JP2012203078A - Toner for forming image, two-component developer, method for forming image, image forming apparatus and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner having a wide color reproduction range, two-component developer using the toner, a method for forming an image using a toner for forming an image, an image forming apparatus, and a process cartridge.SOLUTION: A toner for forming an image is formed by dispersing an oil phase containing at least a binder resin and a colorant into an aqueous medium and granulating it. The colorant is formed by surface-treating a hydrophilic colorant in an organic solvent with emulsifier obtained by esterification reaction of a polyhydric alcohol with a monovalent fatty acid.

Description

  The present invention relates to an image forming toner having a wide color reproduction range, a two-component developer using the toner, an image forming method, an image forming apparatus, and a process cartridge using the toner.

The image quality of images output by image forming apparatuses has been increasing year by year. For this reason, higher image quality is desired for the output image of the image forming apparatus. With this higher image quality, technically stricter conditions are required. In particular, in recent years when an electrophotographic system is being used for on-demand digital printing, it is necessary to output a high-quality image equivalent to or exceeding that of offset printing.
This also makes it difficult to design pigments that greatly affect the color reproduction range of images, even in performance required for high image quality. In the background, there are technical limitations on the pigments that can be used in the toner for electrophotography.

As can be seen in the former production method, for example, Patent Document 1 (Japanese Patent No. 4169433), the pulverization method produced toner by melting and kneading the pigment into the resin, and output the image. In particular, various types of pigments could be obtained without being influenced by the chemical properties.
However, as seen in, for example, Patent Document 2 (Japanese Patent No. 4299084), in recent years, a pulverization method with a large amount of CO ₂ emission during production has been avoided from consideration for the environment. More and more are manufactured. In this chemical method, much more materials are used than in the pulverization method. And since it is manufactured in a highly active solution, the material used for the toner including the pigment is technically limited.

On the other hand, pigments having a wide color reproduction range, particularly dye-derived rake pigments as seen in, for example, Patent Document 3 (Patent No. 2,584,450) respond to market demands for higher image quality output. Therefore, it is a useful material. However, lake pigments are produced by reacting a dye with a highly polar inorganic oxide to insolubilize it. For this reason, the obtained pigment is a highly polar material, which not only has an adverse effect on the dispersibility in the toner, but also the lake pigment dissolves in the aqueous solvent during the production of the toner, and the pigment in the toner Problems such as difficulty in controlling the concentration and extra cost for wastewater treatment during production. In particular, the adverse effect on the dispersibility inside the toner is similarly generated even if the pigment is not a lake pigment but a strongly hydrophilic pigment.
As described above, conventionally known lake pigments or hydrophilic pigments have a drawback that their use is limited by the toner production method even if the inherent color reproduction range is wide.

  An object of the present invention is to provide a toner having a wide color reproduction range, a two-component developer using the toner, an image forming method using the toner for image formation, an image forming apparatus, and a process cartridge.

  As a result of intensive studies on image forming toners, the present inventors have found that the above problems can be solved by the following method. That is, in order to solve the above-described problem, the image forming toner, the two-component developer, the image forming method using the toner, the image forming apparatus, or the process cartridge according to the present invention are specifically described in the following (1) to (1) to It has the technical feature as described in (11).

(1) A toner obtained by dispersing and granulating an oil phase containing at least a binder resin and a colorant in an aqueous medium,
The image forming toner according to claim 1, wherein the colorant is obtained by surface-treating a hydrophilic colorant in an organic solvent with an emulsifier obtained by an ester reaction of a polyhydric alcohol and a monovalent fatty acid.
(2) The toner for image formation as described in (1) above, wherein the hydrophilic colorant is a pigment obtained by lake conversion of a dye.
(3) The image forming toner as described in (1) or (2) above, wherein the hydrophilic colorant is a pigment obtained by lake conversion of a rhodamine dye.
(4) The image forming toner according to any one of (1) to (3), wherein the emulsifier is obtained by an ester reaction of glycerin and stearic acid.
(5) The surface treatment with the emulsifier is performed in the range of 10 to 100 parts by weight of the emulsifier with respect to 100 parts by weight of the hydrophilic colorant, according to any one of (1) to (4), Toner for image formation.
(6) A two-component developer comprising the image forming toner according to any one of (1) to (5) and a carrier.
(7) A charging step for charging at least the surface of the image carrier, an electrostatic latent image forming step for forming an electrostatic latent image on the image carrier, and developing the visible image with toner to make it visible An image forming method comprising: a developing step for forming an image; a transfer step for transferring the visible image onto a recording medium to form an unfixed image; and a fixing step for fixing the unfixed image on the recording medium. An image forming method, wherein the toner used to form the visible image is the image forming toner according to any one of (1) to (5).
(8) The image forming method according to (7), wherein a conveyance speed of the recording medium in the fixing step is 280 mm / second or more.
(9) At least the image carrier, charging means for charging the surface of the image carrier, exposure means for exposing the charged image carrier surface to form an electrostatic latent image, and the electrostatic latent image Developing means for developing a visible image by using toner, transfer means for transferring the developed toner image onto a recording medium to form an unfixed image, and fixing the unfixed image to the recording medium An image forming apparatus including the fixing unit, wherein the toner used to form the visible image is the image forming toner according to any one of (1) to (5). An image forming apparatus.
(10) The image forming apparatus according to (9), wherein a conveyance speed of the recording medium at the time of fixing by the fixing unit is 280 mm / second or more.
(11) an image carrier, charging means for charging the surface of the image carrier, exposure means for exposing the charged image carrier surface to form an electrostatic latent image, and forming the electrostatic latent image into toner And at least one means selected from a developing means for developing using toner, a transferring means for transferring the developed toner image to a recording medium, and a cleaning means for removing toner remaining on the surface of the image carrier after transfer. A process cartridge that can be attached to and detached from the main body of the image forming apparatus, and has a developing unit that develops the formed electrostatic latent image using toner, and the toner to be used is the above (1) to (1). (5) A process cartridge, which is the image forming toner according to any one of (5).

According to the toner of the present invention and the two-component developer using the toner, an electrophotographic image forming apparatus having a wide color reproduction range and capable of outputting an image with significantly higher image quality than before. It is.
According to the image forming apparatus of the present invention, since the excellent image forming toner capable of outputting a high-quality image is used, it is possible to output a high-quality and stable image even when the process linear speed is high.
The image forming method and the image forming apparatus of the present invention can be widely applied to electrophotographic application fields using electrophotography (for example, electrostatic copying machines, laser beam printers, etc.).
Further, according to the process cartridge of the present invention, since the toner of the present invention is supplied from the developing means, an excellent image capable of outputting a high-quality image can be output.

It is a schematic explanatory drawing of an example of the image forming apparatus of this invention. It is a schematic explanatory drawing of the other example of the image forming apparatus of this invention. It is a schematic explanatory drawing of the other example of the image forming apparatus of this invention. FIG. 4 is a partially enlarged schematic explanatory diagram of the image forming apparatus shown in FIG. 3. It is a schematic explanatory drawing of an example of the process cartridge of this invention.

Details of the present invention will be described below, but the present invention is not limited thereto.
The toner of the present invention is a toner obtained by dispersing and granulating an oil phase containing at least a binder resin and a colorant in an aqueous medium,
The colorant is obtained by surface-treating a hydrophilic colorant in an organic solvent with an emulsifier obtained by an ester reaction of a polyhydric alcohol and a monovalent fatty acid.
However, the hydrophilic colorant is a colorant whose subsidence is observed on the bottom when 5 g of water is added to a 10 mL transparent glass vial, 0.1 g of the colorant is added from above and left to stand for 1 hour. Say. This also applies to dyes, lake pigments, and organic pigments, which are described as “hydrophilic” hereinafter.
That is, a hydrophilic colorant that originally has a wide color reproduction range is used to enable output of a high-quality image.
In addition, even when the hydrophilic colorant elutes in an aqueous solvent and is not encapsulated in the toner, or cannot be uniformly dispersed inside the toner due to the hydrophilicity of the hydrophilic colorant, the surface treatment is prevented from being eluted by the emulsifier or evenly dispersed. The coloring agent which gave is used.

(Use of hydrophilic colorants in chemical toners)
The toner produced in the aqueous medium contains various materials that are not used for the pulverized toner. Since the liquidity of the aqueous medium differs depending on these materials, the hydrophilic colorant is adversely affected by its polarity. For example, pigments raked with dyes represented by Pigment Red 48, 57, 81, etc. (hereinafter also referred to as dye laked pigments), Pigment Yellow 74, 139, 180, 185, Pigment Blue 15: 3, Pigment Red 122 184, 269, or a colorant obtained by hydrophilic treatment of these materials may not be encapsulated in the toner but may elute into the aqueous medium, or may not be uniformly dispersed in the toner. That is, there is a case where even a colorant having a potential capable of exhibiting a wide color reproducibility cannot be used as it is.

  By treating these hydrophilic colorants with an emulsifier in an organic solvent, the hydrophilic colorant can be used in an aqueous medium. This treatment must be performed in advance as a pretreatment step for emulsifying the toner in an organic solvent. By preliminarily treating the emulsifier, it is possible to improve the wettability of the surface of the colorant and to obtain an effect that the colorant is as close to the primary particle size as possible. For example, when this surface treatment is not performed, the aggregation of hydrophilic colorant particles occurs, resulting in a problem that color reproducibility is lowered and desired characteristics cannot be obtained.

  Moreover, it is important that the emulsifier used for the surface treatment is an emulsifier obtained by an ester reaction of a polyhydric alcohol and a monovalent fatty acid. The emulsifier obtained by this combination is characterized in that it is used in an organic solvent so that a more hydrophilic material is wrapped inside and the organic solvent is present on the outside to disperse the material. Therefore, for example, a hydrophilic lake pigment such as rhodamine can adsorb the emulsifier on the surface of the pigment in an organic solvent containing an emulsifier obtained by an ester reaction of a polyhydric alcohol and a monovalent fatty acid. Thus, by using a hydrophilic colorant that has been previously treated with this emulsifier, it is possible to inhibit the hydrophilic colorant from coming into direct contact with the aqueous medium when the toner is produced. It is possible to protect against adverse effects such as uneven distribution on the surface of the toner and causing problems.

  Furthermore, when the colorant dispersion state is poor, there is a possibility that the fixing property of the toner to a medium such as paper may be hindered. The surface of the toner is overheated in the image forming apparatus and is fixed on the medium with a margin to form an image. If the colorant is unevenly distributed on the surface, the heat is transferred well to the toner. In other words, since it does not melt, a fixing failure occurs, resulting in a defect in the image. Also, the higher the output speed of the image forming apparatus, the less likely heat is transferred to the toner. For this reason, in an image forming apparatus capable of high-speed output, compared with the case where the colorant is unevenly distributed on the surface of the toner, the toner with good colorant dispersion has a remarkable effect of improving the image quality.

Examples of the emulsifier include all known esters obtained by dehydration condensation of a polyhydric alcohol and a monovalent fatty acid.
Examples of the polyhydric alcohol include polyhydric alcohols having 2 to 4 carbon atoms (for example, ethylene glycol, propylene glycol, butylene glycol), glycerin having 3 to 12 carbon atoms (tetramer), A glycerin polymer (dehydrated polymer) is desirable. Moreover, if it is saccharides, disaccharides like sucrose (sucrose) are desirable.
As the OH (alcohol value) number of the polyhydric alcohol, the number of alcohols after esterifying the fatty acid is preferably 0 to 6.
The monovalent fatty acid is preferably a solid that dissolves the resulting emulsifier at about 60 ° C., and monovalent saturated and unsaturated fatty acids having 15 to 25 carbon atoms are preferred. For example, examples of the saturated fatty acid include palmitic acid, stearic acid, arachidic acid, and behenic acid, and examples of the unsaturated fatty acid include oleic acid, linoleic acid, linolenic acid, and the like.

  In particular, glycerin or glycerin dehydrated polymer and esters of fatty acids (eg glycerin, monoglyceryl monostearate, monoglyceryl distearate, monoglyceryl tristearate, diglyceryl monostearate, diglyceryl distearate, diglyceryl tris) Stearate, diglyceryl tetrastearate, triglycerin, triglyceryl monostearate, triglyceryl distearate, triglyceryl tristearate, triglyceryl tetrastearate, triglyceryl pentastearate, tetraglyceryl, tetraglyceryl monostearate Tetraglyceryl distearate, tetraglyceryl tristearate, tetraglyceryl tetrastearate, tetraglyceryl pentastearate, Lug glyceryl hexastearate), and esters of sucrose and fatty acids are preferred, still more preferably an ester of stearic acid or behenic acid was added and the two molecules dehydrated to tetraglycerol 1 molecule. In the surface treatment method of the present invention, it is necessary to use an emulsifier whose hydrophobicity is appropriately controlled, and thus esters of glycerin and fatty acids are one of the most suitable materials for the conditions of the present invention, Another reason is that the HLB value can be easily adjusted by the amount of fatty acid dehydrated and added.

(Treatment concentration of emulsifier for hydrophilic colorant)
The treatment concentration of the emulsifier with respect to the hydrophilic colorant varies depending on the hydrophilicity of the hydrophilic colorant used, but is in the range of 10 to 100 parts by weight of the emulsifier with respect to 100 parts by weight of the hydrophilic colorant. The amount is preferably 15 to 30 parts by weight. This is because it is related to the surface area of the hydrophilic colorant. If the amount is less than 10 parts by weight, the surface of the hydrophilic colorant is not exposed to the emulsifier and the surface of the hydrophilic colorant is exposed, and can be in sufficient contact with the aqueous medium, so that elution of the colorant or uneven dispersion in the toner There are cases where the adverse effects cannot be suppressed. Moreover, since the addition amount of 10 parts by weight or more can suppress “wetting” by the aqueous medium on the surface of the hydrophilic colorant, the addition amount is preferably more than that. In addition, by gradually increasing the amount of addition, the surface of the hydrophilic colorant is almost completely covered with the emulsifier, and at 15 parts by weight or more, the coverage of the surface of the hydrophilic colorant with respect to the surface area of the emulsifier is increased. It is estimated that it becomes 100% or more. Therefore, theoretically, the surface of the hydrophilic colorant is completely covered with the emulsifier, and the effect of preventing the wetness of the aqueous medium is most enhanced, which is most preferable. However, when the addition amount is higher than 100 parts by weight, the dispersion state of the colorant in the toner can be made uniform, but the intensity of absorption and reflection light peculiar to the pigment is weakened by scattering by the surface treatment emulsifier, and the image quality is increased. There is a risk of lowering. More preferably, it is 30 parts by weight or less.

(Stirrer for surface treatment and treatment conditions)
When treating the emulsifier on the surface of the hydrophilic colorant, a known disperser, for example, a general paint shaker that disperses using zirconia beads, a starburst series that is a wet disperser (manufactured by Sugino Machine), Nanomizer (manufactured by Yoshida Kikai Kogyo Co., Ltd.), TK homomixer (manufactured by PRIMIX) and the like.
In the present invention, surface treatment was performed by a paint shaker using zirconia beads. When the surface treatment of the pigment is actually performed, for example, when 400 parts by weight of ethyl acetate is added to 100 parts by weight of the pigment, 500 parts by weight of the zirconia beads are added in the same amount as the liquid amount, and stirring is continued for 15 hours or more. It is desirable.

(Organic solvent for surface treatment)
The organic solvent used for the pigment surface treatment can be any organic solvent that is generally known below, and is volatile with a boiling point of less than 100 ° C. It is preferable because it is easy. Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, Methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable.
However, it is more preferable to select the same type of organic solvent together with the toner granulating liquid (oil phase) used when the toner is granulated, and the concentration of the organic solvent added to the weight part of the pigment is: The concentration is preferably the same as that of the oil phase. This is because when the type and concentration of the organic solvent is different, when preparing the toner granulation liquid, the surface treatment may be removed or the surface condition may change due to mass transfer due to the concentration difference. This is to prevent it.

(Coloring agent)
Examples of the hydrophilic colorant used in the image forming toner of the present invention include a hydrophilic pigment, or a pigment obtained by lake-forming a dye.

  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, bengara, red lead, red lead, cadmium red, cadmium mercury red, antimony red, permanent red 4R, para red, phise red, parachlor ortho nitroaniline red, risor fast scarlet G, Reliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pogment 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, quinacridone red, pyrazolone red, polyazo red, chrome vermilion, benzidine Range, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo , Ultramarine, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt violet, manganese violet, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridiane, emerald green, pigment green B, naphthol green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalocyanine Green, Anthraquinone Green, Oxidized Chi Tan, zinc white, litbon and mixtures thereof. In addition, it is also possible to use those colorants that have been subjected to a hydrophilic treatment by a known method such as introduction of a functional group, if necessary.

Among them, an example of a pigment that has been raked is given as a color index number. For example, as a pigment obtained by lacquering a dye, yellow is PY61, PY62, PY133, PY168, PY169, PY205, PY206, PY209, PY212, magenta or red is PR48 (: 1 to 3), PR52, PR57, PR58. , PR63, PR64, PR81 (: 1 to 4), PR200, PR211, PR243, PR247 as blue or violet, PV3, PV27, PV39, PB1, PB2, PB9, PB10, PB14, PB62, green include PGr1, PGr4, PGr45, etc. are mentioned.
The content of the colorant is usually 1 to 15% by weight based on the image forming toner.

In the present invention, whether the hydrophilic colorant is hydrophilic was determined by the following method.
(Hydrophilicity inspection method)
A 10 ml vial was charged with 5 g of ion exchanged water, then 0.1 g of a pre-weighed pigment was added and left for 1 hour. At this time, the pigment particles falling to the bottom of the vial were judged to be hydrophilic.

(Manufacturing method of masterbatch)
The colorant after the surface treatment may be used as a wet masterbatch by preparing a varnish combined with a resin. The resin is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, styrene or a substituted polymer thereof, a styrene copolymer, 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 hydrocarbon resin, alicyclic ring Aromatic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin, and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the polymer of styrene or a substituted product thereof include polyester resin, polystyrene, poly p-chlorostyrene, polyvinyl toluene, and the like. Examples of the styrene copolymer include a styrene-p-chlorostyrene copolymer, a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, a styrene-vinylnaphthalene copolymer, and a styrene-methyl acrylate copolymer. Polymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene- Butyl methacrylate copolymer, styrene-p-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene An acrylonitrile-indene copolymer, Styrene - maleic acid copolymer, styrene - maleic acid ester copolymer, and the like.

(Other materials)
If necessary, the toner of the present invention may contain a release agent, a charge control agent, an external additive and the like as long as the effects of the present invention are not impaired.

(Release agent)
There is no restriction | limiting in particular as a mold release agent used for the toner for image formation of this invention, According to the objective, it can select suitably from well-known things, For example, waxes etc. are mentioned suitably. The melting point of the wax as the release agent is preferably 70 to 150 ° C. When the temperature is lower than 70 ° C., the heat resistant storage stability of the toner is inferior. When the temperature is higher than 150 ° C., the releasability cannot be sufficiently achieved and the toner fixing property is inferior. The amount of these release agents used is preferably 2 to 15% by weight based on the toner. If it is less than 2% by weight, the effect of preventing offset is insufficient, and if it exceeds 15% by weight, transferability and durability are deteriorated.

A conventionally well-known thing can be used for the said wax. For example, low molecular weight polyethylene, low molecular weight polypropylene and other low molecular weight polyolefin waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax, beeswax, carnauba wax, candelilla wax, rice wax, montan wax and other natural waxes, Examples include petroleum waxes such as paraffin wax and microcrystalline wax, higher fatty acids such as stearic acid, palmitic acid, and myristic acid, metal salts of higher fatty acids, higher fatty acid amides, synthetic ester waxes, and various modified waxes thereof. These waxes can be used alone or in combination of two or more.
Of these, carnauba wax and its modified wax, polyethylene wax, and synthetic ester wax are preferably used. In particular, the synthetic ester wax pentaerythritol tetrabehenate is most preferred. The reason is that carnauba wax, its modified wax and synthetic ester wax are appropriately finely dispersed with respect to polyester resin and polyol resin, so that it is easy to make a toner excellent in offset prevention, transferability and durability. It is.

(Charge control agent)
As the charge control agent used in the present invention, any conventionally known charge control agent can be used. For example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus Simple substance or compound, tungsten simple substance or compound, fluorine-based activator, salicylic acid metal salt, metal salt of salicylic acid derivative, and the like.

  Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenolic condensate E-89 (above, Orient Chemical Industries, Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy Charge PSY VP2038, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit) Manufactured), copper phthalocyanine, perylene, quinacridone, azo And pigments and other high molecular compounds having functional groups such as sulfonic acid groups, carboxyl groups, and quaternary ammonium salts.

  The content of the charge control agent is appropriately determined according to desired charging characteristics, but is preferably 0.1 to 10% by weight, more preferably 0.2 to 5% by weight, based on the binder resin. . When the addition amount exceeds 10% by weight, the chargeability of the toner is too high, the effect of the charge control agent is reduced, the electrostatic attraction with the developing roller is increased, the flowability of the developer is reduced, the image The concentration may decrease. On the other hand, if the addition amount is less than 0.1% by weight, the charge rising property and the charge amount are not sufficient, and the toner image may be easily affected.

(Binder resin)
The binder resin preferably contains a polyester resin. Monomers constituting the polyester resin for the binder resin include, but are not limited to, the following.
Examples of the divalent alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1 , 6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, diol obtained by polymerizing cyclic ethers such as ethylene oxide and propylene oxide to bisphenol A, and the like. Can be mentioned.

  Examples of acid components that form polyester polymers include benzene dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid, or anhydrides thereof, alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid, or the like. Unsaturated dibasic acids such as anhydride, maleic acid, citraconic acid, itaconic acid, alkenyl succinic acid, fumaric acid, mesaconic acid, maleic anhydride, citraconic anhydride, itaconic anhydride, alkenyl succinic anhydride, etc. Unsaturated dibasic acid anhydrides, and the like.

  Examples of the trivalent or higher polyvalent carboxylic acid component include trimet acid, pyromellitic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1 , 2,4-Naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxy-2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxy ) Methane, 1,2,7,8-octanetetracarboxylic acid, emporic trimer acid, or their anhydrides, partially lower alkyl esters, and the like.

  Further, as the resin used in the present invention, in addition to polyester, all those conventionally used for image forming toners can be used. For example, homopolymers of styrene such as polystyrene, polychlorostyrene, and polyvinyltoluene, and substituted products thereof; styrene / p-chlorostyrene copolymer, styrene / propylene copolymer, styrene / vinyltoluene copolymer, styrene / vinyl Naphthalene copolymer, styrene / methyl acrylate copolymer, styrene / ethyl acrylate copolymer, styrene / butyl acrylate copolymer, styrene / octyl acrylate copolymer, styrene / methyl methacrylate copolymer, Styrene / ethyl methacrylate copolymer, styrene / butyl methacrylate copolymer, styrene / α-chloromethyl methacrylate copolymer, styrene / acrylonitrile copolymer, styrene / vinyl ethyl ether copolymer, styrene / vinyl methyl Ketone copolymer, steel Styrene copolymers such as styrene / butadiene copolymer, styrene / isoprene copolymer, styrene / acrylonitrile / indene copolymer, styrene / maleic acid copolymer, styrene / maleic acid ester copolymer; polymethyl methacrylate , Polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyvinyl butyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic A group petroleum resin, chlorinated paraffin, paraffin wax and the like can be mentioned, and these are used alone or in admixture of two or more.

(Molecular weight of the resin used)
In the image forming toner of the present invention, the weight average molecular weight (Mw) of the binder resin (for example, polyester resin) in the toner is obtained in order to achieve both low temperature fixability and heat resistant storage stability and appropriate gloss (glossiness). Is preferably about 1,000 to 500,000. Note that the number average molecular weight (Mn) may be measured instead of the weight average molecular weight.
The weight average molecular weight (Mw) or the number average molecular weight (Mn) can be measured as follows.

(Measurement of weight average molecular weight (Mw) of resin)
The weight average molecular weight (Mw) of the binder resin is measured by GPC (gel permeation chromatography) under the following conditions.
・ Apparatus: GPC-150C (manufactured by Waters)
Column: KF801-807 (manufactured by Shodex)
・ Temperature: 40 ℃
・ Solvent: THF (tetrahydrofuran)
・ Flow rate: 1.0 mL / min ・ Sample: 0.1 mL injection of a sample with a concentration of 0.05 to 0.6% Molecular weight prepared from a monodisperse polystyrene standard sample from the molecular weight distribution of the binder resin measured under the above conditions The mass average molecular weight of the binder resin is calculated using the calibration curve.

(Measurement of number average molecular weight (Mn))
The number average molecular weight of the binder resin is measured by GPC under the following conditions.
・ Apparatus: GPC-150C (manufactured by Waters)
Column: KF801-807 (manufactured by Shodex)
・ Temperature: 40 ℃
・ Solvent: THF (tetrahydrofuran)
Flow rate: 1.0 mL / min Sample: Inject 0.1 mL of a sample having a concentration of 0.05 to 0.6%.
Further, when the insoluble content when 1 g of a sample (binder resin) is added to 100 ml of THF is 75% by weight or more, DMF (dimethylformamide) is used as a solvent. The number average molecular weight is calculated from a molecular weight calibration curve prepared using a monodisperse polystyrene standard sample.

(External processing)
The toner of the present invention can be granulated by a polymerization method obtained by emulsifying, dissolving and suspending in an aqueous medium. In order to improve the fluidity, storage stability, developability, and transferability of the toner, inorganic fine particles (external additives) may be further added and mixed with the manufactured toner base particles. For mixing such additives, a general powder mixer is used, but it is preferable to equip a jacket or the like to adjust the internal temperature. In order to change the load history applied to the additive, the additive may be added midway or gradually. In this case, you may change the rotation speed, rolling speed, time, temperature, etc. of a mixer. Alternatively, a strong load may be applied first, then a relatively weak load, or vice versa. Examples of the mixing equipment that can be used include a V-type mixer, a rocking mixer, a Ladige mixer, a Nauter mixer, and a Henschel mixer. Next, the toner is obtained by passing through a sieve of 250 mesh or more to remove coarse particles and aggregated particles.

(External additive)
As the external additive used in the present invention, inorganic fine particles are preferably used for the purpose of imparting fluidity, chargeability and developability. The primary particle diameter of the inorganic fine particles is preferably 5 × 10 ^-3 ~2μm, it is particularly preferably 5 × 10 ^-3 ~0.5μm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The amount of the inorganic fine particles added is preferably 0.01 to 5 wt% of the image forming toner.

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, silica sand, clay, mica, wollastonite, Examples thereof include diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.
Such external additives can be surface treated to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having an alkyl fluoride group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferable surface treatment agents. .

  The weight average particle diameter of the image forming toner of the present invention is not particularly limited and can be appropriately selected according to the purpose. However, in order to obtain a high-quality image having excellent granularity, sharpness, and fine line reproducibility. The weight average particle diameter is preferably 3.5 μm to 10 μm. The smaller the particle size, the better the image sharpness and fine line reproducibility. In particular, in a color image forming apparatus, a demand for image quality is strict and a toner of 10 μm or less is required. In particular, 7.5 μm or less is preferable for image quality. On the other hand, if the toner particle diameter is too small, such as less than 3.5 μm, the toner fluidity and transferability deteriorate. Here, the weight average particle diameter of the toner can be obtained as follows.

(Measurement of weight average particle diameter (Dw) of toner)
As an apparatus for measuring the particle size distribution of toner particles by the Coulter counter method, there are Coulter Counter TA-II and Coulter Multisizer III (both manufactured by Coulter). In the present invention, measurement was performed as follows using Coulter Multisizer III.
First, 0.1 to 5 ml of a surfactant, preferably polyoxyethylene alkyl ether, is added as a dispersant to 100 to 150 ml of an electrolytic aqueous solution. Here, the electrolytic solution is an about 1% NaCl aqueous solution prepared using primary sodium chloride, and for example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as an aperture. Volume distribution and number distribution are calculated. From the obtained distribution, the weight average particle diameter (Dw) and the number average particle diameter (Dn) of the toner can be obtained.
The channel in the above measurement is as follows: 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to 6.35 μm Less than 6.35 to less than 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; ≦ 25.40 μm; 25.40 to less than 32.00 μm; 13 channels of 32.00 to less than 40.30 μm are used, and particles having a particle diameter of 2.00 μm to less than 40.30 μm are targeted.

  The image forming toner of the present invention can be used as a one-component developer or a two-component developer. That is, the one-component developer is composed of only the image forming toner, and the two-component developer is composed of the image forming toner and the carrier.

(Two-component developer)
As the carrier used in the two-component developer of the present invention, conventionally known ones for two-component developers can be used. For example, a carrier made of magnetic particles such as iron or ferrite, a resin-coated carrier in which such magnetic particles are coated with a resin, or a binder-type carrier in which magnetic fine powder is dispersed in a binder resin. Can be used.
Magnetic materials include iron oxides such as magnetite, hematite, and ferrite, metals such as iron, cobalt, and nickel, or aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, Metal alloys such as calcium, manganese, selenium, titanium, tungsten, vanadium and mixtures thereof can be used.

  Among these carriers, a silicone resin, a copolymer resin (graft resin) of an organopolysiloxane and a vinyl monomer, or a resin-coated carrier using a polyester resin can be used as a coating resin, such as toner spent. A carrier coated with a resin obtained by reacting an isocyanate with a copolymer resin of an organopolysiloxane and a vinyl monomer is preferable from the viewpoint of durability, environmental stability, and spent resistance. . As the vinyl monomer, it is necessary to use a monomer having a substituent such as a hydroxyl group reactive with isocyanate.

  In addition to the above, examples of carrier coating materials used for carriers include amino resins such as urea-formaldehyde resins, melamine resins, benzoguanamine resins, urea resins, polyamide resins, and epoxy resins. Polyvinyl and polyvinylidene resins, acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and polystyrene resins such as styrene-acrylic copolymer resins, poly Halogenated olefin resins such as vinyl chloride, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoropropylene Resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and fluoride Vinylidene fluoro such as terpolymers of non-fluorinated monomer, and silicone resins.

Moreover, you may make conductive powder etc. contain as a filler in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide, aluminum oxide, silica and the like can be used. These preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it is difficult to control electric resistance in the case of conductive powder.
It is preferable to use a magnetic carrier having a volume average particle diameter of 20 to 100 μm, preferably 20 to 60 μm from the viewpoint of ensuring high image quality and preventing carrier fogging.

(Production example of polymerized toner)
When the toner of the present invention is produced in an aqueous medium (polymerized toner), first, the above colorant, unmodified polyester, polyester prepolymer (A) having an isocyanate group, and a release agent are dispersed in an organic solvent. Make a toner material liquid (oil phase). It is preferable that a polyester prepolymer (A) having an isocyanate group is added to the toner material liquid and reacted during granulation to contain the urea-modified polyester resin in the toner.

(Polyester prepolymer having isocyanate group (A))
For example, the polyester prepolymer is reacted with a polyvalent isocyanate compound (PIC) with a carboxyl group or a hydroxyl group at the end of the polyester obtained by polycondensation reaction of polyhydric alcohol (PO) and polycarboxylic acid (PC). Polyester prepolymer (A) having an isocyanate group is preferably used.

  Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable. Examples of the dihydric alcohol (DIO) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among these, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols. The trihydric or higher polyhydric alcohol (TO) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

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

  Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.) ); Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; phenol derivatives, oximes, polyisocyanates; Those blocked with caprolactam or the like; and combinations of two or more of these.

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

(Organic solvent)
The organic solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal after toner base particle formation. Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, Methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. The usage-amount of an organic solvent is 0-300 weight part normally with respect to 100 weight part of polyester prepolymers, Preferably it is 0-100 weight part, More preferably, it is 25-70 weight part.

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

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

  Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-Hydroxyethyl) Perful Olooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Can be mentioned.

  Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Daikin Industries, Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (manufactured by Dainippon Ink, Inc.), Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).

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

(Resin fine particles)
As the resin fine particles, any resin can be used as long as it can form an aqueous dispersion, and it may be a thermoplastic resin or a thermosetting resin. Examples thereof include vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, and polycarbonate resins. As the resin, two or more of the above resins may be used in combination.

  Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferred because an aqueous dispersion of fine spherical resin particles is easily obtained. For example, vinyl resins are polymers obtained by homopolymerization or copolymerization of vinyl monomers, such as styrene- (meth) acrylic acid ester copolymers, styrene-butadiene copolymers, (meth) acrylic acid-acrylic acid esters. Examples thereof include resins such as a polymer, a styrene-acrylonitrile copolymer, a styrene-maleic anhydride copolymer, and a styrene- (meth) acrylic acid copolymer. The average particle size of the resin fine particles is 5 to 200 nm, preferably 20 to 300 nm. In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.

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

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

Examples of the amines (B) include diamine (B1), triamine or higher polyamine (B2), amino alcohol (B3), amino mercaptan (B4), amino acid (B5), and (B1) to (B5). Examples thereof include an amino group blocked (B6).
Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexylmethane, diamines). Cyclohexane, isophoronediamine, etc.); and aliphatic diamines (ethylenediamine, tetramethylenediamine, hexamethylenediamine, etc.) and the like.
Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid.
As (B6) which blocked the amino group of (B1) to (B5), ketimine compounds obtained from the amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) of (B1) to (B5), Examples include oxazoline compounds. Among these amines (B), preferred are (B1) and a mixture of (B1) and a small amount of (B2).

  The ratio of amines (B) is equivalent to the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the polyester prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). Is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] exceeds 2 or less than 1/2, the molecular weight of the urea-modified polyester becomes low, and the hot offset resistance deteriorates.

Since this reaction involves crosslinking and / or elongation of molecular chains, a reaction terminator can be used as necessary to adjust the molecular weight of the resulting urea-modified polyester. Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).
The reaction time is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

  The weight ratio of unmodified polyester to urea-modified polyester is usually 20/80 to 95/5, preferably 70/30 to 95/5, more preferably 75/25 to 95/5, and particularly preferably 80 /. 20-93 / 7. When the weight ratio of the urea-modified polyester is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

(Removal of organic solvent, washing, drying)
After completion of the reaction, the organic solvent is removed from the emulsified dispersion (reactant), washed and dried to obtain toner base particles.
In order to remove the organic solvent, the temperature of the entire system is gradually raised in a laminar stirring state, and after giving strong stirring in a certain temperature range, the solvent base is removed to produce spindle-shaped toner base particles. . Further, when an acid such as calcium phosphate salt or an alkali-soluble material is used as the dispersion stabilizer, the calcium phosphate salt is dissolved from the toner base particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. Remove. It can also be removed by operations such as enzymatic degradation. A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are adhered to the base particles as external additives to obtain a toner. The charge control agent is injected and the inorganic fine particles are externally added by a known method using a mixer or the like.
Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the true spherical shape and the rugby ball shape can be controlled, and the surface morphology is also controlled between the smooth shape and the umeboshi shape. be able to.

(Binder resin content in the toner)
The content of the binder resin in the toner is desirably 80 to 95 parts by weight with respect to 100 parts by weight of the toner. If the amount is less than 80 parts by weight, the content of other materials may increase, causing problems in fixability and chargeability. If the amount is more than 95 parts by weight, the coloring power is reduced, resulting in image quality. May fall.

(Inspection of elution into aqueous media)
The granulated aqueous solvent was put into a quartz cell having a layer thickness of 1 cm, and the transmittance at a spectral wavelength of 700 nm to 400 nm was measured with a V-650DS spectrophotometer manufactured by JASCO Corporation. At this time, when the yellow colorant had a transmittance of 450 nm, the magenta colorant had a transmittance of 550 nm, and the cyan colorant had a transmittance of 650 nm of 80% or less, it was determined that it was eluted.

(Image forming method)
The image forming method of the present invention comprises at least a charging step for charging the surface of an image carrier, an electrostatic latent image forming step for forming an electrostatic latent image on the image carrier, and the electrostatic latent image for image formation. A development process for forming a visible image by developing with toner, a transfer process for transferring the visible image onto a recording medium to form an unfixed image, and fixing the unfixed image on the recording medium The image forming method includes a fixing step, and the image forming toner used for forming the visible image is the image forming toner described above. Here, the toner for image formation can be satisfactorily fixed even if the conveyance speed of the recording medium in the fixing step is 280 mm / second or more.

Next, the image forming method of the present invention will be described with reference to the drawings. The image forming apparatus shown in FIG. 1 includes a photosensitive member 10, a charging device 20, an exposure device 30, a developing device 40, an intermediate transfer member 50, a cleaning device 60 having a cleaning blade, a charge eliminating device 70, a transfer device. A device 80 is provided. Note that a charging roller is used as the charging device 20, a static elimination lamp as the static elimination device 70, and a transfer roller as the transfer device 80.
The intermediate transfer member 50 is an endless belt, and is designed to be stretched by three support rollers 51 arranged on the inner side thereof so as to be movable in the arrow direction. A part of the three support rollers 51 also functions as a transfer bias roller capable of applying a predetermined transfer bias (primary transfer bias) to the intermediate transfer member 50. The intermediate transfer member 50 is provided with a cleaning device 90 having a cleaning blade in the vicinity thereof. Further, a transfer device 80 capable of applying a secondary transfer bias for transferring a visible image (secondary transfer) to the transfer target 95 is disposed opposite to the transfer device 80. Around the intermediate transfer member 50, a corona charger 58 for applying a charge to the visible image on the intermediate transfer member 50 is in contact with the photosensitive member 10 and the intermediate transfer member 50 in the rotation direction of the intermediate transfer member 50. And the contact portion between the intermediate transfer body 50 and the transfer body 95.
Note that transfer paper is used as the transfer target 95.

  The developing device 40 includes a developing belt 41 as a developer carrier, and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C provided around the developing belt 41. ing. The developing unit 45K includes a developer accommodating portion 42K, a developer supplying roller 43K, and a developing roller 44K, and the developing unit 45Y includes a developer accommodating portion 42Y, a developer supplying roller 43Y, and a developing roller 44Y. The developing unit 45M includes a developer accommodating portion 42M, a developer supply roller 43M, and a developing roller 44M. The developing unit 45C includes a developer accommodating portion 42C, the developer supplying roller 43C, and the developing roller 44C. Yes. The developing belt 41 is an endless belt, is rotatably stretched around a plurality of belt rollers, and a part thereof is in contact with the photoconductor 10.

In this image forming apparatus, after the charging device 20 uniformly charges the photoconductor 10, the exposure device 30 performs imagewise exposure on the photoconductor 10 to form an electrostatic latent image. Next, the developing device 40 supplies the developer to the electrostatic latent image formed on the photoconductor 10 and develops it to form a visible image.
The visible image is transferred (primary transfer) onto the intermediate transfer body 50 by the voltage applied from the support roller 51 and further transferred (secondary transfer) onto the transfer body 95. As a result, a transfer image is formed on the transfer target 95. The toner remaining on the photoconductor 10 is removed by the cleaning device 60, and the charge of the photoconductor 10 is removed by the charge eliminating lamp 70.

  Next, another aspect of the image forming method of the present invention will be described with reference to FIG. The image forming apparatus shown in FIG. 2 has a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan around the photosensitive member 10, instead of the developing device 40 in the image forming apparatus shown in FIG. The developing unit 45C has the same configuration as that of the image forming apparatus shown in FIG. In FIG. 2, the same components as those in the image forming apparatus shown in FIG. The same applies to FIGS. 3 and 4 described later.

Next, another aspect of the image forming method of the present invention will be described with reference to FIG. The image forming apparatus shown in FIG. 3 is a tandem type color image forming apparatus. The image forming apparatus includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.
The copying apparatus main body 150 is provided with an endless belt-like intermediate transfer member 50 at the center. The intermediate transfer member 50 is stretched around the support rollers 14, 15, and 16 and can rotate clockwise in FIG. 3. A cleaning device 17 for removing residual toner on the intermediate transfer member 50 is disposed in the vicinity of the support roller 15. On the intermediate transfer member 50 stretched by the support roller 14 and the support roller 15, four image forming units 18 of yellow, cyan, magenta, and black are arranged opposite to each other along the conveying direction. A means 120 is arranged. An exposure device 21 is disposed in the vicinity of the image forming unit 120. The secondary transfer device 22 is disposed on the side of the intermediate transfer member 50 opposite to the side on which the image forming unit 120 is disposed. In the secondary transfer device 22, a secondary transfer belt 24, which is an endless belt, is stretched around a pair of support rollers 23, and the recording paper conveyed on the secondary transfer belt 24 and the intermediate transfer member 50 are mutually connected. It is possible to touch. A fixing device 25 is disposed in the vicinity of the secondary transfer device 22. The fixing device 25 includes a fixing belt 26 that is an endless belt and a pressure roller 27 that is pressed against the fixing belt 26. In addition, a reversing device 28 for reversing the recording paper in order to form images on both sides of the recording paper is disposed in the vicinity of the secondary transfer device 22 and the fixing device 25.

Next, formation of a full-color image (color copy) using the image forming unit 120 will be described. First, an original document is set on the document table 130 of the automatic document feeder (ADF) 400 or the automatic document feeder 400 is opened, and the original document is set on the contact glass 32 of the scanner 300. Close.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the contact glass 32. When this happens, the scanner 300 is immediately driven, and the first traveling body 33 and the second traveling body 34 travel. At this time, light from the light source is irradiated by the first traveling body 33, and reflected light from the document surface is reflected by a mirror in the second traveling body 34. Further, the image is received by the reading sensor 36 through the imaging lens 35, and the original is read to obtain image information of black, yellow, magenta and cyan. Next, each image information is transmitted to each image forming unit 18 in the image forming means 120, and a visible image of each color of black, yellow, magenta and cyan is formed.

  As shown in FIG. 4, the image forming unit 18 includes a photoconductor 10, a charging device (160) that uniformly charges the photoconductor 10, and an exposure device 21 for each image based on each image information. A developing device that develops an electrostatic latent image formed by exposing the photoreceptor 10 with each toner (black toner, yellow toner, magenta toner, and cyan toner) to form a visible image with each toner. (61) includes a transfer charger (62) for transferring a visible image onto the intermediate transfer member 50, a cleaning device (63), and a charge eliminating device (64). A visible image can be formed. Next, the visible images of the respective colors are sequentially transferred (primary transfer) onto the intermediate transfer body 50 that is rotated and moved by the support rollers 14, 15 and 16, and the visible images of the respective colors are superimposed to form a composite transfer image. It is formed.

  On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed the recording paper from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and one sheet at a time by the separation roller 145. The paper is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 to stop. Alternatively, the paper feed roller 142 is rotated to feed out the recording paper on the manual feed tray 54, separated one by one by the separation roller 52, put into the manual paper feed path 53, and abutted against the registration roller 49 and stopped. The registration roller 49 is generally used while being grounded, but may be used in a state where a bias is applied to remove paper dust from the recording paper. Then, the registration roller 49 is rotated in synchronization with the composite transfer image formed on the intermediate transfer member 50, and the recording paper is sent between the intermediate transfer member 50 and the secondary transfer device 22, so that the secondary transfer device. By transferring the composite transfer image onto the recording paper (secondary transfer) by 22, a color image is formed on the recording paper. The toner remaining on the intermediate transfer member 50 is removed by the cleaning device 17.

  The recording paper on which the color image is formed is conveyed by the secondary transfer device 22 and sent to the fixing device 25, where the composite transfer image is heated and pressed and fixed on the recording paper. Thereafter, the recording paper is switched by the switching claw 55 and discharged by the discharge roller 56 and is stacked on the discharge tray 57. Alternatively, it is switched by the switching claw 55 and reversed by the reversing device 28 and led to the transfer position again. After an image is formed also on the back surface, the sheet is discharged by the discharge roller 56 and stacked on the discharge tray 57.

  According to the image forming method of the present invention, an image forming toner that has excellent low-temperature fixability and heat-resistant storage stability even at high speed and is fixed only at a desired position on a recording medium without causing an offset phenomenon is used. Therefore, even when an image is formed by an electrophotographic image forming apparatus having a high output speed, it is excellent in glossiness, and it is possible to stably output a high-quality image without generating a ghost or the like.

(Image forming device)
The image forming apparatus of the present invention includes at least an image carrier, a charging unit that charges the surface of the image carrier, and an exposure unit that exposes the charged image carrier surface to form an electrostatic latent image. Developing means for developing the electrostatic latent image using an image forming toner to form a visible image; and transfer means for transferring the developed toner image onto a recording medium to form an unfixed image; And an image forming apparatus provided with a fixing means for fixing the unfixed image to the recording medium, wherein the image forming toner used for forming the visible image is the image forming toner described above. It is characterized by being.

According to the image forming apparatus of the present invention, an image forming toner that has excellent low-temperature fixability and heat-resistant storage stability even at a high speed and is fixed only at a desired position on a recording medium without causing an offset phenomenon is used. Therefore, even if the process line speed is high, an abnormal image is not generated and the image can be fixed stably. For example, if a tandem full-color image forming apparatus is used, a higher-quality image can be output at a higher speed. The image forming method and the image forming apparatus of the present invention can be widely applied to electrophotographic application fields using electrophotography (for example, electrostatic copying machines, laser beam printers, etc.).
In addition, since the above-described tandem image forming apparatus can transfer a plurality of toner images at a time, high-speed full-color printing is realized.

The image forming means as described above may be fixedly incorporated in the copying apparatus, facsimile, or printer, but may be incorporated in these apparatuses in the form of a process cartridge.
The process cartridge is an apparatus (part) that contains an image carrier (photoconductor) and further includes a means selected from a charging unit, an exposure unit, a developing unit, a transfer unit, and a cleaning unit. If necessary, other means such as a static elimination means may be included. There are many shapes and the like of the process cartridge, but general examples include those shown in the figure. Here, the process cartridge includes a photosensitive member (101), and includes a charging unit (102), an exposure unit (103), a developing unit (104), and a cleaning unit (107). It has the means of. In the figure, reference numeral 105 denotes a recording medium (transfer body), and 106 denotes transfer means.

  That is, the process cartridge of the present invention includes an image carrier, a charging unit that charges the surface of the image carrier, an exposure unit that exposes the charged image carrier surface to form an electrostatic latent image, and a formed static member. It is selected from developing means for developing the electrostatic latent image using image forming toner, transfer means for transferring the developed toner image to the recording medium, and cleaning means for removing the toner remaining on the surface of the image carrier after the transfer. A process cartridge that can be attached to and detached from an image forming apparatus main body integrated with at least one means, and has the developing means, and the image forming toner to be used is the image forming toner of the present invention. It is characterized by being. It should be noted that other means (for example, static elimination means) may be included as necessary as at least one means to be selected.

  In the process cartridge of the present invention, since the image forming toner of the present invention is supplied from the developing unit, the fixing unit is stably fixed only at a desired position on the recording medium without causing an offset phenomenon due to an unfixed image. High quality images can be output. In addition, it is easy to store and transport and has excellent handling properties.

Examples and comparative examples are shown below. In addition, a part represents a weight part.
(Pigment hydrophilicity test)
When the hydrophilicity of PR81 (manufactured by Daido Kasei Co., Ltd.), PR57: 1 (manufactured by Toyo Ink Co., Ltd.) and PY180 (manufactured by Clariant) used in Examples and Comparative Examples was examined, all were judged to be hydrophilic.

[Examples 1 to 9]
Examples of the present invention are shown below. The surface treatment and surface treatment emulsifiers in the examples are summarized in Table 1, and the evaluation results obtained as toners are summarized in Table 2.

(Surface treatment, pigments 1-9)
Rhodamine pigments (PR81, manufactured by Daido Kasei Co., Ltd.), carmine pigments (PR57: 1, manufactured by Daido Kasei Co., Ltd.), yellow pigments (PY180, manufactured by Clariant), and triglyceryl pentastearate (Sakamoto) as emulsifiers. Table 1 using Yakuhin Kogyo Co., Ltd., HLB = 3), sucrose stearate (S-070, Mitsubishi Chemical Foods Co., Ltd., HLB = 3) and zirconia beads (3 mmφ, Nikkato Co., Ltd.) Stirring was carried out for 15 hours with a paint shaker (manufactured by Asada Tekko Co., Ltd.) at the prescribed amount as shown, and surface treatment was performed to obtain [Pigments 1-9].

(Manufacture of toners 1-9)
(Synthesis of organic fine particle emulsion)
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [fine particle dispersion 1] was obtained. The average particle diameter of the [fine particle dispersion 1] measured by LA-920 (Laser diffraction / scattering particle size distribution measuring device manufactured by Horiba, Ltd.) was 105 nm. A portion of [Fine Particle Dispersion 1] was dried to isolate the resin component. The weight average molecular weight of this resin was 150,000.

(Preparation of aqueous phase)
990 parts of water, 99 parts of [fine particle dispersion 1], 35 parts of a 48.5% aqueous solution of dodecyl diphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries) and 70 parts of ethyl acetate were mixed and stirred. A liquid was obtained. This is designated [Aqueous Phase 1].

(Synthesis of polyester resin 1)
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts terephthalic acid, 46 parts adipic acid and dibutyl 2 parts of tin oxide was added, reacted at 230 ° C. for 8 hours at normal pressure, and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg. Then 44 parts of trimellitic anhydride was added to the reaction vessel, and 1 part at 180 ° C. and normal pressure. For 8 hours to obtain [Polyester Resin 1]. [Polyester resin 1] had a number average molecular weight of 2500, a weight average molecular weight of 6700, and a peak molecular weight of 5000.

(Synthesis of intermediate polyester)
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, trimellitic anhydride 22 And 2 parts of dibutyltin oxide were added, reacted at 230 ° C. for 8 hours at normal pressure, and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg to obtain [Intermediate Polyester 1]. [Intermediate Polyester 1] had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, Tg of 55 ° C., an acid value of 0.5, and a hydroxyl value of 51.

(Synthesis of Prepolymer 1)
Next, 410 parts of [Intermediate polyester 1], 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. Polymer 1] was obtained.

(Synthesis of ketimine)
In a reaction vessel equipped with a stirrer and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain [ketimine compound 1].

(Production of oil phase)
After charging 160 parts of [Polyester resin 1], 32 parts of carnauba wax, and 400 parts of ethyl acetate in a container equipped with a stirring bar and a thermometer, the temperature was raised to 80 ° C. with stirring, and maintained at 80 ° C. for 5 hours. Cooled to 30 ° C. in 1 hour. Next, after adding [Pigment 1-9] to the container so as to be 15 parts with respect to 100 parts of [Polyester resin 1], 40 parts of ethyl acetate was charged and mixed for 1 hour [raw material solution 1 with a solid content of 50 wt% To 9].
[Material solution 1-9] 464 parts were transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feed speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads were 80. The pigment and WAX were dispersed under the conditions of volume% filling and 3 passes. Next, 420 parts of a 50% ethyl acetate solution of [Polyester Resin 1] was added, followed by one pass with a bead mill under the above conditions to obtain [Pigment / WAX Dispersions 1-9].

(Emulsification ⇒ Solvent removal)
[Pigment / WAX dispersions 1-9] 885 parts, [Prepolymer 1] 115 parts, [Ketimine compound 1] 2.9 parts in a container, 1 at 5000 rpm with a TK homomixer (manufactured by Koki Co., Ltd.) After mixing for 1 minute, 1200 parts of [Aqueous Phase 1] was added to the container, and mixed with a TK homomixer at a rotational speed of 12500 rpm for 30 minutes to obtain [Emulsified Slurries 1-9].
[Emulsified slurry 1-9] is put into a container in which a stirrer and a thermometer are set, and after removing the solvent at 35 ° C. for 7 hours, aging is performed at 45 ° C. for 4 hours to obtain [dispersed slurry 1-9]. It was. In the middle of solvent removal, the sample was transferred to a TK homomixer and stirred at a rotational speed of 12,500 rpm for 40 minutes to deform the toner.
Here, several g of the supernatant liquid [supernatant liquids 1-9] of [dispersed slurries 1-9] after aging was weighed and used as a supernatant liquid for inspection of elution into an aqueous medium.

(Washing ⇒ drying)
[Dispersion Slurries 1-9] After filtering 100 parts under reduced pressure,
(1): 100 parts 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): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(4): 300 parts of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered twice to obtain [filter cakes 1 to 9]. It was.

(Preparation of base toner)
[Filtered cakes 1 to 9] were dried at 45 ° C. for 48 hours in a circulating drier, sieved with an opening of 75 μm mesh, and a charge control agent (salicylic acid metal salt E−) was added to 100 parts of the obtained particles. 84: Orient Chemical Industry Co., Ltd.) 0.6 parts were mixed at 1000 rpm using a Henschel mixer, and then mixed at 5500 rpm with a Q-type mixer (Mitsui Metal Industries Co., Ltd.) to fix the charge control agent on the toner surface. [Base toners 1 to 9] were obtained.

(Addition of external additives)
Next, 100 parts of [base toner 1 to 9] was mixed with 0.7 part of hydrophobic titanium oxide using a Henschel mixer to complete the production of [toner 1 to 9].

(Inspection of elution into aqueous media)
[Supernatant liquids 1 to 9], which is an aqueous solvent after granulation, are poured into a predetermined quartz cell having a layer thickness of 1 cm so that the height is about 70%, and V-650DS manufactured by JASCO Corporation. The transmittance at a spectral wavelength of 700 nm to 400 nm was measured at a scanning speed of 2 nm / sec. At this time, since the rhodamine pigment is a magenta colorant, the transmittance of 550 nm was measured, and the yellow pigment was measured to have a transmittance of 450 nm.

(Image inspection)
[Toner 1 to 9] obtained by the above method is mixed with the carrier used in imageoMP C4300 (manufactured by Ricoh) so that the toner concentration is 5%, and the developer weight is added to the magenta unit of the image forming apparatus. The amount was added so as to be 180 g.
Using this developer, a monochrome image with an area ratio of 20% is output on A4 size paper (T6000 70W T, manufactured by Ricoh) so that the toner amount is 0.45 mg / cm ^2, and the fixed image is X -Status A mode of Rite 938 (manufactured by X-Rite), measure chromaticity a * b * with d50 light, and calculate saturation c * from the square root of the sum of the squares of a * and b * It was.

(Toner pass / fail judgment)
From the evaluation results of the transmittance and the saturation c *, the toner pass / fail judgment was performed as follows.
A: The transmittance is 80% or more and the chroma c * is 80 or more. O: The transmittance is 80% or more and the chroma c * is 70 or more and less than 80. X: The transmittance is less than 80%. , And / or chroma c * is less than 70 If the transmittance at a wavelength of 550 nm (magenta) and 450 nm (yellow) is 80% or more and the chroma c * is 70 or more in the elution test in an aqueous medium Passed.

[Comparative Example 1]
[Pigment 10] was obtained in the same manner as in Example 1 except that a rhodamine pigment (PR81, manufactured by Daido Kasei Co., Ltd.) was used as the pigment without surface treatment with an emulsifier.
[Toner 10] was granulated in the same manner except that [Pigment 1] used in Example 1 was changed to [Pigment 10], and the evaluation was performed in the same manner.

Evaluation Results From the above results, [Toner 1] to [Toner 9] produced in Examples 1 to 9 were judged as acceptable (（, ○), but [Toner 10] produced in Comparative Example 1 was In addition, the elution into the aqueous medium and the saturation could not satisfy the standard, and it was judged as rejected (x). From the above, it was shown that the present invention is effective.

(About FIGS. 1-4)
10 Image carrier (photoreceptor)
10K black image carrier 10Y yellow image carrier 10M magenta image carrier 10C cyan image carrier 14 support roller 15 support roller 16 support roller 17 intermediate transfer cleaning device 18 image forming unit 20 charging device (charging roller)
21 Exposure device 22 Secondary transfer device 23 Support roller 24 Secondary transfer belt 25 Fixing device 26 Fixing belt 27 Pressure roller 28 Reversing device 30 Exposure device 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading sensor 40 Developing device 41 Developing belt 42K Developer container 42Y Developer container 42M Developer container 42C Developer container 43K Developer supply roller 43Y Developer supply roller 43M Developer supply roller 43C Developer supply roller 44K Developer Roller 44Y Development roller 44M Development roller 44C Development roller 45K Black development unit 45Y Yellow development unit 45M Magenta development unit 45C Cyan development unit 49 Registration roller 50 Intermediate transfer member 51 Support roller 52 Separation roller 53 Manual feed path 54 Manual feed Lay 55 Switching claw 56 Ejection roller 57 Ejection tray 58 Corona charger 60 Cleaning device 61 Development device 62 Transfer charger 63 Photoconductor cleaning device 64 Electrostatic discharge device 70 Electric discharge device 80 Transfer device 90 Cleaning device 95 Transfer object 100A, 100B, 100C Image forming apparatus 120 Image forming means 130 Document base 142 Paper feed roller 143 Paper bank 144 Paper feed cassette 145 Separating roller 146 Paper feed path 147 Transport roller 148 Paper feed path 150 Copying apparatus main body 160 Charging apparatus 200 Paper feed table 300 Scanner 400 Document Automatic transfer device (ADF)

(About Figure 5)
DESCRIPTION OF SYMBOLS 101 Photoconductor 102 Charging means 103 Exposure means 104 Developing means 105 Recording medium 106 Transfer means 107 Cleaning means

Japanese Patent No. 4169943 Japanese Patent No. 4299084 Japanese Patent No. 2584450

Claims (11)

A toner obtained by dispersing and granulating an oil phase containing at least a binder resin and a colorant in an aqueous medium,
The image forming toner according to claim 1, wherein the colorant is obtained by surface-treating a hydrophilic colorant in an organic solvent with an emulsifier obtained by an ester reaction of a polyhydric alcohol and a monovalent fatty acid.   The image forming toner according to claim 1, wherein the hydrophilic colorant is a pigment obtained by rakeizing a dye.   The image forming toner according to claim 1, wherein the hydrophilic colorant is a pigment obtained by lake conversion of a rhodamine dye.   The image-forming toner according to claim 1, wherein the emulsifier is obtained by an ester reaction between glycerin and stearic acid.   The image forming toner according to claim 1, wherein the surface treatment with the emulsifier is performed in an amount of 10 to 100 parts by weight of the emulsifier with respect to 100 parts by weight of the hydrophilic colorant.   A two-component developer comprising the image forming toner according to claim 1 and a carrier.   A charging step for charging at least the surface of the image carrier, an electrostatic latent image forming step for forming an electrostatic latent image on the image carrier, and developing the electrostatic latent image with toner to form a visible image An image forming method comprising: a developing step, a transfer step of transferring the visible image onto a recording medium to form an unfixed image, and a fixing step of fixing the unfixed image on the recording medium, An image forming method, wherein the toner used to form the visible image is the image forming toner according to claim 1.   The image forming method according to claim 7, wherein a conveyance speed of the recording medium in the fixing step is 280 mm / second or more.   At least an image carrier, a charging unit that charges the surface of the image carrier, an exposure unit that exposes the charged image carrier surface to form an electrostatic latent image, and the electrostatic latent image using toner Developing means for forming a visible image by developing, transfer means for transferring the developed toner image onto a recording medium to form an unfixed image, and fixing means for fixing the unfixed image to the recording medium An image forming apparatus comprising: the image forming apparatus according to claim 1, wherein the toner used for forming the visible image is the image forming toner according to claim 1. .   The image forming apparatus according to claim 9, wherein a conveyance speed of the recording medium at the time of fixing by the fixing unit is 280 mm / second or more.   An image carrier, a charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged surface of the image carrier to form an electrostatic latent image, and the formed electrostatic latent image using toner At least one means selected from a developing means for developing, a transferring means for transferring the developed toner image to a recording medium, and a cleaning means for removing toner remaining on the surface of the image carrier after transfer is integrated with the image. 6. A process cartridge that is detachable from a main body of the forming apparatus, further comprising developing means for developing the formed electrostatic latent image using toner, wherein the toner used is any one of claims 1 to 5. A process cartridge, which is the image forming toner according to claim 1.

Images