JP4866046B2 - Lubricant coating apparatus, process cartridge, and image forming apparatus - Google Patents

Description

  The present invention relates to a coating apparatus that applies a lubricant to an image carrier, and as an application, a process cartridge, a transfer apparatus, and an image forming apparatus in an electrophotographic apparatus.

An image forming apparatus using an electrophotographic process includes a photoconductor as an image carrier, and charges the surface of the photoconductor by discharging to form an electrostatic latent image by exposing the charged photoconductor surface. A toner is supplied to the electrostatic latent image to make it visible, and the visible image formed on the surface of the photoreceptor is transferred onto the surface of the transfer paper, and then fixed and discharged. Since the untransferred toner remains on the surface of the photoconductor after the transfer of the visible image, the photoconductor surface is cleaned by a cleaning device so that they do not adversely affect the next image formation. Be prepared for the process. As a cleaning device, a cleaning blade made of an elastic material such as rubber or a cleaning brush in which synthetic resin fibers are formed in a brush shape is rubbed against the surface of the photosensitive member to remove deposits such as untransferred toner. Known.
However, the cleaning blade and the cleaning brush as described above have a problem that if they are continuously rubbed with the photosensitive member, they are worn with time and the cleaning performance is deteriorated due to chipping or deformation. Further, since the surface of the photoconductor is also worn, the life is shortened. Therefore, in order to reduce the frictional resistance acting between the photoconductor and these cleaning members and to eliminate problems such as wear of the cleaning member and photoconductor, there is a method of applying a lubricant to the surface of the photoconductor. It has been taken. Also, if a lubricant is applied to the surface of the photoconductor, the coefficient of friction on the surface of the photoconductor decreases, so that a fluidizing agent or a charge control agent added to the toner is applied to the surface of the photoconductor by the contact pressure with the cleaning member. It is possible to prevent so-called filming that is fixed in a film form. Transferability of the toner developed on the photoreceptor is also improved by reducing the adhesive force with the surface of the photoreceptor.

By the way, in recent years, a demand for higher image quality has been increasing, and in order to realize particularly high-definition color image formation, toner particle diameters and spheroidization have been promoted. The reproducibility of dots is improved by reducing the particle size, and the developability and transferability can be improved by making the particles spherical. Since it is very difficult to produce such a small particle size and spherical toner by the conventional kneading and pulverization method, the polymerization produced by suspension polymerization method, emulsion polymerization method, dispersion polymerization method, etc. Toner is being adopted.
However, when a toner having a spherical shape and a reduced particle size is used, there are some problems in cleaning on the photoreceptor after image formation. One of them is that it is difficult to clean a toner having a spherical shape and a small particle size by using a blade cleaning method generally used. The cleaning blade removes toner while rubbing the surface of the photoconductor, but the edge portion of the cleaning blade is deformed due to frictional resistance with the photoconductor, so that a minute space is generated between the photoconductor and the cleaning blade. The smaller the toner particle size, the easier it is to enter this space. Since the rolling friction force is smaller as the invading toner has a shape close to a spherical shape, it starts to roll in the space between the photosensitive member and the cleaning blade, passes through the cleaning blade, and leads to poor cleaning.

As a measure for preventing such a cleaning failure, for example, a method of increasing the contact pressure of the cleaning blade to the photosensitive member is taken. As a result, the frictional force with the surface of the photoreceptor increases, and the cleaning blade is more easily damaged and worn. Further, blade squealing or blade turning caused by irregular vibration of the cleaning blade is likely to occur. Therefore, a technique for uniformly applying a lubricant to the surface of the photoconductor has been proposed (see, for example, Patent Right 1). Thus, it is more important to reduce the coefficient of friction on the surface of the photoconductor. ing.
As means for applying a lubricant to the surface of the photoreceptor, for example, there are the following apparatuses.
A solid lubricant obtained by molding a lubricant such as a fatty acid metal salt into a rod shape is installed, and a brush roller is provided so as to contact both the solid lubricant and the photosensitive member. The lubricant application means is installed in front of the cleaning means, and when the brush roller is driven to rotate, the solid lubricant is scraped by the friction between the brush roller and the toner and becomes powder and adheres to the brush fibers of the brush roller. A powdery lubricant adhering to the brush roller is applied to the surface of the photoreceptor.
However, in an apparatus provided with a lubricant application means before the cleaning means, the way the lubricant is scraped differs depending on the presence or absence of a toner image, and the formation of a protective film on the photoreceptor also causes a deviation and is difficult to control. It is.

JP 2002-244485 A

However, in the lubricant application means before the cleaning, the solid lubricant is scraped by the brush roller bristles and the toner attached to the brush roller, whereas in the apparatus for applying the lubricant after the cleaning means, Since the only means for scraping the solid lubricant is the bristles of the brush roller, the uniformity on the surface to be coated is easily affected by the flocking density and fiber thickness of the brush. If the lubricant is not applied to the surface to be coated, there will be partial wear or conversely contamination.
The uneven coating tends to occur when the fiber thickness is large and the flocking density is sparse. Further, if the fiber thickness is thin and the flocking density is sparse, there is no cutting force and application is impossible. These are particularly susceptible to fiber thickness.

In the first aspect of the present invention, a brush roller that has a surface to be coated and a cleaning device that cleans the surface to be coated , scrapes and applies a solid lubricant to the surface to be coated, and a tray on the surface to be coated. A lubricant application device having a sheet-like homogenizing member for extending the solid lubricant on the surface to be applied to the surface to be applied by contacting in a ring posture, the lubricant application device comprising: Regarding the moving direction of the application surface, the solid lubricant is disposed downstream of the cleaning device, the unit of fiber thickness of the brush roller is [d: denier], and the unit of flocking density is [thousand / inch ² ]. Application unevenness Application unevenness = (Fiber thickness) ³ ÷ (Flocking density)
When defining with
Uneven coating ≦ 6.9
And the cutting force with which the brush roller cuts the solid lubricant is determined using the fiber thickness and flocking density of the brush roller.
Cutting force = (fiber thickness) ² x (flocking density)
When defining with
Cutting force ≧ 200
It is characterized by satisfying.

According to a second aspect of the present invention, in the lubricant application device according to the first aspect, the material of the brush portion of the brush roller is polyester.

According to a third aspect of the present invention, in the lubricant application device according to the first or second aspect , the brush roller is grounded.
According to a fourth aspect of the present invention, in the lubricant application device according to any one of the first to third aspects, the brush roller has conductivity.
According to a fifth aspect of the present invention, in the lubricant application device according to any one of the first to fourth aspects, the surface to be coated is a photoconductor.
According to a sixth aspect of the invention, there is provided a process cartridge in which the lubricant applying device according to the fifth aspect and at least the photosensitive member are integrally provided so as to be attachable to the image forming apparatus.

According to a seventh aspect of the invention, there is provided an image forming apparatus having the lubricant application device according to any one of the first to fifth aspects.
According to an eighth aspect of the present invention, in the image forming apparatus according to the seventh aspect , the volume average particle size is 10 μm or less, and the ratio (dispersion degree) between the volume average particle size and the number average particle size is 1.00. Or a toner in the range of 1.40.
According to a ninth aspect of the present invention, in the image forming apparatus according to the seventh or eighth aspect , a toner having an average circularity in a range of 0.93 to 1.00 is used.
According to a tenth aspect of the present invention, in the image forming apparatus according to any one of the seventh to ninth aspects, the shape factor SF-1 is 100 to 180 and the shape factor SF-2 is 100 to 180. A toner in the range is used.

According to an eleventh aspect of the present invention, in the image forming apparatus according to any one of the seventh to tenth aspects, the external shape is a substantially spherical shape, and a relationship of major axis r1 ≧ minor axis r2 ≧ thickness r3. The ratio of the minor axis to the major axis (r2 / r1) is in the range of 0.5 to 1.0, and the ratio of the thickness to the minor axis (r3 / r2) is 0.7 to 1.0. A toner having a range is used.
According to a twelfth aspect of the present invention, in the image forming apparatus according to any one of the eighth to eleventh aspects, the toner includes at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, It is a toner obtained by crosslinking and / or extending a toner composition containing a release agent in the presence of resin fine particles in an aqueous medium.
According to a thirteenth aspect of the present invention, the image forming apparatus according to any one of the seventh to twelfth aspects is characterized by a tandem type image forming apparatus having a plurality of photoconductors.

According to the present invention, the relationship between the fiber thickness of the brush roller and the flocking density is specified , and the lubricant applied on the surface to be applied is stretched by the uniformizing member, so that uneven application of the lubricant can be prevented, and The lubricant can be cut reliably, and the coated surface can be reliably protected.
Since the material of the brush roller is polyester, there is little deformation even when used for a long period of time, so that the lubricant can be cut stably, and the coated surface can be reliably protected.
Since the brush roller is made conductive and grounded, charging of the brush roller can be reduced or prevented, so that damage to the coated surface due to discharge can be reduced.
Since the lubricant coating apparatus of the present invention is applied to the photoreceptor, the surface of the photoreceptor can be uniformly protected, so that a long-life photoreceptor can be provided.
Since the process cartridge is configured by integrating the lubricant application device of the present invention and the photosensitive member, a process cartridge having a long life can be provided.
Since the image forming apparatus includes the lubricant application device of the present invention, it is possible to provide a long-life image forming apparatus.
In the image forming apparatus provided with the lubricant application device of the present invention, the relationship between the volume average particle size and the number average particle size of the toner, the average circularity, the shape factor, and the relationship between the major axis, minor axis, and thickness, Since the toner material and the manufacturing method thereof are specified, a high-quality image forming apparatus can be provided.

FIG. 1 is a diagram showing the overall configuration of an image forming apparatus to which the present invention is applied.
In the figure, reference numeral 1 is a photoconductor, 2 is a charging device, 3 is a developing device, 4 is an intermediate transfer device, 5 is a transfer device, 6 is a cleaning device, 7 is a lubricant application device, 8 is a fixing device, and 9 is a discharge device. Paper roller, 10 is an exposure device, 11 is a registration roller, 21 is a paper feeding roller, 31 is a reading traveling body, 32 is a contact glass, 33 is a lens, 34 is a CCD, 100 is an image forming unit, 200 is a paper feeding unit, Reference numeral 300 denotes a paper discharge storage unit, 500 denotes a process cartridge, and L denotes an exposure light beam.
An image forming unit 100 is disposed substantially at the center of the in-body discharge type image forming apparatus, and a sheet feeding unit 200 is disposed immediately below the image forming unit 100. If necessary, another sheet feeding device can be added at the bottom. Above the image forming unit 100, a reading unit 300 that reads a document through the paper discharge storage unit 400 is disposed. A recording medium (hereinafter referred to as paper) on which an image is formed is discharged and stored in the discharge storage unit 400. The dotted arrows in the figure indicate the paper path.
In the image forming unit 100, a charging device 2 that charges the surface of the photosensitive member 1 around the drum-shaped photosensitive member 1, an exposure device 10 that irradiates the photosensitive member surface with laser light with image information, and a photosensitive member ( A developing device 3 for visualizing an electrostatic latent image formed by being exposed on the surface of 1, an intermediate transfer device 4 for superimposing toner images respectively developed on a plurality of photoreceptors 1, a transfer device 5 for transferring to a sheet, A cleaning device 6 that removes and collects toner remaining on the surface of the photoconductor after transfer, a lubricant application device 7 that lowers the coefficient of friction on the surface of the image carrier such as the photoconductor 1, and fixing the toner on the paper from which the toner image was obtained. A fixing device 8 to be processed is disposed downstream in the paper conveyance path, and the photosensitive member 1, the charging device 2, the developing device 3, the cleaning device 6 and the like are designated as a process cartridge 500 in order to facilitate maintenance. And detachable from the embedded main unit to the unit. The same housed reasons the cleaning device 6 'and the lubricant applying device 7' and in one unit and detachably attached to the intermediate transfer device 4 Further, the cleaning device 6 ″ , the lubricant application device 7 ″, and the transfer device 5 are integrally accommodated so as to be detachable from the main body device. Then, the paper is stored in the paper storage unit 400.

In the paper feed unit 200, unused paper S is accommodated, and the uppermost paper is sent out from the paper feed cassette by the rotation of the paper feed roller 21 and conveyed to the registration roller 11. The registration roller 11 is controlled to start rotation at a timing so that the conveyance of the sheet S is temporarily stopped and the positional relationship between the toner image on the surface of the photosensitive member and the leading end of the sheet becomes a predetermined position.
In the reading unit 300, in order to read and scan a document (not shown) placed on the contact glass 32, a reading traveling body 31 including a document illumination light source and a mirror reciprocates. Image information scanned by the reading traveling body 31 is read as an image signal into the CCD 34 installed behind the lens 33. The read image signal is digitized and subjected to image processing. Based on the image-processed signal, the surface of the photosensitive member 1 is irradiated with the exposure light beam L by the light emission of a laser diode (not shown) of the exposure apparatus 10 to form an electrostatic latent image. The optical signal from the laser diode reaches the photosensitive member via a known polygon mirror or lens.

FIG. 2 is a view for explaining the process cartridge of the present invention.
In the drawing, reference numeral 510 denotes a photosensitive drum, 521 a charging member, 522 an urging member, 530 a developing device, 531 a developing roller, 532 a developing doctor, 533 a sales expansion screw, 541 an intermediate transfer belt, and 542 a transfer. Bias roller, 560 indicates a cleaning device, 571 indicates a lubricant application member, 572 indicates a solid lubricant, 573 indicates a biasing member, and 574 indicates a leveling member.
The charging device 520 mainly includes a charging member 521 and an urging member 522 that pressurizes the charging member 521 to the photoreceptor 510 with a predetermined pressure. The charging member 521 has a conductive elastic layer around a conductive shaft. A predetermined voltage is applied to the gap between the conductive elastic layer and the photoconductor 510 through a conductive shaft by a voltage application device (not shown) to apply a charge to the surface of the photoconductor. In the developing device 530, the developer is sufficiently stirred by the stirring screw 533 and is magnetically attached to the developing roller 531. The attached developer is thinned on the developing roller 531 by the developing doctor 532. The electrostatic latent image on the photosensitive member 510 is visualized by the thinned developer. The visualized toner image is electrically attached onto the intermediate transfer belt 541 by the transfer bias roller 542. Residual toner that has not been transferred onto the intermediate transfer belt 541 is removed from the photoreceptor 510 by the cleaning device 560. The lubricant application member 571 is formed in a roller shape by winding a brush around a metal shaft. The solid lubricant 572 is urged to the lubricant application member 571 by the urging member 573. By rotating the lubricant application member 571, the solid lubricant 572 is scraped into fine powder, and the lubricant is applied to the surface of the photoreceptor 510. Apply. The lubricant application member 571 rotates in the same direction as the photoconductor 510. The powder lubricant applied to the photoconductor 510 is pressed and extended on the surface of the photoconductor 510 by the leveling member 574.

In the image forming apparatus of the present invention, the toner used in the developing device 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). It is preferably in the range of 1.00 to 1.40.
By using a toner having a small particle diameter, the toner can be densely attached to the latent image. However, when the volume average particle size is smaller than the range of the present invention, in the case of a two-component developer, the toner is fused to the surface of the magnetic carrier during a long period of stirring in the developing device, and the charging ability of the magnetic carrier is reduced. When used as a developer, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur. Conversely, when the volume average particle diameter of the toner is larger than the above range, it becomes difficult to obtain a high-resolution and high-quality image, and the toner in the developer is balanced. In many cases, the variation in the particle size of the particles increases.
Further, by narrowing the particle size distribution, the toner charge amount distribution becomes uniform, a high-quality image with little background fogging can be obtained, and the transfer rate can be increased. However, it is not preferable that Dv / Dn exceeds 1.40 because the charge amount distribution becomes wide and the resolving power decreases.
The average particle size and particle size distribution of the toner can be measured using a Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). In the present invention, measurement was performed by using a Coulter counter TA-II type connected to an interface (manufactured by Nikka Giken Co., Ltd.) for outputting number distribution and volume distribution, and a personal computer (PC9801: manufactured by NEC Corporation).

In the present invention, an image forming apparatus that can achieve the effect of mounting the cleaning blade 560 is a case where the toner used in the developing device 530 is a toner having a high degree of circularity with an average circularity of 0.93 or more. Toner with a high degree of circularity enters the gap between the image carrier and the cleaning blade in blade-type cleaning, and easily slips through. When the contact pressure of the cleaning blade 560 to the image carrier is increased, the damage to the image carrier increases. Also, in the method of electrostatically collecting toner by applying a bias reverse to the charging polarity of the toner to the brush roller, it is difficult to remove the toner from the brush roller. There is a tendency that the toner removing ability is lowered.
However, the cleaning blade 560 can efficiently clean the surface of the image carrier as described below even when the above-described toner having a high average circularity is used.
The average circularity of the toner is a value obtained by dividing particles by the circumference of an equivalent circle having the same projected area after optically detecting particles. Specifically, the measurement is performed using a flow type particle image analyzer (FPIA-2000; manufactured by Sysmex Corporation). In a predetermined container, 100 to 150 mL of water from which impure solids are removed in advance is added, 0.1 to 0.5 mL of a surfactant is added as a dispersant, and about 0.1 to 9.5 g of a measurement sample is further added. The suspension in which the sample is dispersed is subjected to dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the dispersion concentration is set to 3,000 to 10,000 / μL, and the shape and distribution of the toner are measured.

FIG. 3 is a diagram schematically showing the shape of the toner in order to explain the shape factor. FIG. 4A is a diagram for explaining the shape factor SF-1, and FIG. 4B is a diagram for explaining the shape factor SF-2.
In the figure, symbol A indicates the projected area of the toner on an arbitrary plane, Lmax indicates the maximum outer diameter at that time, and Lper indicates the outer peripheral length at that time.
The shape factor SF-1 indicates the ratio of the roundness of the toner shape and is represented by the following formula (1). A value obtained by dividing the square of the maximum length Lmax of the shape formed by projecting the toner onto a two-dimensional plane by the figure area A and multiplying by 100π / 4.
SF-1 = {(Lmax) ² / A} × (100π / 4) Expression (1)
When the value of SF-1 is 100, the shape of the toner becomes a perfect circle, and becomes larger as the value of SF-1 increases. When SF-1 is 100 regardless of which plane is projected, the shape of the toner is a true sphere.
The shape factor SF-2 indicates the ratio of the unevenness of the toner shape, and is represented by the following formula (2). This is a value obtained by dividing the square of the perimeter Lper of the figure formed by projecting the toner on the two-dimensional plane by the figure area A and multiplying by 100 / 4π.
SF-2 = {(Lper) 2 / A} × (100 / 4π) (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.
The toner used in the image forming apparatus of the present invention preferably 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.

When the shape of the toner is close to a sphere, the contact between the toner and the toner, or the contact between the toner and the image carrier is close to a point contact. The attracting force with the photoreceptor 1 is also weakened, and the transfer rate is increased. On the other hand, since spherical toner tends to enter the gap between the cleaning blade 8a and the photoreceptor 1, the toner shape factor SF-1 or SF-2 is preferably large to some extent. Further, when SF-1 and SF-2 are increased, toner is scattered on the image and the image quality is lowered. For this reason, it is preferable that SF-1 and SF-2 do not exceed 180. Specifically, the shape factor is measured by taking a photograph of the toner with a scanning electron microscope (S-800: manufactured by Hitachi, Ltd.), and introducing it into an image analyzer (LUSEX 3: manufactured by Nireco) for analysis. And calculated.
The toner suitably used in the image forming apparatus of the present invention is, for example, a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent are dispersed in an organic solvent. Is a toner obtained by crosslinking and / or elongation reaction in an aqueous solvent. Here, the expression “crosslinking and / or extension reaction” means “performing at least one of crosslinking and extension reaction”. In the following, description will be given with examples of toner constituent materials and manufacturing methods.

(I) Modified Polyester The toner according to the present invention contains a modified polyester as a binder resin. The modified polyester refers to a state in which a bonding group other than an ester bond is present in the polyester resin, or resin components having different configurations are bonded to the polyester resin by a covalent bond, an ionic bond, or the like. Specifically, the polyester terminal is modified by introducing a functional group such as a carboxylic acid group or an isocyanate group that reacts with a hydroxyl group into the polyester terminal and further reacting with an active hydrogen-containing compound.
Examples of the modified polyester include urea-modified polyester obtained by a reaction between an isocyanate group-containing polyester prepolymer (A) and amines (B). As the polyester prepolymer (A) having an isocyanate group, a polyester having a polycondensate of a polyhydric alcohol (PO) and a polyvalent carboxylic acid (PC) and having an active hydrogen group is further added to a polyvalent isocyanate compound (PIC). And those reacted with. Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.

The urea-modified polyester is produced as follows.
Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable. Examples of the dihydric alcohol (DIO) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts.

  Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. The trihydric or higher polyhydric alcohol (TO) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

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

The ratio of the polyhydric alcohol (PO) to the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Is 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.
Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.) ); Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; Those blocked with caprolactam or the like; and combinations of two or more of these.

The ratio of the polyvalent isocyanate compound (PIC) is usually 5/1 to 1/1, preferably as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. When the molar ratio of [NCO] is less than 1, when a urea-modified polyester is used, the urea content in the ester is lowered and hot offset resistance is deteriorated.
The content of the polyvalent isocyanate compound (PIC) component in the polyester prepolymer (A) having an isocyanate group is usually 0.5 to 40 wt%, preferably 1 to 30 wt%, more preferably 2 to 20 wt%. . If it is less than 0.5 wt%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40 wt%, the low-temperature fixability deteriorates.
The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. If it is less than 1 per molecule, the molecular weight of the urea-modified polyester is lowered, and the hot offset resistance is deteriorated.

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 as well as a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.
The modified polyester used in the present invention is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the modified polyester is usually 10,000 or more, preferably 20,000 to 10,000,000, more preferably 30,000 to 1,000,000. The peak molecular weight at this time is preferably 1000 to 10000. When the molecular weight is less than 1000, the elongation reaction hardly occurs, the elasticity of the toner is small, and as a result, the resistance to hot offset deteriorates. On the other hand, when it exceeds 10,000, the problem in production becomes high in the deterioration of fixability, particle formation and pulverization. The number average molecular weight of the modified polyester is not particularly limited when a non-modified polyester described later is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. In the case of the modified polyester alone, the number average molecular weight is usually 20000 or less, preferably 1000 to 10000, and more preferably 2000 to 8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color apparatus are deteriorated.

In the crosslinking and / or extension reaction between the polyester prepolymer (A) and the amines (B) to obtain a modified polyester, 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).
In addition, the molecular weight of the produced | generated polymer can be measured using THF as a solvent using gel permeation chromatography (GPC).

(Ii) Unmodified polyester In the present invention, not only the modified (i) polyester (hereinafter simply referred to as (i)) is used alone, but also (ii) and (ii) unmodified polyester (hereinafter simply referred to as “i”). (Denoted as (ii)) can be contained as a binder resin component. By using (ii) in combination, the low-temperature fixability and the gloss when used in a full-color device are improved, which is preferable to the single use. Examples of (ii) include polycondensates of a polyhydric alcohol (PO) and a polyvalent carboxylic acid (PC), which are the same as the polyester component (i), and preferred ones are also the same as (i). . Further, (ii) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, for example, may be modified with a urethane bond. It is preferable that (i) and (ii) are at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component (i) and (ii) preferably have similar compositions. In the case of containing (ii), the weight ratio of (i) to (ii) is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, Particularly preferred is 7/93 to 20/80. If the weight ratio of (i) is less than 5%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

The peak molecular weight of (ii) is 1000-10000 normally, Preferably it is 2000-8000, More preferably, it is 2000-5000. If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 10,000, low-temperature fixability will deteriorate. The hydroxyl value of (ii) is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. As for the acid value of (ii), 1-5 are preferable, More preferably, it is 2-4. Since a high acid value wax is used as the wax, the low acid value binder leads to electrification and high volume resistance, so that it is easy to match the toner used for the two-component developer.
The glass transition point (Tg) of the binder resin is usually 35 to 70 ° C, preferably 55 to 65 ° C. If it is less than 35 ° C., the heat resistant storage stability of the toner is deteriorated, and if it exceeds 70 ° C., the low-temperature fixability is insufficient. Since the urea-modified polyester is likely to be present on the surface of the obtained toner base particles, the toner of the present invention tends to have good heat storage stability even when the glass transition point is low, as compared with known polyester-based toners. Show.
The glass transition point (Tg) can be measured with a differential scanning calorimeter (DSC).

Colorant 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 , Fais red, parachloro Rutonitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carnmin BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing 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 , Thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolo 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, Indance Ren 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, Chrome Oxide, Pyridian, Emerald Green , Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Yellow, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, lithopone 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 together with the production of a master batch or a 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 resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax and the like can be mentioned, and these can be used alone or in combination.

Charge Control Agents 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 quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine-based 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 the release agent, a low melting point wax having a melting point of 50 to 120 ° C. works effectively between the fixing roller and the toner interface as a release agent in the dispersion with the binder resin. As a result, it is effective against high temperature offset without applying a release agent such as oil to the fixing roller. Examples of such a wax component include the following. Examples of waxes and waxes include plant waxes such as carnauba wax, cotton wax, wood wax, and rice wax, animal waxes such as beeswax and lanolin, mineral waxes such as ozokerite and cercin, and paraffin, microcrystalline, and petrolatum. And petroleum wax. 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 Additives Inorganic fine particles are preferably used as external additives 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 addition 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

Toner Manufacturing Method Next, a toner manufacturing method will be described. Here, although a preferable manufacturing method is shown, it is not limited to this.
First Step 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.

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

  As surfactants, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride, fatty acid amide derivatives, polyhydric alcohols 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, perfluoroalkyl carboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctane sulfonic acid diethanolamide, N-propyl-N- ( 2-hydroxyethyl) Perfluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is 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).
In addition, examples of the cationic surfactant include 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 Corporation), SGP (manufactured by Soken Co., Ltd.), Techno Examples include polymer SB (manufactured by Sekisui Chemical Co., Ltd.), SGP-3G (manufactured by Sokensha), and micropearl (manufactured by Sekisui Fine Chemical Co., Ltd.).
In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.

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

  The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. Among these, the high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the 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.

3rd process Simultaneously with preparation of an emulsion, amines (B) are added and it is made to react with the polyester prepolymer (A) which has 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.

Step 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.

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

FIG. 4 is a diagram schematically showing the shape of the toner according to the present invention.
In the figure, the symbol r indicates the diameter when the toner is projected onto a plane.
When the substantially spherical toner is regarded as an ellipsoid and defined by a major axis r1, a minor axis r2, and a thickness r3 (where r1 ≧ r2 ≧ r3), the toner of the present invention has a minor axis and a long axis. The ratio (r2 / r1) to the axis is preferably 0.5 to 1.0, and the ratio (r3 / r2) to the thickness and the minor axis is preferably in the range of 0.7 to 1.0.
When the ratio of the minor axis to the major axis (r2 / r1) is less than 0.5, the dot reproducibility and transfer efficiency are inferior because of the separation from the true spherical shape, and high-quality image quality cannot be obtained. On the other hand, if the ratio of thickness to minor axis (r3 / r2) is less than 0.7, the shape is close to a flat shape, and a high transfer rate like a spherical toner cannot be obtained. In particular, when the ratio of the thickness to the minor axis (r3 / r2) is 1.0, the rotating body has a major axis as a rotation axis, and the fluidity of the toner can be improved.
Note that r1, r2, and r3 were measured with a scanning electron microscope (SEM) while changing the angle of field of view and taking pictures.

The toner produced as described above can be used as a one-component magnetic toner that does not use a magnetic carrier, or a non-magnetic toner.
When used in a two-component developer, it may be used by mixing with a magnetic carrier, and the magnetic carrier is a ferrite containing a divalent metal such as iron, magnetite, Mn, Zn, Cu, A volume average particle size of 20 to 100 μm is preferred. If the average particle size is less than 20 μm, carrier adhesion is likely to occur on the photoreceptor during development, and if it exceeds 100 μm, the miscibility with the toner is low, the toner charge amount is insufficient, and charging failure during continuous use is likely to occur. . In addition, Cu ferrite containing Zn is preferable because of high saturation magnetization, but can be appropriately selected according to the process of the image forming apparatus. The resin for coating the magnetic carrier is not particularly limited, and examples thereof include silicone resin, styrene-acrylic resin, fluorine-containing resin, and olefin resin. The manufacturing method may be that the coating resin is dissolved in a solvent, sprayed into a fluidized bed, and coated on the core, or the resin particles are electrostatically attached to the core particles and then thermally melted for coating. You may do. The resin to be coated has a thickness of 0.05 to 10 μm, preferably 0.3 to 4 μm.

The sheet-like leveling member is a urethane rubber sheet having a thickness of 1.6 mm manufactured by Toyo Tire & Rubber Co., Ltd. The contact pressure is 55 ± 10 (g / cm) when the photosensitive member is set, and the contact angle is about 10 °. Installed in a trailing posture so that the application brush is a conductive polyester brush with a foot length of 3 mm manufactured by Ashiya Co., Ltd. Create The brush flocking density and fiber thickness were tested as shown in the table below. Note that the conductive brush is more effective when grounded.
These process cartridges were put into Imagio NeoC325 manufactured by Ricoh Co., Ltd., and 1000 sheets were continuously passed under the laboratory environment under the condition of A4 size paper sideways.
As a result, it was found that coating unevenness is caused by the balance between the fiber thickness and the flocking density, and the thicker fiber thickness tends to occur and the lower flocking density tends to occur. It was also found that the coating unevenness contributed particularly greatly to the fiber thickness.
These relationships are expressed as empirical formulas as follows. However, the unit of fiber thickness is [d: denier], and the unit of flocking density is [1000 / inch ² ].
Application unevenness = (fiber thickness) ³ ÷ (Flocking density)
To give a weight to the fiber thickness with a particularly large contribution rate, it was raised to the third power.
The calculation results of the above equation are shown in Table 1. The underlined numerical value is a combination in which streaky stains due to coating unevenness and abnormal images due to poor cleaning occur at the end of paper passing. In the combination where the calculated value was 34.3 or less, coating unevenness did not occur.

Experiments on the cutting force of the solid lubricant were also performed under the same conditions as in Example 1.
As a result, it was found that the cutting force was also caused by the balance between the fiber thickness and the flocking density, the thinner the fiber thickness, the less cutting force, and the lower the flocking density, the smaller the cutting force. Although the linear velocity of the brush fiber to the solid lubricant by the rotation of the brush roller was changed in the range of 80 to 200 mm / sec, it was found that there was almost no contribution from the linear velocity. It was also found that the cutting force contributed more greatly to the fiber thickness.
These relationships are expressed as empirical formulas as follows. However, the unit of fiber thickness is [d: denier], and the unit of flocking density is [1000 / inch ² ].
Cutting force = (fiber thickness) ² x (flocking density)
Squared to weight the fiber thickness with a large contribution rate.
The calculation results of the above equation are shown in Table 2. The underlined numerical value is a combination in which filming occurs due to insufficient cutting force at the end of paper passing, that is, insufficient coating amount.
Filming did not occur in combinations where the calculated value was 200 or more.

1 is a diagram illustrating an overall configuration of an image forming apparatus to which the present invention is applied. It is a figure for demonstrating the process cartridge of this invention. FIG. 3 is a diagram schematically illustrating the shape of a toner for explaining a shape factor. FIG. 3 is a diagram schematically illustrating the shape of a toner according to the present invention.

Explanation of symbols

100 Image forming unit

200 Paper Feed Unit 300 Reading Unit 400 Paper Discharge Storage Unit 500 Process Cartridge 510 Photoconductor 560 Cleaning Blade 571 Brush Roller 572 Solid Lubricant 574 Leveling Member

Claims (13)

The surface to be coated has a surface to be coated and a cleaning device for cleaning the surface to be coated, and a brush roller for scraping and applying a solid lubricant on the surface to be coated, and a trailing posture against the surface to be coated. A lubricant application device having a sheet-like homogenizing member for extending the solid lubricant on the application surface to the application surface, wherein the lubricant application device moves in the moving direction of the application surface. With respect to the unevenness of the solid lubricant, the unit is disposed downstream of the cleaning device, the unit of the fiber thickness of the brush roller is [d: denier], and the unit of flocking density is [1000 / inch ² ]. = (Fiber thickness) ³ ÷ (Flocking density)
When defining with
Uneven coating ≦ 6.9
And the cutting force with which the brush roller cuts the solid lubricant is determined using the fiber thickness and flocking density of the brush roller.
Cutting force = (fiber thickness) ² x (flocking density)
When defining with
Cutting force ≧ 200
A lubricant application device characterized by satisfying 2. The lubricant application device according to claim 1 , wherein a material of a brush portion of the brush roller is polyester. 3. The lubricant application device according to claim 1, wherein the brush roller is grounded. In the lubricant coating apparatus according to any one of claims 1 to 3, the brush roller lubricant applying device, characterized in that electrically conductive. In the lubricant coating apparatus according to any one of claims 1 to 4, lubricant applicator, wherein the coated surface is a photosensitive member. 6. A process cartridge comprising: the lubricant application device according to claim 5 ; and at least a photoconductor, integrally configured so as to be attachable to an image forming apparatus. An image forming apparatus characterized by having a lubricant coating apparatus according to any one of claims 1 to 5. 8. The toner according to claim 7 , wherein the volume average particle diameter is 10 μm or less and the ratio (dispersity) of the volume average particle diameter to the number average particle diameter is in the range of 1.00 to 1.40. An image forming apparatus using the image forming apparatus. 9. The image forming apparatus according to claim 7 , wherein a toner having an average circularity in a range of 0.93 to 1.00 is used. 10. The image forming apparatus according to claim 7 , wherein a toner having a shape factor SF-1 of 100 to 180 and a shape factor SF-2 of 100 to 180 is used. An image forming apparatus. 11. The image forming apparatus according to claim 7 , wherein the short axis and the long axis when the external shape is substantially spherical and the long axis r1 ≧ the short axis r2 ≧ the thickness r3. And a ratio (r2 / r1) of 0.5 to 1.0 and a ratio of thickness to minor axis (r3 / r2) of 0.7 to 1.0. An image forming apparatus. 12. The image forming apparatus according to claim 8 , wherein the toner includes a toner composition including at least a polyester prepolymer having a functional group including a nitrogen atom, a polyester, a colorant, and a release agent. An image forming apparatus, wherein the toner is a cross-linked and / or extended toner in an aqueous medium in the presence of resin fine particles. 13. The tandem image forming apparatus according to claim 7 , further comprising a plurality of photoconductors.

Images