JP4616043B2 - Toner for developing electrostatic image, developer, process cartridge, image forming method, and image forming apparatus - Google Patents

Description

  The present invention relates to an electrostatic charge image developing toner used in an electrophotographic apparatus or an electrostatic recording apparatus, a developer using the toner, a process cartridge, an image forming method, and an image forming apparatus.

  In electrophotographic devices and electrostatic recording devices, toner is attached to an electrostatic latent image formed on a photoreceptor, transferred to a transfer material, and then fixed to the transfer material by heat to form a toner image. is doing. Also, full-color image formation is generally performed by using four color toners of black, yellow, magenta, and cyan. Each toner is developed, and each toner layer is superimposed on a transfer material. To obtain a full-color image.

  However, for users who are familiar with printing in general, images on full-color copiers are not yet satisfactory, and there is a demand for higher image quality that satisfies photography, high-definition, and high resolution. It is known to use a toner having a small particle size and a narrow particle size distribution to improve the image quality.

  Conventional pulverized toner is produced by melting and uniformly dispersing a colorant, a charge control agent, an anti-offset agent, etc. in a thermoplastic resin, and pulverizing and classifying the resulting composition. In such a toner manufacturing method, a high-range particle size distribution is likely to be formed, and when trying to obtain a copy image having good resolution and gradation, for example, a fine particle having a particle size of 5 μm or less and a particle size of 20 μm or more are used. The coarse powder has to be removed by classification, and there is a disadvantage that the yield becomes very low. Particularly in the case of a color toner, it is difficult to uniformly disperse a colorant, a charge control agent and the like in a thermoplastic resin by the pulverization method. The non-uniform dispersion of the compounding agent adversely affects toner fluidity, developability, durability, image quality, and the like.

In recent years, in order to overcome these problems in the pulverization method, a toner production method by a suspension polymerization method has been proposed and implemented. A technique for producing a toner for developing an electrostatic latent image by a polymerization method is known. For example, toner particles are obtained by a suspension polymerization method.
According to the polymerization method, the conventional pulverization process and kneading process can be omitted, energy saving, shortening of production time, improvement of process yield, etc. contribute greatly to cost reduction. At the same time, it is easy to make the particle size distribution sharper than that of the pulverization method, and the contribution to high image quality is great, so the polymerization method is a highly promising method.

In addition, in order to increase the image quality of a full-color image as in printing in electrophotography, it is necessary that each toner has a wide color reproducibility. In order to achieve the above object without any problems, a colorant having excellent transparency, light resistance and heat resistance is highly dispersed in the toner.
Conventionally known colorants for yellow toner have many problems. For example, although dye-based colorants are generally excellent in transparency, they are inferior in light resistance and have a problem in image storage stability.

In addition, although the pigment system is superior in light resistance as compared with the dye, there is still a problem in light resistance as compared with the copper phthalocyanine pigment used for magenta toner.
Furthermore, even a yellow pigment having excellent light resistance and heat resistance has a concealment property that is too strong, and the transparency is extremely lowered, which is not suitable for full color use.

Patent Document 1 introduces a disazo compound excellent in light resistance and a production method thereof. This is a group of compounds represented by Pigment Yellow 180, and is one of the azo pigments that not only excels in light resistance and heat resistance, but also meets recent safety requirements.
A yellow toner using Pigment Yellow 180 is described in Patent Document 2, Patent Document 3, and Patent Document 4 Japanese Patent Application Laid-Open No. 8-262799. However, a toner using the above pigment has poor coloring power, and additionally has transparency. Although it is not good at all, it is actively used as a pigment for pulverized toner because of the above characteristics.

  In addition, in the case of chemical toners, the presence state of the pigment may change depending on the characteristics derived from the pigment as compared with the kneaded and pulverized toner. Due to the dispersibility and dispersion stability of the pigment within the particles, the pigment is likely to agglomerate during granulation or the pigment is deposited on the particle surface, which can cause changes in fixability and chargeability. It was. Pigment Yellow 180 has a relatively high hydrophilicity and can be used by segregating on the particle surface or reaggregating in the particle in a method of dispersing the oil phase in water such as suspension polymerization. Have difficulty.

  On the other hand, Patent Document 5, Patent Document 6, Patent Document 7, Patent Document 8, and Patent Document 9 show examples using Pigment Yellow 155. This pigment has relatively good spectral characteristics and has been shown to be applied in various polymerization methods and grinding methods. Pigment Yellow 180 is extremely hydrophilic, and it is relatively easy to apply to chemical toners because it does not require excessive surface treatment. There was a problem that the dispersion stability in the liquid was poor.

JP-B-2-37949 JP-A-6-230607 JP-A-6-266163 JP-A-8-262799 Japanese Patent Laid-Open No. 2004-212451 JP 2001-166540 A JP 2001-109196 A JP-A-11-202558 Japanese Patent Application Laid-Open No. 07-230184

An object of the present invention is to provide a toner, a developer, a developing method, and a developing device that have solved the above-described problems. That is: To provide a toner, an image forming apparatus, and an image forming method capable of obtaining image quality with sufficient image density while ensuring developability, transferability and fixability without excessive uneven distribution of pigment on the surface.
2. The toner has a sufficiently high charging capability, good charge rise characteristics, and even if tens of thousands of images are output, there is little toner spent on the carrier, etc., and high chargeability and fluidity can be maintained. To provide an image forming apparatus and an image forming method capable of obtaining an image quality with a small image density and sufficient image density.
3. It is another object of the present invention to provide a toner having excellent weather resistance and no hue change over a long period of time, an image forming apparatus, and an image forming method.

As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that the toner satisfying the following conditions (1) to (3) is preferable in a toner containing at least a colorant and a resin.
(1) A toner comprising base particles and inorganic oxide fine particles, wherein the colorant is 1) an organic pigment having the following structure with a primary particle size of 0.08 to 0.12 μm, and 2) a primary particle size of 0.01. It consists of two types of organic pigments having the same structure of ~ 0.06 μm.

(2) The mixing ratio of the colorant (1) and the colorant (2) is 10:90 to 50:50 by weight.
(3) Use a masterbatch containing a binder resin and a colorant.

  The above pigment is used by being finely dispersed in the toner. However, the relatively strong hydrophilic azo pigment has a problem that separation from the resin is likely to occur unless the hydrophilicity of the resin is increased. Above all, the above pigments are relatively strong in association and cohesion. Therefore, in the toner production process, when the pigment passes through a state where the pigment is present in the liquid, such as melting, dissolving, or dispersing in the monomer. Further, reaggregation of the pigment occurs, and as a result, the transparency of the toner may be lowered. In particular, in the production process of chemical toners such as various polymerization methods and dissolution suspension methods, the viscosity of the resin solution is remarkably increased, and it is difficult to control the particle size during granulation, and the precipitation of pigment on the toner surface is remarkable. In addition, the toner obtained has a problem that the melt viscosity at the time of heat melting tends to be higher than that of other pigments.

  Therefore, as a result of intensive studies, the pigment having the same structure, in particular, has a primary particle diameter of the pigment in a specific range in advance, thereby preventing the aggregation of the pigment in the liquid and obtaining the chemical toner. It has been found that good toner performance can be obtained without causing problems such as a decrease in transparency due to agglomeration, uneven surface distribution of the pigment, and an increase in viscosity at the time of melting.

  The primary particle diameter of the pigment is preferable when the 50% diameter of the particle size distribution is in the range of 0.08 to 0.12 μm without causing the above problems. On the other hand, when the primary particle diameter of the pigment is less than 0.08 μm, the transparency of the toner can be obtained, but the viscosity of the previous solution is increased, the fixing property is inhibited, and the pigment is likely to be unevenly distributed. On the other hand, if it exceeds 0.12 μm, the transparency of the toner is impaired, which is not preferable.

  Therefore, in addition to the primary particle diameter of the pigment being 0.08 to 0.12 μm as described above, the pigment having a primary particle diameter of 0.01 to 0.06 μm is used in combination to improve the transparency of the toner. It is possible to improve without losing.

The toner is preferably a toner for developing electrostatic images characterized in that it contains at least a polyester resin, since the dispersibility of the pigment is stable without extremely increasing the polarity of the polyester resin, and thus the above-mentioned problems do not occur. The toner preferably contains at least a modified polyester resin, so that the viscoelasticity of the resin can be appropriately controlled.
The above effect is remarkable in a chemical toner, particularly a toner mainly composed of polyester.
Thus, according to the present invention, the following toner is provided.

（２）前記母体粒子表面に帯電制御剤としてフッ素系４級アンモニウム塩化合物を有することを特徴とする上記（１）の静電荷像現像用トナー。
（３）少なくとも結着樹脂として変性ポリエステル樹脂を含むことを特徴とする上記（１）、（２）の静電荷像現像用トナー。
（４）トナー粒子の平均円形度Ｅが０．９０〜０．９９の形状であることを特徴とする上記（１）〜（３）の静電荷像現像用トナー。 (1) a toner comprising a base particle of a toner composition is prepared dissolving or oil droplets dispersed organic solvent is dispersed in an aqueous medium containing a masterbatch comprising at least a colorant and a binder resin, at least includes a polyester resin as the binder resin, the mixing of the coloring agent, Ri Do two kinds of the following colorant (1) and a colorant (2), the colorant (1) and a colorant and (2) A toner for developing electrostatic images, wherein the ratio is 10:90 to 60:40 by weight .
Colorant [1]: Organic pigment represented by the above chemical formula (1) having a primary particle diameter (50% diameter) of 0.08 to 0.12 μm Colorant [2]: Primary particle diameter (50% diameter) Organic pigment represented by the chemical formula (1) having a thickness of 01 to 0.06 μm

(2) The toner for developing an electrostatic charge image according to (1) above , which has a fluorine-based quaternary ammonium salt compound as a charge control agent on the surface of the base particle .
(3) The electrostatic image developing toner according to (1) or (2) above, wherein the toner comprises at least a modified polyester resin as a binder resin.
(4) The electrostatic image developing toner according to (1) to (3) above, wherein the toner particles have an average circularity E of 0.90 to 0.99.

(5) The electrostatic charge image development described in (1) to (4) above, wherein the toner particles have a circularity SF-1 value of 100 to 150 and a circularity SF-2 value of 100 to 140. Toner.
(6) The volume average particle diameter Dv of the toner particles is 2 to 7 μm, and the ratio Dv / Dn of the volume average particle diameter Dv to the number average particle diameter Dn is 1.25 or less (1) ) To (5) toners for developing electrostatic images.
(7) For electrostatic image development according to (1) to (6) above, wherein the mixing ratio of the colorant (1) and the colorant (2) is 30:70 to 60:40 by weight. Yellow toner.
(8) The toner is composed of particles formed by dispersing oil droplets of an organic solvent in which a toner composition containing a prepolymer is dissolved in an aqueous medium, and by an extension reaction and / or a crosslinking reaction. 1. Toner for developing electrostatic images of (1) to (7).

( 9 ) A two-component developer comprising at least the toner for developing an electrostatic charge image of (1) to ( 8 ) and a carrier made of magnetic particles.
( 10 ) In a process cartridge that integrally supports at least one unit selected from a photosensitive member, 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 includes: A process cartridge for holding a toner, wherein the toner is the toner for developing an electrostatic charge image according to the above (1) to ( 8 ).
( 11 ) The electrostatic image on the electrostatic image carrier is developed with an electrostatic image developing developer to form a toner image, and a transfer means is brought into contact with the surface of the electrostatic image carrier via a transfer material. An image forming apparatus for electrostatically transferring an image onto a transfer material, wherein the developer is the two-component developer of ( 9 ).
( 12 ) An image forming method comprising forming an image using the image forming apparatus according to ( 11 ).

  According to the present invention, it is possible to provide a yellow toner having good transparency and having no problems of fixing property and charging property.

  Hereinafter, the present invention will be described in detail. Here, the toner, the manufacturing method and material of the developer, and the overall system relating to the electrophotographic process that are used in the present invention can be used as long as the conditions are satisfied.

(Coloring agent)
The colorant of the present invention is a yellow pigment having a chemical structure represented by the following chemical formula (1) and having a particle diameter in the range of 0.08 to 0.12 μm.

The primary particle diameter (50% diameter) of the colorant in the present invention is obtained as follows.
First, a pigment is sampled on a collodion film, and a particle image of the pigment is obtained by TEM observation. In this case, the measurement magnification is 35000 times.
From the TEM photograph, individual particle diameters are determined for 500 to 1000 pigment particles. The pigment particle diameter is the ferret diameter. Next, an integrated distribution of particle diameters is obtained, and the 50% diameter is taken as the representative diameter of the approximate pigment.
The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% 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 modified and unmodified polyester resins mentioned above, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and polymers of substituted products 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, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α- Chloromethyl methacrylate copolymer, Tylene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid Styrene copolymers such as acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, poly Acrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. The

  This master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force. In this case, an organic solvent can be used to enhance the interaction between the colorant and the resin. In addition, a so-called flushing method, which is a wet cake of a coloring agent, is a method of mixing and kneading an aqueous paste containing water of a coloring agent together with a resin and an organic solvent, transferring the coloring agent to the resin side, and removing moisture and organic solvent components. Can be used as it is, so that it is not necessary to dry and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

(Modified polyester resin)
In the present invention, the following modified polyester resins can be used as the polyester resin. For example, a polyester prepolymer having an isocyanate group can be used. Examples of the polyester prepolymer (A) having an isocyanate group include a product obtained by further reacting a polyester having an active hydrogen group with a polyisocyanate (3), which is a polycondensate of polyol (1) and polycarboxylic acid (2). Can be mentioned. Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.

  Examples of the polyol (1) include a diol (1-1) and a tri- or higher valent polyol (1-2). (1-1) alone or (1-1) and a small amount of (1-2) Mixtures are preferred. Diol (1-1) includes alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic 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. The trihydric or higher polyol (1-2) 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 polycarboxylic acid (2) include dicarboxylic acid (2-1) and trivalent or higher polycarboxylic acid (2-2). (2-1) alone and (2-1) with a small amount of ( The mixture of 2-2) is preferred. Dicarboxylic acid (2-1) includes alkylene dicarboxylic acid (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acid (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acid (phthalic acid, isophthalic acid, terephthalic acid) 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 polycarboxylic acid (2-2) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (trimellitic acid, pyromellitic acid, and the like). In addition, as polycarboxylic acid (2), you may make it react with polyol (1) using the acid anhydride or lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) of the above-mentioned thing.

  The ratio of the polyol (1) to the polycarboxylic acid (2) 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 (3) 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; And a combination of two or more of these.

  The ratio of the polyisocyanate (3) is usually 5/1 to 1/1, preferably 4 /, as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. If the molar ratio of [NCO] is less than 1, the urea content in the modified polyester will be low, and the hot offset resistance will deteriorate. The content of the polyisocyanate (3) component in the prepolymer (A) having an isocyanate group at the terminal is usually 0.5 to 40% by weight, preferably 1 to 30% by weight, more preferably 2 to 20% by weight. It is. If it is less than 0.5% by weight, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40% by weight, the low-temperature fixability deteriorates.

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

(Crosslinking agent and extender)
In the present invention, amines can be used as a crosslinking agent and / or an extender. As amines (B), diamine (B1), trivalent or higher polyamine (B2), aminoalcohol (B3), aminomercaptan (B4), amino acid (B5), and amino acids B1-B5 blocked (B6) etc. are mentioned.

  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), preferred are B1 and a mixture of B1 and a small amount of B2.

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

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

(Unmodified polyester)
In the present invention, it is important not only to use the modified polyester (A) alone, but also to contain the unmodified polyester (C) as a toner binder component together with the (A). By using (C) in combination, the low-temperature fixability and the glossiness when used in a full-color apparatus are improved. Examples of (C) include the same polycondensates of polyol (1) and polycarboxylic acid (2) as in the polyester component (A), and preferred ones are also the same as (A). (C) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, and may be modified with, for example, a urethane bond.

  It is preferable that (A) and (C) are at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component (A) and (C) preferably have similar compositions. When (A) is contained, the weight ratio of (A) to (C) is usually 5/95 to 75/25, preferably 10/90 to 25/75, more preferably 12/88 to 25/75, Especially preferably, it is 12 / 88-22 / 78. If the weight ratio of (A) is less than 5%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

  The peak molecular weight of (C) is usually 1000-30000, preferably 1500-10000, more preferably 2000-8000. If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 30000, low-temperature fixability will deteriorate. The hydroxyl value of (C) is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

  The acid value of (C) is usually from 0.5 to 40, preferably from 5 to 35. By having an acid value, it tends to be negatively charged. Further, those having an acid value and a hydroxyl value exceeding these ranges are easily affected by the environment under high temperature and high humidity and low temperature and low humidity, and are liable to cause image deterioration.

  In the present invention, the glass transition point (Tg) of the toner is usually 40 to 70 ° C., preferably 45 to 55 ° C. If it is less than 40 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of the crosslinked and / or elongated polyester resin, the toner for developing an electrostatic charge image of the present invention exhibits good storage stability even when the glass transition point is low, as compared with known polyester-based toners.

As the storage elastic modulus of the toner, the temperature (TG ′) at which the measurement frequency is 20 Hz is 10000 dyne / cm ² is usually 100 ° C. or higher, preferably 110 to 200 ° C. If it is less than 100 ° C., the resistance to hot offset deteriorates. As the viscosity of the toner, the temperature (Tη) at 1000 poise at a measurement frequency of 20 Hz is usually 180 ° C. or less, preferably 90 to 160 ° C. If it exceeds 180 ° C., the low-temperature fixability deteriorates. That is, TG ′ is preferably higher than Tη from the viewpoint of achieving both low temperature fixability and hot offset resistance. In other words, the difference between TG ′ and Tη (TG′−Tη) is preferably 0 ° C. or higher. More preferably, it is 10 degreeC or more, Most preferably, it is 20 degreeC or more. The upper limit of the difference is not particularly limited. Further, from the viewpoint of achieving both heat-resistant storage stability and low-temperature fixability, the difference between Tη and Tg is preferably 0 to 100 ° C. More preferably, it is 10-90 degreeC, Most preferably, it is 20-80 degreeC.

(Release agent)
Further, a wax may be contained together with the toner binder and the colorant. Known waxes can be used as the wax of the present invention, such as polyolefin wax (polyethylene wax, polypropylene wax, etc.); long chain hydrocarbon (paraffin wax, sasol wax, etc.); carbonyl group-containing wax, etc. It is done.

  Of these, carbonyl group-containing waxes are preferred. Examples of the carbonyl group-containing wax include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18. -Octadecanediol distearate, etc.); polyalkanol esters (trimellitic acid tristearyl, distearyl maleate, etc.); polyalkanoic acid amides (ethylenediamine dibehenyl amide, etc.); polyalkylamides (trimellitic acid tristearyl amide, etc.) And dialkyl ketones (such as distearyl ketone). Among these carbonyl group-containing waxes, polyalkanoic acid esters are preferred.

  The melting point of the wax of the present invention is usually 40 to 160 ° C, preferably 50 to 120 ° C, more preferably 60 to 90 ° C. A wax having a melting point of less than 40 ° C. has an adverse effect on heat resistant storage stability, and a wax having a melting point of more than 160 ° C. tends to cause a cold offset when fixing at a low temperature. Further, the melt viscosity of the wax is preferably 5 to 1000 cps, more preferably 10 to 100 cps as a measured value at a temperature 20 ° C. higher than the melting point. Waxes exceeding 1000 cps have poor effects for improving hot offset resistance and low-temperature fixability. The content of the wax in the toner is usually 0 to 40% by weight, preferably 3 to 30% by weight.

(Charge control agent)
The toner of the present invention may contain a charge control agent as necessary. Any 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 (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 a phenol-based condensate (manufactured by Orient Chemical Industry Co., Ltd.), TP-302 of a quaternary ammonium salt molybdenum complex, TP-415 (manufactured by Hodogaya Chemical Industry 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 Co., Ltd.), copper phthalocyanine, perylene, quinaclide And azo pigments, and other high molecular compounds having a functional group such as a sulfonic acid group, a carboxyl group, and a quaternary ammonium salt.

  In the present invention, the amount of charge control agent used is determined by the toner production method including the type of binder resin, the presence or absence of additives used as necessary, and the dispersion method, and is uniquely limited. However, it is preferably used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the 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 an external additive for assisting fluidity, developability and chargeability of the colored particles obtained in the present invention, oxide fine particles, other inorganic fine particles, and hydrophobic treated inorganic fine particles can be used in combination. More preferably, the hydrophobic treated primary particles contain at least one kind of inorganic fine particles having an average particle size of 1 to 100 nm, more preferably 5 to 70 nm. Further, it is more preferable that the hydrophobized primary particles contain at least one kind of inorganic fine particles having an average particle diameter of 20 nm or less and at least one kind of inorganic fine particles of 30 nm or more. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g.
Any of them can be used as long as the conditions are satisfied. For example, silica fine particles, hydrophobic silica, fatty acid metal salts (such as zinc stearate and aluminum stearate), metal oxides (such as titania, alumina, tin oxide, and antimony oxide), fluoropolymers, and the like may be contained.

  Particularly suitable additives include hydrophobized silica, titania, titanium oxide, and alumina fine particles. Silica fine particles include HDKH 2000, HDK H 2000/4, HDK H 2050EP, HVK21, HDK H 1303 (above Hoechst) and R972, R974, RX200, RY200, R202, R805, and R812 (above Nippon Aerosil). Further, as titania fine particles, P-25 (Nippon Aerosil), STT-30, STT-65C-S (above Titanium Industry), TAF-140 (Fuji Titanium Industry), MT-150W, MT-500B, MT-600B MT-150A (taker above). Particularly, the hydrophobized titanium oxide fine particles include T-805 (Nippon Aerosil), STT-30A, STT-65S-S (above Titanium Industry), TAF-500T, TAF-1500T (above Fuji Titanium Industry), MT -100S, MT-100T (above Taka), IT-S (Ishihara Sangyo), etc.

  In order to obtain hydrophobized oxide fine particles, silica fine particles, titania fine particles, and alumina fine particles, hydrophilic fine particles are treated with a silane coupling agent such as methyltrimethoxysilane, methyltriethoxysilane, or octyltrimethoxysilane. Can be obtained. In addition, silicone oil-treated oxide fine particles and inorganic fine particles obtained by treating silicone oil with heat if necessary to treat it with inorganic fine particles are also suitable.

  Examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, chlorophenyl silicone oil, methyl hydrogen silicone oil, alkyl modified silicone oil, fluorine modified silicone oil, polyether modified silicone oil, alcohol modified silicone oil, amino modified silicone. Oil, epoxy-modified silicone oil, epoxy-polyether-modified silicone oil, phenol-modified silicone oil, carboxyl-modified silicone oil, mercapto-modified silicone oil, acrylic, methacryl-modified silicone oil, α-methylstyrene-modified silicone oil and the like can be used. Examples of the inorganic fine particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, iron oxide, copper oxide, zinc oxide, tin oxide, quartz sand, clay, mica, and silica ash. Examples thereof include stone, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, parium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Of these, silica and titanium dioxide are particularly preferred.

  The addition amount can be 0.1 to 5% by weight, preferably 0.3 to 3% by weight, based on the toner. The average particle size of the primary particles of the inorganic fine particles is 100 nm or less, preferably 3 nm or more and 70 nm or less. If it is smaller than this range, the inorganic fine particles are buried in the toner, and the function is hardly exhibited effectively. On the other hand, if it is larger than this range, the surface of the photoreceptor is not uniformly damaged.

  In addition, polymer fine particles such as polystyrene obtained by soap-free emulsion polymerization, suspension polymerization and dispersion polymerization, methacrylic acid ester and acrylic acid ester copolymer, polycondensation system such as silicone, benzoguanamine and nylon, thermosetting resin And 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.

(Resin fine particles)
In the present invention, resin fine particles can be contained as required. The resin fine particles used have a glass transition point (Tg) of 40 to 100 ° C., a weight average molecular weight of 9000 to 200,000 is more preferable, and as described above, the glass transition point (Tg) is less than 40 ° C., and When the weight average molecular weight is less than 9,000, the storage stability of the toner is deteriorated, and blocking occurs during storage and in the developing machine. When the glass transition point (Tg) is more than 100 ° C. and / or the weight average molecular weight is more than 200,000, the resin fine particles inhibit the adhesiveness to the fixing paper, and the fixing minimum temperature is increased.

  More preferably, the residual ratio with respect to the toner particles is 0.5 to 5.0 wt%. When the residual ratio is less than 0.5 wt%, the storage stability of the toner deteriorates, and blocking occurs during storage and in the developing machine. When the residual amount exceeds 5.0 wt%, the resin fine particles Inhibits the exudation of the wax, the effect of releasing the wax is not obtained, and the occurrence of offset is observed.

  The residual rate of the resin fine particles can be measured by analyzing a substance caused by the resin fine particles, not by the toner particles, using a pyrolysis gas chromatograph mass spectrometer, and calculating from the peak area. The detector is preferably a mass spectrometer, but is not particularly limited.

  The resin fine particles may be any resin as long as it can form an aqueous dispersion, and may be a thermoplastic resin or a thermosetting resin. For example, vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimides Examples thereof include resins, silicon-based resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, and polycarbonate resins. As the resin fine particles, 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.

  The vinyl resin is a polymer obtained by homopolymerization or copolymerization of a vinyl monomer, such as a styrene- (meth) acrylate resin, a styrene-butadiene copolymer, a (meth) acrylic acid-acrylate polymer, Examples include styrene-acrylonitrile copolymers, styrene-maleic anhydride copolymers, styrene- (meth) acrylic acid copolymers, and the like.

(Average circularity E)
It is important that the toner in the present invention has a specific shape and shape distribution, and the average circularity E is preferably 0.90 to 0.99. With an irregularly shaped toner less than 0.90 and too far from the spherical shape, satisfactory transferability and high-quality images free from dust cannot be obtained. On the other hand, if it exceeds 0.99, it becomes a perfect sphere, which is not preferable because of poor cleaning performance.

  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. The average circularity E 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. In order for the toner to form a high-definition image having a reproducibility with an appropriate density, the average circularity E is more preferably 0.94 to 0.99. When attention is paid to the ease of cleaning, it is more preferable that the average circularity E is 0.94 to 0.99 and the particles having a circularity of less than 0.94 is 10% or less.

  The apparatus can measure the average circularity E with a flow particle image analyzer FPIA-2100 (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 for about 1 to 3 minutes with an ultrasonic disperser and measuring the shape and distribution of the toner with the above apparatus at a dispersion concentration of 3000 to 10,000 / μl. .

(Circularity SF-1, SF-2)
The shape factors SF-1 and SF-2, which are the circularity used in the present invention, are obtained by randomly sampling 300 SEM images of toner obtained by measurement with a FE-SEM (S-4200) manufactured by Hitachi, Ltd. The image information was introduced into an image analysis apparatus (Luzex AP) manufactured by Nireco through an interface and analyzed, and the values obtained from the following equations were defined as SF-1 and SF-2. The values of SF-1 and SF-2 are preferably values obtained by Luzex, but are not particularly limited to the FE-SEM device and the image analysis device as long as similar analysis results can be obtained.

SF-1 = (L ² / A) × (π / 4) × 100
SF-2 = (P ² / A) × (1 / 4π) × 100
Here, L, A, and P are defined as follows.
L: Absolute maximum length of toner A: Projected area of toner P: Maximum circumference of toner

  In the case of a true sphere, all become 100, and from a spherical shape to an indefinite shape as the value becomes larger than 100. In particular, SF-1 represents the shape of the entire toner (ellipse, sphere, etc.), and SF-2 is a shape factor indicating the degree of surface irregularities.

(Volume average particle diameter, Dv / Dn (volume average particle diameter / number average particle diameter ratio))
The volume average particle diameter (Dv) of the toner of the present invention is more preferably 2 to 7 μm, and the ratio (Dv / Dn) to the number average particle diameter (Dn) is 1.25 or less, preferably 1.10 to 1.25. The dry toner is excellent in heat-resistant storage stability, low-temperature fixability, and hot offset resistance, and particularly excellent in image gloss when used in a full-color copying machine. Even if the toner balance is extended, the fluctuation of the toner particle diameter in the developer is reduced, and good and stable developability can be obtained even with long-term stirring in the developing device.

  Further, when used as a one-component developer, even if the balance of the toner is performed, the fluctuation of the toner particle diameter is reduced, and the toner filming on the developing roller and the toner layer are made thin. There was no fusion of toner to a member such as a blade, and good and stable developability and images were obtained even during long-term use (stirring) of the developing device. In particular, when inorganic fine particles that are surface-treated with at least both a fluorine-containing compound and a silicon-containing compound of the present invention are used as a fluidizing agent, the particle size distribution is reduced because the margin for filming is reduced due to the influence of fluorine groups. More preferred.

In general, it is said that the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning properties. is there. Further, when the volume average particle diameter is smaller than the range of the present invention, in the case of the two-component developer, the toner is fused to the surface of the carrier during a long period of stirring in the developing device, and the charging ability of the carrier is reduced, When used as an agent, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur.
Further, these phenomena are the same for the toner having a fine powder content larger than the range of the present invention. On the contrary, when the particle diameter of the toner is larger than the range of the present invention, it becomes difficult to obtain a high resolution and high quality image, and when the balance of the toner in the developer is performed, In many cases, the variation of the particle size becomes large. It was also clarified that the same applies when the volume average particle diameter / number average particle diameter is larger than 1.25.

(Production method)
The toner binder can be produced by the following method. The polyol (1) and the polycarboxylic acid (2) are heated to 150 to 280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and the generated water is distilled off as necessary. Thus, a polyester having a hydroxyl group is obtained. Next, this is reacted with polyisocyanate (3) at 40 to 140 ° C. to obtain a prepolymer (A) having an isocyanate group.

The dry toner of the present invention can be produced by the following method, but is not limited thereto.
(Toner production method in aqueous medium)
The aqueous phase used in the present invention is used by adding resin fine particles in advance. The water used for the aqueous phase may be water alone, or a solvent miscible with water may be used in combination. Examples of the miscible solvent include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.

  The toner particles are obtained by forming a dispersion composed of a polyester prepolymer (A) having an isocyanate group dissolved or dispersed in an organic solvent in an aqueous phase and reacting with amines (B). As a method for stably forming a dispersion comprising a polyester prepolymer (A) in an aqueous phase, a composition of a toner raw material comprising a polyester prepolymer (A) dissolved or dispersed in an organic solvent in an aqueous phase is added. And a method of dispersing by shearing force.

  Polyester prepolymer (A) dissolved or dispersed in an organic solvent and other toner composition (hereinafter referred to as toner raw material), colorant masterbatch, release agent, charge control agent, unmodified The polyester resin or the like may be mixed when forming the dispersion in the aqueous phase, but after the toner raw material is mixed in advance and dissolved or dispersed in an organic solvent, the mixture is added to the aqueous phase and dispersed. Is more preferable. In the present invention, other toner raw materials such as a colorant, a release agent, and a charge control agent do not necessarily have to be mixed when forming particles in the aqueous phase. It may be added. For example, after forming particles containing no colorant, the colorant can be added by a known dyeing 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. In order to make the particle size of the dispersion 2 to 20 μm, a high-speed shearing type is preferable. When a high-speed shearing disperser is used, the number of rotations 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. Higher temperatures are preferred in that the dispersion of the polyester prepolymer (A) has a low viscosity and is easy to disperse.

  The amount of the aqueous phase to be used with respect to 100 parts by weight of the toner composition containing the polyester prepolymer (A) 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 composition is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 20000 parts by weight, it is not economical. Moreover, a dispersing agent can also be used as needed. It is preferable to use a dispersant because the particle size distribution becomes sharp and the dispersion is stable.

  Anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino acids as dispersants for emulsifying and dispersing the oily phase in which the toner composition is dispersed in the aqueous phase Alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, quaternary ammonium such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride Nonionic surfactants such as 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 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 to C11). Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) mono-N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carboxylic acid and metal salt Perfluoroalkylcarboxylic acid (C7 to C13) and its metal salt, perfluoroalkyl (C4 to C12) sulfonic acid and its metal salt, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- (2hydroxyethyl) -Fluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is mentioned.
Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Taikin Kogyo Co., Ltd.), Mega-Fac Fll0, F-120, 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 Fagento F-100, F150 (manufactured by Neos).

Examples of cationic surfactants include aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, benza Luconium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (Asahi Glass), Florard FC-135 (Sumitomo 3M), Unidyne DS-202 (Daikin Industries) , Megafac F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products Co., Ltd.), Footgent F-300 (Neos Co., Ltd.), and the like.
Further, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like can be used as an inorganic compound dispersant which is hardly soluble in water.

  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 Bodies such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-acrylate Chloro-2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N -Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or esters of compounds containing vinyl alcohol and carboxyl groups For example, 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 Homopolymers or copolymers such as those having a nitrogen atom such as imine or a heterocyclic ring thereof, polyoxyethylene, polyoxypropylene, polyethylene Oxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonylphenyl Polyoxyethylenes such as esters, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

If a dispersion stabilizer that is soluble in acids or alkalis such as calcium phosphate is used, the calcium phosphate is removed from the fine particles by dissolving the calcium phosphate with an acid such as hydrochloric acid and then washing with water. To do. It can also be removed by operations such as enzymatic degradation.
When a dispersant is used, the dispersant may remain on the surface of the toner particles, but it is preferable from the charged surface of the toner that the dispersant is washed and removed after the elongation and / or crosslinking reaction.

  The elongation and / or cross-linking reaction time is selected depending on the reactivity of the isocyanate group structure of the prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. is there. 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. Sufficient quality can be obtained with a short treatment such as spray dryer, belt dryer or rotary kiln.

Further, as a method for removing the organic solvent, air can be blown away by a rotary evaporator or the like.
Thereafter, rough separation is performed by centrifugal separation, the emulsified dispersion is washed in a washing tank, and the drying process is repeated in a hot air dryer, and the solvent is removed and dried to obtain a toner base.
Thereafter, a ripening step is further performed, so that the hollow state inside the toner can be controlled, which is more preferable. It is preferably 30 to 55 ° C. (more preferably 40 to 50 ° C.), and more preferably aging for 5 to 36 hours (more preferably 10 to 24 hours).

When the particle size distribution at the time of emulsification dispersion is wide and washing and drying processes are performed while maintaining the particle size distribution, the particle size distribution can be adjusted by classifying into a desired particle size distribution.
In the classification operation, the fine particle portion can be removed in the liquid by a cyclone, a decanter, centrifugation, or the like. Of course, the classification operation may be performed after obtaining the powder as a powder after drying. The unnecessary fine particles or coarse particles obtained can be returned to the kneading step and used for the formation of particles. At that time, fine particles or coarse particles may be wet.
The dispersant used is preferably removed from the obtained dispersion as much as possible, but it is preferable to carry out it simultaneously with the classification operation described above.

  Mixing or giving mechanical impact force to the powder mixture after drying with different types of particles such as release agent fine particles, charge control fine particles, fluidizing agent fine particles, and colorant fine particles By immobilizing and fusing on the surface, it is possible to prevent detachment of foreign particles from the surface of the resulting 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.
Finally, an external additive such as inorganic fine particles and a toner are mixed with a Henschel mixer or the like, and coarse particles are removed with an ultrasonic sieve or the like to obtain a final toner.

(Carrier for two-component developer)
When the toner of the present invention is used for a two-component developer, it may be used by mixing with a magnetic carrier. The carrier to toner content ratio in the developer is 1 to 10 weights of toner with respect to 100 parts by weight of carrier. Part is preferred. As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used.

  Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride And fluoro such as terpolymers of non-fluoride monomers including, and silicone resins.

Moreover, you may contain electrically conductive powder etc. in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.
The toner of the present invention can also be used as a one-component magnetic toner that does not use a carrier or a non-magnetic toner.

(Intermediate transfer member)
In the present invention, an intermediate transfer member can also be used. One embodiment of the intermediate transfer member of the transfer system will be described. FIG. 1 is a schematic configuration diagram of a copying machine according to the present embodiment. Around a photosensitive drum (hereinafter referred to as a photosensitive member) 10 as an image carrier, a charging roller 20 as a charging device, an exposure device 30, a cleaning device 60 having a cleaning blade, a static elimination lamp 70 as a static elimination device, and development. An apparatus 40 and an intermediate transfer member 50 as an intermediate transfer medium are disposed. The intermediate transfer member 50 is suspended by a plurality of suspension rollers 51 and is configured to run endlessly in the direction of the arrow by a driving unit such as a motor (not shown). A part of the suspension roller 51 also serves as a transfer bias roller for supplying a transfer bias to the intermediate transfer member, and a predetermined transfer bias voltage is applied from a power source (not shown). A cleaning device 90 having a cleaning blade for the intermediate transfer member 50 is also provided. Further, a transfer roller 80 is provided as a transfer means for transferring the developed image onto the transfer paper 100 as the final transfer material, facing the intermediate transfer member 50, and the transfer roller 80 is transferred by a power supply device (not shown). Supplied. Around the intermediate transfer member 50, a corona charger 52 as a charge applying unit is provided.

  The developing device 40 includes a developing belt 41 as a developer carrier, a black (hereinafter referred to as “Bk”) developing unit 45K, a yellow (hereinafter referred to as “Y”) developing unit 45Y, The developing unit 45M is hereinafter referred to as magenta and the cyan (hereinafter referred to as C) developing unit 45C. Further, the developing belt 41 is stretched between a plurality of belt rollers, and is configured to run endlessly in a direction indicated by an arrow by a driving unit such as a motor (not shown). Moves at approximately the same speed as 10.

Since the configuration of each developing unit is common, the following description will be given only for the Bk developing unit 45Bk, and for the other developing units 45Y, 45M, and 45C, the portions corresponding to those in the Bk developing unit 50Bk in the figure are Y, M, and C are appended to the numbers given to those in the unit, and the description is omitted. The developing unit 45Bk is disposed so that a developing tank 42Bk containing a high-viscosity and high-concentration liquid developer containing toner particles and a carrier liquid component and a lower part are immersed in the liquid developer in the developing tank 42Bk. And a coating roller 44Bk that thins the developer pumped from the pumping roller 43Bk and applies it to the developing belt 41. The application roller 44Bk has conductivity, and a predetermined bias is applied from a power source (not shown).
In addition to the apparatus configuration as shown in FIG. 1, the apparatus configuration of the copying machine according to the present embodiment is an apparatus configuration in which development units 45 for each color are provided around the photoconductor 10 as shown in FIG. It may be.

  Next, the operation of the copying machine according to the present embodiment will be described. In FIG. 1, the photosensitive member 10 is uniformly charged by the charging roller 20 while being driven to rotate in the direction of the arrow, and then the reflected light from the original is imaged and projected by an optical system (not shown) by the exposure device 30 on the photosensitive member 10. An electrostatic latent image is formed on the surface. This electrostatic latent image is developed by the developing device 40 to form a toner image as a visible image. The developer thin layer on the developing belt 41 is peeled off from the belt 41 in a thin layer state by contact with the photosensitive member in the developing region, and moves to a portion where a latent image is formed on the photosensitive member 10. The toner image developed by the developing device 40 is transferred to the surface of the intermediate transfer member 50 at the contact portion (primary transfer region) between the photosensitive member 10 and the intermediate transfer member 50 moving at a constant speed (primary transfer). Transcription). When transferring three or four colors to be superimposed, this process is repeated for each color to form a color image on the intermediate transfer member 50.

  The corona charger 52 for applying an electric charge to the superimposed toner image on the intermediate transfer member is provided at a contact facing portion between the photosensitive member 10 and the intermediate transfer member 50 in the rotation direction of the intermediate transfer member 50. It is installed on the downstream side and on the upstream side of the contact facing portion between the intermediate transfer member 50 and the transfer paper 100. The corona charger 52 gives the toner image a true charge having the same polarity as the charge polarity of the toner particles forming the toner image, and is sufficient for good transfer to the transfer paper 100. Charge is applied to the toner image. The toner image is charged by the corona charger 52, and then transferred to the transfer paper 100 conveyed in the direction of the arrow from a paper supply unit (not shown) by a transfer bias from the transfer roller 80 (two). Next transfer). Thereafter, the transfer paper 100 onto which the toner image has been transferred is separated from the photoconductor 10 by a separation device (not shown), and after a fixing process is performed by a fixing device (not shown), the transfer paper 100 is discharged from the device. On the other hand, after the transfer, the untransferred toner is collected and removed by the cleaning device 60, and the residual charge is discharged by the discharging lamp 70 in preparation for the next charging.

As described above, the static friction coefficient of the intermediate transfer member is preferably 0.1 to 0.6, and more preferably 0.3 to 0.5. The volume resistance of the intermediate transfer member is preferably from several Ωcm to 10 ³ Ωcm. By setting the volume resistance to several Ωcm or more and 10 ³ Ωcm or less, the intermediate transfer member itself is prevented from being charged, and the charge imparted by the charge imparting means hardly remains on the intermediate transfer member. Transfer unevenness can be prevented. Further, it is possible to easily apply a transfer bias at the time of secondary transfer.

The material of the intermediate transfer member is not particularly limited, and all known materials can be used. An example is shown below.
(1) A material having a high Young's modulus (tensile modulus) is used as a single-layer belt. PC (polycarbonate), PVDF (polyvinylidene fluoride), PAT (polyalkylene terephthalate), PC (polycarbonate) / PAT ( Polyalkylene terephthalate) blend material, ETFE (ethylene tetrafluoroethylene copolymer) / PC, ETFE / PAT, PC / PAT blend material, carbon black dispersed thermosetting polyimide, or the like is used. These single-layer belts having a high Young's modulus have the advantage that the amount of deformation with respect to stress during image formation is small, and registration is not likely to occur particularly during color image formation.
(2) A belt having a two- or three-layer structure in which a belt having a high Young's modulus is used as a base layer and a surface layer or an intermediate layer is provided on the outer periphery thereof. Therefore, the line image has a performance capable of preventing the line image from being lost.
(3) Belts having a relatively low Young's modulus using rubber and elastomer, and these belts have an advantage that line images are hardly lost due to their softness. In addition, the width of the belt is made larger than that of the drive roll and the tension roll, and the elasticity of the belt ear protruding from the roll is used to prevent meandering, so that a low cost can be realized without the need for ribs or meandering prevention devices. .

  Conventionally, fluorine-based resin, polycarbonate resin, polyimide resin, and the like have been used as materials for the intermediate transfer belt. However, in recent years, an elastic belt in which the entire belt layer or a part of the belt is used as an elastic member has been used. ing. The transfer of a color image using a resin belt has the following problems.

  A color image is usually formed with four colored toners. On one color image, toner layers of 1 to 4 layers are formed. The toner layer receives pressure by passing through the primary transfer (transfer from the photoreceptor to the intermediate transfer belt) and the secondary transfer (transfer from the intermediate transfer belt to the sheet), and the cohesive force between the toners increases. When the cohesive force between the toners increases, the phenomenon of missing characters in the characters and missing edges in the solid portion image tends to occur. Since the resin belt has a high hardness and does not deform according to the toner layer, the toner layer is easily compressed, and the character dropout phenomenon is likely to occur.

  Recently, there is an increasing demand for forming full-color images on various papers, for example, Japanese paper, intentionally irregularities, and forming images on paper. However, a paper with poor smoothness is liable to generate toner and voids at the time of transfer, and transfer loss is likely to occur. When the transfer pressure at the secondary transfer portion is increased to improve the adhesion, the condensing power of the toner layer is increased, and the above-described character void is generated.

  The elastic belt is used for the following purposes. The elastic belt is deformed corresponding to the toner layer and the paper having poor smoothness at the transfer portion. In other words, since the elastic belt deforms following local irregularities, it is possible to obtain a good adhesion without excessively increasing the transfer pressure with respect to the toner layer, and a paper with poor flatness that has no void in characters. The transfer image with excellent uniformity can be obtained.

  The elastic belt resin is polycarbonate, fluorine resin (ETFE, PVDF), polystyrene, chloropolystyrene, poly-α-methylstyrene, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer. Polymer, styrene-maleic acid copolymer, styrene-acrylic acid ester copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-acrylic acid Octyl copolymer and styrene-phenyl acrylate copolymer), styrene-methacrylic acid ester copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-phenyl methacrylate copolymer) Coalesce etc.), styrene-α-chloroacryl Styrenic resin (monopolymer or copolymer containing styrene or styrene-substituted product), methyl methacrylate resin, butyl methacrylate resin, acrylic resin, such as methyl phosphate copolymer, styrene-acrylonitrile-acrylic acid ester copolymer Ethyl acid resin, butyl acrylate resin, modified acrylic resin (silicone modified acrylic resin, vinyl chloride resin modified acrylic resin, acrylic / urethane resin, etc.), vinyl chloride resin, styrene-vinyl acetate copolymer, vinyl chloride-vinyl acetate Polymer, rosin-modified maleic resin, phenol resin, epoxy resin, polyester resin, polyester polyurethane resin, polyethylene, polypropylene, polybutadiene, polyvinylidene chloride, ionomer resin, polyurethane resin, silicone resin, ketone resin, Len - ethyl acrylate copolymer, may be used xylene resin and polyvinyl butyral resin, polyamide resin, one kind or two kinds or more selected from the group consisting of modified polyphenylene oxide resin. However, it is a matter of course that the material is not limited to the above materials.

  Elastic rubber and elastomer include butyl rubber, fluorine rubber, acrylic rubber, EPDM, NBR, acrylonitrile-butadiene-styrene rubber natural rubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber, ethylene-propylene rubber, ethylene-propylene ter Polymer, chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, urethane rubber, syndiotactic 1,2-polybutadiene, epichlorohydrin rubber, silicone rubber, fluorine rubber, polysulfide rubber, polynorbornene rubber, hydrogenated nitrile Selected from the group consisting of rubber, thermoplastic elastomers (eg polystyrene, polyolefin, polyvinyl chloride, polyurethane, polyamide, polyurea, polyester, fluororesin) It is possible to use one kind or two or more kinds that. However, it is natural that the material is not limited to the above materials.

  There are no particular restrictions on the conductive agent for adjusting the resistance value. For example, carbon black, graphite, metal powder such as aluminum and nickel, tin oxide, titanium oxide, antimony oxide, indium oxide, potassium titanate, antimony oxide-tin oxide composite Conductive metal oxides such as oxide (ATO) and indium oxide-tin oxide composite oxide (ITO), and conductive metal oxides are coated with insulating fine particles such as barium sulfate, magnesium silicate, and calcium carbonate. But you can. Of course, the conductive agent is not limited to the above conductive agent.

  The surface layer material and the surface layer are required to prevent contamination of the photoconductor by the elastic material, reduce the surface friction resistance to the transfer belt surface, reduce the adhesion of the toner, and improve the cleaning property and the secondary transfer property. . For example, materials that use one or more of polyurethane, polyester, epoxy resin, etc. to reduce surface energy and increase lubricity, such as powders of fluororesins, fluorine compounds, fluorocarbons, titanium dioxide, silicon carbide, etc. Can be used by dispersing one or more kinds of particles, particles or particles having different particle sizes, and by forming a fluorine-rich layer on the surface by heat treatment like a fluorine-based rubber material, the surface energy can be increased. You can also use a smaller one

The method for manufacturing the belt is not limited, and the following method can be used.
Centrifugal molding method in which material is poured into a rotating cylindrical mold to form a belt Spray coating method in which a liquid paint is sprayed to form a film Dipping method in which a cylindrical mold is dipped in a solution of the material and pulled up Internal and external molds Casting method for pouring into a method A method in which a compound is wound around a cylindrical mold and vulcanized and polished. The invention is not limited to this, and a belt is generally manufactured by combining a plurality of manufacturing methods.

As a method for preventing the elastic belt from stretching, there are a method of forming a rubber layer in the core resin layer having a small elongation, a method of putting a material for preventing the elongation into the core layer, and the like.
Examples of the material constituting the core layer for preventing elongation include natural fibers such as cotton and silk, polyester fibers, nylon fibers, acrylic fibers, polyolefin fibers, polyvinyl alcohol fibers, polyvinyl chloride fibers, and polyvinylidene chloride fibers. 1 type selected from the group consisting of synthetic fibers such as polyurethane fiber, polyacetal fiber, polyfluoroethylene fiber and phenol fiber, inorganic fibers such as carbon fiber, glass fiber and boron fiber, and metal fibers such as iron fiber and copper fiber, or Two or more kinds can be used, and a woven or thread-like one can be used. Of course, the material is not limited to the above.

The yarn may be twisted in any manner, such as one or a plurality of filaments twisted, a single twisted yarn, various twisted yarns, a double yarn or the like. Further, for example, fibers of a material selected from the above material group may be blended. Of course, the yarn can be used after being subjected to an appropriate conductive treatment.
On the other hand, as the woven fabric, any woven fabric such as knitted fabric can be used. Of course, a cross-woven fabric can also be used, and naturally conductive treatment can be performed.

  The production method for providing the core layer is not particularly limited, for example, a method of providing a woven fabric woven in a cylindrical shape on a mold and the like, and providing a coating layer thereon, the woven fabric woven in a cylindrical shape is a liquid rubber And a method of providing a coating layer on one side or both sides of the core layer, and a method of winding a thread spirally around a mold at an arbitrary pitch and providing a coating layer thereon.

  The thickness of the elastic layer depends on the hardness of the elastic layer, but if it is too thick, the surface expands and contracts and cracks are likely to occur in the surface layer. In addition, it is not preferable that the thickness is too large because the amount of expansion and contraction is large and the image is stretched.

(Tandem type color image forming device)
The present invention can also be used as a tandem color image forming apparatus. An example of an embodiment of a tandem type color image forming apparatus will be described. As shown in FIG. 3, the tandem type electrophotographic apparatus includes a direct transfer system in which an image on each photoconductor 1 is sequentially transferred onto a sheet s conveyed by a sheet conveying belt 3 by a transfer apparatus 2; As shown in FIG. 4, the images on the respective photoconductors 1 are once sequentially transferred to the intermediate transfer member 4 by the primary transfer device 2, and then the images on the intermediate transfer member 4 are transferred to the sheet s by the secondary transfer device 5. There are indirect transfer systems that perform batch transfer. The transfer device 5 is a transfer conveyance belt, but there are also roller shapes and methods.

Comparing the direct transfer type and the indirect transfer type, the former arranges the sheet feeding device 6 on the upstream side of the tandem image forming apparatus T on which the photoconductors 1 are arranged, and the fixing device 7 on the downstream side. There is a drawback in that the size increases in the sheet conveying direction.
On the other hand, the latter can set the secondary transfer position relatively freely.
The sheet feeding device 6 and the fixing device 7 can be arranged so as to overlap with the tandem image forming apparatus T, and there is an advantage that downsizing is possible.

In the former, in order not to increase the size in the sheet conveying direction, the fixing device 7 is disposed close to the tandem type image forming apparatus T. For this reason, the fixing device 7 cannot be disposed with a sufficient margin that allows the sheet s to bend, and an impact when the leading edge of the sheet s enters the fixing device 7 (particularly with a thick sheet) or fixing. There is a drawback that the fixing device 7 tends to affect image formation on the upstream side due to the difference in speed between the sheet conveyance speed when passing through the apparatus 7 and the sheet conveyance speed by the transfer conveyance belt.
On the other hand, in the latter case, the fixing device 7 can be disposed with a sufficient margin that allows the sheet s to bend, so that the fixing device 7 can hardly affect the image formation.

In view of the above, recently, an indirect transfer type of tandem type electrophotographic apparatus has attracted attention.
In this type of color electrophotographic apparatus, as shown in FIG. 4, the transfer residual toner remaining on the photoreceptor 1 after the primary transfer is removed by the photoreceptor cleaning device 8 to clean the surface of the photoreceptor 1. In preparation for another image formation. Further, the transfer residual toner remaining on the intermediate transfer body 4 after the secondary transfer is removed by the intermediate transfer body cleaning device 9 to clean the surface of the intermediate transfer body 4 to prepare for image formation again.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 5 shows an embodiment of the present invention, which is a tandem indirect transfer type electrophotographic apparatus. In the figure, reference numeral 100 is a copying apparatus main body, 200 is a paper feed table on which the copying apparatus is placed, 300 is a scanner mounted on the copying apparatus main body 100, and 400 is an automatic document feeder (ADF) mounted thereon. The copying machine main body 100 is provided with an endless belt-shaped intermediate transfer member 10 at the center.
Then, as shown in FIG. 5, in the illustrated example, it is wound around three support rollers 14, 15, and 16 so that it can be rotated and conveyed clockwise in the figure.

In this illustrated example, an intermediate transfer body cleaning device 17 for removing residual toner remaining on the intermediate transfer body 10 after image transfer is provided on the left of the second support roller 15 among the three.
Further, among the three images, four images of yellow, cyan, magenta, and black are arranged on the intermediate transfer member 10 stretched between the first support roller 14 and the second support roller 15 along the conveyance direction. The tandem image forming apparatus 20 is configured by arranging the forming units 18 side by side.

  An exposure device 21 is further provided on the tandem image forming apparatus 20 as shown in FIG. On the other hand, a secondary transfer device 22 is provided on the side opposite to the tandem image forming apparatus 20 with the intermediate transfer body 10 interposed therebetween. In the illustrated example, the secondary transfer device 22 is configured by spanning a secondary transfer belt 24, which is an endless belt, between two rollers 23, and is pressed against the third support roller 16 via the intermediate transfer body 10. The image on the intermediate transfer body 10 is transferred to a sheet.

A fixing device 25 for fixing the transfer image on the sheet is provided beside the secondary transfer device 22. The fixing device 25 is configured by pressing a pressure roller 27 against a fixing belt 26 that is an endless belt.
The secondary transfer device 22 described above is also provided with a sheet transport function for transporting the image-transferred sheet to the fixing device 25. Of course, a transfer roller or a non-contact charger may be arranged as the secondary transfer device 22, and in such a case, it is difficult to provide this sheet conveying function together.
In the illustrated example, under such a secondary transfer device 22 and a fixing device 25, a sheet reversing device 28 for reversing the sheet so as to record images on both sides of the sheet in parallel with the tandem image forming device 20 described above. Is provided.

  Now, when making a copy using this color electrophotographic apparatus, a document is set on the document table 30 of the automatic document feeder 400. Alternatively, the automatic document feeder 400 is opened, a document is set on the contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed and pressed by it.

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 other contact glass 32. At that time, the scanner 300 is immediately driven to travel the first traveling body 33 and the second traveling body 34. Then, the first traveling body 33 emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body 34, and is reflected by the mirror of the second traveling body 34 and passes through the imaging lens 35. The document is placed in the reading sensor 36 and the original content is read.
When a start switch (not shown) is pressed, one of the support rollers 14, 15, and 16 is driven to rotate by a drive motor (not shown), and the other two support rollers are driven to rotate to convey the intermediate transfer member 10. To do. At the same time, the individual image forming means 18 rotates the photoconductor 40 to form black, yellow, magenta, and cyan monochrome images on each photoconductor 40. Then, along with the conveyance of the intermediate transfer member 10, the single color images are sequentially transferred to form a composite color image on the intermediate transfer member 10.

On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers 42 of the paper feed table 200 is selectively rotated, and the sheet is fed out from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43, and the separation roller 45. Then, the sheets are separated one by one into the paper feed path 46, transported by the transport roller 47, guided to the paper feed path 48 in the copying machine main body 100, and abutted against the registration roller 49 and stopped.
Alternatively, the sheet feed roller 50 is rotated to feed out the sheets on the manual feed tray 51, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped.
Then, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer body 10, the sheet is fed between the intermediate transfer body 10 and the secondary transfer device 22, and transferred by the secondary transfer device 22. A color image is recorded on the sheet.

  The image-transferred sheet is conveyed by the secondary transfer device 22 and sent to the fixing device 25. The fixing device 25 applies heat and pressure to fix the transferred image, and then the switching roller 55 is used to switch the discharge roller. The paper is discharged at 56 and stacked on the paper discharge tray 57. Alternatively, it is switched by the switching claw 55 and put into the sheet reversing device 28, where it is reversed and guided again to the transfer position, and an image is recorded also on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56.

On the other hand, the intermediate transfer body 10 after the image transfer is removed by the intermediate transfer body cleaning device 17 to remove residual toner remaining on the intermediate transfer body 10 after the image transfer, so that the tandem image forming apparatus 20 can prepare for another image formation.
Here, the registration roller 49 is generally used while being grounded, but it is also possible to apply a bias for removing paper dust from the sheet.
Now, in the tandem image forming apparatus 20 described above, the individual image forming means 18 includes, for example, a charging device 60, a developing device 61, and a primary device around a drum-shaped photoconductor 40 as shown in FIG. The image forming apparatus includes a transfer device 62, a photoconductor cleaning device 63, a charge removal device 64, and the like.

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

[Production example]
<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), 166 parts of methacrylic acid, 110 butyl acrylate Parts and 1 part of ammonium persulfate were added and stirred at 3800 rpm for 30 minutes to obtain a white emulsion. The system was heated to raise the system temperature to 75 ° C. and reacted for 4 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 6 hours, and an aqueous dispersion of vinyl resin (methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt copolymer). [Fine particle dispersion 1] was obtained. The volume average particle diameter of [fine particle dispersion 1] measured by LA-920 was 110 nm. A portion of [Fine Particle Dispersion 1] was dried to isolate the resin component. The Tg of the resin was 58 ° C., and the weight average molecular weight was 130,000.

<Adjustment of aqueous phase>
990 parts of water, 83 parts of [fine particle dispersion 1], 37 parts of a 48.3% aqueous solution of dodecyl diphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred. A milky white liquid was obtained. This is designated as [Aqueous Phase 1].

<Synthesis of low molecular weight polyester>
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 Add 2 parts of tin oxide, react at 230 ° C for 7 hours at normal pressure, and further react for 5 hours under reduced pressure of 10-15 mmHg, then add 44 parts of trimellitic anhydride to the reaction vessel at 180 ° C at normal pressure. By reacting for 3 hours, [low molecular weight polyester 1] was obtained. [Low molecular polyester 1] had a number average molecular weight of 2,300, a weight average molecular weight of 6,700, a Tg of 43 ° C., and an acid value of 25.

<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 Part and 2 parts of dibutyltin oxide were added, reacted at 230 ° C. at normal pressure for 7 hours, 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 2200, a weight average molecular weight of 9700, Tg of 54 ° C., an acid value of 0.5, and a hydroxyl value of 52.
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. [Prepolymer 1] had a free isocyanate weight% of 1.53%.

<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 4 and a half hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 417.

<Synthesis of master batch (MB)>
Add 300 parts of methyl ethyl ketone, 500 parts of yellow pigment represented by the above chemical formula (1), and 500 parts of polyester resin, mix with a Henschel mixer (made by Mitsui Mining Co., Ltd.), and use the two rolls at 110 ° C. for 1 hour. After kneading, rolling and cooling and pulverization with a pulverizer gave a master batch. Masterbatches 1 to 6 were prepared using pigments (CI Pigment Yellow 155) having different particle diameters.

[Example 1]
<Production of oil phase>
In a container equipped with a stirring bar and a thermometer, 378 parts of [Low molecular weight polyester 1], Carnauba WAX10O part, 947 parts of ethyl acetate were charged, heated to 80 ° C. with stirring, and kept at 80 ° C. for 5 hours. It was cooled to 30 ° C at 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Raw material solution 1] 1324 parts are transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads are 80% by volume. Carbon black and WAX were dispersed under conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [low molecular weight polyester 1] was added, followed by two passes with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1]. The solid content concentration of [Pigment / WAX Dispersion 1] (130 ° C., 30 minutes) was 50%.

<Emulsification => Solvent removal>
[Pigment / WAX Dispersion 1] 749 parts, [Prepolymer 1] 115 parts, [Ketimine Compound 1] 2.9 parts in a container and TK homomixer (manufactured by Tokushu Kika) at 5,000 rpm for 2 minutes After mixing, 1200 parts of [Aqueous phase 1] was added to the container, and mixed with a TK homomixer at 13,000 rpm for 25 minutes to obtain [Emulsion slurry 1].
[Emulsion slurry 1] was charged into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 40 ° C. for 24 hours to obtain [Dispersion slurry 1].

<Charging control>
After 100 parts of the dispersion slurry 1 is solid-liquid separated by centrifugation, 100 parts of clean ion-exchanged water is added again, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then centrifuged again. Was repeated three times. Thereafter, a methanol solution (5 wt% solution) of a fluorinated quaternary ammonium salt compound represented by the following chemical formula (2) corresponding to 0.1 wt% with respect to the solid content of the toner was added and stirred for 10 minutes. As a result, the fluorine-based quaternary ammonium salt was adsorbed on the particle surface, and charge control was performed.

<Washing->Drying>
[Dispersion Slurry 1] 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 (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(2) 1OO parts of 10% aqueous sodium hydroxide solution was added to the filter cake obtained in (1) above, 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 obtained in (2) above, mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(4) Add 300 parts of ion-exchanged water to the filter cake obtained in (3) above, mix with a TK homomixer (10 minutes at 12,000 rpm) and then filter twice [Filter cake 1] Got.
[Filter cake 1] was dried at 45 ° C. for 48 hours in a circulating dryer. Thereafter, sieved with a mesh of 75 μm, [Toner Base Particle 1] was obtained.
Thereafter, 100 parts of [toner base particle 1] and 1 part of hydrophobized silica were mixed with a Henschel mixer to obtain a toner. The evaluation results are shown in Table 1.

(Carrier production)
・ Core material Mn ferrite particles (weight average diameter: 35 μm) 5000 parts ・ Coating material Toluene 450 parts Silicone resin SR2400 450 parts (Toray, Dow Corning, silicone, nonvolatile content 50%)
Aminosilane SH6020 10 parts (made by Toray Dow Corning Silicone)
10 parts of carbon black

  The coating material is dispersed with a stirrer for 10 minutes to prepare a coating solution, and the coating solution and the core material are coated in a fluidized bed while forming a swirling flow with a rotating bottom plate disk and stirring blades. The coating solution was applied on the core material. The obtained coated material was baked in an electric furnace at 250 ° C. for 2 hours to obtain the carrier.

(Evaluation of two-component developer)
When evaluating an image with a two-component developer, a ferrite carrier having an average particle diameter of 35 μm coated with a silicone resin at an average thickness of 0.5 μm is used as follows, and toner 7 of each color is used with respect to 100 parts by weight of the carrier. A developer was prepared by uniformly mixing and charging parts by weight using a tumbler mixer of a type in which the container was rolled and stirred.

[Examples 2 to 4]
Toner 2 (Example 2), Toner 3 (Example 3), Toner 4 (Example 4) are the same as Example 1 except that master batch 1 used in Example 1 is replaced with master batches 2 to 4. )

[Comparative Examples 1 and 2]
Toner 5 (Comparative Example 1) and Toner 6 (Comparative Example 2) were obtained in the same manner as in Example 1 except that master batch 1 used in Example 1 was replaced with master batches 5 and 6.

  Table 2 shows the average circularity, circularity SF-1, and circularity SF-2 of toners 1 to 6 obtained above.

[Toner Evaluation Items]
1) Image Density Ricoh's imgio Neo 450 was modified to use a belt fixing system, with a low adhesion amount of 0.3 ± 0.1 mg / cm ^{2 on} plain paper transfer paper (Ricoh Type 6200). After outputting the solid image, the image density was measured by X-Rite (manufactured by X-Rite). An image density of 1.4 or higher was evaluated as ◯, and an image density lower than that as X.

2) Fixability (hot offset resistance, low temperature fixability)
A belt fixing method by remodeling Ricoh's imgio Neo 450, which is 1.0 ± 0.1 mg as a solid image on plain paper and cardboard transfer paper (Ricoh type 6200 and NBS Ricoh's copy printing paper <135>). The fixing was evaluated with a toner adhesion amount of / cm ² . The fixing test was conducted by changing the temperature of the fixing belt, and the upper limit temperature at which hot offset did not occur on plain paper was defined as the upper limit temperature for fixing. Further, the minimum fixing temperature was measured with a thick paper. The lower limit fixing temperature was determined as the fixing lower limit temperature at the fixing roll temperature at which the residual ratio of the image density after rubbing the obtained fixed image with a pad was 70% or more. It is desirable that the fixing upper limit temperature is 200 ° C. or higher and the fixing lower limit temperature is 140 ° C. or lower.

3) Cleanability The remaining toner on the photoreceptor after passing through the cleaning process after outputting a 95% chart with an image area ratio of 95% is transferred to a white paper with Scotch tape (manufactured by Sumitomo 3M Co., Ltd.). Measured with RD514 type, ◎ if the difference from the blank is less than 0.005, ○ if 0.005 to 0.010, Δ if 0.011 to 0.02, and more than 0.02. Was evaluated as x.

4) After transferring the 20% transferable image area ratio chart from the photoconductor to paper, the transfer residual toner on the photoconductor immediately before cleaning is transferred to white paper with Scotch tape (manufactured by Sumitomo 3M Ltd.), and it is reflected by Macbeth reflection. Measured with a densitometer RD514 type, ◎ if the difference from the blank is less than 0.005, ○ if 0.005 to 0.010, △ if 0.011 to 0.02, and 0.02. Those exceeding were evaluated as x.

5) Charging stability Using an evaluation machine in which Ricoh's IPSiO Color 8100 was remodeled into an oil-less fixing system and tuned, an image area ratio 5% chart continuous 100,000 sheet output durability test was carried out. Changes in charge amount were evaluated. 1 g of developer was weighed and the change in charge amount was determined by the blow-off method. When the change in the charge amount was 5 μc / g or less, it was evaluated as ◯, when it was 10 μc / g or less, Δ when it exceeded 10 μc / g.

6) Image graininess and sharpness Using an evaluation machine that was tuned by remodeling Ricoh's IPSiO Color 8100 into an oilless fixing system, a photographic image was output in a single color, and the degree of graininess and sharpness was evaluated visually. . Evaluations were made from GOOD, ◎, ○, Δ, and ×.並 is equivalent to offset printing, ◯ is slightly worse than offset printing, Δ is much worse than offset printing, and × is very bad compared to conventional electrophotographic images.

7) Transparency A monochromatic solid image was output to an OHP sheet using an evaluation machine that was tuned by remodeling the IPSiO Color 8100 made by Ricoh into an oilless fixing system so that the adhesion amount was 0.4 mg / cm 2. The color development of the OHP projection image was visually evaluated. Evaluations were made from GOOD, ◎, ○, Δ, and ×. ◎ is completely transparent and good color development, ○ indicates color development but slight turbidity, Δ indicates clear turbidity, × indicates slight color development and no drop.

8) Fog In an environment with a temperature of 10 ° C and a humidity of 15%, using an evaluation machine that has been tuned by remodeling the Ricoh IPSiO Color 8100 into an oil-less fixing system, output 100000 images in a continuous 5% chart using each toner. The degree of toner contamination on the transfer paper upper surface after the durability test was visually evaluated (loupe). Evaluations were made from GOOD, ◎, ○, Δ, and ×. ◎ indicates that the toner stains are not observed at all and is in a good state, ○ indicates that only slight stains are observed, △ indicates that the stains are slightly observed, and × indicates that the contamination is not within the allowable range. There is a problem with dirt.

9) Toner scattering In an environment with a temperature of 40 ° C. and a humidity of 90%, using an evaluation machine that was tuned by remodeling Ricoh's IPSiO Color 8100 into an oil-less fixing system, an image area ratio 5% chart continuous 100,000 sheets using each toner The toner contamination state in the copying machine after the output durability test was visually evaluated. ◎ indicates that the toner stains are not observed at all and is in a good state, ○ indicates that only slight stains are observed, △ indicates that the stains are slightly observed, and × indicates that the contamination is not within the allowable range. There is a problem with dirt.

  The electrostatic charge image developing toner of the present invention does not have excessive pigment uneven distribution on the toner surface, and it is possible to obtain image quality with sufficient image density while ensuring developability, transferability, and fixability. It is suitable as an electrostatic charge image developing toner used in an electrophotographic apparatus or an electrostatic recording apparatus.

1 is a schematic configuration diagram of an image forming apparatus of the present invention. 1 is a schematic configuration diagram of an image forming apparatus of the present invention. 1 is a diagram illustrating an example in which an image forming apparatus of the present invention is a tandem color image forming apparatus. FIG. 2 is a diagram illustrating an example of a case where the image forming apparatus of the present invention is a tandem indirect transfer type color image forming apparatus using an intermediate transfer member. 1 is a diagram illustrating an example in which an image forming apparatus of the present invention is incorporated into an electrophotographic apparatus as a tandem indirect transfer type color image forming apparatus. 1 is a diagram illustrating an example in which an image forming apparatus of the present invention is a tandem color image forming apparatus.

Explanation of symbols

(Fig. 1, Fig. 2)
DESCRIPTION OF SYMBOLS 10 Photosensitive drum 20 Charging roller 30 Exposure apparatus 40 Developing apparatus 41 Developing belt 42 Developing tank 43 Pumping roller 44 Coating roller 45 Developing unit 50 Intermediate transfer body 51 Suspension roller 52 Corona charger 60 Cleaning device 70 Static elimination lamp 80 Transfer roller 90 Cleaning Device 100 Transfer paper (Figs. 3 and 4)
DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Transfer apparatus 3 Sheet conveyance belt s Sheet 2 Primary transfer apparatus 4 Intermediate transfer body 5 Secondary transfer apparatus T Tandem type image forming apparatus 6 Paper feed apparatus 7 Fixing apparatus 8 Photoconductor cleaning apparatus 9 Intermediate transfer body cleaning apparatus (Fig. 5)
DESCRIPTION OF SYMBOLS 10 Intermediate transfer body 14,15,16 Support roller 17 Intermediate transfer body cleaning apparatus 18 Image forming means 20 Tandem image forming apparatus 21 Exposure apparatus 22 Secondary transfer apparatus 23 Roller 24 Secondary transfer belt 25 Fixing apparatus 26 Fixing belt 27 Pressure Roller 28 Sheet reversing device 30 Document table 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 42 Paper feed roller 43 Paper bank 44 Paper feed cassette 45 Separating roller 46 Paper feed path 47 Transport roller 48 Paper feed path 49 Registration Roller 50 Paper Feeding Roller 51 Manual Tray 52 Separation Roller 53 Manual Feeding Path 55 Switching Claw 56 Ejection Roller 57 Paper Ejection Tray 100 Copier Main Body 200 Paper Feed Table 300 Scanner 400 Automatic Document Feeder (ADF)
(Fig. 6)
40 Photoconductor 60 Charging device 61 Developing device 62 Primary transfer device 63 Photoconductor cleaning device 64 Static eliminating device

Claims (12)

A toner comprising base particles produced by dispersing oil droplets of an organic solvent in which a toner composition including a master batch containing at least a colorant and a binder resin is dissolved or dispersed in an aqueous medium , and at least the binder includes a polyester resin as a resin, coloring agent, Ri Do two kinds, the mixing ratio of the colorant (1) and the colorant (2) the weight of the following colorant (1) and a colorant (2) A toner for developing an electrostatic charge image, wherein the toner has a ratio of 10:90 to 60:40 .
Colorant (1): Organic pigment represented by the following chemical formula (1) having a primary particle diameter (50% diameter) of 0.08 to 0.12 μm Colorant (2): Primary particle diameter (50% diameter) Organic pigment represented by the following chemical formula (1) of 01 to 0.06 μm

The toner for developing an electrostatic charge image according to claim 1, comprising a fluorine-based quaternary ammonium salt compound as a charge control agent on the surface of the base particle .   The electrostatic image developing toner according to claim 1, wherein the toner contains at least a modified polyester resin as a binder resin.   4. The electrostatic image developing toner according to claim 1, wherein the toner particles have an average circularity E of 0.90 to 0.99.   The electrostatic charge image developing according to any one of claims 1 to 4, wherein the toner particles have a circularity SF-1 value of 100 to 150 and a circularity SF-2 value of 100 to 140. toner.   6. The volume average particle diameter Dv of the toner particles is 2 to 7 μm, and the ratio Dv / Dn of the volume average particle diameter Dv to the number average particle diameter Dn is 1.25 or less. The toner for developing an electrostatic image according to any one of the above. The yellow for electrostatic image development according to any one of claims 1 to 6, wherein the mixing ratio of the colorant (1) and the colorant (2) is 30:70 to 60:40 by weight ratio. toner.   The toner is composed of particles formed by dispersing an oil droplet of an organic solvent in which a toner composition containing a prepolymer is dissolved in an aqueous medium, and by an extension reaction and / or a crosslinking reaction. The toner for developing an electrostatic image according to any one of the above. Developer of a two-component system which comprises a carrier consisting of at least claims 1-8 or electrostatic image developing toner and the magnetic particles described. In a process cartridge that integrally supports at least one member selected from a photosensitive member, 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 holds toner. A process cartridge, wherein the toner is an electrostatic image developing toner according to any one of claims 1 to 8 . The electrostatic image on the electrostatic image bearing member is developed with a developer for developing an electrostatic image to form a toner image, and a transfer means is brought into contact with the surface of the electrostatic image bearing member via a transfer material so that the toner image is An image forming apparatus for electrostatic transfer to a transfer material, wherein the developer is the two-component developer according to claim 9 . An image forming method comprising forming an image using the image forming apparatus according to claim 11 .

Images