JP2005196056A - Toner, developer, image forming apparatus, and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dry type toner which exhibits excellent performance in low-temperature fixability, hot offset characteristic, elution from a fixing and cleaning roller, high fineness images, and resolution. <P>SOLUTION: The toner is obtained by removing an organic solvent included in a dispersion in which microdroplet particles containing at least an organic solvent, a binder resin and a colorant are dispersed in an aqueous medium containing resin particulates from the dispersion. The toner is so constituted that the glass transition temperature (Tg) of the toner is 30 to 46°C and the glass transition temperature (Tg) of the resin particulates coating the toner surface is 50 to 70°C, that the 1/2 outflow temperature when the toner is masticated by a laboratory blast mill is 95 to 120°C, and that the 1/2 outflow temperature before the masticating attains 120 to 145°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

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

  In the electrophotographic method, the pressure heating method using a heating roller is a method in which a toner image is transferred by passing the fixing sheet through the surface of the fixing roller and the surface of the fixing roller in contact with the toner image surface under pressure. Fixing is performed. In this method, the surface of the heat roller and the toner image on the fixing sheet come into contact with each other under pressure, so that the thermal efficiency when fusing the toner image on the fixing sheet is extremely good, and the fixing is performed quickly. Can do.

  Since the surface of the heating roller and the toner image are in contact with each other under a molten state and pressure, a part of the toner image adheres to and is transferred to the surface of the fixing roller, which is re-transferred to the next fixing sheet and stains the fixing sheet. The so-called offset phenomenon is greatly affected by the fixing speed and fixing temperature. In general, when the fixing speed is low, the surface temperature of the heating roller is set to be relatively low, and when the fixing speed is high, the surface temperature of the heating roller is set to be relatively high. This is to make the amount of heat applied from the heating roller to the toner to fix the toner substantially constant regardless of the fixing speed.

  Since the toner on the fixing sheet forms several toner layers, especially in a system in which the fixing speed is high and the surface temperature of the heating roller is high, the toner layer that is in contact with the heating roller and the toner layer that is in contact with the heating roller Since the temperature difference with the lowermost toner layer in contact with the fixing sheet is large, when the surface temperature of the heating roller is high, the toner on the uppermost layer tends to cause an offset phenomenon, and the surface temperature of the heating roller. When the toner is low, the toner in the lowermost layer is not sufficiently melted, so that the toner is not fixed on the fixing sheet and a phenomenon of low temperature offset is likely to occur.

  As a method for solving this problem, when the fixing speed is high, a method of increasing the pressure at the time of fixing and anchoring the toner to the fixing sheet is usually performed. With this method, the temperature of the heating roller can be lowered to some extent, and the high temperature offset phenomenon of the uppermost toner layer can be prevented. However, since the shearing force applied to the toner becomes very large, the fixing sheet is wound around the fixing roller, wrapping offset occurs, or the separation nail for separating the fixing sheet from the fixing roller is fixed. It tends to appear in images. Furthermore, since the pressure is high, the line image is crushed at the time of fixing, or the toner is scattered, so that the image quality of the fixed image is likely to deteriorate.

In high-speed fixing, a toner having a lower melt viscosity is generally used than in low-speed fixing, and the surface temperature of the heating roller is lowered to lower the fixing pressure, thereby preventing high temperature offset and wrapping offset. The image is fixed. However, when such a low melt viscosity toner is used for low-speed fixing, an offset phenomenon tends to occur at a high temperature.
Thus, in fixing, a toner having a wide fixing temperature range that can be applied from low speed to high speed and excellent in offset resistance is desired.

  On the other hand, in order to obtain high image quality, the toner particle size is being reduced. When the toner particle size is reduced, the resolution and sharpness of the image are increased, but on the other hand, the fixability of the halftone portion formed with the toner having a small particle size is lowered. This phenomenon is particularly remarkable in high-speed fixing. This is because the amount of toner applied to the halftone portion is small, the toner transferred to the concave portion of the fixing sheet has a small amount of heat applied from the heating roller, and the fixing pressure is also applied to the concave portion by the convex portion of the fixing sheet. It is because it becomes worse because the pressure is suppressed. Since the toner transferred to the convex portion of the fixing sheet in the halftone portion has a thin toner layer thickness, the shearing force applied to each toner particle is larger than that of the solid black portion where the toner layer thickness is thick. Phenomenon is likely to occur, and a low-quality fixed image tends to be obtained.

In order to achieve both fixing performance and hot offset resistance performance, various researches have been conducted up to now, focusing on binder resins. Patent Document 1 discloses at least one maximum in each of a molecular weight region of 10 ^{3 to} 7 × 10 ^{4 and} a region of 10 ⁵ to 2 × 10 ⁶ in a chromatograph measured by gel permeation chromatography of a toner resin. We are proposing the molecular weight distribution of resin that has a value. In Patent Documents 2 and 3, a mold release agent such as polyethylene is introduced while prescribing the molecular weight distribution of the vinyl-based copolymer to achieve both fixability and hot offset. In Patent Document 4, an attempt was made to improve compatibility between low-temperature fixing and hot offset by combining a low-viscosity resin and a high-viscosity resin.

  In addition, a number of applications have been filed for expanding the molecular weight distribution of the binder resin and optimizing the balance between conflicting storability, fixability and hot offset (for example, Patent Documents 2, 3, 5 to 8). In electrophotography, it is necessary to satisfy not only these two conflicting characteristics, but also the heat-resistant storage stability that is greatly influenced by low molecular weight components. Further, Patent Document 9 attempts to improve using a novolak type phenolic resin or using polyurethane in addition to the molecular weight distribution.

These are the effects of molecular weight distribution and the effects of low molecular weight olefins, which improve low-temperature fixing and heat-resistant storage stability, but are not yet sufficient for recent energy savings and low power consumption, and further research is desired.
In particular, in order to improve the low-temperature fixability, it is required to lower the glass transition point (Tg) and molecular weight of the binder resin, but it is difficult to develop a toner that satisfies all of these in consideration of the balance between hot offset and storage stability. There is something.

  Patent Document 10 discloses a practical sphericity of 0.90 to 1.00 comprising an elongation reaction of a urethane-modified polyester (A) as a toner binder for the purpose of improving fluidity, low-temperature fixability and hot offset. A dry toner is disclosed. In addition, it is excellent in powder flowability and transferability when it is a small particle size toner, and is also used in dry toners, especially full-color copiers, etc., which are excellent in both heat storage stability, low-temperature fixability, and hot offset resistance. In this case, a dry toner is disclosed that has excellent image gloss and does not require oil application to a heat roll.

  Further, as an economical method for obtaining such a dry toner, in Patent Documents 11 and 12, a dry toner comprising a toner binder obtained by subjecting an isocyanate group-containing prepolymer to an extension reaction and / or a crosslinking reaction, and a colorant, Disclosed is a dry toner characterized in that the toner comprises particles formed by an extension reaction and / or a crosslinking reaction of the modified polyester (A) with an amine (B) in an aqueous medium. .

  However, the technique described in Patent Document 10 embeds new features and effects in terms of adopting a urethane reaction as a binder, but it is a pulverization method and has a sufficiently low-temperature fixing toner in terms of fixability. In addition, specific conditions are not included for small particle size and spherical shape control. Further, in Patent Documents 11 and 12, although the toner manufacturing method in underwater granulation, when the particles are formed in water, the pigment in the oil phase aggregates at the interface of the aqueous phase, resulting in a decrease in volume resistance and non-uniformity of the pigment. Cause problems with basic toner performance. In addition, in order to achieve oillessness, to achieve small particle size and shape control at the same time, and to use on a machine, the effect cannot be exhibited unless there is a target shape and target characteristics. Each gazette does not sufficiently describe the effect of combination and the effect of fine condition balance on characteristics and construction methods, and the effect may not be sufficiently exhibited for the problem. In particular, toner particles that have been granulated by underwater granulation tend to attract pigment and wax to the surface of the toner, and when the particle size is about 6 μm or less, the specific surface area of the toner particles is large. This is important for obtaining desired charging characteristics and fixing characteristics.

  On the other hand, in a conventional electrophotographic image forming apparatus, a pressure member such as a pressure roller is pressed against a heating member such as a heating roller having a heat source therein, and the recording is performed through a recording medium after image transfer between them. The apparatus mainly includes a thermal fixing device that fixes a toner image on the recording medium while conveying the medium.

  In this type of heat fixing apparatus, a phenomenon called so-called offset may occur in which the toner on the recording medium adheres to the heating member. It is known that when such an offset occurs, the offset toner adheres to the pressure member, and the recording medium is soiled by reverse transfer from the heating member and the pressure member to the recording medium. In order to prevent such an offset, in the conventional heat fixing apparatus, for example, a surface of the heating member is coated with fluorine. However, it is difficult to completely prevent the offset depending on the environmental conditions and the type of the recording medium, and there is still a problem that reverse transfer occurs.

  Therefore, some conventional thermal fixing devices are provided with a cleaning member such as a cleaning roller in contact with the heating member or the pressure member to remove the toner adhering to the heating member or the pressure member. That is, there is a technique that removes toner from the difference in surface releasability by pressing a cleaning member made of a solid metal material against a heating member or pressure member having improved surface releasability.

  Incidentally, in recent years, in an image forming apparatus, in order to prevent wasteful consumption of energy, energization to a heat source is stopped during standby, and the heating member is raised to a fixing temperature by energizing the heat source only at the start of image formation. It is getting warmer. For this reason, it is necessary for the heating member to improve temperature responsiveness. For example, in the case of a heating roller, the thickness is 1 mm or less, and the temperature raising time to the fixing temperature is shortened to about 10 seconds.

  In such an image forming apparatus, since the heat capacity of the heating member is small, the heat transfer to the recording medium at the time of fixing, the heat transfer to the member in contact with the heating member, the flow of air around the heating member, etc. There is a problem that the temperature distribution of the heating member tends to be uneven in the width direction. In addition, it is impossible to make the temperature distribution uniform over the entire region of the heating member in terms of space and cost.

  If the temperature distribution of the heating member becomes non-uniform in the width direction, the fixing performance becomes unstable, and offsets are likely to occur, and the life of the heating member tends to be shortened due to thermal degradation. In particular, when using a polymerized toner manufactured by a polymerization method as described in Patent Documents 10 and 12, there is a problem in that a toner lump attached and deposited on the cleaning member is remelted and reversely transferred to a recording medium. was there. This is because when a pulverized toner manufactured by a pulverization method is used, a toner having a high storage elastic modulus and hardly dissolves adheres to the cleaning member, but when a polymerized toner manufactured by a polymerization method is used, the storage elastic modulus is low. This is because ordinary toner adheres to the cleaning member.

  This problem is particularly noticeable when a small-sized recording medium is passed compared to the maximum size that can be passed. This is because, in the case of a small size, since the sheet passing area is small and the area in contact with the heating member is small, the temperature falls only in the narrow area, and the temperature detection means corresponding to that part instructs the lighting of the heat source. This is because the temperature rises unnecessarily to the temperature of the paper passing area, and the toner on the cleaning member corresponding to the non-paper passing area melts and reversely transfers.

  Therefore, in order to solve such a problem of reverse transfer, in a conventional heat fixing apparatus, as described in Patent Document 13, for example, the temperature distribution of the heating roller is uniform in the width direction. In order to prevent the temperature of the non-sheet passing area of the heating roller from rising excessively.

For example, as described in Japanese Patent Application Laid-Open No. H10-228707, there is a type in which a ventilation hole is provided along the cleaning roller to circulate the air in the heat fixing device along with the rotation of the cleaning roller, thereby preventing the temperature of the cleaning roller from rising.
Japanese Patent Laid-Open No. 5-107803 Japanese Patent Laid-Open No. 5-289399 JP-A-5-313413 JP-A-5-297630 Japanese Patent Laid-Open No. 5-053722 JP-A-6-027733 JP-A-6-074426 JP-A-6-118702 JP-A-8-146661 Japanese Patent Laid-Open No. 11-133665 JP-A-11-149180 JP 2000-292981 A JP-A-9-325550 JP 2002-123119 A

  An object of the present invention is to provide a dry toner for developing an electrostatic charge image that can be fixed satisfactorily immediately after the power is turned on, and can be fixed well at a low power capacity. Another object of the present invention is to provide a dry toner for developing an electrostatic charge image that has a wide releasability from low speed to high speed image forming apparatus and is excellent in offset resistance, blocking resistance, and fluidity. Is. Furthermore, an object of the present invention is to provide a dry toner for developing an electrostatic image in which the toner adhering to the cleaning member is not reversely transferred without lowering the fixing efficiency in the above-described thermal fixing device. It is in.

  Another object of the present invention is to provide a dry toner for developing an electrostatic image capable of obtaining a high-density and high-definition image without fogging from low speed to a high-speed image forming apparatus, and a two-component comprising the toner and a carrier. It is an object of the present invention to provide a developer, a process cartridge containing the toner or the two-component developer, and an image forming apparatus.

As a result of intensive studies to solve the above problems, the present invention has the following configuration.
(1) By removing the organic solvent contained in the dispersion liquid in which the fine droplet particles containing at least the organic solvent, the binder resin, the colorant, and the wax are dispersed in the aqueous medium containing the resin fine particles. The obtained toner has a glass transition point (Tg) of the toner of 30 to 46 ° C., and a glass transition point (Tg) of the resin fine particles coated on the toner surface is 50 to 70 ° C. A dry toner having a 1/2 outflow temperature of 95 to 120 ° C. when the toner is masticated with a lab plast mill, and a 1/2 outflow temperature of 120 to 145 ° C. before mastication.

(2) The dry toner as described in (1) above, wherein an insoluble content of tetrahydrofuran (THF) contained in the toner is 5 to 25% by weight.
(3) The weight average particle size of the toner measured by the Coulter method is 3.0 to 6.0 μm, and the particle size distribution is 1.00 ≦ Dv / Dn ≦ 1.20 (Dv: weight average particle size, Dn : Number average particle diameter). The dry toner according to (1) or (2) above.
(4) In any one of the above (1) to (3), in the particle size distribution measured by the flow type particle image measuring device, the fine powder content of 2 μm or less on the number basis is 15% or less. The dry toner described in 1.

(5) In the particle size distribution measured by the Coulter method, the content of the coarse powder having a particle size of 8 μm or more is 2% by weight or less, according to any one of (1) to (4) above Dry toner.
(6) The dry toner as described in any one of (1) to (5) above, wherein in the particle size distribution measured by the Coulter method, the content of fine powder having a particle size of 3 μm or less is 2% by weight or less. .
(7) The dry toner as described in any one of (1) to (6) above, which has a spindle shape with an average circularity of 0.900 to 0.960 as measured by a flow type particle image measuring device. .
(8) The dry toner as described in any one of (1) to (7) above, wherein the resin fine particles have an average particle size of 10 to 200 nm.

(9) By removing the organic solvent contained in the dispersion liquid in which the fine droplet particles containing at least the organic solvent, the binder resin, the colorant, and the wax are dispersed in the aqueous medium containing the resin fine particles. The obtained toner dissolves or disperses at least a modified polyester resin, a colorant, and a wax capable of reacting with a compound having an active hydrogen group in an organic solvent, and the dissolved or dispersed substance is dispersed in a resin medium in an aqueous medium. A toner obtained by dispersing in the presence of a compound and subjecting it to a polyaddition reaction with a compound having active hydrogen and removing the solvent of the resulting dispersion, wherein the toner contains a modified polyester resin. The dry toner according to any one of (1) to (8).

(10) The modified polyester resin contained in the toner contains a tetrahydrofuran-soluble component, and the tetrahydrofuran-soluble component has a main peak in the region of a molecular weight of 2500 to 10,000 and a number average molecular weight of 1500 to 15000. The dry toner according to (9) above, which has a molecular weight distribution in a range.
(11) The modified polyester resin capable of reacting with the compound having an active hydrogen group contains an isocyanate group, and the polyaddition reaction is an extension reaction and / or a crosslinking reaction. The dry toner according to 10).

(12) A two-component developer using the dry toner according to any one of (1) to (11) and a carrier.
(13) In an image forming apparatus provided with a heat fixing device that fixes a toner image on a recording medium while passing the recording medium between the heating member and the pressure member, the image forming apparatus adheres to the heating member and / or the pressure member. An image forming apparatus including a cleaning member for removing toner, and performing fixing by a fixing device having a surface pressure (roller load / contact area) applied between a heating member and a pressure member of 1.5 × 10 ⁵ Pa or less, An image forming apparatus using the toner or developer according to any one of (1) to (12).

(14) In a process cartridge that integrally supports at least one member selected from a photosensitive member, a charging unit, a developing unit, and a cleaning unit and is detachable from the image forming apparatus main body, the developing unit includes toner or A process cartridge for holding a developer, wherein the toner or developer is the dry toner or developer according to any one of (1) to (12).

  The dry toner of the present invention includes at least an organic solvent contained in a dispersion liquid in which fine droplet particles containing an organic solvent, a binder resin, a colorant, and a wax are dispersed in an aqueous medium containing resin fine particles. A toner obtained by removing, preferably, dissolving or dispersing at least a modified polyester resin, a colorant, and a wax capable of reacting with a compound having an active hydrogen group in an organic solvent. A toner obtained by dispersing a product in an aqueous medium in the presence of resin fine particles, causing a polyaddition reaction with a compound having an active hydrogen group, and removing the solvent of the resulting dispersion. The glass transition point (Tg) of the toner is 30 to 46 ° C., and the glass transition point (Tg) of the resin fine particles coated on the toner surface is 50 ° C. to 70 ° C. A dry toner characterized in that a 1/2 outflow temperature when masticated with a stmill is 95 ° C. to 120 ° C., and a 1/2 outflow temperature before mastication is 120 ° C. to 145 ° C. Excellent performance in fixing property, hot offset property, melting from fixing cleaning roller, high-definition image and resolution.

The present invention is described in detail below.
The present inventors have excellent toner fluidity, transferability, fixability, hot offset property, high image quality, heat-resistant storage stability, and the toner attached to the fixing cleaning roller is reversely transferred without lowering the fixing efficiency in the thermal fixing device. Intensive study was conducted on a toner that does not occur. The dry toners described in Patent Document 11 (Japanese Patent Laid-Open No. 11-149180) and Patent Document 12 (Japanese Patent Laid-Open No. 2000-292981) are based on amines (B) in an aqueous medium of the modified polyester (A). A toner comprising particles formed by an elongation reaction and / or a crosslinking reaction, wherein the toner is granulated in water, and the particle surface of the toner is appropriately covered with a modified polyester. Inside, there is a low Tg polyester and a modified polyester, a wax as a releasing agent is dispersed in the vicinity of the particle surface, and the toner particle surface layer has a particle structure in which polymer resin fine particles are coated on the surface. In the fixing by the heating roller method, it was realized that the low softening polymer with low thermal properties inside the particles oozes out immediately and is used for fixing. In addition, by controlling the thermal characteristics and molecular weight on the surface layer, it is possible to achieve both storability (especially heat resistance) by forming a thin layer of resin fine particles that prevent the softening point binder from blocking due to heat. I made it.

  In addition, by improving the fixability by reducing the particle size of toner particles, low-temperature fixability and storage stability, low-temperature fixability and releasability, and improving image quality by reducing particle size and increasing pigment dispersion I found it to be an excellent toner.

  In normal image output, toner adhered from the recording paper to the fixing roller by electrostatic offset or the like is transferred to the pressure roller at a nip portion where the fixing roller and the pressure roller contact. The toner adhered to the pressure roller is collected by the cleaning roller at the nip portion between the pressure roller and the cleaning roller. The toner adhering to the fixing roller in such a flow is collected by the cleaning roller, and about 1 g of toner is collected by the cleaning roller after 150,000 copies.

  With a pulverized toner composed of a conventional uniform pigment, wax, and resin dispersion, the fixing unit is controlled by a heater without passing the recording paper with the toner attached to the cleaning roller as shown in FIG. There was no problem even if it was rotated. This is because the glass transition point (Tg) of the resin used as the binder is relatively high and a resin around 60 ° C. is used, so that the viscosity of the toner adhering to the cleaning roller when cleaning is increased. Even if the number of copies increases, it is difficult to melt. This is also because the adhering toner is uniform and the temperature at which the toner melts before and after the fixing step does not change.

  However, when a polymer toner having a core / shell structure as described in Patent Document 12 (Japanese Patent Laid-Open No. 2000-292981) is used, heat for melting the polymer resin in the outer shell is required at the time of fixing. However, once the toner undergoes the fixing process, the core / shell structure collapses, the temperature characteristics of the low molecular weight resin that melts at a relatively low temperature dominate, and the toner tends to melt at a temperature lower than the fixing set temperature. For this reason, when the fixing unit is rotated by controlling the heater without passing the recording paper while the toner is attached to the cleaning roller as shown in FIG. 1, the collected toner is melted and pressed from the cleaning roller. Reattaches to the roller and fixing roller. When an image is output in this state, there has been a problem that the melted toner adheres to the recording paper and stains the front and back of the recording paper. This core / shell structure can use low-Tg resin compared to pulverized toner to achieve low-temperature fixability, and it can be used for both storage and low-temperature fixability even if low molecular weight resin is used. However, with respect to toner adhesion to the fixing cleaning roller, the glass transition point of the adhering toner is about 5 to 15 ° C. lower than that of the pulverized toner, and the toner adhering to the cleaning roller does not adhere to the fixing roller during copying. Melt by heat and reverse transfer to fixing roller.

  Therefore, the present inventors have not changed the toner configuration having a core-shell structure, and have achieved both low-temperature fixability, storage stability, hot offset property, and toner dissolution from the cleaning roller of the fixing roller, and further high-definition images. Developed a toner that also made it possible.

  That is, a toner obtained by removing an organic solvent contained in a dispersion liquid in which fine droplet particles containing at least an organic solvent, a binder resin, and a colorant are dispersed in an aqueous medium containing resin fine particles. The glass transition point (Tg) of the toner at that time is 30 to 46 ° C., and the glass transition point (Tg) of the resin fine particles coated on the toner surface is 50 to 70 ° C. A dry toner having a 1/2 outflow temperature of 95 to 120 ° C. when masticated with a plastmill and a 1/2 outflow temperature of 120 to 145 ° C. before mastication hardly causes toner dissolution and In addition, it has become possible to provide a toner that satisfies the low temperature fixing property and the hot offset property.

Since the resin fine particles adhering to the toner surface are harder than the resin inside the toner, when the thermal characteristics are measured with a flow tester, the resin particles adhering to the surface are affected and proper evaluation cannot be performed. Accordingly, proper evaluation can be performed by kneading with a constant energy and destroying the resin fine particle layer on the surface to measure the thermal characteristics of the toner layer inside the particle. As a condition for masticating the toner with Laboplast Mill, if the shear energy is high, not only the resin particles on the surface of the toner particles but also the toner layers inside the toner particles are cut into the resin molecules, and the thermal characteristics of the toner layer inside the toner Measurement cannot be performed. If the shear energy is weak, it is not evaluated due to the influence of resin fine particles on the surface. Accordingly, the conditions for kneading with a lab plast mill are such that the resin fine particle layer on the toner surface is broken, but the toner layer inside the toner particles is not broken. For example, the evaluation is performed under the following conditions.
Laboplast mill kneading conditions:
Mixer: R60
Temperature: 130 ° C
Time: 15 minutes
Sample amount: 45g
Mixer rotation speed: 50 RPM
The pulverized toner does not need to be masticated because there are no resin particles on the surface. However, the toner having the core / shell structure of the present invention is affected by the surface of the toner when used in a copying machine. This evaluation is necessary because the thermal characteristics inside the toner greatly affect the fixing quality.

  If the ½ outflow temperature after mastication with a lab plast mill is less than 95 ° C, the hot offset or the fixing cleaning roller is likely to be melted out. If it exceeds 120 ° C, the melt out is improved. Low temperature fixability is not satisfactory. The value of the flow tester before kneading is a range for obtaining the optimum value after kneading. If this value is not satisfied, it is difficult to achieve both low-temperature fixability and hot offset property.

  Further, when the THF insoluble content contained in the toner is 5 to 25% by weight, the toner adhering to the cleaning roller has high elasticity, and even if the temperature of the cleaning roller rises, it is difficult to dissolve. With regard to melting out, it is difficult for conventional toners to have a Tg of about 55 ° C. or less from the viewpoint of storage stability. Therefore, the toner adhering to the cleaning roller of the fixing roller is high because the resin component having a relatively high Tg adheres. Since the toner became a softening point toner, it was difficult to melt even when the roller temperature increased, and the technical problems were low. However, since the pseudo-capsule toner allows fixing at a lower temperature, the toner inside the particles uses a low Tg component resin, so the toner that adheres to the fixing roller adheres to the low Tg component toner. Therefore, it is easy for melting from the cleaning roller to occur, and it tends to be a trade-off with low-temperature fixing. The reason for eliminating this is as follows.

  As a result of examining the toner adhering to the fixing cleaning roller, the inventors have found that the adhering toner has a remarkably small amount of the wax composition initially added, and the molecular weight distribution of the adhering toner is measured by GPC. It was found that the polymer side component was attached. Therefore, the toner component to be fixed is considered to be a low molecular component having an affinity for paper. The reason is presumed below.

In a heat fixing apparatus that fixes a toner image on a recording medium while being conveyed through the recording medium between a heating member and a pressure member, the toner to be fixed adheres to a minute amount of superheated roller. The toner that adheres is a component that does not contain wax in the particles, or a toner component that cannot be fixed with a highly elastic component. As a condition that no melting from the fixing cleaning roller occurs, 1. 1. The amount attached to the roller is as small as possible. 2. The adhering toner is a high molecular component of the toner, and is less likely to dissolve than when a high softening point component or a highly elastic component is adhered. 3. Toner in which wax is uniformly dispersed in toner particles is difficult to adhere to the cleaning roller. In the particle size distribution, the sharper the distribution, the more uniformly heat is applied to the toner, the less toner adheres to the toner, and the less the toner adheres to the fixing cleaning roller.

  It is presumed that fixing to paper in roller fixing and belt fixing starts at around 70 ° C. to 100 ° C. in copiers, printers, fax machines, etc., in which the toner fixing effective temperature is now energy-saving. In order to allow the toner to melt, the toner must start to flow around this temperature, so that the toner must soften and start fixing at least at about 90 to 110 ° C.

  However, in order to soften at 90 ° C., the glass transition must be 46 ° C. or less from the storage data, but the Tg (glass transition point) of such a polymer is also related to the molecular weight. Usually, when the glass transition point is 46 ° C. or lower, the fixability is good, but the preservability is not satisfied.

  In the toner of the present invention, the toner Tg is designed with a very low temperature binder of 30 to 46 ° C., and resin fine particles having a glass transition at 50 to 70 ° C. are 0.3 to 2.2. 0% by weight is present. The particles uniformly coated on the toner particles become pseudo-capsule constituting particles that protect the heat against the low-softening binder. The reason for the effects on hot offset, low-temperature fixability, and heat-resistant storage is that the binder resin on the toner surface has a high molecular weight due to a urea bond obtained by reacting a prepolymer and amines, and part of the surface has a network structure. It has a three-dimensional structure that is relatively resistant to stress. Furthermore, while using the same heat characteristics as the conventional toner for the particle surface layer, the inside uses a low Tg polyester resin as a toner binder, so it is advantageous in terms of low-temperature fixability compared to uniformly kneaded pulverized toner. (This toner particle model is shown in FIG. 2). The resin fine particles coated on the surface layer must react quickly with the heat capacity of the heating roller at the time of fixing, and the toner particle binder must be oozed out of the surface layer. The balance between heat-resistant storage and the amount of toner squeezed is controlled by the amount of resin fine particles adhering. The fine resin particles remaining in the toner have a particle size of 10 to 200 nm, and the amount of the fine resin particles is 0.3 to 2% by weight. If the particle diameter is less than 10 nm, it is difficult to obtain resin fine particles. If the particle diameter exceeds 200 nm, it remains thick on the surface layer and the fixability deteriorates. As for the toner Tg, 30 to 46 ° C. is effective as a range capable of low-temperature fixing. If it is less than 30 ° C., it is difficult to form particles, and if it exceeds 46 ° C., the effect for low-temperature fixing is lost.

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

  In the present invention, the weight average particle diameter (Dv) of the toner is 3.0 to 6.0 μm, and the ratio (Dv / Dn) to the number average particle diameter (Dn) is 1.00 ≦ Dv / Dn ≦ 1. .20, it becomes possible to obtain high-resolution and high-quality toner. Thereby, it can be excellent in all of heat resistant storage stability, low-temperature fixability, and hot offset resistance. In particular, in order to ensure low-temperature fixability, Tg has been lowered, but there has been a limit from the relationship with storage stability, so it was possible to achieve further low-temperature fix by reducing the particle size. On the other hand, when many particles having a particle size of 8 μm or more are contained, not only fixing property but also gradation property are inhibited. If the quality is 2% by weight or less, no major obstacles occur. Furthermore, in a two-component developer, even if the toner balance for a long time is performed, fluctuations in the particle size of the toner in the developer are reduced, and good and stable developability can be obtained even with long-term stirring in the developing device. It is done. In general, it is said that the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning properties. is there.

  When the volume average particle size is smaller than the range in the present invention, in the case of a two-component developer, the toner is fused to the surface of the carrier during a long period of stirring in the developing device, and the charging ability of the carrier is lowered, When it is used, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur.

  In addition, these phenomena are greatly related to the particle size distribution with a particle size of around 3 μm. Especially when the particle size of 3 μm or less by the Coulter method exceeds 2% by weight, the adhesion to the carrier and the stabilization of charging at a high level are achieved. It becomes a hindrance when trying to improve sex. In addition, the cleaning performance is significantly reduced along with the shape.

  On the contrary, when the weight average particle diameter of the toner is larger than the range defined by the present invention of 6.0 μm, it becomes difficult to obtain a high-resolution and high-quality image, and the balance of the toner in the developer is reduced. In many cases, the variation in the particle diameter of the toner increases. It was also clarified that the same was true when the weight average particle diameter / number average particle diameter was larger than 1.20.

  The average particle size and the particle size distribution of the toner can be measured using a measuring device for measuring the particle size distribution of toner particles by a car Coulter counter method. Examples of the measuring device include a Coulter counter TA-II and a Coulter multisizer IIe (whichever Also manufactured by Coulter). In the present invention, a Coulter counter TA-II type was used, and the number distribution and volume distribution interface (Nichiken Giken) and PC9801 personal computer (NEC) were connected and measured.

The measurement method is described below.
First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using first grade sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as an aperture. Volume distribution and number distribution are calculated. The measurement range of the toner particle size distribution is 2.00 μm to 40, less than 30 μm.

  As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm. The volume-based weight average particle diameter (Dv) obtained from the volume distribution according to the present invention and the number average particle diameter (Dn) obtained from the number distribution and the ratio Dv / Dn (D4) were obtained.

The molecular weight distribution of the toner binder component is measured by the following method. After about 1 g of toner is carefully evaluated in an Erlenmeyer flask, 10 to 20 g of THF (tetrahydrofuran) is added to obtain a THF solution having a binder concentration of 5 to 10%. The column is stabilized in a heat chamber at 40 ° C., and THF as a solvent is allowed to flow through the column at this temperature at a flow rate of 1 ml / min, and 20 μl of the THF sample solution is injected. The molecular weight of the sample is calculated from the relationship between the retention value and the logarithmic value of a calibration curve prepared from a monodisperse polystyrene standard sample. A calibration curve is created using a polystyrene standard sample. As a monodisperse polystyrene standard sample, the thing of the range of molecular weight 2.7 * 10 < ² > -6.2 * 10 < ⁶ > by Tosoh Corporation is used, for example. A refractive index (RI) detector is used as the detector. As the column, for example, TSKgel, G1000H, G2000H, G2500H, G3000H, G4000H, G5000H, G6000H, G7000H, GMH manufactured by Tosoh Corporation are used in combination.

  The molecular weight distribution of the THF soluble component has a main peak molecular weight of usually 2500 to 10,000, preferably 2500 to 8000, and more preferably 2500 to 6000. When the amount of the component having a molecular weight of less than 1000 increases, the heat resistant storage stability tends to deteriorate, and when the component having a molecular weight of 15000 or more increases, the low-temperature fixability tends to decrease. However, the decrease can be suppressed as much as possible by balance control. The content of components having a molecular weight of 30000 or more is 1 to 10%, and varies depending on the toner material, but preferably 3 to 6%.

  The number average molecular weight of the THF-soluble component has a molecular weight distribution in the range of 1500 to 15000, and if it is 1500 or less, it is difficult to control the particle dispersion during pigment dispersion and emulsification, and there is a problem in wax dispersibility, which exceeds 15000. It is difficult to become particles.

(Circularity and spindle shape)
The shape and number-based particle size distribution of the dry toner of the present invention are measured by, for example, a flow particle image analyzer FPIA-2100 (manufactured by Sysmex Corporation). The particle size distribution represented by the flow type particle image analyzer is more accurate in measuring particles of 2 μm or less than the Coulter method. The shape is represented by circularity. A method for measuring the circularity will be described later. Since the circularity is a value obtained by dividing the circumference of the equivalent circle equal to the projected area of the toner particles by the circumference of the actual particles, the circularity of the true circle is accordingly 1.000. It is. As the value decreases from 1, it becomes a spindle shape (ellipse). The average circularity of the toner of the present invention is 0.900 to 0.960, and the spindle shape shown in the SEM photograph of FIG. 8 is preferable. A toner having an average circularity of less than 0.900 has an irregular shape, and satisfactory transferability and high-quality images without dust cannot be obtained. The irregularly shaped particles have many points of contact with the smooth medium on the photoconductor and the like, and the electric charge concentrates on the tip of the protrusion, so that the van der Waals force and the mirror image force are higher than those of the relatively spherical particles. For this reason, in the electrostatic transfer process, the spherical particles are selectively moved in the toner in which the amorphous particles and the spherical particles are mixed, and the character portion and the line portion image are lost. Further, the remaining toner has to be removed for the next development process, and there is a problem that a cleaner device is necessary and the toner yield (the ratio of toner used for image formation) is low. The circularity of the pulverized toner is usually 0.910 to 0.920 when measured with this apparatus. A specific method for measuring the circularity is shown below.

As a method for measuring the shape, an optical detection band method is suitable in which a suspension containing particles is passed through an imaging unit detection band on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. The circularity is a value obtained by dividing the perimeter of an equivalent circle having the same projected area obtained by this method by the perimeter of the actual particle. This value can be measured as an average circularity by the flow type particle image analyzer FPIA-2100. As a specific measuring method, 0.1 to 0.5 ml of a surfactant, preferably alkylbenzene sulfonate, is added as a dispersing agent to 100 to 150 ml of water from which impure solids have been removed in advance in a container. Add about 0.1-0.5g of sample. The suspension in which the sample is dispersed is obtained by performing a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and measuring the shape and particle size distribution of the toner with the above apparatus at a dispersion concentration of 3000 to 10,000 / μl. It is done.
For the particle size distribution based on the number, a value of particles having a small particle ratio in the range of 0.6 to 2 μm is used.
The average circularity is an average value of particles of 0.40 to 1.00.

(Glass transition point)
The measuring method of the glass transition point Tg will be outlined. As an apparatus for measuring Tg, a TG-DSC system TAS-100 manufactured by Rigaku Corporation was used.
First, about 10 mg of a sample is placed in an aluminum sample container, which is placed on a holder unit and set in an electric furnace. First, after heating from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 min, the sample was cooled to room temperature and left for 10 min, and the temperature rising rate was again increased to 150 ° C. under a nitrogen atmosphere. DSC measurement was performed with heating at min. Tg was calculated from the tangent of the endothermic curve near the Tg and the base line using the analysis system in the TAS-100 system.

(Toner production method)
The toner of the present invention removes an organic solvent contained in a dispersion liquid in which fine droplet particles containing at least an organic solvent, a binder resin, a colorant, and a wax are dispersed in an aqueous medium containing resin fine particles. It is a toner obtained by doing this. More specifically, a modified polyester resin capable of reacting with at least a compound having an active hydrogen group, a colorant, and a wax are dissolved or dispersed in an organic solvent, and the dissolved or dispersed substance is present in the presence of resin fine particles in an aqueous medium. It is a toner obtained by dispersing fine particles in the lower layer, causing a polyaddition reaction with a compound having an active hydrogen group, and removing the solvent of the obtained dispersion.
In order to obtain the toner particle structure shown in FIG. 2, it is necessary to suppress the range of Tg and molecular weight of the polyester resin used. In other words, the polyester inside the particles has a Tg of 30 ° C. to 46 ° C. and a molecular weight of 1500 to 15000 in terms of number average molecular weight, the inside of the particles is a low softening point polymer, and the resin is ureaized with a prepolymer to give the particles elasticity. The inside of the particle can be designed by dispersing. As a specific example, as a modified polyester resin capable of reacting with a compound having an active hydrogen group, a polyester prepolymer (A) having an isocyanate group is used, and as a compound having an active hydrogen group, amines (B) are used. Can be mentioned. Examples of the polyester prepolymer (A) having an isocyanate group include a polycondensate of a polyol (PO) and a polycarboxylic acid (PC) and a polyester having an active hydrogen group that is further reacted with a polyisocyanate (PIC). Can be mentioned. Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.

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

  Examples of the polycarboxylic acid (PC) include dicarboxylic acid (DIO) and tricarboxylic or higher polycarboxylic acid (TC), and (DIO) alone and a mixture of (DIO) and a small amount of (TC) are preferable. Dicarboxylic acids (DIO) include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, naphthalene) Dicarboxylic acid and the like). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polycarboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polycarboxylic acid (PC), you may make it react with a polyol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

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

  As polyisocyanate (PIC), aliphatic polyisocyanate (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanate (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic Diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ″, α ″ -tetramethylxylylene diisocyanate, etc.); isocyanurates; Those blocked with caprolactam or the like; and combinations of two or more of these.

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

  The number of isocyanate groups contained per molecule in the prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average. It is. If the number is less than 1 per molecule, the molecular weight of the urea-modified polyester becomes low, and the 1/2 outflow temperature after lab plastmill kneading decreases.

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

  Furthermore, if necessary, the molecular weight of the 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 (B) is the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). The ratio is usually 2/1 to 1/2, preferably 1.5 / 1 to 1 / 1.5, and more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] is more than 2 or less than 1/2, the molecular weight of the polyester is lowered and the hot offset resistance is deteriorated. In the present invention, urea-modified polyester (UMPE) can be used as the polyester-based resin (polyester), but the polyester may contain a urethane bond as well as a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

  The weight average molecular weight of urea-modified polyester (UMPE) is usually 10,000 or more, preferably 20,000 to 10,000,000, and more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates.

  In the present invention, the polyester modified with a urea bond (UMPE) is not limited to being used alone, and it is preferable to include an unmodified polyester (PE) as a toner binder component. The combined use of (PE) improves low-temperature fixability and gloss when used in a full-color device, and is more preferable than single use. Examples of (PE) include polycondensates of polyol (PO) and polycarboxylic acid (PC) similar to the polyester component of (UMPE), and (PE) is not only unmodified polyester. These may be modified with chemical bonds other than urea bonds, and may be modified with urethane bonds, for example. (UMPE) and (PE) are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, the polyester component of (UMPE) and (PE) preferably have similar compositions. When (PE) is contained, the weight ratio of (UMPE) to (PE) is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, Particularly preferred is 7/93 to 20/80. When the weight ratio of (UMPE) is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

The hydroxyl value of (PE) is preferably 5 or more.
The acid value of (PE) is usually 1 to 30, preferably 5 to 20. By giving an acid value, it tends to be negatively charged, and further, the affinity between the paper and the toner is good when fixing to paper, and the low-temperature fixability is improved. However, when the acid value exceeds 30, there is a tendency to deteriorate with respect to the stability of charging, particularly the environmental fluctuation. In the polyaddition reaction, if the acid value is touched, it will lead to shaking in the granulation process, making it difficult to control the emulsification.

(Emulsification method in aqueous medium)
The aqueous medium used in the present invention may be water alone, or a solvent miscible with water may be used in combination. Examples of the miscible solvent include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.

  Toner particles are reacted with a dispersion made of a prepolymer (A) having an isocyanate group and amines in an aqueous medium. As a method for stably forming a dispersion using the prepolymer (A), a composition of a toner raw material composed of urea-modified polyester (UMPE) or prepolymer (A) is added to an aqueous medium, and dispersed by shearing force. The method of making it, etc. are mentioned. The prepolymer (A) and other toner compositions (hereinafter referred to as toner raw materials), a colorant masterbatch, a wax, a charge control agent, an unmodified polyester resin, and the like form a dispersion in an aqueous medium. However, it is more preferable to mix the toner raw materials in advance and then add and disperse the mixture in the aqueous medium.

  The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. Moreover, in order to make the particle size of a dispersion 2-20 micrometers, a high-speed shearing type is preferable. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. As the temperature at the time of dispersion, however, the dispersion temperature is usually 20 ° C. or less and preferably 30 to 60 minutes. This is to prevent aggregation of the pigment. The amount of the aqueous medium used is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight, based on 100 parts of the toner composition containing the modified polyester and prepolymer (A). If the amount is less than 50 parts by weight, the dispersion state of the toner composition is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 2000 parts by weight, it is not economical. Further, the viscosity of the oil phase at this time needs to be 2000 mP · s or more with a B-type viscometer. When the viscosity of the oil phase is less than 2000 mP · s, the pigment particles easily move in the dispersed oil phase and start to aggregate, so that the pigment dispersibility of the toner deteriorates and the volume specific resistance of the toner decreases. If the temperature is not maintained at 15 ° C. or lower even after the pigment is dispersed, the pigment particles tend to aggregate.

  Moreover, a dispersing agent can also be used as needed. It is preferable to use a dispersant because the particle size distribution becomes sharp and the dispersion is stable.

  Furthermore, in order to lower the viscosity of the toner composition as the organic solvent, a solvent in which the urea-modified polyester (UMPE) or the prepolymer (A) having an isocyanate group is soluble can be used. The use of a solvent is preferable in that the particle size distribution becomes sharp. The solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal. Examples of the solvent include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, Methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. The usage-amount of the solvent with respect to 100 parts of prepolymers (A) is 0-300 parts normally, Preferably it is 0-100 parts, More preferably, it is 25-70 parts. When a solvent is used, it is removed by heating under normal pressure or reduced pressure after elongation and / or crosslinking reaction.

  The elongation and / or cross-linking reaction time is selected depending on the reactivity of the isocyanate group structure of the prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. is there. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

(Desolvation process)
In order to remove the organic solvent from the obtained emulsified dispersion, a method can be employed in which the temperature of the entire system is gradually raised and the organic solvent in the droplets is completely evaporated and removed. The toner circularity can be controlled by the strength of the liquid agitation before the solvent removal and the solvent removal time. By slowly removing the solvent, the shape becomes more spherical, and when it is expressed by a circularity, it becomes 0.980 or more, and by removing the solvent with strong stirring in a short time, it becomes irregular or irregular, and expressed by a circularity. 0.900 to 0.960. The degree of circularity can be controlled by demulsifying the emulsified liquid that has been emulsified and dispersed in an aqueous medium, followed by elongation reaction, while stirring with a strong stirring force of 30 to 50 ° C in a stirring tank. Thus, shape control in the range of 0.850 to 0.990 is possible. This is thought to be due to volumetric shrinkage caused by abrupt solvent removal during the solvent removal of ethyl acetate contained in the granulation, and the shape can be controlled by stirring force and time. However, the solvent removal time at this time shall be within 1 hour. When the time is longer than 1 hour, pigment aggregation starts and the volume resistivity decreases.

  It is also possible to spray the emulsified dispersion in a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, and to evaporate and remove the aqueous dispersant together. As a dry atmosphere in which the emulsified dispersion is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, or the like, in particular, various air currents heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used is generally used. Sufficient quality can be obtained with a short treatment such as spray dryer, belt dryer or rotary kiln.

  When the particle size distribution at the time of emulsification dispersion is wide and washing and drying processes are performed while maintaining the particle size distribution, the particle size distribution can be adjusted by classification into a desired particle size distribution.

  In the classification operation, the fine particle portion can be removed in the liquid by a cyclone, a decanter, centrifugation, or the like. Of course, the classification operation may be performed after obtaining the powder after drying, but it is preferably performed in a liquid in terms of efficiency. The unnecessary fine particles or coarse particles obtained can be returned to the kneading step and used for the formation of particles. At that time, fine particles or coarse particles may be wet.

  The dispersant used is preferably removed from the obtained dispersion as much as possible, but it is preferable to carry out it simultaneously with the classification operation described above.

  The resulting dried toner powder is mixed with different kinds of particles such as charge control fine particles and fluidizing agent fine particles, or fixed and fused on the surface by applying mechanical impact force to the mixed powder. It is possible to prevent the dissociation 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 the pulverization air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron Examples include a system (manufactured by Kawasaki Heavy Industries, Ltd.) and an automatic mortar.

(Coloring agent)
As the coloring agent of the present invention, known dyes and pigments can be used, such as carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, Ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G) , R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Fayce Red, Parachlor Ortoni Roaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake , Thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolone , Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine Blue, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Fu Talocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant used in the present invention can also be used as a master batch combined with a resin. As the binder resin to be kneaded together with the production of the masterbatch or the masterbatch, in addition to the above-mentioned modified and unmodified polyester resins, styrene such as polystyrene, poly p-chlorostyrene, and polyvinyltoluene, and polymers of substitution products thereof. Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Polymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α -Methyl chloromethacrylate copolymer, styrene -Acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid Styrenic copolymers such as ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacryl Examples include acid resins, rosins, modified rosins, terpene resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, and paraffin waxes, which can be used alone or in combination.

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

(wax)
The dry toner of the present invention contains a wax together with a toner binder and a colorant. Known waxes can be used, and examples thereof include polyolefin waxes (polyethylene wax, polypropylene wax, etc.); long-chain hydrocarbons (paraffin wax, sazol wax, etc.); carbonyl group-containing waxes, and the like. Of these, carbonyl group-containing waxes are preferred. Carbonyl group-containing waxes include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18. -Octadecandiol diol distearate, etc.); polyalkanol esters (tristearyl trimellitic acid, distearyl maleate, etc.); polyalkanoic acid amides (ethylene diamine dibehenyl amide, etc.); polyalkylamides (trimellitic acid tristearyl amide, etc.) And dialkyl ketones (such as distearyl ketone). Among these carbonyl group-containing waxes, polyalkanoic acid esters are preferred. The melting point of the wax of the present invention is usually 40 to 160 ° C, preferably 50 to 120 ° C, more preferably 60 to 90 ° C. A wax having a melting point of less than 40 ° C. has an adverse effect on heat resistant storage stability, and a wax having a melting point of more than 160 ° C. tends to cause a cold offset when fixing at a low temperature. Further, the melt viscosity of the wax is preferably 5 to 1000 cps, more preferably 10 to 100 cps as a measured value at a temperature 20 ° C. higher than the melting point. Waxes exceeding 1000 cps have poor effects for improving hot offset resistance and low-temperature fixability. The content of the wax in the toner is usually 1 to 20% by weight, preferably 3 to 10% by weight. In particular, in order to finely disperse the wax in the particles having a small particle size, the content of the wax is preferably maintained at 3 to 7% by weight.

(Charge control agent)
The toner of the present invention may contain a charge control agent as necessary. 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 salts). Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Nitronine-based dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E- 84, E-89 of a phenol-based condensate (manufactured by Orient Chemical Industry Co., Ltd.), TP-302 of a quaternary ammonium salt molybdenum complex, TP-415 (manufactured by Hodogaya Chemical Industry Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, quinacridone Azo pigments, sulfonate group, carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

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

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

  In addition, polymer fine particles, such as polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization, methacrylate esters, acrylate copolymers, polycondensation systems such as silicone, benzoguanamine, and nylon, thermosetting Examples thereof include polymer particles made of a resin.

  Such a fluidizing agent performs surface treatment to increase hydrophobicity, and can prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having an alkyl fluoride group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferable surface treatment agents. .

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

(Resin fine particles)
It is important that the resin fine particles used in the present invention have a glass transition point (Tg) of 50 to 70 ° C., and a weight average molecular weight of 100,000 to 300,000 is preferable.
When the glass transition point is less than 50 ° C., toner blocking is reduced, and when it exceeds 70 ° C., softening of toner particles during fixing is hindered.
The resin fine particles adhere to the outermost surface of the toner particles after emulsification and have a toner structure that prevents blocking of the low softening polymer inside the particles. The resin fine particles may be spherical as shown in FIG. 2 or may be indefinite. Further, it may be layered so as to exist as a film on the toner surface due to the influence of the organic solvent or the influence of the subsequent toner production process.

  As the resin fine particles, any resin fine particles can be used as long as they form an aqueous dispersion and have the above thermal characteristics range. For example, vinyl resin, polyurethane resin, epoxy resin, polyester resin, and the like can be given. As the resin fine particles, two or more of the above resins may be used in combination. Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferred because an aqueous dispersion of fine spherical resin particles is easily obtained.

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

(Carrier for two components)
When the toner of the present invention is used for a two-component developer, it may be used by mixing with a magnetic carrier, and the content ratio of the carrier and the toner in the developer is 1 to 10 weights of toner with respect to 100 parts by weight of the carrier. Part is preferred. As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used. Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride And fluoro such as terpolymers of non-fluoride monomers including, and silicone resins. Moreover, you may contain electrically conductive powder etc. in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.

  The toner of the present invention can also be used as a one-component magnetic toner that does not use a carrier or a non-magnetic toner.

(Image forming device)
In the image forming apparatus of the present invention, the photosensitive member is rotationally driven at a predetermined peripheral speed. In the rotation process, the photosensitive member is uniformly charged with a positive or negative predetermined potential on its peripheral surface by the charging unit, and then receives image exposure light from an image exposing unit such as slit exposure or laser beam scanning exposure. An electrostatic latent image is sequentially formed on the peripheral surface of the body, and the formed electrostatic latent image is then developed with toner by a developing unit, and the developed toner image is transferred between the photosensitive member and the transfer unit from the paper feeding unit. Then, the image is sequentially transferred to the transfer material fed in synchronization with the rotation of the photosensitive member by the transfer means. The transfer material that has received the image transfer is separated from the surface of the photosensitive member, introduced into the image fixing means, and fixed on the image, and printed out as a copy (copy). The surface of the photoconductor after the image transfer is cleaned by removing toner remaining after transfer by a cleaning unit, and after being further neutralized, it is repeatedly used for image formation.

  Hereinafter, an example of the image forming apparatus of the present invention will be described with reference to the drawings. FIG. 4 shows an overall schematic configuration of an image forming apparatus that includes the dry toner or developer of the present invention and includes the thermal fixing device according to the present invention. Reference numeral 100 in the drawing denotes a copying machine main body. The copying machine main body 100 has an image reading device 200 mounted thereon and placed on a sheet bank 300. An automatic document feeder 400 is mounted on the image reading apparatus 200 so as to be opened and closed up and down with the back side as a fulcrum.

The copying machine main body 100 is provided with a drum-shaped photoreceptor 10 as an image carrier. Around the photoconductor 10, in order from the charging device 11 arranged on the left side in the figure in the rotation direction (counterclockwise) A of the photoconductor 10, the developing device 12 is on the lower side, the transfer device 13 is on the right side, and the transfer device 13 is on the upper side. A cleaning device 14 is arranged.
Among them, the developing device 12 uses the toner of the present invention as the toner, and attaches the toner using a developing roller to make the electrostatic latent image on the photoreceptor 10 visible.

Further, the transfer device 13 is configured by winding a transfer belt 17 between upper and lower rollers 15 and 16 and pressing the transfer belt 17 against the peripheral surface of the photoconductor 10 at a transfer position B.
In FIG. 4, what is provided on the left side of the charging device 11 and the cleaning device 14 is a toner supply device 20 for supplying new toner to the developing device 12.

In addition, a sheet conveying apparatus C that conveys a sheet S sent from a sheet cassette 61 (described later) of the sheet bank 300 from below to the stack position via the transfer position B is provided inside the copying machine main body 100. The sheet conveying apparatus C includes a supply path R1, a manual feed path R2, and a sheet conveyance path R.
In the sheet conveyance path R, a registration roller 21 is provided at an upstream position of the photoconductor 10. Further, a thermal fixing device 22 is provided at a downstream position of the photoconductor 10. Specifically, the heat fixing device 22 described later is provided with a heating roller (heating member) 30 and a pressure roller (pressure member) 32.

  Further downstream of the heat fixing device 22, a discharge branch claw 34, a discharge roller 35, a first pressure roller 36, a second pressure roller 37, and a waist roller 38 are provided. Further, a discharge stack portion (discharge position) 39 for stacking sheets on which images have been formed is provided at the end.

  The copying machine main body 100 is provided with a switchback device 42 on the right side in the drawing. The switchback device 42 branches from the position of the discharge branch pawl 34 of the sheet conveyance path R and leads to the switchback position 44 including the pair of switchback rollers 43, and again from the switchback position 44, the sheet conveyance path. A sheet conveying apparatus D having a re-conveying path R4 leading to the R registration rollers 21 is provided. The sheet conveying apparatus D includes a plurality of sheet conveying rollers 66 for conveying the sheet.

A laser writing device 47 is provided on the left side of the developing device 12 in the drawing. The laser writing device 47 is provided with a laser light source (not shown), a scanning polygon mirror 48, a polygon motor 49, a scanning optical system 50 such as an fθ lens, and the like.
The image reading apparatus 200 is provided with a light source 53, a plurality of mirrors 54, an imaging optical lens 55, an image sensor 56 such as a CCD, and the like. A contact glass 57 is provided on the upper surface.

  The automatic document feeder 400 on the contact glass 57 is provided with a document setting table (not shown) at the document placement position and a document stack table (not shown) at the discharge position. In addition, a sheet conveyance device having a document conveyance path (not shown) that conveys a document sheet from a document setting table to a document stacking table through a reading position on the contact glass 57 of the image reading device 200 is provided. The sheet conveying apparatus includes a plurality of sheet conveying rollers (not shown) that convey the original sheet.

  The sheet bank 300 includes therein a plurality of sheet cassettes 61 for storing sheets S such as sheets and OHP films as recording media. Each sheet cassette 61 is provided with a call roller 62, a supply roller 63, and a separation roller 64, respectively. The above-described supply path R1 leading to the sheet conveyance path R of the apparatus main body 100 is formed on the right side of the multi-stage sheet cassette 61 in the drawing. The supply path R1 is also provided with several sheet transport rollers 66 (sheet transport rotating body) for transporting the sheet.

  The copying machine main body 100 is provided with a manual feed unit 68 on the right side in the drawing. A manual feed tray 67 is provided in the manual feed unit 68 so as to be openable and closable, and includes the above-described manual feed path R <b> 2 that guides a manual sheet set on the manual feed tray 67 to the sheet conveyance path R. Similarly, the manual feed tray 67 is provided with a calling roller 62, a supply roller 63, and a separation roller 64.

Now, when making a copy using this copying machine, a main switch (not shown) is turned on and a document is set on a document setting table of the automatic document feeder 400. In the case of a book document, the automatic document feeder 400 is opened, a document is set directly on the contact glass 57 of the image reading device 200, and the automatic document feeder 400 is closed and pressed.
When a start switch (not shown) is pressed, when a document is set on the automatic document feeder 400, the document is moved onto the contact glass 57 through the document conveyance path by the sheet conveyance roller, and then the image reading device 200 is moved. Drives, reads the document content, and discharges it onto the document stacking table. On the other hand, when the document is set directly on the contact glass 57, the image reading apparatus 200 is immediately driven.

When the image reading apparatus 200 is driven, the image reading apparatus 200 moves the light source 53 along the contact glass 57, reflects light from the light source 53 on the original surface on the contact glass 57, and reflects the reflected light to a plurality of light sources 53. The light is reflected by a mirror 54, passes through an imaging optical lens 55, is put in an image sensor 56, and the image content is read by the image sensor 56.
At the same time, the photoconductor 10 is rotated by a photoconductor drive motor (not shown). First, in the illustrated example, the surface is uniformly charged by the charging device 11 using a charging roller, and then the above-described image reading device 200 is used. The laser writing device 47 irradiates a laser beam in accordance with the content of the read document and writes it with the laser writing device 47 to form an electrostatic latent image on the surface of the photosensitive member 10. Visualize the electrostatic latent image.

  At the same time when the start switch is pressed, the sheet S is sent out from the sheet cassette 61 corresponding to the selected size in the plurality of sheet cassettes 61 provided in multiple stages in the sheet bank 300 by the calling roller 62, and the subsequent supply roller 63 is separated. While being separated and conveyed one by one by the roller 64, the sheet is put into the supply path R 1, conveyed by the sheet conveying roller 66 to the sheet conveying path R, and abutted against the registration roller 21 and stopped. Then, the registration roller 21 is rotated in synchronization with the rotation of the toner image visualized on the photosensitive member 10 described above, and is sent to the right side of the photosensitive member 10.

  Alternatively, the manual feed tray 67 of the manual feed unit 68 is opened, the manual sheet set on the manual feed tray 67 is sent out by the calling roller 62, and separated and conveyed one by one by the subsequent supply roller 63 and separation roller 64. The sheet is fed into the manual feed path R2, is conveyed by the sheet conveyance roller 66, is guided to the sheet conveyance path R, and is similarly fed to the right side of the photosensitive member 10 by the registration roller 21 in synchronization with the rotation of the photosensitive member 10.

  Then, the toner image on the photoconductor 10 is transferred to the sheet S fed to the right side of the photoconductor 10 at the transfer position B by the transfer device 13 in the illustrated example to form an image. Residual toner on the photoconductor 10 after image transfer is removed and cleaned by a cleaning device 14, and a residual potential on the photoconductor 10 is removed by a neutralization device (not shown) to prepare for the next image formation starting from the charging device 11. .

  On the other hand, the sheet S after the image transfer is conveyed by the transfer belt 17 and put into the heat fixing device 22 and is conveyed through the heating roller 30 and the pressure roller 32 while applying heat and pressure to the sheet S. Fix the upper toner image. Thereafter, the sheet is seated by the discharge roller 35, the first pressure roller 36, the second pressure roller 37, and the waist roller 38, discharged onto the discharge stack portion 39, and stacked there.

  Note that the discharge branch claw 34 is switched when images are transferred to both sides of the sheet. Then, the sheet having the toner image transferred to the surface is transferred from the sheet conveying path R to the reversing path R3, conveyed by the sheet conveying roller 66 to the switchback position 44, and switched back by the switchback roller 43 to be re-conveyed. Inverted in the path R4, transported by the sheet transport roller 66, guided again to the sheet transport path R, and the image is transferred to the back surface of the sheet in the same manner as described above.

The thermal fixing device used in the present invention is a thermal fixing device that fixes a toner image on a recording medium while being conveyed between the heating member 30 and the pressure member 32 as shown in FIG. The cleaning member 74 for removing the toner adhering to the toner is provided, and the surface pressure (roller load / contact area) applied between the heating member and the pressure member is 1.5 × 10 ⁵ Pa or less. If the surface pressure is increased, the release width of fixing and hot offset becomes wider, but it becomes easier to wrinkle paper by applying a strong pressure. The cleaning member 74 is not limited to the case where the toner adhering to the heating member 30 or the pressure member 32 is directly pressed against the heating member 30 or the pressure member 32, but the toner removing member 84 that presses against the pressure member 32 as shown in FIG. The toner adhering to the pressure member 32 may be removed, and although not shown, the toner adhering to the heating member 32 is removed via the toner removing member 84 pressed against the heating member 30. It may be a thing.

(Process cartridge)
FIG. 6 shows a schematic configuration of an example of the process cartridge of the present invention having a photosensitive member, a charging unit, a developing unit, and a cleaning unit, and the developing unit having the dry toner of the present invention. FIG. 7 shows a schematic configuration of an example of a process cartridge having the two-component developer of the present invention.
In the present invention, among the constituent elements such as the above-mentioned photoreceptor, charging device means, developing means, and cleaning means, a plurality of them are integrally combined as a process cartridge, and this process cartridge is configured as a copying machine, a printer, or the like. The image forming apparatus main body is detachable.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to this. Hereinafter, a part shows a weight part.

Production Example 1
(Synthesis of resin fine particle emulsion)
In a reaction vessel equipped with a stir bar and a thermometer, water 838 parts, sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 73 parts of styrene, 92 parts of methacrylic acid, When 130 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion 1] was obtained. The volume average particle diameter of [resin fine particle dispersion 1] measured by LA-920 was 90 nm. A portion of [resin fine particle dispersion 1] was dried to isolate the resin component. The Tg of the resin was 57 ° C., and the weight average molecular weight was 200,000.

Production Example 2
(Adjustment of aqueous phase)
990 parts of water, 83 parts of [resin fine particle dispersion 1], 37 parts of 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate were mixed and stirred. A liquid was obtained. This is designated as [Aqueous Phase 1].

Production Example 3
(Manufacture of unmodified polyester)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introducing tube, 770 parts of bisphenol A ethylene oxide 2-mole adduct and 220 parts of terephthalic acid were subjected to polycondensation at 210 ° C. for 10 hours under normal pressure, and then reduced in pressure from 10 to 15 mmHg. And then cooled to 160 ° C., 18 parts of phthalic anhydride was added thereto and reacted for 2 hours to obtain [Unmodified Polyester a].
[Unmodified Polyester a] had a Tg of 42 ° C., a weight average molecular weight (Mw) of 28000, a peak top of 3500, and an acid value of 15.3.

Production Example 4
(Prepolymer production)
640 parts of bisphenol A ethylene oxide 2-mole adduct, 274 parts of isophthalic acid, 20 parts of trimellitic anhydride, and 2 parts of dibutyltin oxide are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe at normal pressure. The reaction was carried out at 230 ° C. for 8 hours, and further reacted for 5 hours while dehydrating at a reduced pressure of 10 to 15 mmHg, then cooled to 160 ° C., 32 parts of phthalic anhydride was added thereto and reacted for 2 hours. Next, the mixture was cooled to 80 ° C. and reacted with 155 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain [isocyanate group-containing prepolymer 1].

Production Example 5
(Production of ketimine compounds)
In a reaction vessel equipped with a stir bar and a thermometer, 30 parts of isophoronediamine and 70 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain [ketimine compound 1].

Production Example 6
(Synthesis of MB)
1200 parts of water, 540 parts of carbon black (manufactured by Printex 35 Dexa) [DBP oil absorption = 42 ml / 100 mg, pH = 9.5] and 1200 parts of polyester resin are added and mixed with a pressure kneader. After kneading at 150 ° C. for 30 minutes, the mixture was cooled and rolled, and pulverized with a pulverizer to obtain [Masterbatch 1].

Production Example 7
(Create oil phase)
In a container equipped with a stirrer and a thermometer, 378 parts of [unmodified polyester a], 55 parts of carnauba wax, and 947 parts of ethyl acetate were charged, heated to 80 ° C. with stirring, and maintained at 80 ° C. for 5 hours. Thereafter, it was cooled to 30 ° C. in 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Raw material solution 1] 1324 parts are transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads are 80% by volume. Carbon black and WAX were dispersed under conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [unmodified polyester a] was added, and three passes were performed with the bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1].

Example 1
(Manufacture of toner)
Emulsification ⇒ Solvent removal [Pigment / WAX dispersion 1] 749 parts, [Isocyanate group-containing prepolymer 1] 115 parts, [Ketimine compound 1] 2.9 parts in a container, TK homomixer (manufactured by Tokushu Kika) After mixing at 5,000 rpm for 1 minute, 1000 parts of [Aqueous phase 1] was added to the container, and mixed for 5 minutes at a rotation speed of 5000 rpm with Filmix (manufactured by Tokushu Kika) to obtain [Emulsion slurry 1]. . At this time, the liquid temperature was kept at 20 ° C. ± 2 ° C. and aged for 3 hours after emulsification. The particle size immediately after emulsification at this time is 2.5 μm, and the dried product of the emulsion is kneaded with a lab plast mill, and the 1/2 outflow temperature is measured with a flow tester to check the progress of the urea reaction.
The target reaction and the emulsified particle size were examined, and the reaction was completed when it reached 4-5 μm.
[Emulsion slurry 1] was put into a container equipped with a stirrer and a thermometer, and the solvent was removed at 30 ° C. for 8 hours to obtain [Dispersion slurry 1].

Wash ⇒ Dry [Dispersion Slurry 1] After filtering 100 parts under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(4): Add 300 parts of ion-exchanged water to the filter cake of (3), mix with a TK homomixer (10 minutes at 12,000 rpm) and then filter twice to obtain [Filter cake 1]. It was.
[Filtration cake 1] was dried at 45 ° C. for 48 hours in a circulating drier, and sieved with an opening of 75 μm mesh to obtain [Toner 1].

  Next, 100 parts of base particles and 0.25 part of charge control agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) are charged into a Q-type mixer (Mitsui Mining Co., Ltd.) with respect to the base particles of the obtained colored powder. The peripheral speed of the turbine blades was set to 50 m / sec, the operation was performed for 2 minutes, and the pause for 1 minute was performed for 5 cycles, and the total processing time was 10 minutes.

Further, 0.5 part of hydrophobic silica (H2000, manufactured by Clariant Japan) was added, and the peripheral speed was 15 m / sec, mixing for 30 seconds and resting for 1 minute were performed for 5 cycles, and black toner (1) was obtained.
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. Further, the obtained toner had a circularity of 0.93 and a spindle shape. An SEM photograph of the toner is shown in FIG.

Production Example 8
(Synthesis of resin fine particle emulsion)
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 80 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate, 12 parts of butyl thioglycolate and 1 part of ammonium persulfate were added and stirred for 15 minutes at 400 rpm, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion 2] was obtained. The volume average particle diameter of the [resin fine particle dispersion 2] measured by LA-920 was 120 nm. A portion of [resin fine particle dispersion 2] was dried to isolate the resin component. The resin content had a Tg of 52 ° C. and a weight average molecular weight of 300,000.

Example 2
[Toner 2] was obtained in the same manner as in Example 1 except that [Resin fine particle dispersion 2] was used instead of [Resin fine particle dispersion 1] in Example 1, and black toner (2) was obtained.
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.92 and a spindle shape.

Production Example 9
(Synthesis of resin fine particle emulsion)
In a reaction vessel equipped with a stir bar and a thermometer, 760 parts of water, 14 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, Sanyo Chemical Industries), 103 parts of styrene, 83 parts of methacrylic acid, When 90 parts of butyl acrylate, 12 parts of butyl thioglycolate, and 1 part of ammonium persulfate were charged and stirred for 15 minutes at 400 rpm, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion 3] was obtained. The volume average particle diameter of [resin fine particle dispersion 3] measured with LA-920 was 60 nm. A portion of [resin fine particle dispersion 3] was dried to isolate the resin component. The Tg of the resin was 63 ° C., and the weight average molecular weight was 150,000.

Example 3
[Toner 3] was obtained in the same manner as in Example 1, except that [Resin fine particle dispersion 3] was used instead of [Resin fine particle dispersion 1] in Example 1, and black toner (3) was obtained.
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.91 and a spindle shape.

Production Example 10
(Synthesis of resin fine particle emulsion)
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 78 parts of styrene, 83 parts of methacrylic acid, When 105 parts of butyl acrylate, 2 parts of butyl thioglycolate and 1 part of ammonium persulfate were added and stirred for 15 minutes at 400 rpm, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion 4] was obtained. The average particle diameter of [resin fine particle dispersion 4] measured by LA-920 was 30 μm. A portion of [resin fine particle dispersion 4] was dried to isolate the resin component. The resin content Tg was 56 ° C. and the weight average molecular weight was 500,000.

Example 4
[Toner 4] was obtained in the same manner as in Example 1, except that [Resin fine particle dispersion 4] was used instead of [Resin fine particle dispersion 1] in Example 1, and black toner (4) was obtained.
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.95 and a spindle shape.

Production Example 11
(Manufacture of unmodified polyester)
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 196 parts of bisphenol A propylene oxide 2 mole adduct, 553 parts of bisphenol A ethylene oxide 2 mole adduct, 210 parts terephthalic acid, 79 parts adipic acid and dibutyl Add 2 parts of tin oxide, react at 230 ° C. for 8 hours at normal pressure, and further react for 5 hours at a reduced pressure of 10 to 15 mmHg, then add 26 parts of trimellitic anhydride to the reaction vessel, and add 2 parts at 180 ° C. with an upper pressure of 2 By reacting for a time, [unmodified polyester b] was obtained. [Unmodified Polyester b] had a number average molecular weight of 6200, a weight average molecular weight of 36000, Tg of 33 ° C., and an acid value of 15.

Example 5
[Toner 5] was obtained in the same manner as in Example 4 except that [Non-modified polyester b] was used instead of [Non-modified polyester a] in Example 4, and Black toner (5) was obtained.
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.93 and a spindle shape.

Comparative Example 1
After warming the 0.1M-Na ₃ PO ₄ aqueous solution 451g to put to 60 ° C. in deionized water 709 g, and stirred at 12,000rpm using a TK homomixer. To this, 68 g of 1.0 M CaCl ₂ aqueous solution was gradually added to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ . 170 g of styrene, 30 g of 2-ethylhexyl acrylate, 3.4 g of ethylene glycol diacrylate, 10 g of legal 400R, 60 g of paraffin wax (sp. 70 ° C.), 5 g of a metal compound of di-tert-butylsalicylate, styrene-methacrylic acid copolymer ( 10 g of Mw 50,000, acid value 20 mgKOH / g) was put into a TK homomixer, heated to 60 ° C., and uniformly dissolved and dispersed at 12,000 rpm. In this, 10 g of a polymerization initiator, 2,2′-azobis (2,4-dimethylvaleronitrile), was dissolved to prepare a polymerizable monomer system. The polymerizable monomer system was put into the aqueous medium and stirred at 10,000 rpm for 20 minutes in a TK homomixer at 60 ° C. in an N ₂ atmosphere to granulate the polymerizable monomer system. Then, after making it react with a paddle stirring blade for 3 hours at 60 degreeC, liquid temperature was made 80 degreeC and it was made to react for 10 hours.
After completion of the polymerization reaction, the mixture was cooled, and hydrochloric acid was added to dissolve calcium phosphate, followed by filtration, washing with water and drying to obtain [Toner Comparison 1]. [Toner Comparison 1] was mixed with additives in the same manner as in Example 1 to obtain Toner Comparison (1).
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.97 and a spherical shape.

Production Example 12
(Preparation of aqueous dispersion of wax particles)
1000 ml of distilled water degassed into a 4-head Kolben with a stirring device, temperature sensor, nitrogen inlet tube and cooling tube, 28.5 g of New Coal 565C (manufactured by Nippon Emulsifier Co., Ltd.), 1 (manufactured by Noda Wax) 185.5 g was added, and the temperature was raised while stirring under a nitrogen stream. When the internal temperature was 85 ° C., a 5N sodium hydroxide aqueous solution was added and the temperature was raised to 75 ° C. as it was, followed by continuing heating and stirring as it was for 1 hour and cooling to room temperature to obtain [Wax Particle Aqueous Dispersion 1].

Production Example 13
(Preparation of aqueous colorant dispersion)
After adding 100 g of carbon black (trade name: Mogal L, manufactured by Cabot Corporation) and 25 g of sodium dodecyl sulfate to 540 ml of distilled water and sufficiently stirring, a pressure type disperser (MINI-LAB: manufactured by Lani Corporation) was used. Dispersion was performed to obtain [Colorant Dispersion Liquid I].

Production Example 14
(Synthesis of aqueous binder fine particle dispersion)
A 1 L 4-head Kolben equipped with a stirrer, cooling tube, temperature sensor and nitrogen inlet tube is 480 ml of distilled water, 0.6 g of sodium dodecyl sulfate, 106.4 g of styrene, 43.2 g of n-butyl acrylate, 10.4 g of methacrylic acid. The mixture was heated to 70 ° C. under a nitrogen stream while stirring. Here, an initiator aqueous solution in which 2.1 g of potassium persulfate was dissolved in 120 ml of distilled water was added, and the mixture was stirred at 70 ° C. for 3 hours under a nitrogen stream to complete the polymerization, and then cooled to room temperature. A fine particle dispersion 1] was obtained.

  A 5 L 4-head Kolben equipped with a stirrer, a condenser, a temperature sensor, and a nitrogen inlet tube was used. The mixture was heated to 70 ° C. under a nitrogen stream while adding 4 g and stirring. Here, an initiator aqueous solution prepared by dissolving 11.2 g of potassium persulfate in 600 ml of distilled water was added, and the mixture was stirred at 70 ° C. for 3 hours in a nitrogen stream to complete the polymerization, and then cooled to room temperature. A fine particle dispersion 2] was obtained.

Comparative Example 2
In a 1 L separable flask equipped with a stirrer, a condenser, and a temperature sensor, 47.6 g of [High molecular weight binder fine particle dispersion 1], 190.5 g of [Low molecular weight binder fine particle dispersion 2], [Wax particle aqueous dispersion 1] ], 26.7 g of [Colorant Dispersion Liquid I] and 252.5 ml of distilled water were added, mixed and stirred, and adjusted to pH = 9.5 using 5N aqueous sodium hydroxide solution. Further, with stirring, a surfactant in which 50 g of sodium chloride was dissolved in 600 ml of distilled water, 77 ml of isopropanol, and Fluorard FC-170C (manufactured by Sumitomo 3M: Fluoro-based nonionic surfactant) 10 mg in 10 ml of distilled water. Aqueous solutions were sequentially added, the internal temperature was raised to 85 ° C., the reaction was performed for 6 hours, and then cooled to room temperature. The reaction solution was adjusted to pH = 13 with 5N-aqueous sodium hydroxide solution, filtered, resuspended in distilled water, repeatedly filtered and resuspended, washed, dried, and [ Toner comparison 2] was obtained. [Toner Comparison 2] was mixed with an additive in the same manner as in Example 1 to obtain Toner Comparison (2).
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.96 and a spindle shape.

Production Example 15
(Synthesis of resin fine particle emulsion)
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30: manufactured by Sanyo Chemical Industries), 138 parts of styrene, 138 parts of methacrylic acid, When 1 part of ammonium persulfate was charged and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous dispersion of a vinyl resin (a copolymer of styrene-methacrylic acid-methacrylic acid etherene oxide adduct sulfate sodium salt) [ Resin fine particle dispersion 6] was obtained. The volume average particle diameter of [resin fine particle dispersion 6] measured by LA-920 was 140 nm. A portion of [resin fine particle dispersion 6] was dried to isolate the resin component. The Tg of the resin was 156 ° C., and the weight average molecular weight was 400,000.

Comparative Example 3
[Toner Comparison 3] was obtained in the same manner as in Example 1 except that [Resin Fine Particle Dispersion 1] was used instead of [Resin Fine Particle Dispersion 1] in Example 1. [Toner Comparison 3] was mixed with additives in the same manner as in Example 1 to obtain Toner Comparison (3).
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.92 and a spindle shape.

Production Example 16
(Manufacture of resin fine particles)
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 63 parts of styrene, 83 parts of methacrylic acid, When 130 parts of butyl acrylate, 12 parts of butyl thioglycolate and 1 part of ammonium persulfate were added and stirred for 15 minutes at 400 rpm, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion 7] was obtained. The volume average particle diameter of the [resin fine particle dispersion 7] measured by LA-920 was 130 nm. A portion of [resin fine particle dispersion 7] was dried to isolate the resin component. The resin component had a Tg of 45 ° C. and a weight average molecular weight of 50,000.

Comparative Example 4
[Toner Comparison 4] was obtained in the same manner as in Example 1 except that [Resin Fine Particle Dispersion 7] was used instead of [Resin Fine Particle Dispersion 1] in Example 1.
To 100 parts of the obtained toner, 0.7 part of hydrophobic silica and 0.3 part of hydrophobic titanium oxide were mixed with a Henschel mixer to obtain toner comparison (4).
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.94 and a spindle shape.

Production Example 17
(Manufacture of resin fine particles)
In a reaction vessel equipped with a stirrer and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion 8] was obtained. The volume average particle diameter of the [resin fine particle dispersion 8] measured by LA-920 was 80 nm. A portion of [resin fine particle dispersion 8] was dried to isolate the resin component. The resin content had a Tg of 59 ° C. and a weight average molecular weight of 150,000.

Production Example 18
(Prepolymer production)
724 parts of bisphenol A ethylene oxide 2-mole adduct, 276 parts of isophthalic acid and 2 parts of dibutyltin oxide were placed in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and reacted at 230 ° C. for 8 hours at normal pressure. The mixture was further reacted for 5 hours while dehydrating at a reduced pressure of 10 to 15 mmHg, then cooled to 160 ° C., 32 parts of phthalic anhydride was added thereto, and the mixture was reacted for 2 hours. Next, the mixture was cooled to 80 ° C. and reacted with 188 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain [Isocyanate group-containing prepolymer comparison 3].

Production Example 19
(Manufacture of unmodified polyester)
In the same manner as above, 724 parts of bisphenol A ethylene oxide 2-mole adduct, 138 parts of terephthalic acid and 138 parts of isophthalic acid were polycondensed at 230 ° C. for 6 hours under normal pressure, and then reacted for 5 hours while dehydrating at a reduced pressure of 10 to 15 mmHg. [Non-modified polyester comparison 3] was obtained.

Comparative Example 5
15.4 parts of [Isocyanate group-containing prepolymer comparison 3], 64 parts of [unmodified polyester comparison 3] and 78.6 parts of ethyl acetate were placed in a beaker, and dissolved by stirring. Next, 20 parts of pentaerythritol tetrabehenate and 10 parts of carbon (REAMAL400R: manufactured by Cabot) were added and stirred at 12,000 rpm with a TK homomixer at 60 ° C. to uniformly dissolve and disperse. Finally, 2.7 parts of [ketimine compound 1] was added and dissolved. This is referred to as toner material solution comparison (1). In a beaker, 706 parts of ion-exchanged water, 294 parts of hydroxyapatite 10% suspension (Superite 10 manufactured by Nippon Chemical Industry Co., Ltd.) and 0.2 part of sodium dodecylbenzenesulfonate were uniformly dissolved. Next, the temperature was raised to 60 ° C., and while stirring at 12000 rpm with a TK homomixer, the toner material solution comparison (1) was added and stirred for 10 minutes. Next, this mixed solution was transferred to a Kolben equipped with a stirrer and a thermometer, heated to 55 ° C., and the solvent was removed under conditions of 25 to 50 mmHg while allowing urea reaction, filtered, washed and dried. Wind classification. Subsequently, 100 parts of toner particles were mixed with 0.5 part of colloidal silica (Aerosil R972: manufactured by Nippon Aerosil) using a sample mill to obtain [Toner Comparison 5].
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.95 and a spindle shape.

Production Example 20
(Toner binder synthesis)
Bisphenol A ethylene oxide 2-mole adduct 325 parts and terephthalic acid 155 parts were polycondensed using 2 parts of dibutyltin oxide as a catalyst to obtain [Comparative Toner Binder 4]. [Comparative Toner Binder 4] had a Tg of 61 ° C.

Comparative Example 6
In a beaker, 100 parts of the above [Comparative Toner Binder 4], 200 parts of an ethyl acetate solution, 8 parts of carbon black (# 44 manufactured by Mitsubishi Chemical) and 5 parts of the rice wax used in Example 1 were placed at 50 ° C. at TK. The mixture was stirred at 12,000 rpm with a type homomixer and uniformly dissolved and dispersed. Subsequently, the toner was converted into a toner in the same manner as in Example 1 to obtain [Toner Comparison 6] having a weight average particle diameter of 4.5 μm.
The physical property values of the obtained toner are shown in Table 1, and the evaluation results are shown in Table 2. The obtained toner had a circularity of 0.97 and a spherical shape.

Each test method Kneading test method using lab plast mill (i) lab plast mill Type 30C150 manufactured by Toyo Seiki Seisakusho
(Ii) Small pulverizer (Oaster mixer)
(Iii) Test sieve (iv) Work procedure The toner is melt-kneaded using a lab plast mill, and the kneaded product is pulverized with an aster mixer, and a 180 μm mesh ON product is used as a sample.
Laboplast mill kneading conditions:
Mixer: R60
Temperature: 130 ° C
Time: 15 minutes
Sample amount: 45g
Mixer rotation speed: 50 RPM

2. For example, there is an elevated flow tester CFT500D manufactured by Shimadzu Corporation. The flow curve of this flow tester becomes the data shown in FIGS. 3A and 3B, from which each temperature can be read. In FIG. 3, Ts is the softening temperature, Tfb is the outflow start temperature, and the melting temperature in the 1/2 method is the 1/2 outflow temperature by the flow tester.
"Measurement condition"
Load: 5 kg / cm ² , temperature rising rate: 3.0 ° C./min,
Die diameter: 1.00 mm, die length: 10.0 mm

3. Method for measuring THF-insoluble matter About 1.0 g (A) of resin or toner is weighed.
To this, about 50 g of THF (tetrahydrofuran) is added and allowed to stand at 20 ° C. for 24 hours.
This is first separated by centrifugation and filtered using a quantitative filter paper.
The solvent content of this filtrate is vacuum-dried, and the residual amount (B) is measured only for the resin content.
This residual amount is the amount dissolved in THF.
The THF insoluble content (%) is obtained from the following formula.
THF insoluble matter (%) = (A−B) / A

Next, the following evaluation was performed using the obtained toner. The image evaluation was performed on 100,000 sheets using an image NEO450 manufactured by Ricoh Co., Ltd., using a two-component developer prepared as follows.
Preparation Method of Two-Component Developer 50 parts of toner and 950 parts of a silicone resin film carrier (silicon resin: KR250 manufactured by Shin-Etsu Chemical Co., Ltd., 70 μm core material carrier) were mixed and sufficiently shaken to obtain a developer.

Minimum fixing temperature Ricoh Co., Ltd. Co., Ltd. using a Teflon (registered trademark) roller as a fixing roller MF-200 with a modified MF-200 fixing unit, Ricoh type 6200 paper was set on this and a copy test was performed. I did it. The fixing roll temperature at which the residual ratio of the image density after rubbing the fixed image with a pad becomes 70% or more was determined as the minimum fixing temperature.

Hot offset generation temperature (HOT)
Fixing was evaluated in the same manner as the above-described minimum fixing temperature, and the presence or absence of hot offset on the fixed image was visually evaluated. The fixing roll temperature at which hot offset occurred was also used as the hot offset generation temperature.

Toner melting test method Melting out is a mechanism in which the toner adhering to the fixing roller during fixing moves to the pressure roller and the toner is collected by the cleaning roller. A phenomenon that begins to melt again due to roller heat and adheres to and contaminates an image via a pressure roller.
As a test method, a melting out endurance run is carried out, and toner is attached to the cleaning roller to check a difference in melting out. An image was output under the following conditions, and the number of melted out sheets until the image became dirty was confirmed.
<Conditions>
Copier: RICOH made by RICOH Neo 451
Fixing unit for evaluation: IMAGO Neo 451 manufactured by RICOH
(Pressurized diameter: φ30) Fixing device Run mode: 1to15 interval 30S 6% chart 15K / day

Heat-resistant storage stability Measuring instrument: Penetration tester (Nikka Engineering)
Tapping machine
30mL screw vial Storage: Constant temperature Method: (1) Collect 10.8g of toner in a screw vial (2) Apply the toner of (1) to the tapping machine 150 times / 1 minute 35 seconds
(3) Quietly store in a constant temperature layer at a predetermined temperature of 50 ° C. for 24 hours. (4) Rest for 2 hours after 24 hours. (5) Drop the needle with a penetration tester and test the penetration.
○: Needle penetration degree 15mm or more
Δ: Needle penetration degree 10-14mm
X: Needle penetration degree 9 mm or less

Fluidity An index of toner fluidity is measured by measuring the bulk density. The bulk density was measured using a powder tester made by Hosokawa Micron. The toner with better fluidity has a higher bulk density.
1. Configuration of measuring instrument (1) Measuring cylinder (50ml (± 0.25ml TC20 ℃))
(2) Stopwatch (3) Electronic balance (measurement accuracy: within 0.1 g)
2. Measurement procedure (1) The sample amount of the predetermined value 1 is measured with an electronic balance.
(2) Weigh the graduated cylinder to the last digit.
(3) At the same time that the sample has been put in, start measuring the stopwatch and leave it for 10 to 11 minutes. During this time, pay attention to vibration and shock.
(4) The powder volume is read to 0.5 ml with a graduated cylinder scale.
(5) Measure the weight of the sample + graduated cylinder to the last digit.
(6) The calculation method is as follows.
Evaluation criteria ○: 0.40 g / cm ³ or more Δ: 0.35 to 0.39 g / cm ³
X: 0.30 g / cm ³ or less

Image Fixing Evaluation Method Using a device in which the fixing unit of Ricoh Co., Ltd. imagio NEO450 as a fixing roller was modified as follows, type 6200 paper made by Ricoh was set on this and a copying test was performed. For the fixing device, a metal cylinder of a fixing roller having a Fe material thickness of 0.34 mm was used, and the surface pressure was set to 1.0 × 10 ⁵ Pa.

Image Density Test Method Use a Macbeth reflection densitometer to correct for the standard version and obtain the relative density.
The measurement part measured a circle with a solid part of 5 mm to 10 mm.
Image density criteria:
○: 1.5 or more Δ: 1.4 to less than 1.5 ×: less than 1.4

Resolving power test method A pattern consisting of five fine lines having the same line width and spacing, and 2.8, 3.2, 3.6, 4.0, 4.5, 5.0, 5.6, 1 mm. 6.3, 7.1, and 8.0 copies of the original image, and the obtained copy image is observed with a magnifying glass at 5x, and the number of images clearly separated between thin lines (lines / mm) as resolution.
Resolution criteria:
○: 6.3 pieces / mm or more Δ: 5.0 to 5.6 pieces / mm
×: 4.5 / piece

Examples 1 to 5 achieve low-temperature fixing, and no fouling due to melting from the fixing cleaning roller is observed.
Comparative Example 1 has a large particle size and poor low temperature fixability. Since there are many particles of 3 μm or less, the fluidity is lowered.
In Comparative Example 2, since no insoluble matter is contained in the toner, a decrease in hot offset property and contamination due to dissolution from the fixing cleaning roller occur.
In Comparative Example 3, since the Tg of the resin fine particles is high, the lower limit of fixing is high.
In Comparative Example 4, since the Tg of the resin fine particles is low, the heat resistant storage stability is lowered.
In Comparative Example 5, the 1/2 outflow temperature after the toner kneading is low, so that contamination due to melting from the fixing cleaning roller occurs.
In Comparative Example 6, since the Tg of the toner is high, the low-temperature fixability is lowered. Moreover, the hot offset property is also lowered.

FIG. 6 is an explanatory diagram of melted toner in a heat fixing device. FIG. 3 is a configuration diagram of toner particles of the present invention. It is a flow curve which calculates | requires the 1/2 outflow temperature by a flow tester. 1 is a schematic configuration diagram of an example of an image forming apparatus of the present invention. 2 is an example of a thermal fixing device used in the image forming apparatus of the present invention. FIG. 2 is a diagram illustrating a schematic configuration of a process cartridge having a dry toner according to the present invention. FIG. 2 is a diagram showing a schematic configuration of a process cartridge having a two-component developer according to the present invention. 2 is an SEM photograph of the toner obtained in Example 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 2 Developing means 3-3 Residual developer 3a Toner 3b Magnetic carrier 4 Developing sleeve 5 Magnet roller 6 Doctor blade 7 Developer storage case 7a Predoctor 8 Toner hopper 8a Toner replenishing port 9 Agitator 10 Photoreceptor 11 Charging device DESCRIPTION OF SYMBOLS 12 Developing device 13 Transfer device 14 Cleaning device 15, 16 Roller 17 Transfer belt 20 Toner replenishment device 21 Registration roller 22 Heat fixing device 30 Heating member 32 Pressure member 47 Laser writing device 50 Charging roller (charging means)
53 Light source 58 Cleaning means 74 Cleaning member 80 Magnetic field forming means 84 Toner removal member 100 Copier apparatus main body 200 Image reading apparatus 300 Sheet bank 400 Automatic document feeder D Development area S Sheet S 'Developer container

Claims (14)

  At least fine droplet particles containing an organic solvent, a binder resin, a colorant, and a wax were obtained by removing the organic solvent contained in a dispersion liquid dispersed in an aqueous medium containing resin fine particles. The toner has a glass transition point (Tg) of the toner of 30 to 46 ° C., and the glass transition point (Tg) of the resin fine particles coated on the toner surface is 50 to 70 ° C. A dry toner having a 1/2 outflow temperature of 95 to 120 ° C when masticated with a lab plast mill, and a 1/2 outflow temperature before mastication of 120 to 145 ° C.   2. The dry toner according to claim 1, wherein the content of insoluble tetrahydrofuran (THF) in the toner is 5 to 25% by weight.   The weight average particle diameter of the toner measured by the Coulter method is 3.0 to 6.0 μm, and the particle size distribution is 1.00 ≦ Dv / Dn ≦ 1.20 (Dv: weight average particle diameter, Dn: number average) The dry toner according to claim 1, wherein the dry toner is a particle size.   The dry toner according to any one of claims 1 to 3, wherein, in a particle size distribution measured by a flow type particle image measuring device, the number-based fine powder content with a particle size of 2 µm or less is 15% or less. .   5. The dry toner according to claim 1, wherein the content of coarse powder having a particle size of 8 μm or more is 2% by weight or less in a particle size distribution measured by a Coulter method.   The dry toner according to any one of claims 1 to 5, wherein in the particle size distribution measured by the Coulter method, the content of fine powder having a particle size of 3 µm or less is 2 wt% or less.   The dry toner according to claim 1, wherein the dry toner has a spindle shape with an average circularity of 0.900 to 0.960 as measured by a flow type particle image measuring apparatus.   The dry toner according to claim 1, wherein the resin fine particles have an average particle size of 10 to 200 nm.   At least fine droplet particles containing an organic solvent, a binder resin, a colorant, and a wax were obtained by removing the organic solvent contained in the dispersion liquid dispersed in the aqueous medium containing the resin fine particles. The toner dissolves or disperses at least a modified polyester resin capable of reacting with an active hydrogen group-containing compound, a colorant, and a wax in an organic solvent, and the dissolved or dispersed solution in an aqueous medium in the presence of resin fine particles. A toner obtained by dispersing and polyaddition reaction with a compound having active hydrogen and removing the solvent of the resulting dispersion, wherein the toner contains a modified polyester resin. The dry toner according to any one of 1 to 8.   The modified polyester-based resin contained in the toner contains a tetrahydrofuran-soluble component, and the tetrahydrofuran-soluble component has a main peak in a molecular weight range of 2500 to 10,000 and a molecular weight having a number average molecular weight in the range of 1500 to 15000. The dry toner according to claim 9, which has a distribution.   The dry polyester according to claim 9 or 10, wherein the modified polyester resin capable of reacting with the compound having an active hydrogen group contains an isocyanate group, and the polyaddition reaction is an extension reaction and / or a crosslinking reaction. toner.   A two-component developer using the dry toner according to any one of claims 1 to 11 and a carrier. In an image forming apparatus having a heat fixing device for fixing a toner image on a recording medium while passing the recording medium between a heating member and a pressure member, the toner adhering to the heating member and / or the pressure member is removed. An image forming apparatus that includes a cleaning member that performs fixing by a fixing device having a surface pressure (roller load / contact area) applied between a heating member and a pressure member of 1.5 × 10 ⁵ Pa or less. An image forming apparatus using the toner or the developer according to any one of .about.12.   In a process cartridge that integrally supports at least one unit selected from a photosensitive member and a charging unit, a developing unit, and a cleaning unit and is detachable from the main body of the image forming apparatus, the developing unit includes toner or developer. A process cartridge that is held and the toner or developer is the dry toner or developer according to claim 1.