JP2012008439A - Full color image forming method and full color image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a full color image forming method and a full color image forming device, by which the occurrence of color unevenness and color muddiness is suppressed, a color reproduction range in a red to orange area is extended, and an image with excellent light resistance is obtained.SOLUTION: The full color image forming method is provided to form a full color image using at least six color toners for electrostatic charge image development each containing a binder resin and a colorant. The six color toners for electrostatic charge image development are a yellow toner, a magenta toner, a cyan toner, an orange toner, a green toner and a black toner, and the colorant contained in the orange toner comprises a specific polycyclic quinone pigment.

Description

  The present invention relates to a full-color image forming method and a full-color image forming apparatus.

  In an electrophotographic image forming method using an electrostatic charge image developing toner (hereinafter, also simply referred to as “toner”), in recent years, in addition to a conventional monochrome image, an opportunity to form a full-color image is increasing. . The electrophotographic full color image forming method is widely used in the field of light printing because it does not require a printing plate and can produce the required number of printed materials on demand.

  In particular, when full-color images such as catalogs and advertisements are formed, it is required to reproduce the original hue more faithfully. When a person or the like is included in such a full color image, the color reproducibility of the person's skin color greatly affects the impression of the entire image.

  In general, in an electrophotographic full color image forming method, color reproduction is performed by combining three color toners of yellow toner, magenta toner, and cyan toner. For example, when reproducing skin color, a toner image of yellow toner is used. And the magenta toner image are overlapped, there is a problem that it is difficult to reproduce a desired skin color due to a decrease in saturation and brightness.

  In recent years, there has been an increasing opportunity to create an image by computer graphics on a display and output the image. However, the color reproduction range of a full-color image that can be formed by a full-color image forming method using an electrophotographic method is much narrower than the color reproduction range of a full-color image that can be displayed on a display. There is a problem that it is difficult to reproduce a full color image on a transfer material such as paper with the same hue.

  As one of the technologies for expanding the color reproduction range, for example, in addition to four color toners composed of yellow toner, magenta toner, cyan toner and black toner, toners of six or more colors such as orange toner and green toner are used. The full color image forming method used is known. That is, the hue represented by 360 ° in the Munsell hue circle is not reproduced by using three color toners composed of yellow toner, magenta toner, and cyan toner, but orange toner and green toner are added thereto. By performing color reproduction using color toner, the color reproduction range is expanded.

  However, even with such a full-color image forming method, color reproducibility in a red to orange region such as a flesh color cannot be sufficiently obtained. In order to solve such a problem, it is disclosed that the color reproduction range of the red to orange region is expanded by an orange toner using a combination of a magenta colorant and an orange colorant (see, for example, Patent Document 1). In addition, C.I. I. It is disclosed that the color reproduction range of the red to orange region is expanded by an orange toner using an orange colorant such as CI Pigment Orange 11 (see, for example, Patent Documents 2 and 3).

  However, many of the orange colorants contained in such orange toners have low dispersibility in the binder resin constituting the orange toner, and the orange colorant fine particles aggregate and disperse unevenly. And color turbidity occurred, and the color reproduction range of the red to orange region could not be sufficiently expanded. Furthermore, the obtained image did not have excellent light resistance.

JP 2008-3274 A JP 2007-304401 A Japanese Patent Application Laid-Open No. 2002-156776

  The present invention has been made based on the above circumstances, and its purpose is to suppress the occurrence of color unevenness and color turbidity, to expand the color reproduction range of red to orange regions, and to provide excellent light resistance. It is an object of the present invention to provide a full-color image forming method and a full-color image forming apparatus capable of obtaining an image having a property.

1. A method for forming a full-color image using at least six colors of electrostatic charge image developing toners each containing a binder resin and a colorant,
The six color electrostatic image developing toners are yellow toner, magenta toner, cyan toner, orange toner, green toner and black toner,
A full-color image forming method, wherein the colorant contained in the orange toner is at least one selected from polycyclic quinone pigments represented by the following general formula (1), (2) or (3).

(In the general formulas (1), (2) and (3), X represents a chlorine atom, a bromine atom or an iodine atom, n represents an integer of 0 to 4, and m represents an integer of 0 to 6.)
2. The colorant contained in the orange toner is C.I. I. Pigment red 168, C.I. I. Pigment orange 19, C.I. I. 2. The full-color image forming method as described in 1 above, wherein the full-color image forming method is any one of Bat Red 37.
3. The colorant contained in the orange toner is C.I. I. 3. The full-color image forming method as described in 1 or 2 above, which is CI Pigment Red 168.
4). The orange toner is prepared by mixing a dispersion liquid in which fine particles of a colorant are dispersed in an aqueous medium and a dispersion liquid in which fine particles of a binder resin are dispersed in an aqueous medium to obtain the fine particles of the colorant and the binder. 4. The full-color image forming method as described in any one of 1 to 3 above, which is obtained by a process of aggregating and fusing fine particles of a resin.
5). A full-color image forming apparatus having at least six-color image forming means and an intermediate transfer member, wherein the six-color image forming means includes a yellow toner image, an orange toner image, a magenta toner image, a cyan toner image, and a green toner image. And a black toner image, and the intermediate transfer member sequentially superimposes and transfers the toner images formed by the six-color image forming means to form a full-color toner image. A toner image is collectively transferred onto a transfer material, and the image forming means for forming the orange toner image uses the orange toner used in the full color image forming method described in any one of 1 to 4 above. A full-color image forming apparatus.

  In the full-color image forming method of the present invention, the orange toner includes a dispersion liquid in which fine particles of a colorant are dispersed in an aqueous medium, and a dispersion liquid in which fine particles of a binder resin are dispersed in an aqueous medium. It is preferably obtained by mixing and then aggregating and fusing the fine particles of the colorant and the fine particles of the binder resin.

  The full-color image forming apparatus of the present invention is characterized in that the above-described full-color image forming method is executed.

  According to the full-color image forming method of the present invention, since the colorant contained in the orange toner used in the full-color toner image forming method is made of a specific polycyclic quinone pigment, occurrence of color unevenness and color turbidity is suppressed. As a result, the color reproduction range of the red to orange region is expanded and an image having excellent light resistance is obtained.

  The reason why such an effect can be obtained is that the polycyclic quinone pigment constituting the colorant contained in the orange toner is excellent in dispersibility, so that the polycyclic quinone pigment is used in the toner particles and on the fixed image. It is assumed that the fine particles are uniformly dispersed. Moreover, since the molecule | numerator which comprises a polycyclic quinone pigment is a thing of the structure stable with respect to light, it is thought that the light resistance of the image obtained improves.

  According to the full color image forming apparatus of the present invention, the occurrence of color unevenness and color turbidity is suppressed by executing the full color image forming method of the present invention, and the color reproduction range of the red to orange region is expanded. An image having excellent light resistance can be formed. In other words, the pigment is uniformly dispersed as fine particles having a small particle diameter in the toner particles or on the fixed image, and thus the clear hue inherent in the pigment is reproduced with little color unevenness, color turbidity, and a decrease in brightness. . This is because, in general, when the particle diameter of the pigment is small, the absorption wavelength region becomes sharp and there is no color turbidity, and particularly when the secondary color is used, the color turbidity hardly occurs.

  In addition, the reason why the dispersibility of the polycyclic quinone pigment of the present invention is good is that the quinone portion has an affinity for water and polar groups, so that it has good wettability with polyester and acrylic resin and further with water. The dispersibility is considered to be good for them. Therefore, it is considered that good color reproducibility can be obtained even when used in a chemical production method that is dispersed in water during the toner production method, such as an emulsion aggregation toner.

  In addition, the polycyclic quinone pigment of the present invention is excellent in light resistance. This is because the polycyclic quinone molecules have a planar structure, and primary particles are formed in a state where each molecule is stacked. And stabilizing against light. This is presumably because they are protected from each other by being in a stacking state, and are not easily attacked by triplet oxygen generated by light or ultraviolet rays.

FIG. 6 is a conceptual diagram showing expansion of a color reproduction range when using six colors of toner of the present invention. 1 is a cross-sectional view for explaining an example of a configuration of a full-color image forming apparatus in which a full-color image forming method of the present invention is executed.

  Hereinafter, the present invention will be described in detail.

<Full color image forming method>
In the full color image forming method of the present invention, at least six colors of yellow toner, magenta toner, cyan toner, green toner, black toner, and orange toner containing a colorant comprising a polycyclic quinone pigment are used. It can be executed by mounting in an image forming apparatus.

  The full-color image forming method of the present invention may use toners of other colors other than the above six toners, and examples of other color toners include blue toner and gray toner.

(Color reproducibility range)
Here, the “color reproducibility range” by the multicolor image forming method will be described below. FIG. 1 is a conceptual diagram showing a color reproduction range of a full color image forming method using six color toners of the present invention.

  The color reproduction range of electrophotography is determined by the three primary colors Y (yellow), M (magenta), and C (cyan) of the subtractive color mixing method, and the secondary colors R (red), G (green), and B ( Blue) is represented by secondary colors of Y and M, C and Y, and M and C, respectively, so that RGB is reproduced beyond the original YMC color reproduction range (shown by the solid line in FIG. 1). Is impossible in principle. Therefore, if orange and green toners with higher saturation are added, the occurrence of color unevenness and color turbidity is suppressed, and the color reproduction range is expanded (indicated by the broken line in FIG. 1), particularly leading to the reproduction of skin color. The color reproduction range of the red to orange region can be expanded.

The full-color image forming apparatus in which the full-color image forming method of the present invention is executed may be any apparatus that can form a color image on a transfer material by having at least the following means.
(A) Electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier (b) The electrostatic latent image formed on the electrostatic latent image carrier is carried on the developer carrier. Developing means for developing a toner image by developing with the developer (c) Transfer means for transferring the toner image onto the transfer material (d) Fixing means for thermally fixing the toner image transferred onto the transfer material Full color of the present invention Specific examples of the image forming method include the following methods (1) and (2).
(1) a toner image forming step of directly transferring a toner image formed by developing the electrostatic latent image formed on the electrostatic latent image carrier with a toner onto a transfer material, at least yellow toner; Each of the toner image forming steps is performed using six toners of orange toner, green toner, cyan toner, magenta toner, and black toner, thereby obtaining a transfer material carrying a plurality of toner images having different colors. A so-called direct transfer type full color image forming method in which a full color image is formed by fixing an image on a transfer material.
(2) a toner image forming step of transferring a toner image formed by developing the electrostatic latent image formed on the electrostatic latent image carrier with toner to an intermediate transfer member, and at least yellow toner; By performing the toner image forming process using each of the six toners of orange toner, green toner, cyan toner, magenta toner and black toner, an intermediate transfer member carrying a plurality of toner images having different colors is obtained. A so-called intermediate transfer type full-color image forming method in which a toner image is transferred onto a transfer material and fixed to form a full-color image.

  Hereinafter, an example of an intermediate transfer type full-color image forming method will be described in detail.

  FIG. 2 is a cross-sectional view for explaining an example of the configuration of a full-color image forming apparatus in which the full-color image forming method of the present invention is executed.

  This full-color image forming apparatus includes an endless belt-like intermediate transfer body (hereinafter referred to as “intermediate transfer belt”) 17 arranged in a stretched state by a plurality of support rollers 17a to 17d. Along the outer peripheral surface of the intermediate transfer belt 17, six toner image forming units for forming a yellow toner image, an orange toner image, a magenta toner image, a cyan toner image, a green toner image and a black toner image, respectively (present invention) 6Y image forming means) 30Y, 30Or, 30M, 30C, 30G, 30K are the photosensitive drums 10Y, 10Or, which are the electrostatic latent image carriers in the intermediate transfer belt 17 in each toner image forming unit. 10M, 10C, 10G, and 10K are arranged so as to be circulated while being in contact with each other and arranged in a spaced manner It has been.

  The toner image forming unit 30Y related to the yellow toner image is arranged so as to be arranged in order of operation with respect to the rotating direction of the photosensitive drum 10Y along the rotating photosensitive drum 10Y and the outer peripheral surface of the photosensitive drum 10Y. The charging unit 11Y, the exposure unit 12Y, the developing unit 13Y, the primary transfer unit 14Y, and the cleaning unit 20Y are provided.

  The primary transfer unit 14Y is pressed against the photosensitive drum 10Y via the intermediate transfer belt 17, and a primary transfer roller 141Y provided so as to form a primary transfer region (primary transfer nip portion), and the primary transfer roller 141Y. The transfer current supply means (not shown) is connected, and a transfer electric field is formed by supplying a predetermined transfer current to the primary transfer roller 141Y by the transfer current supply means. The yellow toner image formed on the photosensitive drum 10Y by the action of the electric field is primarily transferred onto the intermediate transfer belt 17.

  For each of the other toner image forming units 30Or, 30M, 30C, 30G, and 30K, the developer includes orange toner, magenta toner, cyan toner, green toner, and black toner instead of yellow toner. The configuration is the same as that of the toner image forming unit 30Y related to the toner image. In FIG. 2, for the sake of convenience, the same components as those of the toner image forming unit 30Y related to the yellow toner image are indicated by “Y”. The same reference numerals are used instead of “Or”, “M”, “C”, “G”, and “K”.

  A secondary transfer unit 14S is provided at a position downstream of the toner image forming unit arrangement region in the moving direction of the intermediate transfer belt 17 (indicated by an arrow in FIG. 2).

  The secondary transfer unit 14S is pressed by the backup roller 17d, which is one of the support rollers that support the intermediate transfer belt 17, via the intermediate transfer belt 17, so that a secondary transfer region (secondary transfer nip portion) is formed. The secondary transfer roller 141S is provided, and a transfer voltage application unit (not shown) connected to the secondary transfer roller 141S. The potential of the primary transfer toner image is formed by the transfer voltage application unit. A transfer electric field is formed by applying a secondary transfer bias voltage of the opposite polarity to the secondary transfer roller 141S, and the primary transfer toner image formed on the intermediate transfer belt 17 by the action of the transfer electric field is transferred to the transfer material P. Transcribed above.

  In FIG. 2, 18 is a fixing device for fixing the toner image on the transfer material P conveyed from the secondary transfer region. For example, a heating roller 181 having a heating source therein, and the heating roller 181 and the fixing device are fixed. The pressure roller 182 is provided in a pressure contact state so that a nip portion is formed.

  Reference numeral 20S denotes an intermediate transfer member cleaning means provided with a cleaning blade for removing untransferred toner on the intermediate transfer belt 17, and is provided at a position downstream of the secondary transfer region in the moving direction of the intermediate transfer belt 17. ing.

  In such a full-color image forming apparatus, first, for each color formed on the photosensitive drums 10Y, 10Or, 10M, 10C, 10G, and 10K of the toner image forming units 30Y, 30Or, 30M, 30C, 30G, and 30K. The toner images are sequentially transferred and superimposed on the intermediate transfer belt 17, and the toner image primarily transferred onto the intermediate transfer belt 17 is secondarily transferred onto the transfer material P by the secondary transfer means 14S and fixed. A toner image is formed on the transfer material P by heating and pressing in the apparatus 18.

〔toner〕
The toners of at least six colors used in the full color image forming method of the present invention each contain at least a binder resin and a colorant.

  Further, each color toner used in the full-color image forming method of the present invention may contain internal additives such as magnetic powder, a charge control agent and a release agent, if necessary.

(Particle diameter of toner particles)
The particle diameter of the toner particles of each color is preferably 4 to 10 μm, and more preferably 5 to 9 μm, for example, in terms of volume-based median diameter.

  When the volume-based median diameter is in the above range, the transfer efficiency is increased, the image quality of halftone is improved, and the image quality of fine lines and dots is improved.

  The volume-based median diameter of the toner particles is measured and calculated using a measuring apparatus in which a computer system for data processing (manufactured by Beckman Coulter) is connected to “Coulter Multisizer 3” (manufactured by Beckman Coulter). .

  Specifically, 0.02 g of toner is added to 20 ml of a surfactant solution (for example, a surfactant solution obtained by diluting a neutral detergent containing a surfactant component 10 times with pure water for the purpose of dispersing toner particles). Then, ultrasonic dispersion treatment was performed for 1 minute to prepare a toner particle dispersion, and this toner particle dispersion was placed in “ISOTON II” (Beckman Coulter, Inc.) in the sample stand. Pipette into beaker until display concentration of measuring device is 5-10%. Here, a reproducible measurement value can be obtained by setting the concentration range. In the measuring apparatus, the measurement particle count is 25000, the aperture diameter is 100 μm, the frequency range is calculated by dividing the measurement range of 1 to 30 μm into 256, and the volume integrated fraction is 50 % Particle diameter is the volume-based median diameter.

(Temperant softening point temperature)
The toner of each color used in the full color image forming method of the present invention preferably has a softening point temperature (Tsp) of 70 ° C. or higher and 110 ° C. or lower, and more preferably 70 ° C. or higher and 100 ° C. or lower. The colorant constituting the toner of each color used in the present invention has a stable property that the spectrum does not change even under the influence of heat, but the softening point temperature (Tsp) is in the above range. As a result, the influence of heat applied to the toner during fixing can be further reduced. Therefore, since image formation can be performed without imposing a burden on the colorant, it is expected that a wider and more stable color reproducibility is expressed.

  In addition, since the toner softening point temperature (Tsp) is in the above range, toner image fixing can be performed at a temperature lower than that of the prior art, and environmentally friendly image formation with reduced power consumption can be realized. Can do.

The softening point temperature (Tsp) of the toner can be controlled by, for example, the following methods alone or in combination. That is,
(1) The type and composition ratio of the monomer that should form the binder resin are adjusted.
(2) The molecular weight of the binder resin is adjusted by the type and amount of chain transfer agent.
(3) Adjust the type and amount of release agent.

As a method for measuring the softening point temperature (Tsp) of the toner, for example, “Flow Tester CFT-500 (manufactured by Shimadzu Corporation)” is used to form a cylindrical shape having a height of 10 mm and heated at a temperature rising rate of 6 ° C./min. While applying a pressure of 1.96 × 10 ⁶ Pa from the plunger and pushing it out from a nozzle with a diameter of 1 mm and a length of 1 mm, the curve between the plunger drop amount and temperature of the flow tester (softening flow curve) There is a method of drawing, in which the first flowing temperature is the melting start temperature, and the temperature for the drop amount of 5 mm is the softening point temperature.

(Coloring agent)
As the colorant contained in the orange toner used in the full color image forming method of the present invention, a polycyclic quinone type pigment represented by the following general formula (1), (2) or (3) is used. You may use individually or in combination of 2 or more types. Of these, C.I. I. Pigment red 168, C.I. I. Pigment orange 19, C.I. I. It is preferable to use the bat red 37.

(In the general formulas (1), (2) and (3), X represents a chlorine atom, a bromine atom or an iodine atom, n represents an integer of 0 to 4, and m represents an integer of 0 to 6.)
The polycyclic quinone pigment of the present invention represented by the general formulas (1), (2) and (3) can be easily synthesized by a known method.

(Exemplary compounds)
Examples of the polycyclic quinone pigment used in the orange toner of the present invention include the following pigments, but the orange pigment effective for the orange toner of the present invention is not limited thereto.

  The content of the colorant of the present invention contained in the orange toner is preferably 2 to 12 parts by mass, more preferably 3 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  When the content of the colorant of the present invention contained in the orange toner is within the above range, vivid red to orange color reproduction without color turbidity becomes possible.

  The colorant of the present invention contained in the orange toner is preferably dispersed in the orange toner in a number average primary particle size of about 50 to 500 nm.

  The number average primary particle diameter is 10 times the size of the ferret direction of the colorant fine particles in the orange toner particles using a photograph in which the cross section of the orange toner particles is enlarged 50,000 times with a transmission electron microscope. It is obtained by measuring and calculating the arithmetic average value.

  The colorant contained in the orange toner may contain a known orange color material other than the polycyclic quinone pigment. In this case, the content of the orange material is preferably less than 40 parts by mass with respect to 100 parts by mass of the polycyclic quinone pigment that is the colorant of the present invention.

  As the colorant contained in the toner other than the orange toner used in the full-color image forming method of the present invention, a conventionally known colorant can be used.

  Examples of the colorant contained in the yellow toner include C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Pigment yellow 14, 17, 74, 93, 94, 138, 155, 180, 185, and the like. These can be used alone or in combination of two or more. Among these, C.I. I. Pigment Yellow 74 is preferable.

  The content of the colorant contained in the yellow toner is preferably 1 to 15 parts by mass, more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  Examples of the colorant contained in the magenta toner include C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 122, C.I. I. Pigment Red 5, 48: 1, 53: 1, 57: 1, 122, 139, 144, 149, 166, 177, 178, 222, and the like. These can be used alone or in combination of two or more. Among these, C.I. I. Pigment Red 122 is preferable.

  The content of the colorant contained in the magenta toner is preferably 1 to 15 parts by mass, more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  Examples of the colorant contained in the cyan toner include C.I. I. Pigment blue 15: 3.

  The content of the colorant contained in the cyan toner is preferably 1 to 15 parts by mass, more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  Examples of the colorant contained in the green toner include C.I. I. And CI Pigment Green 7.

  The content of the colorant contained in the green toner is preferably 1 to 15 parts by mass, more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  Examples of the colorant contained in the black toner include carbon black, magnetic material, and titanium black. Examples of carbon black include channel black, furnace black, acetylene black, thermal black, and lamp black. Examples of magnetic materials include ferromagnetic metals such as iron, nickel, and cobalt, alloys containing these ferromagnetic metals, compounds of ferromagnetic metals such as ferrite and magnetite, and ferromagnetic materials that do not contain ferromagnetic metals but are heat treated. The alloy shown etc. are mentioned. Examples of alloys that exhibit ferromagnetism by heat treatment include Heusler alloys such as manganese-copper-aluminum and manganese-copper-tin, and chromium dioxide.

  The content of the colorant contained in the black toner is preferably 1 to 15 parts by mass, more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  The colorants contained in the yellow toner, magenta toner, cyan toner, green toner and black toner are each preferably dispersed in the toner in a number average primary particle size of about 50 to 500 nm.

(Binder resin)
The binder resin contained in each color toner used in the full color image forming method of the present invention is not particularly limited, and a known resin can be used.

  When each color toner is manufactured by a pulverization method, for example, a styrene resin, a (meth) acrylic resin, a styrene- (meth) acrylic copolymer resin, a vinyl resin such as an olefin resin, a polyester Resins, polyamide resins, polycarbonate resins, polyether resins, polyvinyl acetate resins, polysulfone resins, epoxy resins, polyurethane resins, urea resins, and the like can be used. These may be used alone or in combination of two or more.

  In addition, when each color toner is manufactured by suspension polymerization method, emulsion aggregation method or the like, various known polymerizable monomers can be used as the polymerizable monomer for obtaining the binder resin constituting the toner particles. As the polymerizable monomer, for example, a vinyl monomer is used, and it is preferable to use a combination of those having an ionic dissociation group. Moreover, by using a polyfunctional vinyl monomer as the polymerizable monomer, a binder resin having a crosslinked structure can be obtained.

(Charge control agent)
The charge control agent is not particularly limited as long as it is a substance that can give positive or negative charge by frictional charging and is colorless, and various known positive charge control agents and negative charge control agents are used. be able to.

  The content of the charge control agent is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

(Release agent)
Various known waxes can be used as the release agent.

  Examples of the wax include polyolefin waxes such as polyethylene wax and polypropylene wax, branched hydrocarbon waxes such as microcrystalline wax, long chain hydrocarbon waxes such as paraffin wax and sazol wax, and dialkyls such as distearyl ketone. Ketone wax, carnauba wax, montan wax, behenate behenate, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18-octadecanedioldi Ester waxes such as stearate, tristearyl trimellitic acid, distearyl maleate, ethylenediamine behenylamide, tristearyl trimellitic acid Such as amide-based waxes such as bromide and the like.

  It is preferable that content of a mold release agent is 0.1-30 mass parts with respect to 100 mass parts of binder resin, More preferably, it is 1-20 mass parts.

(External additive)
As the toner of each color used in the full-color image forming method of the present invention, the toner particles can be used as they are, but in order to improve the fluidity, chargeability, cleaning properties, etc. with respect to the toner particles, External additives such as a fluidizing agent and a cleaning aid may be added and used.

  Examples of the external additive include inorganic oxide fine particles such as silica fine particles, alumina fine particles, and titanium oxide fine particles, inorganic stearate compound fine particles such as aluminum stearate fine particles and zinc stearate fine particles, strontium titanate, and zinc titanate. Inorganic fine particles such as inorganic titanic acid compound fine particles.

  These inorganic fine particles are preferably those subjected to surface treatment with a silane coupling agent, a titanium coupling agent, a higher fatty acid, silicone oil, or the like from the viewpoint of heat-resistant storage stability and environmental stability.

  The addition amount of the external additive is 0.05 to 5 parts by mass, preferably 0.1 to 3 parts by mass with respect to 100 parts by mass of the toner. Various external additives may be used in combination.

(Toner production method)
The toner of each color used in the full-color image forming method of the present invention obtains toner particles using a binder resin, a colorant, and an internal additive as necessary, and externally removes toner particles as necessary. It can manufacture by adding an additive.

  Examples of the method for producing each color toner include a pulverization method, a suspension polymerization method, and other known methods, but it is preferable to use an emulsion aggregation method. According to this emulsion aggregation method, the toner particles can be easily reduced in size from the viewpoint of production cost and production stability.

  Here, the emulsion aggregation method refers to a dispersion of fine particles of a binder resin produced by an emulsion polymerization method (hereinafter also referred to as “binder resin fine particles”). And agglomerated until the toner particle diameter is a desired value, and further, the shape is controlled by fusing the binder resin fine particles to produce toner particles. . Here, the fine particles of the binder resin may optionally contain a release agent, a charge control agent, and the like.

An example of using the emulsion aggregation method as a method for producing the toner is shown below.
(1) Step of preparing a dispersion liquid in which colorant fine particles are dispersed in an aqueous medium (2) Dispersion liquid in which binder resin fine particles containing an internal additive are dispersed in an aqueous medium as necessary (3) A step of mixing the colorant fine particle dispersion and the binder resin fine particle dispersion to form toner particles by aggregating, associating and fusing the colorant fine particles and the binder resin fine particles. (4) Step of filtering toner particles from a dispersion system (aqueous medium) of toner particles and removing the surfactant, etc. (5) Step of drying the toner particles (6) Step of adding an external additive to the toner particles In the case of producing a toner by the emulsion aggregation method, the binder resin fine particles obtained by the emulsion polymerization method may have a multilayer structure of two or more layers made of binder resins having different compositions. The binder resin fine particles For example, for a resin having a two-layer structure, a dispersion of resin particles is prepared by emulsion polymerization treatment (first-stage polymerization) according to a conventional method, and a polymerization initiator and a polymerizable monomer are added to the dispersion. , And can be obtained by a technique of polymerizing this system (second stage polymerization).

  In addition, toner particles having a core-shell structure can be obtained by an emulsion aggregation method. Specifically, toner particles having a core-shell structure are obtained by first combining binder resin fine particles and colorant fine particles for core particles. Aggregating, associating and fusing to produce core particles, and then adding binder resin fine particles for the shell layer to the core particle dispersion to agglomerate the binder resin fine particles for the shell layer on the surface of the core particles. It can be obtained by forming a shell layer that covers the surface of the core particles by fusing.

  In particular, the orange toner used in the full color image forming method of the present invention is a mixture of a dispersion liquid in which fine colorant particles are dispersed in an aqueous medium and a dispersion liquid in which binder resin fine particles are dispersed in an aqueous medium. Thus, it is preferable that the colorant fine particles and the binder resin fine particles are obtained by a process of aggregating and fusing, that is, obtained by a production method such as an emulsion aggregation method. The reason why such a production method is preferable is that since a highly dispersible polycyclic quinone pigment is used as the colorant contained in the orange toner, the dispersibility of the colorant fine particles in the dispersion is excellent. This is because the toner particles can be formed while maintaining the excellent dispersibility of the colorant fine particles even when the binder resin fine particles are aggregated and fused.

  The particle diameter of the orange colorant fine particles in the step (1) is preferably 100 to 300 nm as a volume-based median diameter.

An example of using a pulverization method as a toner production method is shown below.
(1) Step of mixing binder resin, colorant and, if necessary, internal additive with Henschel mixer etc. (2) Step of kneading the resulting mixture while heating with an extrusion kneader etc. (3) obtained After coarsely grinding the kneaded product with a hammer mill or the like, and further crushing with a turbo mill or the like (4), the obtained pulverized product is finely classified using, for example, an airflow classifier utilizing the Coanda effect. Step of forming toner particles (5) Step of adding external additive to toner particles (Developer)
Each color toner used in the full-color image forming method of the present invention can be used as a non-magnetic one-component developer, but may be mixed with a carrier and used as a two-component developer. The black toner can also be used as a magnetic one-component developer.

  When used as a two-component developer, the carrier is made of a conventionally known material such as a ferromagnetic metal such as iron, an alloy such as ferromagnetic metal and aluminum and lead, and a compound of ferromagnetic metal such as ferrite and magnetite. Magnetic particles can be used, and ferrite particles are particularly preferable. As the carrier, a coated carrier in which the surface of magnetic particles is coated with a coating agent such as a resin, a binder type carrier in which magnetic fine powder is dispersed in a binder resin, and the like can also be used. The coating resin constituting the coat carrier is not particularly limited, and examples thereof include olefin resins, styrene resins, styrene-acrylic resins, silicone resins, ester resins, and fluorine resins. Moreover, it does not specifically limit as resin which comprises a resin dispersion type carrier, A well-known thing can be used, For example, a styrene-acrylic-type resin, a polyester resin, a fluororesin, a phenol resin etc. can be used.

  The volume-based median diameter of the carrier is preferably 20 to 100 μm, and more preferably 20 to 60 μm.

  The volume-based median diameter of the carrier can be typically measured by a laser diffraction particle size distribution measuring apparatus “HELOS” (manufactured by SYMPATEC) equipped with a wet disperser.

(Transfer material)
Examples of the transfer material used in the full color image forming method of the present invention include plain paper from thin paper to thick paper, high-quality paper, coated printing paper such as art paper or coated paper, commercially available Japanese paper or postcard paper, OHP Various types of plastic film, cloth, etc. can be mentioned, but are not limited thereto.

  The embodiment of the full color image forming method of the present invention has been described above, but the present invention is not limited to the above embodiment, and various modifications can be added.

  According to the present invention, since the colorant contained in the orange toner used in the full-color toner image forming method is composed of a polycyclic quinone pigment, the occurrence of color unevenness and color turbidity is suppressed, and the red to orange color region is reduced. An image having excellent light resistance can be obtained while the color reproduction range is expanded.

  Specific examples of the present invention will be described below, but the present invention is not limited to these examples.

[Orange toner production example 1 (emulsion aggregation method)]
(1) Preparation Step of Colorant Fine Particle Dispersion [1] 11.5 parts by mass of sodium n-dodecyl sulfate was added to 160 parts by mass of ion-exchanged water, and dissolved and stirred to prepare an aqueous surfactant solution. In this surfactant aqueous solution, 15 parts by mass of a colorant (Exemplary Compound 1) is gradually added, and dispersion treatment is performed using “Clearmix W Motion CLM-0.8” (manufactured by M Technique Co., Ltd.). A colorant fine particle dispersion [1] was prepared.

  The colorant fine particles in the colorant fine particle dispersion [1] had a volume-based median diameter of 220 nm. The volume-based median diameter was measured under the following measurement conditions using “MICROTRAC UPA-150” (manufactured by HONEYWELL).

Sample refractive index: 1.59
Sample specific gravity: 1.05 (in terms of spherical particles)
Solvent refractive index: 1.33
Solvent viscosity: 0.797 (30 ° C), 1.002 (20 ° C)
Zero adjustment: Ion exchange water was added to the measurement cell for adjustment.

(2) Production Step of Core Part Resin Particles [1] Core part resin particles [1] having a multilayer structure were produced through the first stage polymerization, second stage polymerization, and third stage polymerization shown below.

(A) First-stage polymerization Interface obtained by dissolving 4 parts by mass of sodium polyoxyethylene-2-dodecyl ether sulfate in 3040 parts by mass of ion-exchanged water in a reaction vessel equipped with a stirrer, temperature sensor, cooling pipe, and nitrogen introducing apparatus The activator solution was charged, and the internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream.

  A polymerization initiator solution in which 10 parts by mass of potassium persulfate is dissolved in 400 parts by mass of ion-exchanged water is added to the surfactant aqueous solution, and the temperature is raised to 75 ° C. The body mixture was dropped into the reaction vessel over 1 hour.

Styrene 532 parts by mass n-butyl acrylate 200 parts by mass Methacrylic acid 68 parts by mass n-octyl mercaptan 16.4 parts by mass After the above monomer mixture is added dropwise, the system is heated and stirred at 75 ° C. for 2 hours. (Step 1 polymerization) was performed to prepare resin particles [A1]. The weight average molecular weight of the resin particles [A1] was 16,500.

(B) Second stage polymerization Into a flask equipped with a stirrer, a monomer mixed solution composed of the following compounds was charged, and paraffin wax “HNP-57” (manufactured by Nippon Seiwa Co., Ltd.) 93.8 mass as a release agent Part was added and heated to 90 to dissolve.

Styrene 101.1 parts by weight n-butyl acrylate 62.2 parts by weight Methacrylic acid 12.3 parts by weight n-octyl mercaptan 1.75 parts by weight On the other hand, 3 parts by weight of polyoxyethylene-2-dodecyl ether sodium sulfate was ion-exchanged water. A surfactant aqueous solution dissolved in 1560 parts by mass was prepared and heated to 98 ° C. A mechanical system having a circulation path after adding 32.8 parts by mass (in terms of solid content) of resin particles [A1] to the surfactant aqueous solution and further adding the monomer mixture containing the paraffin wax. It was mixed and dispersed for 8 hours with a disperser “CLEAMIX” (manufactured by M Technique). An emulsified particle dispersion containing emulsified particles having a dispersed particle size of 340 nm was prepared by mixing and dispersing.

  Next, a polymerization initiator solution in which 6 parts by mass of potassium persulfate was dissolved in 200 parts by mass of ion-exchanged water was added to this emulsified particle dispersion, and this system was polymerized by heating and stirring at 98 ° C. for 12 hours. (Second stage polymerization) was performed to prepare resin particles [A2]. The weight average molecular weight of the resin particles [A2] was 23,000.

(C) Third-stage polymerization A polymerization initiator solution in which 5.45 parts by mass of potassium persulfate is dissolved in 220 parts by mass of ion-exchanged water is added to the resin particles [A2], A monomer mixture composed of the compound was added dropwise over 1 hour.

Styrene 293.8 parts by mass n-butyl acrylate 154.1 parts by mass n-octyl mercaptan 7.08 parts by mass After completion of the dropwise addition, the mixture was heated and stirred for 2 hours to perform polymerization (third stage polymerization). The core part resin particle [1] was produced by cooling to 28 ° C. The weight average molecular weight of the core part resin particles [1] was 26,800.

(3) Production Step of Resin Particles [1] for Shell Similarly, except that the monomer mixture used in the first stage polymerization in the production of resin particles for core part [1] was changed to the following: Polymerization reaction and post-reaction treatment were performed to produce shell resin particles [1].

Styrene 624 parts by weight 2-ethylhexyl acrylate 120 parts by weight Methacrylic acid 56 parts by weight n-octyl mercaptan 16.4 parts by weight (4) Preparation process of orange toner [1] (a) Formation of core part Stirrer, temperature sensor, cooling In a reaction vessel equipped with a tube and a nitrogen introducing device,
Resin particles for core [1] 420.7 parts by mass (solid content conversion)
900 parts by mass of ion exchanged water Colorant fine particle dispersion [1] 300 parts by mass was charged and stirred. After adjusting the temperature in the reaction vessel to 30 ° C., a 5 mol / liter aqueous sodium hydroxide solution was added to adjust the pH to 8-11.

  Next, an aqueous solution obtained by dissolving 2 parts by mass of magnesium chloride hexahydrate in 1000 parts by mass of ion-exchanged water was added at 30 ° C. over 10 minutes with stirring. After standing for 3 minutes, the heating was started, and the system was heated to 65 ° C. over 60 minutes to associate the particles. In this state, the particle size of the associated particles was measured using “Multisizer 3” (manufactured by Coulter), and when the volume-based median diameter of the associated particles reached 5.8 μm, 40.2 parts by mass of sodium chloride was ion-exchanged. The association was stopped by adding an aqueous solution dissolved in 1000 parts by mass of water.

  After the association was stopped, the core temperature [1] was produced by continuing the fusion by heating and stirring for 1 hour at a liquid temperature of 70 ° C. as an aging treatment.

  When the average circularity of the core [1] was measured by “FPIA2100” (manufactured by Sysmec), it was 0.912.

(B) Formation of shell Next, the temperature of the above liquid is set to 65 ° C., and 50 parts by mass of resin particles for shell [1] (in terms of solid content) are added. Further, 2 parts by mass of magnesium chloride hexahydrate is ion-exchanged. An aqueous solution dissolved in 1000 parts by mass of water was added over 10 minutes, and then the temperature was raised to 70 ° C. and stirring was performed for 1 hour. In this manner, the shell resin particles [1] were fused to the surface of the core [1], and then aged at 75 ° C. for 20 minutes to form a shell.

  Thereafter, an aqueous solution in which 40.2 parts by mass of sodium chloride was dissolved in 1000 parts by mass of ion-exchanged water was added to stop shell formation. Further, the particles produced by cooling to 30 ° C. at a rate of 8 ° C./min are filtered, washed repeatedly with ion exchange water at 45 ° C., and then dried with hot air at 40 ° C. An orange toner particle [1] having

(C) External additive addition step The following external additives are added to the orange toner particles [1], and external addition processing is performed by “Henschel mixer” (manufactured by Mitsui Miike Mining Co., Ltd.) to produce orange toner [1]. did. The dispersion diameter of the colorant contained in the orange toner [1] was 310 nm as the number average primary particle diameter. The dispersion diameter is measured by the method described above. The orange toner [1] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

Silica fine particles treated with hexamethylsilazane 0.6 parts by mass Titanium dioxide fine particles treated with n-octylsilane 0.8 parts by mass External addition with a Henschel mixer was performed at a peripheral speed of a stirring blade of 35 m / second, a treatment temperature of 35 ° C, The treatment was carried out under conditions of 15 minutes.

[Orange toner production example 2]
Orange toner [2] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Exemplary Compound 4” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [2] was 350 nm as the number average primary particle diameter. The orange toner [2] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Preparation Example 3 of Orange Toner]
Orange toner [3] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Exemplary Compound 5” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [3] was 230 nm in number average primary particle diameter. The orange toner [3] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Orange toner production example 4]
Orange toner [4] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Exemplary Compound 6” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [4] was 250 nm in terms of number average primary particles. The orange toner [4] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Orange toner production example 5]
Orange toner [5] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Exemplary Compound 7” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [5] was 245 nm as the number average primary particle diameter. The orange toner [5] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Orange Toner Preparation Example 6]
Orange toner [6] was prepared in the same manner as in Preparation Example 2 of Orange Toner except that “Exemplary Compound 8” was used instead of “Exemplary Compound 4”. The dispersion diameter of the colorant contained in the orange toner [6] was 290 nm as the number average primary particle diameter. The orange toner [6] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Preparation Example 7 for Orange Toner]
Orange toner [7] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Exemplary Compound 12” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [7] was 300 nm in terms of number average primary particle diameter. The orange toner [7] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Preparation Example 8 for Orange Toner]
Orange toner [8] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Exemplary Compound 14” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [8] was 340 nm as the number average primary particle diameter. The orange toner [8] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Preparation Example 9 of Orange Toner]
Orange toner [9] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Exemplary Compound 17” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [9] was 370 nm as the number average primary particle diameter. The orange toner [9] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Orange Toner Preparation Example 10]
Orange toner [10] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Exemplary Compound 16” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [10] was 450 nm in terms of number average primary particle diameter. The orange toner [10] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Orange toner production example 11 (pulverization method)]
(1) Mixing step The following materials were mixed with a “Henschel mixer” (manufactured by Mitsui Mining Co., Ltd.) at a peripheral speed of a stirring blade of 25 m / sec. Over 5 minutes to obtain a mixture.

Polyester resin (Bisphenol A-ethylene oxide adduct, terephthalic acid, trimellitic acid condensate: weight average molecular weight 20,000) 100 parts by weight Colorant (Exemplary Compound 5) 6 parts by weight Release agent (pentaerythritol tetrastearate ) 6 parts by mass Charge control agent (boron dibenzylate) 1 part by mass (2) Kneading step The obtained mixture was kneaded while heating to 110 ° C. with a twin-screw extrusion kneader to obtain a kneaded product. Cooled down.

(3) Grinding step The obtained kneaded material was coarsely pulverized with a “hammer mill” (manufactured by Hosokawa Micron), and then finely pulverized with a “turbo mill T-400 type” (manufactured by Turbo Kogyo).

(4) Classifying step The obtained fine powder was finely classified by an air classifier to obtain orange toner particles [11] having a volume-based median diameter of 8.0 μm.

(5) External additive addition step The following external additives are added to the orange toner particles [11] and subjected to external addition processing by “Henschel mixer” (manufactured by Mitsui Miike Mining Co., Ltd.) to produce orange toner [11]. did. The dispersion diameter of the colorant contained in the orange toner [11] was 290 nm as the number average primary particle diameter. The dispersion diameter is measured by the method described above. The orange toner [11] had a softening point temperature (Tsp) of 110 ° C. and a toner particle diameter of 8.0 μm in terms of volume-based median diameter.

Silica fine particles treated with hexamethyldisilazane 0.6 parts by mass Fine titanium dioxide particles treated with n-octylsilane 0.8 parts by mass External addition with a Henschel mixer was performed at a peripheral speed of a stirring blade of 35 m / second and a treatment temperature of 35 ° C. , Under conditions of a processing time of 15 minutes.

[Orange Toner Preparation Example 12]
Orange toner [12] was prepared in the same manner as in Preparation Example 11 of Orange Toner except that “Exemplary Compound 6” was used instead of “Exemplary Compound 5”. The dispersion diameter of the colorant contained in the orange toner [12] was 300 nm in terms of number average primary particle diameter. The orange toner [12] had a softening point temperature (Tsp) of 110 ° C. and a toner particle diameter of 8.0 μm in terms of volume-based median diameter.

[Orange Toner Preparation Example 13]
Orange toner [13] was prepared in the same manner as in Preparation Example 11 of Orange Toner except that “Exemplary Compound 7” was used instead of “Exemplary Compound 5”. The dispersion diameter of the colorant contained in the orange toner [13] was 310 nm as the number average primary particle diameter. The orange toner [13] had a softening point temperature (Tsp) of 110 ° C. and a toner particle diameter of 8.0 μm in terms of volume-based median diameter.

[Orange Toner Preparation Example 14 (Toner of Comparative Example 1)]
Orange toner [14] was prepared in the same manner as in Preparation Example 1 of Orange Toner, except that “CI Pigment Orange 64” was used instead of “Exemplary Compound 1”. The dispersion diameter of the colorant contained in the orange toner [14] was 610 nm as the number average primary particle diameter. The orange toner [14] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Orange Toner Production Example 15 (Toner of Comparative Example 2)]
In orange toner production example 1, 7.5 parts by mass (15 parts by mass in total) of each of “CI Pigment Yellow 74 and CI Pigment Red 48: 1” were used instead of “Exemplary Compound 1”. An orange toner [15] was prepared in the same manner as above. The dispersion diameter of the colorant contained in the orange toner [15] was 610 nm as the number average primary particle diameter. The orange toner [15] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Preparation Example 1 of Yellow Toner]
Yellow toner [1] was prepared in the same manner as in Preparation Example 1 of Orange Toner, except that “CI Pigment Yellow 74” was used instead of “Exemplary Compound 1”. The yellow toner [1] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Production Example 2 of Yellow Toner]
A yellow toner [2] was prepared in the same manner as in Preparation Example 11 of Orange Toner except that “CI Pigment Yellow 74” was used instead of “Exemplary Compound 5”. The yellow toner [2] had a softening point temperature (Tsp) of 110 ° C. and a toner particle diameter of 8.0 μm in terms of volume-based median diameter.

[Magenta Toner Production Example 1]
Magenta toner [1] was prepared in the same manner as in Preparation Example 1 of Orange Toner, except that “CI Pigment Red 122” was used instead of “Exemplary Compound 1”. The magenta toner [1] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Magenta Toner Preparation Example 2]
Magenta toner [2] was prepared in the same manner as in Preparation Example 11 of Orange Toner, except that “CI Pigment Red 122” was used instead of “Exemplary Compound 5”. The magenta toner [2] had a softening point temperature (Tsp) of 110 ° C. and a toner particle diameter of 8.0 μm in terms of volume-based median diameter.

[Cyan toner production example 1]
Cyan toner [1] was prepared in the same manner as in Preparation Example 1 of Orange Toner, except that “CI Pigment Blue 15: 3” was used instead of “Exemplary Compound 1”. The cyan toner [1] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Cyan toner production example 2]
Cyan toner [2] was prepared in the same manner as in Preparation Example 11 of Orange Toner except that “CI Pigment Blue 15: 3” was used instead of “Exemplary Compound 5”. The cyan toner [2] had a softening point temperature (Tsp) of 110 ° C. and a toner particle diameter of 8.0 μm in terms of volume-based median diameter.

[Green toner production example 1]
Green toner [1] was prepared in the same manner as in Preparation Example 1 of Orange Toner, except that “CI Pigment Green 7” was used instead of “Exemplary Compound 1”. The green toner [1] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm as a volume-based median diameter.

[Green toner production example 2]
Green toner [2] was prepared in the same manner as in Preparation Example 11 of Orange Toner except that “CI Pigment Green 7” was used instead of “Exemplary Compound 5”. The green toner [2] had a softening point temperature (Tsp) of 110 ° C. and a toner particle diameter of 8.0 μm in terms of volume-based median diameter.

[Black toner production example 1]
Black toner [1] was prepared in the same manner as in Preparation Example 1 of Orange Toner except that “Carbon Black: Mogal L” was used instead of “Exemplary Compound 1”. The black toner [1] had a softening point temperature (Tsp) of 107 ° C. and a toner particle diameter of 6.0 μm in terms of volume-based median diameter.

[Black toner production example 2]
A black toner [2] was prepared in the same manner as in Preparation Example 11 of Orange Toner except that “Carbon Black: Mogal L” was used instead of “Exemplary Compound 5”. The black toner [2] had a softening point temperature (Tsp) of 110 ° C. and a toner particle diameter of 8.0 μm in terms of volume-based median diameter.

(Preparation of developer)
Orange toners [1] to [15], yellow toners [1] and [2], magenta toners [1] and [2], cyan toners [1] and [2], green toners [1] and [2], In addition, each of the black toners [1] and [2] is mixed with a ferrite carrier having a volume average particle diameter of 50 μm coated with methyl methacrylate and cyclohexyl methacrylate resin, and an orange developer [1] to [15] having a toner concentration of 6%. ], Yellow developers [1] and [2], magenta developers [1] and [2], cyan developers [1] and [2], green developers [1] and [2], and black developers [1] and [2] were prepared.

[Examples 1 to 13, Comparative Examples 1 and 2]
A commercially available composite printer “bizhub Pro C500” (manufactured by Konica Minolta Business Technologies) corresponding to the full-color image forming apparatus shown in FIG. 2 was modified and a six-color toner image forming unit was mounted. Each developer was put into a developing unit in the developing means according to the combination of the following, and the following evaluation was performed.

〔Evaluation methods〕
(1) Color reproduction range Under an environment of temperature 20 ° C. and humidity 50% RH, yellow single color (Y), magenta single color (M), cyan single color (C), red (R), blue (B), green (G ) Was formed, each color component was represented by a ^* -b ^* coordinates in the L ^* a ^* b ^* color system, and the color gamut area was measured. The color gamut area was measured with a color gamut area of 100 when the combination of developers shown in Comparative Example 1 was used. Evaluation was performed with a color gamut area of 105. The results are shown in Table 1.

The “L ^* a ^* b ^* color system” is a means that is usefully used to express a color numerically. The L ^* axis direction indicates lightness, and the a ^* axis direction indicates a red-green direction. Represents the hue, and b ^* indicates the hue in the yellow-blue direction. For a ^* and b ^* , a spectrophotometer “Gretag Macbeth Spectrolino” (manufactured by Gretag Macbeth) is used, a D65 light source as a light source, a reflection measurement aperture of φ4 mm, a measurement wavelength region of 380 to 730 nm at 10 nm intervals, The viewing angle is set to 2 °, and measurement is performed under the condition using a dedicated white tile for reference alignment.

(2) Light resistance An orange image with a toner adhesion amount of 0.4 mg / cm ² of 10 cm × 10 cm was formed, and this was used with “Xenon Weather Meter XL75” (manufactured by Suga Test Instruments Co., Ltd.). Irradiation was performed for 480 hours under irradiation conditions, the reflection density of the orange image before and after irradiation was measured, and the rate of change was determined. Evaluation was made with a reflection density change rate of 5% or less as an acceptable level. The results are shown in Table 1.

  The reflection density was measured using a color reflection densitometer “X-Rite 404A” (manufactured by X-Rite), and the change rate before and after irradiation of the reflection density at the maximum absorption wavelength in the wavelength region 380 to 780 nm was obtained. .

  From the results shown in Table 1, in Examples 1 to 13 according to the present invention, compared to Comparative Examples 1 and 2, color unevenness and color turbidity are eliminated and the color reproduction range is expanded. The skin color reproducibility was good due to the expanded reproduction range. Moreover, in Examples 1-13, it was confirmed that the orange image which has the outstanding light resistance is obtained.

10Y, 10Or, 10M, 10C, 10G, 10K Photosensitive drum 11Y, 11Or, 11M, 11C, 11G, 11K Charging means 12Y, 12Or, 12M, 12C, 12G, 12K Exposure means 13Y, 13Or, 13M, 13C, 13G, 13K developing means 14Y, 14Or, 14M, 14C, 14G, 14K primary transfer means 141Y, 141Or, 141M, 141C, 141G, 141K primary transfer roller 14S secondary transfer means 141S secondary transfer roller 17 intermediate transfer members 17a, 17b, 17c Support roller 17d Backup roller 18 Fixing device 181 Heating roller 182 Pressure roller 20Y, 20Or, 20M, 20C, 20G, 20K Cleaning means 20S Intermediate transfer member cleaning means 30Y, 30Or, 30M, 30C 30G, 30K toner image forming units (image forming means)
P transfer material

Claims (5)

A method for forming a full-color image using at least six colors of electrostatic charge image developing toners each containing a binder resin and a colorant,
The six color electrostatic image developing toners are yellow toner, magenta toner, cyan toner, orange toner, green toner and black toner,
A full-color image forming method, wherein the colorant contained in the orange toner is at least one selected from polycyclic quinone pigments represented by the following general formula (1), (2) or (3).

(In the general formulas (1), (2) and (3), X represents a chlorine atom, a bromine atom or an iodine atom, n represents an integer of 0 to 4, and m represents an integer of 0 to 6.)   The colorant contained in the orange toner is C.I. I. Pigment red 168, C.I. I. Pigment orange 19, C.I. I. The full-color image forming method according to claim 1, wherein the full-color image forming method is any one of vat reds 37.   The colorant contained in the orange toner is C.I. I. 3. The full-color image forming method according to claim 1, wherein the full-color image forming method is Pigment Red 168.   The orange toner is prepared by mixing a dispersion liquid in which fine particles of a colorant are dispersed in an aqueous medium and a dispersion liquid in which fine particles of a binder resin are dispersed in an aqueous medium to obtain the fine particles of the colorant and the binder. The full-color image forming method according to any one of claims 1 to 3, wherein the full-color image forming method is obtained by a process of aggregating and fusing fine particles of a resin.   A full-color image forming apparatus having at least six-color image forming means and an intermediate transfer member, wherein the six-color image forming means includes a yellow toner image, an orange toner image, a magenta toner image, a cyan toner image, and a green toner image. And a black toner image, and the intermediate transfer member sequentially superimposes and transfers the toner images formed by the six-color image forming means to form a full-color toner image. 5. The full-color image forming method according to claim 1, wherein the toner image is collectively transferred to a transfer material, and the image forming unit that forms the orange toner image is used in the full-color image forming method according to claim 1. A full-color image forming apparatus using an orange toner.

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