JP2005091692A - Lubricant applying means, process cartridge using the same, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the dependence of physical properties of a brush in a lubricant application means by a relatively simple and low-cost configuration, and to ensure control and uniformity of the amount of lubricant applied to a photoreceptor surface. Provided is a lubricant application means.
SOLUTION: A rotating photosensitive belt 2 is arranged in contact with the photosensitive belt 2, and a rotatable brush for applying a lubricant to the photosensitive belt 2 is provided, and the brush is always in contact with the lubricant. In the lubricant application means 20, the rotatable application brush 202 is controlled by switching ON / OFF timing of rotation.
[Selection] Figure 2

Description

  The present invention relates to a lubricant application means for applying a lubricant to an image carrier in image formation by an electrostatic copying process such as a copying machine, a facsimile machine, a printer, etc., a process cartridge using the same, and an image forming apparatus.

  The present invention provides an image carrier on which a toner image is formed while being rotated, a transfer device that transfers the toner image to a transfer material, and a transfer residual toner that adheres to the surface of the image carrier after the toner image is transferred. An image comprising a cleaning member that removes and cleans the surface of the image carrier, and a lubricant application member that has a brush that contacts the surface of the image carrier and that applies a lubricant to the surface of the image carrier while being rotated. Regarding an image forming apparatus, an image forming apparatus of the above-described type configured as an electronic copying machine, a printer, a facsimile machine, or a multifunction machine having at least two of these functions has been conventionally known (for example, see Patent Document 1). According to this type of image forming apparatus, since the lubricant is applied to the surface of the image carrier, the coefficient of friction with respect to the toner on the surface of the image carrier can be reduced, whereby the toner formed on the surface of the image carrier. It is possible to suppress the occurrence of transfer failure when the image is transferred to the transfer material, and to improve the image quality of the transferred toner image. In particular, it is possible to suppress the occurrence of a character part dropout phenomenon in which a part of a character image is lacking in a worm-like shape and improve the image quality. Further, it has the effect of preventing toner filming on the surface of the image carrier and suppressing the abrasion of the surface layer, and contributes to the life of the image carrier on the hard surface.

Further, in recent years, the production of a toner having a small particle size and a narrow particle size distribution is difficult by a pulverization method, and usually a polymerization method is used. The toner is formed into a sphere (true sphere) by this polymerization method. While the transfer efficiency from the carrier to the transfer material has been remarkably improved, the toner on the image carrier remaining as a transfer residue is difficult to peel off, and an effective means for reducing the coefficient of friction of the image carrier surface is an image. It is also very effective for maintaining the performance of the carrier cleaning process.
However, when a lubricant is applied to the surface of the image carrier, the coefficient of friction with respect to the toner on the surface decreases, so if the amount of lubricant applied to the surface of the image carrier becomes non-uniform, the unevenness of the application causes the image carrier to become uneven. The toner adhesion amount of the toner image formed on the surface becomes non-uniform, uneven density occurs in the toner image, and the image quality deteriorates. This is because the amount of toner adhering to the surface of the image carrier with a large amount of lubricant applied decreases, and conversely, a large amount of toner adheres to the portion with a small amount of lubricant applied. Unevenness occurs. In particular, uneven density tends to occur in a low-density toner image.

Specifically, when the static friction coefficient of the image carrier is too low, image omission (a part of dots, characters, lines, etc. is lost) occurs in the image formed on the image carrier. In the contact development method, toner is brought into contact with the image carrier and moved to the surface of the image carrier by an electric field or an adhesion force to the surface of the image carrier. At this time, in the case of one-component development, the roller is brought into direct contact with the image carrier in the case of two-component development. Therefore, if the static friction coefficient on the surface of the image carrier is too low, the roller is formed on the image carrier. The toner image is easily scraped off by the roller and the carrier.
Also, an image carrier having a large outer periphery is less advantageous than uniform ones because the number of coatings is less for the same length in the circumferential direction, which is disadvantageous for uniform application in controlling the coating amount of the entire image carrier.

JP 56-154778 A

  Therefore, various configurations have conventionally been proposed to ensure the control and uniformity of the amount of lubricant applied to the surface of the image carrier, or the material of the brush in the lubricant application means has been studied, but image formation The configuration of the apparatus is complicated, and the cost increases.

  Therefore, the present invention has been made in view of the above-described problems, and the problem is that the dependency of the physical properties of the brush in the lubricant application means is reduced by a relatively simple and low-cost configuration, and the surface of the image carrier is reduced. The present invention provides a lubricant application means capable of ensuring the control and uniformity of the amount of lubricant applied to the film, a process cartridge using the same, and an image forming apparatus.

The features of the present invention, which is a means for solving the above problems, are listed below.
The lubricant application means of the present invention comprises a rotating image carrier and a rotatable brush which is disposed in contact with the image carrier and applies a lubricant to the image carrier, and the brush comprises the lubricant and the lubricant. In the lubricant application means that is always in contact, the rotatable brush is controlled by switching the ON / OFF timing of rotation.
Further, the lubricant applying means of the present invention is further configured such that the rotatable brush has a rotation ON / OFF timing of a time T2 that does not become an integer ratio of at least a time T1 required for one rotation of the image carrier. It is characterized by being controlled at a duty ratio of%.
The lubricant applying means of the present invention is further characterized in that the rotating operation of the rotatable brush is turned off at least when the image carrier is not rotating.

The process cartridge of the present invention includes at least a rotating image carrier and a rotatable brush that is disposed in contact with the image carrier and applies a lubricant to the image carrier, and the brush is the lubricant and the lubricant. In a process cartridge comprising a lubricant application means that is always in contact, the rotatable brush is controlled by switching the ON / OFF timing of rotation.
The process cartridge according to the present invention further includes a lubricant application unit according to claim 2 or 3.

The image forming apparatus of the present invention includes a rotating image carrier and a rotatable brush that is disposed in contact with the image carrier and applies a lubricant to the image carrier, and the brush is always in contact with the lubricant. In the image forming apparatus having the lubricant application means in contact, the circumference of the image carrier is not less than the maximum image length of the image forming apparatus, and the ON / OFF timing of rotation of the rotatable brush is arbitrarily set It has the control means to switch, It is characterized by the above-mentioned.
Further, in the image forming apparatus of the present invention, the ON / OFF timing of the rotation of the rotatable brush is set to a time T2 that is not at least an integer ratio of the time T1 required for one rotation of the image carrier. And a means for variably controlling with the duty ratio.
The image forming apparatus of the present invention is further characterized in that the rotation operation of the rotatable brush is turned off at least when the image carrier is not rotating.
Further, in the image forming apparatus of the present invention, the toner used in the developing unit has a volume average particle diameter of 3 to 8 μm, and a ratio between the volume average particle diameter (Dv) and the number average particle diameter (Dn) ( Dv / Dn) is in the range of 1.00 to 1.40.
In the image forming apparatus of the present invention, it is further preferable that the toner used in the developing unit has a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180. Features.
Further, in the image forming apparatus of the present invention, the toner used in the developing unit further includes at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent dispersed in an organic solvent. It is a toner obtained by crosslinking and / or stretching reaction of the toner material solution thus prepared in an aqueous medium.
The image forming apparatus of the present invention is further characterized in that the toner used in the developing means has a substantially spherical shape.
Furthermore, the image forming apparatus of the present invention is further characterized in that the image forming apparatus includes the process cartridge according to claim 4 or 5.

  By the means for solving the above, the lubricant applying means of the present invention, the process cartridge and the image forming apparatus using the same, reduce the dependence of the physical properties of the brush on the lubricant applying means, and the lubricant on the surface of the image carrier. The application amount can be controlled to an appropriate value, and the effect of excessive application of the lubricant on a specific portion of the image carrier can be prevented.

The best mode for carrying out the present invention will be described below with reference to the drawings. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode of the present invention, and does not limit the scope of the claims.
FIG. 1 shows a configuration of a main part of an image forming apparatus according to an embodiment of the present invention.
As shown in FIG. 1, there are a charging device 4, an exposure device 6, a developing device 8, a fixing device 9, a transfer device 10, a lubricant applying means 20, and a cleaning device 14 around a photosensitive belt 2 as an image carrier. The image forming processes such as charging, exposure, development, transfer, cleaning, and charge removal are executed as the photosensitive belt 2 rotates in the direction of the arrow. By exposure by the exposure device 6, an electrostatic latent image of a target image is formed on the photosensitive belt 2, and this electrostatic latent image is visualized as a toner image by the developing device 8. Four developing devices 8 of different colors are provided around the photoconductor 30, and the toner images of the respective colors are superimposed and transferred onto an intermediate transfer belt 101 as an image carrier, and a predetermined roller is used. The transfer roller 102 collectively transfers the recording medium P that is sent at the timing. A cleaning brush 103 for cleaning the toner remaining on the intermediate transfer belt 101 is provided, and a similar problem due to wear occurs even in such a configuration. In order to cope with this, the lubricant applying means 20 may be provided on the intermediate transfer belt 101.

The recording medium P to which the toner image has been transferred is sent to the fixing device 9, where the toner image is fixed on the recording medium P as a permanent image by heat and pressure. The toner remaining on the photosensitive belt 2 is scraped off by the cleaning device 14, and the residual charge is removed by a static eliminator constituted by a static elimination lamp such as an EL.
FIG. 2 is a schematic diagram showing the configuration of the lubricant application means. The lubricant application unit 20 includes a case fixed to the apparatus main body, a lubricant 201 movably accommodated in the case, and scrapes the lubricant 201 in contact with the lubricant 201 to remove the surface of the photoreceptor belt 2. It is mainly comprised from the application brush 202 supplied to the. The lubricant 201 is formed in a rectangular parallelepiped shape, and the application brush 202 has a shape extending in the axial direction of the photosensitive belt 2. The lubricant 201 is urged by a spring (not shown) against the application brush 202 so that almost all of the lubricant 201 can be used up. Since the lubricant 201 is a consumable item, its thickness decreases with time, but since it is pressurized by a spring, it always contacts the application brush 202.

As shown in FIG. 2 as an example, the lubricant application brush 202 has a large number of brushes provided on the outer peripheral surface thereof in the width direction of the photosensitive belt 2, that is, the central axis extending long in the axial direction. . For example, it is configured by planting a brush on a base cloth (not shown) and fixing the base cloth to the outer peripheral surface of the central axis. The tip of the application brush 202 is in contact with the surface of the photoreceptor belt 2 over almost the entire width. The rotation shaft extends in a direction perpendicular to the paper surface of FIGS. 1 and 2 at a certain interval from the surface of the photoreceptor belt 2 and rotates to the front and rear side walls of the cleaning device 14 constituting an example of the support member. It is supported freely and is driven to rotate in an appropriate direction, in the example shown in the figure, in the clockwise direction (arrow C direction) by a driving device (not shown). In the contact portion between the coating brush 202 and the photosensitive belt 2, the rotation direction is set in such a direction that the two move in opposite directions.
When the application brush 202 rotating in the direction of arrow C contacts the solid lubricant 201, the lubricant 201 is scraped off little by little from the solid lubricant 201. The lubricant 201 thus transferred to the application brush 202 is applied to the surface of the photoreceptor belt 2 that is driven in the direction of arrow A while being in contact with the application brush 202.

Moreover, as the lubricant of the lubricant 201 used in the lubricant applying means 20, a metal soap such as low molecular weight polytetrafluoroethylene (hereinafter referred to as “low molecular weight PTFE”), a fatty acid metal salt, or the like is used.
Low molecular weight PTFE refers to PTFE having an average molecular weight of several hundreds of thousands or less, but is manufactured by controlling the molecular weight by a polymerization method, a radiolysis method, a thermal decomposition method, etc., and the average molecular weight is kept low. Yes. By keeping the average molecular weight low, the effect of the lubricant is exhibited.
In addition, as metal soap, zinc stearate, barium stearate, lead stearate, iron stearate, nickel stearate, cobalt stearate, copper stearate, strontium stearate, calcium stearate, cadmium stearate, magnesium stearate, Zinc oleate, manganese oleate, iron oleate, cobalt oleate, lead oleate, magnesium oleate, copper oleate, palmitic acid, cobalt zinc palmitate, copper palmitate, magnesium palmitate, aluminum palmitate, palmitate List relatively higher fatty acids such as calcium, lead caprylate, lead caproate, zinc linolenate, cobalt linolenate, calcium linolenate, and cadmium ricolinolenate. It can be.
Natural waxes such as carnauba wax can also be used.

Here, the effect of the lubricant 201 can be evaluated as the coefficient of static friction μs of the applied photoreceptor belt 2. As the static friction coefficient μs, data measured by the Euler belt method is used. FIG. 3 is a diagram illustrating the Euler belt method. As shown in FIG. 3, a photosensitive belt of a drum composed of a photoconductor for measurement is fixed to a pedestal, and a fine paper having a thickness of 89 μm cut to a width of 30 mm and a length of, for example, 297 mm [TYPE 6200 manufactured by Ricoh Co. Paper, A4T eyes] is wound around the circumferential surface of the photoreceptor belt over an angle of 90 °, and a weight of 0.98 N (100 g weight) is applied to one end of the paper as a load W via a thread with negligible weight. Attach a digital push-pull gauge for weight measurement to the other end through a thread that can ignore weight. Slowly pull the digital push-pull gauge placed on the table in the direction of arrow A, read the weight F (N) when the paper starts to slide on the photosensitive belt, and calculate it using the following equation (1). .
μs = 2 / π × 1n (F / w) (1)
(However, μs: Coefficient of static friction, F: Measurement value, w: Load)

  The effect of obtaining a static friction coefficient μs on the surface of the photoreceptor belt 2 is 0.4 or less by the Euler belt method from the viewpoint of wear. The coefficient of static friction of the photosensitive belt 2 is preferably set to 0.4 or less, and an example of the implementation is the configuration of the lubricant application unit 20. However, when not only maintaining 0.4 or less at all times but also controlling a certain amount of wear, it may temporarily exceed 0.4 for an arbitrary time. Further, it is more preferable to control to 0.1 to 0.3 as a region having a higher effect on wear. In this case, the amount of wear is further reduced. However, it has been experimentally confirmed that when the coefficient of static friction is less than 0.1, image defects occur due to the influence of discharge products and the like, and the coefficient of static friction should not be reduced to less than 0.1. Is desirable. However, since these numerical values vary depending on environmental conditions and the like, a value less than 0.1 is not always defective.

FIG. 4 is a timing chart of a motor that is a drive source of the lubricant application brush and a clutch for transmitting rotation from the drive source to the lubricant application brush.
The clutch ON means that the lubricant 201 is applied onto the surface of the photoreceptor belt 2. When the lubricant 201 is applied, the coefficient of friction with respect to the toner on the surface thereof is reduced. Therefore, if the amount of the lubricant 201 applied to the surface of the photoreceptor belt 2 becomes non-uniform, unevenness of the application causes unevenness on the surface of the photoreceptor belt 2 body. The amount of toner adhering to the formed toner image becomes non-uniform, causing density unevenness in the toner image and degrading the image quality. On the surface of the image carrier where the amount of lubricant 201 applied is large, the amount of toner attached decreases, and conversely, a large amount of toner adheres to the portion where the amount of lubricant 201 applied is small, resulting in uneven density on the toner image. Will occur. In particular, uneven density tends to occur in a low-density toner image. Accordingly, since at least the rotation of the application brush 202 of the lubricant 201 needs to be turned off when the photosensitive belt 2 is stopped, in this embodiment, the drive source of the application brush 202 of the lubricant 201 is a developing motor related to image formation. Of course, the developing motor is stopped when the photosensitive belt 2 is not driven. In this way, by controlling ON / OFF, non-uniformity of the lubricant 201 of the photosensitive belt 2 is prevented. Further, by making the circumferential length of the photosensitive belt 2 the maximum image length, similarly, the unevenness of the lubricant 201 of the photosensitive belt 2 is prevented. If the circumferential length of the photosensitive belt 2 is shorter than the maximum image length, the same portion of the photosensitive belt 2 is repeatedly used during the formation of one image, so that uneven coating of the lubricant 201 causes unevenness on the surface of the photosensitive belt 2 body. The amount of toner adhering to the formed toner image becomes non-uniform, causing density unevenness in the toner image and degrading the image quality. Therefore, the deterioration of the image quality is prevented by making the peripheral length of the photosensitive belt 2 longer than the maximum image length.

Further, it is variably controlled at a duty ratio where a time T2 that does not become at least an integer ratio of the time T1 required for one rotation of the photosensitive belt 2 is 100%. For example, the maximum image A3 is 297 mm wide × 420 mm long, the circumferential length of the photosensitive belt 2 is 527.79 mm, and the process linear velocity is set to 178 mm / sec. As shown in FIG. 3, the clutch timing chart is ON time, and the symbol X is 3.855 sec (the time required for the photosensitive belt 2 to make one revolution is 3.855 seconds). (T1) is a display when 2.965 sec) is 100%.
ON time: X can be varied from 0 to 100%. For example, if X = 100%, the clutch is ON and the coating brush 202 rotates. If X = 60%, the ON time is 3.855 × 0. .6 = 2.313 sec and OFF time is 3.855 × 0.4 = 1.542 sec. By setting T2 to a time that does not become an integer ratio with respect to the time required for the circumference of the photosensitive belt 21, it is possible to apply at random to the entire circumference without applying a specific portion in the circumferential direction. The time T2 is twice as long as the time required for the photosensitive belt 2 is 1.3 laps, as well as 1.1, 1.7, and 1.9 laps. A higher effect can be obtained by setting the time corresponding to the circumference that does not become an integer even if it is 4 times or 5 times.

塗布ブラシ２０２のブラシ材質としては、Ａ：炭素含有アクリル繊維、Ｂ：ＰＥＴ、Ｃ：塩化ビニルアクリルブロック共重合体、Ｄ：ナイロン、Ｅ：アクリルである。
表１に示すように、ＯＮタイム：Ｘを可変設定することによって、潤滑剤２０１の塗布ムラによる画像濃度ムラの発生を抑えることができ、ブラシ材質に依存することなく、潤滑剤２０１の塗布量及び塗布均一性が確保できることがわかる。尚、ブラシＤのムラは周方向（塗布のＯＮ／ＯＦＦによる）のムラでなく、回転軸方向（ブラシ固有）のムラである。 In the image forming apparatus of the present invention described above, the ON time: X value was varied, and halftone unevenness, missing dots, and filming on the photosensitive belt 2 were evaluated. The results are shown in Table 1.

The brush material of the application brush 202 is A: carbon-containing acrylic fiber, B: PET, C: vinyl chloride acrylic block copolymer, D: nylon, E: acrylic.
As shown in Table 1, by variably setting the ON time: X, occurrence of image density unevenness due to uneven application of the lubricant 201 can be suppressed, and the amount of application of the lubricant 201 is independent of the brush material. It can be seen that the coating uniformity can be secured. The unevenness of the brush D is not uneven in the circumferential direction (due to ON / OFF of application) but is uneven in the rotation axis direction (specific to the brush).

Here, the following toner is used.
The volume average particle diameter Dv of the toner is preferably in the range of 3 to 8 μm. Since the smaller one can improve the fine line reproducibility, toner of 8 μm or less is used at most. However, since the developing property and the cleaning property are lowered when the particle size is small, at least 3 μm is preferable. Further, if the particle size is less than 3 μm, the toner having a small particle diameter that is difficult to be developed on the surface of the carrier or the developing roller increases. This is not preferable because an abnormal image such as fogging is formed. If the thickness is less than 3 μm, the effect of polishing the lubricant 201 is small, so that the coating unevenness of the lubricant 201 increases.
The particle size distribution represented by the ratio (Dv / Dn) of the volume average particle size Dv to the number average particle size Dn is preferably in the range of 1.00 to 1.40. By sharpening the particle size distribution, the toner charge amount distribution can be made uniform. When Dv / Dn exceeds 1.40, it becomes difficult to obtain a high-quality image because the toner charge amount distribution becomes wide. The particle size of the toner is 50,000 by using a Coulter Counter Multisizer (manufactured by Coulter Co., Ltd.) and selecting an aperture having a measurement hole size of 50 μm corresponding to the particle size of the toner to be measured. It is obtained by measuring the average particle size of the particles.

The toner preferably has a shape factor SF-1 in the range of 100 or more and 180 or less and a shape factor SF-2 in the range of 100 or more and 180 or less in the circularity. 5A and 5B are diagrams schematically illustrating the shape of the toner. FIG. 5A is a diagram for explaining the shape factor SF-1, and FIG. 5B is a diagram for explaining the shape factor SF-2. The shape factor SF-1 indicates the ratio of the roundness of the toner shape and is represented by the following formula (1). This is a value obtained by dividing the square of the maximum length MXLNG of the shape formed by projecting the toner on a two-dimensional plane by the figure area AREA and multiplying by 100π / 4.
SF-1 = {(MXLNG) ² / AREA} × (100π / 4) (1)
When the value of SF-1 is 100, the shape of the toner becomes a true sphere, and becomes larger as the value of SF-1 increases.
The shape factor SF-2 indicates the ratio of the unevenness of the toner shape, and is represented by the following formula (2). A value obtained by dividing the square of the perimeter PERI of the figure formed by projecting the toner on the two-dimensional plane by the figure area AREA and multiplying by 100π / 4.
SF-2 = {(PERI) ² / AREA} × (100π / 4) …… Equation (2)
When the value of SF-2 is 100, there is no unevenness on the toner surface, and as the value of SF-2 increases, the unevenness of the toner surface becomes more prominent.

As SF-1 and SF-2 approach 100, the toner on the photoreceptor belt 2 is likely to roll, and thus cleaning failure is likely to occur. However, by reducing the friction coefficient of the photoreceptor belt 2, this can be achieved. It corresponds to. If SF-1 and SF-2 exceed 180, the toner charge amount distribution is widened, and the character dust and background fog increase, resulting in a decrease in image authority. Further, development and transfer are easily affected by air resistance or the like, and movement along an electric field is difficult, and high-definition image reproducibility is lowered. It is preferable that SF-1 and SF-2 do not exceed 180.
Specifically, the shape factor is measured by taking a photograph of the toner with a scanning electron microscope (S-800: manufactured by Hitachi, Ltd.), introducing it into an image analyzer (LUSEX 3: manufactured by Nireco) and analyzing it. Calculated.

Further, the toner used in this image forming apparatus may be substantially spherical. 6A and 6B are schematic views showing the outer shape of the toner, where FIG. 6A is an appearance of the toner, and FIG. 6B is a cross-sectional view of the toner. In FIG. 6A, the X axis represents the longest axis r1 of the longest axis of the toner, the Y axis represents the shortest axis r2 of the next longest axis, and the Z axis represents the thickness r3 of the shortest axis. ≧ Short axis r2 ≧ Thickness r3
The toner has a major axis / minor axis ratio (r2 / r1) of 0.5 to 1.0 and a thickness / minor axis ratio (r3 / r2) of 0.7 to 1.0. It has a substantially spherical shape. When the ratio of the major axis to the minor axis (r2 / r1) is less than 0.5, the charge amount distribution becomes wide because it approaches an indefinite shape.
When the ratio of the thickness to the short axis (r3 / r2) is less than 0.7, the charge amount distribution becomes wide because the shape approaches an indefinite shape. In particular, when the ratio of the thickness to the short axis (r3 / r2) is 1.0, the charge amount distribution becomes narrow because of the substantially spherical shape.
The size of the toner so far was measured with a scanning electron microscope (SEM) while changing the angle of the field of view and observing in situ.
The shape of the toner can be controlled by the manufacturing method. For example, the toner by the dry pulverization method has an irregular shape in which the toner surface is uneven and the toner shape is not constant. Even this dry pulverized toner can be made into a nearly spherical toner by applying mechanical or thermal treatment. In many cases, a toner produced by forming droplets by a suspension polymerization method or an emulsion polymerization method has a smooth surface and a nearly spherical shape. Moreover, it can be made into an ellipse by stirring in the middle of the reaction in a solvent and applying a shearing force.

In addition, as such a substantially spherical toner, a toner composition containing a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent in an aqueous medium in the presence of fine resin particles. A toner that undergoes crosslinking and / or elongation reaction is preferred.
Hereinafter, the constituent material of the toner and a suitable manufacturing method will be described.
(polyester)
The polyester is obtained by a polycondensation reaction between a polyhydric alcohol compound and a polycarboxylic acid compound.
Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable. Examples of the dihydric alcohol (DIO) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. The trihydric or higher polyhydric alcohol (TO) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

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

The ratio of the polyhydric alcohol (PO) to the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Is 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.
The polycondensation reaction between a polyhydric alcohol (PO) and a polycarboxylic acid (PC) is carried out in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and heated to 150 to 280 ° C. while reducing the pressure as necessary. The produced water is distilled off to obtain a polyester having a hydroxyl group. The hydroxyl value of the polyester is preferably 5 or more, and the acid value of the polyester is usually 1 to 30, preferably 5 to 20. By giving an acid value, it tends to be negatively charged, and furthermore, when fixing to a recording paper, the affinity between the recording paper and the toner is good and the low-temperature fixability is improved. However, when the acid value exceeds 30, there is a tendency to deteriorate with respect to the stability of charging, particularly environmental fluctuation.
The weight average molecular weight is 10,000 to 400,000, preferably 20,000 to 200,000. A weight average molecular weight of less than 10,000 is not preferable because offset resistance deteriorates. On the other hand, if it exceeds 400,000, the low-temperature fixability is deteriorated.

In addition to the unmodified polyester obtained by the above polycondensation reaction, the polyester preferably contains a urea-modified polyester. The urea-modified polyester is obtained by reacting a terminal carboxyl group or hydroxyl group of the polyester obtained by the above polycondensation reaction with a polyvalent isocyanate compound (PIC) to obtain a polyester prepolymer (A) having an isocyanate group. It is obtained by cross-linking and / or extending the molecular chain by the reaction of the amine with amines.
Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.) Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; Those blocked with caprolactam or the like; and combinations of two or more of these.
The ratio of the polyvalent isocyanate compound (PIC) is usually 5/1 to 1/1, preferably as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. When the molar ratio of [NCO] is less than 1, when a urea-modified polyester is used, the urea content in the ester is lowered and hot offset resistance is deteriorated.
The content of the polyvalent isocyanate compound (PIC) component in the polyester prepolymer (A) having an isocyanate group is usually 0.5 to 40 wt%, preferably 1 to 30 wt%, more preferably 2 to 20 wt%. . If it is less than 0.5 wt%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40 wt%, the low-temperature fixability deteriorates.
The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. If it is less than 1 per molecule, the molecular weight of the urea-modified polyester will be low, and the hot offset resistance will deteriorate.

Next, as amines (B) to be reacted with the polyester prepolymer (A), a divalent amine compound (B1), a trivalent or higher polyvalent amine compound (B2), an amino alcohol (B3), an amino mercaptan (B4) ), Amino acid (B5), and amino acid block of B1 to B5 (B6).
Examples of the divalent amine compound (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexyl). Methane, diamine cyclohexane, isophorone diamine, etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine, etc.) and the like. Examples of the trivalent or higher polyvalent amine compound (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of the compound (B6) obtained by blocking the amino group of B1 to B5 include ketimine compounds and oxazolidine compounds obtained from the amines of B1 to B5 and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

The ratio of amines (B) is equivalent to the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the polyester prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). Is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] is more than 2 or less than 1/2, the molecular weight of the urea-modified polyester is lowered, and the hot offset resistance is deteriorated.
The urea-modified polyester may contain a urethane bond together with a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

The urea-modified polyester is produced by a one-shot method or the like. Polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and water generated while reducing the pressure as necessary. Distill off to obtain a polyester having a hydroxyl group. Subsequently, at 40-140 degreeC, this is made to react with polyvalent isocyanate (PIC), and the polyester prepolymer (A) which has an isocyanate group is obtained. Further, this (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a urea-modified polyester.
When reacting (PIC) and when reacting (A) and (B), a solvent may be used if necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And those inert to isocyanates (PIC), such as tetrahydrofuran (such as tetrahydrofuran).

In addition, in the crosslinking and / or extension reaction between the polyester prepolymer (A) and the amines (B), a reaction terminator can be used as necessary to adjust the molecular weight of the resulting urea-modified polyester. Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).
The weight average molecular weight of the urea-modified polyester is usually 10,000 or more, preferably 20,000 to 10,000,000, and more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of the urea-modified polyester or the like is not particularly limited when the above-mentioned unmodified polyester is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. When the urea-modified polyester is used alone, its number average molecular weight is usually 2000-15000, preferably 2000-10000, more preferably 2000-8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color apparatus are deteriorated.

By using the unmodified polyester and the urea-modified polyester in combination, the low-temperature fixability and the gloss when used in the full-color image forming apparatus 1 are improved. Therefore, it is preferable to use the urea-modified polyester alone. The unmodified polyester may include a polyester modified with a chemical bond other than a urea bond.
The unmodified polyester and the urea-modified polyester are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, it is preferable that the unmodified polyester and the urea-modified polyester have a similar composition.
The weight ratio of unmodified polyester to urea-modified polyester is usually 20/80 to 95/5, preferably 70/30 to 95/5, more preferably 75/25 to 95/5, and particularly preferably 80 /. 20-93 / 7. When the weight ratio of the urea-modified polyester is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.
The glass transition point (Tg) of the binder resin containing unmodified polyester and urea-modified polyester is usually 45 to 65 ° C, preferably 45 to 60 ° C. If it is less than 45 ° C., the heat resistance of the toner deteriorates, and if it exceeds 65 ° C., the low-temperature fixability becomes insufficient.
In addition, since the urea-modified polyester is likely to be present on the surface of the obtained toner base particles, the heat-resistant storage stability tends to be good even when the glass transition point is low as compared with known polyester-based toners.

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

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

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

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

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

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

2) The toner material liquid is emulsified in an aqueous medium in the presence of a surfactant and resin fine particles.
The aqueous medium may be water alone or an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). It may be included.
The amount of the aqueous medium used relative to 100 parts by weight of the toner material liquid is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight. If the amount is less than 50 parts by weight, the dispersion state of the toner material liquid is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 20000 parts by weight, it is not economical.

Further, in order to improve the dispersion in the aqueous medium, a dispersant such as a surfactant and resin fine particles is appropriately added.
As surfactants, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, fatty acid amide derivative, polyhydric alcohol Nonionic surfactants such as derivatives, for example, amphoteric surfactants such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine And the like.

Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-Hydroxyethyl) Perful Olooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Can be mentioned.
Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Daikin Industries, Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (manufactured by Dainippon Ink, Inc.), Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).

  Further, as the cationic surfactant, aliphatic quaternary ammonium salts such as aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, and perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts. , Benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (manufactured by Asahi Glass), Florard FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (Daikin Industries) Manufactured), MegaFuck F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products), Footgent F-300 (Neos), and the like.

The resin fine particles are added to stabilize the toner base particles formed in the aqueous medium. For this reason, it is preferable to add so that the coverage existing on the surface of the toner base particles is in the range of 10 to 90%. For example, polymethyl methacrylate fine particles 1 μm and 3 μm, polystyrene fine particles 0.5 μm and 2 μm, poly (styrene-acrylonitrile) fine particles 1 μm, trade names are PB-200H (manufactured by Kao), SGP (manufactured by Soken), Techno Examples include polymer SB (manufactured by Sekisui Chemical Co., Ltd.), SGP-3G (manufactured by Sokensha), and micropearl (manufactured by Sekisui Fine Chemical Co., Ltd.).
In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.

  As a dispersant that can be used in combination with the above resin fine particles and inorganic compound dispersant, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Bodies such as acrylic acid-β-hydroxyethyl, methacrylic acid-β-hydroxyethyl, acrylic acid-β-hydroxypropyl, methacrylic acid-β-hydroxypropyl, acrylic acid-γ-hydroxypropyl, methacrylic acid-γ-hydroxy Propyl, acrylic acid-3-chloro-2-hydroxypropyl, methacrylic acid-3-chloro-2-hydroxypropyl, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate Luric acid esters, N-methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or compounds containing vinyl alcohol and a carboxyl group Esters such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl Nitrogen compounds such as imidazole and ethyleneimine, or homopolymers or copolymers such as those having a heterocyclic ring thereof, polyoxyethylene, poly Xoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxy Polyoxyethylenes such as ethylene nonylphenyl ester, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

  The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. Among these, the high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.

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

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

5) A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are externally added to obtain a toner.
When the external additive and the lubricant 201 are added to prepare the developer, these may be added simultaneously or separately and mixed. For mixing external additives and the like, a general powder mixer is used, but it is preferable to equip a jacket or the like to adjust the internal temperature. Examples of the mixing equipment that can be used include a V-type mixer, a rocking mixer, a Ladige mixer, a Nauter mixer, a Henschel mixer, and the like. It is preferable to prevent the embedding of the external additive and the formation of a thin film on the toner surface of the lubricant 201 by changing the mixing conditions such as the rotational speed, rolling speed, time, and temperature.
Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the spherical shape and the spindle shape can be controlled, and the surface morphology is also controlled between the smooth shape and the umeboshi shape. Can do.

  The toner of the present invention can be mixed with a magnetic carrier and used as a two-component developer. In this case, the toner concentration of the carrier and the toner in the developer is preferably 1 to 10 parts by weight of the toner with respect to 100 parts by weight of the carrier. The toner of the present invention can also be used as a one-component magnetic toner that does not use a carrier or a non-magnetic toner.

  Further, at least the photosensitive belt 2 for forming a latent image and the lubricant applying unit 20 are integrally supported, and the process cartridge is detachable from the main body of the image forming apparatus 1. As a result, when maintenance becomes necessary, the process cartridge can be replaced, and convenience is improved.

1 illustrates a configuration of a main part of an image forming apparatus according to an embodiment of the present invention. It is the schematic which shows the structure of a lubricant application means. It is a figure explaining an Euler belt system. 2 is a timing chart of a motor that is a drive source of a lubricant application brush and a clutch that transmits rotation from the drive source to the lubricant application brush. FIG. 6 is a diagram schematically illustrating the shape of a toner, where (a) illustrates a shape factor SF-1, and (b) illustrates a shape factor SF-2. 2A and 2B are schematic diagrams illustrating an outer shape of a toner, where FIG. 1A is an appearance of the toner, and FIG. 2B is a cross-sectional view of the toner.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Photoconductor belt 6 Charging apparatus 8 Developing apparatus 10 Transfer apparatus 101 Intermediate transfer belt 102 Secondary transfer roller 103 Cleaning brush 14 Cleaning apparatus 20 Lubricant application means 201 Lubricant 202 Application brush

Claims (13)

Lubricant application means comprising a rotating image carrier and a rotatable brush arranged in contact with the image carrier and applying a lubricant to the image carrier, and the brush is always in contact with the lubricant In
The rotatable brush is controlled by switching ON / OFF timing of rotation. In the lubricant application means according to claim 1,
In the rotatable brush, the ON / OFF timing of the rotation is controlled with a duty ratio in which a time T2 that is not at least an integer ratio of the time T1 required for one rotation of the image carrier is 100%. Lubricant application means. In the lubricant application means of claims 1 and 2,
The image forming apparatus, wherein the rotation operation of the rotatable brush is turned off at least when the image carrier is not rotating. At least a lubricant that is arranged in contact with the rotating image carrier and the rotatable brush for applying a lubricant to the image carrier, and the brush is always in contact with the lubricant. In a process cartridge comprising application means,
The rotatable brush is controlled by switching ON / OFF timing of rotation. The process cartridge according to claim 4, wherein
The process cartridge comprises the lubricant application unit according to claim 2 or 3. Lubricant application means comprising a rotating image carrier and a rotatable brush arranged in contact with the image carrier and applying a lubricant to the image carrier, and the brush is always in contact with the lubricant In an image forming apparatus having
An image forming apparatus comprising: control means for arbitrarily switching ON / OFF timing of rotation of the rotatable brush, wherein one circumference of the image carrier is equal to or greater than a maximum image length of the image forming apparatus. The image forming apparatus according to claim 6.
Means for variably controlling the ON / OFF timing of the rotation of the rotatable brush with a duty ratio in which a time T2 not at least an integer ratio of the time T1 required for one rotation of the image carrier is 100%. An image forming apparatus. 8. The image forming apparatus according to claim 6, wherein the rotation operation of the rotatable brush is turned off at least when the image carrier is not rotating. The image forming apparatus according to any one of claims 6 to 8,
The toner used in the developing unit has a volume average particle diameter of 3 to 8 μm and a ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) of 1.00 to 1.40. An image forming apparatus characterized by being in the range. The image forming apparatus according to any one of claims 6 to 9,
The image forming apparatus, wherein the toner used in the developing unit has a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180. The image forming apparatus according to claim 6,
The toner used in the developing means crosslinks a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent is dispersed in an organic solvent in an aqueous medium. And / or an image forming apparatus, wherein the toner is obtained by an extension reaction. 12. The image forming apparatus according to claim 6, wherein:
An image forming apparatus, wherein the toner used in the developing unit has a substantially spherical shape. The image forming apparatus according to any one of claims 6 to 12,
The image forming apparatus includes the process cartridge according to claim 4.

Images