JP2007079344A - Manufacturing method for toner for electrostatically charged image development - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for toner in which toner having an invariably stable volume mean particle size and a sharp particle size distribution is easily manufactured without waste, the toner being suitable to a fixing device capable of saving energy, having excellent developing property for a long period, and forming an image of high image quality. <P>SOLUTION: Disclosed is the manufacturing method for the toner including an emulsifying and dispersing stage of obtaining emulsified liquid by mixing an organic solvent composition containing a binder resin and a coloring agent at least in an organic solvent with a water type medium and applying shearing force to the mixed liquid, the manufacturing method for toner for electrostatically charged image developer being characterized in that the volume mean particle size of toner particles present in the emulsified liquid obtained when the weight ratio of the organic solvent composition and water type medium in the mixed liquid is varied within a range of 60:40 to 20:80 is measured and the emulsifying and dispersing stage is carried out within a range of the weight ratio [%] of the organic solvent composition such that the relation between the weight ratio [%] of the organic solvent composition to all the mixed liquid and the volume mean particle size under fixed shearing force conditions is -6.0 to +6.0 (μm/%). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a toner for developing an electrostatic image that visualizes an electrostatic image formed on the surface of a latent image carrier such as a photoreceptor in electrophotography or electrostatic recording.

  In recent years, the market demanded smaller particle size for higher image quality and low-temperature fixing for energy saving. In particular, image formation is possible after the image forming apparatus is ready for energy saving. In order to reduce as much as possible the amount of power required for the waiting time (warm-up time of the apparatus) until the time is reached, there is a strong demand for shortening the waiting time. However, the toner obtained by the usual kneading and pulverization method has various problems such as difficulty in reducing the particle size, irregular shape, broad particle size distribution, and high fixing energy. In particular, in the case of fixing, a kneading and pulverizing type toner prepared by a pulverization method has a large amount on the surface because pulverization is broken at the interface of the release agent (wax). Adhesion was likely to occur, and the performance was unsatisfactory.

  On the other hand, in order to overcome the above-mentioned problems caused by the kneading and pulverization method, a toner production method by a polymerization method has been actively proposed. This method makes it easy to reduce the particle size of the toner, and the particle size distribution is sharper than the particle size distribution of the toner obtained by the pulverization method. In addition, wax can be included. For example, Patent Document 1 and Patent Document 2 propose an emulsion polymerization aggregation method, and further, Patent Document 3 and Patent Document 4 describe techniques for improving the problems in the use of a surfactant possessed by the emulsion aggregation method. ing. However, the above-described toner production method using the emulsion aggregation method requires heating and melting at a temperature higher than the glass transition point of the binder resin for a long time to form toner particles from the aggregate, which requires a great deal of energy. There's a problem.

  According to Patent Document 5, a practical sphericity composed of an elongation reaction product of a urethane-modified polyester as a toner binder for the purpose of improving toner fluidity, low-temperature fixability, and hot offset property is 0.90. A dry toner of 1.00 has been proposed. Further, Patent Document 6, Patent Document 7 and the like are dry toners that are excellent in powder flowability and transferability in the case of a small particle size toner, and also excellent in all of heat-resistant storage stability, low-temperature fixability, and hot offset resistance. It is described in. The toner production methods described in these publications include a high molecular weight process in which an isocyanate group-containing polyester prepolymer is subjected to a polyaddition reaction with an amine in an organic solvent and an aqueous medium. However, the above-described method has problems such as difficulty in controlling fine powder generated when obtaining emulsified particles and coarsening of the emulsified particles over time due to shearing force, and stable and sharp particle size distribution. There is a problem that a toner having a particle diameter cannot be obtained.

Furthermore, Patent Document 8 discloses a technique of using a polymer dispersant having a total amine value of 1 to 100 in a method for producing a resin particle composition in which a colorant is dispersed in a resin. . According to this publication, excellent dispersion stability can be obtained by using a dispersant having an amine value. However, it is possible to obtain a sharp particle size distribution with few fine powders and process conditions such as shearing force. This technique is still insufficient for finely adjusting the particle size by changing.
Japanese Patent Laid-Open No. 63-282275 JP-A-6-250439 JP 2000-275907 A JP 2001-305797 A Japanese Patent Laid-Open No. 11-133665 JP 2002-287400 A JP 2002-351143 A JP 2002-194234 A

  SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention can easily and efficiently produce a toner having a stable volume average particle size and a sharp particle size distribution, thereby achieving energy saving. It is an object of the present invention to provide a method for producing a toner that can form a high-quality image with good developability over the long term.

  As a result of repeated extensive studies by the present inventors, an organic solvent composition containing at least a binder resin and a colorant in an organic solvent is mixed in an aqueous medium, and a shearing force is applied to the mixed solution, In the method for producing a toner for developing an electrostatic charge image having a step of obtaining an emulsion, the toner particles have a narrow particle size distribution, which is free from scattering and fogging, has long-term developability and high image quality. It came to the conclusion that it is indispensable to form. Therefore, the present inventors have different methods from the reduction of fine particles accompanied by an increase in productivity and cost, such as a yield loss typified by coarse powder / fine powder classification and an energy load increase typified by an emulsion aggregation method. Thus, the process conditions for realizing narrowing of the particle size distribution of the toner particles were sought.

As a result, the volume average particle size of the toner particles present in the emulsion obtained when the weight ratio of the organic solvent composition to the aqueous medium in the mixed solution is varied within the range of 60:40 to 20:80 is obtained. The range in which the relationship between the weight ratio [%] of the organic solvent composition to the total mixed solution under a constant shearing force condition and the volume average particle diameter is −6.0 to +6.0 (μm /%) In particular, it was found that a toner having a sharp particle size distribution with little coarse powder / fine powder can be manufactured easily and without waste by performing the emulsification dispersion step.
That is, the present invention is characterized by the following.

(1) It has an emulsification dispersion step of mixing an organic solvent composition containing at least a binder resin and a colorant in an organic solvent in an aqueous medium, and applying an shearing force to the mixture to obtain an emulsion. A method for producing a toner, wherein the toner particles present in the emulsion obtained when the weight ratio of the organic solvent composition to the aqueous medium in the mixed solution is varied within the range of 60:40 to 20:80. The volume average particle diameter was measured, and the relationship between the weight ratio [%] of the organic solvent composition to the total mixture under a constant shearing force condition and the volume average particle diameter was −6.0 to +6.0 (μm / %), The emulsion dispersion step is carried out within the range of the weight ratio [%] of the organic solvent composition.

(2) The emulsification and dispersion step is a step of obtaining an emulsion by applying a shear force while continuously supplying the organic solvent composition and the aqueous medium to the disperser or the emulsifier, under a constant shear force condition. In the above (1), the relationship between the weight ratio [%] of the organic solvent composition to the total liquid mixture and the volume average particle diameter is −1.5 to +3.0 (μm /%). A method for producing the toner for developing an electrostatic image according to claim 1.

(3) In the method for producing an electrostatic charge image developing toner according to (1) or (2), wherein at least the binder resin in the organic solvent composition contains a polyester resin. is there.
(4) In the production method, the total amine value of the organic solvent composition is 1.0 to 10.0 (KOH mg / g), and the total amine value of the organic solvent composition is 0.20 to 0.40 (KOH mg). / G) The volume average particle diameter of the toner particles present in the emulsion obtained when it is varied within each range is measured, and the minimum two when the relationship between the total amine value and the volume average particle diameter is linearly approximated. The emulsification and dispersion step is performed within a range where the correlation coefficient (R2) obtained by multiplication is 0.9 or more and the slope of the approximate expression is −0.2 to −8. The method for producing a toner for developing an electrostatic charge image according to any one of 1) to (3).

(5) The toner for developing an electrostatic charge image according to any one of (1) to (4), wherein the organic solvent composition has an acid value of 2 to 30 KOHmg / g in the production method. It is a manufacturing method.
(6) In the above-mentioned production method, the organic solvent composition is obtained by dissolving or dispersing a polymer having a site capable of reacting with a compound having an active hydrogen group in at least an organic solvent, and a coloring agent. The method further comprises a step of reacting a polymer having a site capable of reacting with the compound having an active hydrogen group while dispersing or dispersing the composition in an aqueous medium by mechanical shearing force. 1) A method for producing a toner for developing an electrostatic charge image according to any one of (5).

(7) In the manufacturing method, the volume average particle diameter of the toner particles present in the obtained emulsion is 3 to 8 μm, according to any one of (1) to (6), This is a method for producing a toner for developing an electrostatic image.
(8) In the above production method, after the toner emulsification dispersion step, an organic solvent removal step is performed, and the volume average particle diameter and number average particle size of the toner particles present in the obtained toner particle dispersion liquid after removal of the organic solvent are obtained. The method for producing a toner for developing an electrostatic charge image according to any one of (1) to (7), wherein a ratio of diameters (Dv / Dn) is 1.20 or less.
(9) In the above production method, the toner particles present in the resulting emulsion have an average circularity of 0.92 to 1.00, any one of (1) to (8) above The method for producing a toner for developing an electrostatic image described in 1.

(10) An electrostatic image developing toner produced by using the method for producing an electrostatic image developing toner according to any one of (1) to (9).
(11) A developer comprising the electrostatic image developing toner according to (10).
(12) An electrostatic image developing toner-containing container, wherein the electrostatic image developing toner according to (10) is accommodated in a container.
(13) An image forming apparatus using the electrostatic image developing toner according to (10).
(14) In a process cartridge which integrally supports a latent image carrier and at least one unit selected from a charging unit, a developing unit, and a cleaning unit and is detachable from the main body of the image forming apparatus, the developing unit is an electrostatic image. A process cartridge for holding a developing toner, wherein the electrostatic image developing toner is the electrostatic image developing toner according to (10).

  According to the present invention, a toner having a stable volume average particle diameter and a sharp particle size distribution can be produced easily and without waste. As a result, the toner is suitable for a fixing device that can achieve energy saving and has long-term developability. A toner manufacturing method capable of forming a good and high-quality image can be provided.

The present invention is described in detail below.
According to the study of the present invention, the weight ratio of the organic solvent composition to the aqueous medium is 60:40 to 20:80. When the weight ratio of the organic solvent composition in the mixed liquid exceeds 60%, the emulsification becomes unstable, and there is a possibility that aqueous medium particles are formed in the organic solvent composition (W / O). is there. If the weight ratio of the organic solvent composition in the mixed liquid is less than 20%, emulsification may become unstable depending on the organic solvent composition, and the yield is low, which is a problem in production.

Even if it is manufactured using the same kind of raw materials due to changes in the composition of lots of naturally-derived raw materials (wax, etc.) used for toners or changes in equipment conditions due to continuous operation of equipment, The particle size may be slightly different. At that time, it is effective to change the weight ratio of the organic solvent composition to the aqueous medium in the mixed solution as a method for obtaining toner particles having the required particle size without adjusting the formulation of the organic solvent composition and the aqueous medium. I found out.
In granulation by mixing / dispersing the organic solvent composition and the aqueous medium, the particle diameter varies depending on the weight ratio of the organic solvent composition and the aqueous medium in the mixed solution. The relationship between the weight ratio [%] of the organic solvent composition to the total mixed solution under a constant shearing force condition and the volume average particle diameter is as shown in FIG. There are two levels of the weight ratio of the organic solvent composition capable of obtaining an arbitrary particle size, and it is preferable to control at a portion where the weight ratio of the organic solvent composition is large in view of the yield. At this time, the relationship between the weight ratio [%] of the organic solvent composition to the total mixed solution under a constant shearing force condition and the volume average particle diameter is −6.0 to +6.0 (μm /%). It is necessary to be in the range. Outside this range, the change in particle size becomes large due to the measurement blurring of the organic solvent composition and the aqueous medium (the fluctuation of the flow rate when continuously dispersed). Preferably, it is in the range of −1.5 to +3.0 (μm /%). -1.5 to +3.0 (μm /%), the volume average particle size is gradually changed with respect to the weight ratio of the organic solvent composition, the particle size can be easily controlled, and a desired particle size distribution is desired. A toner having a particle size can be obtained. Moreover, in the method of producing an emulsion by applying a shearing force while continuously supplying an organic solvent composition and an aqueous medium to a disperser or an emulsifier, a large amount of the emulsion is produced regardless of the production scale. If the initial emulsion does not have the desired particle size, it can be sharpened without stopping the emulsifier by adjusting the flow rate of the organic solvent composition and aqueous medium to the emulsifier. An emulsion containing particles having a desired particle size having a particle size distribution can be produced.

  The average particle size and particle size distribution of the toner particles present in the emulsified liquid of the present invention are an interface (manufactured by Nikka Giken Co., Ltd.) that outputs a number distribution and a volume distribution using a Coulter Counter TA-II type, and a PC 9801 personal computer. (NEC) was connected and measured.

  Considering the above, it becomes possible to stably and easily produce a toner having a sharp particle size distribution with less coarse / fine powder.

  Furthermore, the binder resin in the organic solvent composition of the present invention preferably contains a polyester resin. The polyester resin is easy to reduce the molecular weight and excellent in low-temperature fixability as compared with the styrene acrylic resin, and is a preferable material for energy saving.

  Further, the total amine value of the organic solvent composition is 1.0 to 10.0 (KOH mg / g), and the total amine value of the organic solvent composition is 0.20 to 0.40 (KOH mg / g). The volume average particle diameter of the toner particles present in the emulsion obtained when it was varied within the range of γ was measured, and obtained by the least square method when the relationship between the total amine value and the volume average particle diameter was linearly approximated It is desirable to perform the emulsification dispersion step within a range where the correlation coefficient (R2) is 0.9 or more and the slope of the approximate expression is −0.2 to −8. Giving the total amine value is necessary to control the system stability during emulsification and the particle size of the emulsified particles, and if it is less than 1 KOHmg / g, the system tends to become very unstable and stable emulsification is difficult. Become. In addition, if it exceeds 10 KOHmg / g, the inside of the system is too stable, so that the slope of the approximate expression is likely to be flat, and it is difficult to control the target particle diameter. When the correlation coefficient (R2) is less than 0.9, or when the slope of the approximate expression is less than −8, the toner particle diameter varies greatly due to slight touch when preparing the organic solvent composition. Therefore, a stable and uniform emulsion dispersion cannot be obtained. In addition, when the slope of the approximate expression is flatter than −0.2, it is possible to obtain a uniform emulsified dispersion, but since the system is too stable, it is difficult to remove the generated fine powder by coalescence, Fine adjustment to the target particle size by changing process conditions such as shear force is extremely difficult. The method for measuring the amine value and acid value of the present invention is based on a method based on JIS K0070. However, when the sample does not dissolve, a solvent such as dioxane or THF is used as the solvent.

  Moreover, it is preferable that the acid value in the organic-solvent composition of this invention is the range of 2-30 (KOHmg / g). The provision of an acid value is advantageous for improving the adhesion of toner to paper, and an acid value of 2 KOHmg / g or more is required. However, when the acid value is higher than 30 KOHmg / g, the stability in the system at the time of emulsification increases and the coalescence of fine particles does not progress, so that it is difficult to obtain a toner having a sharp particle size distribution.

  In addition, since it is difficult to dissolve or disperse the polymer component in which the reaction is completed in the organic solvent, in the present invention, the polymer component necessary for developing the offset resistance is uniformly distributed in the particles. In order to introduce the organic solvent composition, at least a polymer having a site capable of reacting with a compound having an active hydrogen group and a colorant are dissolved or dispersed in the organic solvent. It is preferable to have a step of reacting a polymer having a site capable of reacting with the compound having an active hydrogen group while being dispersed in an aqueous medium by a shearing force or while being dispersed.

  The toner particles present in the emulsion obtained by the production method of the present invention preferably have a volume average particle diameter of 3 to 8 μm, and the toner particles present in the toner particle dispersion after removal of the organic solvent. The ratio of the volume average particle diameter to the number average particle diameter (Dv / Dn) is preferably 1.20 or less. By defining Dv / Dn in this way, it is possible to obtain a toner with high resolution and high image quality. In order to obtain a higher quality image, the volume average particle diameter of the toner is 3 to 7 μm, the ratio (Dv / Dn) to the number average particle diameter is Dv / Dn of 1.17 or less, and 4 μm or less. The number average particle size is preferably 1 to 10% by number, and more preferably, the volume average particle size is 4 to 7 μm and Dv / Dn is 1.15 or less. Such a toner, when used in a full-color copying machine or the like, is free from scattering and fogging, and can form a high-quality image with good developability over the long term.

  The toner particles present in the emulsion obtained by the production method of the present invention preferably have a specific shape and shape distribution. If the average circularity is less than 0.92, the coalescence of fine particles is insufficient. Therefore, it is difficult to obtain a satisfactory transferability and a high-quality image free from dust. As a method for measuring the shape, an optical detection band method is suitable in which a suspension containing particles is passed through an imaging unit detection band on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. Toner having an average circularity of 0.92 to 1.00, which is a value obtained by dividing the perimeter of an equivalent circle having the same projected area obtained by this method by the perimeter of the actual particle, has high reproducibility with an appropriate density reproducibility. It is preferable for forming a clear image. The average circularity of the toner particles present in the emulsion of the present invention can be measured by a flow type particle image analyzer FPIA-2000 (manufactured by Toa Medical Electronics Co., Ltd.). As a specific measuring method, 0.1 to 0.5 ml of a surfactant, preferably alkylbenzene sulfonate is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance, and further measurement is performed. Add about 0.1-0.5g of sample. The suspension in which the sample is dispersed is obtained by performing dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and measuring the shape and distribution of the toner with the above apparatus at a dispersion concentration of 3000 to 10,000 / μl. .

The materials used for the toner of the present invention will be described in detail.
(Binder resin)
The binder resin that can be used in the present invention is a polymer of styrene such as polystyrene, poly-p-chlorostyrene, or polyvinyltoluene, and a substituted product thereof; styrene-p-chlorostyrene copolymer, styrene-propylene copolymer. Styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer Polymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene -Vinyl methyl ketone copolymer, styrene-butyl Styrene copolymers such as diene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer; polymethyl methacrylate, poly Butyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic Aromatic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be used, and these can be used alone or in combination, but polyester resins are preferred.

  The polyester resin that can be used in the present invention is usually obtained by condensation polymerization of alcohol and carboxylic acid. Examples of the alcohol include glycols such as ethylene glycol, diethylene glycol, triethylene glycol and propylene glycol, etherified bisphenols such as 1.4-bis (hydroxymethyl) cyclohexane and bisphenol A, and other dihydric alcohols. Mention may be made of monomers and trihydric or higher polyhydric alcohol monomers. Examples of carboxylic acids include divalent organic acid monomers such as maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, and malonic acid, 1,2,4-benzenetricarboxylic acid, 1 , 2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxy Mention may be made of trivalent or higher polyvalent carboxylic acid monomers such as propane and 1,2,7,8-octanetetracarboxylic acid.

(High molecular weight using prepolymer)
Further, the organic solvent composition is obtained by dissolving or dispersing a polymer having at least a site capable of reacting with a compound having an active hydrogen group and a colorant in the organic solvent, and the organic solvent composition is dissolved in an aqueous medium. It is preferable to have a step of reacting a polymer having a site capable of reacting with the compound having an active hydrogen group while being dispersed by mechanical shearing force or while being dispersed. As the polymer having a site capable of reacting with a compound having an active hydrogen group, an isocyanate group-containing polyester prepolymer (A) is preferable. The compound having an active hydrogen group to be reacted with a polymer having a reactive site with a compound having an active hydrogen group is preferably an amine (B).

  The prepolymer that can be used in the present invention is preferably a polyester-based prepolymer (A) containing an isocyanate group, and is a polycondensate of a polyol (PO) and a polycarboxylic acid (PC) and a polyester having an active hydrogen group. Further, it can be obtained by reacting with polyisocyanate (PIC). In this case, examples of the active hydrogen group of the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable.

  Examples of the polyol (PO) include diol (DIO) and trivalent or higher polyol (TO), and (DIO) alone or a mixture of (DIO) and a small amount of (TO) is preferable. Diol (DIO) includes alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol, triethylene glycol, Ethylene 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 phenol compound (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. Trivalent or higher polyols (TO) include 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trivalent or higher phenols (Tris) Phenol PA, phenol novolak, cresol novolak, etc.); alkylene oxide adducts of the above trivalent or more polyphenols.

  Examples of the polycarboxylic acid (PC) include dicarboxylic acid (DIC) and trivalent or higher polycarboxylic acid (TC), and (DIC) alone and a mixture of (DIC) and a small amount of (TC) are preferable. Dicarboxylic 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, naphthalene) Dicarboxylic acid and the like). 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 polycarboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polycarboxylic acid (PC), you may make it react with a polyol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

  The ratio of the polyol (PO) and the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably 1 as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. 5/1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  Examples of the polyisocyanate (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.); isocyanurates; the polyisocyanates are phenol derivatives, oximes, caprolactams And a combination of two or more of these.

  When obtaining a polyester-based prepolymer having an isocyanate group, the ratio of the polyisocyanate (PIC) to the polyester-based resin (PE) having active hydrogen is such that the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group are The equivalent ratio [NCO] / [OH] is usually 5/1 to 1/1, preferably 4/1 to 1.2 / 1, and more preferably 2.5 / 1 to 1.5 / 1. The content of the polyisocyanate (PIC) component in the prepolymer A having an isocyanate group at the terminal is usually 0.5 to 40% by weight, preferably 1 to 30% by weight, more preferably 2 to 20% by weight. .

  As the amine (B), polyamines and / or amines having an active hydrogen-containing group are used. In this case, the active hydrogen-containing group includes a hydroxyl group and a mercapto group. Such amines include diamine (B1), tri- or higher polyamine (B2), aminoalcohol (B3), aminomercaptan (B4), amino acid (B5), and amino acids B1-B5 blocked ( B6) and the like. Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, Isophorone diamine etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine 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. Examples of the B1 to B5 amino group blocked (B6) include ketimine compounds and oxazoline compounds obtained from the B1 to B5 amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines B, (B1) and a mixture of (B1) and a small amount of (B2) are preferable.

  Furthermore, when making a prepolymer (A) and an amine (B) react, the molecular weight of polyester can be adjusted using an elongation terminator if necessary. Examples of the elongation terminator include monoamines having no active hydrogen-containing groups (diethylamine, dibutylamine, butylamine, laurylamine, and the like), and those blocked (ketimine compounds). The addition amount is appropriately selected in relation to the molecular weight desired for the urea-modified polyester to be produced.

  The ratio between the amine (B) and the prepolymer (A) having an isocyanate group is such that the isocyanate group [NCO] in the prepolymer (A) having an isocyanate group and the amino group [NHx] (x As an equivalent ratio [NCO] / [NHx] of usually 1 to 2, usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2. /1-1/1.2.

(Coloring agent)
As the colorant of the present invention, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher , Lead yellow, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Se Red, Para Chlorortonito Aniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmin Min BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R , Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolone red Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), indigo, ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Lid Russian nin green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 12% by weight, based on the toner.

  The colorant used in the present invention can also be used as a master batch combined with a resin. As the binder resin to be kneaded together with the production of the masterbatch or the masterbatch, in addition to the above-mentioned polyester resin, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and its substituted polymer; styrene-p-chloro Styrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-acrylic acid Butyl copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer Polymer, styrene-acryloni Ryl copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester Styrene copolymers such as copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid Resins, rosins, modified rosins, terpene resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be used, and these can be used alone or in combination.

  This master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force to obtain a master batch. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. Also, a so-called flushing method called watering paste containing water of a colorant is mixed and kneaded together with a resin and an organic solvent, and the colorant is transferred to the resin side to remove moisture and organic solvent components. Since it can be used as it is, it does not need to be dried and is preferably used. For mixing and kneading, a high shearing dispersion device such as a three-roll mill is preferably used.

(Charge control agent)
The toner of the present invention may contain a charge control agent as necessary. All known charge control agents can be used. For example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified) Quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine-based activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Nitronine-based dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E- 84, E-89 of phenol-based condensate (above, manufactured by Orient Chemical Industries), TP-302, TP-415 of quaternary ammonium salt molybdenum complex (above, manufactured by Hodogaya Chemical Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, 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), copper phthalocyanine, perylene, quinacridone Azo pigments, sulfonate group, carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

  In the present invention, the amount of charge control agent used is determined primarily by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is uniquely limited. Although it is not a thing, Preferably it is used in 0.1-10 weight part with respect to 100 weight part of binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the main charge control agent is reduced, the electrostatic attractive force with the developing roller is increased, the flowability of the developer is reduced, and the image density is reduced. Incurs a decline. These charge control agents can be dissolved and dispersed after being melt-kneaded with a masterbatch and resin, and of course, they can be added directly when dissolved and dispersed in an organic solvent, or fixed on the toner surface after preparation of toner particles. May be.

(External additive)
As the external additive for assisting the fluidity, developability and chargeability of the colored particles obtained in the present invention, inorganic fine particles can be preferably used. The primary particle diameter of the inorganic fine particles is preferably 5 mμ to 2 μm, and particularly preferably 5 mμ to 500 mμ. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The proportion of the inorganic fine particles used is preferably 0.01 to 5% by weight of the toner, and particularly preferably 0.01 to 2.0% by weight. 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, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.

  Other polymer fine particles such as polystyrene, methacrylic acid ester and acrylic acid ester copolymer obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization, polycondensation systems such as silicone, benzoguanamine, and nylon, and thermosetting resins Examples include polymer particles.

  Such a fluidizing agent 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. .

  Examples of the cleaning property improver for removing the developer after transfer remaining on the photoreceptor or the primary transfer medium include, for example, zinc stearate, calcium stearate, fatty acid metal salts such as stearic acid, such as polymethyl methacrylate fine particles, polystyrene fine particles, etc. And polymer fine particles produced by soap-free emulsion polymerization. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

Examples of the method for producing the toner for developing an electrostatic charge image of the present invention are illustrated below, but the present invention is not limited to these methods.
(Production of polyester resin)
Polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and water produced while reducing the pressure as necessary. Distill off to obtain a polyester resin.

(Prepolymer production)
Polyester having a hydroxyl group obtained by the same method as the above polyester resin is reacted with polyvalent isocyanate (PIC) at 40 to 140 ° C. to obtain a polyester prepolymer (A) having an isocyanate group. When reacting polyvalent isocyanate (PIC), a solvent can be used as necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.) that are inert to isocyanate compounds; ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (Dimethylformamide, dimethylacetamide and the like) and ethers (tetrahydrofuran and the like).

(Production of modified polyester resin)
The reaction between the polyester prepolymer (A) and the amines (B) may be carried out by mixing with other toner constituent materials, or may be prepared in advance. In the case of producing in advance, the polyester prepolymer (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a urea-modified polyester resin. Also in the case of reacting the polyester prepolymer (A) and the amines (B), a solvent can be used as necessary, as in the case of the prepolymer (A). Solvents that can be used are as described above.

(Toner production method in aqueous medium)
The aqueous medium used in the present invention may be water alone, or a solvent miscible with water may be used in combination. Examples of miscible solvents include alcohols (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (eg, methyl cellosolve), lower ketones (acetone, methyl ethyl ketone, etc.), and the like. The toner particles may be formed by reacting a dispersion composed of a polyester prepolymer (A) having an isocyanate group in an aqueous medium with amines (B), or using a modified polyester resin prepared in advance. good. As a method for stably forming a dispersion composed of a polyester resin or a polyester prepolymer (A) in an aqueous medium, a toner constituent material composed of a polyester resin or a polyester prepolymer (A) is added to the aqueous medium. However, other toner constituent materials such as wax and charge control agent may be mixed when the dispersion is formed in the aqueous medium, but after these toner constituent materials are mixed in advance. More preferably, the mixture is added and dispersed in an aqueous medium. In the present invention, toner constituent materials such as wax and charge control agent do not necessarily have to be mixed when forming particles in an aqueous medium, and may be added after the particles are formed. .

(Solid fine particle dispersant)
Further, by adding a solid fine particle dispersant in advance to the aqueous medium, the dispersion of oil droplets in the aqueous phase is made uniform. This is because the solid fine particle dispersant is arranged on the surface of the oil droplets at the time of dispersion, and the dispersion of the oil droplets is made uniform. Toner can be obtained. The solid fine particle dispersant is present in a solid state hardly soluble in water in an aqueous medium, and is preferably inorganic fine particles having an average particle diameter of 0.01 to 1 μm. Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. More preferably, tricalcium phosphate, calcium carbonate, colloidal titanium oxide, colloidal silica, hydroxyapatite and the like can also be used. In particular, hydroxyapatite synthesized by reacting sodium phosphate and calcium chloride in water under basic conditions is preferable.

  As a dispersant for emulsifying and dispersing the oil phase in which the toner composition is dispersed in an aqueous medium, anionic surfactants such as alkylbenzene sulfonate, α-olefin sulfonate, and phosphate ester, alkylamine salts, Amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, and quaternary alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride, etc. Nonionic surfactants such as ammonium salt type cationic surfactants, fatty acid amide derivatives, polyhydric alcohol derivatives such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N Amphoteric surfactants such as dimethyl ammonium betaine.

  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- [omega-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts thereof, 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-hydroxye B) Perfluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate Examples include esters.

  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 (Daikin Kogyo Co., Ltd.), Mega-Fac F-l0, F-l20, F-113, F-191, F-812, F-833 (Dainippon Ink Co., Ltd.), 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).

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

  Further, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloroacrylate 2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N -Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc., or esters of compounds containing vinyl alcohol and carboxyl groups, such as Vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, ethylene imine, etc. Homopolymers or copolymers such as those having a nitrogen atom or a heterocyclic ring thereof, polyoxyethylene, polyoxypropylene, Oxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonyl phenyl ester Polyoxyethylenes such as, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

  In addition, when an acid such as calcium phosphate salt or an alkali-soluble substance is used as the dispersion stabilizer, the calcium phosphate salt is dissolved from the fine 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.

  When a dispersant is used, the dispersant can remain on the surface of the toner particles. However, the dispersant is washed away after the elongation and / or crosslinking reaction between the polyester prepolymer (A) and the amine (B). This is preferable from the charged surface of the toner.

  The elongation and / or crosslinking reaction time is selected depending on the reactivity of 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. It is. 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.

  In order to remove the organic solvent from the obtained emulsified dispersion, a method in which the temperature of the entire system is gradually raised to completely evaporate and remove the organic solvent in the droplets can be employed. Alternatively, the emulsified dispersion can be sprayed into a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, and the aqueous dispersant can be removed by evaporation together. . As a dry atmosphere in which the emulsified dispersion is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, or the like, in particular, various air currents heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used is generally used. A spray dryer, belt dryer, rotary kiln, etc. can provide the desired quality in a short time.

  The resulting dried toner powder is mixed with different particles such as charge control agent, fluidizing agent, and colorant, or fixed and fused on the surface by applying mechanical impact force to the mixed powder. In addition, it is possible to prevent the detachment of the foreign particles from the surface of the obtained composite particle. Specific means include a method of applying an impact force to the mixture by blades rotating at high speed, a method of injecting and accelerating the mixture in a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) has been modified to reduce the pulverization air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, etc.

  Furthermore, the toner of the present invention can be used as a magnetic toner containing a magnetic substance. Examples of the magnetic material contained in the toner include iron oxides such as magnetite, hematite, and ferrite, metals such as iron, cobalt, and nickel, These metals include alloys of metals such as aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium, and mixtures thereof. Magnetite is particularly preferable from the viewpoint of magnetic properties. These ferromagnetic materials preferably have an average particle size of about 0.1 to 2 μm. The amount of the ferromagnetic material to be contained in the toner is about 15 to 200 parts by weight, particularly preferably 100 parts by weight of the resin component, with respect to 100 parts by weight of the resin component. 20 to 100 parts by weight per part.

  Since the toner of the present invention obtained as described above always has a stable volume average particle diameter and a sharp particle size distribution, it is suitable for a fixing device capable of achieving energy saving, and an image forming apparatus using the toner of the present invention is Thus, the image forming apparatus is capable of forming a high-quality image with good developability over the long term.

FIG. 2 shows a schematic configuration of a process cartridge having the electrostatic image developing toner of the present invention.
In the process cartridge, a latent image carrier 1, a charging unit 2, a developing unit 4, and a cleaning unit 5 are integrated. Among these, the toner of the present invention is incorporated in the developing means.

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto. Hereinafter, a part shows a weight part.

Production Example 1
(Example of polyester production)
690 parts of bisphenol A ethylene oxide 2-mole adduct and 335 parts of terephthalic acid are charged into a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, and condensed at 210 ° C. for 10 hours under a normal pressure nitrogen stream. Reacted. Next, the reaction was continued for 5 hours while dehydrating under reduced pressure of 10 to 15 mmHg, followed by cooling to obtain polyester (1). The obtained polyester resin had a weight average molecular weight of 6,000, an acid value of 10 KOH mg / g, and a glass transition point of 48 ° C.

Production Example 2
(Prepolymer production example)
Into a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introducing tube, 795 parts of bisphenol A ethylene oxide 2-mole adduct, 200 parts of isophthalic acid, 65 parts of terephthalic acid, and 2 parts of dibutyltin oxide were added at normal pressure. Under a nitrogen stream, condensation reaction was performed at 210 ° C. for 8 hours. Next, the reaction was continued for 5 hours while dehydrating under reduced pressure of 10 to 15 mmHg, then cooled to 80 ° C., and reacted with 170 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain a prepolymer. The obtained prepolymer had a weight average molecular weight of 5,000. Furthermore, the above-mentioned prepolymer solution was adjusted to 50% with ethyl acetate.

Production Example 3-1
(Production example of aqueous dispersion medium)
In a tank, 945 parts of water, 40 parts of a 20% aqueous dispersion of styrene-methacrylic acid-butyl acrylate copolymer, 160 parts of a 50% aqueous solution of sodium dodecyldiphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries), acetic acid 90 parts of ethyl was mixed and stirred to obtain an aqueous dispersion medium.

Production Example 4-1
(Production example of organic solvent composition)
Into the tank, 170 parts of 35% carnauba wax ethyl acetate dispersion, 120 parts of polyester (1), 3 parts of isophoronediamine, 20 parts of Pigment Yellow (PY155, Clariant) and 70 parts of ethyl acetate were added and stirred for 2 hours. And dissolved and mixed. Subsequently, the mixture was circulated and mixed for 1 hour using a high-efficiency disperser Ebara Milder (manufactured by Ebara Seisakusho).

Weight ratio (%) of organic solvent composition and volume average particle diameter Subsequently, 50% of the prepolymer and the organic solvent composition were mixed, and the liquid charged in the aqueous dispersion medium was stirred at 11000 rpm using a TK homomixer. The step of obtaining an emulsified liquid is carried out at a ratio of 50% of the prepolymer, the organic solvent composition, and the aqueous dispersion medium shown in Table 1, and each mixed liquid is stirred at 11000 rpm using a TK homomixer. The toner particle diameter in each emulsion was measured. The results are shown in Table 2.

Example 1 (Example of toner production)
After mixing 440 g / min of 50% prepolymer and 3560 g / min of the organic solvent composition with a static mixer (manufactured by Noritake Engineering Co., Ltd.), the aqueous dispersion medium was pipeline homogenized at a speed of 6000 g / min. The mixture was supplied to a mixer (manufactured by Special Machine Industries) to obtain an emulsified dispersion. The discharge coefficient of the pipeline homomixer was 0.15, the rotation speed was 2960 rotations, and the blade diameter was 0.11 m.
Further, the obtained emulsion was processed as follows to obtain a toner. First, the solvent removal process was performed by the following method. The temperature was raised to 45 ° C., and the solvent was removed under an atmospheric pressure (101.3 kPa) at an outer peripheral edge peripheral speed of 10.5 m / sec. The solvent removal time required 5 hours. Thereafter, after filtration, washing and drying, a toner base was obtained. Next, 100 parts of the obtained base particles and 0.25 part of a charge control agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) were mixed using a Q-type mixer (manufactured by Mitsui Mining Co., Ltd.). Furthermore, 0.5 part of hydrophobic silica (H2000, manufactured by Clariant Japan) was added and mixed. Further, 0.5 part of hydrophobic silica and 0.5 part of hydrophobized titanium oxide were mixed with a Henschel mixer, and coarse particles were removed with a screen having an opening of 37 μm to obtain yellow toner (1). The obtained toner particles had a volume average particle size of 5.3 μm, a number average particle size of 4.7 μm, and an average circularity of 0.96.

Example 2 (Example of toner production)
In Example 1, the same procedure as in Example 1 was repeated except that the 50% prepolymer was changed to 420 g / min, the organic solvent composition was changed to 3380 g / min, and the aqueous dispersion medium (1) was changed to 6200 g / min. 2) was obtained. The obtained toner particles had a volume average particle diameter of 6.4 μm, a number average particle diameter of 5.6 μm, and an average circularity of 0.96.

Example 3 (Example of toner production)
In Example 1, yellow toner (3) was prepared in the same manner as in Example 1 except that the 50% prepolymer was changed to 450 g / min, the organic solvent composition was changed to 3650 g / min, and the aqueous dispersion medium was changed to 6200 g / min. Obtained. The obtained toner particles had a volume average particle diameter of 6.4 μm, a number average particle diameter of 5.6 μm, and an average circularity of 0.96.

Comparative Example 1 (Example of toner production)
In Example 1, an emulsion was obtained in the same manner as in Example 1 except that the 50% prepolymer was changed to 460 g / min, the organic solvent composition was changed to 3740 g / min, and the aqueous dispersion medium was changed to 5800 g / min. did. The toner particles in the obtained emulsion had a volume average particle diameter of 10.0 μm and a number average particle diameter of 6.7 μm. In order to obtain toner particles having a smaller particle size, the number of rotations of the pipeline homomixer was increased to 3040. However, the particle size increased and oil and water separated. The number of rotations of the pipeline homomixer was lowered to 2780 rotations to obtain an emulsion. The volume average particle diameter of the toner particles in the obtained emulsion was 6.4 μm, the number average particle diameter was 4.3 μm, and the average circularity was 0.91. In the same manner as in Example 1, yellow toner (4) was obtained.

  Image quality was evaluated using the yellow toners (1) to (3). For comparison, the same evaluation was performed using the yellow toner (4). The evaluation items and evaluation methods for the toner are as follows.

<Image quality>
The background stain and toner scattering were evaluated, and when good results were obtained for each evaluation item, it was determined that the image quality was good. The evaluation method for each item is as follows.
(Dirt)
The degree of toner contamination on the transfer paper upper surface was visually evaluated.
(Toner scattering)
The state of toner contamination in the copying machine was visually evaluated.
The background stain and the toner scattering were evaluated using an Ricoh IPSIO color 8000 remodeling machine after each image was subjected to a continuous 50000 sheet output durability test using a 5% image area ratio chart.

Table 3 shows the average particle diameter, the particle size distribution, the average circularity of the toner particles and the evaluation results of the toners in Examples 1 to 3 and Comparative Example 1.

  As can be seen from Table 3, the yellow toners (1) to (3) produced using Examples 1 to 3 according to the present invention have obtained toners with a sharp particle size distribution. Excellent results were obtained. On the other hand, the yellow toner (4) produced using Comparative Example 1 has a very fine powder and a broad particle size distribution toner. In the image quality evaluation, both the background stain and the scattering occur. Inferior results were obtained.

It is a graph showing the relationship between the weight ratio (%) of the organic-solvent composition with respect to the pre-mixed solution under fixed shredding force conditions, and a volume average particle diameter. It is the schematic for demonstrating the process cartridge of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Latent image carrier 2 Charging means 4 Developing means 5 Cleaning means

Claims (14)

  Production of a toner having an emulsifying and dispersing step of mixing an organic solvent composition containing at least a binder resin and a colorant in an organic solvent in an aqueous medium, and applying a shearing force to the mixed solution to obtain an emulsion. The volume average particle size of toner particles present in an emulsion obtained when the weight ratio of the organic solvent composition to the aqueous medium in the mixed solution is varied within the range of 60:40 to 20:80. The diameter was measured, and the relationship between the weight ratio [%] of the organic solvent composition to the total mixed solution under a constant shear force condition and the volume average particle diameter was −6.0 to +6.0 (μm /%). A method for producing an electrostatic charge image developing toner, comprising carrying out an emulsification dispersion step within the range of the weight ratio [%] of the organic solvent composition.   The emulsifying and dispersing step is a step of obtaining an emulsion by applying a shearing force while continuously supplying the organic solvent composition and the aqueous medium to a dispersing machine or an emulsifying machine, and the emulsion is dispersed under a constant shearing force condition. 2. The electrostatic charge according to claim 1, wherein the relationship between the weight ratio [%] of the organic solvent composition to the mixed solution and the volume average particle diameter is −1.5 to +3.0 (μm /%). A method for producing a toner for image development.   3. The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein at least the binder resin in the organic solvent composition contains a polyester resin.   In the production method, the total amine value of the organic solvent composition is 1.0 to 10.0 (KOH mg / g), and the total amine value of the organic solvent composition is 0.20 to 0.40 (KOH mg / g). Measure the volume average particle size of the toner particles present in the emulsion obtained by varying within each range, and obtain by the least square method when linearly approximating the relationship between the total amine value and the volume average particle size. The emulsification dispersion step is performed within a range where the correlation coefficient (R2) is 0.9 or more and the slope of the approximate expression is -0.2 to -8. The method for producing a toner for developing an electrostatic charge image according to any one of the above.   In the said manufacturing method, the acid value of an organic-solvent composition is 2-30 KOHmg / g, The manufacturing method of the toner for electrostatic image development as described in any one of Claims 1-4 characterized by the above-mentioned.   In the production method, the organic solvent composition is a solution in which at least a polymer having a site capable of reacting with a compound having an active hydrogen group and a colorant are dissolved or dispersed in the organic solvent. 6. A step of reacting a polymer having a site capable of reacting with a compound having an active hydrogen group after being dispersed by a mechanical shearing force in an aqueous medium or while being dispersed. The method for producing a toner for developing an electrostatic charge image according to any one of the above.   The toner for electrostatic image development according to any one of claims 1 to 6, wherein in the production method, the volume average particle diameter of the toner particles present in the obtained emulsion is 3 to 8 µm. Manufacturing method.   In the above production method, a ratio of the volume average particle diameter to the number average particle diameter of the toner particles present in the toner particle dispersion after removal of the organic solvent is obtained after the toner emulsification dispersion process. (Dv / Dn) is 1.20 or less, The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 7.   The electrostatic charge image according to any one of claims 1 to 8, wherein in the production method, the average circularity of toner particles present in the obtained emulsion is 0.92 to 1.00. A method for producing a developing toner.   An electrostatic image developing toner produced using the method for producing an electrostatic image developing toner according to claim 1.   A developer comprising the electrostatic image developing toner according to claim 10.   An electrostatic image developing toner-containing container, wherein the electrostatic image developing toner according to claim 10 is contained in a container.   An image forming apparatus using the electrostatic charge image developing toner according to claim 10.   In a process cartridge that integrally supports a latent image carrier and at least one unit selected from a charging unit, a developing unit, and a cleaning unit and is detachable from the main body of the image forming apparatus, the developing unit is an electrostatic image developing toner. The process cartridge according to claim 10, wherein the toner for developing an electrostatic image is the toner for developing an electrostatic image according to claim 10.

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