JP4221319B2 - Electrophotographic toner and image forming process - Google Patents

Description

  The present invention relates to a toner used as a developer for developing an electrostatic charge image in electrophotography, electrostatic recording, electrostatic printing, etc., a developer containing the toner, and an image formation using the developer. The present invention relates to a method and an image forming apparatus. More specifically, a toner for developing an electrostatic image used in a copying machine, a laser printer, a plain paper fax machine, or the like using a direct or indirect electrophotographic developing system, a developer containing the toner, and an image formation using the developer The present invention relates to a method and an image forming apparatus. Further, a toner for developing an electrostatic image used in a full-color copying machine, a full-color laser printer, a full-color plain paper fax machine using a direct or indirect electrophotographic multicolor developing system, a developer containing the toner, and using the developer The present invention relates to an image forming method and an image forming apparatus.

In the developing process, a developer used in electrophotography, electrostatic recording, electrostatic printing, and the like is once attached to an image carrier such as a photoreceptor on which an electrostatic charge image is formed, and then transferred to a transfer process. After being transferred from the photoconductor to a transfer medium such as transfer paper, the toner is fixed on the paper surface in a fixing step. At that time, as a developer for developing an electrostatic charge image formed on the latent image holding surface, a two-component developer composed of a carrier and a toner, and a one-component developer not requiring a carrier (magnetic toner, Non-magnetic toners are known.
Conventionally, as dry toners used for electrophotography, electrostatic recording, electrostatic printing, and the like, toner binders such as styrene resins and polyesters are melt kneaded and finely pulverized together with colorants and the like.

In order to obtain high-quality and high-quality images, improvements have been made by reducing the particle size of the toner. Even after passing, the ultrafine particles have a defect that they have strong adhesive force and remain attached to the toner having a target particle size and cannot be classified. Inside the machine, such ultrafine particles may be agitated with the carrier in the developing section, or when used as a one-component developer, due to contact stress caused by the developing roller and toner supply roller, layer thickness regulating blade, friction charging blade, etc. There has been a phenomenon that image quality is deteriorated because it adheres to or adheres to a carrier or a machine part, and a fluidizing agent is embedded in the toner surface. Further, due to its shape, the fluidity as powder is poor, a large amount of fluidizing agent is required, and the filling rate into the toner bottle is low, which is an obstacle to downsizing. Therefore, the current situation is that the merit of reducing the particle size is not utilized. In addition, the pulverization method has a particle size limit and cannot cope with further reduction in particle size.
Further, in order to stabilize various characteristics such as toner chargeability, a means for sharpening the particle size distribution of the toner is used, but when the average particle size of the toner does not match the specific particle size distribution. Does not provide a sufficient effect. In other words, it is not sufficient to make a general rule about the relationship between the average particle size and the particle size distribution, and there are specific particle size distributions and shapes according to the average particle size of each toner.

Furthermore, in order to create full-color images, the process of transferring images formed from multicolor toners from the photoreceptor to transfer media and paper has become complicated, and transferability due to irregular shapes such as pulverized toner Due to the poorness of the image, problems such as omission of the transferred image and a large amount of toner consumption have occurred.
However, the spherical toner cannot be removed by an apparatus (for example, a cleaning blade or a cleaning brush) for removing the toner remaining on the photosensitive member or the transfer medium, and cleaning failure occurs. In addition, the toner surface is exposed to the outside in all directions due to its spherical shape, and is easily exposed to contact with a charging member such as a carrier or a charging blade. There is a problem in durability such that the control agent is easily embedded in the toner surface and the fluidity of the toner is immediately reduced.

Therefore, there is an increasing demand for further improving transfer efficiency to reduce toner consumption to obtain a high-quality image with no missing images and to reduce running costs. If the transfer efficiency is very good, there is no need for a cleaning unit for removing untransferred toner from the photoconductor or transfer medium, and there is an advantage that the apparatus can be reduced in size and cost and waste toner is eliminated. Because. Various spherical toner manufacturing methods have been devised to compensate for the disadvantages of such irregular shape effects.
In the toner production method by suspension polymerization, only spherical or nearly spherical toner can be produced, and it is easily sheared when suspended and dispersed in water. The problem of sticking to is not solved. On the other hand, in the toner manufacturing method by emulsion polymerization, it is possible to manufacture from an irregular shaped toner to a spherical shape, but it is necessary to adjust the shape by heating in the post-treatment, and in addition, aggregation in water and ultrafine powder that did not aggregate during association remain. The problem of carrier contamination and sticking to mechanical parts due to such fine particles has not been solved.

As a method for solving these problems, Patent Document 1 discloses a construction method involving volume shrinkage called a polymer dissolution suspension method.
In this method, a toner raw material is dispersed and dissolved in a volatile solvent such as a low-boiling organic solvent, and this is emulsified and formed into droplets in an aqueous medium containing a dispersant, and then the volatile solvent is removed.
However, when the volatile solvent is removed, the volume of the droplets shrinks. However, when a solid fine particle dispersant that does not dissolve in an aqueous medium is selected as the dispersant, only amorphous particles can be obtained. Further, when the solid content in the solvent was increased in order to increase productivity, the viscosity of the dispersed phase increased, and the resulting particles had a large particle size and a broad distribution. On the other hand, when the molecular weight of the resin used is reduced to lower the viscosity of the dispersed phase, the fixability (particularly hot offset resistance) must be sacrificed.

On the other hand, in Patent Document 2, the resin used in the polymer dissolution suspension method has a low molecular weight to lower the viscosity of the dispersed phase, to facilitate emulsification, and to improve the fixing property by carrying out a polymerization reaction in the particles. . However, it does not improve the transferability and cleaning properties by adjusting the shape of the particles.
In addition, since it is sheared irregularly when suspended in water, ultrafine powder is easily generated, and the problem of sticking to carriers and machine parts has not been solved.
Also, these dry toners are developed and transferred onto paper or the like, and then fixed by heating and melting using a hot roll. At that time, if the hot roll temperature is too high, there will be a problem that the toner is excessively melted and fused to the hot roll (hot offset). If the hot roll temperature is too low, the toner will not melt sufficiently and fixing will be insufficient. Problem arises.

On the other hand, from the viewpoint of energy saving and downsizing of the apparatus, a toner having a higher hot offset generation temperature (hot offset resistance) and a lower fixing temperature (low temperature fixing property) is required. In addition, heat storage stability is required so that the toner is not blocked during storage and at ambient temperature in the apparatus. In particular, full-color copying machines and full-color printers require glossiness and color mixing of their images, so the toner must have a lower melt viscosity and a sharp-melt polyester toner binder is used. However, since such toner tends to cause hot offset, conventionally, in a full-color device, silicone oil or the like is applied to a heat roll.
However, the method of applying silicone oil to the hot roll requires an oil tank and an oil application device, and the device becomes complicated and large. Moreover, it causes deterioration of the heat roll and requires maintenance every certain period. Furthermore, the adhesion of oil to copy paper, OHP (overhead projector) film, etc. is unavoidable. In particular, OHP has a problem of deterioration of color tone due to the adhered oil.

JP-A-7-152202 JP-A-11-149179

The present invention is excellent in powder flowability, development, and transferability when a small toner particle is used, and can provide high image quality, and can prevent internal contamination due to melting of the toner fusion product in the fixing unit. Another object of the present invention is to provide a toner for developing an electrostatic charge image that can form an image with good and stable developability and high image quality even after long-term use, and a toner for developing an electrostatic charge image that has a long life as a toner.
Another object of the present invention is to provide a toner container filled with the toner, a developer containing the toner, an image forming method using the developer, and an image forming apparatus loaded with the developer.

As a result of intensive studies, the present inventors have specific thermal characteristics, specific particle size distribution, and specific circularity, and achieve the above object by adding and mixing external additives at a specific ratio. As a result, the present invention has been completed.
That is, the above-described problems are solved by the following inventions 1) to 12 ).
1) The modified polyester resin (i) as a toner binder resin A toner for including electrostatic image development, 15 minutes the toner at 130 ° C. using a Laboplastomill, obtained by melt-kneading at 50rpm rotational speed The elevated flow tester of the obtained toner melt-kneaded product has a 1/2 outflow temperature of 105 to 120 ° C., a volume average particle diameter (Dv) of 3 to 7 μm, a volume average particle diameter (Dv) and a number average particle diameter ( Dn) ratio (Dv / Dn) is 1.01 to 1.25, toner particles having a particle diameter of 2 to 4 μm are less than 10% by number and / or toner particles having a particle diameter of 8 μm or more are less than 2% by volume. The external additive is added and mixed at a ratio of 0.3 to 5.0 parts by weight with respect to 100 parts by weight of the base toner having an average circularity of 0.93 to 0.99. Toner for charge image development.
2) The toner for developing an electrostatic charge image according to 1), wherein a shape factor SF-1 of the toner is 105 to 170.
3) The electrostatic image developing toner according to 1) or 2), wherein the modified polyester resin (i) has a urea group.
4) The electrostatic image developing toner according to any one of 1) to 3), wherein the external additive is silica that has been subjected to a hydrophobic treatment.
5 ) The toner binder resin contains an unmodified polyester resin (LL) together with the modified polyester resin (i), and the weight ratio [(i) / (LL)] of (i) and (LL) is 5 / The electrostatic charge image developing toner according to any one of 1) to 4 ), wherein the toner is 95 to 80/20.
6 ) The electrostatic image developing toner according to 5 ), wherein the unmodified polyester resin (LL) has a peak molecular weight of 1000 to 20000.
7 ) The toner for developing an electrostatic charge image according to any one of 1) to 6 ), wherein a charge control substance is fixed on the particle surface of the base toner.
8 ) The electrostatic charge image according to any one of 1) to 7 ), wherein the electrostatic charge image is obtained by volume shrinkage at a shrinkage of 10 to 90% in an aqueous medium using a solid fine particle dispersant. Developing toner.
9 ) A toner container filled with the electrostatic image developing toner according to any one of 1) to 8 ).
10 ) A developer comprising the electrostatic image developing toner according to any one of 1) to 8 ).
11 ) An image forming method using the developer described in 10 ).
12 ) An image forming apparatus loaded with the developer described in 10 ).

Hereinafter, the present invention will be described in detail.
The present invention comprises (a) a modified polyester resin (i), (b) a 1/2 flow-out temperature of an elevated flow tester of a toner melt-kneaded product is 105 to 120 ° C., and (c) a volume average particle size of toner. diameter (Dv) is 3 to 7 [mu] m, the ratio of (d) the number average particle diameter (Dn) (Dv / Dn) is 1.01 to 1.25, toner particles having a particle size of (e) 2-4 [mu] m Less than 10% by volume and / or less than 2% by volume of toner particles having a particle diameter of 8 μm or more, and (f) 100 parts by weight of the base toner having an average circularity of 0.93 to 0.99. (G) By using a toner in which an external additive is added and mixed in a ratio of 0.3 to 5.0 parts by weight (that is, a toner having the above seven constituents), the toner fusion product in the fixing unit Can prevent in-machine contamination due to melting In other words, even if the toner balance for a long period of time is performed, the variation in the particle size of the toner in the developer is reduced, and good and stable developability can be obtained even with long-term stirring in the developing device. Even when used as a one-component developer, even if the balance of the toner is performed, the fluctuation of the toner particle size is reduced, and the toner is filmed on the developing roller and the toner is thinned. The toner is not fused to a member such as a blade, and good and stable developability and an image can be obtained even when the developing device is used (stirred) for a long time.

  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. When the volume average particle diameter of the toner is smaller than 3 μm, when used as a 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 lowered. However, when used as a one-component developer, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur. In particular, if the quantity balance of the ultra fine powder in the toner is poor, the toner fuses to the surface of the carrier, the filming of the toner on the developing roller, and the blade or other member for thinning the toner. Phenomenon such as toner fusing.

On the other hand, if the volume average particle size of the toner is larger than 7 μm, it becomes difficult to obtain a high-resolution and high-quality image, and the toner particle size is reduced when the toner in the developer is balanced. In many cases, the fluctuation becomes large. It was also clarified that the same applies when the volume average particle diameter (Dv) / number average particle diameter (Dn) is larger than 1.25.
In addition, it is difficult to solve these problems only by sharpening the particle size distribution of the toner, and the content rate of fine powder and / or the content rate of coarse powder is in a certain range as in the above (e). Furthermore, the problem can be solved only by setting the average circularity of the toner within a certain range as described later.

In general, a toner raw material composition containing a prepolymer is dissolved or dispersed in an organic solvent, and further is dispersed in an aqueous medium to produce a modified polyester resin (i) to obtain a toner. The core-shell structure is formed, the toner is melted and kneaded by the shearing force between the heating roller and the backup roller in the fixing unit, and the inside of the fixing unit is contaminated with the molten toner by exposing the low softening core resin to the surface. It became clear that it was offset on the transfer paper. In order to avoid this problem, it is preferable to set the 1/2 outflow temperature of the elevated flow tester of the toner melt-kneaded product to 105 to 120 ° C. When the temperature is lower than 105 ° C., the low-viscosity toner melted into the fixing unit may flow out and offset onto the transfer paper. When the temperature is higher than 120 ° C., it is confirmed that the toner is cold offset. In addition, these problems are difficult to solve simply by the thermal characteristics of the toner, and the melted and kneaded state in the fixing unit can be reproduced by melting and kneading the toner once. Is possible. Therefore, the toner melt-kneaded product as used in the present invention is a toner in a melt-kneaded state in order to reproduce the melt-kneaded state in the fixing unit.

In general, when the shape of the toner is close to a sphere, the transferability is improved, but the cleaning performance of the toner remaining on the photoreceptor without being transferred tends to deteriorate. Further, as a result of examining the shape and developability of the toner, the development stability and the background fogging with respect to the problem of the present invention, in addition to the factor of the toner particle size, the average circularity of the toner is 0.93 to 0.3. 99 is preferred. If it is smaller than 0.93, the initial development efficiency may be lowered. If it is larger than 0.99, the development efficiency tends to be greatly lowered at the time of long-term use although the development efficiency is initially high. It was confirmed that there was. Similarly, the shape factor SF-1 of the toner is particularly preferably from 105 to 170. If it is larger than 170, the toner is pulverized due to agitation in the developing device for a long period of time, so that the development stability and margin for background fogging are reduced. In some cases, the transfer efficiency of the toner to the toner is reduced. On the other hand, if the particle size is smaller than 105, external additives such as silica, which are coated on the toner particle surface for the purpose of improving the fluidity of the toner by agitation in the developing device for a long time, are embedded in the toner particle surface. The fluidity and chargeability of the toner may change, and the development stability and margin for background fogging may decrease. In addition, the cleaning property of toner remaining on the photosensitive member without being transferred may be deteriorated.
Here, the toner shape factor SF-1 indicates the degree of roundness of the toner particles, and is calculated by the following equation. This is a value obtained by dividing the square of the maximum length MXLNG of the figure formed by projecting the toner onto the two-dimensional plane by the area AREA of the figure and multiplying by 100π / 4.
When the value of SF-1 is 100, the shape of the toner is a true sphere, and becomes larger as the value of SF-1 increases.
SF-1 = {(MXLNG) ² / AREA} × (100π / 4)

In particular, in the present invention, in order to give an appropriate shape, it is important to use a solid fine particle dispersant in a production method having a volume shrinkage step with a volume shrinkage of 10 to 90% in an aqueous medium. If the volume shrinkage is outside the range of 10 to 90%, the toner particle shape becomes indefinite, which is not preferable. Moreover, a more preferable range is 30 to 70%.
Here, the volume shrinkage is Vo, the volume of the oil phase (dispersed phase) in which the toner raw material composition before being emulsified and dispersed in the aqueous medium is Vo, and the volume of the dispersed phase after emulsifying and dispersing to remove volatile components. Vt is expressed as volume shrinkage rate = (1−Vt / Vo) × 100, and the change in characteristics before emulsification and after being emulsified and dispersed is measured.
Specifically, it can be determined by the following method.
(A) Method of measuring weight and true specific gravity of oil phase and resulting toner before emulsification (b) Measure the average particle size of droplets after emulsification and dispersion in an aqueous medium and particles from which volatile components have been removed. , Volume conversion method

(External additive)
In addition, it is important in terms of developability and transferability that an external additive is added and mixed at a ratio of 0.3 to 5.0 parts by weight with respect to 100 parts by weight of the base toner. If it is less than 0.3 part by weight, the fluidity of the toner is insufficient and the transfer efficiency of the toner from the photoreceptor to the transfer paper may be reduced. Is not sufficiently adhered to the surface of the toner particles and is present in a free state, so that the external additive alone adheres to the surface of the photoconductor to be contaminated, or the photoconductor surface is scraped off. Side effects such as dirt and dirt may occur.

As the external additive, inorganic fine particles can be preferably used for the purpose of improving fluidity and chargeability. The primary particle size of the inorganic fine particles is preferably 5 mμ to 2 μm, particularly preferably 5 mμ to 500 mμ. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g.
Specific examples of inorganic fine particles include silica, titanium oxide, alumina, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, and diatomaceous earth. And chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.
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 resin such as silicone, benzoguanamine, and nylon, thermosetting Polymer particles made of a functional resin.

Such external additives can be surface treated to increase hydrophobicity, thereby preventing deterioration of flow characteristics and charging characteristics even under high humidity. Examples of preferable surface treatment agents include 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. Is mentioned.
In the present invention, among the above external additives, silica, titanium oxide, alumina and the like are preferable, and silica subjected to hydrophobic treatment is particularly preferable.

[Modified polyester resin (i)]
The modified polyester resin (i) in the present invention means that a functional group contained in an acid or alcohol monomer unit and a bonding group other than an ester bond are present in the polyester resin, or resin components having different structures are present in the polyester resin. It has a structure bonded by a covalent bond, an ionic bond or the like.
For example, a polyester terminal is reacted so as to generate a bond other than an ester bond, specifically, a functional group such as an acid group or an isocyanate group that reacts with a hydroxyl group is introduced at the terminal, and further reacted with an active hydrogen compound. Those obtained by denaturing or extending the ends are also included. Further, compounds having a plurality of active hydrogen groups include those in which polyester ends are bonded to each other (urea-modified polyester, urethane-modified polyester, etc.).
In addition, a reactive group such as a double bond was introduced into the polyester main chain, and radical polymerization was introduced therefrom to introduce a carbon-carbon bond graft component into the side chain or to bridge the double bonds. Also included (styrene modified, acrylic modified polyester, etc.).
In addition, a resin component having a different structure is copolymerized in the main chain of the polyester or reacted with a carboxyl group or a hydroxyl group at the end, for example, a silicone resin having a terminal modified with a carboxyl group, a hydroxyl group, an epoxy group, or a mercapto group Copolymerized products are also included (such as silicone-modified polyester).
This will be specifically described below.

[Synthesis example of polystyrene-modified polyester resin (i)]
724 parts by weight of bisphenol A ethylene oxide 2-mole adduct, 200 parts by weight of isophthalic acid and 70 parts by weight of fumaric acid and 2 parts by weight of dibutyltin oxide are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe. The mixture was reacted for 8 hours at 230 ° C. under reduced pressure, further reacted for 5 hours under reduced pressure of 10 to 15 mmHg, then cooled to 160 ° C., 32 parts by weight of phthalic anhydride was added thereto, and reacted for 2 hours. Next, the mixture was cooled to 80 ° C., 200 parts by weight of styrene, 1 part by weight of benzoyl peroxide and 0.5 parts by weight of dimethylaniline were added to ethyl acetate, and the reaction was carried out for 2 hours. A polystyrene graft-modified polyester resin (i) having a molecular weight of 92,000 was obtained.

[Urea-modified polyester resin (i)]
Examples of the urea-modified polyester resin (i) include a reaction product of a polyester prepolymer (A) having an isocyanate group and amines (B).
Examples of the polyester prepolymer (A) having an isocyanate group include a polycondensate of a polyol (1) and a polycarboxylic acid (2) and a polyester having an active hydrogen group, which is further reacted with a polyisocyanate (3). Can be mentioned. Examples of the active hydrogen group possessed by the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable.

Examples of the polyol (1) include a diol (1-1) and a trihydric or higher 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 these, 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.

  Examples of the trivalent or higher polyol (1-2) include 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

Examples of 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) and the polycarboxylic acid (2) is an equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH], usually 2/1 to 1/1, preferably 1. 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 an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group, usually 5/1 to 1/1, preferably 4 / 1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, the low-temperature fixability deteriorates. When it is less than 1, the urea content in the modified polyester resin decreases, and the hot offset resistance deteriorates.

The content of the polyisocyanate (3) 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. . 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 resin (i) becomes low, and the hot offset resistance deteriorates.

As amines (B), diamine (B1), triamine or higher polyamine (B2), amino alcohol (B3), amino mercaptan (B4), amino acid (B5), and amino groups of (B1) to (B5) (B6) etc. that are blocked.
Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexylmethane, diamines). Cyclohexane, 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.

As (B6) which blocked the amino group of (B1) to (B5), ketimine compounds obtained from the amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) of (B1) to (B5), Examples include oxazoline compounds.
Among these amines (B), preferred are (B1) and a mixture of (B1) and a small amount of (B2).
Furthermore, if necessary, the molecular weight of the modified polyester resin (i) can be adjusted using an elongation terminator. Examples of the elongation terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).

  The ratio of the amines (B) is an equivalent ratio [NCO] / NHx] of the isocyanate group [NCO] in the prepolymer (A) having an isocyanate group and the amino group [NHx] in the amine (B). Usually, it is 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] exceeds 2 or less than 1/2, the molecular weight of the urea-modified polyester resin (i) becomes low, and the hot offset resistance deteriorates. In the present invention, the modified polyester resin (i) may contain a urethane bond together with a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

  The modified polyester resin (i) of the present invention is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the modified polyester resin (i) is usually 10,000 or more, preferably 20,000 to 10,000,000, more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of the modified polyester resin (i) is not particularly limited when an unmodified polyester resin (LL) described later is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. In the case of the modified polyester resin (i) alone, the number average molecular weight is usually 20000 or less, preferably 1000 to 10000, more preferably 2000 to 8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color device are deteriorated.

[Unmodified polyester resin (LL)]
In the present invention, not only the modified polyester resin (i) is used alone, but also the unmodified polyester resin (LL) can be contained as a toner binder resin component together with the (i). By using (LL) in combination, the low-temperature fixability and the glossiness when used in a full-color device are improved, so that it is preferable to use alone. Examples of (LL) include the same polycondensates of polyol (1) and polycarboxylic acid (2) as in the polyester component (i), and preferred ones are also the same as (i). In addition, it is preferable that (i) and (LL) are at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, a similar composition is preferable for the polyester component (i) and the polyester component (LL). In the case of containing (LL), the weight ratio of (i) to (LL) is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, Particularly preferred is 7/93 to 20/80. If the weight ratio of (i) 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. On the other hand, when the weight ratio of (i) exceeds 80%, it is difficult to ensure low temperature fixing performance, which is not preferable.

The peak molecular weight of the unmodified polyester resin (LL) is usually 1000 to 20000, preferably 1500 to 10000, and more preferably 2000 to 8000. If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 20000, low-temperature fixability will deteriorate. The hydroxyl value of (LL) 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 (LL) is preferably 10 to 30 mg / KOH. By giving an acid value, it tends to be negatively charged, and the fixability tends to be further improved. If the acid value is less than 10, sufficient effects are not exhibited. However, when the acid value exceeds 30, particularly when used in a high-temperature and high-humidity environment, the charge amount of the toner may decrease, and problems such as background smearing on the image may occur.
The glass transition point of the unmodified polyester resin (LL) (Tg) is usually 35 to 55 ° C., preferably from 40 to 55 ° C.. If it is less than 35 ° C., the heat resistant storage stability of the toner is deteriorated, and if it exceeds 55 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of the modified polyester resin (i), the dry toner of the present invention tends to have good heat-resistant storage stability even when the glass transition point is low, as compared with known polyester-based toners.

In the present invention, as the storage elastic modulus of the toner binder resin, 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 binder resin, the temperature (Tη) at 1000 poise at a measurement frequency of 20 Hz is usually 180 ° C. or lower, 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 more. More preferably, it is 10 degreeC or more, Most preferably, it is 20 degreeC or more. There is no upper limit for the difference. 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.

(Coloring agent)
As the colorant of the toner of the present invention, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide , Ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow ( 5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phisera Red Parachloro Tonitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolo Red, Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indance Ren Blue (RS, BC), Indigo, Ultramarine Blue, Bituminous Blue, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green , Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake Ki, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used.
The content of the colorant is usually 1 to 15% by weight, preferably 3 to 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 master batch or the master batch, in addition to the above-mentioned modified or unmodified polyester resins, polymers of styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and substituted products thereof. Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Polymer, 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-malein 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

  The masterbatch can be obtained by mixing and kneading a masterbatch resin and a colorant with a high shear force. At that time, 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 method of mixing and kneading an aqueous paste containing water of a colorant together with a resin and an organic solvent, transferring the colorant to the resin side, and removing moisture and organic solvent components, is also possible with a wet colorant. Since the cake can be used as it is, there is no need to dry it, which is preferable. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

(Release agent)
The toner of the present invention can also contain a wax together with the toner binder resin and the colorant. As a result of studies by the present inventors, it has been clarified that the state of wax in the toner particles greatly affects the releasability of the toner at the time of fixing, and the wax is finely dispersed in the toner particles. It has been clarified that good fixing releasability can be obtained by the presence in the vicinity of the surface more than in the center. In particular, it is preferable that the wax has a long diameter and is dispersed to 1 μm or less. However, when a large amount of the release agent is exposed on the toner particle surface, long-term agitation inside the developing device causes the wax to easily come off from the toner particle surface, thereby adhering to the carrier surface or the surface of the member in the developing device. However, the charge amount of the developer may be lowered, which is not preferable. The dispersion of these release agents is judged from an enlarged photograph obtained using a transmission electron microscope.

  Known waxes can be used, and examples thereof include polyolefin waxes (polyethylene wax, polypropylene wax, etc.); long-chain hydrocarbons (paraffin wax, sazol wax, etc.); carbonyl group-containing waxes, and the like. Of these, carbonyl group-containing waxes are preferred. Carbonyl group-containing waxes 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 used in 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 substance as necessary. In particular, a high charge amount can be imparted by fixing the charge control substance to the toner particle surface. That is, by fixing to the toner particle surface, the amount and state of presence on the toner particle surface are stabilized, and the charge amount can be stabilized. In particular, in the toner having the configuration of the present invention, the charge amount stability is increased.
As the charge control substance, all known substances 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 NEG VP2036 of quaternary ammonium salt, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, quinacridone Azo pigments, sulfonate group, carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

In the present invention, the amount of charge control agent used is determined uniquely by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is uniquely limited. 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.
The release agent and charge control agent can be melt-kneaded together with the masterbatch and the resin, and of course, they may be added when dissolved and dispersed in an organic solvent.
Further, in order to remove the developer after transfer remaining on the photosensitive member or the primary transfer medium, a cleaning property improver may be included. Examples of the cleaning property improver include zinc stearate, calcium stearate, stearic acid, and the like. Examples thereof include fatty acid metal salts such as polymer fine particles produced by soap-free emulsion polymerization such as polymethyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

(Production method)
The production method of the dry toner of the present invention is exemplified. The toner binder resin 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 under reduced pressure if necessary. Thus, a polyester having a hydroxyl group is obtained. Next, this polyester is reacted with polyisocyanate (3) at 40 to 140 ° C. to obtain a prepolymer (A) having an isocyanate group. Further, the prepolymer (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a modified polyester resin (i).
When reacting (3) and reacting (A) and (B), a solvent may be used as necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And those inert to the isocyanate (3), such as tetrahydrofuran (such as tetrahydrofuran).
When the unmodified polyester resin (LL) is used in combination with a urea bond, (LL) is produced in the same manner as the polyester having a hydroxyl group, and this is dissolved and mixed in the solution after completion of the reaction of (i). .

The dry toner can be produced by the following method, but is not limited thereto.
(Melting and kneading method)
Toner components such as a toner binder resin containing a modified polyester resin (i), a charge control agent and a pigment are mechanically mixed. This mixing step may be performed under normal conditions using a normal mixer with rotating wings, and is not particularly limited. When the above mixing process is completed, the mixture is then charged into a kneader and melt-kneaded. As the melt kneader, a uniaxial or biaxial continuous kneader or a batch kneader using a roll mill can be used. It is important that the melt-kneading be performed under appropriate conditions so as not to cause the molecular chains of the toner binder resin to be broken. Specifically, the melt kneading temperature should be performed with reference to the softening point of the toner binder resin. If the temperature is too lower than the softening point, cutting is severe, and if the temperature is too high, dispersion does not proceed.

When the above melt-kneading process is completed, the kneaded product is then pulverized. In this pulverization step, it is preferable to first coarsely pulverize and then finely pulverize. At that time, a method of pulverizing by colliding with a collision plate in a jet stream or pulverizing with a narrow gap between a rotor and a stator that rotate mechanically is preferably used.
After the pulverization step is completed, the pulverized product is classified in an air stream by centrifugal force or the like, thereby producing a toner having a predetermined particle diameter, for example, an average particle diameter of 5 to 20 μm. Further, when preparing the toner, in order to improve the fluidity, storage stability, developability, and transferability of the toner, the hydrophobic silica fine powder and the like mentioned above in addition to the toner manufactured as described above are used. Add and mix inorganic fine particles. For mixing external additives, a general powder mixer is used, but it is preferable to equip a jacket or the like to adjust the internal temperature. In order to change the load history applied to the external additive, the external additive may be added in the middle or gradually. Of course, you may change the rotation speed of a mixer, rolling speed, time, temperature, etc. A strong load may be given first, then a relatively weak load, and vice versa.
Examples of the mixing equipment that can be used include a V-type mixer, a rocking mixer, a Ladige mixer, a Nauter mixer, a Henschel mixer, and the like.

  In order to spheroidize the obtained toner particles, a toner material composed of a toner binder resin and a colorant is melt-kneaded and then finely pulverized and then mechanically spheronized using a hybridizer, mechanofusion, etc., so-called There is a method for obtaining a spherical toner by dissolving a toner material called a spray drying method in a solvent in which a toner binder is soluble and then removing the solvent using a spray drying device, and a method for making a spherical toner by heating in an aqueous medium. Although it is mentioned, it is not limited to this.

(Toner production method in aqueous medium)
As an aqueous medium used in the present invention, water alone may be used, but a solvent miscible with water may be used in combination. Examples of miscible solvents include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.), and the like.

  The toner particles may be formed by reacting a dispersion composed of a prepolymer (A) having an isocyanate group in an aqueous medium with (B), or a modified polyester resin (i) produced in advance may be used. . As a method for stably forming a dispersion comprising a modified polyester resin (i) or a prepolymer (A) in an aqueous medium, a toner raw material comprising a modified polyester resin (i) or a prepolymer (A) in an aqueous medium is used. Examples thereof include a method of adding a composition and dispersing it by shearing force. Prepolymer (A) and other toner raw materials such as colorant, colorant masterbatch, release agent, charge control agent, unmodified polyester resin (LL), etc. are mixed when forming a dispersion in an aqueous medium. However, it is more preferable to mix the toner raw materials in advance and then add and disperse the mixture in the aqueous medium. In the present invention, other toner raw materials such as a colorant, a release agent, and a charge control agent are not necessarily mixed when forming particles in an aqueous medium, and are added after the particles are formed. May be. For example, after forming particles not containing a colorant, the colorant can be added by a known dyeing method.

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

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 rotation speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C. Higher temperatures are preferred in that the dispersion made of the modified polyester resin (i) or the prepolymer (A) has a low viscosity and is easily dispersed.
The amount of the aqueous medium used is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight, based on 100 parts by weight of the toner raw material composition containing the modified polyester resin (i) and the prepolymer (A). If the amount is less than 50 parts by weight, the dispersion state of the toner raw material composition is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 2000 parts by weight, it is not economical. Moreover, a dispersing agent can also be used as needed. The use of a dispersant is preferable in that the particle size distribution becomes sharp and the dispersion is stable.

  Anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphates, etc. as dispersants for emulsifying and dispersing the oily phase in which the toner raw material composition is dispersed in a liquid containing water; alkyl Amine salt type such as amine salt, amino alcohol fatty acid derivative, polyamine fatty acid derivative, imidazoline, alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, etc. Quaternary ammonium salt type cationic surfactants; nonionic surfactants such as fatty acid amide derivatives and polyhydric alcohol derivatives; alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl- Amphoteric surfactants such as N- dimethyl ammonium betaine and the like.

  Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [omega-fluoroalkyl (C6- C11) sodium oxy] -1-alkyl (C3-C4) sulfonate, sodium 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonate, fluoroalkyl (C11- C20) carboxylic acid and its 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- (2 hydroxyethyl ) Perfluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) Examples thereof include ethyl phosphate.

  Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (Daikin Kogyo Co., Ltd.), MegaFuck F-l10, 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 Co., Ltd.), and Fgentent F-100, F150 (manufactured by Neos).

Further, as the cationic surfactant, aliphatic quaternary ammonium salts such as aliphatic primary, secondary or tertiary amic acid having a fluoroalkyl group, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, etc. , Benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (manufactured by Asahi Glass Co., Ltd.), Florard FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (Daikin Industries, Ltd.) Manufactured), MegaFuck F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (manufactured by Tochem Products Co., Ltd.), and Footgent F-300 (manufactured by Neos).
Moreover, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite, etc. 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 Such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloroacrylate -2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N- Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or esters of compounds containing vinyl alcohol and a carboxyl group, 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, ethyleneimine Homopolymers or copolymers such as those having a nitrogen atom or its heterocyclic ring, polyoxyethylene, polyoxypropylene, polyoxyethylene Alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonylphenyl ester, etc. Celluloses such as polyoxyethylene, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose and the like can be used.

In addition, when an acid such as calcium phosphate salt or an alkali-soluble substance is used as the dispersion stabilizer, the calcium phosphate salt or the like is removed from the fine particles by a method such as washing with water after dissolving the calcium phosphate salt with an acid such as hydrochloric acid. Remove. It can also be removed by operations such as enzymatic degradation.
When a dispersant is used, the dispersant can remain on the surface of the toner particles. However, it is preferable from the charged surface of the toner that the dispersant is washed and removed after the elongation and / or crosslinking reaction.

Further, in order to lower the viscosity of the toner raw material composition, a solvent in which the modified polyester resin (i) or the prepolymer (A) is soluble can be used. The use of a solvent is preferable in that the particle size distribution becomes sharp. The solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal. Examples of the solvent include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, Ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride are preferred. The usage-amount of the solvent with respect to 100 weight part of prepolymers (A) is 0-300 weight part normally, Preferably it is 0-100 weight part, More preferably, it is 25-70 weight part. When a solvent is used, it is removed by heating under normal pressure or reduced pressure after elongation and / or crosslinking reaction.
The elongation and / or crosslinking 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, it is also possible to spray the emulsified dispersion in a dry atmosphere, completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, and simultaneously evaporate and remove the aqueous dispersant. 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.

  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 classification 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 obtained unnecessary fine particles or coarse particles can be returned to the kneading step and used for forming 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 is preferably performed simultaneously with the classification operation described above.

  By mixing the obtained toner powder after drying together with different kinds of particles such as release agent fine particles, charge control fine particles, fluidizing agent fine particles, and colorant fine particles, or by giving mechanical impact force to the mixed powder. By immobilizing and fusing on the surface, it is possible to prevent detachment of the 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 into 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.) is modified to reduce the grinding air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron system (Made by Kawasaki Heavy Industries, Ltd.), automatic mortar and the like.

(Developer)
When the toner of the present invention is used for a two-component developer, it may be used by mixing it with a magnetic carrier. Part by weight is preferred. As the magnetic carrier, 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.

  The carrier may be coated with a resin, and 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 chloride, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, polytrifluoroethylene resin, polyhexa Fluoropropylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride Dorukatan monomer terpolymer full Alter polymers etc., and silicone resins.

Moreover, you may make conductive powder etc. contain 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 size of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control the electric resistance.
The toner of the present invention can also be used as a one-component magnetic toner or non-magnetic toner that does not use a carrier.

According to the present invention, it is possible to prevent in-machine contamination due to melting of the toner melt in the fixing unit, excellent development stability, filming resistance, low-temperature fixability, and excellent hot offset resistance. It is excellent in charging stability and can provide a toner having a long life.
In addition, a toner container filled with the toner, a developer containing the toner, an image forming method and an image forming apparatus using the developer can be provided.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, this invention is not limited by these Examples. In addition, the part in each example is a weight part.

Example 1
(Synthesis of toner binder resin)
724 parts of bisphenol A ethylene oxide 2-mole adduct, 276 parts of isophthalic acid and 2 parts of dibutyltin oxide were placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, and reacted at 230 ° C. for 8 hours under normal pressure. Furthermore, after making it react under reduced pressure of 10-15 mmHg for 5 hours, it cooled to 160 degreeC and added 32 parts phthalic anhydride to this, and was made to react for 2 hours.
Next, the mixture was cooled to 80 ° C. and reacted with 188 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain an isocyanate-containing prepolymer (1).
Next, 267 parts of the prepolymer (1) and 14 parts of isophoronediamine were reacted at 50 ° C. for 2 hours to obtain a urea-modified polyester resin (1) having a weight average molecular weight of 64,000.
In the same manner as above, 724 parts of bisphenol A ethylene oxide 2-mole adduct and 276 parts of terephthalic acid were polycondensed at 230 ° C. for 8 hours under normal pressure, and then reacted for 5 hours under reduced pressure of 10 to 15 mmHg. A modified polyester resin (a) was obtained.
200 parts of the above urea-modified polyester resin (1) and 800 parts of the unmodified polyester resin (a) are dissolved and mixed in 2000 parts of a 1: 1 mixed solvent of ethyl acetate / MEK (methyl ethyl ketone) to obtain a toner binder resin (1 ) In ethyl acetate / MEK. Part of the mixture was dried under reduced pressure to isolate the toner binder resin (1). The Tg was 62 ° C. and the acid value was 10.

(Create toner)
In a beaker, 240 parts of the ethyl acetate / MEK solution of the toner binder resin (1), 20 parts of pentaerythritol tetrabehenate (melting point: 81 ° C., melt viscosity: 25 cps), and 10 parts of carbon black were placed. The mixture was stirred at 12000 rpm using a mixer, and uniformly dissolved and dispersed.
On the other hand, after 706 parts of ion-exchanged water, 294 parts of hydroxyapatite suspension (Superite 10 manufactured by Nippon Chemical Industry Co., Ltd.) and 0.2 part of sodium dodecylbenzenesulfonate in a beaker were uniformly dissolved, The temperature was raised to 60 ° C., and the toner material solution was added and stirred for 10 minutes while stirring at 12000 rpm using a TK homomixer.
The mixture is then transferred to a Kolben equipped with a stir bar and a thermometer, heated to 98 ° C. to partially remove the solvent, returned to room temperature, and then stirred at 12000 rpm using the same homomixer. The shape was deformed from a spherical shape, and the solvent was completely removed.
Then, after filtering, washing and drying, air classification was performed to obtain base toner particles.
The base toner particles had a volume average particle diameter (Dv) of 6.35 μm, a number average particle diameter (Dn) of 5.57 μm, and Dv / Dn of 1.14.
Next, 100 parts of the base toner particles and 0.5 part of hydrophobic silica were mixed with a Henschel mixer to obtain the toner (1) of the present invention. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 2
(Synthesis of toner binder resin)
In the same manner as in Example 1, 334 parts of bisphenol A ethylene oxide 2-mole adduct, 334 parts of bisphenol A propylene oxide 2-mole adduct, 274 parts of isophthalic acid, and 20 parts of trimellitic anhydride were polycondensed, and then isophorone diisocyanate. 154 parts were reacted to obtain a prepolymer (2).
Next, 213 parts of prepolymer (2), 9.5 parts of isophoronediamine and 0.5 part of dibutylamine were reacted in the same manner as in Example 1 to obtain a urea-modified polyester resin (2) having a weight average molecular weight of 79000.
200 parts of the urea-modified polyester resin (2) and 800 parts of the unmodified polyester resin (a) are dissolved and mixed in 2000 parts of a mixed solvent of ethyl acetate / MEK (volume ratio 1/1), and acetic acid in the toner binder resin (2). An ethyl solution was obtained. Part of the mixture was dried under reduced pressure to isolate the toner binder resin (2). The peak molecular weight was 5000, the Tg was 62 ° C., and the acid value was 10.

(Create toner)
Base toner particles (2) were obtained in the same manner as in Example 1 except that the toner binder resin (1) was changed to the toner binder resin (2) and the dissolution temperature and the dispersion temperature were changed to 50 ° C.
Further, 1.0 part of a zinc salt of a salicylic acid derivative as a charge control agent was mixed with 100 parts of the base toner particles (2), and the mixture was stirred in a heated atmosphere to fix the charge control agent to the toner particle surfaces. The base toner particles had a volume average particle diameter (Dv) of 5.64 μm, a number average particle diameter (Dn) of 4.98 μm, and Dv / Dn of 1.13.
Next, 100 parts of the base toner particles were mixed with 1.0 part of hydrophobic silica and 0.5 part of hydrophobic titanium oxide using a Henschel mixer to obtain toner (2) of the present invention. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 3
(Creation of toner binder resin)
30 parts of urea-modified polyester resin (1) and 970 parts of unmodified polyester resin (a) are dissolved and mixed in 2000 parts of a mixed solvent of ethyl acetate / MEK (volume ratio 1/1), and ethyl acetate of toner binder resin (3) is mixed. / MEK solution was obtained. Part of the mixture was dried under reduced pressure to isolate the toner binder resin (3). The peak molecular weight was 5000, the Tg was 62 ° C., and the acid value was 10.
(Create toner)
The toner (3) of the present invention was obtained in the same manner as in Example 2 except that the toner binder resin (2) was changed to the toner binder resin (3) and the colorant was changed to 8 parts of carbon black. The volume average particle diameter (Dv) of the base toner particles was 6.72 μm, the number average particle diameter (Dn) was 6.11 μm, and Dv / Dn was 1.10. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 4
(Synthesis of toner binder resin)
500 parts of the urea-modified polyester resin (1) and 500 parts of the unmodified polyester resin (a) are dissolved and mixed in 2000 parts of an ethyl acetate / MEK (volume ratio 1/1) mixed solvent, and the ethyl acetate of the toner binder resin (4) is mixed. / MEK solution was obtained. Part of the mixture was dried under reduced pressure to isolate the toner binder resin (4). The peak molecular weight was 5000, the Tg was 62 ° C., and the acid value was 10.
(Create toner)
The toner (4) of the present invention was obtained in the same manner as in Example 1 except that the toner binder resin (1) was changed to the toner binder resin (4) and 8 parts of carbon black was used as the toner material. The volume average particle diameter (Dv) of the base toner particles was 4.98 μm, the number average particle diameter (Dn) was 4.35 μm, and Dv / Dn was 1.14. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 5
(Synthesis of toner binder resin)
750 parts of urea-modified polyester resin (1) and 250 parts of unmodified polyester resin (a) are dissolved and mixed in 2000 parts of a mixed solvent of ethyl acetate / MEK (volume ratio 1/1), and ethyl acetate of toner binder resin (5) is mixed. / MEK solution was obtained. Part of the mixture was dried under reduced pressure to isolate the toner binder resin (5). The peak molecular weight was 5000, the Tg was 62 ° C., and the acid value was 10.
(Create toner)
A toner (5) of the present invention was obtained in the same manner as in Example 1 except that the toner binder resin (1) was changed to the toner binder resin (5). The volume average particle diameter (Dv) of the base toner particles was 5.93 μm, the number average particle diameter (Dn) was 5.25 μm, and Dv / Dn was 1.14. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 6
(Synthesis of toner binder resin)
850 parts of urea-modified polyester resin (1) and 150 parts of unmodified polyester resin (a) are dissolved and mixed in 2000 parts of a mixed solvent of ethyl acetate / MEK (volume ratio 1/1), and ethyl acetate of toner binder resin (6) is mixed. / MEK solution was obtained. Part of the mixture was dried under reduced pressure to isolate the toner binder resin (6). The peak molecular weight was 5000, the Tg was 62 ° C., and the acid value was 10.
(Create toner)
A toner (6) of the present invention was obtained in the same manner as in Example 1 except that the toner binder resin (1) was changed to the toner binder resin (6). The volume average particle diameter (Dv) of the base toner particles was 3.90 μm, the number average particle diameter (Dn) was 3.38 μm, and Dv / Dn was 1.15. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 7
(Synthesis of toner binder resin)
724 parts of bisphenol A ethylene oxide 2-mole adduct and 276 parts of terephthalic acid were subjected to polycondensation at 230 ° C. for 2 hours under normal pressure, and then reacted for 5 hours under reduced pressure of 10 to 15 mmHg to give an unmodified polyester resin having a peak molecular weight of 800 (b )
200 parts of urea-modified polyester resin (1) and 800 parts of unmodified polyester resin (b) are dissolved and mixed in 2000 parts of a mixed solvent of ethyl acetate / MEK (volume ratio 1/1), and ethyl acetate of toner binder resin (7) is mixed. / MEK solution was obtained. Part of the mixture was dried under reduced pressure to isolate the toner binder resin (7). Tg was 45 ° C.
(Create toner)
A toner (7) of the present invention was obtained in the same manner as in Example 1 except that the toner binder resin (1) was changed to the toner binder resin (7). The volume average particle diameter (Dv) of the base toner particles was 5.22 μm, the number average particle diameter (Dn) was 4.50 μm, and Dv / Dn was 1.16. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 8
210 parts of the toner binder resin (1) solution obtained in Example 1 was diluted with 210 parts of ethyl acetate, and 210 parts of this diluted dispersion was treated in the same manner as in Example 1 to form particles after emulsification. Thereafter, the toner (8) of the present invention was obtained in the same manner as in Example 1. The volume average particle diameter (Dv) of the base toner particles was 4.25 μm, the number average particle diameter (Dn) was 3.73 μm, and Dv / Dn was 1.14. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 9
350 parts of the toner raw material composition after the ball mill dispersion obtained in Example 1 was concentrated to 175 parts by an evaporator, and 210 parts of this concentrated dispersion was processed in the same manner as in Example 1 to form particles after emulsification. Thereafter, the toner (9) of the present invention was obtained in the same manner as in Example 1. The volume average particle diameter (Dv) of the base toner particles was 6.95 μm, the number average particle diameter (Dn) was 5.65 μm, and Dv / Dn was 1.23. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 10
210 parts of the toner raw material composition after the ball mill dispersion obtained in Example 1 was diluted with 965 parts of ethyl acetate, and 210 parts of this diluted dispersion was treated in the same manner as in Example 1 to form particles after emulsification. Thereafter, the toner (10) of the present invention was obtained in the same manner as in Example 1. The volume average particle diameter (Dv) of the base toner particles was 3.95 μm, the number average particle diameter (Dn) was 3.43 μm, and Dv / Dn was 1.15. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Example 11
350 parts of the toner raw material composition after the ball mill dispersion obtained in Example 1 was concentrated to 125 parts by an evaporator, and 210 parts of this concentrated dispersion was processed in the same manner as in Example 1 to form particles after emulsification. Thereafter, the toner (11) of the present invention was obtained in the same manner as in Example 1. The volume average particle diameter (Dv) of the base toner particles was 6.84 μm, the number average particle diameter (Dn) was 5.61 μm, and Dv / Dn was 1.22. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Comparative Example 1
(Synthesis of toner binder resin)
354 parts of bisphenol A ethylene oxide 2 mol adduct and 166 parts of isophthalic acid were polycondensed using 2 parts of dibutyltin oxide as a catalyst to obtain a comparative toner binder resin (1) having a peak molecular weight of 4,000. The Tg of the comparative toner binder resin (1) was 57 ° C.
(Create toner)
In a beaker, 100 parts of the above comparative toner binder resin (1), 200 parts of an ethyl acetate solution, and 10 parts of carbon black were placed, and stirred at 12000 rpm using a TK homomixer at 50 ° C., and uniformly dissolved and dispersed. . Then, the toner was converted into a toner in the same manner as in Example 1 to obtain a comparative toner (1) having a volume average particle diameter of 6 μm. The volume average particle diameter (Dv) of the base toner particles was 7.51 μm, the number average particle diameter (Dn) was 6.05 μm, and Dv / Dn was 1.24. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Comparative Example 2
(Synthesis of toner binder resin)
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, 343 parts of bisphenol A ethylene oxide 2-mole adduct, 166 parts of isophthalic acid, and 2 parts of dibutyltin oxide were placed and reacted at 230 ° C. for 8 hours under normal pressure. Furthermore, after reacting under reduced pressure of 10 to 15 mmHg for 5 hours, cooling to 80 ° C., adding 14 parts of toluene diisocyanate in toluene, reacting at 110 ° C. for 5 hours, then removing the solvent, urethane modified with a weight average molecular weight of 98,000 A polyester resin was obtained.
On the other hand, 363 parts of bisphenol A ethylene oxide 2-mol adduct and 166 parts of isophthalic acid were polycondensed in the same manner as in Example 1 to obtain an unmodified polyester resin having a peak molecular weight of 3800 and an acid value of 7.
350 parts of the urethane-modified polyester resin and 650 parts of the unmodified polyester resin were dissolved in toluene, mixed, and then the solvent was removed to obtain a comparative toner binder resin (2). Tg of this resin (2) was 58 ° C.

(Create toner)
100 parts of comparative toner binder resin (2) and 8 parts of carbon black were converted into toner by the following method. First, premixed using a Henschel mixer, kneaded with a continuous kneader, then finely pulverized with a jet pulverizer, and then classified with an airflow classifier to obtain toner particles.
Subsequently, 100 parts of the toner particles were mixed with 1.0 part of hydrophobic silica and 0.5 part of hydrophobic titanium oxide using a Henschel mixer to obtain a comparative toner (2). The volume average particle diameter (Dv) of the base toner particles was 6.50 μm, the number average particle diameter (Dn) was 5.50 μm, and Dv / Dn was 1.18. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Comparative Example 3
(Synthesis of toner binder resin)
Bisphenol A ethylene oxide 2-mole adduct 354 parts and 166 parts of terephthalic acid were polycondensed using 2 parts of dibutyltin oxide as a catalyst to obtain a comparative toner binder resin (3) having a peak molecular weight of 12,000. The Tg was 62 ° C. and the acid value was 10.
(Example of toner production)
In a beaker, put 100 parts of the above comparative toner binder resin (3), 200 parts of ethyl acetate and 4 parts of copper phthalocyanine blue pigment, stir at 12,000 rpm using a TK homomixer at 50 ° C., and uniformly dissolve and disperse. Thus, a comparative toner material solution was obtained.
Then, the toner was converted into a toner in the same manner as in Example 5 to obtain a comparative toner (3). The volume average particle diameter (Dv) of the base toner particles was 6.12 μm, the number average particle diameter (Dn) was 4.64 μm, and Dv / Dn was 1.32. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Comparative Example 4
(Create toner)
In the step of atypifying the base toner particles prepared in Example 1, after partially removing the solvent, the temperature is returned to room temperature and then stirred at 18000 rpm using a TK homomixer to change the shape of the toner particles from a spherical shape. A comparative toner (4) was prepared under the same conditions as in Example 1 except for the above. Other detailed conditions and evaluation results are shown in Tables 1 and 2.

Comparative Example 5
(Create toner)
A toner was prepared in the same manner as in Example 1 except that 100 parts of the base toner prepared in Example 1 was mixed with 0.2 part of hydrophobic silica using a Henschel mixer to obtain a comparative toner (5). . Other detailed conditions and evaluation results are shown in Tables 1 and 2.

[Characteristic measurement method]
<Toner particle diameter [volume average particle diameter (Dv), number average particle diameter (Dn)]>
The particle diameter (volume average particle diameter, number average particle diameter) of the toner particles was measured by a Coulter Counter Model TA-II manufactured by Coulter Electronics.
Using the above measuring apparatus, an interface (manufactured by Nikka) and a PC9801 personal computer (manufactured by NEC) that output number distribution and volume distribution were connected, and a 1% NaCl aqueous solution was prepared using first-grade sodium chloride as the electrolyte. As a measurement method, 0.1 to 5 ml of a surfactant, preferably alkylbenzene sulfonate, is added to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added. Dispersion treatment was performed for -3 minutes. In another beaker, 100 to 200 ml of an electrolytic aqueous solution was placed, and the sample dispersion was added therein to a predetermined concentration to prepare a suspension. Using this suspension, the particle size distribution of 2 to 40 μm particles was measured based on the number using a 100 μm aperture with the Coulter counter model TA-II, and the volume distribution and number distribution of 2 to 40 μm particles were determined. Further, a weight-based weight average particle diameter (D4: the median value of each channel is a representative value of the channel) was obtained from the volume distribution.

<Method of measuring roundness>
A suspension containing particles (the same one as used in the measurement of the particle size of the toner particles described above) is passed through an imaging unit detection zone on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. The method of optical detection band was used. This value can be measured as an average circularity by a flow type particle image analyzer FPIA-1000 (manufactured by Toa Medical Electronics Co., Ltd.).
As a specific measurement method, 0.1 to 0.5 ml of a surfactant alkylbenzene sulfonate as a dispersant is added to 100 to 150 ml of water from which impure solids have been removed in advance, and a measurement sample is further reduced to 0. About 1 to 0.5 g was added. The suspension in which the sample was dispersed was subjected to dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the shape of the toner particles was measured with the above apparatus at a dispersion concentration of 3000 to 10,000 / μl.

<SF-1>
Using a FE-SEM (S-800) manufactured by Hitachi, 100 toner particle images of 2 μm or larger magnified 1000 times were randomly sampled, and the image information was sent via an interface to an image analyzer (Luxex III) manufactured by Nicole. ) And analyzed.
<Melting and kneading of toner>
The toner was melted and kneaded using a lab plast mill. The melt-kneading conditions were performed at 130 ° C. for 15 minutes, and the rotation speed at that time was 50 rpm. The melt-kneaded product was pulverized with a desktop mixer and pelletized with a molding machine.
<Flow tester>
Using an elevated flow tester (CFT-500) (manufactured by Shimadzu Corporation), 1 cm ³ of the above pellet is formed under the conditions of a die pore diameter of 1 mm, a pressure of 20 kg / cm ² , and a heating rate of 3 ° C./min . The temperature corresponding to 1/2 of the height of the outflow end point from the outflow start point when the sample was melted out was defined as the 1/2 outflow temperature.

[Evaluation methods]
An image of A4 paper with a dedicated chart (6% image area) was output by Ricoh's Imagio Neo450, and the following evaluation was performed.
<Image density>
The density of the image area was measured using X-RiTe938.
<Soil dirt>
The density | concentration of the ground part was measured using X-RiTe938.
<Filming>
The presence or absence of toner filming on the surface of the developing roller was visually observed.
○: No occurrence, ×: Occurrence <Toner dissolution>
The presence or absence of toner dissolution in the fixing unit was visually observed.
○: Not generated, ×: Generated <Cold offset>
The presence or absence of occurrence of a cold offset of the toner on the transfer paper was visually observed.
○: No occurrence, ×: Occurrence <Overall evaluation>
The performance was evaluated considering all the evaluation items (initial and 100,000 sheets output).
○: There is no problem at all, ×: There is a point that performance decreases.

Claims (12)

The modified polyester resin (i) as a toner binder resin A toner for including electrostatic image development, 15 minutes the toner at 130 ° C. using a laboplastomill, obtained by melt-kneading at 50rpm rotational speed The effluent temperature of the elevated flow tester of the toner melt-kneaded product is 105 to 120 ° C., the volume average particle diameter (Dv) is 3 to 7 μm, the volume average particle diameter (Dv) and the number average particle diameter (Dn). The ratio (Dv / Dn) of the toner particles having a particle diameter of 1.01 to 1.25, 2 to 4 μm is less than 10% by number and / or the toner particles having a particle diameter of 8 μm or more is less than 2% by volume, the average An electrostatic charge image, wherein an external additive is added and mixed in a ratio of 0.3 to 5.0 parts by weight with respect to 100 parts by weight of a base toner having a circularity of 0.93 to 0.99. Developing toner.   2. The toner for developing an electrostatic charge image according to claim 1, wherein a shape factor SF-1 of the toner is 105 to 170.   3. The electrostatic image developing toner according to claim 1, wherein the modified polyester resin (i) has a urea group.   The electrostatic image developing toner according to claim 1, wherein the external additive is hydrophobized silica. The toner binder resin contains an unmodified polyester resin (LL) together with the modified polyester resin (i), and the weight ratio [(i) / (LL)] of (i) to (LL) is 5/95 to the toner according to any one of claims 1-4, characterized in that the 80/20. The electrostatic image developing toner according to claim 5, wherein the unmodified polyester resin (LL) has a peak molecular weight of 1,000 to 20,000. The toner according to any one of claims 1 to 6, characterized in that by fixing a charge controlling agent on the particle surfaces of the toner base. For developing an electrostatic charge image according to any one of claims 1 to 7, characterized in that is obtained by the volume shrinkage of 10% to 90% of shrinkage rate in an aqueous medium using a particle dispersant solid toner. A toner container, characterized in that filled with toner according to any one of claims 1-8. Developing agent characterized by containing the toner according to any one of claims 1-8. An image forming method using the developer according to claim 10 . An image forming apparatus loaded with the developer according to claim 10 .