JP4335097B2 - Developer for developing electrostatic image and image forming apparatus - Google Patents

Description

  The present invention relates to a developer and a color developer used for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like, and an image forming apparatus loaded with the developer.

  In electrophotographic image formation, a latent image is formed by an electrostatic charge on an image carrier such as a photoconductive substance, and a charged toner particle is attached to the electrostatic latent image to form a visible image. After that, the toner image is transferred to a recording medium such as paper and fixed to form an output image. In recent years, copying and printer technologies using an electrophotographic system are rapidly expanding from monochrome to full color, and the full color market tends to expand. Color image formation by full-color electrophotography generally reproduces all colors by laminating three color toners of three primary colors, yellow, magenta, and cyan, or four color toners with black added thereto. . Therefore, in order to obtain a clear full color image with excellent color reproducibility, it is necessary to smooth the fixed toner image surface to some extent to reduce light scattering. For these reasons, the image gloss of conventional full-color copying machines or the like is often 10 to 50% of medium to high gloss.

  In general, as a method for fixing a dry toner image on a recording medium, a contact heating fixing method in which a roller or belt having a smooth surface is heated and pressed against the toner is frequently used. This method has high thermal efficiency and high-speed fixing, and is advantageous in that it can give gloss and transparency to the color toner. However, the surface of the heat-fixing member is brought into contact with the molten toner under pressure. The post-peeling causes a so-called offset phenomenon in which a part of the toner image adheres to the surface of the fixing roller and is transferred onto another image. In order to prevent this offset phenomenon, a method is generally adopted in which the surface of the fixing roller is made of silicone rubber or fluorine resin with excellent releasability, and then a release oil such as silicone oil is applied to the surface of the fixing roller. It had been. This method is extremely effective in preventing toner offset, but requires a device for supplying a release oil, which increases the size and cost of the fixing device. For this reason, in a monochrome toner, by adjusting the molecular weight distribution of the binder resin so that the melted toner does not break internally, the viscoelasticity at the time of melting of the toner is increased, and a release agent such as wax is further included in the toner. There is a tendency to employ a method in which the release oil is not applied to the fixing roller or the amount of oil applied is very small.

  However, as described above, in order to improve the color reproducibility of the color toner, it is necessary to smooth the surface of the fixed image, so the viscoelasticity at the time of melting must be lowered, and it is easier to offset than the glossy monochrome toner. Therefore, it is more difficult to make the fixing device oil-free and to apply a small amount. In addition, when a release agent is contained in the toner, the adhesion of the toner is increased and the transfer property to the transfer paper is lowered. Further, the release agent in the toner contaminates the frictional charging member such as a carrier to reduce the charging property. This causes a problem that the durability is lowered.

  Conventionally, binder resins such as polyester resins and epoxy resins that are easy to obtain gloss have been used for color toners. However, since these resins contain hydrophilic groups, the amount of charge changes with humidity. Has the disadvantage of being large. Furthermore, recently, there is a tendency to reduce the particle size of the toner in order to obtain high image quality, but polyester resins and epoxy resins are inferior in grindability compared to styrene resins that have been conventionally used as binder resins for monochrome toners. Has the disadvantages.

For example, Patent Document 1 discloses a non-magnetic one-component developer containing an ester wax having an endothermic peak due to DSC and DSC at 50 to 90 ° C. It is said that this provides excellent hot offset resistance, but ester wax does not have excellent compatibility with polyester resin, and the carrier spent or filming of the wax occurs during the development of the copying machine, resulting in durability. Cannot be obtained.
Patent Document 2 discloses a developer containing a polyester resin and an ester wax having an endothermic peak due to DSC at 70 to 90 ° C., but this also cannot improve the durability.
In this way, the oilless full color toner is a developer that has sufficient low-temperature fixability, hot offset resistance, glossiness, color saturation, and sufficient durability without filming. Not.

On the other hand, for the carrier, prevention of filming of toner components on the carrier surface, formation of a uniform carrier surface, prevention of surface oxidation, prevention of moisture sensitivity deterioration, extension of developer life, prevention of carrier adhesion to the photoreceptor surface, photosensitivity For the purpose of protecting the body from scratches or abrasion by the carrier, controlling the polarity of the charge, or adjusting the amount of charge, a hard and high-strength coating layer is usually provided by coating with an appropriate resin material. For example, those coated with a specific resin material (see Patent Document 3), those in which various additives are added to the coating layer (see Patent Documents 4 to 10), and further additives on the carrier surface Disclosed are those using a deposited film (Patent Document 11) and those using a coating film containing conductive particles larger than the coating film thickness (Patent Document 12). To have.
Patent Document 13 describes that a benzoguanamine-n-butyl alcohol-formaldehyde copolymer is used as a main component for a carrier coating material, and Patent Document 14 describes a carrier-coated cross-linked product of a melamine resin and an acrylic resin. The use as a material is described.

  However, durability and carrier adhesion suppression are still insufficient. Concerning durability, there are problems such as spent toner on the carrier surface, destabilization of the charge amount, and reduction of the coating layer due to film removal of the coating resin and accompanying resistance reduction. However, as the number of copies increases, the quality of the copied image deteriorates, which is a problem. Therefore, improvement is necessary.

Japanese Patent Laid-Open No. 2003-156876 JP 2000-181120 A JP 58-108548 A JP 54-1555048 A JP 57-40267 A JP 58-108549 A JP 59-166968 A Japanese Patent Publication No. 1-19584 Japanese Examined Patent Publication No. 3-628 JP-A-6-202381 JP-A-5-273789 JP-A-9-160304 JP-A-8-6307 Japanese Patent No. 2683624

  The present invention has been made in view of the above problems, and even with a fixing method in which a release oil is not applied to the fixing roller or the amount of oil applied is very small, it has sufficient offset prevention properties and at the same time is durable. An object of the present invention is to provide a developer for developing an electrostatic image capable of forming an excellent and fine image over a long period of time and capable of forming a color image having an appropriate image gloss and excellent color reproducibility. And It is another object of the present invention to provide an image forming apparatus loaded with the developer for developing an electrostatic charge image.

」、（２）「前記キャリア被覆層の結着樹脂（Ａ）が、少なくともアクリル樹脂及びシリコン樹脂を含むことを特徴とする前記第（１）項に記載の静電荷像現像用現像剤」、（３）「前記キャリア被覆層の結着樹脂（Ａ）が、アクリル樹脂とシリコン樹脂とからなり、該２種類の樹脂が層構造をなしていることを特徴とする前記第（１）項又は第（２）項に記載の静電荷像現像用現像剤」、（４）「前記キャリア被覆層中の前記粒子の総含有量が、被覆層組成成分の４０〜９５ｗｔ％であることを特徴とする前記第（１）項乃至第（３）項のいずれかに記載の静電荷像現像用現像剤」、（５）「前記キャリア被覆層に含有する粒子が、アルミナ、酸化チタン、酸化亜鉛、又はそれらに表面処理を施したもののいずれかの、単独或いは複数であることを特徴とする前記第（４）項に記載の静電荷像現像用現像剤」、（６）「前記キャリアの１ＫＯｅにおける磁気モーメントが、４０〜９０Ａｍ^２／ｋｇであることを特徴とする前記第（１）項乃至第（５）項のいずれかに記載の静電荷像現像用現像剤」、（７）「前記キャリアの重量平均粒径が２０〜６５μｍであり、９μｍ以下の粒径を有するキャリア粒子の含有率が３．０重量％以下であることを特徴とする前記第（１）項乃至第（６）項のいずれかに記載の静電荷像現像用現像剤」、（８）「前記結着樹脂（Ｂ）が、ポリエステル樹脂であることを特徴とする前記第（１）項乃至第（７）項のいずれかに記載の静電荷像現像用現像剤」により達成される。
また、上記課題は、本発明の（９）「前記トナーが、フルカラートナーであることを特徴とする前記第（１）項乃至第（８）項のいずれかに記載の静電荷像現像用カラー現像剤」により達成される。
また、上記課題は、本発明の（１０）「前記第（１）項乃至第（９）項のいずれかに記載の静電潜像現像用現像剤を収納したことを特徴とする容器」により達成される。
また、上記課題は、本発明の（１１）「前記第（１）項乃至第（９）項のいずれかに記載の静電潜像現像用現像剤を用いることを特徴とする画像形成方法」により達成される。
また、上記課題は、本発明の（１２）「少なくとも感光体と、帯電手段と、露光手段と、現像手段と、クリーニング手段とを有し、該現像手段は前記第（１）項乃至第（９）項のいずれかに記載の現像剤を用いるものであることを特徴とする画像形成装置」により達成される。
また、上記課題は、本発明の（１３）「像担持手段としての感光体、帯電手段、クリーニング手段より選ばれる少なくとも１つの手段を現像手段と一体に支持し、画像形成装置本体に着脱自在であるプロセスカートリッジであって、前記現像手段は、現像剤を保持し、該現像剤は前記第（１）項乃至第（９）項のいずれかに記載の現像剤であることを特徴とするプロセスカートリッジ」により達成される。
The present invention provides the following developer for developing an electrostatic image and an image forming apparatus loaded with the developer.
That is, the above-mentioned problem is (1) “a carrier having a carrier coating layer comprising at least a binder resin (A) and particles on the core material surface, wherein the binder resin (A) is at least an acrylic resin. A carrier having a particle diameter (D) of the particles and a film thickness (h) of the coating resin of 1 <[D / h] <10, at least a binder resin (B), a colorant, and the following formula: A developer for developing an electrostatic charge image, comprising: a toner containing a synthetic ester wax represented by (1) .

(2) "The developer for developing an electrostatic image according to (1) above, wherein the binder resin (A) of the carrier coating layer contains at least an acrylic resin and a silicon resin", (3) “The binder resin (A) of the carrier coating layer comprises an acrylic resin and a silicon resin, and the two types of resins have a layer structure, The developer for developing an electrostatic charge image according to item (2) ”, (4)“ the total content of the particles in the carrier coating layer is 40 to 95 wt% of the coating layer composition component, ” The developer for developing an electrostatic charge image according to any one of items (1) to (3) ”, (5)“ particles contained in the carrier coating layer are alumina, titanium oxide, zinc oxide, Or any of those subjected to surface treatment, alone or in plural Wherein the magnetic moments, characterized in that it is a 40~90Am ² / kg in the first (4) The electrostatic image developer according to claim ', (6) "1KOe of the carrier, characterized in that The developer for developing an electrostatic charge image according to any one of Items (1) to (5), (7) “Weight average particle diameter of the carrier is 20 to 65 μm, and the particle diameter is 9 μm or less. (6) The developer for developing an electrostatic charge image according to any one of (1) to (6) above, wherein the carrier particle content is 3.0% by weight or less. "the binder resin (B), electrostatic image developer according to any one of paragraph (1), second (7) sections, wherein the polyester resin" are more accomplished .
Further, the above problem is ( 9 ) in the present invention, wherein the toner is a full-color toner, and the electrostatic image developing color according to any one of the items (1) to ( 8 ), Achieved by "developer".
Further, the above object is achieved by ( 10 ) of the present invention, “a container containing the developer for developing an electrostatic latent image according to any one of (1) to ( 9 )”. Achieved.
In addition, the above-mentioned problem is ( 11 ) “image forming method using the developer for developing electrostatic latent image according to any one of (1) to ( 9 )” of the present invention. Is achieved.
Further, the above-described problem is ( 12 ) “At least the photosensitive member, the charging unit, the exposing unit, the developing unit, and the cleaning unit, and the developing unit includes the above-described (1) to (1). This is achieved by an image forming apparatus using the developer according to any one of 9 ).
In addition, the above-mentioned problem is solved by ( 13 ) “photosensitive member as image carrying means, charging means, cleaning means, and at least one means selected from the developing means, and is detachably attached to the image forming apparatus main body. A process cartridge, wherein the developing means holds a developer, and the developer is the developer according to any one of (1) to ( 9 ). Achieved by a "cartridge".

The developer of the present invention has a small amount of toner spent accumulated on the surface of the carrier and can obtain a stable charge amount, and since no significant film scraping of the binder resin (A) occurs, a stable electrical resistance can be obtained. No image deterioration occurs. Further, the offset property of the toner is improved, and the lowering of the durability inherent in the toner containing wax can be suppressed. In addition, in a developer using color toner, an image having an appropriate image gloss and excellent color reproducibility is obtained,
Therefore, as the number of copies increases, the image quality degradation of the generated copy image is greatly improved, and an excellent effect is achieved that a good image can be maintained for a long time.

Hereinafter, the present invention will be described in more detail.
As a result of continuing studies to solve the above-described problems of the prior art, the present inventors have obtained a carrier having a coating layer comprising at least a binder resin (A) and particles on the surface of the core, The binder resin (A) contains at least an acrylic resin, the particle diameter (D) of the particles and the film thickness (h) of the coating resin are 1 <[D / h] <10, and at least the binder resin It has been found that the improvement effect is remarkable when the developer for developing an electrostatic image is characterized by comprising (B) a toner containing a colorant and a synthetic ester wax.

  First, the carrier will be explained. Acrylic resin has strong adhesion and low brittleness, so it has a very excellent property of abrasion resistance, and it is difficult to cause deterioration such as coating film peeling and film peeling. The holding power of the particles contained in the film is also excellent due to the force, and a stable charge amount can be maintained. And since the particle diameter (D) and the film thickness (h) of the coating resin (A) are 1 <[D / h] <10, the particles are more convex than the coating film. By agitation for triboelectrically charging the developer, contact with a strong impact on the binder resin (A) due to friction with toner or friction between carriers can be reduced. As a result, it is possible to suppress film scraping of the binder resin (A), which is a location where charging occurs. In addition, since there are many particles that are more convex than the coating film on the carrier surface, it also exhibits a cleaning effect that efficiently scrapes off the spent component of the toner adhering to the carrier surface due to frictional contact between carriers, preventing toner spent can do. When [D / h] is 1 or less, the particles are buried in the binder resin (A). When [D / h] is 10 or more, the contact area between the particles and the binder resin (A) is small, so that a sufficient restraining force cannot be obtained and the particles are easily detached. On the other hand, the toner can have a wide fixing temperature range due to the effect of containing the synthetic ester wax, and a good effect on the spent resistance can be obtained by combining with the present carrier.

  Further, the effect of the carrier coating layer is remarkable because the binder resin (A) is a coating layer containing at least an acrylic resin and a silicon resin. As described above, acrylic resin has a very excellent property of abrasion resistance due to its strong adhesiveness and low brittleness, but on the other hand, it has a high surface energy, so it can be easily spent with toner. In the combination, problems such as a decrease in charge amount due to accumulation of toner component spent may occur. In this case, this problem can be solved by using together a silicon resin that has an effect that it is difficult to spend the toner component due to the low surface energy and the accumulation of the spent component is difficult to progress due to film scraping. However, since silicon resin has weak adhesiveness and high brittleness, it also has a weak point that it has poor wear resistance. Therefore, it is important to obtain a good balance between the properties of these two types of resins, which makes it difficult to spend. It is possible to obtain a coating film having wear characteristics.

  Specifically, in the coating film made of an acrylic resin and a silicon resin, the effect is remarkably obtained when the ratio of the acrylic resin is 10 to 90 wt%. This is not preferable when the ratio of the acrylic resin is less than 10 wt%, because most of the coating layer occupies the silicon resin component, resulting in deterioration of wear resistance due to the high brittleness that is a defect of the silicon resin. On the other hand, when the ratio of the acrylic resin exceeds 90 wt%, most of the coating layer occupies the acrylic resin component. Therefore, the toner component spent due to the high surface energy and the difficulty of film scraping, which are disadvantages of the acrylic resin, are caused. Is unfavorable as it accumulates.

Here, each coating resin will be described in detail.
First, regarding the acrylic resin, the term “acrylic resin” as used herein refers to a resin having an acrylic component, and is not particularly limited. In addition, it is possible to use the acrylic resin alone, but it is also possible to use at least one other component that undergoes a crosslinking reaction simultaneously. Examples of other components that undergo a crosslinking reaction include amino resins and acidic catalysts, but are not limited thereto.
In addition, the amino resin here refers to guanamine, melamine resin, and the like, but is not limited thereto. Moreover, what has a catalytic action can be used with an acidic catalyst here. For example, it has a reactive group such as a fully alkylated type, a methylol group type, an imino group type, and a methylol / imino group type, but is not limited thereto.

Next, regarding silicon resin, the silicon resin in the present invention refers to a generally known silicon resin, such as straight silicon consisting only of organosilosan bonds, alkyd, polyester, epoxy, acrylic, urethane, etc. However, the present invention is not limited to this.
Examples of commercially available straight silicon resins include KR271, KR255, and KR152 manufactured by Shin-Etsu Chemical, SR2400, SR2406, and SR2410 manufactured by Toray Dow Corning Silicon. In this case, it is possible to use the silicon resin alone, but it is also possible to simultaneously use other components that undergo a crosslinking reaction, charge amount adjusting components, and the like. Further, as modified silicone resins, KR206 (alkyd modified), KR5208 (acrylic modified), ES1001N (epoxy modified), KR305 (urethane modified) manufactured by Shin-Etsu Chemical, SR2115 (epoxy modified) manufactured by Toray Dow Corning Silicon Co., Ltd. , SR2110 (alkyd modified) and the like.

Furthermore, it has been found that the improvement effect is remarkable because the coating film made of acrylic resin and silicon resin has a layer structure. There are several functions required for the coating film of the carrier, such as the spent resistance function, the wear resistance function, and the adhesive function. However, there is no material that can satisfy these functions with one material. There is something with a good function. Therefore, when combining several kinds of materials with excellent functions, it is possible to form a coating film with excellent functions by making a layer structure that can maximize the specific function of each material. It seems to be possible. Specifically, by using an acrylic resin for the adhesive layer with the core material, the adhesiveness between the core material and the coating film is strengthened and the brittleness between the core material and the upper resin coating layer is low. It is thought that the impact resistance function is exhibited as an intermediate layer and the silicone resin layer is provided thereon, so that the spent resistance of the toner component is exhibited and the toner layer is improved. However, the present invention is not limited to this. .

  Furthermore, the effect is remarkable because the total content of the particles in the carrier coating film is in the range of 40 to 95 wt% of the coating film composition component. When the total content is less than 40 wt%, since the proportion of the particles is smaller than the proportion of the binder resin (A) on the surface of the carrier particles, a strong impact on the binder resin (A). Since the effect of relieving the contact accompanied by is small, sufficient durability cannot be obtained, which is not preferable. On the other hand, when the amount is more than 95 wt%, the proportion of the particles is excessive compared to the proportion of the binder resin (A) on the carrier surface. The proportion occupied is insufficient, and sufficient charging ability cannot be exhibited. In addition, since the amount of particles is too much compared to the amount of the binder resin (A), the ability to hold the particles by the binder resin (A) becomes insufficient, and the particles are easily detached, so that sufficient durability can be obtained. Not preferable. Further, although it is a technique described in JP-A-9-160304, which is not without similarities to the above-described present invention, the particle content range is significantly different from that of the present invention. "0.01 to 50 wt%", that is, "0.01 to 33.33 wt% of the coating film composition component" when converted to the content calculation method of the present invention. In this case, the durability is improved as compared with the conventional case. However, as mentioned above, since the proportion of the binder resin (A) on the surface of the carrier particles is smaller than that of the binder resin (A), the contact with strong impact on the binder resin (A) is alleviated. This is not preferable because the durability of the effect is small and sufficient durability cannot be obtained.

  In the present invention, the “particles” constituting the carrier coat film together with the binder resin (A) include metal powders, metal suboxides such as indium oxide and stannous oxide, metals such as zinc oxide, titanium oxide and alumina. Conductive non-metallic element particles such as oxide and carbon black, organometallic compounds such as metal hydroxides, inorganic salts and metal chelate compounds, non-metallic element particles such as silicon carbide and silicon nitride, thermosetting resin particles, ceramics Various kinds of particles such as particles, organic acid metal salts and organic pigments can be mentioned, and a mixture of a plurality of these particles may be used. The volume average particle diameter of the primary particles is 50 to 3000 nm, more preferably 100 to 1000 nm.

  Furthermore, as particles for the carrier coating layer (hereinafter sometimes referred to as coating film), any one of alumina, titanium oxide, zinc oxide, or those obtained by subjecting them to surface treatment can be used alone or in combination. The effect is remarkable. One of the reasons for including the particles is that the coating layer is protected from an external force applied to the carrier surface. If the particles are easily crushed or worn by this external force, the protective effect of the coating layer can be obtained initially, but it cannot be maintained over a long period of time, and stable quality cannot be obtained. Absent. Since the particles mentioned here have tough properties, they are strong against this external force, do not cause crack wear, and can maintain the protective effect of the coating layer over a long period of time. Further, the particle size is preferably 5 μm or less, and the location of the particles in the coating film is preferably present in the acrylic resin. The reason is that the particles can be held for a long time due to the strong adhesiveness of the acrylic resin, but it is not necessarily required to be present in the acrylic resin.

  It is also effective to contain carbon black in the coating resin (binder resin (A)) as necessary. The effect is remarkable, and it can be used as a regulator that lowers the resistance when the resistance is high in the case of a coating film composed of only the coating resin or the coating resin and particles. In general, when a carrier having a high resistance is used as a developer, on the image surface of a large area of a copy image, the image density at the center is very thin and only the edges are expressed deeply, so-called edge effect is sharply used. It becomes the image that was. In addition, when the image is a character or a thin line, the image is clear due to the edge effect. However, when the image is halftone, there is a defect that the image is very reproducible. Therefore, it is possible to obtain an excellent image by using the carbon book appropriately. Furthermore, it can also be used for a color carrier. In the case of a carrier for a color developer, a scraped film is mixed in the image, and if the scraped film has a dark color due to reasons such as containing carbon black, it becomes a defective image because it clearly stands out in the image, In the present invention, the coating resin has an acrylic resin, and as described above, since the acrylic resin has a property of being highly adhesive and difficult to scrape, the carbon black can be firmly held in the coating resin, and the resin This is because the carbon black is hardly detached from the carrier because it is difficult to scrape itself. In particular, the effect is great by dispersing carbon black in an acrylic resin. In the layer structure coating film, the effect is great by forming an acrylic resin film in which carbon black is dispersed in the lower layer and a silicon resin layer not containing carbon black in the upper layer. As used herein, carbon black may be any commonly used carrier or toner. On the other hand, in the case of a highly brittle resin such as silicon resin that can be easily scraped, if carbon black is contained in the coating resin, a scraped black film appears in the image, which becomes a defective image and cannot be used.

Furthermore, the effect is remarkable because the magnetic moment at 1 KOe of the carrier particles is 40 to 90 Am ² / kg.
This is because, within this range, the retention force between the carrier particles is appropriately maintained, so that the dispersion (mixing) of the toner into the carrier or developer is quickly and favorably improved. However, the magnetic moment at 1 KOe is 40 Am ^2. If it is less than / kg, carrier adhesion occurs due to insufficient magnetic moment, which is not preferable.
On the other hand, when the magnetic moment at 1 KOe exceeds 90 Am ² / kg, the ears of the developer formed at the time of development become too hard, so that the reproducibility of image details is poor and a fine image cannot be obtained, which is not preferable.

Furthermore, the effect is remarkable because the weight average particle diameter of the carrier is 20 to 65 μm and the content of the particles having a particle diameter of 9 μm or less is 3.0% by weight or less.
If the thickness is less than 20 μm, the uniformity of the particles is lowered, and carrier adhesion occurs, which is not preferable.
On the other hand, if it exceeds 65 μm, the reproducibility of image details is poor and a fine image cannot be obtained, which is not preferable.
When the content ratio of the particles having a particle diameter of 9 μm or less exceeds 3.0% by weight, as in the case where the weight average particle diameter is less than 20 μm as described above, there are many non-uniform particles.

  Furthermore, the effect is remarkable because the binder resin (B) of the toner is a polyester resin. In the case of a polyester resin and a synthetic ester wax, the low molecular weight component of the binder resin has good compatibility with the wax, and the wax can be included in the polyester resin to enhance the dispersion effect. As a result, it is possible to improve wax release, spent and filming due to poor dispersion and compatibility of wax without impairing hot offset resistance and releasability from the fixing separation claw. This is because the synthetic ester wax exists in a state in which it is appropriately compatible with the polyester resin, but is not completely compatible, so it is sharply melted from the resin by the heat energy at the time of fixing, and is excellent in releasability. For example, olefin wax has high compatibility with polyester, so that sufficient releasability cannot be obtained.

  The polyester resin used in the present invention is obtained by a polycondensation reaction between a polyvalent carboxylic acid component and a polyhydric alcohol component. The polyvalent carboxylic acid component includes divalent carboxylic acids and, if necessary, trivalent or higher carboxylic acids. Specific examples of the divalent carboxylic acids include (1) maleic acid, fumaric acid, succinic acid, adipic acid, sebacic acid, malonic acid, azelaic acid, mesaconic acid, citraconic acid, glutaconic acid, etc. Aliphatic dicarboxylic acids; (2) Cycloaliphatic dicarboxylic acids having 8 to 20 carbon atoms such as cyclohexanedicarboxylic acid and methylmedicic acid; (3) Carbon such as phthalic acid, isophthalic acid, terephthalic acid, toluene dicarboxylic acid, naphthalenedicarboxylic acid, etc. (4) alkyl or alkenyl succinic acid having a hydrocarbon group having 4 to 35 carbon atoms in the side chain such as isododecenyl succinic acid and n-dodecenyl succinic acid; And carboxylic acid anhydrides and lower alkyl (methyl, butyl, etc.) esters. Among these, the above (1), (3), (4) and anhydrides and lower alkyl esters of these dicarboxylic acids are preferable, and (anhydrous) maleic acid, fumaric acid, isophthalic acid, terephthalic acid, dimethyl terephthalate, n- More preferred is dodecenyl (anhydrous) succinic acid. Examples of tricarboxylic or higher polycarboxylic acids include (1) 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2- C7-20 aliphatic polycarboxylic acids such as methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid; (2) 1,2,4-cyclohexanetricarboxylic acid, etc. (3) 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, and 1,2 , 4-naphthalenetricarboxylic acid, pyromellitic acid, benzophenone tetracarboxylic acid and other aromatic polycarboxylic acids having 9 to 20 carbon atoms; Alkyl (methyl, butyl, etc.) ester. When using tricarboxylic or higher polycarboxylic acids, among these, (3) and its anhydrides and lower alkyl esters are preferred, but since the gloss and transparency tend to decrease, the amount used should be small. It is. Examples of the polyhydric alcohol component include dihydric alcohols such as (1) ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4. -C2-C12 alkylene glycol such as butenediol, 1,5-pentanediol, 1,6-hexanediol; (2) diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene Alkylene ether glycols such as glycol; (3) alicyclic diols having 6 to 30 carbon atoms such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A: and (4) bisphenol A, bisphenol F, bisphenol Bisphenols such as S; and, and (5) above bisphenols alkylene oxide (EO, PO, butylene oxide, etc.) 2-8 mole adducts. When using (B2), (1) and (5) are preferable among these, and (5) is more preferable. Among the above (5), EO and / or PO 2-4 mol adducts of bisphenol A are particularly preferable in terms of giving good offset resistance to the toner. Specific examples of trihydric or higher alcohols include (1) sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2, Number of coal cords such as 4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, etc. 3-20 Aliphatic polyhydric alcohols: (2) aromatic polyhydric alcohols having 6 to 20 carbon atoms such as 1,3,5-trihydroxylmethylbenzene, and these alkylene oxide adducts. When trihydric or higher alcohols are used, the compound (1) is preferable among them, and among them, glycerol, trimethylolpropane and pentaerythritol are preferable from the viewpoint of low cost. However, gloss and transparency tend to decrease. Therefore, the amount used should be small.

  Furthermore, the effect is remarkable because the synthetic ester wax is a synthetic ester wax having a long-chain branched structure. This has a long-chain branching structure that increases the melting point, thereby improving hot offset resistance (especially on the high temperature side) and releasability from the fixing separation claw, as well as improving spent and filming. it can.

  As the synthetic ester wax referred to in the present invention, a general synthetic ester wax can be used. Furthermore, although the following specific example is mentioned as a synthetic ester wax which has a long-chain branch structure, it is not limited to this. These can be used alone or in combination of two or more, but it is preferable to use those having a melting point in the range of 70 to 90 ° C. By setting the melting point to 70 ° C. or more, a toner having excellent transferability and durability can be obtained, and by setting the melting point to 90 ° C. or less, the toner can be melted quickly at the time of fixing and a reliable release effect can be exhibited. The amount of these release agents used is preferably 2 to 15% by weight based on the toner. If it is 2% by weight or less, the effect of preventing offset is insufficient, and if it is 15% by weight or more, transferability and durability are lowered. From the viewpoint of transferability and durability, it is preferable that the maximum dispersed particle diameter of the wax in the toner is a major axis diameter that is 1/2 or less of the maximum particle diameter of the toner, and more preferably, the maximum dispersed particle diameter of the wax is the major axis diameter. It is 1/3 or less of the maximum particle diameter of the toner. However, if the maximum dispersed particle diameter of the wax is 0.5 μm or less in terms of the major axis diameter, the wax will not easily ooze out during fixing and the offset prevention effect will be insufficient. The ester wax of the present invention is selected from among 14 to 30 carbon atoms, a linear saturated monocarboxylic acid whose one component is 60% by weight or more, and one component selected from among 14 to 30 carbon atoms. Esterified crude by a condensation reaction with a linear saturated monohydric alcohol having 2% by weight or more, or a C2-C30, one component of which is 80% by weight or more. Obtained by a process comprising adding a hydrocarbon solvent in a proportion of 5 to 100 parts by weight to 100 parts by weight of the crude esterified product and deoxidizing with an aqueous alkaline solution . In a preferred embodiment, the ester wax further comprises an alcohol solvent having 1 to 3 carbon atoms in addition to the hydrocarbon solvent in an amount of 3 to 50 parts by weight based on 100 parts by weight of the esterified crude product. It is obtained by a process including adding at a ratio and performing deoxidation using the alkaline aqueous solution. The ester wax of the present invention is selected from 14 to 30 carbon atoms, one component of which is 60% by weight or more of a linear saturated monocarboxylic acid, and one component selected from 14 to 30 carbon atoms. Esterification by a condensation reaction with a linear saturated monohydric alcohol that is 60% by weight or more, or a 2-6 valent polyhydric alcohol that is selected from among 2 to 30 carbon atoms and one component of which is 80% by weight or more. Obtaining a composition; and with respect to 100 parts by weight of the esterified composition, having a boiling point that is higher than the melting temperature of the esterified composition and not higher than 300 ° C., and has a specific gravity of 0.9 The above-mentioned water-soluble organic solvent is added at a ratio of 3 to 50 parts by weight, and is obtained by a process including deoxidation using an alkaline aqueous solution.

The ester wax of the present invention is an ester compound obtained from carboxylic acid (component a) and alcohol (component b). This carboxylic acid (component a) is a linear saturated monocarboxylic acid selected from 14 to 30 carbon atoms and one component is 60% by weight or more, and alcohol (component b) is 14 to 30 carbon atoms. Selected from the group consisting of a linear saturated monohydric alcohol (b1 component) whose one component is 60% by weight or more, or 2 to 6 valents whose one component is 80% or more selected from among 2 to 30 carbon atoms It is a polyhydric alcohol (b2 component).
Examples of the linear saturated monocarboxylic acid (component (a)) include myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, montanic acid, melicic acid and the like.
Examples of the linear saturated monohydric alcohol (component b1) include myristyl alcohol, cetyl alcohol, stearyl alcohol, aralkyl alcohol, behenyl alcohol, tetracosanol, hexacosanol, octacosanol, and triacontanol. It is done. Among the above divalent to hexavalent polyhydric alcohols (component b2), divalent alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, 1,20-eicosanji All, 1,30-triacontanediol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, spiroglycol, 1,4- Phenylene glycol, bisphenol A, hydrogenated bis Phenol A, and the like. Examples of the trivalent alcohol include 1,2,4-butanetriol, 1,2,5-pentanetriol, 2-methyl-1,2,4-butanetriol, glycerin, 2-methylpropanetriol, trimethylolethane, Examples include triethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene and the like. Examples of the tetravalent alcohol include 1,2,3,6-hexanetetrol and pentaerythritol. Examples of the pentavalent alcohol include glucose. Examples of the hexavalent alcohol include dipentaerythritol.
The ester wax of the present invention obtained from the carboxylic acid and alcohol shown above is composed of a linear saturated monocarboxylic acid and a linear saturated monohydric alcohol from the viewpoint of blocking resistance and storage stability of the toner containing the wax. In the case of an ester, the total number of carbon atoms of the main component ester is preferably 36 or more. The carbon number is more preferably 40 or more, and particularly preferably 44 or more. In consideration of the thermal melting behavior (sharp melt property) of the ester wax, the linear saturated monocarboxylic acid (component a) used as the raw material for the ester wax of the present invention, one component (main component) of the carboxylic acid and the component The total content of the main component and the linear saturated monocarboxylic acid having a carbon number of ± 2 is preferably 60% by weight or more. This content is more preferably 80% by weight or more, further preferably 90% by weight or more, particularly preferably 95% by weight or more, and most preferably 98% by weight or more. In a more preferred embodiment of the carboxylic acid content, the main component of the carboxylic acid is contained alone in a proportion of 60% by weight or more. This content is more preferably 80% by weight or more, further preferably 90% by weight or more, and most preferably 95% by weight or more. Among the alcohols (component b) used as the raw material for the ester wax, linear saturated monohydric alcohol (component b1) is also an alcohol having one component (main component) of the alcohol and the number of carbons of the main component ± 2. The total content is preferably 60% by weight or more. This content is more preferably 80% by weight or more, further preferably 90% by weight or more, particularly preferably 95% by weight or more, and most preferably 98% by weight or more. In a more preferred embodiment of the alcohol content, the main component of the alcohol is contained alone in a proportion of 60% by weight or more. This content is more preferably 80% by weight or more, further preferably 90% by weight or more, and most preferably 95% by weight or more. Regarding the divalent to hexavalent polyhydric alcohol (b2 component), it is preferable that one component (main component) of the polyhydric alcohol is contained in an amount of 80% by weight or more. This content is more preferably 85% by weight or more, further 90% by weight or more, and most preferably 95% by weight or more.

  Further, even when the toner is a full color toner, the effect is remarkable. This is because color characteristics become important in the case of full-color toner, but when wax is contained, depending on the type, the color may be hindered and the color reproducibility may be deteriorated. However, in the case of the synthetic ester wax referred to in the present invention, such a problem does not occur.

As the binder resin (B) in the present invention, conventionally known resins can be widely used in addition to the polyester resin, as binder resins used for toners such as color toners.
For example, styrene, parachlorostyrene, vinyl toluene, vinyl chloride, vinyl acetate, vinyl propionate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate , Isobutyl (meth) acrylate, dodecyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, ( 2-chloroethyl (meth) acrylate, (meth) acrylonitrile, (meth) acrylamide, (meth) acrylic acid, vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl methyl ketone, N-vinyl pyrrolidone, N-vinyl pyridine, Monomers such as butadiene Weight body, or a copolymer of two or more kinds of these monomers, or mixtures thereof. In addition, a polyol resin, a polyurethane resin, a polyamide resin, an epoxy resin, a rosin, a modified rosin, a terpene resin, a phenol resin, a hydrogenated petroleum resin, or the like can be used alone or in combination.

As the colorant used in the toner such as the color toner of the present invention, known pigments and dyes capable of obtaining yellow, magenta, cyan, and black toners can be used, and are not limited to those listed here.
Examples of yellow pigments include cadmium yellow, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa Yellow G, Hansa Yellow 10G, Benzidine Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, and Tartrazine Lake. Can be mentioned.
Examples of the orange pigment include molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, and indanthrene brilliant orange GK.
Examples of red pigments include Bengala, Cadmium Red, Permanent Red 4R, Resol Red, Pyrazolone Red, Watching Red Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B.
Examples of purple pigments include fast violet B and methyl violet lake.
Examples of blue pigments include cobalt blue, alkali blue, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated, fast sky blue, and indanthrene blue BC.
Examples of the green pigment include chrome green, chromium oxide, pigment green B, and malachite green lake.
Examples of black pigments include azine dyes such as carbon black, oil furnace black, channel black, lamp black, acetylene black, and aniline black, metal salt azo dyes, metal oxides, and composite metal oxides.
Moreover, these colorants can use 1 type (s) or 2 or more types.

  The toner such as the color toner of the present invention may contain a charge control agent in the toner as necessary. For example, the color toner of the present invention can contain a charge control agent in the toner as needed. For example, nigrosine, an azine dye containing an alkyl group having 2 to 16 carbon atoms (Japanese Patent Publication No. 42-1627), a basic dye (for example, CI Basic Yellow 2 (CI 41000), CI Basic Yellow 3, C.I.Basic Red 1 (C.I. 45160), C.I.Basic Red 9 (C.I. 42500), C.I.Basic Violet 1 (C.I. 42535), C I. Basic Violet 3 (C.I. 42555), C. I. Basic Violet 10 (C.I. 45170), C.I.Basic Violet 14 (C.I. 42510), C.I.Basic Blueet 1 (C.I. 42025), C.I.Basic Blue 3 (C.I.51005), C.I. ascii blue 5 (C.I. 42140), C.I.Basic Blue 7 (C.I.42595), C.I.Basic Blue 9 (C.I.522015), C.I.Basic Blue 24 (C. CI Basic Blue 25 (C.I.52025), C.I.Basic Blue 26 (C.I.44045), C.I.Basic Green 1 (C.I.42040), Lake pigments of these basic dyes, such as CI Basic Green 4 (CI 42000), CI Solvent Black 8 (CI 26150), benzoylmethyl hexadecyl ammonium chloride, decyltrimethyl chloride Quaternary ammonium salts, or dibutyl or dioctyl Polyamine resins such as dialkyl tin compounds, dialkyl tin borate compounds, guanidine derivatives, vinyl polymers containing amino groups, condensation polymers containing amino groups, Japanese Patent Publication No. 41-20153, Japanese Patent Publication No. 43-27596 A metal complex salt of a monoazo dye described in JP-B-44-6397 and JP-B-45-26478, salicylic acid described in JP-B-55-42752, JP-B-59-7385, Examples include dialkyl salicylic acid, naphthoic acid, dicarboxylic acid metal complexes such as Zn, Al, Co, Cr, and Fe, sulfonated copper phthalocyanine pigments, organic boron salts, fluorine-containing quaternary ammonium salts, calixarene compounds, and the like. . Naturally, color toners other than black should avoid the use of charge control agents that impair the target color, and white metal salts of salicylic acid derivatives are preferably used.

As for the external additive of the toner, transferability and durability are further improved by externally adding inorganic fine particles such as silica, titanium oxide, alumina, silicon carbide, silicon nitride, boron nitride and resin fine particles to the base toner particles. Yes. This effect can be obtained by covering the wax that lowers transferability and durability with these external additives and reducing the contact area due to the toner surface being covered with fine particles. The surface of these inorganic fine particles is preferably subjected to a hydrophobic treatment, and metal oxide fine particles such as silica and titanium oxide subjected to the hydrophobic treatment are preferably used. As the resin fine particles, polymethyl methacrylate or polystyrene fine particles having an average particle size of about 0.05 to 1 μm obtained by a soap-free emulsion polymerization method are suitably used. In addition, the combination of hydrophobized silica and hydrophobized titanium oxide increases the amount of hydrophobized titanium oxide externally added compared to the amount of hydrophobized silica externally charged. The toner can also be excellent in stability. In combination with the above-mentioned inorganic fine particles, silica having a specific surface area of 20 to 50 m ² / g and resin fine particles having an average particle diameter of 1/100 to 1/8 of the average particle diameter of the toner are conventionally used. The durability can be improved by externally adding an external additive having a particle size larger than that of the additive to the toner. This is because the metal oxide particles externally added to the toner tend to be embedded in the base toner particles in the process where the toner is mixed and stirred with the carrier in the developing device, charged, and used for development. This is because it is possible to prevent the metal oxide fine particles from being embedded by externally adding an external additive having a particle size larger than that of the oxide fine particles to the toner. The above-mentioned inorganic fine particles and resin fine particles are contained (internally added) in the toner, but the effect is reduced as compared with the case of external addition, but the effect of improving transferability and durability can be obtained and the pulverization property of the toner can be improved. Can do. In addition, since external addition and internal addition can be used together to suppress embedding of externally added fine particles, excellent transferability can be stably obtained and durability can be improved.

In addition, the following are mentioned as a typical example of the hydrophobization processing agent used here.
Dimethyldichlorosilane, trimethylchlorosilane, methyltrichlorosilane, allyldimethyldichlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, p-chloroethyltrichlorosilane, Chloromethyldimethylchlorosilane, chloromethyltrichlorosilane, p-chlorophenyltrichlorosilane, 3-chloropropyltrichlorosilane, 3-chloropropyltrimethoxysilane, vinyltriethoxysilane, vinylmethoxysilane, vinyl-tris (β-methoxyethoxy) ) Silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinyldichlorosilane, dimethylvinylchlorosilane, octyl Trichlorosilane, decyl-trichlorosilane, nonyl-trichlorosilane, (4-t-propylphenyl) -trichlorosilane, (4-t-butylphenyl) -trichlorosilane, diventyl-dichlorosilane, dihexyl-dichlorosilane, dioctyl-dichlorosilane, dinonyl -Dichlorosilane, didecyl-dichlorosilane, didodecyl-dichlorosilane, dihexadecyl-dichlorosilane, (4-t-butylphenyl) -octyl-dichlorosilane, dioctyl-dichlorosilane, didecenyl-dichlorosilane, dinonenyl-dichlorosilane, di-2-ethylhexyl-dichlorosilane, di- 3,3-dimethylbenthyl-dichlorosilane, trihexyl-chlorosilane, trioctyl-chlorosilane, tridecyl-chlorosilane Dioctyl-methyl-chlorosilane, octyl-dimethyl-chlorosilane, (4-t-propylphenyl) -diethyl-chlorosilane, octyltrimethoxysilane, hexamethyldisilazane, hexaethyldisilazane, diethyltetramethyldisilazane, hexaphenyldisilazane , Hexatolyl disilazane and the like.
In addition, titanate coupling agents and aluminum coupling agents can also be used. In addition, as an external additive for the purpose of improving cleaning properties, a lubricant such as a fatty acid metal salt or a fine particle of polyvinylidene fluoride can be used in combination.

  As the carrier core material used in the present invention, a carrier having an average particle size of 20 μm (average particle size) is used at least in order to prevent carrier adhesion (scattering) to the electrostatic latent image carrier. From the viewpoint of preventing image quality deterioration such as the prevention of streaks, it is preferable to use one having an average particle size of 100 μm at most. Specific materials may be appropriately selected according to the use and purpose of use of a carrier known in the art as a two-component carrier for electrophotography, such as ferrite, magnetite, iron, nickel, etc., and are not limited to examples.

  Conventionally known methods can be applied to the toner production method of the present invention. As a device for kneading the toner, a batch-type twin roll, a Banbury mixer, a continuous twin-screw extruder, for example, KTK manufactured by Kobe Steel, Ltd. Type twin screw extruder, Toshiba Machine's TEM type twin screw extruder, KCK's twin screw extruder, Ikekai Tekko's PCM type twin screw extruder, Kurimoto Iron Works' KEX type twin screw extruder, A single-screw kneader of a formula, for example, a co-kneader manufactured by Buss, is preferably used. As described above, the obtained melt-kneaded product is cooled and then pulverized. For example, the pulverization is roughly pulverized using a hammer mill, a funnel plex or the like, and further, a fine pulverizer using a jet stream or a mechanical pulverizer. A crusher or the like can be used. The pulverization is desirably performed so that the average particle diameter is 3 to 15 μm. Furthermore, it is preferable that the particle size of the pulverized product is adjusted to 5 to 20 μm by a wind classifier or the like. Subsequently, the external additive is externally added to the base toner, and the base toner and the external additive are mixed and stirred using a mixer, and the external additive is crushed and coated on the toner surface. At this time, it is important in terms of durability that external additives such as inorganic fine particles and resin fine particles are uniformly and firmly attached to the base toner.

The image forming apparatus of the present invention will be described below with reference to the drawings.
FIG. 1 shows an example of an image forming apparatus on which a container filled with the developer of the present invention is mounted. The developing unit (1) mounted in the main body of the image forming apparatus, and the developing unit FIG. 2 is a partial cross-sectional view showing a developer storage container (2) filled with the developer of the present invention to be replenished in (1) and a developer flow means (3) for connecting the two.

  In FIG. 1, a developing section (1) includes a developing housing (4) in which a developer container of the present invention containing a two-component developer (D) of the present invention is mixed. And a first and second agitating screws (5) and (6) for agitating the developer (D) as necessary, and a developing roller (7), the developing roller (7) It is arranged opposite to the latent image carrier photoconductor (8). The photoconductor (8) is rotationally driven in the direction indicated by the arrow, and an electrostatic latent image is formed on the surface thereof. In the drawing, reference numeral (126) denotes a cap fitted on the connecting member (124) with or without the filter (125). Around the photosensitive member (8), other well-known units such as a charging unit, an exposure unit, a transfer unit, a charge removing unit, and a cleaning unit (not shown) are arranged.

As the first and second agitating screws (5) and (6) rotate, the developer (D) in the developing housing (4) is agitated, and the toner is triboelectrically charged with opposite polarity to the carrier. . The developer (D) is supplied to the peripheral surface of the developing roller (7) that is rotationally driven in the direction of the arrow, and the supplied developer is carried on the peripheral surface of the developing roller (7). It is conveyed in the rotation direction by the rotation of 7). Next, the amount of the conveyed developer is regulated by the doctor blade (9), and the regulated developer is conveyed to the development area between the photosensitive member (8) and the developing roller (7), where The toner in the developer is electrostatically transferred to the electrostatic latent image on the surface of the photoreceptor, and the electrostatic latent image is visualized as a toner image.
Still another embodiment for carrying out the image forming method of the present invention by using another example of the image forming apparatus of the present invention (for example, the image forming apparatus shown in FIGS. 2 to 5) will be described with reference to FIG.
The image forming apparatus (100) of the example shown in FIG. 2 includes a photosensitive drum (10) as an electrostatic latent image carrier (hereinafter referred to as “photosensitive member 10”), a roller-shaped charging unit (20), and an exposure unit. (30), a developing means (40), an intermediate transfer member (50), a cleaning means (60) having a cleaning blade, and a static elimination lamp as a static elimination means (70).

  The intermediate transfer member (50) is an endless belt, and is designed to be movable in the direction of the arrow by three rollers (51) that are arranged on the inner side and stretch the belt. A part of the three rollers (51) also functions as a transfer bias roller capable of applying a predetermined transfer bias (primary transfer bias) to the intermediate transfer member (50). A cleaning means (90) having a cleaning blade is disposed in the vicinity of the intermediate transfer member (50), and a developed image (image-forming particle image) is transferred to a transfer paper (95) as a final transfer material. Transfer rollers as transfer means (80) to which a transfer bias for (secondary transfer) can be applied are arranged to face each other. Around the intermediate transfer member (50), there is a corona charger (58) for applying a charge to the image-forming particle image on the intermediate transfer member (50) in the rotational direction of the intermediate transfer member (50). It is arranged between the contact portion between the photoconductor (10) and the intermediate transfer member (50) and the contact portion between the intermediate transfer member (50) and the transfer paper (95).

  The developing means (40) includes a developing belt (41) as a developer carrier, a black developing means (unit) (45K) provided around the developing belt (41), a yellow developing means (unit) (45Y), It is composed of a magenta developing means (unit) (45M) and a cyan developing means (unit) (45C). The black developing means (45K) includes a developer accommodating portion (42K), a developer supply roller (43K), and a developing roller (44K). The yellow developing means (45Y) is provided with a developer accommodating portion ( 42Y), a developer supply roller (43Y), and a development roller (44Y). The magenta developing means (45M) includes a developer accommodating portion (42M), a developer supply roller (43M), and a development roller (44M). The cyan developing means (45C) includes a developer container (42C), a developer supply roller (43C), and a developing roller 44C. Further, the developing belt 41 is an endless belt, is rotatably stretched around a plurality of belt rollers, and a part thereof is in contact with the photoreceptor (10).

  In the image forming apparatus (100) shown in FIG. 2, for example, the charging means (20) charges the photosensitive drum 10 uniformly. The exposure means (30) exposes the photosensitive drum (10) imagewise to form an electrostatic latent image. The electrostatic latent image formed on the photosensitive drum (10) is developed by supplying image forming particles from the developing means (40) to form a visible image (image forming particle image). The visible image (image-forming particle image) is transferred (primary transfer) onto the intermediate transfer body (50) by the voltage applied from the roller (51), and further transferred onto the transfer paper (95) (secondary transfer). ) As a result, a transfer image is formed on the transfer paper (95). The residual image forming particles on the photoreceptor (10) are removed by the cleaning means (60), and the charge on the photoreceptor (10) is once removed by the charge eliminating means (charge eliminating lamp) (70).

  Another mode for carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to FIG. The image forming apparatus (100) shown in FIG. 3 does not include the developing belt (41) in the image forming apparatus (100) shown in FIG. 2, and a black developing means (developing unit) (developing unit) ( 45K), the yellow developing means (developing unit) (45Y), the magenta developing means (developing unit) (45M) and the cyan developing means (developing unit) (45C) are arranged directly opposite to each other, as shown in FIG. The image forming apparatus (100) shown in FIG. In FIG. 3, the same components as those in FIG. 2 are denoted by the same reference numerals.

Still another embodiment for carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to FIG. The tandem image forming apparatus (120) shown in FIG. 4 is a tandem color image forming apparatus. The tandem image forming apparatus (120) includes a copying apparatus main body (150), a paper feed table (200), a scanner (300), and an automatic document feeder (ADF) (400). The copying machine main body (150) is provided with an endless belt-like intermediate transfer member (50) at the center. The intermediate transfer member (50) is stretched around the support rollers (14), (15) and (16), and can rotate clockwise in FIG. An intermediate transfer body cleaning device (17) for removing residual image forming particles on the intermediate transfer body (50) is disposed in the vicinity of the support roller (15). The intermediate transfer member (50) stretched between the support roller (14) and the support roller (15) has four image forming units (18) of yellow, cyan, magenta, and black along the conveyance direction. A tandem developing means (120) arranged opposite to each other is arranged. An exposure means (21) is disposed in the vicinity of the tandem developing means (120). A secondary transfer unit (22) is disposed on the side of the intermediate transfer member (50) opposite to the side on which the tandem type developing unit (120) is disposed. In the secondary transfer means (22), a secondary transfer belt (24), which is an endless belt, is stretched between a pair of rollers (23), and a transfer sheet conveyed on the secondary transfer belt (24); The intermediate transfer member (50) can contact each other. A fixing means (25) is disposed in the vicinity of the secondary transfer means (22). The fixing means (25) includes a fixing belt (26) that is an endless belt, and a pressure roller (27) that is pressed against the fixing belt (26).
In the tandem image forming apparatus (120), a sheet reversal is performed in the vicinity of the secondary transfer unit (22) and the fixing unit (25) for reversing the transfer paper in order to form an image on both sides of the transfer paper. A device (28) is arranged.

  Next, full color image formation (color copying) using the tandem developing means (120) will be described. That is, first, a document is set on the document table (130) of the automatic document feeder (ADF) (400) or the automatic document feeder (400) is opened and the contact glass (32) of the scanner (300) is opened. A document is set on the document and the automatic document feeder (400) is closed.

  When a start switch (not shown) is pressed, when a document is set on the automatic document feeder (400), the document is transported and moved onto the contact glass (32). ) Immediately after the document is set on the scanner (300), the first traveling body (33) and the second traveling body (34) travel. At this time, light from the light source is irradiated by the first traveling body (33) and reflected light from the document surface is reflected by the mirror in the second traveling body (34), and is read through the imaging lens (35). The color original (color image) is read at (36), and is read as black, yellow, magenta and cyan image information.

  Each image information of black, yellow, magenta and cyan is stored in each image forming means (18) (black image forming means, yellow image forming means, magenta image forming means and cyan) in the tandem developing means (120). Image forming means), and image forming particle images of black, yellow, magenta and cyan are formed in each image forming means. That is, each image forming means (18) (black image forming means, yellow image forming means, magenta image forming means and cyan image forming means) in the tandem developing means (120) is partially enlarged in FIG. As shown in FIG. 5, which is a schematic diagram, the photoreceptor (10) (the photoreceptor for black (10K), the photoreceptor for yellow (10Y), the photoreceptor for magenta (10M), and the photoreceptor for cyan (10C), respectively. ), A charging means (59) for uniformly charging the photoconductor, and exposing the photoconductor to each color image corresponding image based on each color image information (L in FIG. 5). Exposure means for forming an electrostatic latent image corresponding to each color image on the surface, and each color developer (black developer, yellow developer, magenta developer and cyan developer) of the present invention on the electrostatic latent image. Use and develop each A developing means (61) for forming a toner image with a developer, a transfer charger (62) for transferring the developed toner image onto the intermediate transfer body (50), and a photoreceptor cleaning means (63). And a static eliminator (64), and each monochrome image (black image, yellow image, magenta image, and cyan image) can be formed based on the image information of each color. The black image, the yellow image, the magenta image, and the cyan image formed in this way are transferred onto the intermediate transfer member (50) that is rotationally moved by the support rollers (14), (15), and (16) in FIG. The black image formed on the black photoconductor (10K), the yellow image formed on the yellow photoconductor (10Y), the magenta image formed on the magenta photoconductor (10M), and the cyan photoconductor, respectively. The cyan image formed on the body (10C) is sequentially transferred (primary transfer). Then, the black image, the yellow image, the magenta image, and the cyan image are superimposed on the intermediate transfer member (50) to form a composite color image (color transfer image).

On the other hand, in the paper feed table (200), one of the paper feed rollers (142) is selectively rotated so that the sheet (recording paper) is fed from one of the paper feed cassettes (144) provided in the paper bank (143). ), Separated one by one by the separation roller (145), sent to the paper feed path (146), and conveyed by the conveyance roller (147) to the paper feed path (148) in the copier body (150). Guide and stop against the registration roller (49). Alternatively, the sheet feed roller (142) is rotated to feed out the sheets (recording paper) on the manual feed tray (54), separated one by one by the separation roller (52), and put into the manual feed path (53). Stop against the registration roller (49). The registration roller (49) is generally used while being grounded, but may be used in a state where a bias is applied to remove paper dust from the sheet.
Then, the registration roller (49) is rotated in synchronism with the synthesized color image (color transfer image) in which the respective toners are synthesized on the intermediate transfer member (50), and the intermediate transfer member (50) and the secondary transfer means ( 22), a sheet (recording paper) is sent to the sheet (recording paper), and the composite color image (color transfer image) is transferred (secondary transfer) onto the sheet (recording paper) by the secondary transfer means (22). A color image is transferred and formed on the sheet (recording paper). The residual toner on the intermediate transfer member (50) after the image transfer is cleaned by the intermediate transfer member cleaning device (17).

  The sheet (recording paper) on which the color image has been transferred is transported by the secondary transfer means (22) and sent to the fixing means (25). The fixing means (25) generates heat and pressure. The composite color image (color transfer image) is fixed on the sheet (recording paper). Thereafter, the sheet (recording paper) is switched by the switching claw (55) and discharged by the discharge roller (56) and stacked on the discharge tray (57), or switched by the switching claw (55) and the sheet is reversed. The image is reversed by the device (28) and guided again to the transfer position, and an image is recorded also on the back surface. Then, the image is discharged by the discharge roller (56) and stacked on the discharge tray (57).

  FIG. 6 specifically shows a schematic diagram of an image forming apparatus equipped with the process cartridge of the present invention.

The process cartridge of the present invention uses the developer of the present invention, and a photoreceptor and developing means,
And a process cartridge that integrally supports at least one unit selected from a charging unit and a cleaning unit and is detachable from the main body of the image forming apparatus.
FIG. 6 shows a schematic configuration of an image forming apparatus having the process cartridge of the present invention.
In the figure, (101) indicates the entire process cartridge, (10) indicates a photosensitive member, (20) indicates a charging unit, (40) indicates a developing unit, and (60) indicates a cleaning unit.
In the present invention, a plurality of components such as the above-described photoreceptor (11), charging means (12), developing means (13), and cleaning means (14) are integrally combined as a process cartridge. The process cartridge is configured to be detachable from an image forming apparatus main body such as a copying machine or a printer.

  In the image forming apparatus having the process cartridge of the present invention, the photosensitive member is rotationally driven at a predetermined peripheral speed. In the rotation process, the photosensitive member is uniformly charged with a positive or negative predetermined potential on its peripheral surface by the charging unit, and then receives image exposure light from an image exposing unit such as slit exposure or laser beam scanning exposure. An electrostatic latent image is sequentially formed on the peripheral surface of the body, and the formed electrostatic latent image is then developed with toner by a developing unit, and the developed toner image is transferred between the photosensitive member and the transfer unit from the paper feeding unit. Then, the image is sequentially transferred to the transfer material fed in synchronization with the rotation of the photosensitive member by the transfer means. The transfer material that has received the image transfer is separated from the surface of the photosensitive member, introduced into the image fixing means, and fixed on the image, and printed out as a copy (copy). The surface of the photoconductor after the image transfer is cleaned by removing toner remaining after transfer by a cleaning unit, and after being further neutralized, it is repeatedly used for image formation.

Next, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited to these. Parts are based on weight.
( Reference Example 1)
・ Acrylic resin solution (solid content 50 wt%) 42.0 parts ・ Guanamine solution (solid content 70 wt%) 13.0 parts ・ Alumina particles [0.3 μm, specific resistance 10 ^ 14 (Ω · cm)] 7.6 parts -60 parts of toluene-60 parts of butyl cellosolve were dispersed with a homomixer for 10 minutes to obtain an acrylic resin coating film forming solution containing alumina particles. An average particle diameter of 35 μm sintered ferrite powder was used as the core material, and the above coating film forming solution was applied to the surface of the core material by a Spira coater (manufactured by Okada Seiko Co., Ltd.) so as to have a film thickness of 0.15 μm. The obtained carrier was baked by standing in an electric furnace at 150 ° C. for 1 hour. After cooling, the ferrite powder bulk was pulverized using a sieve having an aperture of 63 μm to obtain [Carrier 1] having alumina of 20 wt% of the coating film composition component and D / h of 2.0. The measurement of the binder resin film thickness was performed by observing the cross section of the carrier with a transmission electron microscope so that the coating film covering the carrier surface could be observed.
On the other hand, toner
-Binder resin (B): 100 parts of styrene acrylic resin-Release agent: 5 parts of synthetic ester wax-Charge control agent: E-84 [manufactured by Orient Chemical Co., Ltd.] 2 parts-Colorant: 3 parts of carbon black Among them, the colorant, the binder resin (B) and pure water were mixed at a ratio of 1: 1: 0.5 and kneaded by two rolls. Kneading was performed at 70 ° C., and then the roll temperature was raised to 120 ° C. to evaporate water and prepare a master batch in advance. Using the master batch obtained in this way, weigh the materials so that they are the same as the above recipe, mix with a Henschel mixer, melt knead for 40 minutes at 120 ° C. with two rolls, cool, and then coarsely pulverize with a hammer mill Thereafter, fine powder obtained by fine pulverization with an air jet pulverizer was classified to prepare toner base particles having a weight average particle diameter of 5 μm. Furthermore, 0.5% of hydrophobic silica (H2000, manufactured by Clariant Japan) was added and mixed with a Henschel mixer to obtain [Toner 1].
7 parts of [Toner 1] and 93 parts of [Carrier 1] thus obtained were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and evaluated for glossiness, offset property and durability (charge reduction amount, resistance change amount). did. The results are shown in Table 1.
The evaluation methods and conditions in the examples are shown below.

<Glossiness>
Replace the fixing roller with a PFA tube-coated roller, and adjust it so that 1.0 ± 0.1 mg / cm ² of toner is developed using a modified Ricoh Color Copier Pretail 650 machine with the silicone oil applicator removed. The glossiness of the solid image sample when the fixing roller surface temperature was 160 ° C. was measured under the condition of an incident angle of 60 ° using a gloss meter manufactured by Nippon Denshoku Industries Co., Ltd. The transfer paper used was Ricoh full color PPC paper type 6000 <70W. As for the glossiness, the higher the value, the more glossy, and the evaluation criteria differ between monochrome and color. First, with regard to monochrome, in general, monochrome is often used for copying or printing with a small image area such as characters, and there is a tendency that low gloss is preferred. On the other hand, high gloss is difficult to read characters, etc. Tend not to like. Therefore, in the case of monochrome, the glossiness is preferably 10% or less. On the other hand, color is often used for copying or printing of a large image area such as a photograph, and a high gloss tends to be preferred. On the contrary, a low gloss is not preferred due to lack of clarity. Tend. Therefore, it is necessary to obtain a clear image with excellent color reproducibility, and a glossiness of about 10% or more is required. The fixing roller is a 2 mm thick silicon rubber covered with a 25 μm PFA tube, the fixing pressure is 80 kg, the nip width is 8 mm, and the nip shape is recessed toward the fixing roller. The heater output of the fixing roller was 650 W, and the heater output of the pressure roller was 400 W.

<Offset>
Using a modified Ricoh Color Copier Pretail 650 machine used for the evaluation of glossiness, the temperature of the fixing roller was changed by 5 ° C., and the temperature at which offset started to occur was measured. The fixing roller was evaluated under the condition that no oil was applied, and the transfer paper was Ricoh Full Color PPC paper type 6000 <70 W. The evaluation results were expressed as follows.
◎: No offset is generated up to very high temperature (240 ° C) and excellent offset resistance ○: No offset occurs up to high temperature (210 ° C) and excellent in offset resistance △: Offset resistance is insufficient If a small amount of silicon oil (0.5 to 1 mg / A4 size) is applied, the offset resistance is satisfied.
X: Offset occurs from a low temperature (150 ° C.) and is inferior in offset resistance even when a small amount of silicon oil is applied.

<Durability>
It was set in a modified machine of a commercially available digital full-color copying machine (imageColor 2800 manufactured by Ricoh Co., Ltd.), and a running evaluation of 300,000 sheets in a single color was performed. Table 1 shows the results of obtaining the charge reduction amount and resistance reduction amount of the carrier after the running.
The amount of charge reduction referred to here is a sample obtained by mixing and charging the toner at a ratio of 5 wt% with respect to 95 wt% of the initial carrier by a general blow-off method [manufactured by Toshiba Chemical Co., Ltd .: TB-200]. The amount obtained by subtracting the amount of charge (Q2) measured by the same method as the above method from the amount of charge (Q1) measured in this manner, and the carrier from which the toner in the developer after running was removed by the blow-off device. That is, the target value is within 5.0 (μc / g). Further, since the cause of the decrease in the charge amount is the toner spent on the carrier surface, the decrease in the charge amount can be suppressed by reducing the toner spent.
The amount of change in resistance here means that the initial carrier is put between resistance measurement parallel electrodes: electrodes with a gap of 2 mm, the resistance value after 30 sec is applied by DC250V, and the value measured with a high resist meter is converted into volume resistivity. The amount obtained by subtracting the value (R2) measured by the same method as the resistance measuring method from the value (R1) obtained by removing the toner in the developer after running by the blow-off device. In other words, the target value is within 2.0 [Log (Ω · cm)] in absolute value. In addition, the cause of the resistance change is scraping of the binder resin (A) film of the carrier, spent toner component, large particle detachment in the carrier coating film, etc. Can be suppressed.

( Reference Example 2)
In Reference Example 1, the same [Toner 2] was prepared except that the binder resin (B) was replaced with a polyester resin [Mw; 60000, acid value: 15 mg KOH / g, glass transition point: 65 ° C.].
7 parts of [Toner 2] thus obtained and 93 parts of [Carrier 1] used in Reference Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%. The results of the same evaluation as in Reference Example 1 were performed. Table 1 shows.

(Example 1 )
In Reference Example 2, the same [Toner 3] was prepared except that the release agent was replaced with a synthetic ester wax having the following long-chain branched structure.

こうして得た［トナー３］７部と参考例１で用いた［キャリア１］９３部とを混合攪拌し、トナー濃度７ｗｔ％の現像剤を得、参考例１と同様の評価を行なった結果を表１に示す。

7 parts of [Toner 3] obtained in this way and 93 parts of [Carrier 1] used in Reference Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%. The results of the same evaluation as in Reference Example 1 were performed. Table 1 shows.

(Example 2 )
・ Acrylic resin solution (solid content 50 wt%) 21.0 parts ・ Guanamine solution (solid content 70 wt%) 6.4 parts ・ Alumina particles [0.3 μm, specific resistance 10 ^ 14 (Ω · cm)] 7.6 parts・ Silicon resin solution [Solid content 23 wt% (SR2410: Toray Dow Corning Silicone)]
65.0 parts Aminosilane [Solid content 100 wt% (SH6020: manufactured by Toray Dow Corning Silicone)]
0.3 parts, 60 parts of toluene, 60 parts of butyl cellosolve are dispersed with a homomixer for 10 minutes to obtain a blend coating film forming solution of acrylic resin and silicon resin containing alumina particles, and carrierized in the same manner as in Reference Example 1. Then, [Carrier 2] was obtained in which alumina was 20 wt% of the coating film composition component and D / h was 2.0.
93 parts of [Carrier 2] thus obtained and 5 parts of [Toner 3] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 3 )
・ Acrylic resin solution (solid content 50 wt%) 21.0 parts ・ Guanamine solution (solid content 70 wt%) 6.4 parts ・ Alumina particles [0.3 μm, specific resistance 10 ^ 14 (Ω · cm)] 7.6 parts -60 parts of toluene-60 parts of butyl cellosolve were dispersed with a homomixer for 10 minutes to obtain an acrylic resin coating film forming solution containing alumina particles. After using an average particle diameter of 35 μm calcined ferrite powder as a core material and applying the above coating film forming solution on the surface of the core material with a Spira coater (Okada Seiko Co., Ltd.) to a film thickness of 0.08 μm, and drying,
・ Silicon resin solution [Solid content 23 wt% (SR2410: Toray Dow Corning Silicone)]
65.0 parts Aminosilane [Solid content 100 wt% (SH6020: manufactured by Toray Dow Corning Silicone)]
0.3 parts, 60 parts of toluene, 60 parts of butyl cellosolve are dispersed in a container with an agitator for 5 minutes to obtain a silicon resin coating film forming solution, and this solution is applied to the carrier surface on which the acrylic resin coating layer is formed. It was applied and dried so that the total film thickness of the acrylic resin layer and the silicon resin layer was 0.15 μm. The obtained carrier was baked by standing in an electric furnace at 150 ° C. for 1 hour. After cooling, the ferrite powder bulk was crushed using a sieve having an aperture of 63 μm, and alumina was 20 wt% of the coating film composition component and D / h was 2.0 [Carrier 3]. As a result, the coating film forms a two-layer structure with the acrylic resin in the lower layer and the silicon resin in the upper layer. 93 parts of [Carrier 3] thus obtained and 7 parts of [Toner 3] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 4 )
・ Acrylic resin solution (solid content 50 wt%) 21.0 parts ・ Guanamine solution (solid content 70 wt%) 6.4 parts ・ Alumina particles [0.3 μm, specific resistance 10 ^ 14 (Ω · cm)] 121.0 parts・ Silicon resin solution [Solid content 23 wt% (SR2410: Toray Dow Corning Silicone)]
65.0 parts Aminosilane [Solid content 100 wt% (SH6020: manufactured by Toray Dow Corning Silicone)]
0.3 parts, 60 parts of toluene, 60 parts of butyl cellosolve are dispersed with a homomixer for 10 minutes to obtain a blend coating film forming solution of acrylic resin and silicon resin containing alumina particles, and carrierized in the same manner as in Reference Example 1. did. As a result, [Carrier 4] having alumina of 80 wt% of the coating film composition component and D / h of 2.0 was obtained. 93 parts of [Carrier 4] thus obtained and 7 parts of [Toner 3] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 5 )
In Example 4 , [Carrier 5] was produced in the same manner except that 121.0 parts of titanium oxide particles [0.3 μm, specific resistance 10 ^ 7 (Ω · cm)] were used instead of alumina. 93 parts of [Carrier 5] thus obtained and 7 parts of [Toner 3] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 6 )
In Example 4 , [Carrier 6] was produced in the same manner except that 121.0 parts of zinc oxide particles [0.3 μm, specific resistance 10 ^ 7 (Ω · cm)] were used instead of alumina. 93 parts of [Carrier 6] thus obtained and 7 parts of [Toner 3] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 7 )
・ Acrylic resin solution (solid content 50 wt%) 2.2 parts ・ Guanamine solution (solid content 70 wt%) 0.7 parts ・ Alumina particles [0.3 μm, specific resistance 10 ^ 14 (Ω · cm)] 7.6 parts・ Silicon resin solution [Solid content 23 wt% (SR2410: Toray Dow Corning Silicone)]
126.0 parts Aminosilane [Solid content 100 wt% (SH6020: manufactured by Toray Dow Corning Silicone)]
0.63 parts, 60 parts of toluene, 60 parts of butyl cellosolve are dispersed with a homomixer for 10 minutes to obtain a blend coating film forming solution of acrylic resin and silicon resin containing alumina particles, and carrierized in the same manner as in Reference Example 1. [Carrier 7] having an acrylic resin ratio of 5 wt% was produced. 93 parts of [Carrier 7] thus obtained and 7 parts of [Toner 3] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 8 )
[Example 8] [Carrier 8] was produced in the same manner as in Example 4 except that D / h was 15 by using alumina having a particle diameter of 2.3 µm. 93 parts of [Carrier 8] thus obtained and 7 parts of [Toner 3] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 9 )
[Toner 4] was obtained in the same manner as in Example 4 , except that the colorant of the toner was changed to [Pigment Yellow 180, primary particle diameter of pigment: 90 nm] by 4 parts. 7 parts of [Toner 4] thus obtained and 93 parts of [Carrier 4] used in Example 4 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 10 )
[Toner 5] was obtained in the same manner as in Example 4 except that the colorant of the toner was changed to [Pigment Violet 19, pigment primary particle size; 100 nm] by 5 parts. 7 parts of [Toner 5] thus obtained and 93 parts of [Carrier 4] used in Example 4 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Example 11 )
[Toner 6] was obtained in the same manner as in Example 4 except that the colorant of the toner was changed to [Pigment Blue 15-3, pigment primary particle size; 60 nm] by 2 parts. 7 parts of [Toner 6] thus obtained and 93 parts of [Carrier 4] used in Example 4 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Comparative Example 1)
・ Silicon resin solution [Solid content 23 wt% (SR2410: Toray Dow Corning Silicone)]
132.2 parts aminosilane [solid content 100 wt% (SH6020: manufactured by Toray Dow Corning Silicone)]
0.66 parts, alumina particles [0.3 μm, specific resistance 10 ^ 14 (Ω · cm)] 121.0 parts, toluene 300 parts, butyl cellosolve 300 parts are dispersed with a homomixer for 10 minutes, and silicon containing alumina particles A resin coating film forming solution was obtained, and [Carrier 9] was produced in the same manner as in Reference Example 1. 93 parts of [Carrier 9] thus obtained and 7 parts of [Toner 3] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Reference Example 1 was performed. Is shown in Table 1.

(Comparative Example 2)
In Reference Example 1, D / h was 0.8 by using alumina having a particle size of 0.12 μm, and the other [Carrier 10] was manufactured in the same manner. 93 parts of [Carrier 10] thus obtained and [Toner 3] 7 used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%. The results of evaluation similar to Reference Example 1 were performed. Table 1 shows.

(Comparative Example 3)
[Toner 7] was obtained in the same manner as in Example 1 except that the toner release agent was replaced with montan wax. 7 parts of [Toner 7] thus obtained and 93 parts of [Carrier 1] used in Example 1 were mixed and stirred to obtain a developer having a toner concentration of 7 wt%, and the same evaluation as in Example 1 was performed. Is shown in Table 1.

From Table 1 above, in Reference Example 1 in which the carrier coating resin is an acrylic resin, the coating resin layer contains particles, and the toner contains a synthetic ester wax, glossiness, offset property, and durability (charge reduction amount, resistance) Good results were obtained within the range of the target value for all of the (variation).
Further, the carrier is the same as in Reference Example 1, and the toner is glossiness, offset property, and durability (charge reduction amount, resistance change) in Reference Example 2 in which the binder resin (B) in Reference Example 1 is replaced with a polyester resin. All of (quantity) were within the target value range and good results were obtained.
Further, the carrier was the same as in Reference Example 1, and the toner was replaced with a synthetic ester wax having a long-chain branched structure as the release agent in Reference Example 2. In Example 1 , glossiness, offset property, durability (charge reduction amount) , Resistance change amount) was within the target value range, and good results were obtained . In particular, better results than those of Reference Examples 1 and 2 were obtained with respect to offset property and durability .
Further, the toner is the same as in Example 1, and in Example 2 in which the coating resin of the carrier includes a silicone resin in addition to the acrylic resin, glossiness, offset property, and durability (charge reduction amount, resistance change amount) are all included. Good results were obtained within the range of the target value, and particularly better results than those of Reference Examples 1 and 2 were obtained with respect to offset property and durability .
Further, the toner is the same as in Example 1, and also in Example 3 in which the carrier coating film has a two-layer structure of acrylic resin and alumina particles in the lower layer and silicon resin in the upper layer, glossiness, offset property, durability ( Good results within the range of the target values were obtained for all of the amount of charge reduction and resistance change, and in particular, better results than those of Reference Examples 1 and 2 were obtained with respect to offset property and durability .
Furthermore, also in Example 4 where the alumina amount is 80 wt% in Example 2 , all the glossiness, offset property, and durability (charge reduction amount, resistance change amount) are within the target value range and good results are obtained. In particular, better results than those of Reference Examples 1 and 2 were obtained with respect to offset property and durability .
Further, in Example 4, also in Example 5 in which titanium oxide is used instead of alumina, gloss, offset properties, durability (charge decrease, change in resistance) and good in the range of the target value at all The results were obtained, and in particular, better results than those of Reference Examples 1 and 2 were obtained with respect to offset property and durability .
Further, in Example 4, also in Example 6 using zinc oxide instead of alumina, gloss, offset properties, durability (charge decrease, change in resistance) and good in the range of the target value at all The results were obtained, and in particular, better results than those of Reference Examples 1 and 2 were obtained with respect to offset property and durability .
Further, the toner is the same as in Example 1 , but also in Example 7 where the acrylic resin content of the carrier coating resin is 5 wt%, the glossiness, offset property, and durability (charge reduction amount, resistance change amount) are similar. In all cases, good results were obtained within the range of the target value, and in particular, better results than those of Reference Examples 1 and 2 were obtained with respect to offset property .
Furthermore, also in Example 8 where the difference from Example 4 is the alumina particle diameter and D / h is 15, the target values are all in terms of glossiness, offset property, and durability (charge reduction amount, resistance change amount). Within the range, good results were obtained, and in particular, the offset properties were better than those of Reference Examples 1 and 2 .
Further, the carrier is the same as in Example 4 , but also in Example 9 where the toner colorant is [Pigment Yellow 180, pigment primary particle size; 90 nm], 4 parts, glossiness, offset property, durability (charging) In all of the reduction amount and the resistance change amount, good results were obtained within the range of the target values, and in particular, better results than those of Reference Examples 1 and 2 were obtained with respect to offset property and durability .
Further, the carrier is the same as in Example 4 , but also in Example 10 in which the toner colorant is [PigmentViolet19, pigment primary particle size; 100 nm] of 5 parts, glossiness, offset property, durability (charging) In all of the reduction amount and the resistance change amount, good results were obtained within the range of the target values, and in particular, better results than those of Reference Examples 1 and 2 were obtained with respect to offset property and durability .
Further, the carrier is the same as in Example 4 , but also in Example 11 where the toner colorant is [Pigment Blue 15-3, pigment primary particle size; In all of the (charge reduction amount, resistance change amount), good results were obtained within the range of target values, and in particular, better results than Reference Examples 1 and 2 were obtained with respect to offset property and durability .
On the other hand, Comparative Example 1 similar to Example 4 except that the coating resin of the carrier is all silicon resin, the alumina desorption is severe due to the low retention of alumina by the silicon resin, and the charge amount and resistance are low. The fluctuation was significantly different from the target value, and the results could not be used practically.
Further, in Example 4 where the alumina particle size was changed to 0.12 μm and D / h was 0.8, the variation in charge amount and resistance markedly deviated from the target values and could not be used practically. became.
Further, in Comparative Example 3 similar to Reference Example 1 except that the toner release agent is montan wax, the variation in charge amount and resistance was remarkably high, and the image deteriorated to a level that could not be used practically at the time of 50,000 sheets. , Stopped running.

FIG. 2 is a diagram illustrating a developer container filled with the electrophotographic developer of the present invention and an example of an image forming apparatus equipped with the container. It is the schematic which shows another example of the image forming apparatus which enforces the image forming method of this invention. It is the schematic which shows the further another example of the image forming apparatus which enforces the image forming method of this invention. It is the schematic which shows an example of the further another image forming apparatus (tandem type color image forming apparatus) for enforcing the image forming method of this invention. FIG. 5 is a partially enlarged schematic view of the image forming apparatus shown in FIG. 4. It is the schematic of the process cartridge of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Developing part 2 Developer storage container 3 Developer delivery means 4 Developing housing 5 Stir screw 6 Stir screw 7 Developing roller 8 Photoconductor 9 Doctor blade 10
10K black photoconductor 10Y yellow photoconductor 10M magenta photoconductor 10C cyan photoconductor 14 support roller 15 support roller 16 support roller 17 intermediate transfer cleaning device 18 image forming means 20 roller charging means 21 exposure means 22 secondary transfer means 23 Roller 24 Secondary transfer belt 25 Fixing means 26 Fixing belt 27 Pressure belt 28 Sheet reversing device 30 Exposure means 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading sensor 40 Developing means 41 Developing belt 42K developer container 42Y developer container 42M developer container 42C developer container 43K developer supply roller 43Y developer supply roller 43M developer supply roller 43C developer supply roller 44K developer roller 44Y developer roller 44M Developing roller 44C Developing roller 45K Black developing means (developing unit)
45Y yellow development means (development unit)
45M Magenta development means (development unit)
45C Cyan development means (development unit)
49 Registration roller 50 Intermediate transfer member 51 Roller 52 Separation roller 53 Manual feed path 54 Manual feed tray 55 Switching claw 56 Discharge roller 57 Discharge tray 58 Corona charger 59 Charging means 60 Cleaning means 61 Developing means 62 Transfer charger 63 Photoconductor cleaning Means 64 Static eliminator 70 Static elimination means (static elimination lamp)
80 Transfer roller 90 Cleaning means 95 Transfer paper 100 Image forming apparatus 101 Process cartridge 110 Belt type fixing device 120 Tandem type developing means 124 Connection member 125 Filter 126 Cap 130 Document table 142 Paper feed roller 143 Paper bank 144 Paper feed cassette 145 Separating roller 146 Feeding path 147 Conveying roller 148 Feeding path 150 Copier main body 200 Feeding table 300 Scanner 400 Automatic document feeder (ADF)

Claims (13)

A carrier having a carrier coating layer comprising at least a binder resin (A) and particles on the surface of the core, wherein the binder resin (A) contains at least an acrylic resin, and the particle diameter (D) of the particles and the carrier A toner comprising a carrier having a coating resin film thickness (h) of 1 <[D / h] <10, at least a binder resin (B), a colorant, and a synthetic ester wax represented by the following formula (1) A developer for developing an electrostatic charge image, comprising:

2. The developer for developing an electrostatic charge image according to claim 1, wherein the binder resin (A) of the carrier coating layer contains at least an acrylic resin and a silicon resin. The electrostatic charge image according to claim 1 or 2, wherein the binder resin (A) of the carrier coating layer comprises an acrylic resin and a silicon resin, and the two types of resins have a layer structure. Developer for development. The developer for developing an electrostatic charge image according to any one of claims 1 to 3, wherein the total content of the particles in the carrier coating layer is 40 to 95 wt% of the composition component of the coating layer. 5. The electrostatic charge image according to claim 4, wherein the particles contained in the carrier coating layer are one or more of alumina, titanium oxide, zinc oxide, or those obtained by subjecting them to surface treatment. Developer for development. 6. The developer for developing an electrostatic charge image according to claim 1, wherein the magnetic moment of the carrier at 1 KOe is 40 to 90 Am ² / kg. The weight average particle size of the carrier is 20 to 65 µm, and the content of carrier particles having a particle size of 9 µm or less is 3.0 wt% or less. A developer for developing electrostatic images. The developer for electrostatic image development according to any one of claims 1 to 7, wherein the binder resin (B) is a polyester resin. The toner is the electrostatic image developing color developer according to any one of claims 1 to 8, characterized in that a full color toner. Container, characterized in that accommodating the electrostatic latent image developer according to any one of claims 1 to 9. Image forming method which comprises using an electrostatic latent image developer according to any one of claims 1 to 9. It has at least a photosensitive member, a charging unit, an exposure unit, a developing unit, and a cleaning unit, and the developing unit uses the developer according to any one of claims 1 to 9. Image forming apparatus. A process cartridge that supports at least one unit selected from a photosensitive member as an image carrying unit, a charging unit, and a cleaning unit integrally with a developing unit and is detachable from an image forming apparatus main body. a process cartridge, wherein the agent holds, developer is the developer according to any one of claims 1 to 9.

Images