JP4123170B2 - Toner and toner production method - Google Patents

Description

  The present invention relates to a toner used for image formation by a digital method, and more particularly to a toner capable of forming a toner image having good fixability on thick paper and offset printing paper.

  Image formation by electrophotography is now shifting to digital. In digital image formation, excellent fine line reproducibility and high resolution, as represented by, for example, developing a small dot image of 1200 dpi (number of dots per inch, 1 inch is 2.54 cm) level. A small-diameter toner capable of developing image properties is essential.

  In Patent Document 1 and Patent Document 2, as an example of producing such a small-diameter toner, a raw material for toner including a polyester resin is emulsified and dispersed in an aqueous medium, and the resin particles in the emulsified dispersion are dispersed in the toner. A method for producing toner that aggregates to size is disclosed.

  Further, as an embodiment of the above-described digital image formation, there is a print-on-demand image forming method that performs printing “as many copies as necessary when necessary”. Image formation by this method does not require the printing to be performed by conventional printing, and it is possible to issue several hundreds of publications or create direct mails and guide letters while changing the address, It has been attracting attention as a powerful image forming means to replace light printing.

  By the way, it has been found that the image formation by the electrophotographic method has a problem in creating the mail and the guide letter with the address changed as described above. That is, when image formation is performed on thick paper such as wedding invitations, mourning postcards, and funeral letters, sufficient fixing cannot be obtained. In particular, postcards and funeral letters for specifications with a gray frame are less likely to exhibit fixing properties in the gray frame part, and the user's hands are stained with unfixed toner, causing paper contamination.

  In addition, when a toner image is formed on a thick paper surface, a large load is applied to the toner particles that cannot be compared with when outputting on paper such as copy paper. The problem is that the surface of the paper is contaminated by fine toner powder.

  Thick paper such as mourning postcards mentioned above is one of the most difficult transfer media. In addition, in order to spread electrophotography as a print-on-demand image forming means, electrophotography is used as a recording medium. It was necessary to be able to stably form a toner image on a printing paper, not a plain paper developed for the purpose, and if this condition could not be cleared, it was not easily accepted by the printing industry.

  For example, commuter passengers often read a paperback book with one hand while holding a leather strap during rush hour, but even in such a situation, they have a `` slipperiness '' that turns the page with one hand, and toner against friction It is required to have a “fixing strength” that does not rub the paper and characters.

  However, the electrophotographic toner image is inferior to the printed material in terms of slipperiness and fixing strength, and is not allowed by publishers, and has been delayed. Even when the toners disclosed in Patent Document 1 and Patent Document 2 described above are used, they have not been solved.

In addition, toner obtained by agglomerating resin particles tends to have a large amount of water in the toner because aggregation is carried out in an aqueous medium. Such toner generates bubbles due to the evaporation of moisture due to heat during fixing. The problem of toner blisters in which toner is detached from the toner image formed by doing so is significant.
JP 2002-296839 A (see paragraph 0011) JP 2002-351140 A (see paragraph 0011)

  An object of the present invention is to provide a print-on-demand system that prints “only as many copies as necessary” by forming a toner image having a good fixing strength on printing paper, which has conventionally been difficult to form a toner image. It is an object of the present invention to provide a toner that can perform image formation.

  Specifically, when a toner image is formed on a thick paper such as an invitation card or a mourning postcard, particularly when a gray halftone image is formed, the toner can be obtained with good fixability without being detached. It is a first object to provide

  It is a second object of the present invention to provide a toner having a good fixing strength capable of obtaining the same slipperiness and fixing strength as a normal printed material when a toner image is formed on a printing paper for offset printing.

  A third object of the present invention is to provide a toner having a particle strength that can withstand the load applied to the toner when an image is formed on thick paper.

  Furthermore, a fourth object of the present invention is to provide a toner which is a toner obtained through the process of aggregating resin particles in an aqueous medium and which does not have a problem of image defects due to the influence of toner blisters.

  The present invention is achieved by the configuration described in any one of the following items.

  [1] A toner obtained by agglomerating resin particles obtained by polyaddition or polycondensation reaction, and containing toner particles containing carnauba wax and 4 to 60 ppm ketones. .

  [2] The toner according to [1], wherein a volatile component contained in the toner particles is 20 to 300 ppm.

  [3] The toner according to [1] or [2], wherein the resin particles are amorphous polyester resin particles.

  [4] The average value of the circularity of the toner is 0.94 to 0.98, the average value of the equivalent circle diameter is 2.6 to 7.4 μm, and the inclination of the circularity with respect to the equivalent circle diameter is −0.050−. The toner according to any one of [1] to [3], wherein the toner is 0.010.

  [5] The toner according to any one of [1] to [4], wherein the toner is formed by externally adding silica or titanium fine particles having a primary particle diameter of 50 to 200 nm.

  [6] A resin formed by polyaddition or polycondensation reaction of a polymerizable monomer is dissolved in a solvent, and the resin solution is dispersed in an aqueous medium. A method for producing a toner, characterized in that the toner according to any one of [1] to [5] is produced by aggregating resin particles formed by removing droplets or a solvent.

  As a result of repeated studies, the present inventor has formed a process of aggregating resin particles obtained by polyaddition or polycondensation reaction, contains carnauba wax as a release agent, and is volatile consisting of ketones. It has been found that when an image is formed using a toner containing 4 to 60 ppm of the component, the halftone image is surely fixed when the image is formed on a thick paper such as a wedding invitation. The present inventor has also found that a toner image having good slipperiness and sufficient fixing strength can be obtained when an image is formed on a sheet for offset printing using the above-described toner.

  Furthermore, the inventor does not feel the problem of odor due to volatile components from the above-mentioned toner during image formation or the image formed product produced, or destroys the toner particles even when a large load is applied to the toner during image formation. It has also been found that toner fine powder is not generated and image defects due to toner blisters are not generated.

  Thus, the present invention has been found that a toner containing carnauba wax and containing 4 to 60 ppm of a volatile component made of ketones solves the problems of the present invention.

  The reason why the toner according to the present invention has made it possible to exhibit good fixing performance even on invitation cards, postcards for mourning, and paper for offset printing, which are very thick papers for forming toner images. However, it is presumed that the volatile component consisting of carnauba wax and ketones contained in the toner particles contributes to the improvement of the fixing property in some form.

  That is, a volatile component composed of ketones reacts with a hydroxyl group on the surface of the transfer paper composed of cellulose to form a chemical bond, or the carnauba wax and the volatile component are formed between the cellulose fibers constituting the transfer paper. It is presumed as a factor that contributes to the improvement of the fixability that the adhesive strength between the toner image and the transfer paper is improved by functioning as an adhesive between the transfer paper and the toner.

  In particular, when a large amount of images is formed at high speed, the surface temperature of the transfer paper rises to around 125 ° C. due to heat from the heat roll. It is presumed that the reaction with the hydroxyl group on the surface of the transfer paper due to is promoted, or that the volatile component moves out of the toner particles and is adsorbed between the cellulose fibers.

  On the other hand, the presence of the volatile component is concerned about the problem of generating an odor peculiar to the image forming product itself at the time of fixing, but in the present invention, the amount of the volatile component in the toner particles is within the range described in the above configuration. At the same time, it is confirmed that the fixing property is improved and the problem of odor is not generated.

  Also, due to the influence of volatile components, when image formation was performed on both sides, there was a concern about the so-called tacking problem that toner images lightly adhere to each other when they are brought into contact with each other in an uncooled state. In the present invention, no tacking was observed.

  Thus, the present invention is presumed to have improved the adhesive strength between toner particles and paper by the action of volatile components comprising ketones contained in the toner particles. As described above, the improvement in the fixing strength of the toner particles on the transfer paper is effective for image formation using a small-diameter toner in which it is difficult to obtain a sufficient fixing strength because the contact area between the toner particles and the transfer paper is small. Is.

  In the present invention, it was confirmed that the toner particles have a stable particle strength without being destroyed although a large load is applied to the toner particles when a toner image is formed on thick paper. This is because the release agent region made of carnauba wax in the toner particles absorbs the impact applied to the toner, and the volatile component in the toner gives adhesion to the interface between the resin phase and the release agent phase. It is presumed that the strength of the toner particles has been improved.

  In the present invention, it has been confirmed that high strength can be imparted to the toner particles as described above, and strong negative chargeability can be obtained. Therefore, the toner according to the present invention is particularly suitable for image formation with a non-magnetic one-component toner.

  The reason why the toner according to the present invention can obtain a strong negative chargeability is that a resin such as a polyester resin, a polyol resin, or a polyurethane resin has a strong chargeability, and the shape of the rounded toner particles tends to rotate. This is presumed to efficiently promote frictional charging.

  According to the present invention, an image was formed on a thick paper such as an invitation or mourning postcard or a paper for offset printing using a toner containing 4 to 60 ppm of a volatile component composed of carnauba wax and ketones. In some cases, it was confirmed that a toner image having no good fixing strength and no odor and having no problem of toner blisters can be obtained.

  As a result, it becomes possible to form a toner image on thick paper or paper for offset printing, which could not be achieved with the prior art, and instead of the conventional printing that had to make a plate with a small amount of bookbinding, We have made it possible to provide book-binding work that is a print-on-demand system, which is a bookbinding system that outputs only the required number of images when necessary.

  The present invention relates to a toner containing 4 to 60 ppm of a volatile component composed of carnauba wax and ketones in toner particles formed by producing resin particles by polyaddition or polycondensation reaction and aggregating the resin particles. . Hereinafter, the toner according to the present invention will be described in detail.

<Polyaddition reaction and polycondensation reaction>
The resin constituting the toner according to the present invention is obtained by polyaddition or polycondensation reaction.

  Here, the polycondensation reaction refers to a reaction in which a compound having a plurality of functional groups repeats the condensation reaction one after another while releasing a low-molecular compound such as water or alcohol to form a polymer. Usually, examples of well-known polycondensation reactions include, for example, those in which water is released by the reaction of hexamethylenediamine and adipic acid to produce polyamide (66 nylon), or alcohols from ethylene glycol and terephthalic acid esters. The reaction which produces | generates polyester (polyethylene terephthalate) with elimination | elimination of is mentioned.

  On the other hand, the polyaddition reaction is a reaction in which a new bond is formed by performing an addition reaction between functional groups of a compound having a functional group, and this reaction is sequentially repeated to form a polymer. A polymer is formed without the release of a low molecular compound such as a condensation reaction.

  In addition, the polyaddition reaction is different from an addition polymerization reaction such as radical polymerization because the reaction between functional groups is sequentially repeated as described above. Usually, examples of well-known polyaddition reactions include those that form polyurethane from hexamethylene diisocyanate and tetramethylene glycol.

Carnauba wax
The toner according to the present invention contains carnauba wax (hereinafter also referred to as carnauba wax). Carnauba wax is a natural wax refined from palm tree called Pelmeria de carnuba and has excellent properties such as gloss, emulsification, water repellency, waterproofing and the like.

  Carnauba wax is produced by liberating wax from the leaves and stems of the palm tree, and removing impurities by heating and dissolving. As the carnauba wax used as a release agent for toner, the highest natural grade obtained by cutting and drying young leaves of palm trees that have not yet opened, and beating them to separate the wax from the veins. Low-grade carnauba wax obtained by boiling and removing the leaves, fallen leaves, and stems of palm trees and removing impurities, according to the quality improvement method disclosed in Japanese Patent No. 2680997 Those purified by repeating the molecular distillation method are used.

  As the physical properties of the carnauba wax used in the toner according to the present invention, the acid value is 10.0 or less, preferably 0.1 to 8.0, more preferably 0.4 to 6.0. A lower acid value of carnauba wax is preferable from the viewpoint that the cohesiveness of the resin particles is stable and the particle size distribution becomes sharp because it does not generate metal salts and insoluble matter added during toner production. Is.

  The saponification value of carnauba wax is 70 to 95, preferably 75 to 90, more preferably 78 to 88. By having a saponification value within the above range, carnauba wax is preferable because it can exhibit a surfactant-like function in addition to a function as a release agent in the toner particles.

  The measurement methods for measuring the physical properties of carnauba wax such as acid value and saponification value are generally well known as disclosed in the test method based on the standard oil and fat test method and the Japanese Pharmacopoeia 13th revised edition D-18. The measurement method is used.

  Moreover, melting | fusing point is 75-90 degreeC, Preferably it is 80-88 degreeC. The melting point is measured by a generally well-known method such as the above test method or DSC method.

  The kinematic viscosity at 100 ° C. measured by a Brookfield rotational viscometer is 15 to 35 cps, preferably 20 to 30 cps, and more preferably 22 to 28 cps.

  The iodine value is 5 to 14, preferably 8 to 12, and the penetration according to JIS K 2235-1991 is preferably 1.0 or less.

  The carnauba wax used in the toner according to the present invention has a paraffin hydrocarbon composition of 1 to 3% by mass, a resin component composition of 1.5 to 5.5% by mass, and a benzene-soluble component of 4 to 12% by mass. %, And the composition functions as a factor for improving the sliding property of the toner image at a low temperature. These compositions are also measured based on the above-mentioned standard fat test method and Japanese Pharmacopoeia 13th revised edition D-18.

  Examples of the carnauba wax include flakes, granules, powders, and emulsified emulsions, and those having flakes are particularly preferable from the viewpoint of toner production. In addition, since the powder product has a tendency to decrease its solubility due to air oxidation during storage, a flake-shaped product is preferable as a form that exhibits the original performance of carnauba wax.

  Moreover, you may mix and use the other wax mentioned later to a carnauba wax.

  In the present invention, it is possible to control the content of volatile components in toner particles, which will be described later, according to the degree of purification of carnauba wax. As a purification method of carnauba wax, there is a purification by molecular distillation method in which impurities are evaporated and removed by instantaneous heating in high vacuum. In addition, as a concrete refinement | purification technique by the molecular distillation method applicable to the carnauba wax used by this invention, what is disclosed by Unexamined-Japanese-Patent No. 11-209785 is mentioned, for example.

  The content of the carnauba wax contained in the toner according to the present invention is usually 1 to 30% by mass, preferably 2 to 20% by mass, and more preferably 3 to 15% by mass. Specifically, when the toner is measured by DSC, the endothermic amount by carnauba wax is 4 to 24 J / g, preferably 5 to 15 J / g, and more preferably 6 to 12 J / g.

<Volatile components>
The toner according to the present invention is characterized in that the toner particles contain 4 to 60 ppm of a volatile component made of ketones. Here, ketones refer to compounds represented by the following structural formula (1).

In the formula, R ₁ and R ₂ is an alkyl group which may 1 to 25 carbon atoms which may have a substituent, or a full Eniru group.

  In the toner according to the present invention, ketones may be contained in carnauba wax, or may be directly added to toner particles.

  As a method for quantifying the volatile components contained in the toner according to the present invention, a quantification method using a head space type gas chromatograph may be mentioned. This method can be measured using a detection method such as an internal standard method used in ordinary gas chromatographs.

  In the head space type gas chromatograph quantitative method, the toner is sealed in an open / close container, heated at the time of thermal fixing of a copying machine or the like, and the gas in the container is quickly filled with volatile components. Is injected into a gas chromatograph to measure the amount of volatile components, and MS (mass spectrometry) is also performed.

  Hereinafter, a measurement method using a head space type gas chromatograph will be described in detail.

<Headspace gas chromatograph measurement method>
1. Sample collection A 0.8 g sample is collected in a 20 ml headspace vial. The sample amount is weighed to 0.01 g (necessary for calculating the area per unit mass). Seal the vial with a septum using a dedicated crimper.

2. Heating the sample Place the sample in a 170 ° C constant temperature bath and heat for 30 minutes.

3. Setting of gas chromatographic separation conditions A column coated with silicon oil SE-30 so as to have a mass ratio of 15% and packed in a column having an inner diameter of 3 mm and a length of 3 m is used as a separation column. The separation column is attached to a gas chromatograph, and He is used as a carrier to flow at 50 ml / min. The temperature of the separation column is set to 40 ° C., and measurement is performed while the temperature is increased to 260 ° C. at a temperature increase rate of 15 ° C./min. Hold for 5 minutes after reaching 260 ° C.

4). Introduction of sample The vial bottle is taken out from the thermostatic chamber, immediately 1 ml of gas generated from the sample is collected with a gas tight syringe, and this is injected into the separation column.

5. Calculation A calibration curve is prepared in advance using the aromatic hydrocarbon compound used as the internal reference material, and the concentration of each component is determined.

6). Equipment (1) Headspace conditions Headspace device HP 7694 “Head Space” manufactured by Hewlett-Packard Company
Sampler "
Temperature conditions Transfer line: 200 ° C
Loop temperature: 200 ° C
Sample amount: 0.8 g / 20 ml vial (2) GC / MS conditions GC: HP5890 manufactured by Hewlett-Packard Company
MS: HP5971 manufactured by Hewlett-Packard Company
Column: HP-624 30m x 0.25mm
Oven temperature: 40 ° C (3min) -15 ° C / min-260 ° C
Measurement mode: SIM
The content of the volatile component is a value obtained by converting the amount of the organic compound in the gas phase when the toner is heated at 170 ° C. for 30 minutes into toluene.

  As a volatile component composed of ketones in the toner according to the present invention, it is preferable that 1 to 10 ppm of benzophenone is detected. Benzophenone is usually not detected even when carnauba wax alone is analyzed, and is probably produced by reaction of some substance remaining in carnauba wax by the action of heat, for example, in the aggregation process during toner production It is guessed.

  In the toner according to the present invention, the content of volatile components composed of ketones is 4 to 60 ppm, preferably 6 to 45 ppm. The amount of volatile components contained in the toner can be controlled by the degree of purification of the carnauba wax. Specifically, the degree of purification of carnauba wax is improved by repeating the molecular distillation treatment, and the content of volatile components is reduced.

  Further, the toner according to the present invention has a volatile component derived from the production process of resin particles such as ethyl acetate, butanol, and xylene in addition to the volatile component composed of the above-mentioned ketones. The content of the component is 20 to 300 ppm.

  As specific measurement results, it is preferable that 0.5 to 24 ppm of ethyl acetate, 0.5 to 28 ppm of butanol, and 0.1 to 30 ppm of xylene are detected.

<Toner shape>
The toner according to the present invention preferably has an average circularity (shape factor) of 0.94 to 0.98 represented by the following formula when 2000 or more toner particles having a particle diameter of 1 μm or more are measured. Is 0.96-0.97.

Circularity = (perimeter of equivalent circle) / (perimeter of toner particle projection image)
= 2π × (particle projected area / π) ^1/2 / (periphery length of toner particle projected image)
Here, the equivalent circle is a circle having the same area as the toner particle projection image, and the equivalent circle diameter is the diameter of the equivalent circle.

  In addition, as a measuring method of the said circularity, it can measure by FPIA-2000 (made by Sysmec). At this time, the equivalent circle diameter is defined by the following equation.

Equivalent circle diameter = 2 × (projected area of particle / π) ^1/2
The toner according to the present invention has an average equivalent circle diameter of 2.6 to 7.4 μm, and an inclination of circularity with respect to the equivalent circle diameter of −0.050 to −0.010. preferable. More preferably, the average value of the equivalent circle diameter is 3.4 to 6.6 μm, and the inclination of the circularity with respect to the equivalent circle diameter is −0.040 to −0.020.

  The present inventors have developed particles having a large mass and low circularity like a wedge on the dot latent image, and developed particles having a small diameter and high circularity so as to fill the gap. Adjustments were made to fill. Then, for example, even if dust was generated by transfer, dust was generated from particles with a small mass, and it was found that the outline of the dots remained firmly. However, if the circularity and equivalent circle diameter of the particles are distributed discretely, the effect is insufficient, and there is a problem that selective development and selective transfer are likely to occur.

  Therefore, by deriving the concept of continuously changing the circularity gradient with respect to the equivalent circle diameter, the problems of selective development and selective transfer were solved, and a range in which good fixing performance was exhibited was found.

  The inclination of the equivalent circle diameter is measured by measuring the equivalent circle diameter of the toner particles with a flow particle image analyzer FPIA-2000, and the relationship with the corresponding circularity is represented by the horizontal axis: equivalent circle diameter (μm) -vertical. Axis: Draw as a degree of circularity, and see the linear correlation (y = αx + b), α is the slope of the equivalent circle diameter.

At this time, R ² (R squared) is preferably 0.35 to 0.95 from the viewpoint of improving charging uniformity and halftone uniformity. Here, R is represented by the following general formula (1).

General formula (1)
R = A / B
In the formula, A and B each represent the following formula.

A = nΣXY− (ΣXΣY)
B = (nΣX ² − (ΣX) ² ) × ((nΣY ² ) − (ΣY) ² )
X represents an equivalent circle diameter (μm), and Y represents circularity.

  In order to produce a toner having an equivalent circle diameter gradient, small-sized spherical toner particles may be mixed with irregularly-shaped toner particles having a slightly larger particle diameter. Alternatively, in the method of assembling toner particles by associating resin particles described later, after adding an aggregating agent in the associating step, the shape of the stirring blade is appropriately selected, the stirring strength is controlled, and a shearing force is applied to the larger particles. As an easy condition, a method of shifting to a filtration and drying process may be used. Preferably, the toner production apparatus and the flow type particle image analysis apparatus described above are connected in-line, and production is performed while adjusting the conditions as appropriate while monitoring the inclination α.

  Preferably, after adding a stopper that stops aggregation of the resin particles and the colorant, the toner particles are further grown by 0.2 to 1.0 μm, for example, by re-addition of a salting-out agent or addition of a surfactant. It is possible to control to be within the scope of the present invention.

<Binder resin>
Next, the binder resin constituting the toner according to the present invention will be described.

  The binder resin that is a constituent material of the toner used in the present invention is preferably a resin that forms a resin by polyaddition or polycondensation reaction of monomers, and can form a dispersion of resin particles in an aqueous medium. Are preferred.

  Specific resins obtained by polyaddition or polycondensation include polyurethane resins and epoxy resins in addition to amorphous polyester resins, urethane-modified polyester resins, and polyol resins.

  Here, the amorphous amorphous polyester refers to a polyester molecule in which a clear crystal structure is not recognized by X-ray diffraction occupies 50 mol% or more of all constituent molecules. More specifically, an amorphous polyester is a compound in which molecules having a crystallinity of less than 0.1 occupy 50 mol% or more.

  The crystallinity here is measured by density, heat of fusion, X-ray diffraction, NMR (nuclear magnetic resonance spectrum), and the crystal region is expressed in mass ratio (percentage).

《Amorphous polyester resin》
Examples of polyvalent carboxylic acids used in amorphous polyester resins include terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, diphenic acid, and sulfoterephthalic acid. , 5-sulfoisophthalic acid, 4-sulfophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, 5 [4-sulfophenoxy] isophthalic acid, sulfoterephthalic acid, and / or their metal salts, ammonium salts, etc. Aromatic dicarboxylic acids, aromatic oxycarboxylic acids such as p-oxybenzoic acid p- (hydroxyethoxy) benzoic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, 1,6-hexamethylenedicarboxylic acid, etc. Aliphatic dicarboxylic acid, fumaric acid, maleic acid, ita Of unsaturated aliphatic and alicyclic dicarboxylic acids such as acid, hexahydrophthalic acid and tetrahydrophthalic acid, and other polyvalent carboxylic acids such as trimellitic acid, trimesic acid and pyromellitic acid. Examples thereof include polyvalent carboxylic acids.

  Examples of the polyhydric alcohol used in the amorphous polyester resin include aliphatic polyhydric alcohols, alicyclic polyhydric alcohols, aromatic polyhydric alcohols, and the like. Aliphatic polyhydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 2,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, Neopentyl glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol, aliphatic diols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, trimethylolethane, trimethylolpropane, Examples include triols and tetraols such as glycerin and pentaelsitol. Examples of alicyclic polyhydric alcohols include 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, spiroglycol, hydrogenated bisphenol A, ethylene oxide adduct and propylene oxide adduct of hydrogenated bisphenol A, tricyclodecane Examples include diol and tricyclodecane dimethanol.

  As aromatic polyhydric alcohols, para-xylene glycol, meta-xylene glycol, ortho-xylene glycol, 1,4-phenylene glycol, ethylene oxide adduct of 1,4-phenylene glycol, bisphenol A, ethylene oxide adduct of bisphenol A And propylene oxide adducts. Furthermore, examples of polyester polyols include lactone polyester polyols obtained by ring-opening polymerization of lactones such as ε-caprolactone.

  As a preferable example of the polyester resin used in the present invention, for example, the alcohol component is bisphenol A propylene oxide: bisphenol A ethylene oxide = 6: 4 to 8: 2, and the acid component is terephthalic acid: trimellitic acid: 1. , 6-hexamethylenedicarboxylic acid = 8: 1: 1.

  For the purpose of blocking the polar group at the end of the polyester polymer and improving the environmental stability of the toner charging characteristics, a monofunctional monomer may be introduced into the polyester. Monofunctional monomers include benzoic acid, chlorobenzoic acid, bromobenzoic acid, parahydroxybenzoic acid, sulfobenzoic acid monoammonium salt, sulfobenzoic acid monosodium salt, cyclohexylaminocarbonylbenzoic acid, n-dodecylaminocarbonylbenzoic acid Acid, tertiary butylbenzoic acid, naphthalenecarboxylic acid, 4-methylbenzoic acid, 3-methylbenzoic acid, salicylic acid, thiosalicylic acid, phenylacetic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, octanecarboxylic acid, lauric acid, stearyl Acids and monocarboxylic acids such as lower alkyl esters thereof, or monoalcohols such as aliphatic alcohols, aromatic alcohols and alicyclic alcohols can be used.

《Urethane modified polyester resin》
The amorphous polyester resin used in the present invention is modified with a urethane bond in a molecular structure called urethane-modified polyester from the viewpoint of imparting sufficient strength to toner particles and preventing crushing. Also good. Hereinafter, the urethane-modified polyester will be described.

  Examples of the polyester modified with a urethane bond include a reaction product of a polyester prepolymer having an isocyanate group and amines. Examples of the polyester prepolymer having an isocyanate group include those obtained by polycondensation of the above-described polyvalent carboxylic acids and polyhydric alcohols and further reacting a polyester having an active hydrogen group with a polyisocyanate. .

  Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.

  Polyisocyanates 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 combinations of two or more of these.

  The ratio of the polyisocyanate is 5/1 to 1 as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group from the viewpoint of low-temperature fixability and hot offset resistance. / 1, preferably 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1.

  The content of the polyisocyanate component in the prepolymer having an isocyanate group at the terminal is usually 0.5 to 40% by mass, preferably 1 to 30% by mass, and more preferably 2 to 20% by mass. The number of isocyanate groups contained per molecule in the prepolymer having isocyanate groups is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average.

  Examples of the amines include diamines, trivalent or higher polyamines, aminoalcohols, aminomercaptans, amino acids, and those obtained by blocking these amino groups.

  Examples of the diamine include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, isophoronediamine). Etc.); and aliphatic diamines (ethylenediamine, tetramethylenediamine, hexamethylenediamine, etc.) and the like.

  Examples of trivalent or higher polyamines include diethylenetriamine and triethylenetetramine.

  Examples of amino alcohols include ethanolamine and hydroxyethyl aniline. Examples of amino mercaptans include aminoethyl mercaptan and aminopropyl mercaptan. Examples of amino acids include aminopropionic acid and aminocaproic acid.

  In addition, these diamines, trivalent or higher polyamines, amino alcohols and amino mercaptans, and those having amino groups blocked, ketimine compounds obtained from the above amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) And oxazoline compounds. Among these amines, preferred are diamine and a mixture of a diamine and a small amount of a trivalent or higher polyamine.

  Furthermore, the molecular weight of the urethane-modified polyester 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 amines is usually 1/2 to 2/1 as an equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the prepolymer having isocyanate groups and amino groups [NHx] in amines. The ratio is preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2.

  The urethane-modified polyester used in the present invention is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the urethane-modified polyester is usually 10,000 or more, preferably 20,000 to 10,000,000, and more preferably 30,000 to 1,000,000 from the viewpoint of hot offset resistance.

  The number average molecular weight of the urethane-modified polyester is not particularly limited when a polyester not modified with urethane, which will be described later, is used in combination, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. In the case of urethane-modified polyester alone, the number average molecular weight is usually 20000 or less, preferably 1000 to 10000, more preferably 2000 to 8000, from the viewpoint of low-temperature fixability and glossiness of toner images.

  In the present invention, it is also possible to form a binder resin by using together a polyester resin modified with a urethane bond and a polyester not modified with a urethane bond. It has been confirmed that using a polyester resin modified with a urethane bond and a polyester not modified with a urethane bond improves glossiness when performing low-temperature fixability and full-color image formation. It has been confirmed that a better result than that obtained is obtained.

  As a binder resin formed by using a resin modified with a urethane bond and a resin not modified with a urethane bond, the resin component not modified with a urethane bond includes a polyol and a polycarboxylic acid in addition to the polyester component described above. The preferred ones are the same as in the case of the polyester resin. The polyester resin not modified with a urethane bond includes a polyester resin modified with a chemical bond other than a urethane bond in addition to the unmodified polyester resin.

  In the case of a binder resin comprising a polyester resin modified with a urethane bond and a polyester resin not modified with a urethane bond, at least a part of the binder resin is compatible with low-temperature fixability and hot offset resistance. Therefore, the polyester resin component modified with a urethane bond and the polyester resin component not modified with a urethane bond preferably have a similar composition.

  In a binder resin that is a combination of a polyester resin that has been modified with a urethane bond and a polyester resin that has not been modified with a urethane bond, the mass ratio of the two resins is from the standpoint of hot offset resistance, heat-resistant storage, or low-temperature fixability. From 5/95 to 80/20, preferably from 5/95 to 30/70, more preferably from 5/95 to 25/75, and particularly preferably from 7/93 to 20/80.

  Moreover, the molecular weight of the peak top of the polyester resin not modified with a urethane bond (the molecular weight that becomes the maximum peak when the molecular weight distribution is measured) is usually 1000 to 30000, preferably 1500 to 10000, more preferably 2500 to 9500. It is. It has been confirmed that good heat-resistant storage stability and stable low-temperature fixability are exhibited when the peak top molecular weight is in the above range. The ratio Mw / Mn between the weight average molecular weight Mw and the number average molecular weight Mn is preferably 1.5 to 4.5.

  The hydroxyl value of the polyester resin not modified with a urethane bond is preferably 5 or more, more preferably 10 to 120, particularly preferably 20 to 80, from the viewpoint of achieving both heat-resistant storage stability and low-temperature fixability. It is.

  The acid value of the polyester resin not modified with a urethane bond is usually preferably from 1 to 30, and from 5 to 20 from the viewpoint of imparting good chargeability to the toner.

<< Polyol resin, epoxy resin >>
Next, resins obtained by polyaddition or polycondensation reactions other than polyester resins will be described. Various types of polyol resins can be used, but as used in the present invention, an epoxy resin, an alkylene oxide adduct of dihydric phenol or its glycidyl ether, and an active hydrogen that reacts with an epoxy group in the molecule. It is preferable to use a polyol obtained by reacting a compound having one in a molecule with a compound having two or more active hydrogens that react with an epoxy group in the molecule. Furthermore, the epoxy resin is particularly preferably at least two or more bisphenol A type epoxy resins having different number average molecular weights. This polyol resin imparts good gloss and transparency, and is effective in offset resistance.

  The epoxy resin used in the present invention is preferably obtained by binding bisphenol such as bisphenol A or bisphenol F and epichlorohydrin. The epoxy resin is at least two or more bisphenol A type epoxy resins having different number average molecular weights in order to obtain stable fixing characteristics and gloss. The low molecular weight component has a number average molecular weight of 360 to 2000, and has a high molecular weight component. The number average molecular weight is preferably 3000 to 10,000. Furthermore, it is preferable that a low molecular weight component is 20-50 mass% and a high molecular weight component is 5-40 mass%. It has been confirmed that an epoxy resin satisfying such conditions can exhibit stable fixing characteristics and good glossiness.

  Specific examples of the alkylene oxide adducts of dihydric phenols used in the present invention include, for example, reaction products of ethylene oxide, propylene oxide, butylene oxide, and mixtures thereof with bisphenols such as bisphenol A and bisphenol F. Is mentioned. The produced adduct may be glycidylated with epichlorohydrin or β-methylepichlorohydrin and used. In particular, diglycidyl ether of an alkylene oxide adduct of bisphenol A represented by the following general formula (2) is preferable.

  N and m are the number of repeating units, and each is 1 or more, and n + m = 2 to 6.

  Moreover, it is preferable from a viewpoint of curl generation | occurrence | production that the alkylene oxide addition product of dihydric phenol or its glycidyl ether contains 10-40 mass% with respect to polyol resin.

  Moreover, when the value of n + m is in the range of 2 to 6, it is confirmed that good performance is exhibited in glossiness and storage stability.

  Examples of the compound having one active hydrogen in the molecule that reacts with the epoxy group used in the present invention include monohydric phenols, secondary amines, and carboxylic acids. Specific examples of monohydric phenols include phenol, cresol, isopropylphenol, aminophenol, nonylphenol, dodecylphenol, xylenol, p-cumylphenol, and the like.

  Secondary amines include diethylamine, dipropylamine, dibutylamine, N-methyl (ethyl) piperazine, piperidine and the like, and carboxylic acids include propionic acid and caproic acid.

  In order to obtain a polyol resin having an epoxy resin part and an alkylene oxide part in the main chain used in the present invention, various raw material combinations are possible. Examples thereof include a method in which an epoxy resin having a glycidyl group at both ends and an alkylene oxide adduct of a dihydric phenol having both glycidyl groups are reacted with dihalide, diisocyanate, diamine, dithiol, polyhydric phenol, or dicarboxylic acid. Among these, it is most preferable to react divalent phenol from the viewpoint of reaction stability.

  Moreover, it is also preferable to use polyhydric phenols and polyhydric carboxylic acids in combination with dihydric phenols as long as they do not gel. Here, the amount of polyphenols and polycarboxylic acids is 15% or less, preferably 10% or less, based on the total amount.

  Examples of the compound having two or more active hydrogens in the molecule that react with the epoxy group used in the present invention include dihydric phenols, polyhydric phenols, and polycarboxylic acids. Examples of the dihydric phenol include bisphenol compounds such as bisphenol A and bisphenol F. Examples of the polyhydric phenols include orthocresol novolacs, phenol novolacs, tris (4-hydroxyphenyl) methane, and 1- [α-methyl-α- (4-hydroxyphenyl) ethyl] benzene.

  Examples of the polyvalent carboxylic acids include malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, phthalic acid, terephthalic acid, trimellitic acid, and trimetic anhydride.

  In addition, when these polyester resins and polyol resins have a high crosslinking density, it becomes difficult to obtain transparency and glossiness, and preferably non-crosslinked or weakly crosslinked (THF insoluble content is 5% or less). preferable.

《Colorant》
The colorant that can be used in the toner according to the present invention will be described.

  Examples of the black pigment used for the preparation of the black toner include carbon black such as furnace black, channel black, acetylene black, thermal black, and lamp black, and examples of the magnetic powder include magnetite and ferrite.

  These inorganic pigments can be used alone or in combination as desired. Further, the content of the inorganic pigment in the toner is preferably 2 to 20% by mass, and more preferably 3 to 15% by mass.

  When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, the content in the toner is preferably 20 to 120% by mass from the viewpoint of developing predetermined magnetic characteristics.

  Conventionally known organic pigments and dyes used in the toner according to the present invention can be used, and specific organic pigments and dyes are exemplified below.

  Examples of the magenta or red organic pigment used in the magenta toner include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And CI Pigment Red 222.

  Examples of orange or yellow organic pigments used in yellow toner include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 185, C.I. I. Pigment yellow 155, C.I. I. And CI Pigment Yellow 156.

  Examples of the green or cyan organic pigment used in the cyan toner include C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. Pigment blue 60, C.I. I. And CI Pigment Green 7.

  Examples of the dye include C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 122, C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93, 95 and the like. These dyes may be used alone or as a mixture of a plurality of dyes.

  The amount of these organic pigments and dyes used is 1 to 20 parts by mass with respect to 100 parts by mass of the binder resin.

<Releasing agent used with carnauba wax>
As the release agent used in the toner according to the present invention, in addition to the above-mentioned carnauba wax, a known one having a property dispersible in an aqueous medium can be used in combination. Specifically, olefin waxes such as polypropylene and polyethylene, modified products of these olefin waxes, natural waxes such as rice wax, amide waxes such as fatty acid bisamides, fatty acid waxes, aliphatic monoketones, fatty acid metal salt systems Examples thereof include waxes, fatty acid ester waxes, partially saponified fatty acid ester waxes, and higher alcohol waxes.

  As a release agent used together with carnauba wax, a toner containing an ester compound having a specific structure described below or a carnauba wax as a release agent can surely exhibit the effects of the present invention. It was confirmed that.

  Moreover, as a suitable mold release agent used together with the carnauba wax constituting the toner of the present invention, there may be mentioned those composed of a crystalline ester compound represented by the following general formula (3).

Formula (3): R1- (OCO-R2) n
(In the formula, R1 and R2 each represent a hydrocarbon group having 1 to 40 carbon atoms which may have a substituent, and n is an integer of 1 to 4).
In General formula (3) which shows a specific ester compound, R1 and R2 respectively show the hydrocarbon group which may have a substituent.

  The hydrocarbon group R1 has 1 to 40 carbon atoms, preferably 1 to 20, and more preferably 2 to 5.

  The hydrocarbon group R2 has 1 to 40 carbon atoms, preferably 16 to 30 carbon atoms, more preferably 18 to 26 carbon atoms.

  In the general formula (3), n is an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4.

  This ester compound can be suitably synthesized by a dehydration condensation reaction between an alcohol and a carboxylic acid. Specific examples of the ester compound include compounds disclosed in JP-A No. 2002-214821.

<Charge control agent>
The toner according to the present invention may contain a charge control agent as necessary. All known charge control agents can be used, such as 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, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of an azo metal complex compound, E-82 of an oxynaphthoic acid metal complex, E of a salicylic acid metal complex -84, phenolic condensate E-89 (above, Orient Chemical Industries), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary Copy charge PSY VP 2038 of ammonium salt, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEGVP 2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, kina Pyrrolidone, in addition to the azo pigment, a sulfonic acid group, a carboxyl group, and a polymeric compound having a functional group such as a quaternary ammonium salt.

  Among these, azo metal complex compounds are preferable, for example, those disclosed in paragraphs 0009 to 12 of JP-A-2002-351150.

  In the present invention, the amount of charge control agent used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method. From the viewpoint of obtaining electrostatic attraction characteristics with the developing roller, fluidity of the developer, or good image density, 0.1 to 10 parts by weight, preferably 0.2 to 100 parts by weight with respect to 100 parts by weight of the binder resin. The range of 5 parts by mass is good.

  In the present invention, a charge control agent is preferably added in the vicinity of the toner particle surface. That is, by adding the toner particles in the vicinity of the toner particle surface, the toner particles can be effectively charged, and the charge control agent can be added so as not to expose the toner particle surface to ensure the fluidity of the toner. is there.

  As a specific content method, for example, there is a method of controlling the amount of charge control agent added to the resin particles constituting the toner particles. That is, a method in which a large amount of charge control agent is added to the resin particles constituting the vicinity of the surface of the toner particles, and the resin particles are aggregated so as to form the toner particle surface with the resin particles to which no charge control agent is added, And a method in which the resin particles containing the charge control agent are aggregated and then encapsulated with a resin component not containing the charge control agent on the surface of the aggregated particles.

  As a method of addition into the resin particles, it is preferable to knead together with the binder resin and adjust the dispersion diameter, but when emulsified in an aqueous medium, the oil phase may be eluted from the dispersed phase to the aqueous phase side. In the case of detachment, it may be added to the aqueous phase side and incorporated into the toner during the aggregation process or drying process.

<External additive>
In the present invention, an external additive may be added to assist the fluidity, developability and chargeability of the toner particles. As specific external additives, silica fine particles having a primary particle diameter of 50 to 200 nm and titanium It is preferable to use inorganic fine particles such as fine particles in combination with hydrophobic silica having a primary particle size of 10 to 25 nm.

  Specific examples of the inorganic fine particles include the aforementioned silica compounds and titanium compounds. For example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica Examples thereof include sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.

  In addition, for example, polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, dispersion polymerization, polycondensation system such as methacrylic acid ester and acrylic acid ester copolymer, silicone, benzoguanamine, nylon, etc., and polymerization by thermosetting resin. Examples thereof include polymer-based fine particles composed of coalesced particles.

  Such an external additive that imparts fluidity to the toner particles can be subjected to surface treatment to increase hydrophobicity and prevent deterioration of fluidity and charging characteristics even under high humidity. Examples of the surface treatment agent include silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, and modified silicone oils.

<Method for dispersing resin particles>
Next, a method for dispersing resin particles in an aqueous medium, which is performed when the toner according to the present invention is manufactured, will be described.

Although the method of producing the dispersion liquid which disperse | distributes the resin particle performed by this invention in an aqueous medium is not specifically limited, The following method is mentioned.
(1) In the case of polyaddition or condensation resin such as polyester resin and polyol resin, the following methods may be mentioned.
(A) A precursor (monomer, oligomer, etc.) or a solvent solution thereof is dispersed in an aqueous medium in the presence of an appropriate dispersant, and then cured by heating or adding a curing agent to obtain resin particles (A (B) After dissolving an appropriate emulsifier in a precursor (monomer, oligomer, etc.) or a solvent solution thereof (preferably in a liquid form, which may be liquefied by heating). Method of phase inversion emulsification by adding water (2) In the case of vinyl resin, resin particles are produced by a polymerization reaction such as suspension polymerization, emulsion polymerization, seed polymerization or dispersion polymerization using monomers as starting materials (3) A polymerization reaction in advance (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc. may be used). Tree made by The method of dispersing in an aqueous medium in the following manner.
(A) The resin prepared above is pulverized using a mechanical pulverizer or jet type fine pulverizer, then spheronized to obtain resin particles, and then dispersed in water in the presence of an appropriate dispersant. (B) A method in which a resin solution obtained by dissolving the prepared resin in a solvent is sprayed in a mist to obtain resin particles, and then the resin particles are dispersed in water in the presence of a suitable dispersant (c) After adding the poor solvent to the resin solution obtained by dissolving the prepared resin in the solvent, or cooling the resin solution previously dissolved in the solvent to precipitate the resin particles, and then removing the solvent to obtain the resin particles (D) Dispersing the resin particles in water in the presence of a suitable dispersant (d) Dispersing a resin solution prepared by dissolving the resin prepared above in a solvent in an aqueous medium in the presence of a suitable dispersant, and heating it. Alternatively, a method of removing the solvent by reducing the pressure (e A method of dissolving a suitable emulsifier in a resin solution obtained by dissolving the prepared resin in a solvent and then adding water to perform phase inversion emulsification As an emulsifier or dispersant used in the above method, a known surfactant is used. (S), a water-soluble polymer (T), etc. are used. Moreover, a solvent (U), a plasticizer (V), etc. can be used together as an auxiliary agent for emulsification or dispersion. Specific examples include those disclosed in paragraphs 0036 to 62 of JP-A No. 2002-284881.

<< Aggregating method of resin particles >>
Next, a toner manufacturing method according to the present invention will be described. As described above, in the present invention, a toner component such as a binder resin, a colorant, a release agent, or a charge control agent is dissolved in an organic solvent, and this solution is mechanically converted into a particulate oil phase in an aqueous medium. The toner particles are formed through a step of dispersing to produce a fine particle dispersion of the toner component and aggregating the fine particles in the fine particle dispersion.

  As described above, the present invention has a step of aggregating resin particles, but the resin particles used for aggregation in the present invention include those containing an organic solvent, for example, a resin solution. These droplets are also included in this category.

  As a specific method for making each toner component fine particles in an aqueous medium, a method in which the toner component is dissolved in an organic solvent to form an oil phase that becomes a dispersed phase in the aqueous medium can be mentioned.

  Dissolved solution dissolved in organic solvent is stirred with a normal impeller, heat-treated as necessary, dissolved and dispersed with a ball mill, sand mill, homogenizer, etc., emulsified and dispersed in an aqueous medium . At that time, an emulsifier such as a homomixer (manufactured by Special Machine Engineering Co., Ltd.), Ebara Milder (manufactured by Ebara Seisakusho), Claremix (manufactured by M Technique Co., Ltd.) or the like is used.

  The desired droplet size and particle size can be controlled by controlling the concentration of the emulsifier, the concentration of the toner component relative to the organic solvent, the ratio of the oily phase in which the aqueous medium and the toner component are dispersed, the number of revolutions during the emulsification dispersion, and the time. Can be distributed. It is preferable to emulsify and disperse to 1/2 to 1/100 of the target toner particle diameter.

  The mass ratio between each toner component and the organic solvent is preferably selected between 1:10 and 1: 1, and the mass ratio between the aqueous medium and the oily phase in which the solution is dispersed is preferably selected between 10: 1 and 1: 1. However, of course, it may be outside this range.

  As an aqueous medium, water or an organic solvent such as methanol or ethanol that can be partially mixed with water, ethanol such as ethanol, ketone such as acetone or methyl ethyl ketone, or ester such as ethyl acetate is used in combination with water. be able to.

  The organic solvent for dissolving and dispersing each toner component is not particularly limited as long as it is insoluble or hardly soluble in water and partially soluble and dissolves the toner component. For example, 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, etc. alone or in combination Can be used. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable.

  As a dispersant for emulsifying and dispersing the oily phase, which is a toner component, in an aqueous medium to a desired particle size, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates and phosphate esters, alkyls 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, polyhydric alcohol derivatives, such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl -N, 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 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-hydroxyethyl) -Fluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is mentioned.

  Examples of cationic surfactants include aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts, and benzaza. Examples thereof include a ruconium salt, a benzethonium chloride, a pyridinium salt, and an imidazolinium salt.

  Moreover, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite, etc. can be used as an inorganic compound dispersant that is hardly soluble in water.

  Further, the dispersed droplets may be stabilized by a polymer protective colloid. Specifically, (meth) acrylic monomers containing acids and hydroxyl groups, vinyl alcohol or ethers with vinyl alcohol, or vinyl alcohol and carboxyl groups disclosed in JP-A-2002-296839 are disclosed. Ester of compounds, homopolymers or copolymers such as those having nitrogen atoms such as acrylamide, methacrylamide or acid chlorides, or heterocyclic rings thereof, and polymeric protective colloid-forming compounds such as polyoxyethylenes and celluloses Is mentioned.

  Next, in order to remove the organic solvent from the emulsified dispersion, it is possible to employ a method in which the entire system is gradually heated to completely evaporate and remove the organic solvent in the droplets. At that time, it is preferable to carry out under reduced pressure because the heating temperature can be lowered. This is to prevent toner components such as a release agent from dissolving in an organic solvent and to prevent abnormal aggregation, association and coalescence of the emulsified dispersion due to heating.

  The organic solvent removal step may be performed before the aggregation step or after the aggregation step. If the organic solvent is removed before the aggregation step, fusion and coalescence of the fine particles after aggregation can be promoted.

  Another treatment method for those dissolved in an organic solvent is to spray the emulsified dispersion into a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, which are combined with an aqueous dispersion. There is a method of evaporating and removing the agent.

  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, particularly various air streams heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used are generally used. Sufficient quality can be obtained with a short processing time such as spray dryer, belt dryer, rotary kiln.

  As agglomeration methods, when fine particles are dispersed in water in a charged state, a method of agglomerating particles by compressing the electric double layer by pouring electrolyte or the like, adsorbing high molecular weight water-soluble polymer between particles A method of aggregating the particles, a method of charging the surface active agent or dispersant that is oppositely charged to neutralize the surface charge of the fine particles and aggregating the particles, and counteracting the adsorbed surfactant or dispersant For example, a method of changing the solubility of the surfactant or dispersant in the aqueous medium to weaken dispersion stability and agglomerating may be employed.

  At that time, it is agglomerated together with the emulsion of the release agent described above and resin fine particles having polar groups to give the manufactured toner a release property at the time of fixing, to enhance the tribocharging property, and to a glass transition. By disposing the resin particles having high points relatively outside the toner, blocking of the toners during high temperature storage can be prevented.

  Examples of the flocculant used include sodium sulfate, ammonium sulfate, potassium sulfate, magnesium sulfate, sodium phosphate, sodium dihydrogen phosphate, disodium hydrogen phosphate, ammonium chloride, calcium chloride, cobalt chloride, and strontium chloride. General inorganic or organic water-soluble salts represented by cesium chloride, barium chloride, nickel chloride, magnesium chloride, rubidium chloride, sodium chloride, potassium chloride, sodium acetate, ammonium acetate, potassium acetate, sodium benzoate, etc. Can be used.

  The concentration of these electrolytes is 0.01 to 2.0 mol / L, more preferably 0.1 to 1.0 mol / L, even more preferably 0.2 to 0.8 mol / L when a monovalent electrolyte is used. The range of is preferable. Furthermore, when a polyvalent electrolyte is used, the amount added may be smaller.

  In the case of a surfactant, those exemplified above, and in the case of a polymer-based aggregating agent, among those that form the above-mentioned polymer protective colloid, those of ultra high molecular weight are particularly suitable. In addition, as a substance to coagulate by coexisting in an aqueous medium, it is possible to use water-soluble organic compounds such as ethanol, butanol, isopropanol, ethyl cellosolve, butyl cellosolve, dioxane, tetrahydrofuran, acetone, methyl ethyl ketone, etc. it can.

  Furthermore, by heating the dispersion after aggregation, the fine particles can be fused together to adjust the shape of the toner to be produced. The particles are spheroidized by the interfacial tension, and the particle shape can be arbitrarily adjusted from spherical to indeterminate depending on the heating temperature, toner viscosity, presence of organic solvent, and the like.

  The obtained dispersion of aggregated particles is sprayed in a dry atmosphere to completely remove the water-insoluble organic solvent remaining in the aggregated particles to form toner fine particles, and the aqueous dispersant is evaporated together. It is also possible to remove it. As a dry atmosphere in which a dispersion of aggregated particles is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, etc., in particular, various air currents heated to a temperature higher than the boiling point of the highest boiling solvent used are generally used. To do. Sufficient quality can be obtained with a short processing time such as spray dryer, belt dryer, rotary kiln. If the operation of re-dispersing (reslurry) is repeated by separating the liquid into solid and liquid before drying and redispersing (reslurry), the used dispersant and emulsifier can be almost removed.

  In addition, when an acid such as calcium phosphate salt or an alkali-soluble one is used as the dispersion stabilizer, the calcium phosphate salt 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. To do. It can also be removed by operations such as enzymatic degradation.

  Generally, the particle size distribution after the agglomeration operation is narrow and can be used as a toner as it is. However, when the particle size distribution is wide and washing and drying are performed while maintaining the particle size distribution, the desired particle size distribution is classified in an air stream. Thus, the particle size distribution can be adjusted.

  In the classification operation, the fine particle portion can also 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 after drying, but it is preferably performed in a liquid in terms of efficiency. The obtained unnecessary fine particles or coarse particles may be returned to a solution in which the toner component is dissolved in an organic solvent and used to form particles. At that time, fine particles or coarse particles may be in a wet state. The dispersant used in the classification operation at this time can be removed simultaneously with unnecessary fine particles from the obtained dispersion.

  By mixing the resulting dried toner powder with dissimilar 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 in a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) has been modified to reduce pulverization air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron system (Made by Kawasaki Heavy Industries, Ltd.), automatic mortar and the like.

<Image formation>
Next, an image forming apparatus that forms an image using the toner according to the present invention will be described.

  FIG. 1 is a schematic view showing an example of an image forming apparatus of the present invention. Reference numeral 34 denotes a photosensitive drum as a member to be charged, which has a photosensitive layer of an organic photoconductor (OPC) on the outer peripheral surface of an aluminum drum base, and rotates at a predetermined speed in the direction of the arrow.

  In FIG. 1, exposure light is emitted from a semiconductor laser light source 31 based on information read by a document reading device (not shown). The exposure light is distributed by the polygon mirror 32 in a direction perpendicular to the paper surface of FIG. 1, and is irradiated onto the surface of the photoreceptor through an fθ lens 33 that corrects image distortion to form an electrostatic latent image. The photosensitive drum 34 is uniformly charged in advance by a charger 35 and starts rotating clockwise in accordance with the timing of image exposure.

  The exposure is particularly preferably digital image exposure in the present invention, but may be analog image exposure.

  The electrostatic latent image on the surface of the photosensitive drum is developed by the developing unit 36, and the formed developed image is transferred to the transfer material 38 that has been transported in time by the action of the transferring unit 37. Further, the photosensitive drum 34 and the transfer material 38 are separated by a separator (separation pole) 39, and the developed image is transferred and supported on the transfer material 38, and is guided to the fixing device 40 and fixed.

  Untransferred toner or the like remaining on the surface of the photosensitive member is cleaned by a cleaning device 41 of a cleaning blade method, the residual charge is removed by pre-charge exposure (PCL) 42, and again by the charger 35 for the next image formation. Uniformly charged.

  Since the toner according to the present invention has high toner particle strength as described above and can obtain strong negative chargeability, it is particularly suitable for image formation using a non-magnetic one-component toner.

  FIG. 2 is a cross-sectional view showing an example of a developing device 36 used for a non-magnetic one-component developer. 34 is a photosensitive drum, 102 is a developing roller, 103 is a metal elastic blade, and 104 is a non-magnetic one-component toner. , 105 are stirring blades, 106 is a recovery plate, and 107 is silicon resin. The developing roller 102 uses a surface whose surface is covered with a silicon resin 107.

  The present invention can also be used in an electrophotographic image forming apparatus, particularly an apparatus for forming an electrostatic latent image on a photosensitive member with a modulated beam modulated with digital image data from a computer or the like. FIG. 3 is a schematic configuration diagram showing a digital image forming apparatus capable of using the toner according to the present invention.

  In FIG. 3, an image forming apparatus 101 processes an automatic document feeder (commonly called ADF) A, a document image reading unit B for reading a document image conveyed by the automatic document feeder, and a read document image. An image control board C, a writing unit D including a writing unit 112 for writing on a photosensitive drum 34 as an image carrier in accordance with data after image processing, a charging drum 35 and a magnetic brush around the photosensitive drum 34 Image forming unit E including image forming means such as developing unit 36, transfer unit 37, separator 39, and cleaning unit 41, and a storage unit for paper feed trays 122 and 124 for storing recording paper P F.

  The automatic document feeder A has a document placing table 126, and a document transport processing unit 128 including a roller group including a roller R1 and a switching unit for appropriately switching a document moving path (no reference symbol). .

  The document image reading unit B is below the platen glass G, and is provided with two mirror units 130 and 131 that can reciprocate while maintaining the optical path length, a fixed imaging lens (hereinafter simply referred to as a lens) 133, and a line-shaped image sensor. The writing unit D includes a laser light source 31, a polygon mirror (polarizer) 32, and the like.

  When viewed from the moving direction of the recording paper P as a transfer material, R10 shown on the front side of the transfer device 37 is a registration roller, and H is shown on the downstream side of the separator 39 is fixing means.

  In the embodiment, the fixing unit H includes a roller having a built-in heating source and a pressure roller that rotates while being in pressure contact with the roller.

  Z is a cleaning means for the fixing means H, and the main element is a cleaning web that can be wound up.

  One of the documents (not shown) placed on the document table 126 is conveyed by the document conveyance processing unit 128, and exposure by the exposure means L is performed while passing under the roller R1.

  The reflected light from the document is imaged on the CCD 135 through the mirror units 130 and 131 and the lens 133 at a fixed position and read.

  The image information read by the document image reading unit B is processed by the image processing means, encoded, and stored in a memory provided on the image control board C.

  The image data is called in response to image formation, and the laser light source 31 in the writing unit D is driven according to the image data, and exposure is performed on the photosensitive drum 34.

  In recent years, in the field of electrophotography where an electrostatic latent image is formed on a photosensitive member and the latent image is developed to obtain a visible image, image quality can be improved, converted, edited, etc., and high-quality image formation is possible. Research and development of image forming methods adopting various digital methods have been actively conducted.

  As a scanning optical system that optically modulates with a digital image signal from a computer or a copy original employed in the image forming method and apparatus, an optical optical modulator is interposed in the laser optical system, and the optical modulation is performed by the acoustooptic modulator. There is an apparatus that directly modulates the laser intensity using a semiconductor laser, and forms a dot image by spot exposure on a uniformly charged photoconductor from these scanning optical systems.

  The beam irradiated from the scanning optical system described above has a circular or elliptical luminance distribution that approximates a normal distribution with a skirt extending from side to side. For example, in the case of a laser beam, the main scanning direction or One or both in the sub-scanning direction is an extremely narrow circle or ellipse of 20 to 100 μm.

  The present invention can be applied not only to monochrome images but also to full-color image formation. For example, a plurality of image formation units are provided, and each image formation unit forms a visible image (toner image) having a different color to produce a full color image. And an image forming method for forming a toner image.

  The toner according to the present invention is suitably used in an image forming method including a step of fixing an image forming support on which a toner image is formed between a heating roller and a pressure roller constituting a fixing device. The

  FIG. 4 is a cross-sectional view showing a typical example of a fixing device used in the image forming method using the toner according to the present invention. The fixing device 40 in FIG. 4 is in contact with the heating roller 71. And a pressure roller 72. In FIG. 4, T is a toner image formed on a transfer paper (image forming support).

  The heating roller 71 has a coating layer 82 made of a fluororesin or an elastic body formed on the surface of the cored bar 81 and includes a heating member 75 made of a linear heater.

  The cored bar 81 is made of metal and has an inner diameter of 10 to 70 mm. Although it does not specifically limit as a metal which comprises the metal core 81, For example, metals, such as iron, aluminum, copper, or these alloys are mentioned.

  The thickness of the cored bar 81 is 0.1 to 15 mm, and is determined in consideration of the balance between the demand for energy saving (thinning) and the strength (depending on the constituent materials). For example, in order to maintain the same strength as that of a cored bar made of iron of 0.57 mm with a cored bar made of aluminum, the wall thickness needs to be 0.8 mm. In particular, it is preferably applied to a fixing roller made of a thin cored bar disclosed in JP-A-2001-51536.

  Specific examples of the fluororesin constituting the coating layer 82 include PTFE (polytetrafluoroethylene) and PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer). The thickness of the coating layer 82 is 50 to 700 μm, preferably 70 to 600 μm when a fluororesin is used.

  Examples of the elastic body for the covering layer 82 include silicone rubber and silicone sponge rubber having good heat resistance such as LTV, RTV, and HTV. The elastic material constituting the covering layer 82 has an Asker C hardness of less than 80 °, preferably less than 60 °. The thickness of the coating layer 82 made of an elastic body is 0.1 to 30 mm, preferably 0.1 to 20 mm.

  As the heating member 75 suitably used as the linear heater, a halogen heater is exemplified.

  The pressure roller 72 is formed by forming a coating layer 84 made of an elastic body on the surface of the core metal 83. The elastic body constituting the covering layer 84 is not particularly limited, and examples thereof include various soft rubbers such as urethane rubber and silicone rubber, and sponge rubber.

  The elastic body constituting the coating layer 84 has an Asker C hardness of 40 ° to 80 °, preferably 45 ° to 75 °, and more preferably 50 ° to 70 °. Moreover, the thickness of the coating layer 84 is 0.1-30 mm, Preferably it is 0.1-20 mm. Although the material which comprises the metal core 83 is not specifically limited, Metals, such as aluminum, iron, copper, and these alloys are mentioned.

  The contact load (total load) between the heating roller 71 and the pressure roller 72 is usually 40 to 350 N, preferably 50 to 300 N, and more preferably 50 to 250 N. This contact load is defined in consideration of the strength of the heating roller 71 (the thickness of the cored bar 81). For example, in a heating roller made of an iron cored bar having a thickness of 0.3 mm, the contact load is 250 N or less. It is preferable that

Further, from the viewpoint of offset resistance and fixing property, it is preferable to 4~10mm the nip width, also, the nip surface pressure be ^{0.6 × 10 5 Pa~1.5 × 10 5} Pa preferable.

  The specific fixing conditions in the fixing device shown in FIG. 4 are such that, for example, the fixing temperature (surface temperature of the heating roller 71) is 150 to 210 ° C. and the fixing linear speed is 230 to 900 mm / sec. It is done.

  Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited thereto. In the following description, “part” means part by mass, and “%” means mass%.

Preparation of Resin Solution 1 (Polyester Resin) In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 103 parts of bisphenol A ethylene oxide 2-mol adduct, 240 parts of bisphenol A propylene oxide 2-mol adduct, terephthalic acid 133 parts, 16.5 parts of 1,6-hexamethylenedicarboxylic acid, 16.5 parts of trimellitic acid and 2 parts of dibutyltin oxide were added and reacted at 230 ° C. for 8 hours at normal pressure. After reacting under reduced pressure conditions of 99 Pa (10 to 15 mmHg) for 5 hours, the reaction mixture was cooled to 110 ° C. to obtain [Polyester (1)] having a peak top molecular weight of 9500 and Mw / Mn = 1.9.

  [Polyester (1)] 280 parts was dissolved and mixed in a mixed solvent of 1900 parts of ethyl acetate and 100 parts of n-butanol to obtain [Resin Solution 1]. In addition, Tg of the resin component in the resin solution 1 was 44 degreeC.

Preparation of Toner 1 [Resin Solution 1] (Tg 44 ° C. of resin component) 100000 parts Carbon black water-containing cake (solid content 50% in water-containing cake) 12000 parts Charge control agent (Spiron Black TRH manufactured by Hodogaya Chemical Co., Ltd.) 1000 parts Carna Uba wax (Carnauba wax No. 1 (flakes) manufactured by Kato Yoko)
10,000 parts of the above materials were dissolved and dispersed by rolling a ball mill filled with zirconia beads in 0.04 parts of myristyl butyl ketone and 200,000 parts of xylene to prepare an oil phase to be a dispersed phase.

Separately
Ion-exchanged water 700,000 parts Sodium dodecylbenzenesulfonate 1000 parts was stirred and dispersed to prepare an aqueous phase to be a continuous phase. The oil phase was introduced into the aqueous phase while stirring with a homomixer (made by Tokushu Kika Kogyo Co., Ltd.), and oil droplets having a volume average particle diameter of about 1 μm were prepared by adjusting the stirring rotation speed. Thereafter, the solvent (ethyl acetate, butanol, xylene) was removed by distillation under reduced pressure at 50 ° C. for 2 hours to obtain a black gray emulsion.

  The obtained dispersion is transferred to a stirring tank equipped with an impeller, and an aqueous solution obtained by dissolving 10,000 parts of aluminum sulfate in 90000 parts of ion-exchanged water is gradually added dropwise while stirring at low speed to form aggregated particles. Thereafter, the liquid temperature was kept at 70 ° C., and part of the aggregation was melted together and confirmed by a scanning electron microscope.

  Thereafter, the mixture was stirred at 95 ° C. for 8 hours, and when the circularity of the toner reached 0.963, it was cooled to 40 ° C. and the stirring was stopped.

  Thereafter, washing with water and filtration were repeated, and the resulting cake was dried under reduced pressure at 40 ° C. for 8 hours to obtain black colored particles. 100 parts of the resulting colored particles, acicular titanium oxide (major axis 120 nm, n-decyltrimethoxysilane treatment) 0.8 part by mass, spherical monodispersed silica (silica sol obtained by sol-gel method is treated with hexamethyldisilazane 1.8 parts by mass of a primary particle diameter of 137 nm, dried and pulverized, and 0.3 part by mass of silica particles (primary particle diameter of 14 nm) produced by a gas phase method and treated with octylmethoxysilane were added to a Henschel mixer. The toner 1 which is a non-magnetic one-component developer was obtained by removing coarse particles and aggregates by passing through a sieve having an opening of 50 μm.

  Here, it was confirmed that the circularity of the toner did not change even after the external additive was added.

  Further, the volatile components contained in the toner 1 were quantified by the head space type gas chromatograph method described above.

Preparation of Toner 2 Toner 2 was prepared in the same manner except that 0.04 part of myristyl butyl ketone was changed to 0.08 part of myristyl methyl ketone in the manufacturing process of toner 1.

Production of Toner 3 Toner 3 was produced in the same manner as in the production process of toner 1 except that carnauba wax was changed to carnauba wax No. 2 (flakes) manufactured by Kato Yoko Co., Ltd.

Production of Toner 4 Toner 4 was produced in the same manner as in the production process of Toner 1 except that Carnauba wax was changed to Carnauba wax No. 3 (flakes) manufactured by Kato Hiroyuki.

Preparation of Toner 5 Toner 5 was prepared by the same production method as Toner 1 except that [Resin Solution 2] obtained by dissolving a polyol resin obtained by the procedure described below was used instead of [Resin Solution 1]. did.

Preparation of Resin Solution 2 (Polyol Resin) In the above reaction vessel, 378 parts of low molecular bisphenol A type epoxy resin (number average molecular weight: about 360), 86 parts of high molecular weight bisphenol A type epoxy resin (number average molecular weight: about 2700) 191 parts of a diglycidylated product of a bisphenol A type propylene oxide adduct, 274 parts of bisphenol F, 70 parts of p-cumylphenol, and 200 parts of xylene were added.

  The temperature was raised to 70-100 ° C. in a nitrogen atmosphere, 0.183 g of lithium chloride was added, the temperature was further raised to 160 ° C., xylene was distilled off under reduced pressure, and polymerization was performed at a reaction temperature of 180 ° C. for 6-9 hours. [Polyol resin (1)] having a softening point of 109 ° C. and a Tg of 58 ° C. was obtained.

  1,000 parts of the above [polyol resin (1)] were dissolved and mixed in a mixed solvent of 1,900 parts of ethyl acetate and 100 parts of butanol to obtain [Resin Solution 2].

Production of Toner 6 Toner 6 was produced through the same production steps as for toner 2 except that the polyol resin (1) was used.

Preparation of Toner 7 In the manufacturing process of Toner 5, Carnauba wax was changed to Carnauba Wax No. 2 manufactured by Kato Yoko Co., and Toner 7 was prepared. In addition, the place distilled off under reduced pressure at 50 degreeC was distilled off by the normal pressure.

Preparation of Toner 8 Toner 8 was prepared in the same manner as Toner 7 except that Carnauba wax was changed to Carnauba wax No. 3 manufactured by Kato Yoko.

Production of Comparative Toner 1 Comparative toner 1 was produced in the same manner except that 0.4 parts of myristyl butyl ketone was used in the production process of toner 1.

Preparation of Comparative Toner 2 Comparative toner 2 was prepared in the same manner except that 0.8 parts of myristyl methyl ketone was used in the toner 2 manufacturing process.

Preparation of Comparative Toner 3 Comparative toner 3 was prepared in the same manner except that in the toner 3 manufacturing process, 0.4 parts of myristyl butyl ketone was used.

Preparation of Comparative Toner 4 Comparative toner 4 was prepared in the same manner except that 0.4 parts of myristyl butyl ketone was used in the manufacturing process of toner 4.

Preparation of Comparative Toners 5 to 8 In the production process of the above toners 1 and 2, the same amount of polypropylene wax as an olefin wax is added instead of carnauba wax, and no myristyl butyl ketone or myristyl methyl ketone is added. In this manner, comparative toners 5 and 6 were produced, and similarly, comparative toners 7 and 8 were produced using polypropylene wax in the production process of the toners 7 and 8.

  Table 1 shows toners 1 to 8 and comparative toners 1 to 8 which are the obtained nonmagnetic one-component developers.

  The values shown in Table 1 are obtained by measuring the toner obtained after finishing the water washing, the filtration step, and the vacuum drying step. Moreover, it was confirmed by measurement that the calorific value of DSC by carnauba wax falls within the range of 8.8 to 9.2 J / g.

  The evaluation was performed using an apparatus in which the image forming apparatus having the digital exposure shown in FIG. 1 is equipped with a developing device using the nonmagnetic one-component developer shown in FIG. The configuration of the fixing device used for image formation is as shown in FIG.

<Fixability on extra-thick paper>
Continuous printing was performed using 500 postcards (thickness 0.4 mm) manufactured by Heart Co., Ltd. and using the image forming apparatus shown in FIG. 1 as an evaluation machine. A gray frame with a relative density of 0.5 was attached to the frame of the postcard. The ranks of the obtained prints were evaluated as follows.

◎: Even if the character is strongly written with a pen attached on the gray frame, the toner does not peel off at all ○: The toner is peeled off when the character is strongly written with the pen attached on the gray frame, but the toner does not peel off when the ballpoint pen is used. Fixing is insufficient and the toner is peeled off and the hand becomes dirty just by holding the gray frame in the hand.

<Generation of fine dots on extremely thick paper>
A 10% halftone dot image was formed on the entire image of the 490th to 495th postcards of the mourning, and the resulting dot image was observed with a loupe to observe the occurrence of dust around the dots.

◎: Dust is hardly detected. ○: Dust is slightly present but not noticeable unless attention is paid. X: Dust is easily detected.

<Fixability to offset printing paper>
Print on 250 paperback paper (60.2g paper, for offset printing, medium: uncoated paper) manufactured by Daio Paper Co., Ltd., turn 10 times with the thumb of one hand, and visually and magnifying smudges around characters Observation was performed at a magnification of 10), and rank evaluation was performed as follows.

◎: No smudges are generated at all ○ ○: Smudge-like stains are not observed with the naked eye, but there is no problem in practical use only by detecting the stains with a magnifying glass ×: The traces of the thumb are blackened It is dirty.

<Odor during image formation>
Ten people engaged in the light printing industry became monitors and evaluated the odor at the fixing part when 5000 images of 12% A4 size blackened area ratio were printed continuously.

◎: Eight or more of 10 people evaluated that odor is not worrisome ○: 6 or more of 10 people smelled slightly but not uncomfortable ×: 5 or more of 10 people complained of odor .

<Odor when binding>
Ten people in their teens to 50s were randomly selected, and the odor was evaluated by turning over the image output material bound by the monitor. Images with a black area ratio of 12% were cut into B6 size and bound to 250 sheets (500 pages).

◎: Eight or more of 10 people evaluated that odor is not worrisome ○: 6 or more of 10 people smelled slightly, but it was not uncomfortable ×: 5 or more of 10 people complained of unpleasant odor It was.

<Evaluation of toner blister generation>
An image is formed so that the toner adhesion amount on plain paper (64 g / cm ² ) is 1.6 mg / cm ^2, and whether or not there is a hole of about 0.1 μm to 0.5 μm on the image, that is, the presence of a toner blister. It was visually observed and ranked as follows.

◎: not observed the occurrence of toner blisters at all ○: 4 cm but ² per 1-2 toner blisters are present, practically problem-free level ×: the presence of 4 cm ² per three or more distinct toner blister Recognized and impractical level.

  The results are shown in Table 2.

  As apparent from the results in Table 2, with the toner according to the present invention, a toner image having a good fixing strength is formed on thick paper such as an invitation or postcard during mourning, and a large load is applied to the toner. It was also confirmed that the toner was not broken.

  Further, it was confirmed that when a toner image was formed on paper for offset printing, a toner image having a good fixing strength was obtained, and no toner blisters were observed.

  On the other hand, with the toner used as a comparative sample, when image formation is performed on thick paper or offset printing paper, the fixing strength found with the toner according to the present invention cannot be obtained, and there is a problem of toner blistering. It was confirmed that.

1 is a cross-sectional configuration diagram illustrating an example of an image forming apparatus using a toner according to the present invention. It is a cross-sectional block diagram which shows an example of the developing device used for a nonmagnetic one-component type developer. 1 is a schematic view of a digital image forming apparatus using toner according to the present invention. 1 is a schematic cross-sectional view of a fixing device using toner according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 31 Semiconductor laser light source 32 Polygon mirror 33 f (theta) lens 34 Photosensitive drum 35 Charging device 36 Developing device 37 Transfer device 38 Transfer material 39 Separator 40 Fixing device 41 Cleaning device 42 Pre-charging exposure 71 Heating roller 72 Pressure roller 75 Heating member 81 Heating roller core 82 Heating roller coating layer

Claims (6)

Agglomerating resin particles obtained by polyaddition or polycondensation reaction,
1. A toner comprising toner particles containing carnauba wax and a volatile component comprising 4 to 60 ppm of ketones. The toner according to claim 1, wherein a volatile component contained in toner particles is 20 to 300 ppm. The toner according to claim 1, wherein the resin particles are amorphous polyester resin particles. The average value of circularity of the toner is 0.94 to 0.98, the average value of equivalent circle diameter is 2.6 to 7.4 μm,
The toner according to any one of claims 1 to 3, wherein the inclination of the circularity with respect to the equivalent circle diameter is -0.050 to -0.010. The toner according to any one of claims 1 to 4, wherein the toner is obtained by externally adding silica or titanium fine particles having a primary particle diameter of 50 to 200 nm. After dissolving a resin formed by polyaddition or polycondensation reaction of a polymerizable monomer in a solvent,
In the dispersion liquid which disperse | distributes this resin solution in an aqueous medium, the resin particle formed by removing the droplet or solvent of this resin solution is aggregated, and it is any one of Claims 1-5 A toner production method comprising producing the toner described above.

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