JP4239389B2 - Image forming method and image forming apparatus using cleaning device - Google Patents

Description

【０１８９】
表１より明らかなように、金属薄板部材とクリーニングブレードの自由長部が自由端になっている本発明の場合は、常温常湿（２０℃、５０％）、低温低湿（１０℃、２０％）、高温高湿（３０℃、８０％）のどの環境においてもブレードめくれやトナーすり抜け等の評価項目の全てに対し、良好なクリーニング特性を示しているのに対し、前記自由長部が自由端となっていない本発明外の場合は常温常湿条件下では良好なクリーニング特性を示しているが、低温低湿下、或いは高温高湿においてはブレードめくれやトナーすり抜け等が発生しやすいことが見出される。
【０１９０】
【発明の効果】
前記実施例からも明らかなように、本発明の条件で金属薄板部材を張り合わせたクリーニングブレードを有するクリーニング装置を用いることにより有機感光体上の残留トナーをブレードめくれやトナーすり抜けの発生もなく、効果的にクリーニングすることができる。又、本発明は該クリーニング装置を用いた画像形成方法、画像形成装置を提供することができる。
【図面の簡単な説明】
【図１】本発明の画像形成装置の全体の構成を示す概要構成図である。
【図２】本発明のクリーニングブレードを用いたクリーニング装置の構成図である。
【図３】攪拌翼の構成が一段の反応装置を示す説明図である。
【図４】好ましく使用することのできる攪拌翼を備えた反応装置の一例を示す斜視図である。
【図５】図４に示した反応装置の断面図である。
【図６】好ましく使用することのできる攪拌翼を備えた反応装置の具体例を示す斜視図である。
【図７】好ましく使用することのできる攪拌翼を備えた反応装置の具体例を示す斜視図である。
【図８】好ましく使用することのできる攪拌翼を備えた反応装置の具体例を示す斜視図である。
【図９】好ましく使用することのできる攪拌翼を備えた反応装置の具体例を示す斜視図である。
【図１０】好ましく使用することのできる攪拌翼を備えた反応装置の具体例を示す斜視図である。
【図１１】層流を形成させる場合に使用される反応装置の一例を示す斜視図である。
【図１２】攪拌翼の形状の具体例を示す概略図である。
【図１３】（ａ）は、角のないトナー粒子の投影像を示す説明図であり、（ｂ）および（ｃ）は、それぞれ角のあるトナー粒子の投影像を示す説明図である。
【符号の説明】
１ 熱交換用ジャケット
２ 攪拌槽
３ 回転軸
４ 攪拌翼
４０ 攪拌翼
４１１ 折り曲げ部
４２１ スリット
４２３ フィン
５０ 攪拌翼
５４１ 中孔部
５５ 攪拌翼
５ａ，５ｂ，５ｃ，５ｄ 攪拌翼
６ｂ，６ｃ，６ｄ 中孔部
７ 上部材料投入口
８ 下部材料投入口
９ 乱流形成部材
α 交差角
１２１ 感光体
１２２ 帯電器
１２３ 現像装置
１２４ 転写器
１２５ 分離器
１２６ クリーニング装置
１２６Ａ クリーニングブレード
１２６Ｂ 金属薄板部材
１２７ ＰＣＬ（プレチャージランプ）
１３０ 露光光学系
１９１ 支持部材
ａ クリーニングブレードの自由長
ｂ 金属薄板部材の自由長
ｔ₁ クリーニングブレードの厚さ
ｔ₂ 金属薄板部材の厚さ[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a cleaning device used for an electrophotographic copying machine, a printer, or the like.PlaceThe present invention relates to an image forming method and an image forming apparatus used.
[0002]
[Prior art]
In recent years, an organic photoreceptor containing an organic photoconductive substance (hereinafter also simply referred to as a photoreceptor) has been most widely used as an image carrier used in an electrophotographic image forming apparatus. Organic photoconductors have advantages over other photoconductors, such as easy development of materials suitable for various exposure light sources from visible light to infrared light, the ability to select materials without environmental pollution, and low manufacturing costs. However, the mechanical strength is weak, and the disadvantage is that the surface of the photoreceptor is easily deteriorated and scratches are likely to occur when copying and printing a large number of sheets.
[0003]
Further, since the organic photoconductor has a large contact energy with the toner that visualizes the electrostatic latent image formed on the photoconductor, the toner image is transferred onto a transfer material in the transfer process, and is then transferred onto the photoconductor. It is difficult to remove the residual toner, and various problems are likely to occur in cleaning the surface of the photoreceptor.
[0004]
On the other hand, in the electrophotographic image forming method, digital image forming has become mainstream due to recent progress in digital technology. The digital image forming method is based on visualizing small dot images of one pixel such as 400 dpi (number of dots per inch), and high image quality technology that faithfully reproduces these small dot images is required. Has been.
[0005]
On the other hand, regarding the deterioration of the surface of the organic photoreceptor due to cleaning, various techniques for increasing the mechanical strength of the photoreceptor surface have been proposed. As a technique for improving the surface wear of an organic photoreceptor, JP-A-9-258460 proposes a photoreceptor having a polycarbonate resin having a high hardness on the surface layer. Unlike the conventional organic photoconductor, the photoconductor having the polycarbonate resin resin layer has a small surface wear due to cleaning, so that a frictional force with a cleaning blade (hereinafter, simply referred to as a blade) is increased, and cleaning with the conventional cleaning blade is performed. Then, it is easy to generate defective cleaning such as blade turning and toner slipping from the vibration of the blade.
[0006]
Another technique for improving image quality is a technique related to a toner manufacturing technique. So far, so-called pulverized toner, which is obtained by classifying toner powder obtained by mixing binder resin and pigment, pulverizing after kneading, and classifying in the classification process has been mainly used for the formation of electrophotographic images. The toner thus obtained has a limit in making the particle size distribution of the toner particles uniform, and the particle size distribution and shape of the toner particles are insufficiently uniform. It is difficult to achieve sufficient image quality with an electrophotographic image using such pulverized toner.
[0007]
In recent years, an electrophotographic developer using a polymerized toner or an image forming method has been proposed as means for achieving uniform particle size distribution and shape of toner particles. Since the polymerized toner is produced by uniformly dispersing the raw material monomer in an aqueous system to produce a toner, a toner having a uniform toner particle size distribution and shape can be obtained.
[0008]
Here, a new technical problem has arisen when the polymerized toner is employed in an image forming apparatus using an organic photoreceptor. That is, as described above, the polymerized toner is formed in a substantially spherical shape because the toner shape is formed by the polymerization process of the monomer. As is well known, the spherical residual toner on the organic photoconductor tends to cause poor cleaning. In particular, the surface of an organic photoreceptor is easily worn, and if toner adheres to the unevenness of the surface generated by the wear, fine toner slipping that does not occur in an image occurs over a long period of time. The charging wire and the charging roller) are contaminated, and as a result, image unevenness occurs in the halftone image.
[0009]
Various proposals have been made so far in order to improve cleaning defects such as blade turning and toner slipping that occur in the image forming method using the above polymerized toner. In particular, proposals have been made to change the shape of the polymerized toner from a spherical shape to an elliptical shape, a proposal to change the surface shape of the polymerized toner to a concavo-convex shape, and the like, but these proposals are still not sufficient solutions.
[0010]
[Problems to be solved by the invention]
  The object of the present invention is to solve the above-mentioned problems, and when an organic photoreceptor and polymerized toner are used, the cleaning performance is maintained over a long period of time, and an excellent electrophotographic image can be formed without image defects.PaintingAn image forming method and an image forming apparatus are provided.
[0011]
[Means for Solving the Problems]
As a result of repeated studies to solve the above problems, the present inventors have secured a good cleaning property and maintained stable vibration of the cleaning blade by attaching a thin metal plate member to the cleaning blade of the cleaning device. It became possible to solve the above problems. That is, it has been found that the object of the present invention can be achieved by taking any one of the following configurations.
[0012]
  1.An image forming apparatus comprising an organic photoreceptor, and a cleaning device having a cleaning blade and a metal thin plate held by a holding member,The electrostatic latent image formed on the organic photoconductor is developed with a developer containing toner, and the toner image visualized by the development is transferred from the organic photoconductor to a transfer material, and then is transferred onto the organic photoconductor. The remaining tonerIn the image forming apparatus to be removed by the cleaning blade,
The cleaning blade and the metal plate member have a boundary surface that adheres to each other and a boundary surface that does not adhere to each other,
The cleaning bladeTheAdhering to the sheet metal member on the surface opposite to the surface in contact with the organic photoreceptor,
andTheWith a cleaning bladeTheThe free length part of the metal sheet member, Having a boundary surface that is not held by the holding member and does not adhere to each otherCharacterized by the free endImage forming apparatus.
[0013]
  2. 2. The step described in 1 above, wherein a step is provided between the tip of the cleaning blade and the tip of the metal thin plate member, and the step is such that the metal thin plate member is positioned farther from the organic photoreceptor.Image formationapparatus.
[0014]
  3. The electrostatic latent image formed on the organic photoconductor is developed with a developer containing toner, and the toner image visualized by the development is transferred from the organic photoconductor to a transfer material, and then is transferred onto the organic photoconductor. The remaining tonerIn the image forming method of removing by a cleaning device having a cleaning blade and a metal thin plate held by a holding member,
The cleaning blade and the metal plate member have a boundary surface that adheres to each other and a boundary surface that does not adhere to each other,
The cleaning blade adheres to the metal thin plate member at the boundary surface opposite to the surface in contact with the organic photoreceptor,
The free length portions of the cleaning blade and the thin metal plate member are free ends having boundary surfaces that are not held by the holding member and do not adhere to each other.An image forming method.
[0015]
  4).The toner according to 1 or 2 above, wherein a toner having a variation coefficient of a shape factor of toner particles of 16% or less and a number variation coefficient in a number particle size distribution of the toner particles of 27% or less is used as the toner. The image forming apparatus described.
[0016]
  5). As the toner,Contains 65% by number or more of toner particles having a shape factor in the range of 1.2 to 1.65. The image forming apparatus as described in 4 above, wherein the toner is used.
[0017]
  6). As the toner,50 toner particles without cornersA toner containing a number% or more is used.5The image forming apparatus described in 1.
[0018]
  7. SaidThe organic photoreceptor has a structure in which a photosensitive layer is provided on a conductive support, and the surface layer of the photosensitive layer contains a polycarbonate having a viscosity average molecular weight of 40,000 to 200,000.4 aboveAny one of -6The image forming apparatus described in 1.
[0020]
The present invention will be described in more detail.
By adopting the above-described configuration of the present invention, the present inventors do not cause excessive turning on the toner remaining on the organic photoreceptor and excessive frictional force generated between the organic photoreceptor and the cleaning blade. It has been found that the toner remaining on the organic photoreceptor can be effectively removed, and a good and stable image can be obtained over a long period of time. Hereinafter, the present invention will be described in detail.
[0021]
FIG. 1 is a schematic configuration diagram showing the overall configuration of the image forming apparatus of the present invention.
The image forming apparatus shown in FIG. 1 is a digital image forming apparatus, and includes an image reading unit A, an image processing unit B (not shown), an image forming unit C, and a transfer paper transport unit D as a transfer paper transport unit. It is configured.
[0022]
The upper part of the image reading unit A is provided with automatic document feeding means for automatically conveying the document. The document placed on the document placing table 111 is separated and conveyed by the document conveying roller 112 to the reading position 113a. The image is read. The document after the document reading is completed is discharged onto the document discharge tray 114 by the document transport roller 112.
[0023]
On the other hand, the image of the original when placed on the platen glass 113 is read at a speed v of the first mirror unit 115 including the illumination lamp and the first mirror constituting the scanning optical system, and the V-shaped first image is located. Reading is performed by moving the second mirror unit 116 composed of the two mirrors and the third mirror in the same direction at the speed v / 2.
[0024]
The read image is formed on the light receiving surface of the image sensor CCD, which is a line sensor, through the projection lens 117. The line-shaped optical image formed on the image sensor CCD is sequentially photoelectrically converted into an electric signal (luminance signal) and then A / D converted, and the image processing unit B performs processing such as density conversion and filter processing. Then, the image data is temporarily stored in the memory.
[0025]
In the image forming unit C, as an image forming unit, a drum-shaped photosensitive member (hereinafter also referred to as a photosensitive drum) 121 that is an image carrier, a charger 122 that is a charging unit, and a developing unit that is a developing unit are provided on the outer periphery thereof. A device 123, a transfer device 124 as transfer means, a separator 125 as separation means, a cleaning device 126 and a PCL (precharge lamp) 127 are arranged in the order of operation. The photoconductor 121 is formed by coating a photoconductive compound on a drum base. For example, an organic photoconductor (OPC) is preferably used, and is driven to rotate in the clockwise direction shown in the drawing.
[0026]
After the rotating photosensitive member 121 is uniformly charged by the charger 122, the exposure optical system 130 performs image exposure based on the image signal called from the memory of the image processing unit B. The exposure optical system 130 as writing means uses a laser diode (not shown) as a light source, passes through a rotating polygon mirror 131, an fθ lens (no symbol), and a cylindrical lens (no symbol), and the optical path is bent by a reflection mirror 132 to perform main scanning. Thus, image exposure is performed on the photoconductor 121 at the position Ao, and a latent image is formed by rotation (sub-scanning) of the photoconductor 121. In one example of the present embodiment, the character portion is exposed to form a latent image.
[0027]
The latent image on the photoconductor 121 is reversely developed by the developing device 123, and a visible toner image is formed on the surface of the photoconductor 121. In the transfer paper transport section D, paper feed units 141 (A), 141 (B), and 141 (C) are provided below the image forming unit as transfer paper storage means for storing transfer paper P of different sizes. Further, a manual paper feeding unit 142 that performs manual paper feeding is provided on the side, and the transfer paper P selected from any of them is fed along the transport path 140 by the guide roller 143 and fed. The transfer paper P is temporarily stopped by a pair of registration rollers 144 that corrects the inclination and bias of the transfer paper to be transferred, and then fed again, and is guided to the transport path 140, the pre-transfer roller 143a, and the transfer entrance guide plate 146. The toner image on the photoconductor 121 is transferred to the transfer paper P by the transfer device 124 at the transfer position Bo, and then the charge is removed by the separator 125. Separated, it is conveyed to the fixing device 150 by a conveying device 145.
[0028]
The fixing device 150 has a fixing roller 151 and a pressure roller 152. By passing the transfer paper P between the fixing roller 151 and the pressure roller 152, the toner is fused by heating and pressing. . After the toner image has been fixed, the transfer paper P is discharged onto a paper discharge tray 164.
[0029]
FIG. 2 is a configuration diagram of a cleaning device using the cleaning blade of the present invention.
[0030]
In the cleaning device, a cleaning blade 126A and a thin metal plate member 126B are attached to a support member 191 (generally a metal plate is used). As the material of the cleaning blade, a rubber elastic body is used, and as the material, urethane rubber, silicon rubber, fluorine rubber, chloroprene rubber, butadiene rubber, etc. are known. Of these, urethane rubber is used as another rubber. It is particularly preferable in that it has superior wear characteristics. For example, urethane rubber obtained by reacting and curing polycaprolactone ester and polyisocyanate described in JP-A-59-30574 is preferable.
[0031]
The thin metal plate member of the present invention is a metal plate having a thickness of 0.01 to 2 mm, particularly preferably 0.02 to 0.5 mm, and means a member having a shape that can be bonded to a cleaning blade. As the material of the metal thin plate, any metal material can be used as long as it is a flexible metal thin plate. Preferably, a SUS300 series, SUS400 series stainless steel plate, an aluminum plate, a phosphor bronze plate, or the like is used.
[0032]
In the present invention, when the thin metal plate member 126B and the cleaning blade 126A are fixed to the support member 191, the thin metal plate member is disposed so that the cleaning blade is in close contact with the photoreceptor on the surface opposite to the contact surface. Install and hold. At this time, the cleaning blade and the thin metal plate member are securely bonded with an adhesive or the like on the support member 191, that is, at the boundary surface of C (shown by a thick line) in FIG. 2. As a result, there is a mechanism that can reliably propagate and absorb the vibration generated by the blade to the thin metal plate member. Further, the free length portions of the cleaning blade and the metal thin plate member, that is, the boundary surfaces of the free lengths a and b are not bonded to each other but are free ends. As a result, when the environment in which the cleaning device of the present invention operates becomes low temperature and low humidity or high temperature and high humidity, the cleaning blade and the metal thin plate member can be prevented from contracting or expanding due to expansion, and generally set at normal temperature and normal humidity. Cleaning conditions are maintained stably.
[0033]
The proper pressure contact condition of the cleaning blade to the surface of the photoreceptor is determined by a delicate balance of various characteristics and is quite narrow. The setting varies depending on characteristics such as the thickness of the cleaning blade, and requires precision. However, the thickness of the cleaning blade can vary slightly when it is manufactured, so it cannot always be set under the proper conditions. It may be out of the proper area. In particular, when combined with an organic photosensitive layer using a high molecular weight binder resin, if it is out of the proper area, it causes blade turning and toner slipping.
[0034]
Therefore, the present invention is an effective means for canceling the variation in the characteristics of the cleaning blade, and effectively absorbs the vibration of the blade caused by the thin metal plate member even if the thickness of the cleaning blade varies. Thus, the setting condition of the cleaning blade on the photosensitive member surface can be stably maintained in the appropriate region.
[0035]
In the present invention, it is preferable that the tip of the cleaning blade that is in pressure contact with the surface of the photoconductor is in pressure contact with a load applied in a direction opposite to the rotation direction of the photoconductor (counter direction). As shown in FIG. 2, it is preferable to form a pressure contact surface when the tip of the cleaning blade is pressed against the photosensitive member.
[0036]
The positional relationship between the cleaning blade and the thin metal plate member of the present invention is configured such that a step is provided between the tips of both as shown in FIG. Furthermore, the free length of the thin metal plate member is shorter than the free length of the cleaning blade. With this configuration, the cleaning blade vibration is absorbed by the metal thin plate member without hindering deformation at the tip of the cleaning blade (deformation caused by pressure contact with the photosensitive member), and the cleaning blade vibration. Can be stabilized.
[0037]
In the cleaning device of the present invention, the ratio of the free length of the cleaning blade to the thin metal plate member satisfies the formula 1 when the free length of the cleaning blade is a and the free length of the thin metal plate member is b as shown in FIG. It is preferable that it is designed. The free length is the length of the portion where the cleaning blade and the metal thin plate member are not held by the support member 191. As shown in FIG. 2, the cleaning blade and metal before deformation from the end B of the support member 191 are shown. The length to the front-end | tip point of each thin plate member is shown.
[0038]
Formula 1
0.1 <b / a ≦ 0.9
Deformation at the tip of the cleaning blade (deformation caused by pressure contact with the photosensitive member) by designing so that b / a is in the above range, that is, b / a exceeds 0.1 and is 0.9 or less. It was found that the vibration of the cleaning blade was absorbed by the metal thin plate member without hindering the toner, and stable cleaning performance without blade turning or toner slippage could be realized. Furthermore, in the present invention, the range of 0.3 to 0.8 is more preferable. On the other hand, if b / a is 0.1 or less, toner slippage tends to occur, and if b / a is larger than 0.9, blade turning tends to occur.
[0039]
On the other hand, the ratio of the thickness of the cleaning blade to the thin metal plate member is the thickness of the cleaning blade t as shown in FIG.₁, The thickness of the metal sheet member is t₂Then, it is preferable to satisfy Formula 2.
[0040]
Formula 2
1/200 ≦ t₂/ T₁≦ 1
t₂/ T₁Within the above range, i.e. t₂/ T₁The cleaning blade is stably held by the support member, and the vibration of the cleaning blade is absorbed by the metal thin plate member so that the blade is not turned over or slipped out of the toner. It was found that stable cleaning can be realized. Furthermore, t₂/ T₁Is preferably in the range of 1/100 to 1/4. On the other hand, t₂/ T₁Is less than 1/200, toner passes easily and t₂/ T₁If is larger than 1, blade turning is likely to occur.
[0041]
In the present invention, preferable values of the contact load P and the contact angle θ of the cleaning blade to the photosensitive member are P = 5 to 40 N / m and θ = 5 to 35 °.
[0042]
The contact load P is a normal vector value of the pressure contact force P ′ when the blade 126A is brought into contact with the photosensitive drum 121.
[0043]
The contact angle θ represents an angle formed between the tangent line X at the contact point A of the photosensitive member and the blade before deformation (shown by a dotted line in the drawing). Reference numeral 172 denotes a fixing screw for fixing the support member, and 193 denotes a load spring.
[0044]
The cleaning blade free length a represents the length of the tip point of the blade before deformation from the position of the end B of the support member 191 as shown in FIG. A preferable value of the free length is a = 6 to 15 mm. The thickness of the cleaning blade is preferably 0.5 to 10 mm. Here, the thickness of the cleaning blade and the thin metal plate member of the present invention indicates a direction perpendicular to the bonding surface of the support member 191 as shown in FIG.
[0045]
The cleaning blade used in the present invention is preferably a rubber elastic body. By simultaneously controlling the physical properties of the cleaning blade and the metal thin plate member, the cleaning conditions of the present invention can be adjusted better, and the toner cleaning performance can be controlled more effectively. .
[0046]
Further, as another physical property of the cleaning blade, the hardness is preferably in the range of 55-90 JIS hardness at 25 ± 5 ° C. When it is smaller than 55, the cleaning performance tends to be lowered, and when it is larger than 90, the blade is easily reversed. The rebound resilience of the cleaning blade is preferably in the range of 25-80. When the impact resilience exceeds 80, the blade is easily reversed, and when it is less than 25, the cleaning performance is deteriorated. Young's modulus is 294-588 N / cm²The thing of the range of is preferable.
[0047]
If necessary, the cleaning blade may be sprayed with a fluorine-based lubricant on the edge of the cleaning blade that is in contact with the photosensitive member, or further, a fluorine-based lubricant may be applied to the tip over the entire width direction. It is preferable to apply a dispersion in which a polymer and fluorine resin powder are dispersed in a fluorine solvent.
[0048]
Next, the organic photoreceptor of the present invention will be described.
In the present invention, an organic electrophotographic photoreceptor (organic photoreceptor) is an electrophotographic structure in which an organic compound has at least one of a charge generation function and a charge transport function essential to the construction of an electrophotographic photoreceptor. It means a photoreceptor, and all known organic electrophotographic photoreceptors such as a photoreceptor composed of a known organic charge generating material or an organic charge transport material, a photoreceptor composed of a polymer complex with a charge generating function and a charge transport function, etc. contains.
[0049]
The constitution of the organic photoreceptor used in the present invention is described below.
Conductive support
The conductive support used in the photoreceptor of the present invention may be either a sheet or a cylinder, but a cylindrical conductive support is more preferable for designing an image forming apparatus in a compact manner.
[0050]
The cylindrical conductive support of the present invention means a cylindrical support necessary for forming an endless image by rotating, and the straightness is in the range of 0.1 mm or less and the deflection is 0.1 mm or less. A conductive support is preferred. Exceeding the roundness and shake range makes it difficult to form a good image.
[0051]
As the conductive material, a metal drum such as aluminum or nickel, a plastic drum deposited with aluminum, tin oxide, indium oxide or the like, or a paper / plastic drum coated with a conductive substance can be used. The conductive support preferably has a specific resistance of 103 Ωcm or less at room temperature.
[0052]
As the conductive support used in the present invention, one having an alumite film that has been sealed on the surface thereof may be used. The alumite treatment is usually performed in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, sulfamic acid, etc., but anodizing treatment in sulfuric acid gives the most preferable result. In the case of anodizing in sulfuric acid, the sulfuric acid concentration is preferably 100 to 200 g / l, the aluminum ion concentration is 1 to 10 g / l, the liquid temperature is about 20 ° C., and the applied voltage is preferably about 20 V. It is not limited. The average film thickness of the anodized film is usually 20 μm or less, particularly preferably 10 μm or less.
[0053]
Middle class
In the present invention, an intermediate layer having a barrier function may be provided between the conductive support and the photosensitive layer.
[0054]
In the present invention, in order to improve the adhesion between the conductive support and the photosensitive layer, or to prevent charge injection from the support, an intermediate layer (including an undercoat layer) is provided between the support and the photosensitive layer. Including) can also be provided. Examples of the material for the intermediate layer include polyamide resins, vinyl chloride resins, vinyl acetate resins, and copolymer resins containing two or more of these resin repeating units. Of these subbing resins, a polyamide resin is preferable as a resin capable of reducing the increase in residual potential due to repeated use. The film thickness of the intermediate layer using these resins is preferably 0.01 to 0.5 μm.
[0055]
The intermediate layer most preferably used in the present invention includes an intermediate layer using a curable metal resin obtained by thermally curing an organometallic compound such as a silane coupling agent or a titanium coupling agent. As for the film thickness of the intermediate | middle layer using curable metal resin, 0.1-2 micrometers is preferable.
[0056]
Photosensitive layer
The photosensitive layer configuration of the photoreceptor of the present invention may be a single layer photosensitive layer configuration in which a charge generation function and a charge transport function are provided on one layer on the intermediate layer. It is preferable that the generation layer (CGL) and the charge transport layer (CTL) be separated. By adopting a configuration in which the functions are separated, an increase in the residual potential due to repeated use can be controlled to be small, and other electrophotographic characteristics can be easily controlled according to the purpose. In the negatively charged photoconductor, it is preferable that a charge generation layer (CGL) is formed on the intermediate layer, and a charge transport layer (CTL) is formed thereon. In the positively charged photoconductor, the order of the layer configuration is the reverse of that in the negatively charged photoconductor. The most preferred photosensitive layer structure of the present invention is a negatively charged photoreceptor structure having the function separation structure.
[0057]
The structure of the photosensitive layer of the function-separated negatively charged photoreceptor will be described below.
Charge generation layer
Charge generation layer: The charge generation layer contains a charge generation material (CGM). Other substances may contain a binder resin and other additives as necessary.
[0058]
A known charge generation material (CGM) can be used as the charge generation material (CGM). For example, a phthalocyanine pigment, an azo pigment, a perylene pigment, an azulenium pigment, or the like can be used. Among these, the CGM that can minimize the increase in residual potential due to repeated use has a three-dimensional and potential structure that can form a stable aggregate structure among a plurality of molecules. Specifically, a phthalocyanine having a specific crystal structure. CGM of pigments and perylene pigments. For example, CGMs such as titanyl phthalocyanine having a maximum peak at a Bragg angle 2θ of 27.2 ° with respect to Cu—Kα rays and benzimidazole perylene having a maximum peak at 2θ of 12.4 have little deterioration due to repeated use. Potential increase can be reduced.
[0059]
When a binder is used as the CGM dispersion medium in the charge generation layer, a known resin can be used as the binder, but the most preferred resins include formal resin, butyral resin, silicone resin, silicone-modified butyral resin, phenoxy resin, and the like. Can be mentioned. The ratio of the binder resin to the charge generating material is preferably 20 to 600 parts by mass with respect to 100 parts by mass of the binder resin. By using these resins, the increase in residual potential associated with repeated use can be minimized. The thickness of the charge generation layer is preferably 0.01 μm to 2 μm.
[0060]
Charge transport layer
Charge transport layer: The charge transport layer contains a charge transport material (CTM) and a binder resin in which CTM is dispersed to form a film. Other substances may contain additives such as antioxidants as necessary.
[0061]
A known charge transport material (CTM) can be used as the charge transport material (CTM). For example, a triphenylamine derivative, a hydrazone compound, a styryl compound, a benzidine compound, a butadiene compound, or the like can be used. These charge transport materials are usually dissolved in a suitable binder resin to form a layer. Among these, the CTM capable of minimizing the increase in residual potential due to repeated use has a high mobility and an ionization potential difference from the combined CGM of 0.5 (eV) or less, preferably 0 .25 (eV) or less.
[0062]
The ionization potential of CGM and CTM is measured with a surface analyzer AC-1 (manufactured by Riken Keiki Co., Ltd.).
[0063]
Examples of the resin used for the charge transport layer (CTL) include polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, and polycarbonate. Resin, silicone resin, melamine resin, and copolymer resin containing two or more of repeating units of these resins. In addition to these insulating resins, high molecular organic semiconductors such as poly-N-vinylcarbazole can be used.
[0064]
Most preferred as a binder for these CTLs is a polycarbonate resin. The polycarbonate resin is most preferable in improving the dispersibility and electrophotographic characteristics of CTM. In the case of a photoreceptor having a charge transport layer as a surface layer, a polycarbonate resistant to mechanical wear is preferable. As such a polycarbonate, a polycarbonate having a viscosity average molecular weight of 40,000 to 200,000 is preferable. The ratio of the binder resin to the charge transport material is preferably 10 to 200 parts by mass with respect to 100 parts by mass of the binder resin. The thickness of the charge transport layer is preferably 10 to 40 μm.
[0065]
Protective layer
Various resin layers can be provided as a protective layer of the photoreceptor. In particular, by providing a cross-linked resin layer, the organic photoreceptor of the present invention having high mechanical strength can be obtained.
[0066]
Examples of the solvent or dispersion medium used for forming the intermediate layer, photosensitive layer, protective layer and the like of the present invention include n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N-dimethylformamide, Acetone, methyl ethyl ketone, methyl isopropyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1,2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene , Tetrachloroethane, tetrahydrofuran, dioxolane, dioxane, methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl cello Lube, and the like. Although this invention is not limited to these, Dichloromethane, 1, 2- dichloroethane, methyl ethyl ketone, etc. are used preferably. These solvents may be used alone or as a mixed solvent of two or more.
[0067]
Next, as a coating processing method for producing the organic electrophotographic photoreceptor of the present invention, a coating processing method such as dip coating, spray coating, circular amount regulation type coating or the like is used. In order to prevent the lower layer film from being dissolved as much as possible, it is preferable to use a coating method such as spray coating or circular amount regulation type (a typical example is a circular slide hopper type) in order to achieve uniform coating processing. It is most preferable that the protective layer of the present invention uses the circular amount regulation type coating method. The circular amount regulation type coating is described in detail in, for example, Japanese Patent Application Laid-Open No. 58-189061.
[0068]
Next, the toner used in the present invention will be described.
The toner of the present invention is preferably a polymerized toner having a relatively uniform particle size distribution and shape of individual toner particles. Here, the polymerized toner means a toner obtained by forming a binder resin for toner and forming the toner shape by polymerization of a raw material monomer of the binder resin and subsequent chemical treatment. More specifically, it means a toner obtained through a polymerization reaction such as suspension polymerization or emulsion polymerization and, if necessary, a fusing step between particles carried out after the polymerization reaction.
[0069]
As the polymerization toner used in the cleaning device using the cleaning blade of the present invention, a toner having a specific shape is preferable. The polymerized toner that can be preferably used in the present invention will be described below.
[0070]
As a preferred polymerized toner applied to the present invention, a toner having 65% by number or more of toner particles having a shape factor in the range of 1.2 to 1.6 and a coefficient of variation of the shape factor of 16% or less is used. It is to be. In the present invention, it has been found that even when such a polymerized toner is used, the vibration of the cleaning blade can be stabilized and excellent cleaning performance can be exhibited.
[0071]
Also, the vibration stability of the cleaning blade varies depending on the particle size of the toner particles. The smaller the particle size, the higher the adhesion force to the image carrier, so that the vibration is likely to be excessive and the toner is contained in the cleaning blade. There is a high probability of passing through. However, when the toner particle diameter is large, such slip-through is reduced, but there is a problem that image quality such as resolution is lowered.
[0072]
As a result of studying from the above viewpoint, the toner having a variation coefficient of the toner shape factor of 16% or less and a toner having a number variation coefficient of 27% or less in the number particle size distribution of the toner, It has been found that high-quality image quality can be formed over a long period of time with excellent fine line reproducibility.
[0073]
In addition, by using toner particles with no corners at 50% by number or more and controlling the number variation coefficient in the number particle size distribution to 27% or less, excellent cleaning properties and fine line reproducibility, and high quality image quality for a long time Can be formed over.
[0074]
The shape factor of the toner of the present invention is represented by the following formula and indicates the degree of roundness of the toner particles.
[0075]
Shape factor = ((maximum diameter / 2)²× π) / projection area
Here, the maximum diameter refers to the width of a particle that maximizes the interval between the parallel lines when the projected image of the toner particles on the plane is sandwiched between two parallel lines. The projected area refers to the area of the projected image of the toner particles on the plane.
[0076]
In the present invention, this shape factor is obtained by taking a photograph in which the toner particles are magnified 2000 times with a scanning electron microscope, and then using “SCANNING IMAGE ANALYZER” (manufactured by JEOL Ltd.) based on this photograph. It was measured by performing analysis. At this time, the shape factor of the present invention was measured by the above formula using 100 toner particles.
[0077]
As a preferable polymerized toner of the present invention, the number of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, and more preferably 70% by number or more.
[0078]
When the number of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, the triboelectric chargeability on the developer conveying member and the like becomes more uniform, and excessively charged toner is accumulated. In addition, since it becomes easier to replace the toner from the surface of the developer conveying member, problems such as development ghost are less likely to occur. Further, the toner particles are less likely to be crushed, the contamination of the charging member is reduced, and the chargeability of the toner is stabilized.
[0079]
The method for controlling the shape factor is not particularly limited. For example, a method in which toner particles are sprayed into a hot air stream, a method in which toner particles are repeatedly applied with mechanical energy due to impact force in a gas phase, or a method in which a toner is not dissolved in a solvent and a swirl flow is applied. Thus, there is a method in which a toner having a shape factor of 1.2 to 1.6 is prepared and added to a normal toner so as to be within the range of the present invention. In addition, the overall shape is controlled at the stage of adjusting the so-called polymerization method toner, and the toner whose shape factor is adjusted to 1.0 to 1.6 or 1.2 to 1.6 is similarly added to the normal toner. There is a way to adjust.
[0080]
The variation coefficient of the shape factor of the polymerized toner preferably used in the present invention is calculated from the following equation.
[0081]
Coefficient of variation = [S / K] x 100 (%)
[In the formula, S represents the standard deviation of the shape factor of 100 toner particles, and K represents the average value of the shape factor. ]
The variation coefficient of the shape factor is 16% or less, preferably 14% or less. When the variation coefficient of the shape factor is 16% or less, voids in the transferred toner layer are reduced, fixing property is improved, and offset is less likely to occur. In addition, the charge amount distribution becomes sharp and the image quality is improved.
[0082]
Toner particles that are being formed in the process of polymerizing, fusing, and controlling the shape of resin particles (polymer particles) in order to uniformly control the shape factor of the toner and the coefficient of variation of the shape factor without variation in lots. An appropriate process end time may be determined while monitoring the characteristics of the (colored particles).
[0083]
Monitoring means that a measuring device is incorporated in-line, and process conditions are controlled based on the measurement result. In other words, in the case of a polymerization method toner that is formed by incorporating measurement such as shape in-line, for example, by associating or fusing resin particles in an aqueous medium, the shape and particle size are measured while performing sequential sampling in the fusing step. The reaction is stopped when the desired shape is obtained.
[0084]
Although it does not specifically limit as a monitoring method, The flow type particle image analyzer FPIA-2000 (made by Toa Medical Electronics Co., Ltd.) can be used. This apparatus is suitable because the shape can be monitored by performing image processing in real time while passing the sample liquid. That is, a pump or the like is used from the reaction field and is constantly monitored to measure the shape and the like, and the reaction is stopped when the desired shape is obtained.
[0085]
The number particle size distribution and the number variation coefficient of the toner of the present invention are measured by a Coulter Counter TA-II or Coulter Multisizer (manufactured by Coulter Inc.). In the present invention, a Coulter Multisizer is used, and an interface (manufactured by Nikkaki Co., Ltd.) that outputs a particle size distribution and a personal computer are connected. The aperture used in the Coulter Multisizer was 100 μm, and the volume and number of toners of 2 μm or more were measured to calculate the particle size distribution and average particle size. The number particle size distribution represents the relative frequency of the toner particles with respect to the particle size, and the number average particle size represents the median diameter in the number particle size distribution.
[0086]
The number variation coefficient in the toner number particle size distribution is calculated from the following equation.
Number variation coefficient = [S / Dn] × 100 (%)
[In the formula, S represents the standard deviation in the number particle size distribution, and Dn represents the number average particle size (μm). ]
The number variation coefficient of the toner of the present invention is 27% or less, preferably 25% or less. When the number variation coefficient is 27% or less, voids in the transferred toner layer are reduced, fixing properties are improved, and offset is less likely to occur. In addition, the charge amount distribution becomes sharp, the transfer efficiency is increased, and the image quality is improved.
[0087]
The method for controlling the number variation coefficient of the present invention is not particularly limited. For example, a method of classifying toner particles by wind force can be used, but classification in a liquid is effective for reducing the number variation coefficient. As a method of classifying in this liquid, there is a method of separating and collecting toner particles according to a difference in sedimentation speed caused by a difference in toner particle diameter by using a centrifuge and controlling the rotation speed.
[0088]
In particular, when a toner is produced by a suspension polymerization method, a classification operation is indispensable in order to make the number variation coefficient in the number particle size distribution 27% or less. In the suspension polymerization method, it is necessary to disperse a polymerizable monomer in an oil droplet having a desired size as a toner in an aqueous medium before polymerization. That is, mechanical shearing with a homomixer or homogenizer is repeated for large oil droplets of a polymerizable monomer to reduce the oil droplets to the size of toner particles. In the method using shearing, the number particle size distribution of the obtained oil droplets is wide, and therefore the particle size distribution of the toner obtained by polymerizing the oil droplets is also wide. For this reason, classification operation is essential.
[0089]
The toner particles having no corners of the present invention refer to toner particles that do not substantially have protrusions that concentrate electric charges or that easily wear due to stress, that is, as shown in FIG. In addition, when the major axis of the toner particle T is L, the circle C having a radius (L / 10) is rolled into the circle C while being inwardly touching the peripheral line of the toner particle T at one point. Is a toner particle having no corners. “A case where the protrusion does not substantially protrude” refers to a case where the protrusion having the protruding circle is one or less. The “major diameter of toner particles” refers to the width of a particle that maximizes the interval between the parallel lines when the projected image of the toner particles on a plane is sandwiched between two parallel lines. FIGS. 13B and 13C show projection images of toner particles having corners, respectively.
[0090]
The measurement of toner without corners was performed as follows. First, an enlarged photograph of the toner particles is taken with a scanning electron microscope, and further enlarged to obtain a 15,000 times photographic image. The photographic image is then measured for the presence or absence of the corners. This measurement was performed on 100 toner particles.
[0091]
In the toner of the present invention, the proportion of toner particles having no corners is 50% by number or more, preferably 70% by number or more. When the ratio of toner particles having no corners is 50% by number or more, generation of fine particles is less likely to occur due to stress with the developer conveying member, and the toner having excessive adhesion to the surface of the developer conveying member. In addition, the contamination of the developer conveying member can be suppressed, and the charge amount can be sharpened. In addition, toner particles that easily wear and break and toner particles having a portion where charges are concentrated are reduced, the charge amount distribution becomes sharp, the chargeability is stable, and good image quality can be formed over a long period of time.
[0092]
A method for obtaining toner having no corners is not particularly limited. For example, as described above as a method for controlling the shape factor, a method in which toner particles are sprayed into a hot air stream, a method in which toner particles are repeatedly applied with mechanical energy by impact force in a gas phase, or a toner is dissolved. It can be obtained by adding in a solvent that does not, and applying a swirling flow.
[0093]
Further, in the polymerization toner formed by associating or fusing the resin particles, the fusing particle surface has many irregularities at the fusing stop stage, and the surface is not smooth, but the temperature in the shape control step, By making the conditions such as the number of revolutions of the stirring blade and the stirring time appropriate, a toner having no corners can be obtained. These conditions vary depending on the physical properties of the resin particles. For example, by setting the number of revolutions to be higher than the glass transition temperature of the resin particles, the surface becomes smooth and a toner having no corners can be formed.
[0094]
The toner of the present invention preferably has a number average particle diameter of 3 to 8 μm. When the toner particles are formed by a polymerization method, the particle size can be controlled by the concentration of the aggregating agent, the amount of the organic solvent added, the fusing time, and further the composition of the polymer itself.
[0095]
When the number average particle diameter is 3 to 8 μm, it is possible to reduce the presence of toner having excessive adhesion to the developer conveying member or toner having low adhesion force in the fixing process, and developability over a long period of time. And the transfer efficiency is increased, the image quality of halftone is improved, and the image quality of fine lines and dots is improved.
[0096]
As the polymerized toner preferably used in the present invention, when the particle diameter of the toner particle is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23. In the histogram showing the particle size distribution of toner particles, the relative frequency of toner particles (m₁) And the relative frequency (m of toner particles contained in the next most frequent class after the most frequent class)₂) And the toner (M) is preferably 70% or more.
[0097]
Relative frequency (m₁) And relative frequency (m₂) Is 70% or more, the dispersion of the particle size distribution of the toner particles is narrowed. Therefore, the use of the toner in the image forming process can reliably suppress the occurrence of selective development. .
[0098]
In the present invention, the histogram showing the particle size distribution based on the number is a natural logarithm lnD (D: particle size of individual toner particles) having a plurality of classes (0 to 0.23: 0.23) at intervals of 0.23. 0.46: 0.46-0.69: 0.69-0.92: 0.92-1.15: 1.15-1.38: 1.38-1.61: 1.61-1. 84: 1.84 to 2.07: 2.07 to 2.30: 2.30 to 2.53: 2.53 to 2.76, and so on). This histogram was created by transferring the particle size data of the sample measured by the Coulter Multisizer to a computer via the I / O unit according to the following conditions and using the particle size distribution analysis program in the computer. is there.
[0099]
〔Measurement condition〕
(1) Aperture: 100 μm
(2) Sample preparation method: Electrolyte [ISOTON R-11 (manufactured by Coulter Scientific Japan)] 50-100 ml, an appropriate amount of a surfactant (neutral detergent) was added and stirred, and a measurement sample 10-20 mg was added thereto. Add This system is prepared by dispersing for 1 minute with an ultrasonic disperser.
[0100]
Among the methods for controlling the shape factor, the polymerization toner is preferable because it is simple as a production method and has excellent surface uniformity as compared with the pulverized toner.
[0101]
The toner of the present invention is produced by subjecting a monomer to emulsion polymerization in a suspension polymerization method or a liquid obtained by adding an emulsified liquid of necessary additives to produce fine polymer particles. It can manufacture by the method of adding and associating. A method of preparing by mixing with a dispersion liquid such as a release agent and a colorant necessary for the composition of the toner at the time of association, and a toner component such as a release agent and a colorant dispersed in the monomer And a method of emulsion polymerization. Here, the association means that a plurality of resin particles and colorant particles are fused.
[0102]
In addition, the aqueous medium as used in the field of this invention shows what contained 50 mass% or more of water at least.
[0103]
That is, various constituent materials such as a colorant and, if necessary, a release agent, a charge control agent, and a polymerization initiator are added to the polymerizable monomer, and a homogenizer, a sand mill, a sand grinder, an ultrasonic disperser, etc. Various constituent materials are dissolved or dispersed in the polymerizable monomer. The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in oil droplets having a desired size as a toner in an aqueous medium containing a dispersion stabilizer using a homomixer or a homogenizer. Thereafter, the stirring mechanism is transferred to a reactor that is a stirring blade described later, and the polymerization reaction is advanced by heating. After completion of the reaction, the dispersion stabilizer is removed, filtered, washed, and dried to prepare the toner of the present invention.
[0104]
Further, as a method for producing the toner of the present invention, a method of preparing by associating or fusing resin particles in an aqueous medium can also be mentioned. The method is not particularly limited, and examples thereof include methods disclosed in JP-A-5-265252, JP-A-6-329947, and JP-A-9-15904. That is, a method of associating a plurality of fine particles composed of resin particles and colorants, etc., or particles composed of resin and colorant, in particular, after dispersing them in water using an emulsifier, the critical aggregation concentration The above flocculant is added for salting out, and at the same time, the formed polymer itself is heated and fused at a temperature higher than the glass transition temperature to gradually grow the particle size while forming fused particles. Then, a large amount of water is added to stop the particle size growth, and the shape is controlled by smoothing the particle surface while heating and stirring, and the particles are heated and dried in a fluid state while containing water. The toner of the invention can be formed. Here, an organic solvent that is infinitely soluble in water may be added simultaneously with the flocculant.
[0105]
As the polymerizable monomer constituting the resin, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decyl Styrene, styrene or styrene derivatives such as pn-dodecylstyrene, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, Methacrylic acid ester derivatives such as lauryl tacrylate, phenyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, acrylic Acrylates such as isobutyl acid, n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate, phenyl acrylate, olefins such as ethylene, propylene, isobutylene, vinyl chloride, vinylidene chloride, Halogenated vinyls such as vinyl bromide, vinyl fluoride, vinylidene fluoride, vinyl esters such as vinyl propionate, vinyl acetate, vinyl benzoate, vinyl methyl ether, vinyl ethyl ether Vinyl ethers such as tellurium, vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone, vinyl hexyl ketone, N-vinyl compounds such as N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone, vinyl naphthalene, vinyl pyridine, etc. There are acrylic acid or methacrylic acid derivatives such as vinyl compounds, acrylonitrile, methacrylonitrile, acrylamide and the like. These vinyl monomers can be used alone or in combination.
[0106]
Further, it is more preferable to use a combination of monomers having an ionic dissociation group as the polymerizable monomer constituting the resin. For example, it has a substituent such as a carboxyl group, a sulfonic acid group, a phosphoric acid group as a constituent group of the monomer, specifically, acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, fumar Acid, maleic acid monoalkyl ester, itaconic acid monoalkyl ester, styrene sulfonic acid, allyl sulfosuccinic acid, 2-acrylamido-2-methylpropane sulfonic acid, acid phosphooxyethyl methacrylate, 3-chloro-2-acid phosphooxy And propyl methacrylate.
[0107]
Furthermore, multifunctional such as divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol diacrylate, etc. It is also possible to use a crosslinkable resin by using a functional vinyl.
[0108]
These polymerizable monomers can be polymerized using a radical polymerization initiator. In this case, an oil-soluble polymerization initiator can be used in the suspension polymerization method. Examples of the oil-soluble polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carboxyl). Nitriles), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azo- or diazo-based polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate , Cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis- (4,4- t-butylperoxycyclohexyl) propane, tris The (t-butylperoxy) triazine peroxide polymerization initiator or a peroxide, such as and the like polymeric initiator having a side chain.
[0109]
Moreover, when using an emulsion polymerization method, a water-soluble radical polymerization initiator can be used. Examples of the water-soluble polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetate, azobiscyanovaleric acid and its salts, hydrogen peroxide and the like.
[0110]
Dispersion stabilizers include tricalcium phosphate, magnesium phosphate, zinc phosphate, aluminum phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate , Bentonite, silica, alumina and the like. Furthermore, those generally used as surfactants such as polyvinyl alcohol, gelatin, methylcellulose, sodium dodecylbenzenesulfonate, ethylene oxide adduct, and higher alcohol sodium sulfate can be used as the dispersion stabilizer.
[0111]
As the resin excellent in the present invention, those having a glass transition point of 20 to 90 ° C. are preferred, and those having a softening point of 80 to 220 ° C. are preferred. The glass transition point is measured by a differential calorimetric analysis method, and the softening point can be measured by a Koka flow tester. Further, these resins preferably have a molecular weight measured by gel permeation chromatography of 1,000 to 100,000 in terms of number average molecular weight (Mn) and 2000 to 1,000,000 in terms of weight average molecular weight (Mw). Further, the molecular weight distribution is preferably such that Mw / Mn is 1.5 to 100, particularly 1.8 to 70.
[0112]
The flocculant used is not particularly limited, but those selected from metal salts are preferably used. Specifically, as a monovalent metal, for example, an alkali metal salt such as sodium, potassium or lithium, as a divalent metal, for example, an alkaline earth metal salt such as calcium or magnesium, or a divalent metal such as manganese or copper. And salts of trivalent metals such as iron and aluminum, and specific salts include sodium chloride, potassium chloride, lithium chloride, calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate, etc. Can be mentioned. These may be used in combination.
[0113]
These flocculants are preferably added in an amount equal to or higher than the critical aggregation concentration. The critical flocculation concentration is an index relating to the stability of the aqueous dispersion, and indicates a concentration at which flocculation occurs when a flocculant is added. This critical aggregation concentration varies greatly depending on the emulsified components and the dispersant itself. For example, it is described in Seizo Okamura et al., “Polymer Chemistry 17, 601 (1960) edited by Polymer Society” and the like, and a detailed critical aggregation concentration can be obtained. As another method, a desired salt is added to the target particle dispersion at different concentrations, the ζ (zeta) potential of the dispersion is measured, and the salt concentration at which this value changes is defined as the critical aggregation concentration. You can ask for it.
[0114]
The addition amount of the flocculant of the present invention may be not less than the critical aggregation concentration, but is preferably 1.2 times or more, more preferably 1.5 times or more the critical aggregation concentration.
[0115]
The solvent that dissolves infinitely means a solvent that dissolves infinitely in water, and in the present invention, a solvent that does not dissolve the formed resin is selected. Specific examples include alcohols such as methanol, ethanol, propanol, isopropanol, t-butanol, methoxyethanol, and butoxyethanol, nitriles such as acetonitrile, and ethers such as dioxane. In particular, ethanol, propanol, and isopropanol are preferable.
[0116]
The addition amount of the infinitely soluble solvent is preferably 1 to 100% by volume with respect to the polymer-containing dispersion to which the flocculant is added.
[0117]
In order to make the shape uniform, it is preferable to fluidly dry a slurry in which 10% by mass or more of water is present after preparing and filtering colored particles. Those having a polar group are preferred. The reason for this is considered to be that it is particularly easy to make the shape uniform in order to exhibit the effect that the existing water slightly swells with respect to the polymer in which the polar group is present.
[0118]
The toner of the present invention contains at least a resin and a colorant, but may contain a release agent, a charge control agent, or the like, which is a fixability improving agent, if necessary. Further, an external additive composed of inorganic fine particles or organic fine particles may be added to the toner particles containing the resin and the colorant as main components.
[0119]
As the colorant used in the toner of the present invention, carbon black, a magnetic material, a dye, a pigment, and the like can be arbitrarily used. Examples of the carbon black include channel black, furnace black, acetylene black, thermal black, and lamp black. used. Magnetic materials include ferromagnetic metals such as iron, nickel and cobalt, alloys containing these metals, compounds of ferromagnetic metals such as ferrite and magnetite, alloys that do not contain ferromagnetic metals but exhibit ferromagnetism by heat treatment, For example, a kind of alloy called Heusler alloy such as manganese-copper-aluminum, manganese-copper-tin, chromium dioxide, or the like can be used.
[0120]
As the dye, C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 122, C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93, 95 etc. can be used, and a mixture thereof can also be used. Examples of the pigment include C.I. I. Pigment Red 5, 48: 1, 53: 1, 57: 1, 122, 139, 144, 149, 166, 177, 178, 222, C.I. I. Pigment Orange 31 and 43, C.I. I. Pigment yellow 14, 17, 93, 94, 138, C.I. I. Pigment green 7, C.I. I. Pigment Blue 15: 3, 60, etc. can be used, and a mixture thereof can also be used. The number average primary particle size varies depending on the type, but is preferably about 10 to 200 nm.
[0121]
As a method for adding the colorant, the polymer particles prepared by the emulsion polymerization method are added at the stage of agglomerating by adding an aggregating agent, and the polymer is colored, or at the stage of polymerizing the monomer. The method of adding, polymerizing, and making it a colored particle etc. can be used. In addition, when adding a coloring agent in the step which prepares a polymer, it is preferable to use it, treating the surface with a coupling agent etc. so that radical polymerization property may not be inhibited.
[0122]
Further, a low molecular weight polypropylene (number average molecular weight = 1500 to 9000), a low molecular weight polyethylene, or the like as a fixing property improving agent may be added.
[0123]
Similarly, various known charge control agents and those that can be dispersed in water can be used. Specific examples include nigrosine dyes, naphthenic acid or higher fatty acid metal salts, alkoxylated amines, quaternary ammonium salt compounds, azo metal complexes, salicylic acid metal salts or metal complexes thereof.
[0124]
In addition, it is preferable that the number average primary particle diameter of these charge control agent and fixability improving agent particles is about 10 to 500 nm in a dispersed state.
[0125]
In a suspension polymerization method toner in which a toner component obtained by dispersing or dissolving a toner component such as a colorant in a so-called polymerizable monomer is suspended in an aqueous medium and then polymerized. The shape of the toner particles can be controlled by controlling the flow of the medium. That is, when a large amount of toner particles having a shape factor of 1.2 or more are formed, the flow of the medium in the reaction vessel is turbulent and the polymerization proceeds to exist in an aqueous medium in a suspended state. When the oil droplets gradually become polymerized, the oil droplets become soft particles. By colliding the particles, particle coalescence is promoted, and particles with an irregular shape are obtained. . When spherical toner particles having a shape factor smaller than 1.2 are formed, spherical particles can be obtained by using a laminar flow of the medium in the reaction vessel to avoid particle collision. By this method, the toner shape distribution can be controlled within the scope of the present invention. Hereinafter, the reaction apparatus preferably used in the present invention will be described.
[0126]
FIG. 3 is an explanatory view showing a reaction apparatus (stirring apparatus) having a generally used stirrer blade structure, wherein 2 is a stirrer tank, 3 is a rotating shaft, 4 is a stirrer blade, and 9 is a turbulent flow It is a forming member.
[0127]
In the suspension polymerization method, a turbulent flow can be formed by using a specific stirring blade, and the shape can be easily controlled. Although it is not clear as this reason, when the structure of the stirring blade 4 as shown in FIG. 3 is one stage, the flow of the medium formed in the stirring tank 2 is a wall surface from the lower part to the upper part of the stirring tank 2. It becomes only the flow that moves along. Therefore, conventionally, a turbulent flow is generally formed by arranging a turbulent flow forming member 9 such as a wall surface of the stirring tank 2 to increase the efficiency of stirring. However, in such an apparatus configuration, although the turbulent flow is partially formed, the fluid flow acts in the direction of stagnation due to the presence of the turbulent flow. I can't control it.
[0128]
A reactor equipped with a stirring blade that can be preferably used in the suspension polymerization method will be described with reference to the drawings.
[0129]
4 and 5 are a perspective view and a cross-sectional view showing an example of such a reaction apparatus, respectively. In the reaction apparatus shown in FIGS. 4 and 5, a rotating shaft 3 is vertically suspended at the center of a vertical cylindrical stirring tank 2 in which a jacket 1 for heat exchange is mounted on the outer periphery, and stirring is performed on the rotating shaft 3. A lower stirrer blade 40 disposed close to the bottom surface of the tank 2 and a stirrer blade 50 disposed further upward are provided. The upper agitating blade 50 is disposed with a crossing angle α preceding the agitating blade 40 located in the lower stage in the rotational direction. In the production of the toner of the present invention, the crossing angle α is preferably less than 90 degrees (°). The lower limit of the intersection angle α is not particularly limited, but is preferably about 5 ° or more, and more preferably 10 ° or more. When a three-stage stirring blade is provided, the crossing angle between adjacent stirring blades is preferably less than 90 degrees.
[0130]
By setting it as such a structure, a medium is first stirred by the stirring blade 50 arrange | positioned in the upper stage, and the flow to the lower side is formed. Next, the flow formed by the upper stirring blade 50 is further accelerated downward by the stirring blade 40 disposed in the lower stage, and a downward flow is separately formed in the stirring blade 50 itself, and the flow as a whole is increased. Presumed to be accelerated and proceed. As a result, a flow area having a large shear stress formed as a turbulent flow is formed, and it is estimated that the shape of the obtained toner particles can be controlled.
[0131]
4 and 5, arrows indicate the rotation direction, 7 is an upper material inlet, 8 is a lower material inlet, and 9 is a turbulent flow forming member for making stirring effective.
[0132]
Here, the shape of the stirring blade is not particularly limited, but it may be a rectangular plate, a notch in a part of the blade, one or more holes in the center, and a so-called slit. Can be used. Specific examples of these are shown in FIG. The stirring blade 5a shown in FIG. 12 (a) has no medium hole, the stirring blade 5b shown in FIG. 12 (b) has a large middle hole 6b in the center, and the stirring blade 5c shown in FIG. 12 (c). Has a horizontally elongated hole 6c (slit), and the stirring blade 5d shown in FIG. 4D has a vertically elongated hole 6d (slit). In addition, when a three-stage stirring blade is provided, the middle hole formed in the upper stirring blade and the middle hole formed in the lower stirring blade may be the same, even if they are different. There may be.
[0133]
6 to 10 are perspective views showing specific examples of a reactor equipped with a stirring blade that can be preferably used. In FIGS. 6 to 10, 1 is a jacket for heat exchange, and 2 is a stirring device. A tank, 3 is a rotating shaft, 7 is an upper material inlet, 8 is a lower material inlet, and 9 is a turbulent flow forming member.
[0134]
In the reaction apparatus shown in FIG. 6, a bent portion 411 is formed on the stirring blade 41, and a fin (projection) 511 is formed on the stirring blade 51.
[0135]
In addition, when the bending part is formed in the stirring blade, it is preferable that a bending angle is 5-45 degrees.
[0136]
In the stirring blade 42 constituting the reaction apparatus shown in FIG. 7, a slit 421 is formed, and a bent portion 422 and fins 423 are formed.
[0137]
In addition, the stirring blade 52 which comprises the said reaction apparatus has the shape similar to the stirring blade 50 which comprises the reaction apparatus shown in FIG.
[0138]
Bending portions 431 and fins 432 are formed on the stirring blade 43 constituting the reaction apparatus shown in FIG.
[0139]
In addition, the stirring blade 53 which comprises the said reaction apparatus has the shape similar to the stirring blade 50 which comprises the reaction apparatus shown in FIG.
[0140]
A bending portion 441 and fins 442 are formed on the stirring blade 44 constituting the reaction apparatus shown in FIG.
[0141]
In addition, the stirring blade 54 constituting the reaction apparatus has a middle hole portion 541 formed at the center.
[0142]
The reaction apparatus shown in FIG. 10 is provided with a three-stage stirring blade including a stirring blade 45 (lower stage), a stirring blade 55 (middle stage), and a stirring blade 65.
[0143]
A stirring blade having a structure having these bent portions and protrusions (fins) to the upper or lower portion effectively generates turbulent flow.
[0144]
The gap between the upper and lower stirring blades having the above-described configuration is not particularly limited, but it is preferable to have a gap at least between the stirring blades. Although the reason for this is not clear, it is considered that the stirring efficiency is improved because a medium flow is formed through the gap. However, the gap has a width of 0.5 to 50%, preferably 1 to 30%, with respect to the liquid surface height in the stationary state.
[0145]
Further, the size of the stirring blade is not particularly limited, but the total height of all the stirring blades is 50% to 100%, preferably 60% to 95% of the liquid surface height in the stationary state. is there.
[0146]
FIG. 11 shows an example of a reaction apparatus used when a laminar flow is formed in the suspension polymerization method. This reaction apparatus is characterized in that a turbulent flow forming member (an obstacle such as a baffle plate) is not provided.
[0147]
Stirring blades 46 and 56 constituting the reaction apparatus shown in FIG. 11 have the same shape and crossing angle α as the stirring blades 40 and 50 constituting the reaction apparatus shown in FIG. . In FIG. 11, 1 is a heat exchange jacket, 2 is a stirring tank, 3 is a rotating shaft, 7 is an upper material inlet, and 8 is a lower material inlet.
[0148]
In addition, as a reaction apparatus used when forming a laminar flow, it is not limited to what is shown by FIG.
[0149]
In addition, the shape of the stirring blades constituting such a reactor is not particularly limited as long as it does not form turbulent flow, but is preferably formed by a continuous surface such as a rectangular plate, and has a curved surface. You may do it.
[0150]
On the other hand, in a polymerization method toner that associates or fuses resin particles in an aqueous medium, by controlling the flow and temperature distribution of the medium in the reaction vessel at the fusing stage, and further in the shape control step after fusing. By controlling the heating temperature, the number of rotations of stirring, and the time, the shape distribution and shape of the entire toner can be arbitrarily changed.
[0151]
That is, in the polymerization method toner that associates or fuses the resin particles, the flow in the reaction apparatus is made into a laminar flow, and the agitation step and the agitation tank that can make the internal temperature distribution uniform are used. By controlling the temperature, the number of rotations, and the time in the shape control step, it is possible to form a toner having a desired shape factor and uniform shape distribution. The reason for this is that if the laminar flow is fused in the place where the laminar flow is formed, the particles that are agglomerated and fused (aggregated or agglomerated particles) are not subjected to strong stress, and the laminar flow in which the flow is accelerated It is estimated that this is because the shape distribution of the fused particles becomes uniform as a result of the uniform temperature distribution in the stirring tank. Further, the fused particles gradually become spherical by heating and stirring in the subsequent shape control step, and the shape of the toner particles can be arbitrarily controlled.
[0152]
As the stirring blade and the stirring tank used in the production of the polymerization toner for associating or fusing the resin particles, those similar to the case of forming a laminar flow in the suspension polymerization method described above can be used. 11 can be used. It is characterized in that no obstacle such as a baffle plate that forms a turbulent flow is provided in the stirring tank. As for the configuration of the stirring blade, like the stirring blade used in the above-described suspension polymerization method, the upper stirring blade is disposed with a crossing angle α preceding the lower stirring blade in the rotational direction. In addition, a multistage configuration is preferable.
[0153]
The shape of the stirring blade is not particularly limited as long as it can use the same laminar flow as in the above-described suspension polymerization method, as long as it does not form turbulent flow. Those formed by a continuous surface, such as a rectangular plate shape, are preferable, and may have a curved surface.
[0154]
In addition, the toner of the present invention can be more effective by adding and using fine particles such as inorganic fine particles and organic fine particles as external additives. The reason for this is presumed that the effect can be conspicuous because the burying and detachment of the external additive can be effectively suppressed.
[0155]
As the inorganic fine particles, inorganic oxide particles such as silica, titania, and alumina are preferably used, and these inorganic fine particles are preferably hydrophobized with a silane coupling agent or a titanium coupling agent. The degree of the hydrophobizing treatment is not particularly limited, but a methanol wettability of 40 to 95 is preferable. Methanol wettability is an evaluation of wettability to methanol. In this method, 0.2 g of inorganic fine particles to be measured is weighed and added to 50 ml of distilled water in a 200 ml beaker. Methanol is slowly dropped from a burette whose tip is immersed in a liquid, with slow stirring until the entire inorganic fine particles are wet. When the amount of methanol necessary to completely wet the inorganic fine particles is a (ml), the degree of hydrophobicity is calculated by the following formula.
[0156]
Hydrophobicity = (a / (a + 50)) × 100
The addition amount of the external additive is 0.1 to 5.0% by mass, preferably 0.5 to 4.0% by mass in the toner. In addition, various external additives may be used in combination.
[0157]
To the toner used in the present invention, a fatty acid metal salt may be added as an external additive. Fatty acids and their metal salts include undecyl acid, lauric acid, tridecyl acid, dodecyl acid, myristic acid, palmitic acid, pentadecylic acid, stearic acid, heptadecyl acid, arachidic acid, montanic acid, oleic acid, linoleic acid, arachidonic acid, etc. Examples of the metal salt thereof include salts with metals such as zinc, iron, magnesium, aluminum, calcium, sodium, and lithium. In the present invention, zinc stearate is particularly preferable.
[0158]
In order to prepare a two-component developer, a toner and a carrier are mixed. The toner concentration with respect to the developer is used by mixing 2 to 10% by mass.
[0159]
The developing method according to the present invention is not particularly limited. Even in a contact development method in which development is performed in a state where the surface of the photoreceptor and the developer layer are in contact with each other in the development area, the photoreceptor and the developer layer are kept in a non-contact state in the development area, and an alternating electric field or the like A non-contact developing method in which the toner is allowed to fly through the gap between the surface of the photoreceptor and the developer layer by the action described above may be used.
[0160]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, the aspect of this invention is not limited to this. In the text, “part” means “part by mass”.
[0161]
The following photoreceptors were prepared as the photoreceptors used in the present invention.
Manufacture of photoreceptor P1
30 g of polyamide resin Amilan CM-8000 (manufactured by Toray Industries, Inc.) was charged into a mixed solvent of 900 ml of methanol and 100 ml of 1-butanol and dissolved by heating at 50 ° C. This liquid was applied onto a cylindrical aluminum conductive support having an outer diameter of 80 mm and a length of 360 mm to form an intermediate layer having a thickness of 0.5 μm.
[0162]
Next, 10 g of silicone resin KR-5240 (manufactured by Shin-Etsu Chemical Co., Ltd.) is dissolved in 1000 ml of t-butyl acetate, and 10 g of Y-TiOPc (described in JP-A No. 64-17066, FIG. 1) is mixed therein and a sand mill is used. For 20 hours to obtain a charge generation layer coating solution. Using this solution, it was applied on the intermediate layer to form a charge generation layer having a thickness of 0.3 μm.
[0163]
Next, 150 g of CTM (T-1: N- (4-methylphenyl) -N- {4- (β-phenylstyryl) phenyl} -p-toluidine) and a polycarbonate resin TS-2050 having a viscosity average molecular weight of 50,000 ( 200 g of Teijin Chemicals Ltd.) was dissolved in 1000 ml of 1,2-dichloroethane to obtain a charge transport layer coating solution. Using this solution, the charge generation layer was coated on a circular slide hopper and then dried at 100 ° C. for 1 hour to form a charge transport layer having a thickness of 22 μm. Thus, a photoreceptor P1 composed of an intermediate layer, a charge generation layer, and a charge transport layer was obtained.
[0164]
A toner used in the present invention was prepared as follows.
Production of toner T1 (example of emulsion polymerization method)
Add 0.90 kg of sodium n-dodecyl sulfate and 10.0 l of pure water and dissolve with stirring. To this solution, 1.20 kg of Legal 330R (Cabot Black Carbon Black) was gradually added and stirred well for 1 hour, followed by continuous dispersion for 20 hours using a sand grinder (medium disperser). This is referred to as “colorant dispersion 1”. A solution composed of 0.055 kg of sodium dodecylbenzenesulfonate and 4.0 l of ion-exchanged water is referred to as “anionic surfactant solution A”.
[0165]
A solution composed of 0.014 kg of nonylphenol polyethylene oxide 10 mol adduct and 4.0 l of ion-exchanged water is referred to as “nonionic surfactant solution B”. A solution obtained by dissolving 223.8 g of potassium persulfate in 12.0 l of ion-exchanged water is referred to as “initiator solution C”.
[0166]
Into a 100-liter GL (glass lining) reaction kettle equipped with a temperature sensor, a cooling pipe, and a nitrogen introducing device, a WAX emulsion (a polypropylene emulsion having a number average molecular weight of 3000: number average primary particle size = 120 nm / solid content concentration = 29.9%) ) Put 3.41 kg, the total amount of “anionic surfactant solution A” and the total amount of “nonionic surfactant solution B”, and start stirring. Then, 44.0 l of ion exchange water is added.
[0167]
Heating was started and when the liquid temperature reached 75 ° C., the entire amount of “Initiator Solution C” was added dropwise. Thereafter, while controlling the liquid temperature to 75 ° C. ± 1 ° C., 12.1 kg of styrene, 2.88 kg of n-butyl acrylate, 1.04 kg of methacrylic acid, and 548 g of t-dodecyl mercaptan are added dropwise. After completion of the dropwise addition, the liquid temperature was raised to 80 ° C. ± 1 ° C. and stirring was performed for 6 hours. Next, the liquid temperature is cooled to 40 ° C. or lower, stirring is stopped, and the mixture is filtered through a pole filter, which is designated as “Latex (1) -A”.
[0168]
The glass transition temperature of the resin particles in the latex (1) -A was 57 ° C., the softening point was 121 ° C., the molecular weight distribution was weight average molecular weight = 17,000, and the weight average particle size was 120 nm.
[0169]
A solution obtained by dissolving 0.055 kg of sodium dodecylbenzenesulfonate in 4.0 l of ion-exchanged pure water is referred to as “anionic surfactant solution D”. Further, a solution obtained by dissolving 0.014 kg of nonylphenol polyethylene oxide 10 mol adduct in 4.0 l of ion-exchanged water is referred to as “nonionic surfactant solution E”.
[0170]
A solution obtained by dissolving 200.7 g of potassium persulfate (manufactured by Kanto Chemical Co., Ltd.) in 12.0 l of ion-exchanged water is referred to as “initiator solution F”.
[0171]
A WAL emulsion (a polypropylene emulsion with a number average molecular weight of 3000: number average primary particle size = 120 nm / solid content concentration of 29.9%) was added to a 100 l GL reaction kettle equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device and a comb baffle. .41 kg, the total amount of “anionic surfactant solution D” and the total amount of “nonionic surfactant solution E” are added, and stirring is started. Next, 44.0 l of ion exchange water is added. Heating is started, and when the liquid temperature reaches 70 ° C., “initiator solution F” is added. Next, a solution prepared by previously mixing 11.0 kg of styrene, 4.00 kg of n-butyl acrylate, 1.04 kg of methacrylic acid, and 9.02 g of t-dodecyl mercaptan is dropped. After completion of the dropwise addition, the liquid temperature was controlled at 72 ° C. ± 2 ° C., and the mixture was heated and stirred for 6 hours. Furthermore, the liquid temperature was raised to 80 ° C. ± 2 ° C., and the mixture was heated and stirred for 12 hours. The liquid temperature is cooled to 40 ° C. or lower and stirring is stopped. It filtered with the pole filter and this filtrate was set to "latex (1) -B".
[0172]
The glass transition temperature of the resin particles in latex {circle around (1)}-B was 58 ° C., the softening point was 132 ° C., the molecular weight distribution was weight average molecular weight = 245,000, and the weight average particle size was 110 nm.
[0173]
A solution obtained by dissolving 5.36 kg of sodium chloride as a salting-out agent in 20.0 l of ion-exchanged water is referred to as “sodium chloride solution G”.
[0174]
A solution obtained by dissolving 1.00 g of a fluorine-based nonionic surfactant in 1.00 l of ion-exchanged water is referred to as “nonionic surfactant solution H”.
[0175]
Latex prepared above in a 100 l SUS reaction kettle equipped with a temperature sensor, cooling pipe, nitrogen introduction device, particle size and shape monitoring device (reaction device having the configuration shown in FIG. 11, crossing angle α is 20 °). (1) -A = 20.0 kg, latex (1) -B = 5.2 kg, colorant dispersion 1 = 0.4 kg and ion-exchanged water 20.0 kg are added and stirred. Next, the mixture is heated to 40 ° C., and sodium chloride solution G, isopropanol (manufactured by Kanto Chemical Co.) 6.00 kg, and nonionic surfactant solution H are added in this order. Then, after standing for 10 minutes, the temperature rise was started, the temperature was raised to a liquid temperature of 85 ° C. in 60 minutes, and the particles were heated and stirred at 85 ± 2 ° C. for 0.5 to 3 hours while being salted out / fused. Grow. Next, 2.1 l of pure water is added to stop the particle size growth.
[0176]
The fused particle dispersion 5 prepared above was placed in a 5-liter reaction vessel equipped with a temperature sensor, a cooling pipe, a particle size and shape monitoring device (reaction device having the configuration shown in FIG. 11, crossing angle α was 20 °). 0.0 kg was added, and the shape was controlled by heating and stirring at a liquid temperature of 85 ° C. ± 2 ° C. for 0.5 to 15 hours. Then, it cools to 40 degrees C or less and stops stirring. Next, using a centrifugal separator, classification is performed in the liquid by a centrifugal sedimentation method, followed by filtration through a sieve having an opening of 45 μm. This filtrate is designated as an associated liquid (1). Subsequently, using a Nutsche, wet cake-like non-spherical particles were collected from the associated liquid (1) by filtration. Thereafter, it was washed with ion exchange water.
[0177]
The non-spherical particles were dried at a suction air temperature of 60 ° C. using a flash jet dryer and then dried at a temperature of 60 ° C. using a fluidized bed dryer. To 100 parts by mass of the obtained colored particles, 1 part by mass of silica fine particles and 0.1 part by mass of zinc stearate were externally added and mixed with a Henschel mixer to obtain a toner by an emulsion polymerization association method as shown in the table below. In the monitoring of the salting-out / fusion stage and the shape control process, by controlling the number of revolutions of stirring and the heating time, the coefficient of variation of the shape and the shape factor is controlled, and further the particle size and particle size distribution by subclassification in the liquid. The toner T1 was obtained by adjusting the coefficient of variation. The ratio of the shape factor 1.0 to 1.6 of toner 1 is 76.6%, the ratio of toner particles without corners is 53%, the number average particle diameter is 6.4 μm, m₁And m₂Was the sum (M) of 77.0%.
[0178]
Preparation of developer
Production of developer 1
0.4 parts of hydrophobic silica particles (R805: manufactured by Nippon Aerosil Co., Ltd.) having an average particle diameter of 12 nm and 0.6 parts of titania particles (T805: manufactured by Nippon Aerosil Co., Ltd.) as external additives are added to 100 parts of the toner T1. The mixture was mixed at a room temperature with a Henschel mixer at a peripheral speed of 40 (m / sec) with a stirring blade for 10 minutes to obtain a negatively chargeable toner. The fixing rate of this toner was 45%.
[0179]
Developer 1 having a toner concentration of 5% was prepared by mixing the above toner with a ferrite carrier coated with a silicone resin and having a volume average particle diameter of 60 μm.
[0180]
Example 1
Changes in free length and free end of thin metal plate and cleaning blade
Configuration: A thin metal plate member and a cleaning blade were bonded to a support member using a double-sided tape adhesive as shown in FIG. The combinations of the free length a of the cleaning blade, the free length b of the metal thin plate member, and the conditions for bonding the free length portion (adhesion) and the conditions for the free end (free end) not bonding were changed as shown in Table 1. .
[0181]
Other cleaning conditions
Cleaning blade: Thickness t₁: 2 mm, manufactured by Hokushin Kogyo Co., Ltd. (hardness 70 °, rebound resilience 60%)
Metal thin plate member: SUS304, thickness t₂: 0.05mm
Environmental conditions: normal temperature and normal humidity (20 ° C, 50%), low temperature and low humidity (10 ° C, 20%), high temperature and high humidity (30 ° C, 80%)
Cleaning blade contact angle: 20 °
Cleaning blade load (N / m): 25 N / m
Evaluation of cleaning performance.
[0182]
As shown in Table 1, the free length portions of the cleaning blade and the thin metal plate member are changed, and the Konica digital copying machine Konica 7050 (corona charging, laser exposure, reversal development, electrostatics) basically having the image forming process shown in FIG. Transfer, nail separation, and cleaning blades are used to evaluate toner slipping, blade turning, blade squealing, and image unevenness. For evaluation, original images with a pixel ratio of 7%, halftone photographic images, solid white images, and solid black images are divided into quarters, respectively, at room temperature and humidity (24 ° C, 60% RH). A copying experiment of 50 sheets of A4 paper / min was conducted continuously for 90 minutes. However, in order to familiarize the photoconductor and the cleaning blade before the start of the evaluation, setting powder was applied to the photoconductor and the cleaning blade, and the photoconductor was rotated for 1 minute. Other conditions for image evaluation are described below. The evaluation results are shown in Table 1.
[0183]
Other evaluation conditions
The other evaluation conditions using 7050 were set to the following conditions.
[0184]
Photoconductor: P1
Developer: 1 (toner: T1)
Charging conditions
Charger: Scorotron charger, initial charge potential of -750V
Exposure conditions
Set the exposure amount so that the potential of the exposed area is -50V.
[0185]
Development conditions
DC bias; -550V
Dsd; 550 μm
Developer layer regulation; edge cut method
Developer layer thickness: 700 μm
Development sleeve diameter: 40 mm
Transcription conditions
Transfer pole; corona charging method, transfer dummy current value: 45 μA
Evaluation items and evaluation criteria
Toner slipping through (Suri Nuke in the table)
○: No development toner slips
Δ: 0% or less and less than 20% of developed toner
×: 20% or more and less than 50% of developed toner slipped
XX: More than 50% of developed toner slips through
Blade turning (Mekle in the table)
Displayed with or without blade turning.
[0186]
Blade squeal
Abnormal noise generated due to abnormal friction between the cleaning blade and the photosensitive member was referred to as blade noise, and the presence or absence of occurrence of this abnormal noise was evaluated.
[0187]
Image quality evaluation (with / without image unevenness)
The occurrence of image unevenness was evaluated in the above-mentioned 90-minute continuous copying halftone photographic image.
[0188]
[Table 1]

[0189]
As is clear from Table 1, in the case of the present invention in which the free thin portions of the thin metal plate member and the cleaning blade are free ends, normal temperature and normal humidity (20 ° C., 50%), low temperature and low humidity (10 ° C., 20%) ), In any environment of high temperature and high humidity (30 ° C., 80%), it exhibits good cleaning characteristics for all evaluation items such as blade turning and toner slipping, while the free length portion is a free end. In cases other than the present invention, good cleaning characteristics are exhibited under normal temperature and normal humidity conditions, but it is found that blade turning and toner slipping are likely to occur under low temperature and low humidity, or high temperature and high humidity. .
[0190]
【The invention's effect】
As is clear from the above-described embodiment, the use of a cleaning device having a cleaning blade having a thin metal plate bonded to each other under the conditions of the present invention eliminates the occurrence of blade turning or toner slipping of residual toner on the organic photoreceptor. Can be cleaned. The present invention can also provide an image forming method and an image forming apparatus using the cleaning device.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an overall configuration of an image forming apparatus according to the present invention.
FIG. 2 is a configuration diagram of a cleaning device using the cleaning blade of the present invention.
FIG. 3 is an explanatory diagram showing a reaction apparatus having a single-stage stirring blade.
FIG. 4 is a perspective view showing an example of a reactor equipped with a stirring blade that can be preferably used.
FIG. 5 is a cross-sectional view of the reaction apparatus shown in FIG.
FIG. 6 is a perspective view showing a specific example of a reactor equipped with a stirring blade that can be preferably used.
FIG. 7 is a perspective view showing a specific example of a reactor equipped with a stirring blade that can be preferably used.
FIG. 8 is a perspective view showing a specific example of a reactor equipped with a stirring blade that can be preferably used.
FIG. 9 is a perspective view showing a specific example of a reactor equipped with a stirring blade that can be preferably used.
FIG. 10 is a perspective view showing a specific example of a reactor equipped with a stirring blade that can be preferably used.
FIG. 11 is a perspective view showing an example of a reaction apparatus used when a laminar flow is formed.
FIG. 12 is a schematic view showing a specific example of the shape of a stirring blade.
FIGS. 13A and 13B are explanatory views showing projected images of toner particles having no corners, and FIGS. 13B and 13C are explanatory views showing projected images of toner particles having corners. FIGS.
[Explanation of symbols]
1 Heat exchange jacket
2 Mixing tank
3 Rotating shaft
4 Stirring blade
40 stirring blade
411 bending part
421 slit
423 Fin
50 stirring blade
541 Medium hole
55 Stirring blade
5a, 5b, 5c, 5d stirring blade
6b, 6c, 6d
7 Upper material inlet
8 Lower material inlet
9 Turbulence forming member
α crossing angle
121 photoconductor
122 Charger
123 Developer
124 Transfer device
125 separator
126 Cleaning device
126A Cleaning blade
126B Thin metal plate member
127 PCL (precharge lamp)
130 Exposure optical system
191 Support member
a Free length of the cleaning blade
b Free length of sheet metal member
t₁  Cleaning blade thickness
t₂  Metal sheet thickness

Claims (7)

And an organic photoreceptor, an image forming apparatus including a cleaning device having a cleaning blade and the sheet metal held by the holding member, containing toner an electrostatic latent image formed on the organic photoreceptor development In the image forming apparatus in which the toner image developed by the agent is transferred to the transfer material from the organic photoreceptor to the transfer material, and then the toner remaining on the organic photoreceptor is removed by the cleaning blade.
The cleaning blade and the metal plate member have a boundary surface that adheres to each other and a boundary surface that does not adhere to each other,
The cleaning blade is bonded to the said sheet metal member on the organic photoreceptor in the surface opposite to the surface contacting,
And the free length portion of said cleaning blade and said sheet metal member is not being held by the holding member, an image forming apparatus which is a free end having a boundary surface that does not adhere to one another. 2. The step according to claim 1, wherein a step is provided between the tip of the cleaning blade and the tip of the metal thin plate member, and the step is such that the metal thin plate member is positioned farther from the organic photoreceptor. Image forming apparatus. The electrostatic latent image formed on the organic photoconductor is developed with a developer containing toner, and the toner image visualized by the development is transferred from the organic photoconductor to a transfer material, and then on the organic photoconductor. In the image forming method of removing the residual toner by a cleaning device having a cleaning blade and a metal thin plate held by a holding member,
The cleaning blade and the metal plate member have a boundary surface that adheres to each other and a boundary surface that does not adhere to each other,
The cleaning blade adheres to the metal thin plate member at the boundary surface opposite to the surface in contact with the organic photoreceptor,
And the free length portion of said cleaning blade and said sheet metal member is not being held by the holding member, an image forming method comprising the free end der Rukoto having an interface that does not adhere to one another. 3. The toner according to claim 1, wherein a toner having a variation coefficient of a shape factor of toner particles of 16% or less and a number variation coefficient in a number particle size distribution of the toner particles of 27% or less is used as the toner. The image forming apparatus described in 1. The toner, image forming apparatus according to claim 4 in which the shape factor is characterized by using a toner you containing toner particles 65 number% or more in the range of 1.2 to 1.6. 6. The image forming apparatus according to claim 5 , wherein a toner containing 50 % by number or more of toner particles having no corners is used as the toner. Claims wherein the organic photosensitive member has a photosensitive layer provided comprising structure on a conductive support, and a surface layer of the photosensitive layer is characterized that you containing polycarbonate having a viscosity average molecular weight from 40,000 to 200,000 Item 7. The image forming apparatus according to any one of Items 4 to 6 .

Images