-β-hydroxypropyl, acrylic acid-γ-hydroxypropyl, methacrylic acid-γ-hydroxy Propyl, acrylic acid-3-chloro-2-hydroxypropyl, methacrylic acid-3-chloro-2-hydroxypropyl, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate Luric acid esters, N-methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or compounds containing vinyl alcohol and a carboxyl group Esters such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl Nitrogen compounds such as imidazole and ethyleneimine, or homopolymers or copolymers such as those having a heterocyclic ring thereof, polyoxyethylene, poly Xoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxy Polyoxyethylenes such as ethylene nonylphenyl ester, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.
The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. Among these, the high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the number of rotations is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.

3) At the same time as the preparation of the emulsion, the amines (B) are added to cause a reaction with the polyester prepolymer (A) having an isocyanate group.
This reaction involves molecular chain crosslinking and / or elongation. The reaction time is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

4) After completion of the reaction, the organic solvent is removed from the emulsified dispersion (reactant), washed and dried to obtain toner base particles.
In order to remove the organic solvent, the temperature of the entire system is gradually raised in a laminar stirring state, and after giving strong stirring in a certain temperature range, the solvent base is removed to produce spindle-shaped toner base particles. . When a dispersion stabilizer that is soluble in an acid or alkali such as calcium phosphate is used, the calcium phosphate is dissolved from the toner base particles by a method such as dissolving the calcium phosphate with an acid such as hydrochloric acid and washing with water. Remove. It can also be removed by operations such as enzymatic degradation.

5) A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are externally added to obtain a toner.
The injection of the charge control agent and the external addition of the inorganic fine particles are performed by a known method using a mixer or the like.
Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the true spherical shape and the rugby ball shape can be controlled, and the surface morphology is also controlled between the smooth shape and the umeboshi shape. be able to.

Further, the toner particles of the toner according to the present invention have a substantially spherical shape and can be represented by the following shape rule.
FIG. 3 is a diagram schematically showing the shape of the toner according to the present invention. In FIG. 3, when a substantially spherical toner is defined by a major axis r1, a minor axis r2, and a thickness r3 (where r1 ≧ r2 ≧ r3), the toner of the present invention has a major axis and a minor axis. Ratio (r2 / r1) (see FIG. 3B) is 0.5 to 1.0, and the ratio of thickness to minor axis (r3 / r2) (see FIG. 3C) is 0.7 to 1.0. It is preferable to be in the range of 1.0. When the ratio of the major axis to the minor axis (r2 / r1) is less than 0.5, the dot reproducibility and transfer efficiency are inferior because of being away from the true spherical shape, and high-quality image quality cannot be obtained. On the other hand, if the ratio of thickness to minor axis (r3 / r2) is less than 0.7, the shape is close to a flat shape, and a high transfer rate like a spherical toner cannot be obtained. In particular, when the ratio of the thickness to the minor axis (r3 / r2) is 1.0, the rotating body has a major axis as a rotation axis, and the fluidity of the toner can be improved.
Note that r1, r2, and r3 were measured with a scanning electron microscope (SEM) while changing the angle of field of view and taking pictures.
The toner produced as described above can also be used as a one-component magnetic toner that does not use a magnetic carrier or a non-magnetic toner.
When used in a two-component developer, it may be used by mixing with a magnetic carrier, and the magnetic carrier is a ferrite containing a divalent metal such as iron, magnetite, Mn, Zn, Cu, A weight average particle size of 20 to 100 μm is preferred. If the average particle size is less than 20 μm, carrier adhesion is likely to occur on the photoreceptor 1 during development, and if it exceeds 100 μm, the miscibility with the toner is low and the charge amount of the toner is insufficient, resulting in poor charging during continuous use. Cheap. In addition, Cu ferrite containing Zn is preferable because of high saturation magnetization, but can be appropriately selected according to the process of the image forming apparatus. The resin for coating the magnetic carrier is not particularly limited, and examples thereof include silicone resin, styrene-acrylic resin, fluorine-containing resin, and olefin resin. In the manufacturing method, the coating resin may be dissolved in a solvent, sprayed into a fluidized bed and coated on the core, or the resin particles are electrostatically attached to the core particles and then thermally melted for coating. It may be a thing. The resin to be coated has a thickness of 0.05 to 10 μm, preferably 0.3 to 4 μm.

  FIG. 4 is a schematic configuration diagram of an image forming apparatus according to the second embodiment of the present invention. Around the photosensitive drum (1) as an image carrier, a main charger (2) for charging the surface of the photosensitive drum (1), and black for developing an electrostatic latent image formed on the surface of the photosensitive drum (1). Developing means (4Bk), (4C), (4M), (4Y) corresponding to toners of four colors (Bk), cyan (C), magenta (M), and yellow (Y), photosensitive drum (1) A cleaning means (8) for cleaning the upper residual toner is disposed.

The surface of the photosensitive drum (1) is uniformly charged by the main charger (2), and exposure light based on image information of any of the four colors is irradiated from an exposure unit (not shown) to thereby form an electrostatic latent image. Is formed. Thereafter, toner is supplied by the corresponding color developing means (4), and a one-color toner image is formed on the photosensitive drum (1).
An intermediate transfer belt (50) for transferring and holding the toner image formed on the photosensitive drum (1) is disposed below the photosensitive drum (1). The intermediate transfer belt (50) is an endless belt that is stretched and supported by support rollers (51), (52), (53), (54), (55), and (56). A support roller (51) disposed opposite to and in pressure contact with the photosensitive drum (1) via the intermediate transfer belt (50) also serves as a primary transfer unit, and a primary transfer voltage is applied from a power source (not shown). One color toner image formed on the photosensitive drum (1) is transferred onto the intermediate transfer belt (50).

On the other hand, the surface of the photosensitive drum (1) after the toner image transfer is cleaned by a cleaning means (8) having a cleaning blade (80). Then, the surface is again uniformly charged by the main charger (2), and another color toner image is formed on the photosensitive drum (1) by the same process as before. The toner image formed on the photosensitive drum (1) is transferred onto the intermediate transfer belt (50) on which the first color toner image is carried. In this way, toner images are sequentially formed on the photosensitive drum (1) one by one, transferred onto the intermediate transfer belt (50) and superimposed, and finally the four color toner images are superimposed. A full color image is formed.
A secondary transfer belt (62) is disposed below the intermediate transfer belt (50). The secondary transfer belt (62) is an endless belt that is stretched and supported by support rollers (63), (64), and (65). During the primary transfer process, the secondary transfer belt (62) is separated from the intermediate transfer belt (50). When the primary transfer process is completed and a color image is formed on the intermediate transfer belt (50), the secondary transfer belt (62) is pressed against the portion of the intermediate transfer belt (50) supported by the support roller (55). To form a nip. The transfer paper is conveyed to the nip from a paper supply means (not shown), and a secondary transfer voltage is applied to the support roller (63) from a power supply (not shown), so that the color image on the intermediate transfer belt (50) is transferred to the transfer paper. Is done.
The transfer sheet on which the color image has been transferred is carried and conveyed by the secondary transfer belt (62), and the image is fixed by the fixing means (9).

On the other hand, the surface of the intermediate transfer belt (50) after the completion of the secondary transfer is cleaned by an intermediate transfer belt cleaning means (57) provided with a cleaning blade (58).
As in the first embodiment, the initial toner used first in the developing means (4Bk), (4C), (4M), and (4Y) and replenishment as needed according to the decrease in the toner in each developing means (4) The replenishment toner is a toner having at least a different particle diameter, and the replenishment toner has a larger weight average particle diameter than the initial toner. The details of the initial toner and the replenishing toner are the same as described above, and will be omitted.
In the second embodiment, the recovery tank (4d) and the toner conveying section (7) are obtained so that the toner recovered by the cleaning means (8) is returned to the developing means (4Bk) for recycling. May be. Also in the second embodiment, the initial toner used in each developing means 4 is recycled and supplied again onto the photosensitive drum (1), and a large-diameter replenishing toner is supplied to the cleaning blade (80). It may be configured to prevent slipping through and maintain good blade cleaning performance.
Further, although not shown in FIG. 4, there may be provided a toner conveying section for conveying the toner collected by the intermediate transfer belt cleaning means (57) provided in the intermediate transfer belt (50) to the collection tank (4d). . As a result, the initial toner remaining on the intermediate transfer belt (50) without being subjected to secondary transfer can be recycled.

FIG. 5 is a schematic configuration diagram of an image forming apparatus according to the third embodiment of the present invention.
An image provided with various means for executing an electrophotographic process such as a main charger (2) as a charging means, a developing means (4), and a cleaning means (8) around a photosensitive drum (1) as a latent image carrier. Four forming means are arranged in parallel corresponding to four colors of black (Bk), yellow (Y), magenta (M), and cyan (C). Above the image forming means, there is provided an exposure means (not shown) for exposing the photosensitive drum (1) with exposure light based on image information to form an electrostatic latent image. In each image forming unit, an electrostatic latent image is formed on each photosensitive drum (1) based on the image information of each color, and the electrostatic latent image is developed with each color toner by the developing unit (4). It is formed.
An intermediate transfer belt made of an endless belt member stretched and supported by support rollers (52), (53), (54) is located at a position facing each photosensitive drum (1) of each image forming unit. 50). Primary transfer for transferring the toner images of the respective colors formed on the respective photosensitive drums (1) to the intermediate transfer belt (50) at positions facing the photosensitive drum (1) via the intermediate transfer belt (50). Each means (51) is arranged. The intermediate transfer belt (50) is rotationally driven in the direction of the arrow in the figure, and the toner images on the photosensitive drums (1) are sequentially transferred onto the intermediate transfer belt (50) as the belt moves. On the intermediate transfer belt 50 that has passed the photosensitive drum black (Bk), yellow (Y), magenta (M), and cyan (C), a color image in which four color toner images are overlapped is formed.
A secondary transfer roller (61) is provided in pressure contact with the portion of the intermediate transfer belt (50) supported by the support roller (53). When the color image on the intermediate transfer belt (50) reaches the nip between the intermediate transfer belt (50) and the secondary transfer roller (61), a secondary transfer voltage is applied to the secondary transfer roller (61) from a power source (not shown). Then, the sheet is transferred onto a transfer sheet conveyed to the nip portion from a sheet feeding means (not shown).
The transfer sheet on which the color image has been transferred is carried and conveyed by the conveyance belt (66), and the color image is fixed on the sheet by the fixing means (9).

On the other hand, the surfaces of the respective photosensitive drums (1) after the primary transfer and the intermediate transfer belt (50) after the secondary transfer are provided with cleaning means (8) or cleaning blades (58) each having a cleaning blade (80). Cleaning is performed by the intermediate transfer belt cleaning means (57) provided.
Also in the third embodiment, as in the first embodiment, the initial toner used first in the developing means (4Bk), (4Y), (4M), and (4C) and the inside of each developing means (4) The replenishment toner that is replenished as needed according to the decrease in the toner is a toner that has at least a different particle diameter, and the replenishment toner has a larger weight average particle diameter than the initial toner. The details of the initial toner and the replenishing toner are the same as described above, and will be omitted.
Although not shown in FIG. 5, a toner transport unit is provided for returning the toner collected by each cleaning means (8) to each developing means (4) in the same image forming means. You may make it the structure recycled. A toner recycling mechanism similar to that of the first embodiment can be used. In this way, also in the third embodiment, the initial toner used in each developing means (4) is recycled and supplied again to each photosensitive drum (1), so that a large-diameter replenishment toner is supplied. It is possible to prevent the cleaning blade (80) from slipping through and maintain good blade cleaning performance.
Although not shown in FIG. 5, there may be provided a toner conveying section for conveying the toner collected by the intermediate transfer belt cleaning means (57) provided in the intermediate transfer belt (50) to the developing means (4Bk). good. As a result, the initial toner remaining on the intermediate transfer belt (50) without being subjected to secondary transfer can be recycled.

  The present invention includes a photosensitive drum (1) and a developing unit (4) in the image forming apparatus shown in the first and third embodiments, and is supported integrally and detachable from the main body of the image forming apparatus. The present invention can also be applied to a process cartridge formed in the above. The process cartridge may further include a charging unit and a cleaning unit. The initial toner of the developing means (4) and the replenishing toner are toners having at least different particle diameters, and the same effect can be obtained by making the replenishing toner a toner having a larger weight average particle diameter than the initial toner. Obtainable.

Hereinafter, the present invention will be described more specifically with reference to examples.
Example 1
1) Black toner example A1 for initial developer
・ Binder resin: 100 parts of polyester resin (Propylene oxide adduct of bisphenol A, polyester synthesized from terephthalic acid and succinic acid derivative)
Charge control agent: zinc salicylate (Bontron E84, Orient Chemical) 2 parts Release agent: 3.5 parts carnauba wax Coloring agent: carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7.5 parts After preliminarily kneading the prescribed amount with a mixer, melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, the toner was classified to obtain a toner having a weight average particle diameter of 4.0 μm. The average circularity of the toner particles was 0.88.
An initial developer is prepared by mixing 1.1 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.5 part of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with 100 parts by weight of the toner. A black toner A1 was prepared.

2) Example of magnetic carrier Z1
A coating solution was prepared according to the following formulation.
-Silicon resin SR2411 (solid content 20%, manufactured by Tore Dow Corning) 450 parts-Toluene 1200 parts The above liquid was placed in a rotating disk type fluidized bed coating apparatus together with 5 kg of ferrite carrier having an average particle size of 35 µm to coat the carrier. Thereafter, the film was aged by heating at 250 ° C. for 2 hours to obtain a magnetic carrier.
Place 926 g of magnetic carrier Z1 and 74 g of black toner A1 in a 1 L container so that the total amount of toner and carrier obtained above is 1000 g, respectively, and add a tumbler shaker mixer T2F type (Shinmaru Enterprise Co., Ltd.) The initial developer having a toner concentration of 7.4% was prepared by mixing for 5 minutes at 46 rpm.

3) Black toner example A2 for replenishment
・ Binder resin: 100 parts of polyester resin (Propylene oxide adduct of bisphenol A, polyester synthesized from terephthalic acid and succinic acid derivative)
Charge control agent: zinc salicylate (Bontron E84, Orient Chemical) 2 parts Release agent: 3.5 parts carnauba wax Coloring agent: carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7.5 parts After preliminarily kneading the prescribed amount with a mixer, melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, the toner was classified to obtain a toner having a weight average particle diameter of 6.7 μm. In order to round this toner, it was mechanically treated at 12,000 rpm for 10 minutes with a hybridizer manufactured by Nara Machinery, and a toner having an average circularity of toner particles of 0.95 was obtained.
Black for replenishment by mixing 0.8 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.4 part of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with respect to 100 parts by weight of the toner. Toner A2 was produced.
Developer and replenishment toner are set in the apparatus of FIG. In addition, the following setting was made, and a paper feeding test of 50,000 sheets was performed. The results are in Table 1.
1. Photoconductor linear velocity: 230 mm / sec
2. The surface potential of the photoreceptor is 380 V in the development area.
3. Distance between photoconductor and developing sleeve: 0.4 mm
4). The developing sleeve rotates at 1.7 times the linear velocity of the photoreceptor.
5. Development sleeve doctor gap: 0.5 mm
6). Fixing temperature: set to 165 ° C. 7. Toner density control of the two-component developer forms an electrostatic latent image of a reference density pattern on the photoconductor, develops the electrostatic latent image, and enables the reference density pattern. After the visual image is formed, the reflected light of the visible image is detected by the light detection element. Based on the detected value, the detected value is compared with a reference value, a toner density control signal corresponding to the comparison result is output, and the toner density (toner replenishment) of the developing unit is controlled. .

Example 2
1) Black toner example A3 for initial developer
・ Binder resin: 100 parts of polyester resin (Propylene oxide adduct of bisphenol A, polyester synthesized from terephthalic acid and succinic acid derivative)
Charge control agent: zinc salicylate (Bontron E84, Orient Chemical) 2 parts Release agent: 3.5 parts carnauba wax Coloring agent: carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7.5 parts After preliminarily kneading the prescribed amount with a mixer, melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, the toner was classified to obtain a toner having a weight average particle diameter of 6.8 μm. The average circularity of the toner particles was 0.89.
An initial developer is prepared by mixing 0.8 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.4 part of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with 100 parts by weight of the toner. A black toner A3 was prepared.

2) Example of magnetic carrier Z2
A coating solution was prepared according to the following formulation.
-Silicon resin SR2411 (solid content 20%, manufactured by Toray Dow Corning) 300 parts-Toluene 1200 parts The above liquid was put in a rotating disk type fluidized bed coating apparatus together with 5 kg of ferrite carrier having an average particle size of 50 µm to coat the carrier. Thereafter, the film was aged by heating at 250 ° C. for 2 hours to obtain a magnetic carrier.
Put 917g of magnetic carrier Z2 and 83g of black toner A1 in a 1L container so that the total amount of the toner and carrier obtained above is 1000g, respectively, and turn on a shaker shaker mixer T2F type (Shinmaru Enterprise Co., Ltd. The initial developer having a toner concentration of 8.3% was prepared by mixing for 5 minutes at 46 rpm.

3) Black toner example A4 for replenishment
・ Binder resin: 100 parts of polyester resin (Propylene oxide adduct of bisphenol A, polyester synthesized from terephthalic acid and succinic acid derivative)
Charge control agent: zinc salicylate (Bontron E84, Orient Chemical) 2 parts Release agent: 3.5 parts carnauba wax Coloring agent: carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7.5 parts After preliminarily kneading the prescribed amount with a mixer, melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, classification was performed to obtain a toner having a weight average particle diameter of 9.5 μm. In order to round this toner, it was mechanically treated at 12,000 rpm for 10 minutes with a hybridizer manufactured by Nara Machinery, and a toner having an average circularity of toner particles of 0.95 was obtained.
Black for replenishment by mixing 0.7 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.35 parts of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with respect to 100 parts by weight of the toner. Toner A4 was produced. Thereafter, the results of the same test as in Example 1 are as shown in Table 1.

Example 3
1) Black toner example A5 for initial developer
・ Binder resin: 100 parts of polyester resin (polyester synthesized from terephthalic acid and succinic acid derivative of propylene oxide adduct of bisphenol A)
Charge control agent: zinc salicylate (Bontron E84, Orient Chemical) 2 parts Release agent: 3.5 parts carnauba wax Coloring agent: carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7.5 parts After preliminarily kneading the prescribed amount with a mixer, melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, the toner was classified to obtain a toner having a weight average particle diameter of 4.0 μm. The average circularity of the toner particles was 0.88.
An initial developer is prepared by mixing 1.1 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.5 part of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with 100 parts by weight of the toner. A black toner A5 was prepared.

2) Example of magnetic carrier Z3
A coating solution was prepared according to the following formulation.
-Silicon resin SR2411 (solid content 20%, manufactured by Tore Dow Corning) 500 parts-Toluene 1200 parts The above liquid was put in a rotating disk type fluidized bed coating apparatus together with 5 kg of ferrite carrier having an average particle size of 30 µm to coat the carrier. Thereafter, the film was aged by heating at 250 ° C. for 2 hours to obtain a magnetic carrier.
Put 912 g of magnetic carrier Z3 and 88 g of black toner A1 in a 1 L container so that the total amount of the toner and carrier obtained above is 1000 g, respectively, and use a tumbler shaker mixer T2F type (Shinmaru Enterprise Co., Ltd.) The initial developer having a toner concentration of 8.8% was prepared by mixing for 5 minutes at 46 rpm.

3) Black toner example A6 for replenishment
・ Binder resin: 100 parts of polyester resin (polyester synthesized from terephthalic acid and succinic acid derivative of propylene oxide adduct of bisphenol A)
Charge control agent: zinc salicylate (Bontron E84, Orient Chemical) 2 parts Release agent: 3.5 parts carnauba wax Coloring agent: carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7.5 parts After preliminarily kneading the prescribed amount with a mixer, melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, classification was performed to obtain a toner having a weight average particle diameter of 5.0 μm. In order to round the toner, mechanical treatment was performed at 12,000 revolutions for 30 minutes with a hybridizer manufactured by Nara Machinery, and toner with an average circularity of toner particles of 0.97 was obtained.
Black for replenishment by mixing 0.8 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.4 part of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with respect to 100 parts by weight of the toner. Toner A2 was produced. Thereafter, the results of the same test as in Example 1 are as shown in Table 1.

Example 4
1) Black toner example A7 for initial developer
・ Binder resin: 100 parts of polyester resin (Propylene oxide adduct of bisphenol A, polyester synthesized from terephthalic acid and succinic acid derivative)
Charge control agent: zinc salicylate (Bontron E84, Orient Chemical) 2 parts Release agent: 3.5 parts carnauba wax Coloring agent: carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7.5 parts After preliminarily kneading the prescribed amount with a mixer, melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, the toner was classified to obtain a toner having a weight average particle diameter of 6.5 μm. The average circularity of the toner particles was 0.89.
An initial developer is prepared by mixing 0.8 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.4 parts of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with respect to 100 parts by weight of the toner. A black toner A7 was prepared.

2) Example of magnetic carrier Z3
A coating solution was prepared according to the following formulation.
-Silicon resin SR2411 (solid content 20%, manufactured by Toray Dow Corning) 250 parts-Toluene 1200 parts The above liquid was put into a rotating disk type fluidized bed coating apparatus together with 5 kg of ferrite carrier having an average particle diameter of 60 µm to coat the carrier. Thereafter, the film was aged by heating at 250 ° C. for 2 hours to obtain a magnetic carrier.
Put 935 g of magnetic carrier Z3 and 65 g of black toner A1 in a 1 L container so that the total amount of toner and carrier obtained above is 1000 g, respectively, and use a tumbler shaker mixer T2F type (Shinmaru Enterprise Co., Ltd.) The initial developer having a toner concentration of 6.5% was prepared by mixing for 5 minutes at 46 rpm.

3) Black toner example A8 for replenishment
Binder resin: Polyester resin (Propylene oxide adduct of bisphenol A, polyester synthesized from terephthalic acid and succinic acid derivative) 100 parts Charge control agent: Zinc salicylate (Bontron E84, Orient Chemical) 2 parts Release agent : Carnauba wax 3.5 parts Colorant: Carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7.5 parts The above prescription was pre-kneaded with a mixer, and then melt-kneaded with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, classification was performed to obtain a toner having a weight average particle diameter of 9.5 μm. In order to round this toner, it was mechanically treated at 12,000 rpm for 10 minutes with a hybridizer manufactured by Nara Machinery, and a toner having an average circularity of toner particles of 0.95 was obtained.
Black for replenishment by mixing 0.7 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.35 parts of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with respect to 100 parts by weight of the toner. Toner A4 was produced. Thereafter, the results of the same test as in Example 1 are as shown in Table 1.

Example 5
1) Black toner example A9 for initial developer
Example 1 was the same as Example 1 except that only the charge control agent: zinc salicylate (Bontron E84, Orient Chemical) was replaced with a metal-containing azo dye (Bontron S-34, Orient Chemical) in the toner formulation. Thus, black toner example A9 for initial developer was prepared.

2) Using the magnetic carrier example Z3 of Example 1 as the carrier, an initial developer was prepared in the same manner as in Example 1 with the black toner example A9.

3) Black toner example A10 for replenishment
Example 1 is the same as Example 1 except that only the charge control agent: zinc salicylate (Bontron E84, Orient Chemical) is replaced with a metal-containing azo dye (Bontron S-34, Orient Chemical) in the toner formulation. Thus, an initial developer black toner example A10 was prepared. Thereafter, the results of the same test as in Example 1 are as shown in Table 1.

Example 6
1) Black toner example A11 for initial developer
Example 1 is the same as Example 1 except that only the charge control agent: zinc salicylic acid salt (Bontron E84, Orient Chemical) is replaced with a fluorine-containing quaternary ammonium salt (VP434, manufactured by Clant Corporation) in the toner formulation. Thus, an example black toner A11 for an initial developer was prepared.

2) Using the magnetic carrier example Z3 of Example 1 as the carrier, an initial developer was prepared in the same manner as in Example 1 with the black toner example A9.

3) Black toner example A12 for replenishment
Example 1 is the same as Example 1 except that the charge control agent: zinc salicylate (Bontron E84, Orient Chemical) is replaced with fluorine-containing quaternary ammonium (VP434, manufactured by Clant Corporation) in the toner formulation. A black toner example A12 for initial developer was prepared. Thereafter, the results of the same test as in Example 1 are as shown in Table 1.

Example 7
Color toner example:
(1) Production Example of Masterbatch Pigment Production example 1 of yellow toner masterbatch
Binder resin Polyester resin A 50 parts (Polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, Tg: 60 ° C)
Colorant Imidazolone yellow pigment (C.I. Pigment yellow 180) 50 parts Water 30 parts The above raw materials are mixed with a Henschel mixer and then kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. -A master batch pigment was obtained.
2. Production example 2 of magenta toner master batch
Binder resin Polyester resin A 50 parts (Polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, Tg: 60 ° C)
Colorant Quinacridone-based magenta pigment (CI Pigment Red122) 50 parts Water 30 parts The above raw materials are mixed with a Henschel mixer, and then kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. -A master batch pigment was obtained.
3. Cyan toner master batch production example 3
Binder resin Polyester resin A 50 parts (Polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, Tg: 60 ° C)
Colorant Copper phthalocyanine cyan pigment (C.I. Pigment Blue 15: 3) 50 parts Water 30 parts The above raw materials are mixed in a Henschel mixer and then kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. To obtain a cyan masterbatch pigment.
4). Black toner masterbatch production example 3
Binder resin Polyester resin A 50 parts (Polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, Tg: 60 ° C)
Colorant Caron Black 50 parts Water 30 parts The above raw materials were mixed in a Henschel mixer and then kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. to obtain a black masterbatch pigment.

(2) Color toner production example 1) Initial developer yellow toner example A13
・ Binder resin: 100 parts of polyester resin (polyester synthesized from terephthalic acid and succinic acid derivative of propylene oxide adduct of bisphenol A)
-Charge control agent: Zinc salicylate (Bontron E84, Orient Chemical) 2 parts-Mold release agent: 3.0 parts carnauba wax-Colorant: 12 parts yellow masterbatch pigment After pre-kneading the above prescription amount with a mixer Melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, the toner was classified to obtain a toner having a weight average particle diameter of 5.5 μm. The average circularity of the toner particles was 0.88.
An initial developer is prepared by mixing 1.0 part of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.5 part of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with 100 parts by weight of the toner. A black toner A13 was prepared.

2) Example of magnetic carrier Z1
A coating solution was prepared according to the following formulation.
-Silicon resin SR2411 (solid content 20%, manufactured by Tore Dow Corning) 450 parts-Toluene 1200 parts The above liquid was placed in a rotating disk type fluidized bed coating apparatus together with 5 kg of ferrite carrier having an average particle size of 35 µm to coat the carrier. Thereafter, the film was aged by heating at 250 ° C. for 2 hours to obtain a magnetic carrier Z1.
Put 912 g of magnetic carrier Z1 and 88 g of yellow toner A13 in a 1 L container so that the total amount of toner and carrier obtained above is 1000 g, respectively, and use a shaker shaker mixer T2F type (Shinmaru Enterprise Co., Ltd.) The initial developer having a toner concentration of 7.4% was prepared by mixing for 5 minutes at 46 rpm.

3) Example of replenishing yellow toner A14
・ Binder resin: 100 parts of polyester resin (polyester synthesized from terephthalic acid and succinic acid derivative of propylene oxide adduct of bisphenol A)
-Charge control agent: Zinc salicylate (Bontron E84, Orient Chemical) 2 parts-Mold release agent: 3.0 parts carnauba wax-Colorant: 12 parts yellow masterbatch pigment After pre-kneading the above prescription amount with a mixer Melt kneading was performed with a three-roll mill. After cooling, this was coarsely pulverized to about 0.5 to 3 mm and then pulverized by an IDS2 type jet pulverizer. Thereafter, the toner was classified to obtain a toner having a weight average particle diameter of 6.5 μm. In order to round the toner, mechanical treatment was performed at 12,000 revolutions for 30 minutes with a hybridizer manufactured by Nara Machinery, and toner with an average circularity of toner particles of 0.97 was obtained.
Yellow for replenishment by mixing 0.8 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.) and 0.4 parts of titanium oxide (MT-150A; manufactured by Teica Co., Ltd.) with respect to 100 parts by weight of the toner. Toner A14 was produced.

Similar to the yellow toner, a developer was also prepared with the same carrier used for the initial agent toner, the replenishing toner, and the yellow, except that the colorant master batch was changed to magenta, cyan and black.
4) Magenta toner example A15 for initial developer
5) Replenishment magenta toner example A16
6) Cyan toner example A17 for initial developer
7) Supply cyan toner example A18
8) Black toner example A19 for initial developer
9) Black toner example A20 for replenishment
Developer and replenishment toner are set in the apparatus of FIG. In addition, the following setting was made, and a paper feeding test of 50,000 sheets was performed. The results are in Table 1.
1. Photoconductor linear velocity: 162 mm / sec
2. The surface potential of the photoreceptor is 350 V in the development area.
3. Distance between photoconductor and developing sleeve: 0.4 mm
4). The developing sleeve rotates at 1.8 times the linear velocity of the photoreceptor.
5. Development sleeve doctor gap: 0.5 mm
6). Fixing temperature: set to 170 ° C. 7. Toner density control of the two-component developer is to form an electrostatic latent image of a reference density pattern on the photosensitive member, develop the electrostatic latent image, and enable the reference density pattern. After the visual image is formed, the reflected light of the visible image is detected by the light detection element. Based on the detected value, the detected value is compared with a reference value, a toner density control signal corresponding to the comparison result is output, and the toner density (toner replenishment) of the developing unit is controlled. .

Example 8
A test was performed using the developer of Example 7 except that the test machine in Example 7 was changed to that shown in FIGS. 4 to 5. As a result, a result similar to that of Example 7 was obtained.

Example 9
Example of toner by crosslinking and / or extension reaction in aqueous solvent (Example of toner for initial agent)
1) Black toner example A24
~ Synthesis of organic fine particle emulsion ~
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30; manufactured by Sanyo Chemical Industries), 166 parts of methacrylic acid, butyl acrylate When 110 parts and 1 part of ammonium persulfate were charged and stirred at 3800 rpm for 30 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 4 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 6 hours to obtain an aqueous dispersion of a vinyl resin (methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt copolymer). A liquid [fine particle dispersion 1] was obtained. The volume average particle size of the [fine particle dispersion 1] measured by a laser diffraction particle size distribution analyzer (LA-920; manufactured by Shimadzu Corp.) was 110 nm. A portion of [Fine Particle Dispersion 1] was dried to isolate the resin component. The Tg of the resin was 58 ° C., and the weight average molecular weight was 130,000.

-Adjustment of aqueous phase-
990 parts of water, 83 parts of [fine particle dispersion 1], 37 parts of a 48.3% aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7; manufactured by Sanyo Kasei Kogyo Co., Ltd.) and 90 parts of ethyl acetate were mixed and stirred. A liquid was obtained. This is designated as [Aqueous Phase 1].

~ Synthesis of low molecular weight polyester ~
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts terephthalic acid, 46 parts adipic acid and dibutyl Put 2 parts of tin oxide, react at normal pressure and 230 ° C for 7 hours, and further react at 5-15 hours under reduced pressure of 10 to 15 mmHg. By reacting for 3 hours, [low molecular weight polyester 1] was obtained. [Low molecular polyester 1] had a number average molecular weight of 2,300, a weight average molecular weight of 6,700, Tg of 43 ° C., and an acid value of 25.

~ Synthesis of intermediate polyester ~
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, 22 parts of trimellitic anhydride Then, 2 parts of dibutyltin oxide was added, reacted at 230 ° C. under normal pressure for 7 hours, and further reacted at reduced pressure of 10 to 15 mmHg for 5 hours to obtain [Intermediate Polyester 1]. [Intermediate Polyester 1] had a number average molecular weight of 2200, a weight average molecular weight of 9700, Tg of 54 ° C., an acid value of 0.5, and a hydroxyl value of 52.
Next, 410 parts of [Intermediate polyester 1], 89 parts of isophorone diisocyanate and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. Polymer 1] was obtained. [Prepolymer 1] had a free isocyanate weight percentage of 1.53%.

~ Synthesis of ketimine ~
In a reaction vessel equipped with a stirrer and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 4 and a half hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 417.

~ Master batch synthesis ~
Add 1200 parts of water, 540 parts of carbon black (Printex35; manufactured by Dexa) (DBP oil absorption = 42 ml / 100 mg, pH = 9.5), 1200 parts of polyester resin, and mix with a Henschel mixer (manufactured by Mitsui Mining). The mixture was kneaded for 1 hour at 130 ° C. using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 1].

~ Preparation of oil phase ~
In a container equipped with a stir bar and a thermometer, 378 parts of [Low molecular weight polyester 1], 100 parts of Carnauba WAX, and 947 parts of ethyl acetate were charged, heated to 80 ° C. with stirring, and kept at 80 ° C. for 5 hours. Cooled to 30 ° C. in 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were placed in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Material solution 1] 1324 parts were transferred to a container, and using a bead mill (Ultra Visco Mill; manufactured by Imex Co., Ltd.), a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads were 80% by volume. Carbon black and WAX were dispersed under conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [low molecular weight polyester 1] was added, followed by two passes with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1]. The solid content concentration of [Pigment / WAX Dispersion 1] (130 ° C., 30 minutes) was 50%.

~ Emulsification, solvent removal ~
[Pigment / WAX Dispersion 1] 749 parts, [Prepolymer 1] 115 parts, [Ketimine Compound 1] 2.9 parts in a container, and 2 at 5,000 rpm with a TK homomixer (manufactured by Tokushu Kika) After mixing for 1 minute, 1200 parts of [Aqueous Phase 1] was added to the container and mixed with a TK homomixer at a rotation speed of 20,000 rpm for 25 minutes to obtain [Emulsion Slurry 1].
[Emulsion slurry 1] was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C for 8 hours, aging was carried out at 45 ° C for 7 hours to obtain [Dispersion slurry 1].

~ Washing, drying ~
[Dispersion Slurry 1] After filtering 100 parts under reduced pressure,
(I): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(II): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake of (I), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(III): 100 parts of 10% hydrochloric acid was added to the filter cake of (II), mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(IV): 300 parts of ion-exchanged water was added to the filter cake of (III), mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered twice to obtain [filter cake 1]. It was.
[Filter cake 1] was dried at 45 ° C. for 48 hours in a circulating dryer. 100 parts of this base toner was mixed with a mixer at a ratio of 0.6 part of zinc salicylate (E-84; manufactured by Orient Chemical Co., Ltd.). And sieved with a mesh of 75 μm, weight average particle size (D4) 5.1 μm, number average particle size (Dn) 4.6 μm, D4 / Dn = 1.11, average circularity 0.97, shape factor SF− A toner having 1 = 135, shape factor SF-2 = 118, minor axis (r2) / major axis (r1) = 0.8, and thickness (r3) / minor axis (r2) = 0.9 was obtained.

~ External additive treatment ~
With respect to 100 parts by weight of the toner, 1.3 parts of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.), 0.5 part of titanium oxide (MT-150A; manufactured by Teica), silica fine powder (RX-50; Nippon Aerosil Co., Ltd.) was mixed at a ratio of 0.8 part to prepare black toner A24 for an initial agent.
For the preparation of the initial developer, the Z1 carrier of Example 1 is used as the toner and carrier obtained above. Put 915 g of magnetic carrier Z1 and 85 g of yellow toner A13 in a 1 L container so that the total amount of toner and carrier is 1000 g, and use a tumbler shaker mixer T2F type (manufactured by Shinmaru Enterprise-Prises Co., Ltd.) An initial developer having a toner concentration of 8.5% was prepared by mixing at a rotation speed of 46 rpm for 5 minutes.

2) Yellow toner example A21
In the synthesis of the master batch, C.I. I. A yellow toner 21 for an initial agent was prepared in the same manner as in black toner example A24 except that CI Pigment Yellow 180 (PV Fast Yellow HG; manufactured by Clariant) was used.
The base toner has a weight average particle diameter (D4) of 5.0 μm, a number average particle diameter (Dn) of 4.5 μm, D4 / Dn = 1.11, an average circularity of 0.97, a shape factor SF-1 = 132, and a shape. The coefficient SF-2 was 115, the minor axis (r2) / major axis (r1) was 0.8, and the thickness (r3) / minor axis (r2) was 0.9.
For the preparation of the initial developer, the Z1 carrier of Example 1 is used as the toner and carrier obtained above. Put 915 g of magnetic carrier Z1 and 85 g of yellow toner A13 in a 1 L container so that the total amount of toner and carrier is 1000 g, and use a tumbler shaker mixer T2F type (manufactured by Shinmaru Enterprise-Prises Co., Ltd.) An initial developer having a toner concentration of 8.5% was prepared by mixing at a rotation speed of 46 rpm for 5 minutes.

3) Magenta toner example A22
In the synthesis of the master batch, C.I. I. An initial magenta toner A22 was prepared in the same manner as in the black toner example A24 except that CI Pigment Red 122 (Hostaperm Pink E; manufactured by Clariant) was used.
The base toner has a weight average particle diameter (D4) of 5.0 μm, a number average particle diameter (Dn) of 4.5 μm, D4 / Dn = 1.16, an average circularity of 0.96, a shape factor SF-1 = 137, and a shape. The coefficient SF-2 was 117, the minor axis (r2) / major axis (r1) = 0.8, and the thickness (r3) / minor axis (r2) = 0.9.
For the preparation of the initial developer, the Z1 carrier of Example 1 is used as the toner and carrier obtained above. Put 915 g of magnetic carrier Z1 and 85 g of yellow toner A13 in a 1 L container so that the total amount of toner and carrier is 1000 g, and use a tumbler shaker mixer T2F type (manufactured by Shinmaru Enterprise-Prises Co., Ltd.) An initial developer having a toner concentration of 8.5% was prepared by mixing at a rotation speed of 46 rpm for 5 minutes.

4) Cyan toner example A23
In the synthesis of the master batch, C.I. I. An initial cyan toner A23 was prepared in the same manner as in the black toner example A24 except that CI Pigment Blue 15: 3 (Lionol Blue FG-7351; manufactured by Toyo Ink Co., Ltd.) was used.
The base toner has a weight average particle diameter (D4) of 5.0 μm, a number average particle diameter (Dn) of 4.5 μm, D4 / Dn = 1.13, an average circularity of 0.97, a shape factor SF-1 = 134, and a shape. The coefficient SF-2 was 115, the minor axis (r2) / major axis (r1) was 0.8, and the thickness (r3) / minor axis (r2) was 0.9.
For the preparation of the initial developer, the Z1 carrier of Example 1 is used as the toner and carrier obtained above. Put 915 g of magnetic carrier Z1 and 85 g of yellow toner A13 in a 1 L container so that the total amount of toner and carrier is 1000 g, and use a tumbler shaker mixer T2F type (manufactured by Shinmaru Enterprise-Prises Co., Ltd.) An initial developer having a toner concentration of 8.5% was prepared by mixing at a rotation speed of 46 rpm for 5 minutes.

(Supply toner production example)
1) Black toner example A28
In the process of “~ emulsification, desolvation” of the initial agent black toner example A24,
When obtaining [Emulsified Slurry 1], 1200 parts of [Aqueous Phase 1] was added to a container, and mixing with a TK homomixer at a rotation speed of 20,000 rpm for 25 minutes was changed to a rotation speed of 13,000 rpm for 25 minutes. Otherwise, the black toner example A28 for replenishment was obtained in the same manner as the initial agent black toner example A24. 100 parts of this base toner was mixed with a mixer at a ratio of 0.6 part of zinc salicylate (E-84; manufactured by Orient Chemical Co., Ltd.). And sieved with a mesh of 75 μm, weight average particle size (D4) 5.7 μm, number average particle size (Dn) 5.1 μm, D4 / Dn = 1.11, average circularity 0.97, shape factor SF− A toner having 1 = 135, shape factor SF-2 = 118, minor axis (r2) / major axis (r1) = 0.8, and thickness (r3) / minor axis (r2) = 0.9 was obtained.

~ External additive treatment ~
1.0 part of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.), 0.4 part of titanium oxide (MT-150A; manufactured by Teica Co.), silica fine powder (RX-50; Nippon Aerosil Co., Ltd.) was mixed at a ratio of 0.6 part to prepare black toner A28 for replenishment.

2) Example of replenishing yellow toner A25
In the synthesis of the master batch, C.I. I. A replenishment yellow toner A25 was prepared in the same manner as in Replenishment black toner example A28, except that CI Pigment Yellow 180 (PV Fast Yellow HG; manufactured by Clariant) was used.
The base toner has a weight average particle diameter (D4) of 5.7 μm, a number average particle diameter (Dn) of 5.1 μm, D4 / Dn = 1.11, an average circularity of 0.97, a shape factor SF-1 = 132, and a shape. The coefficient SF-2 was 115, the minor axis (r2) / major axis (r1) was 0.8, and the thickness (r3) / minor axis (r2) was 0.9.

~ External additive treatment ~
1.0 part of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.), 0.4 part of titanium oxide (MT-150A; manufactured by Teica Co.), silica fine powder (RX-50; Nippon Aerosil Co., Ltd.) was mixed at a ratio of 0.6 part to prepare a replenishing yellow toner A25.

3) Magenta toner example A26
In the synthesis of the master batch, C.I. I. A replenishing magenta toner A26 was produced in the same manner as in the black toner example A28 except that CI Pigment Red 122 (Hostaperm Pink E; manufactured by Clariant) was used.
The base toner has a weight average particle diameter (D4) of 5.7 μm, a number average particle diameter (Dn) of 5.1 μm, D4 / Dn = 1.16, an average circularity of 0.96, a shape factor SF-1 = 137, and a shape. The coefficient SF-2 was 117, the minor axis (r2) / major axis (r1) = 0.8, and the thickness (r3) / minor axis (r2) = 0.9.

~ External additive treatment ~
1.0 part of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.), 0.4 part of titanium oxide (MT-150A; manufactured by Teica Co.), silica fine powder (RX-50; Nippon Aerosil Co., Ltd.) was mixed at a ratio of 0.6 part to prepare magenta toner A26 for replenishment.

4) Cyan toner example A27
In the synthesis of the master batch, C.I. I. A replenishing cyan toner A27 was produced in the same manner as in black toner example A24 except that CI Pigment Blue 15: 3 (Lionol Blue FG-7351; manufactured by Toyo Ink Co., Ltd.) was used.
The base toner has a weight average particle diameter (D4) of 5.0 μm, a number average particle diameter (Dn) of 4.5 μm, D4 / Dn = 1.13, an average circularity of 0.97, a shape factor SF-1 = 134, and a shape. The coefficient SF-2 was 115, the minor axis (r2) / major axis (r1) was 0.8, and the thickness (r3) / minor axis (r2) was 0.9.

~ External additive treatment ~
For 100 parts by weight of the toner, 1.0 part of silica fine powder (R972; manufactured by Nippon Aerosil Co., Ltd.), 0.4 part of titanium oxide (MT-150A; manufactured by Teica), silica fine powder (RX-50; Nippon Aerosil Co., Ltd.) was mixed at a ratio of 0.6 part to prepare a replenishing cyan toner A27.
When the initial developer and the replenishing toner were used and tested in the same manner as in Example 7, the results shown in Table 1 were obtained.

Example 10
In Example 7, the particle size of the initial toner of yellow toner, magenta toner, cyan toner and black toner was changed from 5.5 μm to 5.0 μm. Further, an initial agent toner and a developer were prepared in the same manner as in Example 7 except that the toner density of the developer was changed from 8.5% to 9.0% for each color. The replenishment toner was tested in the same manner as in Example 9 using the yellow toner, magenta toner, cyan toner and black toner of Example 9, and the results shown in Table 1 were obtained.

Comparative Example 1
The black toner A1 for initial developer, the magnetic carrier example 1 and the black toner A2 for replenishment of Example 1 are used. Put 948 g of magnetic carrier Z1 and 52 g of black toner A1 in a 1 L container so that the total amount of toner and carrier is 1000 g, and use a tumbler shaker mixer T2F type (manufactured by Shinmaru Enterprise Co., Ltd.) An initial developer having a toner concentration of 5.2% was prepared by mixing at a rotation speed of 46 rpm for 5 minutes. (The toner concentration is lower than that of Example 1. Example 1 is 7.4%.) The results of testing in the same manner as in Example 1 using this initial agent and black toner A2 for replenishment are shown in Table 1. It seems. Since the Q / M of the start was high, the image density was low, the transferability was not good, and the cleaning property was not good.

Comparative Example 2
The black toner A1 for initial developer, the magnetic carrier example 1 and the black toner A2 for replenishment of Example 1 are used. 920 g of the magnetic carrier Z1 and 80 g of the black toner A1 are put in a 1 L container so that the total amount of the toner and the carrier becomes 1000 g, respectively, and is used with a tumbler shaker mixer T2F type (manufactured by Shinmaru Enterprise-Prises Co., Ltd.) An initial developer having a toner concentration of 8.0% was prepared by mixing at 46 rpm for 5 minutes. (Toner concentration is higher than Example 1. Example 1 is 7.4%.) Using this initial agent and the black toner A2 for replenishment, the test results in the same manner as Example 1 are shown in Table 1. It seems. Since the Q / M of the start is low, the image density is high. In addition, as the toner adhesion amount increased, the transferability test was not good and the cleaning performance was not good.

1 is a schematic configuration diagram of an image forming apparatus according to a first embodiment of the present invention. FIG. 4 is a diagram schematically illustrating the shape of a toner for explaining the shape factor SF-1 and the shape factor SF-2. FIG. 3 is a diagram schematically illustrating the shape of a toner according to the present invention. It is a schematic block diagram of the image forming apparatus which is 2nd embodiment of this invention. It is a schematic block diagram of the image forming apparatus which is 3rd embodiment of this invention.

Explanation of symbols

1 Photosensitive drum (image carrier)
2 Main charger (charging means)
4 Developing means 4a Developing tank 4b Toner replenishing section 4c Recycled toner hopper 4d Recovery tank 5a Transfer charger 5b Separating charger 7 Toner conveying section 8 Cleaning means 9 Fixing means 40 Developing roller 41 Stirring screw 42 Stirring screw 43 Toner cartridge 44 Roller 45 Second supply roller 46 Mesh 50 Intermediate transfer belt 51 Primary transfer means (support roller)
52 Support Roller 53 Support Roller 54 Support Roller 55 Support Roller 56 Support Roller 57 Intermediate Transfer Belt Cleaning Means 58 Cleaning Blade 61 Secondary Transfer Roller 62 Secondary Transfer Belt 63 Support Roller 64 Support Roller 65 Support Roller 66 Transport Belt 71 Second Toner Conveying coil 80 Cleaning blade 81 Toner collection chamber 82 First toner conveying coil L Exposure light

Claims (22)

In the image forming method including at least a step of developing the electrostatic latent image on the image carrier with a two-component developer, and a step of cleaning the toner on the image carrier with a cleaning blade, the developing step includes an initial developer. The weight-average particle diameter of the toner contained in the toner comprises a developer smaller than the replenishment toner, and the toner coverage of the initial developer with respect to the carrier of the developer is 55 to 75%. The toner included in the initial developer used in the development step has a weight average particle diameter of 4.0 to 7.0 μm, and a replenishment toner has a weight average particle diameter of 5.0 to 9.5 μm. The image forming method according to claim 1. The image forming method according to claim 1, wherein an average circularity of toner contained in the initial developer used in the developing step is 0.93 or less. The image forming method according to claim 1, further comprising a toner recycling step in which the toner collected in the cleaning step is returned to the developer in the developing step and reused. The toner contained in the initial developer used in the development step contains a charge control agent on the surface, and the charge control agent comprises an azo metal complex compound, a quaternary ammonium salt, a fluorine-containing quaternary ammonium salt, 5. The image forming method according to claim 4, wherein the image forming method is selected from the group consisting of salicylic acid metal complex compounds. The toner particles of the replenishing toner used in the developing step have a weight average particle diameter of 5.0 to 9.5 μm and a ratio of the weight average particle diameter (D4) to the number average particle diameter (Dn) (D4 / 6. The image forming method according to claim 1, wherein Dn) is in a range of 1.00 to 1.40. 7. The image forming method according to claim 1, wherein the toner particles of the replenishing toner used in the developing step have an average circularity of 0.94 or more. The toner particles of the replenishing toner used in the development step have a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180. 8. The image forming method according to any one of 1 to 7. The toner for replenishment used in the developing step is an aqueous medium containing a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent are dispersed in an organic solvent. The image forming method according to any one of claims 1 to 8, wherein the image forming method is obtained by dispersing and emulsifying in the form of liquid droplets therein and causing a crosslinking and / or elongation reaction. The toner particles of the replenishing toner used in the developing step have a substantially spherical shape, and the shape is defined by a major axis r1, a minor axis r2, and a thickness r3 (provided that r1 ≧ r2 ≧ r3). The ratio of the major axis r1 to the minor axis r2 (r2 / r1) is in the range of 0.5 to 1.0, and the ratio of the thickness r3 to the minor axis r2 (r3 / r2) is 0.7 to 1. The image forming method according to claim 1, wherein the image forming method is in a range of 0.0. The developing step is performed a plurality of times on a single image carrier corresponding to a plurality of colors of toner, and has a transfer step of sequentially transferring and superimposing a toner image on a transfer target after completion of each developing step. The image forming method according to claim 4, wherein: A primary transfer step of transferring a plurality of color toner images formed on a single or a plurality of image carriers onto an intermediate transfer member, and a step of cleaning the toner on the intermediate transfer member using a cleaning blade. The image forming method according to claim 4, further comprising: 13. The image forming method according to claim 11, wherein the toner particles contained in the initial developer used in the developing unit have a weight average particle diameter of 4.0 to 7.0 μm. 13. The image forming method according to claim 11, wherein the average circularity of the toner particles of the toner contained in the initial developer used in the developing unit is 0.93 or less. In the image forming apparatus having at least developing means for developing the electrostatic latent image on the image carrier with a two-component developer and cleaning means for cleaning the toner on the image carrier with a cleaning blade, the development In the means, the weight average particle diameter of the toner contained in the initial developer is smaller than the replenishment toner, and the toner coverage of the initial developer with respect to the carrier of the developer is 55 to 75%. Is provided with a plurality of transfer units corresponding to a plurality of color toners on a single image carrier, and further transferring and superimposing the toner images on the transfer target after completion of each development. Image forming apparatus. In the image forming apparatus having at least developing means for developing the electrostatic latent image on the image carrier with a two-component developer and cleaning means for cleaning the toner on the image carrier with a cleaning blade, the development In the means, the weight average particle diameter of the toner contained in the initial developer is made of a developer smaller than the replenishment toner, and the toner coverage of the initial developer with respect to the carrier of the developer is 55 to 75%. A primary transfer unit that transfers a plurality of color toner images formed on the plurality of image carriers onto an intermediate transfer member; and a cleaning unit that cleans the toner on the intermediate transfer member using a cleaning blade. An image forming apparatus. A process cartridge in which an image carrier and at least one means selected from a charging means, a developing means, and a cleaning means are integrally supported and are detachably formed in an image forming apparatus. 17. A process cartridge comprising: an image bearing member and a developing unit in the image forming apparatus according to 16, wherein the process cartridge is integrally supported and is detachable from the image forming apparatus. A toner used in a developing step of an electrophotographic process, wherein the toner is a replenishing toner used in the developing step of the image forming method according to any one of claims 1 to 8, and the weight of toner particles The average particle diameter is 3.0 to 7.0 μm, and the ratio (D4 / Dn) of the weight average particle diameter (D4) to the number average particle diameter (Dn) is in the range of 1.00 to 1.40. Features toner. The toner according to claim 18, wherein the toner particles of the toner have an average circularity of 0.94 or more. The toner according to claim 18 or 19, wherein the toner particles of the toner have a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180. In the toner, a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent is dispersed in an organic solvent is dispersed in the form of droplets in an aqueous medium. The toner according to any one of claims 18 to 20, wherein the toner is obtained by emulsification treatment and crosslinking and / or elongation reaction. The toner particles of the toner have a substantially spherical shape, and the shape is defined by a major axis r1, a minor axis r2, and a thickness r3 (where r1 ≧ r2 ≧ r3), and the major axis r1 and minor axis r2. (R2 / r1) is in the range of 0.5 to 1.0, and the ratio (r3 / r2) of the thickness r3 to the minor axis r2 is in the range of 0.7 to 1.0. The toner according to claim 18, wherein the toner is a toner.

Images