JP2003207931A - Non-magnetic toner and fixing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide non-magnetic toner and a fixing method by which the heating part of material to be heated is set to a state where it rises to specified temperature in a short period of time (quick start ability), the fixing property of a color toner image is completely secured, and uniform glossiness (gloss) is obtained at the leading edge and the trailing edge of an image on the material to be heated and further when many sheets are made to pass. <P>SOLUTION: The non-magnetic toner and the fixing method are used for an image forming method using a heating and pressurizing means including a magnetic field generation means, a rotary heating member having at least a heat generation layer generating heat by electromagnetic induction, an elastic layer, and a mold-released layer, and a rotary pressurizing member forming a nip with the rotary heating member, and forming a fixed image on the recording material by thermally heating, pressurizing, and fixing the non-magnetic toner image on the recording material while making the rotary pressurizing member press to the rotary heating member across the recording material. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt heating type heating device, and a non-magnetic toner used in an image forming apparatus such as an electrophotographic device or an electrostatic recording device having the heating device as an image heating device, and a fixing device. Regarding the method.

[0002]

2. Description of the Related Art For the sake of convenience, an image heating device (fixing device), which is provided in an image forming device such as a copying machine or a printer, for heating and fixing a toner image on a recording material will be described as an example.

In an image forming apparatus, a recording material (transfer material sheet, electrofax sheet, electrostatic recording paper, OHP sheet, etc.) is recorded by an appropriate image forming process means such as an electrophotographic process, an electrostatic recording process, a magnetic recording process or the like. A heat roller is used as a fixing device that heats and fixes an unfixed image (toner image) of the target image information formed and carried on a printing paper or format paper by a transfer method or a direct method as a permanently fixed image on the recording material surface. The device of the method was widely used. Recently, belt heating type devices have been put to practical use from the viewpoint of quick start and energy saving. An electromagnetic induction heating type device has also been proposed.

A) Heat roller type fixing device This is basically a pressure contact roller pair of a fixing roller (heating roller) and a pressure roller, and is a mutual pressure contact portion of the roller pair by rotating the roller pair. The recording material on which the unfixed toner image to be image-fixed is carried is introduced and nipped and conveyed in the fixing nip portion, and the unfixed toner image is recorded by the heat of the fixing roller and the pressing force of the fixing nip portion. The material is fixed by heat and pressure on the material surface.

In general, the fixing roller has an aluminum hollow metal roller as a base body (core bar), and a halogen lamp as a heat source is inserted and disposed in the inner space of the fixing roller. The temperature of the halogen lamp is controlled by controlling the energization so that the halogen lamp is maintained at a predetermined fixing temperature.

In particular, as a fixing device of an image forming apparatus for forming a full-color image, which is required to sufficiently heat and melt a maximum of four toner image layers to mix colors, a core metal of a fixing roller has a high heat capacity. Further, a rubber elastic layer for wrapping the toner image around the core metal and melting it uniformly is provided, and the toner image is heated through the rubber elastic layer. There is also a structure in which a heat source is also provided in the pressure roller so that the pressure roller can be heated and temperature controlled.

However, in the heat roller type fixing device, even if the power source of the image forming apparatus is turned on and the halogen lamp which is the heat source of the fixing device is simultaneously energized, the heat capacity of the fixing roller is large and the fixing roller and the like are cooled. A considerable waiting time (wait time) is required from the state of being cut to the time when the temperature can be fixed to a predetermined fixing temperature, and the quick start property is lacking. In addition, it is necessary to energize the halogen lamp to keep the fixing roller in a predetermined temperature control state so that the image forming operation can be executed at any time even when the image forming apparatus is in the standby state (when no image is output). There was a problem such as a large amount.

Further, in a fixing device having a particularly large heat capacity such as the fixing device of the above-mentioned full-color image forming apparatus, there is a delay in temperature adjustment and a temperature rise on the surface of the fixing roller, so that fixing failure may occur. Problems such as uneven gloss and offset occurred.

B) Film heating type fixing device A film heating type fixing device is disclosed, for example, in JP-A-63-31318.
No. 2, JP-A-2-157878, and JP-A-4-
It is proposed in Japanese Patent Laid-Open No. 44075, Japanese Patent Laid-Open No. 4-204980, and the like.

That is, a nip portion is formed by sandwiching a heat-resistant film (fixing film) between a generally ceramic heater as a heating body and a pressure roller as a pressure member, and the nip portion is added to the film. The recording material on which an unfixed toner image to be fixed is formed and carried between the pressure roller and the recording material is nipped and conveyed together with the film, so that the heat of the ceramic heater in the nip portion is transferred through the film to the recording material. In addition, the unfixed toner image is thermally and pressure-fixed on the surface of the recording material by the pressing force of the nip portion.

This film heating type fixing device can constitute an on-demand type device by using a ceramic heater and a member having a low heat capacity as a film, and a ceramic heater as a heat source only when image formation is performed in the image forming device. It is only necessary to energize the printer to generate heat at a predetermined fixing temperature, the waiting time from the power-on of the image forming apparatus to the image forming executable state is short (quick start property), and the power consumption during standby is also significantly increased. There are advantages such as small size (power saving).

However, the full-color image forming apparatus, which requires a large amount of heat, and the fixing device for high-speed models, have a heat quantity problem.

C) Electromagnetic induction heating type fixing device Japanese Utility Model Laid-Open No. 51-109739 discloses an induction heating fixing device in which a magnetic flux induces a current in a fixing roller to generate heat by Joule heat. This makes it possible to directly generate heat in the fixing roller by utilizing the generation of the induced current, and achieves a fixing process with higher efficiency than that of a heat roller type fixing device using a halogen lamp as a heat source.

However, since the energy of the alternating magnetic flux generated by the exciting coil as the magnetic field generating means is used to raise the temperature of the entire fixing roller, there is a large heat dissipation loss, and the density of the fixing energy with respect to the input energy is low and the efficiency is poor. there were.

Therefore, in order to obtain a high density of energy that acts on the fixing, the exciting coil is brought close to the fixing roller, which is a heating element, or the alternating magnetic flux distribution of the exciting coil is concentrated near the fixing nip portion. An efficient fusing device was devised.

On the other hand, regarding toner, JP-A-1-128
No. 071, JP-A-4-353866, JP-A-6-59504 and the like disclose toners focusing on the viscoelasticity of the resin, but it is still necessary to achieve both low-temperature fixing property and high-temperature offset resistance. There is a need for improvement.

In order to improve the high temperature offset resistance at the time of fixing, a material having a relatively high mold release property such as polyethylene wax or polypropylene wax is generally used, but a large amount of such a low softening point substance is used. When it is contained in the composition, the developability is often poor.

Generally, in color toners, the high temperature offset resistance is improved by applying silicone oil or the like to the surface of the heat fixing roller without adding a release agent. However, the output transfer material obtained in this manner causes problems such as an unpleasant feeling to the user due to the adhesion of excess silicone oil or the like on the surface thereof, and difficulty in viewing due to high gloss.

In order to solve these problems, Japanese Patent Laid-Open No. 10-28
No. 2822, etc., a toner containing a low-softening substance inside the toner by a polymerization method and controlling the physical properties of the resin to satisfy the low-temperature fixability, the high-temperature offset resistance, the image glossiness, and the OHP transparency, and heating. A combination of fixing devices is disclosed.

However, this heat fixing device is of the heat roller type, and has the advantage that it has a long life and that pressure is applied during fixing, but on the other hand it has a long wait time and consumes less power as described above. There was a big problem.

On the other hand, a combination of a fixing device of an electromagnetic induction heating fixing system or a film heating fixing system and a toner containing a low softening point substance, which solves the problems of wait time and power consumption, is disclosed in JP-A-9-204110 and JP-A-10-104110. -488
No. 68 publication and the like.

In these cases, the physical properties of the resin and low-softening substance inside the toner are specified, but because of the fact that a fixing device of the film heating type or electromagnetic induction heating type cannot apply a large pressure at the time of fixing, etc. However, it has been found to be insufficient unless the substance on the outermost surface of the toner and its dispersion state are controlled.

At present, there is no combination of a toner and a heat fixing device that solves various problems.

[0024]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a non-magnetic toner and a heat fixing method which solve the above-mentioned problems of the prior art.

The object of the present invention is to make it possible to raise the heating portion of the material to be heated to a predetermined temperature in a short time (quick start property), to sufficiently secure the fixability of the color toner image, and to improve the image on the material to be heated. It is an object of the present invention to provide a non-magnetic toner and a fixing method capable of achieving a uniform glossiness (gloss) even at the front end and the rear end of a sheet, and even when a large number of sheets are passed.

An object of the present invention is to provide a non-magnetic toner and a fixing method capable of obtaining an image with excellent transparency of an overhead projector film (OHP) image by sufficiently mixing multicolor toners with good color reproducibility. To provide.

[0027]

According to the present invention, there is provided (i) a magnetic field generating means, (ii) a rotary heating member having at least a heat generating layer which generates heat by electromagnetic induction, an elastic layer and a release layer, and (iii) A heating / pressurizing unit having at least the rotary heating member and a rotary pressing member forming a nip is used, and the rotary heating member is pressed through the recording material while pressing the rotary pressing member. Is a non-magnetic toner used in an image forming method of fixing a non-magnetic toner image under heat and pressure to form a fixed image on a recording material. The non-magnetic toner includes the following (a) to (d) (a) 5 parts of low softening point substance to 100 parts by weight of resin
To 40 parts by mass, at least two or more kinds of (b) external additive fine powder are added, and the external additive fine powder has a number average major axis of primary particles of 1 to 40 mm. Is at least one kind, and at least one kind of inorganic fine powder (B) having a number average major axis of 40 to 500 nm generated by combining a plurality of primary particles is added.
(C) The average circularity of the toner particles measured by a flow type particle image analyzer is 0.950 to 0.995,
(D) In the particle size distribution based on the number of toner particles measured by a flow type particle image analyzer, the equivalent circle diameter is 0.6 μm.
5 to 50% by number of particles of m or more and less than 2.0 μm,
The present invention relates to a non-magnetic toner satisfying the following conditions.

The present invention further comprises (i) magnetic field generating means,
(Ii) a rotary heating member having at least a heating layer that generates heat by electromagnetic induction, an elastic layer, and a release layer; and (ii)
i) Using a heating and pressurizing means having at least the rotary heating member and a rotary pressing member forming a nip, the rotary heating member is pressed against the rotary pressing member via a recording material, and the recording is performed. In a fixing method of fixing a non-magnetic toner image on a material by heat and pressure to form a fixed image on a recording material, as the non-magnetic toner, the following (a) to (b) (a) with respect to 100 parts by mass of a binder resin: , Low softening point substance 5
To 40 parts by mass, at least two or more kinds of (b) external additive fine powder are added, and the external additive fine powder has a number average major axis of primary particles of 1 to 40 mm. Is at least one or more, and at least one or more kinds of inorganic fine powder (B) having a number average major axis of 40 to 300 mm generated by combining a plurality of primary particles are added.
(C) The average circularity of the toner particles measured by a flow type particle image analyzer is 0.950 to 0995,
(D) In the particle size distribution based on the number of toner particles measured by a flow type particle image analyzer, the equivalent circle diameter is 0.6 μm.
5 to 50% by number of particles of m or more and less than 2.0 μm,
The present invention relates to a fixing method characterized by using a non-magnetic toner satisfying the above conditions.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION The non-magnetic toner used in the present invention contains at least two kinds of external additive fine powder,
The external additive fine powder has a number average major axis of primary particles of 1 to 40.
nm inorganic fine powder (A) is at least one or more, and at least one or more inorganic fine powder (B) having a number average major axis of 40 to 500 nm generated by combining a plurality of primary particles is added. It is possible to suppress low-temperature fixability, high-temperature offset resistance, and other fixing defects.

Here, the numerical value of the inorganic fine powder (A) was measured by a scanning electron microscope FE-SEM (S-manufactured by Hitachi Ltd.).
4700), a photograph of the surface of the toner particles magnified 100,000 times is taken, and the enlarged photograph is used to measure the major axis of 1 to 40 n.
m particles are measured. The measurement of the major axis of the primary particles is appropriately performed in the range of 100,000 times to 500,000 times.

The average major axis of the primary particles of the inorganic fine powder (A) is measured over 10 fields of view in an enlarged photograph, and the average is taken as the average major axis. In addition, among the parallel lines drawn so as to contact the contour of the primary particles of the inorganic fine powder (A), the one having the maximum distance between the parallel lines is defined as the major axis.

The numerical value of the inorganic fine powder (B) is measured by
Scanning electron microscope FE-SEM (Hitachi S-47
00), a photograph of the surface of the toner particles magnified 50,000 times is taken, and the magnified photograph is used to measure particles having a major axis of 20 nm or more.

The average major axis of the composite particles of the inorganic fine powder (B) is measured in 10 fields of view in an enlarged photograph, and the average is taken as the average major axis. Among the parallel lines drawn so as to contact the contour of the composite particles of the inorganic fine powder (B), the one having the maximum distance between the parallel lines is defined as the major axis.

The distinction between the inorganic fine powder (A) and the composite particles of the inorganic fine powder (B) by the magnified photograph of the scanning electron microscope is made by the scanning electron microscope when the particle shapes of the inorganic fine powder are clearly different. If there is a difference in the shape of the particles in the enlarged photograph, or if there is a difference in the composition of the inorganic fine powder, X
It is possible to use a method in which the determination is made by separately detecting the composite particles of the inorganic fine powder (A) and the inorganic fine powder (B) by detecting only the specific element designated by the line microanalyzer.

In recent years, as the image quality and transfer of electrophotography have been improved, the particle size and sphericity of toner have been reduced. Examples include polymerized toner utilizing suspension polymerization and spheronized toner by mechanical and thermal treatment.

The inventors of the present invention, when fixing a toner having such a high sphericity, show good fixing characteristics with a heat roller method in which sufficient pressure is applied, whereas a film heating method or an electromagnetic induction heating method is used. It has been found that various fixing defects are caused by a method in which large pressure cannot be applied.

Specifically, when the toner is developed and transferred and is placed on the paper, the toner having a high sphericity is in a very tight state. When this passes through the fixing device, it is considered that a slight amount of remaining water, air, or release agent internally added to the toner is prevented from being released, and an offset phenomenon or a blown-out image is generated. .

The above phenomenon is improved by using two or more kinds of external additive fine powders having different particle sizes as described above.

As the external additive fine powder, at least one kind of inorganic fine powder (A) having a number average major axis of primary particles of 1 to 40 nm is required. This relates to charging characteristics of electrophotographic characteristics. That is, the inorganic fine particles of 1 to 40 nm make the charge on the surface of the toner uniform and make the charge amount distribution of the toner sharp, and improve the fluidity of the toner. Further, it is effective in suppressing electrostatic offset by making the toner charge uniform.

When the number average major axis of the primary particles of the inorganic fine powder (A) is less than 1 nm, the inorganic fine powder (A) is buried in the toner surface, and the toner deteriorates with long-term use.

When the number average major axis of the primary particles of the inorganic fine powder (A) is 40 nm or more, the charge on the surface of the toner is poorly uniformized, and the charge amount distribution of the toner becomes broad, resulting in problems such as toner scattering and fog. It is easy to occur.

Further, when the specific surface area of the inorganic fine powder (A) by nitrogen adsorption by the BET method is 50 to 150 m ² / g, the fixing property in the heat fixing device of the present invention is good.

When the specific surface area of the inorganic fine powder (A) due to nitrogen adsorption by the BET method is less than 50 m ² / g, the cohesiveness of the powder is too high and a uniform charging characteristic cannot be obtained. Prone to

When the specific surface area of the inorganic fine powder (A) due to nitrogen adsorption by the BET method is larger than 150 m ² / g, the amount of water adsorbed on the fine powder is large and fixing failure is likely to occur.

In the present invention, the BET specific surface area of the powder is measured using a specific surface area meter Autosorb 1 manufactured by QUANTACHROME as follows.

About 0.1 g of the measurement sample was weighed in a cell, and the temperature was 40 ° C. and the degree of vacuum was 0.133 Pa (1.0 × 10 5).
^-3 mmHg) for 12 hours or more. Then, nitrogen gas is adsorbed in a state of being cooled by liquid nitrogen, and the value is obtained by the multipoint method.

Further, the addition amount of the inorganic fine powder (A) is 0.1 to 2.5 parts by mass, preferably 0.2 to 1.5 parts by mass, based on 100 parts by mass of the toner particles. The fixing characteristics in the heat fixing device are good.

When the addition amount of the inorganic fine powder (A) is less than 0.1 parts by mass, the toner has poor fluidity, developability and transferability are deteriorated, and other external additives are non-uniformly dispersed. Therefore, the fixability also deteriorates.

When the amount of the inorganic fine powder (A) added exceeds 2.5 parts by mass, the amount of the inorganic fine powder present on the toner surface increases, which hinders fixing.

On the other hand, as the inorganic fine powder, a number average major axis of 40 to 500 is produced by combining a plurality of primary particles.
It is necessary to use at least one kind of the inorganic fine powder (B) having a thickness of nm. That is, the inorganic fine particles having a particle size of 40 to 500 nm act as spacer particles to assist the exudation of the release agent contained in the toner and to obtain good fixability. It is also considered to assist the release of air and moisture in the transfer material during fixing.

The number average major axis of the aggregate formed by combining a plurality of primary particles of the inorganic fine powder (B) is 40 nm.
When it is less than, the effect as a spacer cannot be obtained, and
The inorganic fine powder (A) is buried in the toner surface, and the toner deteriorates with long-term use. When the number average major axis of the aggregate formed by coalescing a plurality of primary particles of the inorganic fine powder (B) is larger than 500 nm, the charge on the toner surface is poor in uniformity, and the toner charge amount distribution becomes broad. Problems such as toner scattering and fogging are likely to occur, and the fusion and binding of the toners are also hindered in fixing.

When the specific surface area of the inorganic fine powder (B) by nitrogen adsorption by the BET method is 20 to 90 m ² / g, the fixing property in the heat fixing device of the present invention is good.

When the specific surface area of the inorganic fine powder (B) due to nitrogen adsorption by the BET method is less than 20 m ² / g, the cohesiveness of the powder is too high and the composite particles become too large to prevent fixing.

When the specific surface area of the inorganic fine powder (B) by nitrogen adsorption by the BET method is larger than 90 m ² / g, the composite particles in the present invention are difficult to form and the effect of the present invention is hard to be obtained.

Further, the addition amount of the inorganic fine powder (B) is 0.1 to 2.5 parts by mass, preferably 0.2 to 1.5 parts by mass, based on 100 parts by mass of the toner particles. The fixing characteristics in the heat fixing device are good.

When the addition amount of the inorganic fine powder (B) is less than 0.1 parts by mass, the developing property and transfer property of the toner are deteriorated, and the effect as a spacer is difficult to be exhibited, and the low softening point substance is exuded. This hinders the fixability.

When the amount of the inorganic fine powder (B) added exceeds 2.5 parts by mass, the amount of the inorganic fine powder present on the toner surface increases, which hinders fixing.

Inorganic fine powder (A) used in the present invention,
As the component (B), a conventionally known one can be used, but it is preferably selected from silica, alumina, titania or a sub oxide thereof in order to improve developability, fluidity and storage stability. Among them, silica is preferable for the inorganic fine powder (B) in that the particle size of the primary particles or the coalescence of the primary particles can be controlled to some extent depending on the starting material or the oxidizing conditions such as the temperature. For example, as the silica, both of so-called dry process silica produced by vapor phase oxidation of silicon halide or alkoxide or dry process silica called fumed silica, and wet silica produced from alkoxide and water glass can be used. However, dry silica having less silanol groups on the surface and inside the fine powder and less production residue is preferable.

The inorganic fine powder (B) is preferably manufactured by the following manufacturing method.

When silica fine powder is used as an example, silica fine powder is produced by vapor-phase oxidation of a silicon halide, and the obtained silica fine powder is subjected to a hydrophobic treatment to produce non-spherical silica fine powder. To do. Especially during gas phase oxidation,
It is preferable to perform firing at a high temperature at which primary particles of silica coalesce.

The inorganic fine powder thus obtained may be adjusted in particle size distribution by classification or the like, if necessary.

In the present invention, the composite particles of the inorganic fine powder (A) and the inorganic fine powder (B) may be treated with silicone oil or the like. The treatment may improve the hydrophobicity of the inorganic fine powder and reduce damage to the charging member, the drum, the transfer member, the fixing member, and the like.
Further, it is assumed that the oil treatment also assists the fixability.

In the present invention, the composite particles of the inorganic fine powder (A) and the inorganic fine powder (B) increase the hydrophobicity, and for the purpose of improving the operability of particle size and shape control, silane coupling treatment or alumina coating. You may perform the surface treatment which forms.

Specific examples of the silane coupling agent include hexamethyldisilazane and those represented by the following formula (1).

Rm Si Yn (1) R: alkoxy group or chlorine atom m: integer of 1 to 3 Y: alkyl group or hydrocarbon group containing vinyl group, glusidoxy group or methacryl group n: integer of 1 to 3 Typical examples of the compound represented by (1) include dimethyldichlorosilane, trimethylchlorosilane,
Allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, isobutyltrimethoxysilane, n-butyltrimethoxysilane, vinyltriacetoxysilane,
Examples thereof include divinylchlorosilane and dimethylvinylchlorosilane.

The silane coupling agent may be treated by a dry method in which fine powder is made into a cloud shape by stirring with a vaporized silane coupling agent, or a fine powder is dispersed in a solvent to form a silane coupling agent. The treatment can be carried out by any wet method in which the dropping reaction is carried out.

As a method for forming the alumina coating,
Add aluminum chloride, aluminum nitrate, aluminum sulfate, etc. in an aqueous solution or solvent and immerse the fine particles,
Drying method, hydrous alumina, hydrous alumina-
It can be carried out by a method of adding silica, hydrous alumina-titania, hydrous alumina-titania-silica, or hydrous alumina-titania-silica-zinc oxide, immersing the fine particles in the aqueous solution, and drying.

In the present invention, it is preferable that the average circularity is 0.950 to 0.995 in the particle size distribution according to the equivalent circle diameter measured by the toner flow type particle image analyzer. Here, the flow-type particle image measuring device is a device for statistically performing image analysis of particle imaging, and the average circularity is calculated by an arithmetic mean of circularity obtained by the following equation using the device.

[0069]

[Equation 1]

In the above equation, the perimeter of the projected particle image is
The length of the contour line obtained by connecting the edge points of the binarized particle image, and the perimeter of the equivalent circle is the length of the outer circumference of the circle having the same area as the binarized particle image. is there.

The equivalent circle diameter is the diameter of a circle having the same area as the area of a measured two-dimensional image of a particle.

As a flow type particle image measuring device, FPIA-
It uses 1000 (made by Toa Medical Electronics Co., Ltd.).

As a measuring method, a surfactant (preferably Contaminone manufactured by Wako Pure Chemical Industries, Ltd.) is added to ion-exchanged water in an amount of 0.1 to 0.1.
A sample dispersion liquid was prepared by adding 0.02 g of the measurement sample to 10 ml of the solution prepared by adding 0.5% by mass (20 ° C.) and uniformly dispersing the measurement sample.

As a dispersing means, an ultrasonic dispersing machine UM-50 manufactured by SMT Co., Ltd. (a vibrator is a titanium alloy tip of 5φ) is used, and the dispersing time is 5 minutes, and the temperature of the dispersing medium is 40 ° C. or more. It was cooled so that it would not become.

The measurement was carried out in the range of 0.60 to 400 μm for 22 seconds.
It is divided into 6 channels and the equivalent circle diameter is 0.
Particles are measured in the range of 60 μm or more and less than 159.21 μm.

When the average circularity is 0.950 to 0.995, even in a low gloss image (that is, the toner is fixed without completely dissolving the toner) which is preferred for business use, the printing surface is uniform. The diffuse reflection can be minimized. In addition, it is possible to improve the transparency of transmitted light of a transparency image and minimize a change in hue angle.

On the other hand, if the average circularity is less than 0.950, the roughness of the surface on which the toner shape remains will cause a decrease in transmittance due to irregular reflection and a change in hue angle. Further, due to the irregular toner, the filling property in the unfixed state before passing through the fixing roller is low, and in the fixing constitution which achieves low glossiness, bubbles remain inside and the OHT permeability is lowered.

In the present invention, as a method for producing the toner having the above-mentioned specific average circularity, for example, a method for producing a toner by mechanically or thermally spheroidizing toner particles produced by a pulverization method is used. , And a method of directly producing a toner by a polymerization method.

Further, in the present invention, in the number-based particle size distribution of toner particles measured by a flow type particle image analyzer, 5 to 50% by number of particles have an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm. If so, the fixing property in the heat fixing device of the present invention is good.

This is similar to the above-mentioned inorganic fine powder (B) composite particles, particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm act as spacer particles, and release air and water during fixing and cause the internal particles of the toner. Good fixability can be obtained by assisting the exudation of the release agent contained therein.

As the particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm in the present invention, organic fine particles synthesized by polymerization are preferable. This is because from the viewpoint of having the effect as spacer particles, it is difficult to inhibit fixing by melting by heating.

When the content of particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm is less than 5% by number, the effect of the spacer particles of the present invention is lowered.

If the content of the particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm is more than 50% by number, the fusion and binding of the toner particles may be hindered or the developability may be deteriorated.

The particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm in the present invention may be particles separately synthesized with toner particles or particles simultaneously synthesized when a toner is manufactured by a polymerization method.

Examples of the low softening point substance used in the toner of the present invention include paraffin wax, polyolefin wax, modified products thereof (for example, oxides and graft-treated products), higher fatty acids and their metal salts, and amides. Examples of waxes include ester waxes, but when used in color toners, high crystallinity results in OH.
Amide wax and ester wax are preferable because they impede the permeability of P.

The low softening point substance is the binder resin 100 of the toner.
5 to 40 parts by weight, preferably 10 to 3 parts by weight
It is preferable to add 0 part by mass.

When the compounding amount of the low softening point substance is less than the lower limit, the offset prevention effect tends to be lowered, and when it is more than the upper limit, the blocking resistance effect is lowered and the offset resistance effect is liable to be adversely affected. Adhesion is liable to occur, and a toner having a wide particle size distribution tends to be produced particularly in the case of the polymerized toner production method.

The low softening point substance used in the present invention has a ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) in the molecular weight distribution measured by GPC (gel permeation chromatography). ) Is preferably 1.0 to 5.0.

This means that the closer the Mw / Mn value of the low softening point substance is to 1.0, the sharper the molecular weight distribution is. Specifically, it exhibits good melting characteristics when heat is applied during fixing, bleeds quickly onto the toner surface, and shows good fixing characteristics. As a result, a synergistic effect can be obtained by combining with the above-mentioned control of the substance on the toner surface.

In the molecular weight distribution of the low softening point substance measured by GPC (gel permeation chromatography), the weight average molecular weight (Mw) and the number average molecular weight (M
If the ratio (Mw / Mn) of n) is more than 5.0, the low softening point substance will slowly exude to the toner surface and the fixing property will be deteriorated.

The molecular weight of the low softening point substance is measured by GPC under the following conditions. (GPC measurement conditions) Device: GPC-150C (Waters Co.) Column: GMH-HT 30 cm 2 stations (manufactured by Tosoh Corp.) Temperature: 135 ° C. Solvent: o-dichlorobenzene (0.1% ionol added) Flow rate: 1 0.0 ml / min Sample: 0.15% of the sample is measured under the condition of 0.4 ml injection or more, and the molecular weight calibration curve prepared from the monodisperse polystyrene standard sample is used for calculating the molecular weight of the sample. Further, it is calculated by performing polyethylene conversion using a conversion formula derived from the Mark-Houwink viscosity formula.

In the present invention, the value (Ta / Tb) of the glass transition point Ta (° C.) of the resin for the outermost layer of the toner particles and the fixing portion set temperature Tb (° C.) of the fixing device is 0.3 to 0.6. It is preferable that it is within the range.

As a result of intensive studies, the present inventors have found that, in order to fix a toner, particularly when obtaining a low gloss image which is preferred for business use, in addition to controlling the external additive, the glass transition point of the resin existing in the outermost surface layer of the toner is controlled. Found that control of is important.

Glass transition point Ta of toner particle outermost layer resin
When the ratio (Ta / Tb) of (° C.) to the fixing part set temperature Tb (° C.) of the fixing device is less than 0.3, the low temperature fixability is excellent but the high temperature offset resistance and OHT transparency are poor. become.

Glass transition point Ta of outermost layer resin of toner particles
If the ratio (Ta / Tb) of (° C.) to the fixing portion set temperature Tb (° C.) of the fixing device exceeds 0.6, the low temperature fixability will be poor.

The glass transition point of the resin is determined by DSC measurement.

In the DSC measurement, it is preferable to use a highly accurate internal heat input compensation type differential scanning calorimeter for the measurement principle. For example, DSC-7 manufactured by Perkin Elmer can be used.

The measuring method is ASTM D3418-82.
Carry out according to. In the measurement, the temperature is raised and lowered once to take a previous history, and then the temperature is raised at a temperature rate of 10 ° C./min to measure.

The crossing point between the line at the midpoint of the base line before and after the appearance of the endothermic peak and the differential heat curve is the glass transition temperature Ta in the present invention.

As the binder resin used in the toner of the present invention, the following binder resins can be used.

For example, homopolymers of styrene and its substitution products such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene; styrene-p-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene. Copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-
Styrene such as vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer -Based copolymer; polyvinyl chloride; phenolic resin; natural modified phenolic resin; natural modified maleic acid resin; acrylic resin; methacrylic resin; polyvinyl acetate; silicone resin; polyester resin;
Polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin can be used. Examples of preferable binder substances include styrene-based copolymers and polyester resins.

Examples of the comonomer for the styrene monomer of the styrene type copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Duplex such as dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide A monocarboxylic acid having a bond or a substituted product thereof; for example, a dicarboxylic acid having a double bond such as maleic acid, butyl maleate, methyl maleate and dimethyl maleate and a substituted product thereof; for example, vinyl chloride, vinyl acetate, Vinyl esters such as vinyl benzoate; ethylene olefins such as ethylene, propylene and butylene; vinyl ketones such as vinyl methyl ketone and vinyl hexyl ketone; for example vinyl methyl ether , Vinyl ethyl ether, vinyl ethers such as vinyl isobutyl ether; such vinyl monomers are used alone or two or more.

The styrene-based polymer or styrene-based copolymer may be crosslinked, or may be a mixed resin of a crosslinked resin and a non-crosslinked resin.

As the crosslinking agent for the binder resin, a compound mainly having two or more polymerizable double bonds may be used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate; ,
Divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide and divinyl sulfone; and compounds having three or more vinyl groups are used alone or as a mixture.

The addition amount of the crosslinking agent is 1
0.001 to 10 parts by mass is preferable with respect to 00 parts by mass.

The toner of the present invention may contain a charge control agent.

The following substances control the toner to be negatively charged.

For example, organic metal compounds and chelate compounds are effective, and there are monoazo metal compounds, acetylacetone metal compounds, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal compounds. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol. In addition, urea derivatives, compound metal salicylic acid compounds, compound metal naphthoic acid compounds, boron compounds, quaternary ammonium salts, calixarene, silicon compounds, styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene- Examples thereof include acrylic-sulfonic acid copolymers and non-metal carboxylic acid compounds.

The following substances control the toner to be positively charged.

For example, modified products of nigrosine and fatty acid metal salts, guanidine compounds, imidazole compounds,
Tributylbenzyl ammonium-1-hydroxy-4
Naphthosulfonates, quaternary ammonium salts such as tetrabutylammonium tetrafluoroborate, and onium salts such as phosphonium salts, which are analogs thereof, lake pigments thereof, triphenylmethane dyes and lake pigments thereof (lake formation) As agents, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.), metal salts of higher fatty acids; dibutyltin oxide, dioctyltin oxide, dicyclohexyl Diorgano tin oxides such as tin oxide; Siorgano tin borates such as dibutyl tin borate, dioctyl tin borate and dicyclohexyl tin borate; Use of these alone or in combination of two or more It can be. Of these, charge control agents such as nigrosine type and quaternary ammonium salts are particularly preferably used.

These charge control agents are preferably used in an amount of 0.01 to 20 parts by mass (more preferably 0.5 to 10 parts by mass) with respect to 100 parts by mass of the resin component.

The colorant used in the present invention is carbon black as a black colorant, and a color tone adjusted to black using the following yellow / magenta / cyan colorants is used.

As the yellow colorant, condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
Azo metal complexes, methine compounds, compounds represented by allylamide compounds and the like are used. Specifically, C.I. I.
Pigment Yellow 12, 13, 14, 15, 17, 6
2,74,83,93,94,95,109,110,
111,128,129,147,168,180 etc. are used suitably.

If desired, the yellow dye may be used alone or in combination with other pigments or dyes.

As the magenta colorant, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds and the like are used. Specifically, C.I.
I. Pigment Red 2,3,5,6,7,23,4
8: 2,48: 3,48: 4,57: 1,81: 1,1
22,146,166,169,177,184,18
5,202,206,220,221,254 are particularly preferred.

If desired, the magenta dye may be used alone or in combination with other pigments or dyes.

As the cyan colorant used in the present invention, a copper phthalocyanine compound and its derivative, an anthraquinone compound, a basic dye lake compound and the like can be used.
Specifically, C.I. I. Pigment Blue 1, 7, 15,
15: 1, 15: 2, 15: 3, 15: 4, 60,6
2, 66 and the like can be used particularly preferably.

The cyan dye may be used alone or in combination with other pigments or dyes, if necessary.

These colorants may be used alone or in combination, or in the state of solid solution. The colorant of the present invention is selected in terms of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in the toner. The amount of the colorant added is 1 to 20 parts by mass based on 100 parts by mass of the resin.

Next, a method for producing the toner used in the present invention will be described. The toner used in the present invention can be manufactured by using a pulverized toner manufacturing method and a polymerized toner manufacturing method.

In the present invention, the method for producing a pulverized toner comprises a binder resin, a low softening point substance, a pigment as a colorant, a dye or a magnetic substance, a charge control agent, if necessary, other additives, a Henschel mixer, Mix well with a mixer such as a ball mill; the resulting mixture is melt-kneaded using a heat kneader such as a heating roll, a kneader, or an extruder, and a low softening point substance in which the resin components are mutually compatible,
A pigment, a dye, and a magnetic substance are dispersed or dissolved; the obtained kneaded product is cooled and solidified, and then pulverized and classified to obtain a toner.

Further, if necessary, the toner and desired additives are thoroughly mixed with a mixer such as a Henschel mixer,
The toner used in the present invention can be obtained.

In the present invention, the method for producing a polymerized toner is, for example, a method described in Japanese Patent Publication No. 56-13945, in which a molten mixture is atomized in the air using a disk or a multi-fluid nozzle to obtain a spherical toner, and Japanese Patent Publication No. 36/36. -10231, JP-A-59-53856, JP-A-59-61
No. 842, a method of directly producing a toner by using the suspension polymerization method, or a dispersion method of directly producing a toner by using an aqueous organic solvent in which a monomer is soluble and the obtained polymer is insoluble Emulsion polymerization method represented by a soap-free polymerization method in which a toner is polymerized directly or in the presence of a water-soluble polar polymerization initiator to produce a toner, or primary polar emulsion polymerization particles are prepared in advance, and then polar particles having an opposite charge are prepared. It is possible to produce a toner by using a hetero-aggregation method or the like in which the particles are additionally associated.

However, in the dispersion polymerization method, the toner obtained has an extremely sharp particle size distribution, but the selection of materials to be used is narrow, and the use of organic solvents is related to waste solvent treatment and solvent flammability. Manufacturing equipment is complicated and easy to be complicated. The emulsion polymerization method typified by soap-free polymerization is effective because the particle size distribution of the toner is relatively uniform, but when the emulsifier or the end of the initiator used is present on the surface of the toner particles, the environmental characteristics are easily deteriorated.

Therefore, in the present invention, the suspension polymerization method under normal pressure or under pressure is particularly preferred because it can relatively easily obtain a fine particle toner having a sharp particle size distribution. A so-called seed polymerization method in which a monomer is further adsorbed to the obtained polymer particles and then the polymerization is performed using a polymerization initiator can be suitably used in the present invention.

When the direct polymerization method is used in the toner manufacturing method of the present invention, the toner can be specifically manufactured by the following manufacturing method. A low-softening point substance, a colorant, a charge control agent, a polymerization initiator and other additives are added to the monomer, and the monomer system is uniformly dissolved or dispersed by a homogenizer, an ultrasonic disperser, etc. It is dispersed in a water phase containing a conventional stirrer, a homomixer, a homogenizer or the like. Preferably, the stirring speed and time are adjusted so that the monomer droplets have a desired toner particle size, and granulation is performed. After that, stirring may be performed to the extent that the particle state is maintained and the particles are prevented from settling due to the action of the dispersion stabilizer. Polymerization temperature is 40
Polymerization is carried out at a temperature of not lower than 0 ° C, generally 50 to 90 ° C. Further, the temperature may be raised in the latter half of the polymerization reaction, and further,
In order to remove unreacted polymerizable monomers, by-products, etc. that cause odor during toner fixing, the aqueous medium may be partially distilled off in the latter half of the reaction or after the reaction.

After completion of the reaction, the produced toner particles are washed and
Collect by filtration and dry. In the suspension polymerization method,
Water is usually 300 to 3000 with respect to 100 parts by mass of the monomer system.
It is preferred to use parts by weight as the dispersion medium.

A more preferable toner used in the present invention is a direct polymerization method in which a low softening point substance is encapsulated in an outer shell resin layer by a tomographic surface measurement method of the toner using a transmission electron microscope (TEM). It is manufactured. From the viewpoint of fixability, it is necessary to include a large amount of the low softening point substance in the toner, and therefore it is necessary to encapsulate the inevitable low softening point substance in the outer shell resin. The toner that cannot be encapsulated cannot be sufficiently pulverized unless special freeze pulverization is used in the pulverization process, and as a result, only a wide particle size distribution can be obtained, and toner fusion to the device also occurs. It's very bad. Further, in the freeze pulverization, the apparatus becomes complicated due to a measure to prevent dew condensation on the apparatus, and if the toner absorbs moisture, the workability of the toner is deteriorated, and it is necessary to add a drying step, which is a problem. As a specific method for encapsulating the low softening point substance, the polarity of the material in the aqueous medium is set to be smaller for the low softening point substance than the main monomer,
Furthermore, by adding a small amount of a resin or monomer having a large polarity, a toner having a so-called core-shell structure in which a low softening point substance is coated with an outer shell resin can be obtained. Toner particle size distribution control and particle size control are carried out by changing the type and amount of dispersant that acts as a water-soluble inorganic salt or protective colloid, and mechanical device conditions such as rotor speed, number of passes, stirring blade shape. The toner of the present invention can be obtained by controlling the stirring conditions such as the above, the container shape, or the solid content concentration in the aqueous solution.

In the present invention, as a specific method for measuring the tomographic plane of the toner, the toner is sufficiently dispersed in a room temperature curable epoxy resin and then cured for 2 days in an atmosphere at a temperature of 40 ° C. After ruthenium tetraoxide and, if necessary, osmium tetraoxide are used together for dyeing, a flaky sample is cut out using a microtome equipped with diamond teeth and the toner morphology is measured using a transmission electron microscope (TEM). did. In the present invention, it is preferable to use the ruthenium tetroxide dyeing method in order to make a contrast between materials by utilizing a slight difference in crystallinity between the low softening point substance used and the resin constituting the outer shell.

A monofunctional polymerizable monomer or a polyfunctional polymerizable monomer should be used as the radically polymerizable vinyl-based polymerizable monomer used when a toner is produced by a polymerization method. You can

As the monofunctional polymerizable monomer, styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p- n-butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy Styrene-based polymerizable monomers such as styrene and p-phenylstyrene; methyl acrylate, ethyl acrylate, n-propyl acrylate,
iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate , Dimethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, 2-benzoyloxyethyl acrylate, and other acrylic polymerizable monomers; methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate,
n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, diethyl phosphate ethyl methacrylate, dibutyl phosphate ethyl Methacrylic polymerizable monomers such as methacrylate; methylene aliphatic monocarboxylic acid esters; vinyl acetate,
Vinyl propionate, vinyl benzoate, vinyl butyrate,
Vinyl esters such as vinyl benzoate and vinyl acid ester; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether (G "Tp /
G "Tp-25), vinyl-based polymerizable monomers such as vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropyl ketone.

As the polyfunctional polymerizable monomer, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6
-Hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2'-bis [4- (acryloxydiethoxy) phenyl] propane, trimethylolpropane triacrylate, tetramethylolmethane Tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate,
1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2′-bis [4- (methacryloxydiethoxy) phenyl] propane, 2,
2′-bis [4- (methacryloxy polyethoxy) phenyl] propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, divinyl ether and the like can be mentioned.

The above monofunctional polymerizable monomers may be used alone or in combination of two or more kinds, or the monofunctional polymerizable monomer and the polyfunctional polymerizable monomer may be used in combination. It is also possible to use the polyfunctional polymerizable monomer as a crosslinking agent.

In the present invention, a polar resin is preferably used in combination in order to form a core-shell structure in the toner. The polar resins such as polar polymers and polar copolymers that can be used in the present invention are exemplified below.

As the polar resin, a polymer of a nitrogen-containing monomer such as dimethylaminoethyl methacrylate or diethylaminoethyl methacrylate or a copolymer of a nitrogen-containing monomer and a styrene-unsaturated carboxylic acid ester; acrylonitrile Such as nitrile-based monomers; vinyl chloride-like halogen-based monomers; unsaturated carboxylic acids such as acrylic acid and methacrylic acid; unsaturated dibasic acids; unsaturated dibasic anhydrides; nitro-based monomers Polymers or copolymers thereof with styrene monomers; polyesters; epoxy resins. More preferable examples include copolymers of styrene and (meth) acrylic acid, maleic acid copolymers, saturated polyester resins, and epoxy resins.

Examples of the polymerization initiator include 2,2'-
Azobis (2,4-dimethylvaleronitrile), 2,
2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexasi-1-carbonitrile), 2,2 '
-Azobis 4-methoxy-2,4-dimethylvaleronitrile, azo-based or diazo-based polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butyl hydroperoxide , Di-t-butyl peroxide, dixyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis (4,4)
Peroxide initiators such as -t-butylperoxycyclohexyl) propane and tris- (t-butylperoxy) triazine, polymeric initiators having a peroxide in the side chain, potassium persulfate, ammonium persulfate and other peroxide initiators. Sulfate, hydrogen peroxide, etc. are used.

The polymerization initiator is preferably added in an amount of 0.5 to 20 parts by mass per 100 parts by mass of the polymerizable monomer, and may be used alone or in combination.

In the present invention, in order to control the molecular weight, known crosslinking agents and chain transfer agents may be added, and the preferable addition amount is 0.001 to 15 parts by mass.

In the present invention, any suitable stable dispersion medium can be used for the production of the toner by the polymerization method such as emulsion polymerization, dispersion polymerization, suspension polymerization, seed polymerization, and heterocoagulation. Use agents. For example, as the inorganic compound, tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate. , Bentonite, silica, alumina and the like. As organic compounds, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salts, starch, polyacrylamide, polyethylene oxide, poly (hydroxystearic acid-g-methacrylic acid) Methyl-eu-methacrylic acid) copolymers and nonionic or ionic surfactants are used.

When the emulsion polymerization method or the hetero-aggregation method is used, an anionic surface active agent, a cationic surface active agent, a zwitterionic surface active agent and a nonionic surface active agent are used. It is preferable to use 0.2 to 30 parts by mass of these stabilizers per 100 parts by mass of the polymerizable monomer.

When an inorganic compound is used among these stabilizers, a commercially available product may be used as it is, but the inorganic compound may be produced in a dispersion medium in order to obtain fine particles.

In order to finely disperse these stabilizers, 0.001 to 0.1 part by mass of a surfactant may be used. This is for promoting the intended action of the dispersion stabilizer, and specific examples thereof include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate,
Examples thereof include sodium oleate, sodium laurate, potassium stearate, calcium oleate and the like.

The toner of the present invention can be usually used for one-component and two-component developers. As a one-component developer,
When a non-magnetic toner containing no magnetic substance is used, there is a method in which a blade or a roller is used, and the toner is forcibly charged by friction with a developing sleeve so that the toner adheres to the sleeve for conveyance.

When used as a two-component type developer, a carrier is used together with the toner of the present invention to be used as a developer. The magnetic carrier is composed of an element consisting of iron, copper, zinc, nickel, cobalt, manganese, and chromium elements alone or in a composite ferrite state. The shape of the magnetic carrier may be spherical, flat or amorphous. Furthermore, the fine structure of the surface state of the magnetic carrier particles (eg surface irregularity)
Is also preferably controlled. Generally, a method is used in which the above-mentioned inorganic oxide is fired and granulated to generate magnetic carrier core particles in advance and then coated on a resin. From the viewpoint of reducing the load on the toner of the magnetic carrier, after kneading the inorganic oxide and the resin, pulverizing and classifying to obtain a low-density dispersed carrier, and further, directly kneading the inorganic oxide and the monomer It is also possible to use a method of obtaining a spherical spherical magnetic carrier by suspension polymerization in an aqueous medium.

A coated carrier in which the surface of the carrier particles is coated with a resin is particularly preferable. As the method, a method in which a resin is dissolved or suspended in a solvent and applied and then attached to a carrier, or a method in which a resin powder and carrier particles are simply mixed and attached can be applied.

The substance adhered to the surface of the carrier particles varies depending on the toner material, but for example, polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, styrene resin, acrylic resin, polyamide. , Polyvinyl butyral, amino acrylate resin and the like. These are used alone or in plural.

The average particle size of these carriers is preferably 1
The thickness may be 0 to 100 μm, more preferably 20 to 50 μm.

When a two-component developer is prepared by mixing the toner of the present invention with a magnetic carrier, the mixing ratio is 2 to 15% by mass, preferably 4 as the toner concentration in the developer.
Good results are usually obtained when the amount is -13% by mass.

Next, an image forming apparatus preferable for the present invention will be shown.

(1) Example of image forming apparatus FIG. 1 is a schematic configuration diagram of an example of the image forming apparatus. The image forming apparatus of this example is an electrophotographic color printer.

Reference numeral 101 denotes a photosensitive drum (image bearing member) made of an organic photosensitive member or an amorphous silicone photosensitive member,
Predetermined process speed (peripheral speed) in the counterclockwise direction indicated by the arrow
It is driven to rotate. The photosensitive drum 101 is uniformly charged with a predetermined polarity and potential by a charging device 102 such as a charging roller during its rotation process.

Next, the laser beam 103 output from the laser optical box (laser scanner) 110 is applied to the charged surface.
Subject to scanning exposure processing of target image information. The laser optical box 110 is a laser beam 10 modulated (on / off) in response to a time series electric digital pixel signal of target image information from an image signal generator such as an image reading device (not shown).
3 is output to form an electrostatic latent image on the surface of the rotary photosensitive drum 101, which corresponds to the target image information scanned and exposed. 10
Reference numeral 9 is a mirror for deflecting the output laser light from the laser optical box 110 to the exposure position of the photosensitive drum 101.

In the case of forming a full-color image, scanning exposure / latent image formation is performed on the first color-separated component image of the target full-color image, for example, the yellow component image, and the latent image of the four-color developing device 104 is used. By the operation of the yellow developing device 104Y, a yellow toner image is developed. The yellow toner image is transferred onto the surface of the intermediate transfer drum 105 at the primary transfer portion T1 which is a contact portion (or a proximity portion) between the photosensitive drum 101 and the intermediate transfer drum 105. The surface of the rotary photosensitive drum 101 after the toner image is transferred onto the surface of the intermediate transfer drum 105 is the cleaner 1.
At 07, the transfer residual toner and other adhering residues are removed and cleaned.

The process cycle of charging, scanning exposure, development, primary transfer, and cleaning as described above is performed by the second color separation component image (for example, magenta component image) of the target full-color image.
Magenta developing device 104M operates), third color separation component image (for example, cyan component image, cyan developing device 104C operates), and fourth color separation component image (for example, black component image, black developing device 104BK operates) The color separation component images are sequentially executed, and the four color toner images of the yellow toner image, the magenta toner image, the cyan toner image, and the black toner image are sequentially superimposed and transferred to the surface of the intermediate transfer body drum 105 to obtain the target full-color image. A color toner image corresponding to is formed.

The intermediate transfer drum 105 has a medium resistance elastic layer and a high resistance surface layer on a metal drum, and is in contact with or in close proximity to the photosensitive drum 101 and has a peripheral speed substantially the same as that of the photosensitive drum 101. Is rotated clockwise as indicated by the arrow, and a bias potential is applied to the metal drum of the intermediate transfer body drum 105 to generate a toner image on the side of the photosensitive body drum 101 by a potential difference from the photosensitive body drum 101.
Troublesome transfer.

The color toner image synthetically formed on the surface of the rotary intermediate transfer drum 105 is subjected to the secondary transfer at the secondary transfer portion T2 which is a contact nip portion between the rotary intermediate transfer drum 105 and the transfer roller 106. The image is transferred onto the surface of the recording material P fed into the transfer portion T2 from a paper feeding portion (not shown) at a predetermined timing. The transfer roller 106 supplies a charge having a polarity opposite to that of the toner from the back surface of the recording material P to sequentially transfer the composite color toner image from the surface of the intermediate transfer drum 105 to the recording material P side in order.

The recording material P passing through the secondary transfer portion T2 is separated from the surface of the intermediate transfer body drum 105 and introduced into the image heating device (fixing device) 100, and subjected to the heat fixing process of the unfixed toner image. The color image formed product is ejected to a paper ejection tray (not shown) outside the apparatus. The fixing device 100 will be described in detail in the next section (2).

After the transfer of the color toner image onto the recording material P, the rotary intermediate transfer drum 105 is cleaned by the cleaner 108 after removing the transfer residual toner, adhering residues such as paper dust and the like.

The cleaner 108 is normally held in a non-contact state with the intermediate transfer body drum 105, and in the process of executing the secondary transfer of the color toner image from the intermediate transfer body drum 105 to the recording material P, the intermediate transfer body drum 105 is carried out. Be held in contact with.

The transfer roller 106 is also always held in a non-contact state with the intermediate transfer body drum 105, and in the process of executing the secondary transfer of the color toner image from the intermediate transfer body drum 105 to the recording material P, the intermediate transfer body drum 105 is executed. 105
Is held in contact with the recording material P via the recording material P.

The apparatus of this example can also execute a print mode of a monochrome image such as a monochrome image. Also, a double-sided image print mode or a multiple image print mode can be executed.

In the case of the double-sided image print mode, the recording material P on which the first image has been printed out of the image heating apparatus 100 has been printed.
Is turned upside down via a recirculation conveyance mechanism (not shown) and is sent to the secondary transfer portion T2 again to receive the toner image transfer on the two surfaces, and is again introduced into the image heating device 100 and is transferred to
A double-sided image print is output by receiving the fixing process of the toner image on the surface.

In the case of the multiple image print mode, the recording material P, which has exited the image heating apparatus 100 and has undergone the first image print, is printed.
Is fed to the secondary transfer portion T2 again without being turned upside down via a recirculation transport mechanism (not shown), and receives the second toner image transfer on the surface on which the first image printing has been performed, and the image heating device 100 again. When the toner image is introduced into the printer and undergoes the second toner image fixing process, a multiple image print is output.

(2) Fixing Device (Heating Unit) 100 In this example, the fixing device 100 is an electromagnetic induction heating type device. FIG. 2 is a cross-sectional side view model view of a main part of the fixing device 100 of the present embodiment, FIG. 3 is a front view model view of the main part, and FIG.

The apparatus 100 of this embodiment is similar to the fixing device of FIG.
It is a pressure roller driving type and electromagnetic induction heating type device that uses a cylindrical electromagnetic induction heating belt. The same components and parts as those of the apparatus shown in FIG. 9 are designated by the same reference numerals, and the description thereof will be omitted.

The magnetic field generating means is the magnetic cores 17a, 17b.
17c and an exciting coil 18.

The magnetic cores 17a, 17b, and 17c are members of high magnetic permeability, and materials such as ferrite and permalloy used for the core of the transformer are preferable, and more preferably ferrite with less loss even at 100 kHz or more is preferable.

The exciting coil 18 has power feeding portions 18a and 18b.
An exciting circuit 27 (FIG. 5) is connected to the. The excitation circuit 27 is capable of generating a high frequency of 20 kHz to 500 kHz with a switching power supply.

The exciting coil 18 generates an alternating magnetic flux by the alternating current (high frequency current) supplied from the exciting circuit 27.

The fixing belts 16a and 16b are gutter-shaped belt guide members having a substantially semi-circular cross section, which form a substantially cylindrical body with their opening sides facing each other and are cylindrical electromagnetic induction heating belts on the outside. 10 is loosely fitted.

The belt guide member 16a holds the magnetic cores 17a, 17b and 17c as the magnetic field generating means and the exciting coil 18 inside.

Further, the belt guide member 16a has a structure shown in FIG.
As shown in FIG. 3, a good heat conducting member 40 having a longitudinal direction perpendicular to the paper surface is provided inside the fixing belt 10 on the side of the nip portion N facing the pressure roller 30.

In this example, the good heat conductive member 40 is made of aluminum. The good thermal conductive material 40 has a thermal conductivity k of k = 240 [W · m ⁻¹ · K ⁻¹ ], and a thickness of 1
[Mm]. Further, the good heat conducting member 40 includes the exciting coil 18 and the magnetic cores 17a, 17b, 1 which are magnetic field generating means.
It is arranged outside this magnetic field so as not to be affected by the magnetic field generated from 7c.

Specifically, the good heat conducting member 40 is arranged at a position separated from the exciting coil 18 by the magnetic core 17c,
The good heat conductor 40 is not affected by being located outside the magnetic path formed by the exciting coil 18.

Reference numeral 22 is a laterally long pressurizing stay which is disposed in contact with the flat surface of the inner surface of the belt guide member 16b.

Reference numeral 19 denotes an insulating member for insulating the magnetic cores 17a, 17b, 17c and the exciting coil 18 from the pressurizing rigid stay 22.

The flange members 23a and 23b are externally fitted to the left and right ends of the assembly of the belt guide members 16a and 16b, and are rotatably attached while fixing the left and right positions. When the fixing belt 10 is rotated, the ends of the fixing belt 10 are rotated. When the fixing belt is received, the fixing belt serves to regulate the deviation of the fixing belt along the longitudinal direction of the belt guide member.

The pressure roller 30 as a pressure member is made of a heat-resistant and elastic material such as silicone rubber, fluororubber, or fluororesin, which is formed by concentrically forming a core around the core metal 30a in a roller shape. And a layer 30b, and both ends of the cored bar 30a are rotatably supported by bearings between chassis side metal plates (not shown) of the apparatus.

By compressing the pressing springs 25a and 25b between the both ends of the pressing rigid stay 22 and the spring receiving members 29a and 29b on the apparatus chassis side, a pressing force is applied to the pressing component stay 22. ing. As a result, the lower surface of the belt guide member 16a and the upper surface of the pressure roller 30 are pressed against each other with the fixing belt 10 sandwiched therebetween to form a fixing nip portion N having a predetermined width.

The pressure roller 30 is rotationally driven by the driving means M in the counterclockwise direction indicated by the arrow. A rotational force acts on the fixing belt 10 by the frictional force between the pressure roller 30 and the outer surface of the fixing belt 10 due to the rotational driving of the pressure roller 30, and the inner surface of the fixing belt 10 has good heat conduction in the fixing nip N. The belt guide members 16a and 16b are rotated around the outer circumference of the belt guide members 16a and 16b in a clockwise direction indicated by an arrow at a peripheral speed substantially corresponding to the peripheral speed of rotation of the pressure roller 30 while closely sliding on the lower surface of the member 40.

In this case, in order to reduce the mutual sliding frictional force between the lower surface of the good heat conducting member 40 and the inner surface of the fixing belt 10 in the fixing nip portion N, the lower surface of the good heat conducting member 40 in the fixing nip portion N is A lubricant such as heat resistant grease may be interposed between the inner surface of the fixing belt 10 and the lower surface of the good heat conductive member 40 may be covered with a lubricating member.
This is because the sliding fixing belt 10 is damaged and the fixing belt 10 is damaged when the surface slipperiness is not good in terms of material or the finishing process is simplified as in the case where aluminum is used as the good heat conduction member 40. It is intended to prevent deterioration of durability of the.

The good heat conductive member 40 has an effect of making the temperature distribution in the longitudinal direction uniform. For example, when a small size paper is passed, the heat quantity of the non-paper passing portion of the fixing belt 10 is good. The heat is transferred to the heat transfer member 40, and the heat transfer in the longitudinal direction of the good heat transfer member 40 transfers the heat quantity of the non-sheet passing portion to the small size sheet passing portion. As a result, it is possible to obtain an effect of reducing power consumption when passing small size paper.

Further, as shown in FIG. 5, the belt guide member 16a is provided with convex rib portions 16e formed on the peripheral surface thereof at predetermined intervals along the length thereof.
The contact sliding resistance between the peripheral surface of a and the inner surface of the fixing belt 10 is reduced to reduce the rotational load of the fixing belt 10.
Such a convex rib portion can be similarly formed and provided on the belt guide member 16b.

FIG. 6 schematically shows how alternating magnetic flux is generated. The magnetic flux C represents a part of the generated alternating magnetic flux.

The alternating magnetic flux (C) guided to the magnetic cores 17a, 17b, and 17c is the magnetic core 17a and the magnetic core 17b.
Eddy current is generated in the electromagnetic induction heating layer 1 of the fixing belt 10 between the magnetic core 17a and the magnetic core 17c. This eddy current causes Joule heat (eddy current loss) in the electromagnetic induction heating layer 1 due to the specific resistance of the electromagnetic induction heating layer 1. The heat generation amount Q here is determined by the density of the magnetic flux passing through the electromagnetic induction heat generation layer 1 and has a distribution as shown in the graph of FIG. In the graph of FIG. 6, the vertical axis represents the position in the circumferential direction of the fixing belt 10 represented by an angle θ with the center of the magnetic core 17a as 0, and the horizontal axis represents heat generation in the electromagnetic induction heating layer 1 of the fixing belt 10. The quantity Q is shown. Here, the heat generation region H is defined as a region where the heat generation amount is Q / e or more, where Q is the maximum heat generation amount. This is an area where the amount of heat generated for fixing can be obtained.

The temperature of the fixing nip portion N is adjusted so that a predetermined temperature is maintained by controlling the current supply to the exciting coil 18 by a temperature adjusting system including a temperature detecting means (not shown). Reference numeral 26 denotes a temperature sensor such as a thermistor that detects the temperature of the fixing belt 10. In this example, the temperature of the fixing nip portion N is controlled based on the temperature information of the fixing belt 10 measured by the temperature sensor 26. There is.

Then, the fixing belt 10 rotates, and the electromagnetic induction heat of the fixing belt 10 is generated by the power supply from the exciting circuit 27 to the exciting coil 18, so that the fixing nip portion N rises to a predetermined temperature. In the temperature-controlled state, the unfixed toner image t conveyed from the image forming unit is
The recording material P on which the image is formed is introduced between the fixing belt 10 and the pressure roller 30 in the fixing nip portion N so that the image surface is directed upward, that is, facing the fixing belt surface. The fixing belt 10 is brought into close contact with the outer surface of the fixing belt 10 and is conveyed through the fixing nip portion N together with the fixing belt 10. While the recording material P is nipped and conveyed in the fixing nip portion N together with the fixing belt 10, the unfixed toner image t on the recording material P is heated and fixed by being heated by electromagnetic induction heat generation of the fixing belt 10. It When the recording material P passes through the fixing nip portion N, it is separated from the outer surface of the rotary fixing belt 10 and discharged and conveyed. The heat-fixed toner image on the recording material passes through the fixing nip portion and is cooled to become a permanently fixed image.

In this example, as shown in FIG. 2, a thermostat which is a temperature detecting element is provided at a position facing the heat generating area H (FIG. 6) of the fixing film 10 so as to cut off the power supply to the exciting coil 18 at the time of a runaway. A switch 50 is provided.

FIG. 7 is a circuit diagram of the safety circuit used in this example. Thermo switch 50, which is a temperature detection element, has a +24
It is connected in series with the VDC power supply and the relay switch 51, and when the thermo switch 50 is turned off, the relay switch 5
The power supply to 1 is cut off, the relay switch 51 operates,
The power supply to the excitation circuit 27 is cut off, so that the power supply to the excitation coil 18 is cut off. The OFF operating temperature of the thermoswitch 50 was set to 220 ° C.

Further, the thermoswitch 50 is disposed so as to face the heat generating area H of the fixing film 10 and not contact the outer surface of the fixing film 10. Thermo switch 50 and fixing film 1
The distance to 0 was about 2 mm. As a result, the fixing film 10 is not scratched by the contact of the thermoswitch 50, and deterioration of the fixed image due to durability can be prevented.

According to this example, unlike the structure in which heat is generated in the fixing nip N as shown in FIG. 10 when the fixing device is out of control due to a device failure, the fixing device is stopped when the paper is caught in the fixing nip N, and excitation is performed. The power is continuously supplied to the coil 18 and the fixing film 10
Even if the paper continues to generate heat, the paper is not directly heated because the fixing nip portion N where the paper is sandwiched does not generate heat. Further, since the thermoswitch 50 is disposed in the heat generation area H where the heat generation amount is large,
When 20 ° C. is sensed and the thermoswitch is turned off, the relay switch 51 cuts off the power supply to the exciting coil 18.

According to this example, the ignition temperature of paper is about 400.degree.
Since it is in the vicinity, the heat of the fixing film can be stopped without the paper igniting.

As the temperature detecting element, a temperature fuse may be used instead of the thermoswitch.

In this example, since the toner containing the low-softening substance was used as the toner t, the fixing device was not provided with an oil coating mechanism for preventing offset, but the toner containing no low-softening substance was used. In some cases, an oil application mechanism may be provided. Further, even when a toner containing a low softening substance is used, oil application or cooling separation may be performed.

A) Exciting Coil 18 The exciting coil 18 uses a bundle of a plurality of thin copper wires, each of which is insulation-coated, as a conductor (electric wire) constituting a coil (a coil). This is wound a plurality of times to form an exciting coil. In this example, the exciting coil 18 is formed by winding 10 turns.

As the insulating coating, a coating having heat resistance is preferably used in consideration of heat conduction due to heat generation of the fixing belt 10.
For example, a coating such as amide imide or polyimide may be used.

The exciting coil 18 may be applied with pressure from the outside to improve the density.

The exciting coil 18 is shaped so as to follow the curved surface of the heat generating layer as shown in FIG. In this example, the distance between the heat generating layer of the fixing belt and the exciting coil 18 is set to be about 2 mm.

The material for the exciting coil holding member 19 is preferably one having excellent insulation and heat resistance. For example, a phenol resin, a fluorine resin, a polyimide resin, a polyamide resin, a polyamideimide resin, a PEEK resin, a PES resin, a PPS resin, a PFA resin, a PTFE resin, an FEP resin, an LCP resin, or the like may be selected.

[0200] The magnetic cores 17a, 17b, 17c and the exciting coil 18 and the heat generating layer of the fixing belt are closer to each other as far as possible so that the magnetic flux absorption efficiency is high. Since the efficiency is remarkably reduced, it is preferable to set it within 5 mm. If the distance is within 5 mm, the distance between the heat generating layer of the fixing belt 10 and the exciting coil 18 does not need to be constant.

Excitation coil holding member 19 of the excitation coil 18
With respect to the lead-out wires, ie, 18a and 18b (FIG. 5), an insulating coating is applied to the outside of the bundle wire in the portion outside the exciting coil holding member 19.

B) Fixing Belt 10 FIG. 8 is a schematic diagram of the layer structure of the fixing belt 10 in this example. The fixing belt 10 of this example is a heating layer 1 made of a metal belt or the like which is a base layer of the fixing belt 10 having electromagnetic induction heat generation.
And a release layer 3 laminated on the outer surface of the elastic layer 2 and the release layer 3 laminated on the outer surface thereof. A primer layer (not shown) may be provided between the layers for adhesion between the heat generating layer 1 and the elastic layer 2 and adhesion between the elastic layer 2 and the release layer 3.
In the fixing belt 10 having a substantially cylindrical shape, the heat generating layer 1 is the inner surface side and the release layer 3 is the outer surface side. As described above, the alternating magnetic flux acts on the heat generating layer 1 to cause the heat generating layer 1 to operate.
An eddy current is generated in the heat generating layer 1 to generate heat. The heat heats the fixing belt 10 through the elastic layer 2 and the release layer 3,
The recording material P as a material to be heated which is passed through the fixing nip N is heated to heat and fix the toner image.

A) Heat-generating layer 1 The heat-generating layer 1 is preferably made of a ferromagnetic metal such as nickel, iron, ferromagnetic SUS, or nickel-cobalt alloy.

A non-magnetic metal may be used, but a metal such as nickel, iron, magnetic stainless steel, cobalt-nickel alloy, etc., which absorbs magnetic flux is more preferable.

The thickness thereof is preferably thicker than the skin depth expressed by the following equation and 200 μm or less. The skin depth σ [m] is the frequency f [Hz] of the excitation circuit and the magnetic permeability μ.
And specific resistance ρ [Ωm] is expressed as σ = 503 × (ρ / fμ) ^1/2 .

This indicates the depth of absorption of electromagnetic waves used for electromagnetic induction. At deeper points, the intensity of electromagnetic waves is 1 / e or less. Conversely, most energy reaches this depth. Is absorbed in.

The thickness of the heat generating layer 1 is preferably 1 to 100 μm.
m is good. If the thickness of the heat generating layer 1 is smaller than 1 μm, most of the electromagnetic energy cannot be absorbed, resulting in poor efficiency. Further, if the heat generating layer exceeds 100 μm, the rigidity becomes too high and the bending property deteriorates, which is not practical for use as a rotating body. Therefore, the thickness of the heat generating layer 1 is 1 to 1
00 μm is preferable.

B. Elastic Layer 2 The elastic layer 2 is made of silicone rubber, fluororubber, fluorosilicone rubber or the like, which has good heat resistance and good thermal conductivity.

The thickness of the elastic layer 2 is preferably 10 to 500 μm. The elastic layer 2 has a thickness necessary to guarantee the quality of a fixed image.

When a color image is printed, a solid image is formed over a large area on the recording material P, especially for a photographic image. In this case, if the heating surface (release layer 3) cannot follow the unevenness of the recording material or the unevenness of the toner layer, uneven heating occurs, and uneven gloss occurs in the image in a portion where the heat transfer amount is large and a portion where the heat transfer amount is small. The part with a large amount of heat transfer has a high glossiness,
The gloss is low in the part where the amount of heat transfer is small. When the thickness of the elastic layer 2 is 10 μm or less, the unevenness of the image gloss is generated because the unevenness of the recording material or the toner layer cannot be followed.
Further, when the elastic layer 2 has a thickness of 1000 μm or more, the thermal resistance of the elastic layer becomes large, which makes it difficult to realize quick start. More preferably, the elastic layer 2 has a thickness of 50 to 50.
0 μm is preferable. If the hardness of the elastic layer 2 is too high, it cannot follow the irregularities of the recording material or the toner layer, resulting in uneven image gloss. Therefore, the hardness of the elastic layer 2 is 60 ° (JIS-A) or less, and more preferably 45 °.
(JIS-A) The following is preferable.

Regarding the thermal conductivity λ of the elastic layer 2, 2.5 × 10 ^{−3 to} 8.2 × 10 ⁻³ [J / cm · sec.
deg. ] Is good.

Thermal conductivity λ is 2.5 × 10 ⁻³ [J / cm ·
sec deg. When it is smaller than the above, the thermal resistance is large and the temperature rise in the surface layer (release layer 3) of the fixing belt becomes slow.

The thermal conductivity λ is 8.2 × 10 ⁻³ [J / cm ·
sec deg. ], The hardness becomes too high and the compression set deteriorates.

Therefore, the thermal conductivity λ is 2.5 × 10 ⁻³ to 8.
2 × 10 ⁻³ [J / cm · sec · deg. ] Is good. More preferably 3.3 × 10 ^{−3 to} 6.3 × 10 ⁻³ [J / c
m · sec · deg. ] Is good.

C. Release layer 3 The release layer 3 is made of fluororesin, silicone resin, fluorosilicone rubber, fluororubber, silicone rubber, PFA, P
It is possible to select a material having good releasability and heat resistance such as TFE and FEP.

The thickness of the release layer 3 is preferably 1 to 100 μm. When the thickness of the release layer 3 is less than 1 μm, there are problems that a part having poor releasability is formed due to coating unevenness of the coating film and durability is insufficient. In addition, if the release layer exceeds 100 μm, there is a problem that heat conduction is deteriorated, and particularly in the case of a resin-based release layer, the hardness becomes too high and the effect of the elastic layer 2 is lost.

D. Heat Insulating Layer Further, in the fixing belt 10 structure, a heat insulating layer may be provided on the belt guide surface side of the heat generating layer 1 (on the side opposite to the elastic layer 2 of the heat generating layer 1).

As the heat insulating layer, fluororesin, polyimide resin, polyamide resin, polyamideimide resin, PEE
K resin, PES resin, PPS resin, PFA resin, PT
Heat resistant resins such as FE resin and FEP resin are preferable.

The thickness of the heat insulation layer is 10 to 100
0 μm is preferable. When the thickness of the heat insulating layer is less than 10 μm, the heat insulating effect cannot be obtained and the durability is insufficient. On the other hand, when the thickness exceeds 1000 μm, the magnetic core 17a-1
The distance between the heating layers 1b and 7c and the exciting coil 18 becomes large, and the magnetic flux is not sufficiently absorbed by the heating layer 1.

The heat insulating layer can insulate heat generated in the heat generating layer 1 so as not to go to the inner side of the fixing belt, so that the heat supply efficiency to the recording material P side is improved as compared with the case without the heat insulating layer. . Therefore, power consumption can be suppressed.

C) Nip The fixing nip portion consisting of the rotary heating member and the pressure member in the heat fixing device of the present invention is formed with a nip having a width of 5.0 to 15.0 mm in order to secure good fixing property. Is preferred.

If the width of the fixing nip portion is less than 5.0 mm, a sufficient amount of heat for fixing the toner cannot be given when forming a full-color image.

When the width of the fixing nip portion exceeds 15.0 mm, a sufficient amount of heat for fixing the toner is provided, but high temperature offset is likely to occur during fixing.

D) Linear Pressure The pressure (linear pressure) in the fixing nip portion in the heat fixing apparatus of the present invention is 490 to 1372 N / m when the recording material is interposed.
The range of (0.5 to 1.4 kgf / cm) is preferable.

Linear pressure of 490 N / m (0.5 kgf / c
If it is less than m), the conveyance shake of the recording material is likely to occur,
Further, poor fixing occurs due to insufficient pressure, which is not preferable.

The linear pressure is 1372 N / m (1.4 kgf / c
When it exceeds m), the durability deterioration of the fixing film is significantly deteriorated, which is not preferable.

Here, the linear pressure is the pressure applied to the entire transfer material divided by the contact length.

E) Perimeter of Fixing Film 10 and Fixing Speed In this example, the perimeter of fixing film 10 which generates heat by electromagnetic induction and the time required for one rotation of fixing film 10 are set as follows. By doing so, quick start is realized and power consumption is reduced while maintaining stable fixing property.

Since the heat generating layer 1 of the fixing film 10 is thin, the heat capacity is small, and since it is metal, the heat conductivity is good, so that the heat dissipation is good. Therefore, the perimeter L of the fixing film 10
When the value exceeds 200 mm, the temperature drop during one rotation of the fixing film 10 is too large, and quick start cannot be performed. In addition, power consumption increases due to an increase in heating area with an increase in circumference. Therefore, the peripheral length L of the fixing film 10 is preferably 200 mm or less.

On the other hand, the peripheral length L of the fixing film 10 is 70 m.
When it is less than m, the curvature change becomes too large at both ends of the fixing nip portion N (upstream end and downstream end of the fixing film 10), and the durability of the fixing film 10 is significantly deteriorated. Therefore, the peripheral length L of the fixing film 10 is 70 m.
m or more is desirable.

The rotational movement speed (fixing speed) of the fixing film 10 is preferably 5 to 300 mm / sec in order to ensure both practicality and fixing property, and is 50 to 28.
0 mm / sec is more preferable.

If the rotational movement speed (fixing speed) of the fixing film 10 is less than 5 mm / sec, output will take time even if on-demand fixing is realized, which is not practical. If it exceeds 300 mm / sec, the fixing film 10
Cannot be stably rotated, and the fixing film 10
Will be damaged. Therefore, the process speed as the rotational movement speed V of the fixing film 10 is 300 mm / s.
ec or less is desirable.

FIG. 9 shows a schematic structure of an example of an electromagnetic induction heating type fixing device in which the alternating magnetic flux distribution of the exciting coil is concentrated in the fixing nip to improve the efficiency.

Reference numeral 10 is a cylindrical fixing film as an electromagnetic induction heating element having an electromagnetic induction heating layer (conductor layer, magnetic layer, resistor layer).

Reference numeral 16 denotes a gutter-shaped film guide member having a substantially semicircular cross section, and the cylindrical fixing film 10 is loosely fitted outside the film guide member 16.

Reference numeral 15 is a magnetic field generating means disposed inside the film guide member 16 and comprises an exciting coil 18 and an E type magnetic core (core material) 17.

Reference numeral 30 denotes an elastic pressure roller, which sandwiches the fixing film 10 and forms a fixing nip portion N having a predetermined width with the lower surface of the film guide member 16 with a predetermined pressure contact force so as to be in pressure contact with each other. The magnetic core 17 of the magnetic field generating means 15 is arranged at a position corresponding to the fixing nip portion N.

The pressure roller 30 is rotationally driven by the driving means M in the counterclockwise direction indicated by the arrow. The rotational force acts on the fixing film 10 by the frictional force between the pressure roller 30 and the outer surface of the fixing film 10 due to the rotational driving of the pressure roller 30,
While the inner surface of the fixing film 10 slides in close contact with the lower surface of the film guide member 16 in the fixing nip portion N, the film guide has a peripheral speed substantially corresponding to the rotational peripheral speed of the pressure roller 30 in the clockwise direction indicated by the arrow. The outer circumference of the member 176 is rotated (pressure roller driving method).

The film guide member 16 exerts pressure on the fixing nip portion, support of the exciting coil 18 as the magnetic field generating means 15 and the magnetic core 17, support of the fixing film 10, and conveyance stability of the film 10 during rotation. Play an important role. The film guide member 16 is an insulating member that does not prevent passage of magnetic flux, and is made of a material that can withstand a high load.

The exciting coil 18 generates an alternating magnetic flux by an alternating current supplied from an exciting circuit (not shown). The alternating magnetic flux is concentratedly distributed in the fixing nip portion N by the E-shaped magnetic core 17 corresponding to the position of the fixing nip portion N, and the alternating magnetic flux is generated in the electromagnetic induction heating layer of the fixing film 10 in the fixing nip portion N. Generate eddy currents. This eddy current generates Joule heat in the electromagnetic induction heating layer due to the specific resistance of the electromagnetic induction heating layer.

The electromagnetic induction heat generation of the fixing film 10 is concentratedly generated in the fixing nip portion N in which the alternating magnetic flux is concentratedly distributed, and the fixing nip portion N is heated with high efficiency.

The temperature of the fixing nip portion N is adjusted so that a predetermined temperature is maintained by controlling the current supply to the exciting coil 18 by a temperature adjusting system including a temperature detecting means (not shown).

Thus, the pressure roller 30 is rotationally driven,
Along with this, the cylindrical fixing film 10 rotates around the film guide member 16, and the electromagnetic induction heat of the fixing film 10 is generated by the power supply from the exciting circuit to the exciting coil 18, so that the fixing nip portion N is predetermined. In the state where the temperature of the recording medium P rises to the temperature and the temperature is controlled, the recording material P on which the unfixed toner image t1 is formed, which is conveyed from the image forming unit (not shown), is the fixing film 10 in the fixing nip portion N and the pressure roller 30. The image surface is introduced between the fixing film 1 and the fixing film 1 facing upward, that is, facing the fixing film surface, and the image surface is brought into close contact with the outer surface of the fixing film 10 at the fixing nip portion N.
The fixing nip portion N is nipped and conveyed together with 0. This fixing nip portion N is used together with the fixing film 10 for recording material P.
In the process of being nipped and conveyed, the unfixed toner image t1 on the recording material P is heated and fixed by being heated by the electromagnetic induction heat generation of the fixing film 10.

After passing through the fixing nip portion N, the recording material P is separated from the outer surface of the rotary fixing film 10 and discharged and conveyed.

[0245]

EXAMPLES The present invention will be described more specifically by showing examples below.

Example 1 A cyan toner used in the present invention was prepared as follows.

A 2 liter four-necked flask equipped with a high-speed stirrer TK-Homomixer was charged with ion-exchanged water 910.
Part by mass and 0.1 mol / liter-Na ₃ PO ₄ aqueous solution 45
Add 0 parts by mass and adjust the rotation speed to 12,000 rotations, and
It was heated to 5 ° C. 1.0 mol / l-C here
68 parts by mass of an aCl ₂ aqueous solution was gradually added to prepare a dispersion medium system containing a minute water-soluble dispersant Ca ₃ (PO ₄ ) ₂ .

On the other hand, the dispersoid system comprises: styrene monomer 165 parts by mass n butyl acrylate monomer 35 parts by mass phthalocyanine pigment 15 parts by mass (CI Pigment Blue 15: 3) saturated polyester resin 10 parts by mass (bisphenol Polycondensate of A and terephthalic acid, acid value 10, glass transition point 65 ° C.) Dialkyl salicylate metal compound 2 parts by mass Divinylbenzene 0.4 parts by mass Low softening point substance 20 parts by mass (monoester wax Mw = 550, Mn) = 420, Mw / Mn = 1.3) After the above mixture was dispersed for 3 hours using an attritor,
A dispersion containing 5 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was added to the above dispersion medium and granulated for 12 minutes while maintaining the rotation speed. After that, the stirrer was replaced with a propeller stirring blade from the high-speed stirrer, the internal temperature was raised to 65 ° C., the polymerization was continued at 50 rpm for 3 hours, then the temperature was raised to 85 ° C. over 1 hour, and then the polymerization was performed for 6 hours. Continued.

After completion of the polymerization, the slurry was cooled, diluted hydrochloric acid was added to dissolve the dispersant, and the mixture was filtered, washed with water and dried to obtain cyan particles (1). When the circularity distribution and particle size distribution of the obtained cyan particles (1) were measured using a flow type particle image measuring device, the average circularity was 0.975 and the maximum equivalent circle diameter was 6.5 μm. there were. The content of particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm was 13% by number.

100 parts by mass of the obtained cyan particles (1) were hydrophobized with a silane coupling agent to obtain a fine titania powder (A having a BET specific surface area of 115 m ² / g).
-1) is 1.0 part by mass, and the BET specific surface area subjected to hydrophobic treatment with a silane coupling agent is 55 m ² / g.
1.0 part by mass of silica fine powder (B-1) was added and uniformly dispersed using a Henschel mixer manufactured by Mitsui Mining Co., Ltd. to obtain cyan toner (1). The physical properties are shown in Table 1.

The above silica fine powder (B-1) had a plurality of primary particles having an average primary particle size of about 40 nm in a 100,000 times magnified photograph by a transmission electron microscope and a 100,000 times magnified photograph by a scanning electron microscope. It was confirmed that the particles were coalesced. The particle shape of the silica fine powder (B-1) confirmed from this enlarged photograph is shown in FIG.

[0252] In a magnified photograph of cyan toner (1) with a scanning electron microscope at a magnification of 500,000 times, the titania fine powder (A
-1) the primary particles have a number average major axis of 12 nm, and the composite particles of silica fine powder (B-1) have a number average major axis of 140 n in a 50,000 times enlarged photograph by a scanning electron microscope.
m was confirmed.

The fixing characteristics of the obtained cyan toner (1) were evaluated by the following evaluation items.

[Measurement Method for Evaluation Items] Using cyan toner (1), a belt-shaped toner having a toner carrying amount of 1.2 mg / cm ² on the leading edge of recording paper having a basis weight of 75 or 80 g / m ² is undetermined. A formed image was formed, and a fixing test was conducted at a process speed of 100 mm / sec using the fixing device shown below. The fixing evaluation results are shown in Table 3.

Further, using cyan toner (1), OH
A belt-shaped cyan toner image is formed on the P sheet (CG3700 manufactured by 3M Co., Ltd.) with the toner carrying amount changed to 0.2 to 1.0 mg / cm ² , and the process speed is set to 30 mm / sec with the fixing device shown below. And then settled. The fixing evaluation results are shown in Table 3. The unfixed image is prepared and the fixing property test is performed under normal temperature and normal humidity (23 ° C./60%) unless otherwise specified.

The structure of the fixing device is the heat fixing device shown in FIG. 2 (transverse side view), FIG. 3 (front view), and FIG. 4 (longitudinal front view), and the oil applying mechanism is omitted.

Magnetic cores 17a, 17 which are magnetic field generating means
b and 17c are ferrites, and the exciting coil 18 is formed by winding a bundle wire for 10 turns.

The fixing belt has a layer structure shown in FIG. 8, and the heat generating layer 1 is a nickel layer having a thickness of 10 μm.

The elastic layer 2 was made of silicone rubber having a thickness of 200 μm and having a hardness of 35 degrees in accordance with <JIS K-6301>.

Further, the release layer 3 was coated with PFA resin to have a thickness of 20 μm.

As the pressure roller 30, a core metal 3 made of Fe is used.
A roller having a roller hardness of 60 degrees (Asker-C 500 g) coated with silicone rubber and PFA resin was used.

As the pressing force, the pressure springs 25a and 25b are used.
Adjust the linear pressure to 6 with the paper of 80 g / cm ²
The pressure was 86 N / m (0.7 kgf / cm), and the fixing nip was 8 mm.

(Fixing start temperature) The unfixed image produced by the above method is heated at a temperature of the fixing unit heating section of 100 to 230 ° C.
The temperature of the image is fixed every 5 ° C in the temperature range of 0 ° C, and the obtained fixed image is rubbed twice with sillbon paper applied with a weight of 4.9 kPa (50 g / cm ² ), before and after rubbing. The temperature at which the density decrease rate is 10% or less is the fixing start temperature.

The following four ranks were evaluated according to the degree. a: The fixing start temperature is less than 140 ° C. b: The fixing start temperature is 140 ° C. or more and less than 150 ° C. c: The fixing start temperature is 150 ° C. or more and less than 160 ° C. d: The fixing start temperature is 160 ° C. or more

(High temperature offset resistance) Raise the fixing temperature,
The highest temperature at which the offset phenomenon does not occur visually is taken as the high temperature offset free temperature, and is used as an index of offset resistance.

The following four ranks were evaluated according to the degree. a: High temperature offset free temperature is 210 ° C or higher b: High temperature offset free temperature is 200 ° C or higher and 210 ° C
Less than c: High temperature offset free temperature is 190 ° C or more and 200 ° C
Less than d: High temperature offset free temperature is less than 190 ° C

(Fixing Stability) The unfixed images prepared by the above method are continuously fed through 10,000 sheets under the condition that the heating portion temperature is 170 ° C., and the fixing properties of the first sheet and 10,000 sheets are confirmed. To do. The obtained fixed image is 4.9 kPa (50 g / c
It is assumed that the sillbon paper applied with the weight of m ² ) is rubbed twice, and if the image density reduction rate before and after the rub is 10% or less, the image is fixed.

In Example 13 using the toner (13) in which the glass transition point of the outermost surface layer resin was changed, the heating section set temperature was 160 ° C., and in Example 14 using the toner (14), the heating section was set. The same test was conducted by changing the conditions to a temperature of 180 ° C.

The following four ranks were evaluated according to the degree. a: Initially, fixing is performed after 10,000 sheets have been passed, and the reduction rate is 10% or less. b: The image is fixed in the initial stage, but after the 10,000 sheets have passed, no offset occurs, but the density reduction rate is 10% or more. c: The image is fixed in the initial stage, but after 10,000 sheets have passed, it is offset, and the back surface is soiled. d: Initially offset.

(Evaluation of scratches on the surface layer of the fixing belt) 1000 sheets of unfixed images prepared by the above method were continuously passed under the condition that the temperature of the heating section was set at 170 ° C., and the scratches on the surface layer of the fixing belt were evaluated. It was

In Example 13 using the toner (13) in which the glass transition point of the outermost surface layer resin was changed, the heating section set temperature was 160 ° C., and in Example 14 using the toner (14), the heating section was set. The same test was conducted by changing the conditions to a temperature of 180 ° C.

The following four ranks were evaluated according to the degree. a: No scratch on the surface and no change in glossiness. b: There are no scratches on the surface, but the glossiness is reduced. c: The glossiness of the surface is lowered and fine scratches are partially seen. d: A scratch is seen on the entire surface.

(Measurement of Image Glossiness) The glossiness measuring device used in the present invention is PG-3D manufactured by Nippon Denshoku Industries Co., Ltd.
(Incident angle θ = 750) and the standard surface has a glossiness of 96.
9 black glass was used. As a chart, Xer
OX 4024 paper (75g paper) or CLC-S
Nine solid patch unfixed images of 30 mm × 30 mm size were output on K paper (manufactured by Canon Inc.).

(Image gloss difference) 402 manufactured by Xerox
4 sheets (75g sheet, Leger size) or CLC-
30mm x 30 on SK A3 size paper (made by Canon)
9 mm size solid patch images were output, and paper was passed under the conditions of a heating part set temperature of 170 ° C. and a process speed of 100 mm / sec.

In Example 13 using the toner (13) in which the glass transition point of the outermost layer resin was changed, the heating section set temperature was 160 ° C., and in Example 14 using the toner (14), the heating section was set. The same test was conducted by changing the conditions to a temperature of 180 ° C. From the viewpoint of the followability of the fixing temperature, the average gloss value at the three image leading end portions and the image trailing end portion 3 when one sheet is passed.
The difference in the average gloss value at each location was evaluated.

From the viewpoint of quick start property, the difference in average gloss value between the first sheet and the 50th sheet when 50 sheets were continuously fed immediately after the start was evaluated under low temperature and low humidity.

The following four ranks were evaluated according to the degree. a: Gloss difference is less than 5 b: Gloss difference is 5 or more and less than 10 c: Gloss difference is 10 or more and less than 15 d: Gloss difference is 15 or more

(Transparency) The transmittance with respect to the amount of each toner per unit area of the fixed image obtained on the OHP sheet was measured, and the toner mass per unit area was 0.60 mg / cm 2.
Transparency is evaluated using the value in ² . The method of measuring the transmittance will be described below.

The transmittance was measured by Shimadzu's own recording spectrophotometer UV.
2200 (manufactured by Shimadzu Corp.) is used, the transmittance of the OHP film alone is set to 100%, and the transmittance at the maximum absorption wavelength at 650 nm is measured for magenta toner; 550 nm for yellow toner; 410 nm for cyan toner; To do.

The following four ranks were evaluated according to the degree. a: transmittance of 70% or more b: transmittance of 60% or more and less than 70% c: transmittance of 50% or more and less than 60% d: transmittance of less than 50%

By controlling the shape of the toner and the external additives and fine particles on the surface of the toner to the values specified by the present invention, good fixing properties can be secured. Good startability, psychological comfort to the user, no fatigue even after seeing multiple sheets, uniform glossiness (gloss) even at the leading and trailing edges of the image on the heated material, and even when multiple sheets are passed. It was confirmed that it can be.

(Examples 2 and 3) Cyan toners (2) and (3) were prepared in the same manner as in Example 1 except that the amount of wax added in Example 1 was changed. The physical properties are shown in Table 1 and the evaluation results are shown in Table 3. Good results were obtained although slightly inferior to Example 1.

(Example 4) Cyan toner (4) was prepared by using the monoester wax of Example 1 as polypropylene wax (Mw = 3200, Mn = 540, Mw / Mn = 5.
Prepared in the same manner as in Example 1 except changing to 9).
The physical properties are shown in Table 1 and the evaluation results are shown in Table 3. Since the molecular weight distribution of the low softening point substance encapsulated in the toner is broad,
The bleeding at the time of fixing was delayed and the low temperature fixability and fixing stability were slightly inferior. Also, because of its high crystallinity, OHT
The result was that the permeability was slightly inferior.

(Example 5) Styrene-n-butyl acrylate-divinylbenzene copolymer 100 parts by mass (glass transition point 65 ° C) Phthalocyanine pigment 7 parts by mass (CI Pigment Blue 15: 3) Saturated polyester resin 5 parts by mass Parts (polycondensate of bisphenol A and terephthalic acid, acid value 10, glass transition point 65 ° C.) Dialkyl salicylate metal compound 1 part by mass Low softening point substance 8 parts by mass (monoester wax Mw = 550, Mn = 420, Mw /Mn=1.3) The above mixture is premixed with a Henschel mixer, melt-kneaded at a temperature of 130 ° C. with a twin-screw extruder, and after cooling,
Coarse pulverization was performed using a hammer mill, and then pulverization was performed using a fine pulverizer using an air jet method. This was classified to obtain cyan particles (5).

When the circularity distribution and the particle size distribution of the obtained cyan particles (5) were measured using a flow type particle image measuring device, the average circularity was 0.938 and the maximum equivalent circle diameter was 6 It was 0.5 μm. The equivalent circle diameter is 0.6μ
The content of particles of m or more and less than 2.0 μm was 44% by number.

Further, the cyan particles (5) were treated for 2 minutes at a peripheral speed of 70 nm / s by using a surface reforming device of a system in which a rotor was rotated to give a mechanical impact force to the cyan particles (6). Obtained.

When the circularity distribution and the particle size distribution of the obtained cyan particles (6) were measured by using a flow type particle image measuring device, the average circularity was 0.956, and the maximum value of the equivalent circle diameter was 6. It was 0.5 μm. The equivalent circle diameter is 0.6μ
The content of particles of m or more and less than 2.0 μm was 37% by number.

100 parts by mass of the obtained cyan particles (6) were hydrophobized with a silane coupling agent to obtain a titania fine powder (A having a BET specific surface area of 115 m ² / g) (A
-1) is 1.0 part by mass, and the BET specific surface area subjected to hydrophobic treatment with a silane coupling agent is 55 m ² / g.
1.0 part by mass of silica fine powder (B-1) was added and uniformly dispersed using a Henschel mixer manufactured by Mitsui Mining Co., Ltd. to obtain a cyan toner (5). The physical properties are shown in Table 1 and the evaluation results are shown in Table 3.

Good results were obtained although slightly inferior to those of Example 1.

(Example 6) The cyan toner (6) was replaced with the silica fine powder (B-1) of Example 1, and the fine BET specific surface area was adjusted to a fine particle size, and the BET specific surface area was 105 m ² / g. Example 1 except that (B-1) was added
Prepared as in. The physical properties are shown in Table 1 and the evaluation results are shown in Table 3. Since the particle size of B-1 was small, the average major axis of the composite particles was also small, and the number of fine silica powder was increased. As a result, the low temperature fixability, offset resistance, and OHT permeability were slightly inferior.

(Example 7) The cyan toner (7) was replaced with the silica fine powder (B-1) of Example 1 and adjusted to a coarse particle size by classification, and the BET specific surface area was 18 m ² / g. It was prepared in the same manner as in Example 1 except that (B-1) was added. The physical properties are shown in Table 1 and the evaluation results are shown in Table 3. B
Since the particle size of -1 was coarse, the dispersion of the composite particles became non-uniform, and some scratches were generated on the surface layer of the fixing belt, which is a heating member.

Also, the OHT permeability was slightly inferior.

(Examples 8 and 9) For cyan toners (8) and (9), the addition amounts of the titania fine powder (A-1) and the silica fine powder (B-1) of Example 1 were changed. Prepared in the same manner as in Example 1 except for. The physical properties are shown in Table 1 and the evaluation results are shown in Table 3. Since the addition amount of the composite particles was not proper, the low temperature fixability, the offset resistance and the OHT permeability were slightly inferior.

(Examples 10 to 12) Cyan toner (1
0) to (12) are the titania fine powder (A-) of Example 1.
Example 1 was prepared in the same manner as in Example 1 except that 1) and the silica fine powder (B-1) were changed to another inorganic fine powder. The physical properties are shown in Table 1 and the evaluation results are shown in Table 3.

Since the physical properties of the external additive fine powder and the addition amount were appropriate, the same good results as in Example 1 were obtained.

(Example 13) The cyan toner (13) is
A polyester resin was prepared in the same manner as in Example 1 except that the polyester resin having a glass transition point of 65 ° C. in Example 1 was changed to a polyester resin having a glass transition point of 50 ° C. The physical properties are shown in Table 1 and the evaluation results are shown in Table 3.

Due to the low glass transition point of the toner outermost layer resin, the low temperature fixability was good, but the high temperature offset resistance and OHT permeability were slightly inferior. Further, when the temperature setting of the heating part of the heating and fixing device of Example 1 was changed to 180 ° C. and the fixing stability after 10,000 sheets of paper was confirmed, the result was rank c.

Example 14 The cyan toner (14) is
A polyester resin was prepared in the same manner as in Example 1 except that the polyester resin having a glass transition point of 65 ° C. in Example 1 was changed to a polyester resin having a glass transition point of 80 ° C. The physical properties are shown in Table 1 and the evaluation results are shown in Table 3.

Due to the high glass transition point of the toner outermost layer resin, the high temperature offset resistance was good, but the low temperature fixability was poor.

(Example 15) The cyan toner (1) was used and the thickness of the elastic layer 2 of the fixing device used in Example 1 was changed to 40.
Change to 0 μm silicone rubber and use PF for the surface layer material.
Evaluation was performed in the same manner as in Example 1 except that A was changed to FEP.

As the layer thickness of the fixing belt and the surface release layer were made of appropriate materials, the same good results as in Example 1 were obtained.

(Example 16) The cyan toner (1) was used and the thickness of the elastic layer 2 of the fixing device used in Example 1 was changed to 40.
Change to 0 μm silicone rubber and use PF for the surface layer material.
Evaluation was performed in the same manner as in Example 1 except that A was changed to RTV silicone.

Good results were obtained, although the releasability of the silicone layer was slightly inferior to that of Example 1.

(Examples 17 to 19) Magenta colorant (CI Pigment Red 202), yellow colorant (CI Pigment Yellow 17), or black colorant (grafted carbon black) was used as the colorant. Except for the above, magenta toner, yellow toner and black toner were prepared in the same manner as in Example 1.
When these toners were examined, they had physical properties very similar to those of cyan toner (1).

Cyan toner (1) is put in the developing unit 104C, magenta toner is put in the developing unit 104M, yellow toner is put in the developing unit 104Y, black toner is put in the developing unit 104BK, and the image shown in FIG. When an image output test was conducted using a forming apparatus, a good full-color fixed image was obtained.

(Comparative Examples 1 and 2) Cyan toner (15)
And (16) were prepared in the same manner as in Example 1 except that the amount of wax added in Example 1 was changed. Table 2 for physical properties
Table 4 shows the evaluation results.

In Comparative Example 1, since the low softening point substance was added in a small amount, the offset resistance was poor and the OHT permeability was also poor.

In Comparative Example 2, since the amount of the low softening point substance added was large, gloss change occurred in the image, and the result was that the OHT permeability was poor due to the extra low softening point substance.

(Comparative Example 3) Cyan toner (17) was prepared by adding 2.0 parts by mass of silica fine powder (B-1) without adding the titania fine powder (A-1) of Example 1. Prepared as in Example 1 except for the changes. The physical properties are shown in Table 2 and the evaluation results are shown in Table 4.

Due to the absence of the inorganic fine powder (A) having a small primary particle size, the dispersion of the composite particles became non-uniform and scratches were generated on the surface layer of the fixing belt which is the heating member.

Also, satisfactory results cannot be obtained for OHT transparency.

(Comparative Example 4) The cyan toner (18) was prepared by adding no silica fine powder (B-1) of Example 1 and adding the titania fine powder (A-1) to 2.0 parts by mass. Prepared as in Example 1 except for the changes. The physical properties are shown in Table 2 and the evaluation results are shown in Table 4.

Since the composite particles B are not present, the transferability of the toner is insufficient, and satisfactory results cannot be obtained for gloss stability under low humidity.

(Comparative Example 5) Cyan toner (19) was prepared by adding 1.0 part by mass of titania fine powder (A-1) to cyan particles (1) and externally adding it to silica fine powder (B). −
It was prepared by adding 1.0 part by mass of 1) to weaken the external addition strength and externally adding it. The physical properties are shown in Table 2 and the evaluation results are shown in Table 4. The average particle diameter of the composite particles (B) was too large, and scratches were generated on the surface layer of the fixing belt, which is a heating member.

(Comparative Example 6) The cyan toner (20) has a BET specific surface area of 1 obtained by subjecting the cyan particles (5) in Example 5 to a hydrophobic treatment with a silane coupling agent.
1.0 part by mass of 15 m ² / g of titania fine powder (A-1) and silica fine powder having a BET specific surface area of 55 m ² / g (B which has been hydrophobized with a silane coupling agent).
-1) was added to 1.0 part by mass and uniformly externally added using a Henschel mixer manufactured by Mitsui Mining Company. The physical properties are shown in Table 2 and the evaluation results are shown in Table 4.

Since the average circularity of the toner is small, the transferability of the toner is poor and a satisfactory result cannot be obtained in the gloss stability.

(Comparative Example 7) A cyan toner (21) was prepared by repeating classification of the cyan particles (1) in Example 1 three times to obtain cyan particles (9), which was subjected to a hydrophobic treatment with a silane coupling agent to obtain BET. Specific surface area is 115m ²
/ G of titania fine powder (A-1) 1.0 part by mass, and BE subjected to a hydrophobic treatment with a silane coupling agent
1.0 part by mass of silica fine powder (B-1) having a T specific surface area of 55 m ² / g was added and uniformly externally added using a Henschel mixer manufactured by Mitsui Mining Co., Ltd. The physical properties are shown in Table 2 and the evaluation results are shown in Table 4.

Since the content of particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm is small, the effect as a spacer is small and the release of water or the like from the transfer paper is insufficient, resulting in satisfactory fixing stability. I can't get it.

(Comparative Example 8) Cyan toner (22) was prepared in the same manner as in Example 1 except that 0.1 part by mass of sodium dodecylbenzenesulfate was added to the dispersion medium in the production of cyan particles (1). (10), 1.0 part by mass of titania fine powder (A-1) having a BET specific surface area of 115 m ² / g, which has been subjected to a hydrophobic treatment with a silane coupling agent, and a hydrophobic treatment with a silane coupling agent. 1.0 parts by mass of the silica fine powder (B-1) having a BET specific surface area of 55 m ² / g was added and uniformly externally added using a Henschel mixer manufactured by Mitsui Mining Co., Ltd. The physical properties are shown in Table 2 and the evaluation results are shown in Table 4.

Since the content of particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm is large, melting and binding between toner resins are hindered, and satisfactory results in low temperature fixability and OHT permeability cannot be obtained.

(Comparative Example 9) The cyan toner (1) was used, and the linear pressure of the fixing device used in Example 1 was 294 N / m.
Evaluation was performed in the same manner as in Example 1 with the same configuration except that (0.3 kgf / cm) was changed.

Since the pressure applied to the fixing device was too low, the low softening point substance was not sufficiently exuded, and satisfactory results were not obtained at low temperature fixability.

(Comparative Example 10) The cyan toner (1) was used to fix the fixing device used in Example 1 to the surf fixing device shown in FIG. 10 (in contact with the toner image surface in the film heating system,
And a fixing device for applying the heat of the heating means provided on the surface of the film-shaped member opposite to the surface in contact with the toner image to the toner image, the nip of 4.7 mm, the linear pressure of 490 N / m.
(0.5kgf / cm), process speed 100m
m and a fixing temperature of 170 ° C. were evaluated in the same manner as in Example 1.

Since the nip width of the fixing device is small, the low softening point substance is insufficiently exuded, and satisfactory results cannot be obtained in low temperature fixability and OHT permeability.

Further, since the followability of the temperature control of the fixing device is inferior, a problem occurs in the gloss difference at the front and rear edges of the image, the gloss difference at the time of passing a large number of sheets, and the like.

(Comparative Example 11) Using cyan toner (1), evaluation was performed in the same manner as in Example 1 except that the elastic layer 2 of the fixing device used in Example 1 was removed.

Since there is no elastic layer, the followability to irregularities of the paper and toner layer is low, uneven gloss occurs, and satisfactory results cannot be obtained for OHT transparency.

[0328]

[Table 1]

[0329]

[Table 2]

[0330]

[Table 3]

[0331]

[Table 4]

[0332]

According to the present invention, in an image forming method for forming a fixed image on a recording material by using a heating and pressure fixing device by electromagnetic induction, an average circular shape containing at least a low softening point substance and containing an appropriate amount of fine particles. By using a toner in which two or more kinds of additive fine powders having different particle diameters are externally added to high-toner toner particles, an image forming method and a fixing method excellent in quick start property and power saving can be obtained.

Further, the glossiness of the fixed image can be kept uniform, the user can be comforted psychologically, and a high quality image having excellent transparency of the overhead projector film (OHP) image can be obtained. .

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram illustrating an example of an image forming apparatus that can be applied to the present invention.

FIG. 2 is a schematic explanatory view showing a cross-sectional side view model diagram of a main part of a fixing device applicable to the present invention.

FIG. 3 is a schematic explanatory view showing a front model view of a main part of a fixing device applicable to the present invention.

FIG. 4 is a schematic explanatory view showing a cross-sectional side view model diagram of a main part of a fixing device applicable to the present invention.

FIG. 5 is a schematic explanatory view showing an excitation circuit of a fixing device applicable to the present invention.

FIG. 6 is a schematic explanatory diagram showing how alternating magnetic flux is generated in a fixing device applicable to the present invention.

FIG. 7 is a schematic explanatory diagram showing a circuit diagram of a safety circuit of a fixing device applicable to the present invention.

FIG. 8 is a schematic explanatory view showing a layer configuration model diagram of a fixing belt applicable to the present invention.

FIG. 9 is a schematic explanatory view showing an example of a fixing device applicable to the present invention.

FIG. 10 is a schematic explanatory view showing an example of a surf fixing device used in a comparative example.

FIG. 11 is a conceptual diagram of a particle shape of silica fine powder according to an example.

[Explanation of symbols]

1 heating layer 2 elastic layer 3 Release layer 4 heat insulation layer 10 fixing belt 15 Magnetic field generating means 16, 16a, 16b Film (belt) guide member 17, 17a, 17b, 17c Magnetic core 18 Excitation coil 18a, 18b power supply unit 19 Insulation member (excitation coil holding member) 22 Rigid stay for pressurization 23a, 23b Flange member 25A, 25B pressure spring 26 Temperature sensor 27 Excitation circuit 29a, 29b Spring receiving member 30 pressure roller (elastic) 30a core metal 30b elastic material layer 40 Good thermal conductive material 50 thermo switch 51 relay switch 100 Image heating device (fixing device) N fixing nip P transfer material (recording material) 101 photoconductor drum 102 charging device 104 developing device T1 primary transfer part T2 secondary transfer part

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasushi Katsuta             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Naotaka Ikeda             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F term (reference) 2H005 AA06 AA08 AA13 AA15 CA14                       CB07 CB13 EA03 EA05 EA06                       EA07 EA10                 2H033 AA02 BA12 BA25 BA58 BE03                       BE06                 3K059 AB19 AD39 CD52 CD77

Claims (13)

[Claims] 1. A rotary heating member having at least (i) a magnetic field generating means, (ii) a heat generating layer that generates heat by electromagnetic induction, an elastic layer and a release layer, and (iii) a nip with the rotary heating member. And a non-magnetic toner image on the recording material while heating the rotary heating member through the recording material. A non-magnetic toner used in an image forming method of forming a fixed image on a recording material by pressure fixing, the non-magnetic toner comprising: (a) to (d) (a) 100 parts by mass of a binder resin: Low softening point substance 5
To 40 parts by mass, at least two or more kinds of (b) external additive fine powder are added, and the external additive fine powder has a number average major axis of primary particles of 1 to 40 mm. Is at least one kind, and at least one kind of inorganic fine powder (B) having a number average major axis of 40 to 500 nm generated by combining a plurality of primary particles is added.
(C) The average circularity of the toner particles measured by a flow type particle image analyzer is 0.950 to 0.995,
(D) In the particle size distribution based on the number of toner particles measured by a flow type particle image analyzer, the equivalent circle diameter is 0.6 μm.
5 to 50% by number of particles of m or more and less than 2.0 μm,
A non-magnetic toner characterized by satisfying: 2. The inorganic fine powder (A) added to the toner has a specific surface area by nitrogen adsorption by the BET method of 50 to 150 m ² / g, which is characterized in that. Non-magnetic toner. 3. The inorganic fine powder (B) added to the toner has a specific surface area by nitrogen adsorption by the BET method of ^{20 to} 90 m ² / g, which is characterized in that. Non-magnetic toner. 4. The toner according to claim 1, wherein the toner contains 0.1 to 2.5 parts by mass of the inorganic fine powder (A) with respect to 100 parts by mass of the toner particles. The non-magnetic toner described. 5. The toner according to claim 1, wherein the toner contains 0.1 to 2.5 parts by mass of the inorganic fine powder (B) with respect to 100 parts by mass of the toner particles. The non-magnetic toner described. 6. The inorganic fine powder (A) and the inorganic fine powder (B) are selected from the group consisting of silica, alumina, titania and their sub-oxides. The non-magnetic toner according to any one of claims. 7. The non-magnetic toner according to claim 1, wherein the inorganic fine powder (A) and the inorganic fine powder (B) are hydrophobized. 8. The low softening point substance has a ratio (Mw / Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn) of 1 in a molecular weight distribution measured by GPC (gel permeation chromatography). 8. The non-magnetic toner according to claim 1, wherein the non-magnetic toner is from 0 to 5.0. 9. The ratio (Ta / Tb) of the glass transition point Ta (° C.) of the resin for the outermost layer of the toner particles and the fixing portion set temperature Tb (° C.) of the fixing device is 0.3 to 0.6. The non-magnetic toner according to claim 1, wherein the non-magnetic toner is present. 10. The toner particles are produced by a polymerization method in which a polymerizable monomer composition containing at least a polymerizable monomer and a colorant is polymerized in a solvent liquid in the presence of a polymerization initiator. The non-magnetic toner according to any one of claims 1 to 9, 11. The heating layer has a thickness of 1 to 200 μm, the elastic layer has a thickness of 10 to 500 μm, and the release layer has a thickness of 1.
˜100 μm, the width of the nip formed by the rotary heating member and the rotary pressing member is 5.0 to 15.0 mm, and the linear pressure of the rotary heating member is 490 to 1 through the recording material.
11. The image forming method according to claim 1, which is used in an image forming method for forming a fixed image at a fixing speed of 300 mm / sec or less while pressing the rotary pressing member at 372 N / m. Non-magnetic toner. 12. A rotary heating member having (i) a magnetic field generating means, (ii) at least a heat generating layer that generates heat by electromagnetic induction, an elastic layer and a release layer, and (iii) a nip with the rotary heating member. A heating / pressurizing means having at least a rotating pressurizing member, and the non-magnetic toner image on the recording material is heated by pressing the rotating pressurizing member through the recording material. In the fixing method of forming a fixed image on a recording material by pressure fixing, as the non-magnetic toner, (a) to (b) (a) 5 parts of a low softening point substance is added to 100 parts by weight of a binder resin.
To 40 parts by mass, at least two or more kinds of (b) external additive fine powder are added, and the external additive fine powder has a number average major axis of primary particles of 1 to 40 mm. Is at least one or more, and at least one or more kinds of inorganic fine powder (B) having a number average major axis of 40 to 300 mm generated by combining a plurality of primary particles are added.
(C) The average circularity of the toner particles measured by a flow type particle image analyzer is 0.950 to 0995,
(D) In the particle size distribution based on the number of toner particles measured by a flow type particle image analyzer, the equivalent circle diameter is 0.6 μm.
5 to 50% by number of particles of m or more and less than 2.0 μm,
A fixing method characterized by using a non-magnetic toner satisfying the above conditions. 13. The heating layer has a thickness of 1 to 200 μm, the elastic layer has a thickness of 10 to 500 μm, and the release layer has a thickness of 1.
˜100 μm, the width of the nip formed by the rotary heating member and the rotary pressing member is 5.0 to 15.0 mm, and the linear pressure of the rotary heating member is 490 to 1 through the recording material.
13. The fixing method according to claim 12, wherein a fixed image is formed at a fixing speed of 300 mm / sec or less while pressing the rotary pressure member at 372 N / m.