JP2010266512A - Developing roller and developing device using the same, process cartridge, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing roller having optimal electric characteristics in a single-component developing system, and to provide a developing device which uses the roller, a process cartridge and image forming apparatus. <P>SOLUTION: In the developing roller has at least a double-layer structure, including a base layer constituted of an elastic body provided on a surface of an electroconductive core bar; and a surface layer provided on the base layer, a complex impedance plot obtained, when an alternating voltage is applied while changing frequencies has two peaks: a first peak width of 10<SP>7</SP>-10<SP>8</SP>Ω, and a first peak height of 10<SP>6</SP>-10<SP>8</SP>Ω; and a second peak width of 10<SP>4</SP>-10<SP>7</SP>Ω, and a second peak height of 10<SP>3</SP>-10<SP>7</SP>Ω. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a developing roller for one-component contact development, a developing device using the same, a process cartridge, and an image forming apparatus.

  Dry development methods employed in electrophotography, electrostatic recording, and the like include a method using a two-component developer composed of a toner and a carrier and a method using a one-component developer not containing a carrier. The former two-component development method can provide a relatively stable and good image, but it is likely to cause deterioration of the carrier and a change in the mixing ratio of the toner and the carrier. Is difficult to obtain, and there are difficulties in maintaining and managing the apparatus and making it compact. In view of this, a method using the latter one-component developer which does not have such drawbacks has been attracting attention. In this one-component development system, toner is held on a developing roller as a toner conveying member, and the held toner is pressed by a regulating member, thereby adjusting the charging and layer thickness of the toner.

As a developing roller used in the one-component developing system, Patent Document 1 proposes a developing roller using a conductive elastic rubber member that draws a single curve in a complex impedance plot when an alternating voltage of a predetermined frequency is applied. ing. In Patent Document 2, a conductive base layer and an insulating surface layer made of a rubber base material having an electric resistance value of 10 ⁷ Ω or less are formed, and the total electric resistance value including the base layer and the surface layer is 10 ⁷ Ω or less. A developing roller using a semiconductive rubber member is proposed. Patent Document 3, the developing roller and the resistance value of ¹⁰ 10 Ω · cm or less semi-conductive elastic layer, and a conductive surface layer resistance consists ¹⁰ 10 Ω · cm or less in the polyurethane resin is formed proposed Has been.

  In the one-component development method, charging rises to a desired charge level at the moment when the toner on the developing roller passes through the regulating portion between the regulating member, and the toner on the developing roller is reliably on the developing roller by the mirror image force. Need to be retained. In other words, the developing roller needs to have electric characteristics such that the electric charge can be moved more smoothly, and on the other hand, it has a certain degree of insulation and retains the electric charge. When the toner charge level and the charge start-up property are reduced and the toner charge amount becomes insufficient, the toner adheres to the non-image part of the latent image carrier (photoconductor) to which the toner is supplied, and an undesired image part is formed. A so-called background stain is formed. Further, when the mirror image force is reduced, toner scattering from the developing roller occurs. However, the actual situation is that the conventional developing roller cannot sufficiently cope with such a problem specific to the one-component developing system.

The developing roller disclosed in Patent Document 1 shows a single peak in a complex impedance plot, and is a case of a single layer or a plurality of layers having the same electrical characteristics. Such a developing roller cannot sufficiently cope with the unique problem of the one-component developing system that requires both the charge level and the toner retention by the mirror image force. Since the developing roller disclosed in Patent Document 2 has a low resistance of the entire developing roller and a low resistance of the base layer, the insulating surface layer is expected to be a thin film. However, the resistance of the surface layer is described as 10 ¹⁰ to 10 ¹⁵ Ω · cm. If the resistance of the surface layer is too high, the charging level is high, but the charge rising property is lowered, and the above-described one-component development system is used. Cannot cope with specific issues. In the developing roller disclosed in Patent Document 3, the exchange of charges between the semiconductive elastic body layer and the conductive surface layer is expected to be accelerated. However, since the conductive surface layer has a lower resistance than the semiconductive elastic layer, the charge level and the image power are reduced, and the above-mentioned specific problems of the one-component development method are sufficiently addressed. Can not.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a developing roller having optimum electrical characteristics in a one-component developing system, and a developing device, a process cartridge, and an image forming apparatus using the developing roller. That is.

In order to solve the above problems, the invention of claim 1 is a development roller having at least a two-layer structure of a base layer made of an elastic body provided on the surface of a conductive core metal and a surface layer provided on the base layer. The complex impedance plot when an alternating voltage is applied at different frequencies has two peaks, the first peak width is 10 ⁷ Ω or more and 10 ⁸ Ω or less, and the first peak height is 10 ⁶ Ω or more 10 ⁸ Ω or less, the second peak width is 10 ⁴ Ω or more and 10 ⁷ Ω or less, and the second peak height is 10 ³ Ω or more and 10 ⁷ Ω or less.
According to a second aspect of the present invention, in the developing roller of the first or second aspect, when the first peak width is Zs and the second peak width is Zb, Zs> Zb and 5000> Zs / Zb> 50. It is characterized by satisfying.
According to a third aspect of the present invention, in the developing roller of the first aspect, the material constituting the base layer includes at least one of urethane rubber, chloropyrene rubber, butadiene acrylonitrile, epichlorohydrin rubber, and a JIS-A hardness of 40. It is characterized by being not less than 50 ° and not more than 50 °.
According to a fourth aspect of the present invention, there is provided a developing roller having a developing roller disposed opposite to the electrostatic latent image holding member that holds the electrostatic latent image, and a regulating member that regulates a layer thickness of the toner supplied onto the developing roller. In the apparatus, the developing roller according to claim 1, 2 or 3 is used as the developing roller.
According to a fifth aspect of the present invention, there is provided a latent image carrier that carries a latent image, a charging unit that uniformly charges the latent image carrier, a developing unit that develops the latent image on the latent image carrier, and the latent image carrier. The developing device according to claim 4 is used as the developing means in a process cartridge that integrally supports at least one means selected from cleaning means for cleaning the body and is detachable from the main body of the image forming apparatus. It is characterized by this.
According to a sixth aspect of the present invention, there is provided an image carrier, developing means for developing an electrostatic latent image formed on the image carrier, and transfer means for transferring a toner image formed on the image carrier to a transfer body. In the image forming apparatus, the developing device according to claim 4 is used as the developing means.
In the complex impedance plot, the real component of the impedance is taken on the horizontal axis and the imaginary component is taken on the vertical axis, and the locus of the impedance accompanying the frequency change is taken on this complex plane. The peak width is a resistance component that does not depend on the frequency component, and the peak height indicates a capacitance component that depends on the frequency component. The developing roller of the present invention has two peaks in this complex impedance plot, the first peak width and peak height are 10 ⁷ to 10 ⁸ Ω, 10 ⁶ to 10 ⁸ Ω, and the second peak width and The peak height is 10 ⁴ to 10 ⁷ Ω, 10 ³ to 10 ⁷ Ω. The developing roller of the present invention has an electrical two-layer structure in which resistance components differ by one digit or more, and includes a semi-insulating surface layer corresponding to the first peak and a semi-conductive base layer corresponding to the second peak. The high capacity component corresponding to the resistance component is obtained in each layer. A large capacitance component means high charging performance. A conventional general developing roller is considered to have a lower capacity component than a resistance component.
In the complex impedance plot, when the first peak width (resistance component) is less than 10 ⁷ Ω, the toner charge rising property is improved, but the toner charge level is lowered to cause scumming, and when it exceeds 10 ⁸ Ω, the charge rising property is increased. As a result, soiling will occur. When the first peak height (capacitance component) is less than 10 ⁶ Ω, the charging performance is lowered, the toner charge level is lowered, and background staining occurs. The first peak height (capacitance component) has an upper limit of 10 ⁸ Ω on the core-coll arc rule. When the second peak width (resistance component) is less than 10 ⁴ Ω, it approaches conductivity, but the workability of the material is impaired and the hardness is increased, so that it cannot be stably produced. If the second peak width (resistance component) exceeds 10 ⁷ Ω, the generation speed of the mirror image force is slowed and toner scattering increases. If the second peak height (capacitance component) is less than 10 ³ Ω, it cannot be produced stably in production. The upper limit of the second peak height (capacitance component) is 10 ⁷ Ω on the coll-coll arc rule. For the above reasons, the peak width (resistance component) and peak height (capacitance component) of two peaks in the complex impedance are defined in the above range. As a result, the toner on the developing roller can be charged up to a desired charging level at the moment of passing through the regulating portion, and the toner on the developing roller can be reliably held on the developing roller by the mirror image force. Furthermore, since the toner can be charged efficiently as described above, the regulation pressure by the regulation member can be reduced. As a result, stress on the developing roller is also reduced, and the life of the developing roller can be extended.

  According to the present invention, there is an excellent effect that it is possible to provide a developing roller having an optimal electrical characteristic in a one-component developing system, and a developing device, a process cartridge, and an image forming apparatus using the developing roller.

FIG. 2 is a configuration diagram showing a configuration of a developing device according to the present embodiment. The characteristic view which shows an example of a complex impedance plot. Explanatory drawing explaining an equivalent circuit model.

  Hereinafter, embodiments of the present invention will be described. FIG. 1 is a cross-sectional view showing a main configuration of an image forming apparatus according to the present embodiment. As shown in FIG. 1, the image forming apparatus includes a drum-shaped photosensitive member 1 as an image carrier, a developing device 2 that develops an electrostatic latent image formed on the photosensitive member 1, and the like. The photoreceptor 1 is rotationally driven in the clockwise direction in the drawing and is uniformly charged by the charging roller 3. The uniformly charged photoconductor 1 is exposed and scanned by a light beam from an optical writing unit (not shown) and carries an electrostatic latent image corresponding to image information. This electrostatic latent image is developed into a toner image by the developing device 2. The toner image developed on the photoreceptor 1 is transferred onto the intermediate transfer belt 4 and transferred onto a transfer sheet as a recording medium at a transfer unit (not shown). The transfer residual toner adhering to the photoconductor after the transfer is removed by the drum cleaning device 5.

  The developing device 2 includes a toner storage chamber 11 that stores toner, and a toner supply chamber 12 that is provided below the toner storage chamber 11. A developing roller 13, a developing roller is provided below the toner supply chamber 12. A regulating member 14 and a supply roller 15 provided in contact with the developing roller 13 through the toner on 13 are provided. The developing roller 13 is disposed in contact with the photoreceptor 2 and is applied with a predetermined developing bias from a high voltage power source (not shown). A toner stirring member 16 is provided in the toner storage chamber 11 and rotates in a counterclockwise direction. In the axial direction, the toner agitating member 16 has an area of the toner conveying surface that is rotationally driven at a portion where the tip of the toner agitating member 16 does not pass through the vicinity of the opening 17 to sufficiently flow and agitate the contained toner. Further, the portion where the tip portion passes the vicinity of the opening portion 17 has a shape in which the area of the toner conveying surface by rotational driving is reduced, thereby preventing an excessive amount of toner from being guided to the opening portion 17. . The toner in the vicinity of the opening 17 is moderately loosened by the toner stirring member 16, passes through the opening 17 by its own weight, and drops and moves to the toner supply chamber 12. The surface of the supply roller 15 is covered with a foam material having a structure having pores (cells), and the toner conveyed into the toner supply chamber 12 is efficiently attached and taken in, and the surface of the supply roller 15 is connected to the developing roller 13. Toner deterioration due to pressure concentration at the contact portion is prevented. A supply bias having a value offset in the same direction as the charging polarity of the toner is applied to the supply roller 15 with respect to the developing bias. This supply bias acts in the direction in which the precharged toner is pressed against the developing roller 13 at the contact portion with the developing roller 13. However, the offset direction is not limited to this, and the offset may be changed to 0 or the offset direction may be changed depending on the type of toner. The supply roller 15 rotates in the counterclockwise direction, and applies and supplies the toner adhered to the surface to the surface of the developing roller 13.

  The developing roller 13 rotates in the counterclockwise direction, and conveys the toner held on the surface to a position facing the regulating member 14 and the photoreceptor 1. The regulating member 14 is made of a metal leaf spring material such as SUS or phosphor bronze, and has a free end abutted against the surface of the developing roller 13 with a pressing force of 20 to 50 N / m, and passed under the pressing force. The toner is thinned and charged by triboelectric charging. Further, a regulating bias having a value offset in the same direction as the toner charging polarity with respect to the developing bias is applied to the regulating member 14 in order to assist frictional charging. The photosensitive member 1 rotates in the clockwise direction, and thus the surface of the developing roller 13 moves in the same direction as the traveling direction of the photosensitive member 1 at a position facing the photosensitive member 1. The thinned toner is conveyed to a position facing the photosensitive member 1 by the rotation of the developing roller 13, and a latent image formed by the developing bias applied to the developing roller 13 and the electrostatic latent image on the photosensitive member 1. In response to the electric field, it moves to the surface of the photoreceptor 1 and is developed. A seal 18 is provided in contact with the developing roller 13 at a portion where the toner remaining on the developing roller 13 without being developed on the photosensitive member 1 returns to the toner supply chamber 12 again. The device 2 is sealed so as not to leak.

  Next, the developing roller that is a characteristic part of the present invention will be described. The developing roller 13 has a base layer made of an elastic material such as rubber or elastomer on a metal core shaft, and a surface layer made of a material easily charged with a polarity opposite to that of the toner. The surface roughness of the developing roller is set to 0.3 to 2.0 μm in Ra, and a necessary amount of toner is held on the surface.

  Here, the toner on the developing roller 13 is charged to a desired level at the moment when it passes through the regulating portion between the developing roller 13 and the regulating member 14, and the mirror image force between the developing roller 13 and the toner. Therefore, electrical characteristics for reliably holding the toner are required. In other words, it is required to keep the charge with a certain degree of insulation while smoothing the movement of the charge. In order to achieve these, the electrical characteristics required for the developing roller 13 can be expressed by a peak shape of complex impedance.

  As for the complex impedance, the response of the developing roller 13 when the alternating current is applied while changing the frequency is examined. The response has no phase shift with respect to the applied AC voltage, and the response has a phase shift of π / 2. Measured separately. The response with no phase shift expressed by impedance is defined as Z ′, the response with shift is expressed by impedance as Z ″, and Z ′ on the X axis and Z ″ on the Y axis in the XY graph. What is shown is a complex impedance plot. In the case of a homogeneous insulator with a complex impedance plot, it is clarified in the complex-impedance plot that a semicircle having an insulator resistance R as a diameter is drawn in the complex impedance plot according to the coil-core arc rule. For example, in a developing roller having a multi-layer structure in which the surface layer and the base layer have the same electrical characteristics, the complex impedance plot shows the DC resistance component of the developing roller as the diameter as shown by the dotted line in FIG. Draw one semicircular peak. In the developing roller in which the surface layer and the base layer are electrically different, the complex impedance plot draws two peaks as shown by the solid line in FIG. Generally, when the resistance is different by one digit or more, the plot has two peaks. The complex impedance plot can be divided into peak width and height, where the peak width shows the real part, that is, the resistance component that is a frequency independent component, and the peak height depends on the imaginary part, that is, the frequency The capacitive component which is a component is shown. By using a complex impedance measurement method that allows nondestructive quantitative measurement of the electrical properties of each layer of the developing roller, which could not be measured well even by performing destructive testing so far, it can be measured and compared with other companies' products. Became.

The developing roller 13 according to the present embodiment is characterized in that the complex impedance plot when the AC voltage is applied while changing the frequency has two peaks. The first peak width and peak height are 10 ⁷ to 10 ⁸ Ω, 10 ⁶ to 10 ⁸ Ω, and the second peak width and peak height are 10 ⁴ to 10 ⁷ Ω, 10 ³ to 10 ^7. It is characterized by being Ω. That is, the developing roller 13 has a two-layer structure in which the resistance is different by one digit or more, a semi-insulating surface layer is provided on the surface of the semiconductive base layer, and a high capacity component corresponding to the resistance component is obtained in each layer. become. The conventional general developing roller is not manufactured in consideration of the capacity component, and therefore has a lower capacity component than the resistance component.

  Considering the peak width and height of this complex impedance plot as the developing roller 13, when the peak width is narrow, that is, when the DC resistance component is low, the image force generation speed is fast, and when the peak width is wide, the image force is generated. Become slow. When the generation of the mirror image force is slow, the toner holding ability is lowered, and the toner scattering from the developing roller is likely to occur. Further, when the peak height is high, that is, when the capacitance component is large, the charging performance is high, and when the peak height is low, the charging performance is low and the photoconductor soiling is likely to occur.

Specifically, when the first peak width (resistance component) corresponding to the electrical characteristics of the semi-insulating surface layer is less than 10 ⁷ Ω, the toner charge rising property is improved, but the toner charge level is lowered to cause scumming. When it exceeds 10 ⁸ Ω, the charge rising property is deteriorated and the background is also stained. When the first peak height (capacitance component) is less than 10 ⁶ Ω, the charging performance is lowered, the toner charge level is lowered, and scumming occurs. The first peak height (capacitance component) has an upper limit of 10 ⁸ Ω on the core-coll arc rule. When the second peak width corresponding to the electrical characteristics of the semi-conductive base layer (resistance component) is below 10 ^4, but closer to the conductive manufacturing hardness will be increased with impair the processability of the material stably If it cannot be produced and exceeds 10 ⁷ Ω, the generation speed of the mirror image force is slowed and toner scattering increases. If the second peak height (capacitance component) is less than 10 ³ Ω, it cannot be produced stably in production. The upper limit of the second peak height (capacitance component) is 10 ⁷ Ω on the coll-coll arc rule. For the above reasons, the peak width and peak height of two peaks in the complex impedance are defined in the above range.

  In the complex impedance plot of the developing roller 13, when the first peak width is Zs and the second peak width is Zb, Zs> Zb and 5000> Zs / Zb> 50. To do. If Zs <Zb, that is, surface layer resistance <base layer resistance, toner scattering due to a decrease in mirror image force, and photoconductor ground contamination due to a decrease in charge level occur. When Zs / Zb exceeds 5000, it is difficult to stably produce a conductive rubber base material, and when it is below 50, the conductivity of the base layer is not ensured. appear.

  As described above, the developing roller 13 having the electrical characteristics that the complex impedance plot satisfies the above conditions is charged up to a desired charging level at the moment when the toner on the developing roller 13 passes through the regulating portion between the regulating roller 14 and the developing roller 13. In addition, the toner on the developing roller is reliably held on the developing roller by the mirror image force. Further, since the toner can be charged efficiently as described above, the regulation pressure by the regulation member 14 can be reduced. As a result, the stress on the developing roller 13 is also reduced, and the life of the developing roller 13 can be extended.

  Next, specific materials used for the developing roller 13 will be described. As a metal used for the core shaft of the developing roller 13, for example, aluminum, SUS (stainless steel), iron or the like can be used. In the case of SUS, stainless steel such as 303, 304, and 416, and in the case of aluminum, aluminum of a material such as A6063, A5056, and A3003 can be used.

  Examples of the elastic material used for the base layer of the developing roller 13 include urethane rubber, chloroprene rubber, butadiene acrylonitrile, epichlorohydrin rubber, ethylene propylene rubber, natural rubber, butyl rubber, nitrile rubber, polyisoprene rubber, polybutadiene rubber, silicone rubber, One type selected from styrene-butadiene rubber, ethylene-propylene rubber, chloroprene rubber, acrylic rubber, and a mixture of two or more types thereof can be used. In particular, it is preferable to contain at least one of urethane rubber, chloroprene rubber, butadiene acrylonitrile and epichlorohydrin rubber, and a material having a JIS-hardness of 40 ° to 50 ° is preferable. Urethane rubber, chloroprene rubber, butadiene acrylonitrile, and epichlorohydrin rubber are elastic stability, chemical resistance, heat resistance as rubber, ensuring elasticity in the low elastic area required as a developing roller for contact development, processability such as surface shape From the point of view, it is preferable.

  Furthermore, a crosslinking agent and a vulcanizing agent can be added to these elastic materials in order to crosslink them into rubbery substances. In this case, a vulcanization aid, a vulcanization accelerator, a vulcanization retarder, etc. can be used in both cases of organic peroxide crosslinking and sulfur crosslinking. In addition to the above, foaming agents, plasticizers, softeners, tackifiers, tackifiers, separation agents, mold release agents, extenders, colorants, etc., which are commonly used as rubber compounding agents, have characteristics. It can add in the range which does not impair.

  The surface layer of the developing roller 13 can be obtained by performing various coatings such as dip method, spray coating, roll coating, etc. around the elastic layer. As the surface layer, charge control particles such as acrylic fine particles and nigrosine charge control material are dispersed in a crosslinkable polymer composed of a crosslinkable polymer such as isocyanate, epoxy or alkylsiloxane and a crosslinker such as alcohol, amine or silanol. Can be obtained.

  Here, adjustment of the complex impedance of the base layer and the surface layer of the developing roller 13 will be described. The resistance component of the complex impedance can be adjusted by adding the conductive material such as carbon black, the dispersion state, and the like. Conductive materials include powder, conductive carbon such as carbon black and acetylene black, carbon for rubber such as SAF, ISAF, HAF, FEF, GPF, SRF, FT, and MT, and carbon for color subjected to oxidation treatment. , Pyrolytic carbon, indium-doped tin oxide (ITO), tin oxide, titanium oxide, zinc oxide, copper, silver, germanium, and other metals and conductive polymers such as metal oxides, polyaniline, polypyrrole, polyacetylene, etc. Can do. In addition, there are ionic conductive substances as conductivity imparting agents, including inorganic ionic conductive substances such as sodium perchlorate, lithium perchlorate, calcium perchlorate, and lithium chloride, as well as modified fatty acid dimethylammonium ethosulphate, stearin. There are organic ionic conductive substances such as acid ammonium acetate, lauryl ammonium acetate, and octadecyltrimethylammonium perchlorate.

  In particular, by improving the dispersibility of the conductive material by the following method, a more uniform and relatively high resistance state can be obtained. Methanol, ethanol, isopropyl alcohol, acetone or the like is sprayed or dipped on the surface of the developing roller 13 to swell the rubber, thereby reducing the conductive material dispersion diameter of the carbon black structure or the like to make it finely dispersed. In addition, it is possible to improve the dispersibility of conductive materials by applying high shear shear due to low temperature, high throughput, etc. with a kneader, and high shear shear due to high viscosity, high rotation, etc. with a disperser such as a homogenizer. .

  The capacitance component of the complex impedance can be increased by thinning the layer, adding a ferroelectric such as barium titanate, forsterite, or strontium titanate, and further finely dispersing the conductive material. In particular, when improving the dispersibility of the conductive material by swelling, if a trace amount of alkali metal salt such as sodium chloride, potassium chloride, sodium acetate is used, a small amount of alkali metal is contained inside the rubber, resulting in further electrical A homogeneous rubber material can be obtained, and as a result, a high capacity component corresponding to the resistance can be obtained.

  Next, the toner used in the developing device 2 according to this embodiment will be described. The toner has a configuration in which inorganic fine particles as external additives are externally added to a toner base. The toner base usually contains a resin (binder resin), a colorant, a charge control agent, a release agent (wax), and other additives. The method for forming the toner base particles can be appropriately selected from known methods. Specifically, a method of forming toner base particles using a suspension polymerization method, an emulsion polymerization aggregation method, a dissolution suspension method or the like, a method of forming toner base particles while producing an adhesive substrate, Examples thereof include a pulverization method. The toner manufacturing method according to the exemplary embodiment is not limited to this, but is preferably manufactured by the following manufacturing method. At least a step of dissolving or dispersing a binder resin having at least an aromatic group-containing polyester skeleton, a colorant, and a release agent in an organic solvent, and then dispersing and granulating the solution or dispersion in an aqueous medium; Consisting of including. More specifically, it is as follows.

<Granulation process>
(Organic solvent)
As an organic solvent for dissolving or dispersing a binder resin having an aromatic group-containing polyester skeleton, a colorant and a release agent, a Hansen solubility parameter described in Volume 2, Section VII of “POLYMER HANDBOOK” 4th Edition, WILEY-INTERSCIENCE is 19 It is preferable that the boiling point is less than 100 ° C. from the viewpoint of easy removal of the solvent later. Examples of such organic solvents include 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. Particularly preferred are ester solvents such as methyl acetate and ethyl acetate, aromatic solvents such as toluene and xylene, and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride. The polyester resin, the colorant and the release agent may be dissolved or dispersed at the same time. Usually, each of them is dissolved or dispersed alone, and the organic solvents used at that time may be different or the same. The same is preferable considering the above.

(Dissolution or dispersion of binder resin having aromatic group-containing polyester skeleton)
The resin concentration or concentration of the binder resin having an aromatic group-containing polyester skeleton is preferably about 40% to 80%. If the concentration is too high, it will be difficult to dissolve or disperse, and the viscosity will be too high to handle. On the other hand, if the density is too low, the amount of toner produced decreases. When mixing a modified polyester resin having an isocyanate group at the terminal with a binder resin having an aromatic group-containing polyester skeleton, it may be mixed in the same solution or dispersion, or separately prepared in a solution or dispersion. However, considering the respective solubility and viscosity, it is preferable to prepare separate solutions or dispersions.

(Dissolution or dispersion of colorant)
The colorant may be dissolved or dispersed alone, or may be mixed in the solution or dispersion of the polyester resin. If necessary, a dispersion aid or a polyester resin may be added, or the master batch may be used.

(Dissolution or dispersion of release agent)
When dissolving or dispersing wax as a release agent, when using an organic solvent in which wax does not dissolve, it is used as a dispersion, but the dispersion is prepared by a general method. That is, an organic solvent and wax may be mixed and dispersed with a disperser such as a bead mill. Further, after mixing the organic solvent and the wax, it is sometimes possible to shorten the dispersion time by once heating to the melting point of the wax, cooling with stirring and then dispersing with a disperser such as a bead mill. Further, a plurality of waxes may be mixed and used, or a dispersion aid or a polyester resin may be added.

(Aqueous medium)
As an aqueous medium to be used, water alone may be used, but a solvent miscible with water may be used in combination. Furthermore, an organic solvent having a Hansen solubility parameter of 19.5 or less used in the oil phase may be mixed, and preferably the addition amount in the vicinity of the saturation amount with respect to water increases the emulsification or dispersion stability of the oil phase. it can. Examples of miscible solvents include alcohols (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.), and the like. The amount of the aqueous medium used relative to 100 parts by mass of the toner composition is usually 50 to 2000 parts by mass, preferably 100 to 1000 parts by mass. If the amount is less than 50 parts by mass, the dispersion state of the toner composition is poor, and toner particles having a predetermined particle size cannot be obtained. Moreover, when it exceeds 2000 mass parts, it is not economical.

(Inorganic dispersant and organic resin fine particles)
When the dissolved or dispersed toner composition is dispersed in the aqueous medium, by dispersing the inorganic dispersant or the organic resin fine particles in the aqueous medium in advance, the particle size distribution is sharpened and the dispersion is reduced. It is preferable in terms of stability. As the inorganic dispersant, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like are used. As the resin for forming the organic resin fine particles, any resin that can form an aqueous dispersion can be used, and it may be a thermoplastic resin or a thermosetting resin. Includes vinyl resin, polyurethane resin, epoxy resin, polyester resin, polyamide resin, polyimide resin, silicon resin, phenol resin, melamine resin, urea resin, aniline resin, ionomer resin, polycarbonate resin and the like. Two or more of these resins may be used in combination. Among these, a vinyl resin, a polyurethane resin, an epoxy resin, a polyester resin, and a combination thereof are preferable from the viewpoint that an aqueous dispersion of fine spherical resin particles is easily obtained.

(Method for dispersing organic resin fine particles in water)
The method of making the resin into an aqueous dispersion of fine organic resin particles is not particularly limited, and examples thereof include the following (a) to (h).
(A) In the case of a vinyl resin, a method of directly producing an aqueous dispersion of resin fine particles by a polymerization reaction such as a suspension polymerization method, an emulsion polymerization method, a seed polymerization method or a dispersion polymerization method using a monomer as a starting material .
(B) In the case of polyaddition or condensation resin such as polyester resin, polyurethane resin, epoxy resin, etc., a precursor (monomer, oligomer, etc.) or a solvent solution thereof is dispersed in an aqueous medium in the presence of a suitable dispersant, A method of producing an aqueous dispersion of resin fine particles by heating and then adding a curing agent to cure.
(C) In the case of polyaddition or condensation resin such as polyester resin, polyurethane resin, and epoxy resin, a precursor (monomer, oligomer, etc.) or a solvent solution thereof (preferably liquid) may be liquefied by heating. .) A method in which a suitable emulsifier is dissolved therein, and then water is added to perform phase inversion emulsification.
(D) A resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) can be used as a mechanical rotary type or jet type resin. A method in which resin fine particles are obtained by pulverization using a fine pulverizer and then classification, and then dispersed in water in the presence of an appropriate dispersant.
(E) A resin solution obtained by dissolving a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent, A method in which resin fine particles are obtained by spraying in the form of a mist and then dispersed in water in the presence of an appropriate dispersant.
(F) A solvent is added to a resin solution obtained by dissolving a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent. The resin fine particles are precipitated by cooling the resin solution previously dissolved in a solvent by heating, and then the solvent is removed to obtain resin fine particles, which are then dispersed in water in the presence of a suitable dispersant. Method.
(G) A resin solution obtained by dissolving a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent, A method of dispersing in an aqueous medium in the presence of an appropriate dispersant and removing the solvent by heating or decompression.
(H) In a resin solution in which a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) is dissolved in a solvent. A method of phase inversion emulsification by adding water after dissolving an appropriate emulsifier.

(Surfactant)
Further, a surfactant or the like can be used as necessary in order to emulsify and disperse the oily phase containing the toner composition in the aqueous medium. As surfactants, alkylbenzene sulfonates, α-olefin sulfonates, anionic surfactants such as 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.

  Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Examples of the anionic surfactant having a fluoroalkyl group preferably used include fluoroalkylcarboxylic 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) ) Carboxylic acid and metal salt, perfluoroalkyl carboxylic acid (C7 to C13) and its metal salt, perfluoroalkyl (C4 to C12) sulfonic acid and its metal salt, perfluorooctane sulfonic acid diethanolamide, N-propyl-N -(2-hydroxyethyl) par Fluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Can be mentioned. In addition, 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 and the like.

(Protective colloid)
Further, 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, maleic anhydride and other acids or hydroxyl group-containing (meth) acrylic monomers Bodies such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-acrylate Chloro-2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, 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, etc., or esters of compounds containing vinyl alcohol and carboxyl groups 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 imidazole, Homopolymers or copolymers such as those having a nitrogen atom such as ethyleneimine or its heterocyclic ring, polyoxyethylene, polyoxypropylene, polyoxyethylene Alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonyl phenyl ester, etc. Celluloses such as polyoxyethylene, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose and the like can be used. In addition, when an acid such as calcium phosphate salt or an alkali-soluble material is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and then washing with water. To do. It can also be removed by an operation such as degradation with an enzyme. When a dispersant is used, the dispersant can remain on the surface of the toner particles, but it is preferable from the charged surface of the toner to be removed by washing.

(Distribution method)
The dispersion method is not particularly limited, and known equipment such as a low-speed shear type, a high-speed shear type, a friction type, a high-pressure jet type, and an ultrasonic wave can be applied. In order to make the particle size of the dispersion 2 to 20 μm, a high-speed shearing type is preferable. 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 temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 20 to 80 ° C.

(Desolation)
In order to remove the organic solvent from the obtained emulsified dispersion, a known method can be used. For example, it is possible to employ a method in which the entire system is gradually heated under normal pressure or reduced pressure to completely evaporate and remove the organic solvent in the droplets.

<Extension or / and cross-linking reaction>
For the purpose of introducing a modified polyester resin having a urethane or / and urea group, when adding a modified polyester resin having an isocyanate group at the terminal and an amine capable of reacting with this, the toner composition is added to an aqueous medium. Before dispersing, amines may be mixed in the oil phase, or amines may be added to the aqueous medium. The time required for the above reaction is selected depending on the reactivity of the isocyanate group structure of the polyester prepolymer and the added amines, but is usually 1 minute to 40 hours, preferably 1 to 24 hours. The reaction temperature is usually 0 to 150 ° C, preferably 20 to 98 ° C. This reaction may be performed before the fine particle adhesion step, or may be performed simultaneously during the fine particle adhesion step. Further, it may be after the fine particle adhesion step is completed. Moreover, a well-known catalyst can be used as needed.

(Fine particle adhesion)
In order to further improve the toner characteristics, the surface modification can be performed by attaching resin fine particles to the surface of the toner base. The surface modifying material may be a known material such as polyester or styrene acrylic, but styrene acrylic is desirable from the viewpoint of improving the chargeability. Also, the production method is not particularly limited, and there are a dry method such as mechanical driving and thermal fixation, a wet method in which thermal extension is performed, and the like.

<Washing and drying process>
A known technique is used for the step of washing and drying the toner particles dispersed in the aqueous medium. That is, after solid-liquid separation with a centrifuge, a filter press, etc., the obtained toner cake is redispersed in ion-exchanged water at room temperature to about 40 ° C., and pH adjusted with acid or alkali as necessary, After removing the impurities and surfactants by repeating the process of solid-liquid separation again and again, the toner powder is obtained by drying with an air dryer, circulating dryer, vacuum dryer, vibration fluid dryer, etc. . At this time, the fine particle component of the toner may be removed by centrifugation or the like, and after drying, a desired particle size distribution can be obtained using a known classifier as necessary.

<External processing>
The obtained dried toner powder is mixed and mixed with different kinds of particles such as charge control fine particles and fluidizing agent fine particles, and mechanical impact force is applied to the mixed powder to fix and fuse on the surface. Thus, detachment of the foreign particles from the surface of the obtained composite particle can be prevented. Specific means include a method of applying an impact force to the mixture by blades rotating at high speed, a method of injecting and accelerating the mixture in a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. Henschel mixer (Mitsui Mining Co., Ltd.), super mixer (Kawata Co., Ltd.), Ong mill (Hosokawa Micron Co., Ltd.), hybridization system (Nara Machinery Co., Ltd.), Kryptron system (Earth Technica Co., Ltd.) And automatic mortar.

<Toner material>
Oil Phase Raw Material (1) Polyester Resin As the binder resin used in the toner according to this embodiment, it is preferable to use a resin having a polyester skeleton and a polyester resin not containing a vinyl polymerizable group. Examples of the polyester resin include a so-called modified polyester resin (hereinafter referred to as a modified polyester resin (A)) having a urea bond and / or a urethane bond obtained from an isocyanate group-containing polyester prepolymer and amines, and a urea bond or urethane. A known polyester resin such as an unmodified polyester resin (hereinafter referred to as an unmodified polyester resin (C)) in the sense that it does not have a bond can be used, and a single resin or a combination of two or more resins may be used.

(2) Modified Polyester Resin In the production of the binder resin for toner according to this embodiment, a polyester prepolymer having an isocyanate group can be used as a precursor of the modified polyester resin (A). Preferably, a polyester prepolymer having an isocyanate group at the terminal can be used. Moreover, the polyester prepolymer which has two or more, especially 3 or more isocyanate groups can be used. As the polyester prepolymer (A) having an isocyanate group, a polyester having a polycondensate of polyol (1) and polycarboxylic acid (2) as exemplified below and having an active hydrogen group is further added to polyisocyanate (3). And polyester resin reacted with. Examples of the active hydrogen group possessed by the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is a particularly preferred active hydrogen group.

a) Polyol Specific polyol (1) includes 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 diol (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols ( 4,4′-dihydroxybiphenyls such as bisphenol A, bisphenol F, bisphenol S, 3,3′-difluoro-4,4′-dihydroxybiphenyl, and the like; bis (3-fluoro- 4-hydroxyphenyl) methane, 1-phenyl-1,1-bis (3-fluoro-4-hydroxyphenyl) ethane, 2,2-bis (3-fluoro-4-hydroxyphenyl) propane, 2,2-bis (3,5-difluoro-4-hydroxyphenyl) propane (also known as: tetrafluorobisphenol A), 2,2-bis (3-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane, etc. Bis (hydroxyphenyl) alkanes; bis (4-hydroxyphenyl) ethers such as bis (3-fluoro-4-hydroxyphenyl) ether); alkylene oxides of the above alicyclic diols (ethylene oxide, propylene oxide, Butylene oxide, etc.) adducts; alkylene oxides (e Alkylene oxide, propylene oxide, butylene oxide, etc.) adducts. Among these, preferred polyols 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 combined use with. Furthermore, trihydric or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (trisphenol PA, phenol novolac, cresol novolac, etc.) ); Alkylene oxide adducts of the above trivalent or higher polyphenols. In addition, the said polyol can be used individually by 1 type or in combination of 2 or more types, and is not limited to the above.

b) Polycarboxylic acid Examples of specific polycarboxylic acid (2) include alkylene dicarboxylic acid (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acid (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acid (Phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, 3-fluoroisophthalic acid, 2-fluoroisophthalic acid, 2-fluoroterephthalic acid, 2,4,5,6-tetrafluoroisophthalic acid, 2,3,5 , 6-tetrafluoroterephthalic acid, 5-trifluoromethylisophthalic acid, 2,2-bis (4-carboxyphenyl) hexafluoropropane, 2,2-bis (4-carboxyphenyl) hexafluoropropane, 2,2- Bis (3-carboxyphenyl) hexafluoropropane, 2,2′-bis (tri Fluoromethyl) -4,4′-biphenyldicarboxylic acid, 3,3′-bis (trifluoromethyl) -4,4′-biphenyldicarboxylic acid, 2,2′-bis (trifluoromethyl) -3,3′- Biphenyl dicarboxylic acid, hexafluoroisopropylidenediphthalic anhydride, etc.). Among these, preferable polycarboxylic acids (2) are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Further, polycarboxylic acids having 3 or more valences include aromatic polycarboxylic acids having 9 to 20 carbon atoms (trimellitic acid, pyromellitic acid, etc.), and acid anhydrides or lower alkyl esters (methyl esters, ethyl esters) described above. , Isopropyl ester, etc.) may be used to react with polyol (1). In addition, the said polycarboxylic acid can be used individually by 1 type or in combination of 2 or more types, It is not limited to the above.

c) Ratio of polyol and polycarboxylic acid The ratio of polyol (1) and polycarboxylic acid (2) is usually 2/1 as the equivalent ratio [OH] / [COOH] of hydroxyl group [OH] and carboxyl group [COOH]. To 1/1, preferably 1.5 / 1 to 1/1, and more preferably 1.3 / 1 to 1.02 / 1.

d) Polyisocyanate Specific polyisocyanates (3) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethyl caproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, Cyclohexylmethane diisocyanate); aromatic diisocyanate (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanate (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; Those blocked with a phenol derivative, oxime, caprolactam or the like; and combinations of two or more of these.

e) Ratio of isocyanate group to hydroxyl group The polyisocyanate (3) is usually 5/1 to 1/1 / as the equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 1, preferably 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 [NCO] / [OH] is less than 1, the urea content in the modified polyester becomes low, and the hot offset resistance deteriorates. The content of the polyisocyanate (3) component in the prepolymer (A) having an isocyanate group at the terminal is usually 0.5 to 40% by mass, preferably 1 to 30% by mass, more preferably 2 to 20% by mass. It is. If it is less than 0.5% by mass, 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% by mass, the low-temperature fixability deteriorates.

f) Number of isocyanate groups in the prepolymer The average number of isocyanate groups contained per molecule in the prepolymer (A) having an isocyanate group is 1 or more, preferably 1.5 to 3, Preferably, the number is 1.8 to 2.5. If it is less than 1 per molecule, the molecular weight of the modified polyester after crosslinking and / or elongation becomes low, and the hot offset resistance deteriorates.

g) Crosslinking agent and elongation agent In the crosslinking reaction and / or elongation reaction of the prepolymer, amines can be used as the crosslinking agent and / or elongation agent. Examples of the amines (B) include a diamine (B1), a trivalent or higher polyamine (B2), an amino alcohol (B3), an amino mercaptan (B4), an amino acid (B5), and the diamine (B1) to the amino acid (B5). (B6) etc. in which the amino group is blocked.
Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, tetrafluoro-p-xylylenediamine, tetrafluoro-p-phenylenediamine, etc.); alicyclic diamines (4 , 4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, isophoronediamine, etc.); and aliphatic diamines (ethylenediamine, tetramethylenediamine, hexamethylenediamine, dodecafluorohexylenediamine, tetracosafluorododecylenediamine) Etc.). Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine, diethanolamine, 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 diamine (B1) to amino acid (B5) in which the amino group is blocked (B6) include amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) of the diamine (B1) to amino acid (B5). Examples thereof include ketimine compounds and oxazoline compounds obtained. Among these amines (B), particularly preferred are diamine (B1) and a mixture of diamine (B1) and a small amount of trivalent or higher polyamine (B2).

h) Terminator Furthermore, if necessary, the molecular weight of the modified polyester after completion of the reaction can be adjusted by using a terminator for crosslinking and / or elongation. Examples of the terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).

i) Ratio of amino group and isocyanate group The ratio of the amine group (B) to the isocyanate group is determined based on the isocyanate group [NCO] in the prepolymer (A) having an isocyanate group and the amino group [NHx in the amine group (B). ] As an equivalent ratio [NCO] / [NHx] of 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. do it. When [NCO] / [NHx] is greater than 2 or less than 1/2, the molecular weight of the urea-modified polyester (i) becomes low, and the hot offset resistance deteriorates.

(3) Unmodified Polyester Resin As the polyester-based resin and the polyester-based resin in the toner according to the present embodiment, not only the modified polyester resin (A) is used alone, but also the modified polyester resin (A) is modified. It is important to include an unmodified polyester resin (C) as a toner binder component. By using the unmodified polyester resin (C) in combination, the low-temperature fixability and the gloss when used in a full-color device are improved. Examples of the unmodified polyester resin (C) include polycondensates of the same polyol (1) and polycarboxylic acid (2) as described for the polyester component of the modified polyester resin (A), and preferable ones are also modified. The same as the polyester component of the polyester resin (A). The unmodified polyester resin (C) referred to here includes not only a completely unmodified polyester resin but also those modified with a chemical bond other than a urea bond or a urethane bond. That is, a polyester resin containing a urea bond or a urethane bond is called a modified polyester resin (A), and a polyester resin that is modified but does not contain a urea bond or a urethane bond is called an unmodified polyester resin (C). The modified polyester resin (A) and the unmodified polyester resin (C) are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, the polyester component of the modified polyester resin (A) and the unmodified polyester resin (C) preferably have similar compositions. When the modified polyester resin (A) is contained, the weight ratio of the modified polyester resin (A) to the unmodified polyester resin (C) is usually 5/95 to 75/25, preferably 10/90 to 25/75, Preferably it is 12 / 88-25 / 75, Most preferably, it is 12 / 88-22 / 78. When the weight ratio of the modified polyester resin (A) 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.

a) Molecular Weight of Unmodified Polyester Resin The peak molecular weight of the unmodified polyester resin (C) is usually 1,000 to 30,000, preferably 1,500 to 10,000, more preferably 2,000 to 8,000. is there. If it is less than 1,000, the heat-resistant storage stability deteriorates, and if it exceeds 30,000, sometimes 10,000, the low-temperature fixability deteriorates. The hydroxyl value of the unmodified polyester resin (C) is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. The acid value of the unmodified polyester resin (C) is usually 0.5 to 40, preferably 5 to 35. By having an acid value, it tends to be negatively charged. In addition, those having an acid value and a hydroxyl value exceeding these ranges are easily affected by the environment under high temperature and high humidity and low temperature and low humidity, and are liable to cause image deterioration.

(4) Colorant As the colorant according to this embodiment, 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, Antimony Zhu, Permanent Red 4R, Para Red, Fayce Red, parachlor ortho nitroaniline red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Risor 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, Thioindigo Red B, Thioindigo Maroon, Oil Red, Quinakuri Red, pyrazolone red, polyazo red, chrome vermilion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkaline blue rake, peacock blue rake, Victoria blue rake, metal-free phthalocyanine blue, phthalocyanine blue, fast sky blue , Indanthrene Blue (RS, BC), Indigo, Ultramarine, 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, La kite green lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc oxide, 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.

a) Masterbatch of Colorant The colorant used in the toner of the present invention can also be used as a masterbatch combined with a resin. The binder resin for kneading together with the master batch for the production of the master batch includes styrene such as polystyrene, poly p-chlorostyrene, polyvinyl toluene, and its substitutes in addition to the modified polyester resin and unmodified polyester resin mentioned above. Polymers of: styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-acrylic acid Ethyl copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, Styrene-α-chloromethacrylate Copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer Styrene copolymers such as polymers, styrene-maleic acid ester copolymers; 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, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. Can be mixed and used.

b) Master batch production method A master batch can be obtained by mixing and kneading a binder resin for a master batch and a colorant under high shearing force. At this time, an organic solvent can be used in order to enhance the interaction between the colorant and the resin. Also, an aqueous paste of a colorant containing water called a flushing method is mixed and kneaded together with a binder resin and an organic solvent, and the colorant is transferred to the binder resin side to remove moisture and organic solvent components. This method is preferably used because the wet cake of the colorant can be used as it is, and does not need to be dried. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used. In addition, it can be prepared and used as a dispersion / dissolution solution (wet master) of an organic solvent for oil phase in order to enhance the dispersion / solubility in the solvent during the preparation of the oil phase.

(5) Wax The toner according to the exemplary embodiment can contain a wax together with the binder resin and the colorant. As the wax, for example, known ones described in “Revised properties and applications of the second edition, supervised by Kenzo Fusegawa, Koshobo Co., Ltd.” can be used. Specific waxes include polyethylene wax and polypropylene wax. Polyolefins such as paraffin wax, paraffins such as sazol wax; trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18-octadecanediol Synthetic esters such as distearate, tristearyl trimellitic acid, distearyl maleate, octadecyl stearate; natural plant waxes such as carnauba wax, rice wax, candelilla wax; montan wax, ozokerai Include fatty acid amide synthetic wax such as natural mineral waxes and stearic acid amide, such as ceresin. Of these waxes, polyolefins, paraffins, synthetic esters, carnauba wax, and rice wax are preferable, and they can be used alone or in combination of two or more.

  The wax content in the toner can be 2 to 30% by mass, preferably 4 to 15% by mass with respect to 100% by mass of the resin component. If the amount of wax relative to the total amount of toner is less than 4%, the wax exudes on the surface of the fixing member at the time of fixing so that it does not stick to the fixing member. The hot offset margin may be lost. On the other hand, if it exceeds 15% by mass, the wax melts at a low temperature, so it is easily affected by thermal energy and mechanical energy. For example, when a low melting point wax is used, for example, adhesion to the regulating member 14 at the regulating portion. It may cause image noise. Further, the endothermic peak at the time of temperature rise measured by a differential scanning calorimeter (DSC) of the wax can fix the toner at a low temperature of 65 to 115 ° C., but if the melting point is less than 65 ° C., the fluidity becomes poor. When the temperature is higher than 115 ° C., the fixability tends to deteriorate.

a) Wax dispersant In order to make the wax exist in the vicinity of the toner particle surface, the wax dispersant is controlled. As the wax dispersant, a monomer for a toner binder that is less compatible with water at the time of emulsification of the toner and the polymerization reaction product is incompatible with the wax or poorly compatible with the wax is preferably used. By adding 50 to 200% to the wax and dispersing and polymerizing the wax, the toner particles can be controlled to exist in the vicinity of the particle surface. A monomer for a general toner binder can be used for the toner binder that is not easily compatible. Specifically, styrene monomers [styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene, p-methoxystyrene, p-hydroxystyrene, p-acetoxystyrene, vinyltoluene, ethylstyrene, phenylstyrene, Benzyl styrene, etc.], unsaturated carboxylic acid alkyl (1-18 carbon atoms) ester [methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, etc.], vinyl ester Monomers such as vinyl acetate, vinyl ether monomers such as vinyl methyl ether, halogen-containing vinyl monomers such as vinyl chloride, diene monomers such as butadiene and isobutylene, (meth) acrylonitrile, cyanostyrene, etc. Tolyl monomers and combination thereof. When the wax is finely dispersed by wet pulverization, it is preferable to add a wax dispersant in order to improve dispersibility. There is no restriction | limiting in particular as such a wax dispersing agent, According to the objective, it can select suitably. The basic concept for selecting the wax dispersant may be a material having a part having a high affinity for wax and a part having a high affinity for binder resin. For example, a polyethylene wax grafted with a styrene- (meth) acrylic ester copolymer is preferably used. There is no restriction | limiting in particular in content with respect to the toner of this wax dispersing agent, According to the objective, it can select suitably, For example, 1-200 mass parts is preferable with respect to 100 mass parts of total addition amount of wax.

(2) Radical generator A radical generator is added to the aqueous medium. The radical generator added to the aqueous medium is not particularly limited as long as it is dispersed or dissolved in the aqueous medium. It may be a single or a combination of two or more, or a combination of an oxidizing agent and a reducing agent utilizing an oxidation-reduction reaction. The addition amount of the radical generator is adjusted by the radical generator type and the granulation temperature with respect to the toner solid content, and is usually 0.1 to 20% by mass, preferably 0.5 to 10% by mass. . As the radical generator, those known as so-called polymerization initiators can be used. Examples thereof include polymerization initiators described in Volume 1, Section II of “POLYMER HANDBOOK” 4th Edition, WILEY-INTERSCIENCE. The radical generator can be added to the oil phase or / and the water phase. When adding to the oil phase, it is preferable to use an oil-soluble polymerization initiator. When adding to the water phase, a water-soluble polymerization initiator is added. It is preferable to do this.

  Specific examples of the oil-soluble polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane- 1-carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azo or diazo polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, Diisopropyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis- (4 , 4-t-butylperoxycyclohexyl) propane, Lys - the (t-butylperoxy) peroxide polymerization initiator or a peroxide such as triazine can be mentioned polymeric initiators having a side chain.

  Examples of the water-soluble polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, 2,2′-azobis (2-methylpropionamidine dihydrochloride), 2,2′-azobis [N- (2 -Carboxyethyl) -2-methylpropionamidine], 4,4′-azobis (4-cyanovaleric acid) azobisaminodipropane acetate, azobiscyanovaleric acid and its salts, hydrogen peroxide, and the like. .

(3) Inorganic Dispersant A dissolved or dispersed toner composition is dispersed in an aqueous medium in the presence of an inorganic dispersant or resin fine particles. As the inorganic dispersant, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like are used. Use of a dispersant is preferable in that the particle size distribution becomes sharp and the dispersion is stable.

(4) Resin Fine Particles It is preferable to add resin fine particles to the toner according to the exemplary embodiment separately from the binder resin. As the resin for forming the resin fine particles, any resin can be used as long as it can form a dispersion in an aqueous medium, and a dispersion of fine spherical resin particles is preferable. The resin fine particles may be a thermoplastic resin or a thermosetting resin. For example, vinyl resin, polyurethane resin, epoxy resin, polyester resin, polyamide resin, polyimide resin, silicon resin, phenol resin, Examples thereof include melamine resin, urea resin, aniline resin, ionomer resin, polycarbonate resin and the like. Two or more of these resins may be used in combination. Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferable from the viewpoint that a dispersion of fine spherical resin particles is easily obtained. These resins will be described below.

a) Vinyl Resin A vinyl resin is a polymer obtained by homopolymerizing or copolymerizing a vinyl monomer. Examples of the vinyl monomer include the following compounds (a) to (j).
(A) vinyl hydrocarbon aliphatic vinyl hydrocarbon: alkenes such as ethylene, propylene, butene, isobutylene, pentene, heptene, diisobutylene, octene, dodecene, octadecene, α-olefins other than the above, etc .; alkadienes Such as butadiene, isoprene, 1,4-pentadiene, 1,6-hexadiene, 1,7-octadiene and the like.
Alicyclic vinyl hydrocarbons: mono- or di-cycloalkenes and alkadienes such as cyclohexene, (di) cyclopentadiene, vinylcyclohexene, ethylidenebicycloheptene, etc .; terpenes such as pinene, limonene, indene and the like.
Aromatic vinyl hydrocarbons: Styrene and its hydrocarbyl (alkyl, cycloalkyl, aralkyl and / or alkenyl) substitutions such as α-methylstyrene, vinyltoluene, 2,4-dimethylstyrene, ethylstyrene, isopropylstyrene, Butyl styrene, phenyl styrene, cyclohexyl styrene, benzyl styrene, crotyl benzene, divinyl benzene, divinyl toluene, divinyl xylene, trivinyl benzene, etc .; and vinyl naphthalene, etc.
(B) Carboxyl group-containing vinyl monomers and salts thereof C3-C30 unsaturated monocarboxylic acids, unsaturated dicarboxylic acids and anhydrides and monoalkyl (C1-C24) esters thereof such as (meth) acrylic Acid, (anhydrous) maleic acid, maleic acid monoalkyl ester, fumaric acid, fumaric acid monoalkyl ester, crotonic acid, itaconic acid, itaconic acid monoalkyl ester, itaconic acid glycol monoether, citraconic acid, citraconic acid monoalkyl ester, Carboxylic acid-containing vinyl monomers such as cinnamic acid.
(C) Sulfone group-containing vinyl monomers, vinyl sulfate monoesters and their salts, alkene sulfonic acids having 2 to 14 carbon atoms, such as vinyl sulfonic acid, (meth) allyl sulfonic acid, methyl vinyl sulfonic acid, styrene sulfone Acid; and alkyl derivatives thereof having 2 to 24 carbon atoms such as α-methylstyrene sulfonic acid; sulfo (hydroxy) alkyl- (meth) acrylate or (meth) acrylamide, such as sulfopropyl (meth) acrylate, 2-hydroxy -3- (meth) acryloxypropylsulfonic acid, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid, 2- (meth) acryloyloxyethanesulfonic acid, 3- (meth) acryloyloxy-2- Hydroxypropane sulfonic acid, 2- (meth) Kurylamido-2-methylpropanesulfonic acid, 3- (meth) acrylamide-2-hydroxypropanesulfonic acid, alkyl (3 to 18 carbon atoms) allylsulfosuccinic acid, poly (n = 2 to 30) oxyalkylene (ethylene, propylene, Butylene: single, random or block) mono (meth) acrylate sulfate [poly (n = 5-15) oxypropylene monomethacrylate sulfate, etc.], polyoxyethylene polycyclic phenyl ether sulfate, etc.
(D) Phosphoric acid group-containing vinyl monomers and salts thereof (meth) acryloyloxyalkyl phosphate monoesters such as 2-hydroxyethyl (meth) acryloyl phosphate, phenyl-2-acryloyloxyethyl phosphate, (meth) acryloyloxyalkyl (C1-24) Phosphonic acids such as 2-acryloyloxyethylphosphonic acid; and salts thereof.
Examples of the salts of the compounds (b) to (d) include alkali metal salts (sodium salts, potassium salts, etc.), alkaline earth metal salts (calcium salts, magnesium salts, etc.), ammonium salts, amine salts, or A quaternary ammonium salt etc. are mentioned.
(E) Hydroxyl group-containing vinyl monomer hydroxystyrene, N-methylol (meth) acrylamide, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, (meth) allyl alcohol, crotyl Alcohol, isocrotyl alcohol, 1-buten-3-ol, 2-buten-1-ol, 2-butene-1,4-diol, propargyl alcohol, 2-hydroxyethylpropenyl ether, sucrose allyl ether, and the like.
(F) Nitrogen-containing vinyl monomers Amino group-containing vinyl monomers: aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, t-butylaminoethyl methacrylate, N-aminoethyl (meta ) Acrylamide, (meth) allylamine, morpholinoethyl (meth) acrylate, 4-vinylpyridine, 2-vinylpyridine, crotylamine, N, N-dimethylaminostyrene, methyl-α-acetaminoacrylate, vinylimidazole, N-vinylpyrrole , N-vinylthiopyrrolidone, N-arylphenylenediamine, aminocarbazole, aminothiazole, aminoindole, aminopyrrole, aminoimidazole, aminomercaptothiazole, etc. Luo salts, and the like. Amide group-containing vinyl monomers: (meth) acrylamide, N-methyl (meth) acrylamide, N-butyl acrylamide, diacetone acrylamide, N-methylol (meth) acrylamide, N, N-methylene-bis (meth) acrylamide, cinnamon Acid amide, N, N-dimethylacrylamide, N, N-dibenzylacrylamide, methacrylformamide, N-methyl-N-vinylacetamide, N-vinylpyrrolidone and the like. Nitrile group-containing vinyl monomers: (meth) acrylonitrile, cyanostyrene, cyanoacrylate, and the like. Quaternary ammonium cationic group-containing vinyl monomers: tertiary amine group-containing vinyl monomers such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylamide, diethylaminoethyl (meth) acrylamide and diallylamine Monomer quaternized product (quaternized with a quaternizing agent such as methyl chloride, dimethyl sulfate, benzyl chloride, dimethyl carbonate). Nitro group-containing vinyl monomers: nitrostyrene and the like.
(G) Epoxy group-containing vinyl monomers glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, p-vinylphenylphenyl oxide and the like.
(H) Vinyl ester, vinyl (thio) ether, vinyl ketone, vinyl sulfone vinyl ester; vinyl acetate, vinyl butyrate, vinyl propionate, vinyl butyrate, diallyl phthalate, diallyl adipate, isopropenyl acetate, vinyl methacrylate, methyl-4 -Vinyl benzoate, cyclohexyl methacrylate, benzyl methacrylate, phenyl (meth) acrylate, vinyl methoxyacetate, vinyl benzoate, ethyl-α-ethoxy acrylate, alkyl (meth) acrylate having 1 to 50 carbon atoms [methyl (meth) Acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl ( Acrylate), hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, eicosyl (meth) acrylate, etc.], dialkyl fumarate (two alkyl groups are linear, branched or fatty acids having 2 to 8 carbon atoms) Cyclic alkyl groups), dialkyl maleates (two alkyl groups are straight, branched or alicyclic groups having 2 to 8 carbon atoms), poly (meth) allyloxyalkanes [Dialyloxyethane, triaryloxyethane, tetraallyloxyethane, tetraallyloxypropane, tetraallyloxybutane, tetrametaallyloxyethane, etc.] and other vinyl monomers having a polyalkylene glycol chain [polyethylene glycol (molecular weight 300) ) Mono (meth) acrylate, polypropylene glycol (molecular weight 500) monoac Relate, methyl alcohol ethylene oxide 10 mol adduct (meth) acrylate, lauryl alcohol ethylene oxide 30 mol adduct (meth) acrylate, etc.], poly (meth) acrylates [poly (meth) acrylate of polyhydric alcohols: ethylene glycol Di (meth) acrylate, propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, polyethylene glycol di (meth) acrylate, etc.].
Vinyl (thio) ether; vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, hinyl butyl ether, vinyl-2-ethylhexyl ether, vinyl phenyl ether, vinyl-2-methoxyethyl ether, methoxybutadiene, vinyl-2-butoxyethyl Ether, 3,4-dihydro-1,2-pyran, 2-butoxy-2′-vinyloxydiethyl ether, vinyl-2-ethylmercaptoethyl ether, acetoxystyrene, phenoxystyrene and the like.
Vinyl ketone; vinyl methyl ketone, vinyl ethyl ketone, vinyl phenyl ketone and the like.
Vinyl sulfone; divinyl sulfide, p-vinyl diphenyl sulfide, vinyl ethyl sulfide, vinyl ethyl sulfone, divinyl sulfone, divinyl sulfoxide, and the like.
(I) Other vinyl monomers isocyanate ethyl (meth) acrylate, m-isopropenyl-α, α-dimethylbenzyl isocyanate and the like.
(J) Fluorine atom element-containing vinyl monomer 4-fluorostyrene, 2,3,5,6-tetrafluorostyrene, pentafluorophenyl (meth) acrylate, pentafluorobenzyl (meth) acrylate, perfluorocyclohexyl (meth) acrylate, Perfluorocyclohexylmethyl (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate 2,2,3,3-tetrafluoropropyl (meth) acrylate, 1H, 1H, 4H-hexafluorobutyl (meth) acrylate 1H, 1H, 5H-octafluoropentyl (meth) acrylate, 1H, 1H, 7H-dodecafluoroheptyl (meth) acrylate, perfluorooctyl (meth) acrylate, 2-perfluorooctylethyl (meth) Chryrate, heptadecafluorodecyl (meth) acrylate, trihydroperfluoroundecyl (meth) acrylate, perfluoronorbornylmethyl (meth) acrylate, 1H-perfluoroisobornyl (meth) acrylate 2- (N-butylperfluorooctanesulfonamide ) Ethyl (meth) acrylate, 2- (N-ethylperfluorooctanesulfonamido) ethyl (meth) acrylate, and corresponding compounds derived from α-fluoroacrylic acid. Bis-hexafluoroisopropyl itaconate, bis-hexafluoroisopropyl maleate, bis-perfluorooctyl itaconate, bis-perfluorooctyl maleate, bis-trifluoroethyl itaconate, bis-trifluoroethyl maleate and the like. Vinyl heptafluorobutyrate, vinyl perfluoroheptanoate, vinyl perfluorononanoate, vinyl perfluorooctanoate and the like.

b) Vinyl-based copolymer As a copolymer of vinyl-based monomers, two or more kinds of any of the above-mentioned compounds (a) to (j) are copolymerized at an arbitrary ratio. For example, styrene- (meth) acrylic acid ester copolymer, styrene-butadiene copolymer, (meth) acrylic acid-acrylic acid ester copolymer, styrene-acrylonitrile copolymer, styrene-anhydrous Maleic acid copolymer, styrene- (meth) acrylic acid copolymer, styrene- (meth) acrylic acid, divinylbenzene copolymer, styrene-styrenesulfonic acid- (meth) acrylic acid ester copolymer, and the like. . When introducing fluorine into the resin fine particles, one or more kinds of arbitrary monomers among the compounds (a) to (j) are copolymerized at an arbitrary ratio.

c) Monomer ratio of vinyl-based resin In order for the resin to form resin fine particles in the dispersion, it is necessary that the resin is not completely dissolved in water at least under the conditions for forming the dispersion. Therefore, when the vinyl resin is a copolymer, the ratio of the hydrophobic monomer to the hydrophilic monomer constituting the vinyl resin is generally 10% or more of the hydrophobic monomer, although it depends on the type of monomer selected. It is preferable that it is 30% or more. When the ratio of the hydrophobic monomer is 10% or less, the vinyl resin becomes water-soluble, and the toner particle size uniformity is impaired. Here, the hydrophilic monomer means a monomer that dissolves in water at an arbitrary ratio, and the hydrophobic monomer means another monomer (a monomer that is not substantially in a homogeneous phase with water).

<Toner fluidizer>
As a fluidizing agent for assisting the fluidity and developability of the toner, inorganic fine particles can be preferably used. The primary particle diameter of the inorganic fine particles is preferably 5 μm to 100 μm, and particularly preferably 5 μm to 50 μm. The use ratio of the inorganic fine particles is preferably 0.1 to 5.0% by mass of the toner, and particularly preferably 0.5 to 3.0% by mass. 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, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.

  Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples. First, a method for producing the developing rollers of Examples 1 to 6 and Comparative Examples 1 to 3 will be described.

[Example 1]
An NBR rubber having the following composition was cross-extruded around a SUS cored bar having a diameter of 6 mm, and then steam vulcanized at 150 ° C./50 minutes. Thereafter, an elastic base layer having a thickness of 3 mm was obtained by adjusting the diameter to 12 mm by external diameter grinding.
(Base layer composition)
NBR rubber (product name: DN401, manufactured by Nippon Zeon Co., Ltd.) ... 100 parts by weight carbon black (product name: Ketjen Black EC, manufactured by Ketjen Black International) ... 7 parts by weight calcium carbonate ... 5 weights 2 parts by weight vulcanizing agent (sulfur) ... 1 part by weight As a surface layer on the surface of this NBR elastic layer, acrylic polyol (trade name; RX-2A, manufactured by Ohashi Chemical Co., Ltd.) 80 parts by weight , 20 parts by weight of a polyisocyanate (manufactured by Nippon Polyurethane Co., Ltd., trade name: Coronate L) and 20 parts of carbon black (trade name: Toka Black # 7360SB, manufactured by Tokai Carbon Co., Ltd.) are made of a 10% solid content solution dissolved in methyl ethyl ketone. The surface treatment liquid was applied by spray coating and baked at 150 ° C. for 1 hour. This was immersed in a 0.02% sodium chloride / ethyl alcohol solution at 25 ° C. for 30 seconds and then dried to obtain a developing roller (Example 1).

[Example 2]
As an additive for the surface layer material, 3 parts of barium titanate was newly added, and 10 parts by weight of carbon black (Ketjen Black International, trade name: Ketjen Black EC) was added. A developing roller (Example 2) was obtained in the same manner as in Example 1 except that 0.04% potassium chloride was used instead of 0.02% sodium chloride as the surface treatment material.

[Example 3]
The surface of the developing roller 2 is subjected to the same surface treatment as that of the developing roller 2, except that an epichlorohydrin rubber having the following composition is cross-extruded as an elastic base layer around a SUS cored bar having a diameter of 6 mm and then heat vulcanized at 160 ° C. for 1 hour. (Example 3) was obtained.
(Base layer composition)
Epichlorohydrin rubber (manufactured by Nippon Zeon Co., Ltd., trade name: 3106) ... 100 parts carbon black (Ketjen Black International Co., Ltd., trade name: Ketjen Black EC) ... 15 parts by weight Calcium carbonate ... 7 parts by weight Vulcanization accelerator: 3 parts by weight Sulfur: 1 part by weight

[Example 4]
A developing roller (Example 4) was obtained in the same manner as in Example 2 except that 3 parts by weight of carbon black (trade name; Ketjen Black EC) added to the base layer material was used.

[Example 5]
A urethane elastomer composition having the following composition was coated around the core shaft of SUS having a diameter of 6 mm to which an adhesive had been applied in advance by a one-shot method to form a urethane elastomer layer. A developing roller (Example 5) was obtained in the same manner as in Example 2 except that the urethane elastomer layer was made to have a diameter of 12 mm by external diameter grinding to obtain a urethane elastic base layer having a thickness of 3 mm.
(Base layer composition)
Polyether-based polyol (trade name; Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.) ... 100 parts by weight carbon black (trade name: Ketjen Black EC) ... 10 parts by weight diphenylmethane diisocyanate ... 25 parts by weight

[Example 6]
A developing roller (Example 6) was obtained in the same manner as in Example 3 except that the amount of carbon black (trade name; Ketjen Black EC) added to the base layer material was 20 parts by weight.

[Comparative Example 1]
An uncured liquid silicone rubber (trade name: KE-951U, manufactured by Shin-Etsu Chemical Co., Ltd.) in which 3 parts by weight of carbon black (trade name; Ketjen Black EC) was blended around a SUS core metal having a diameter of 6 mm was filled. Thereafter, it was cured by heating at 160 ° C. for 50 minutes in a heating furnace. Then, the base layer which consists of silicone rubber 3mm thick was obtained by setting it as diameter 12mm by outer diameter grinding. On this base layer, a solid content obtained by dissolving 20 parts by weight of polyisocyanate (product name: Coronate L) manufactured by Nippon Polyurethane Co., Ltd. and 10 parts by weight of carbon black (product name: Toka Black # 7360SB, manufactured by Tokai Carbon Co., Ltd.) with methyl ethyl ketone. A surface treatment liquid consisting of a 10% solution was applied by spray coating, and baked at 150 ° C. for 1 hour to obtain a developing roller (Comparative Example 1).

[Comparative Example 2]
A developing roller (Comparative Example 2) was obtained in the same manner as in Example 2 except that the amount of carbon black added to the surface layer material was 1 part by weight.

[Comparative Example 3]
A developing roller (Comparative Example 3) was obtained in the same manner as Comparative Example 1 except that the amount of carbon black (trade name; Ketjen Black EC) added to the base layer was 1 part by weight.

Next, a method for producing toner used in the above examples and comparative examples will be described.
<Preparation of pigment / wax dispersion (oil phase)>
A container equipped with a stir bar and a thermometer was charged with 378 parts by weight of [Polyester 1] shown below, 120 parts by weight of paraffin wax (HNP9), and 1450 parts by weight of ethyl acetate. This was maintained for 5 hours and then cooled to 30 ° C. in 1 hour. Next, 500 parts by weight of [Masterbatch 1] and 500 parts by weight of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Material solution 1]. 1500 parts of this [raw material solution 1] is transferred to a container, and using a bead mill (manufactured by IMEX; Ultra Visco Mill), a liquid feed speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and a volume of 0.5 mm zirconia beads are 80 volumes. The carbon black and the wax were dispersed under the conditions of% filling and 3 passes. Next, 655 parts by weight of a 65% ethyl acetate solution of [Polyester 1] was added, and one pass was performed with a bead mill under the above conditions to obtain [Pigment / Wax Dispersion 1]. Ethyl acetate was added and adjusted so that the solid content concentration of [Pigment / Wax Dispersion 1] (130 ° C., 30 minutes) was 50%.

(Synthesis method of polyester 1)
The following materials are put in a reaction vessel, reacted at normal pressure 220 ° C. for 7 hours and reacted at a reduced pressure of 10 to 15 mmHg for 5 hours, then added 46 parts by weight of trimellitic anhydride and reacted at normal pressure 180 ° C. for 2 hours. Thus, polyester 1 was obtained.
Bisphenol A ethylene oxide 2-mole adduct ... 553 parts by weight Bisphenol A propylene oxide 2-mole adduct ... 196 parts by weight Terephthalic acid ... 220 parts by weight Adipic acid ... 45 parts by weight Dibutyltin oxide ... 2 parts by weight

<Preparation of aqueous phase>
953 parts by weight of ion-exchanged water, 88 parts by weight of a 25 wt% aqueous dispersion of organic resin fine particles for dispersion stabilization (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt), 90 parts by weight of a 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries) and 113 parts by weight of ethyl acetate were mixed and stirred to obtain a milky white liquid. This is designated as [Aqueous Phase 1].

<Emulsification process>
[Pigment / Wax Dispersion 1] 967 parts by weight, layered inorganic mineral (manufactured by Southern Clay Products, trade name: Kraton APA) 2% (toner solid equivalent), 6 parts by weight of isophoronediamine as amines, TK The mixture was mixed at 5,000 rpm for 1 minute with a homomixer (manufactured by Tokushu Kika Co., Ltd.). Thereafter, 137 parts by weight of [Prepolymer 1] shown below was added and mixed with a TK homomixer at a rotational speed of 5,000 rpm for 1 minute, then 1200 parts by weight of [Aqueous Phase 1] was added, and the rotational speed of 8 with a TK homomixer. The mixture was mixed for 20 minutes while adjusting at 1,000 to 13,000 rpm to obtain [Emulsion slurry 1].

(Method for synthesizing Prepolymer 1)
The following materials were placed in a reaction vessel, reacted at normal pressure 220 ° C. for 7 hours, and reacted at a reduced pressure of 10 to 15 mmHg for 5 hours to obtain Prepolymer 1.
Bisphenol A ethylene oxide 2-mole adduct ... 682 parts by weight Bisphenol A propylene oxide 2-mole adduct ... 81 parts by weight Terephthalic acid ... 283 parts by weight Trimellitic anhydride ... 22 parts by weight Dibutyltin oxide .. 2 parts by weight

<Desolvent>
[Emulsion slurry 1] was put into a container equipped with a stirrer and a thermometer, and the solvent was removed at 30 ° C. for 8 hours to obtain [Dispersion slurry 1].

<Particle adhesion process>
1.6 parts by weight of sodium dodecyl sulfate and 492 parts by weight of ion exchange water were placed in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, heated to 80 ° C., and then 2.5 parts by weight of potassium persulfate. Was dissolved in 100 parts by weight of ion-exchanged water. 15 minutes later, a mixture of 152 parts by weight of styrene monomer, 38 parts by weight of butyl acrylate, 10 parts by weight of methacrylic acid, and 3.5 parts by weight of n-octyl mercaptan was added dropwise over 90 minutes, and then kept at 80 ° C. for 60 minutes. It was. Thereafter, the mixture was cooled to obtain a dispersion of [vinyl copolymer resin fine particles V-1]. The solid content concentration of this dispersion was measured and found to be 25%. The average particle size of the fine particles was 50 nm. The dispersion was taken in a small petri dish, and the solid obtained by evaporating the dispersion medium was measured. The number average molecular weight was 11,000, the weight average molecular weight was 18000, and Tg was 65 ° C. To [Dispersion Slurry 1], 252 parts by weight of a dispersion of vinyl copolymer resin fine particles was added and heated to 65 ° C. over 30 minutes. A solution prepared by dissolving 10 parts by weight of magnesium chloride hexahydrate in 10 parts by weight of ion-exchange water was kept at 65 ° C. while adding little by little. After confirming that almost all of the fine particles had adhered, an aqueous hydrochloric acid solution was added to adjust the pH to 5. Then, it heated at 80 degreeC. After cooling for 2 hours, [Dispersion Slurry 1-2] was obtained.

<From washing to drying>
[Dispersion slurry 1-2] After filtering 100 parts by weight under reduced pressure,
(1): 100 parts by weight of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 900 parts by weight of ion-exchanged water was added to the filter cake of (1), ultrasonic vibration was applied, and the mixture was mixed with a TK homomixer (30 minutes at a rotation speed of 12,000 rpm), and then filtered under reduced pressure. This operation was repeated so that the electric conductivity of the reslurry liquid was 10 μC / cm or less.
(3): 10% hydrochloric acid was added so that the reslurry solution of (2) had a pH of 4, and the mixture was directly filtered with a three-one motor for 30 minutes.
(4): 100 parts by weight of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (10 minutes at a rotation speed of 12,000 rpm), and then filtered. This operation was repeated so that the reslurry liquid had an electric conductivity of 10 μC / cm or less to obtain [Filter Cake 1]. This [filter cake 1] was dried at 45 ° C. for 48 hours in a circulating drier and sieved with a mesh of 75 μm to obtain [Toner Base 1]. This [Toner Base 1] had a volume average particle diameter (Dv) of 5.0 μm, a number average particle diameter (Dp) of 4.8 μm, Dv / Dp of 1.04, and an average circularity of 0.980. . Subsequently, 100 parts by weight of [Toner Base 1] was mixed with 1.5 parts by weight of hydrophobic silica using a Henschel mixer to obtain a toner.

  Next, in order to evaluate the electrical characteristics of the developing rollers (Examples 1 to 6, Comparative Examples 1 to 3), the complex impedance of the developing roller was measured with a dielectric measurement system 126096W manufactured by Solartron. An electrode is attached to the developing roller mandrel and the roller surface, a load is applied to the electrode on the roller surface, and the measurement is started in a state where the electrode is pressed 0.3 mm. The complex impedance plot is obtained by changing the frequency from 1 M to 1 mHz with the output Vpp being 1 V. A complex impedance plot is a graph obtained by using the response with no phase shift with respect to the applied AC voltage as the real part impedance as the X axis and the response with the phase shift of π / 2 as the imaginary part impedance as the Y axis. .

The peak width and peak height in the complex impedance plot are derived by the following methods using waveform analysis software ZPLOT manufactured by Solartron.
(1) As an equivalent circuit model, as shown in FIG. 3, an RC parallel circuit is serially arranged. In FIG. 3, Rs is a measurement circuit resistance.
(2) Enter temporary values for each R component and C component of the equivalent circuit. (Since it is a temporary value, it may be an approximate value. For example, in the case of the present invention, input 10 ^{6 for} the R component and 10 ^{−9 for} the C component.)
(3) Specifying the data range to be analyzed (designating the frequency range because the data corresponds to the frequency) starts fitting.
(4) The calculated value after fitting is displayed in a cell with a temporary value, and the fitting curve based on the calculated value after fitting is displayed on the graph. . Here, the R component is the peak width. The peak height is read directly from the Cole-Cole plot. If both data do not overlap, change the temporary value by about half a digit and recalculate.

Next, the developing rollers (Examples 1 to 6 and Comparative Examples 1 to 3) were incorporated into a color laser printer IPSIO C220 manufactured by Ricoh, and image evaluation was performed. Evaluation items and evaluation criteria are shown below. The results are shown in Table 1.
(1) Photoreceptor background smear: Measures the amount of toner adhering to the photoreceptor during solid white development after running a continuous 5% yield image on 2000 sheets and developing it in a HH environment (35 ° C, 85% RH). To do. When the toner adhesion amount of 0.01 g / ^{m 2} or less and ◎, in the case of 0.03 g / ^{m 2} or less as ○, the case of 0.07 g ^{/ m} 2 2 The following is a △, 0.08 g In the case of / m ² or more, it is x.
(2) Toner scattering: after running 2000 sheets of 5% yield images continuously, in the same mode in HH environment (35 ° C, 85% RH), to the lower side of the regulating member during running (lower side relative to the rotation direction) Measure the toner adhesion amount. When the toner adhesion amount is 0.1 g or less, ◎, when it is 0.3 g or less, ◯, when it is 0.7 g or less, Δ, and when it is 0.8 g or more, ×.

From the results in Table 1, it can be seen that in the printer using the developing roller (Examples 1 to 6), it was possible to obtain a generally good quality image. These developing rollers (Examples 1 to 6) have a first peak width and a peak height of 10 ⁷ to 10 ⁸ Ω, 10 ⁶ to 10 ⁸ Ω, and a second peak width and a peak height of 10 7. It is in the range of ⁴ to 10 ⁷ Ω, 10 ³ to 10 ⁷ Ω. In particular, when the first peak width is Zs and the second peak width is Zb, the developing roller (Examples 2, 3, 5, 6) with 5000> Zs / Zb> 50 has high quality. It can be seen that a good image was obtained. On the other hand, in the developing rollers (Comparative Examples 1 to 3) in which the peak width and the peak height are out of the above ranges, the photosensitive member scumming due to the lowering of the charge level and the toner scattering due to the lowering of the mirror image force were observed.

As described above, according to the developing roller of the present embodiment, the complex impedance plot has two peaks, and the first peak width and peak height are 10 ⁷ to 10 ⁸ Ω, 10 ⁶ to 10 ⁸ Ω, The second peak width and peak height are adjusted within the range of 10 ⁴ to 10 ⁷ Ω, 10 ³ to 10 ⁷ Ω. As a result, the toner on the developing roller 13 is charged up to a desired charging level at the moment of passing through the regulating member 14, and the toner on the developing roller 13 is reliably held on the developing roller 13 by the mirror image force. It becomes possible. Further, since the toner can be charged efficiently as described above, the regulating pressure by the regulating member 14 can be reduced, the stress on the developing roller 13 can be reduced, and the life of the developing roller 13 can be extended. it can.
Further, according to the developing roller 13 according to the present embodiment, in the complex impedance plot, when the first peak width is Zs and the second peak width is Zb, Zs> Zb and 5000> Zs / Zb> 50. It is. Thereby, the said effect can be acquired reliably.
Further, according to the developing roller 13 according to this embodiment, the material constituting the base layer includes at least one of urethane rubber, chloroprene rubber, butadiene acrylonitrile, and epichlorohydrin rubber, and has a JISA hardness of 40 ° to 50 °. Has a hardness of °. Use of these rubber types is preferable from the viewpoints of elastic stability as rubber, chemical resistance, heat resistance, ensuring elasticity in a low elastic region necessary for a developing roller for contact development, processability such as surface shape, and the like.
Further, according to the developing device 2 according to the present embodiment, since the developing roller 13 is used, the occurrence of photoconductor background contamination and toner scattering is suppressed, and a high-quality image can be stably obtained. .
The developing roller 13 according to the present embodiment has a two-layer configuration in which two layers of a base layer and a surface layer are formed on a core metal, but the present invention is not necessarily limited to a two-layer configuration. A layer configuration having electrical characteristics having two peaks in the complex impedance plot may be used. For example, a multilayer configuration in which an intermediate layer is formed between the base layer and the surface layer may be used. In the case where the mechanical adhesion between the surface layer and the base layer is weak or the hardness is greatly different, an intermediate layer may be provided to provide flexibility. The intermediate layer can be formed by a manufacturing method that is the same as the surface layer, such as coating → firing. Examples of the material for the intermediate layer include NBR, hydrogenated acrylonitrile-butadiene rubber (H-NBR), polyurethane-based elastomer, CR, natural rubber, BR, IIR, etc., and can be appropriately selected according to the purpose of use. it can.
In addition to the image forming apparatus that transfers the toner image on the photosensitive member to the intermediate transfer member and then transfers the toner image on the intermediate transfer member to the transfer paper, the developing device according to the present embodiment is not illustrated. Also, it can be mounted on an image forming apparatus or the like that directly transfers a toner image formed on a photoconductor onto a transfer sheet. Further, even in a monochrome image forming apparatus having one photosensitive member and one developing device, a toner image for each color is sequentially formed on one photosensitive member, and each color toner image on the photosensitive member is sequentially transferred to an intermediate transfer member. Alternatively, it may be a color image forming apparatus that transfers images superimposed on transfer paper. Further, for example, a plurality of image forming units including photoconductors are arranged side by side, toner images of different colors are formed on the photoconductors of the image forming units, and the toner images on the photoconductors are transferred to an intermediate transfer body or transfer paper. It may be a tandem type color image forming apparatus that superimposes and transfers the image.

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Developing device 3 Charging roller 4 Intermediate transfer belt 5 Cleaning device 11 Toner storage chamber 12 Toner supply chamber 13 Developing roller 14 Control member 15 Supply roller 16 Toner stirring member 17 Opening portion

JP 2008-33308 A JP 2007-286236 A Japanese Patent No. 2703922

Claims (6)

In the developing roller having a base layer made of an elastic body provided on the surface of the conductive core metal and a surface layer provided on the base layer, at least in a two-layer structure,
The complex impedance plot when an alternating voltage is applied at different frequencies has two peaks, the first peak width is 10 ⁷ Ω to 10 ⁸ Ω, and the first peak height is 10 ⁶ Ω to 10 A developing roller, characterized in that it is ⁸ Ω or less, the second peak width is from 10 ⁴ Ω to 10 ⁷ Ω, and the second peak height is from 10 ³ Ω to 10 ⁷ Ω. The developing roller according to claim 1.
A developing roller, wherein Zs> Zb and 5000> Zs / Zb> 50 are satisfied, where Zs is the first peak width and Zb is the second peak width. The developing roller according to claim 1 or 2,
A developing roller, wherein the material constituting the base layer includes at least one of urethane rubber, chloropyrene rubber, butadiene acrylonitrile, and epichlorohydrin rubber, and has a JIS-A hardness of 40 ° to 50 °. In a developing device having a developing roller disposed opposite to an electrostatic latent image holding member that holds an electrostatic latent image, and a regulating member that regulates a layer thickness of toner supplied onto the developing roller,
A developing device using the developing roller according to claim 1, 2 or 3 as the developing roller. From a latent image carrier that carries a latent image, a charging unit that uniformly charges the latent image carrier, a developing unit that develops the latent image on the latent image carrier, and a cleaning unit that cleans the latent image carrier In a process cartridge that integrally supports at least one selected means and is detachable from the image forming apparatus main body,
A process cartridge using the developing device according to claim 4 as the developing means. An image forming apparatus comprising: an image carrier; a developing unit that develops an electrostatic latent image formed on the image carrier; and a transfer unit that transfers a toner image formed on the image carrier to a transfer body In
An image forming apparatus using the developing device according to claim 4 as the developing means.

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