JP2003140396A - Developer kit for color image formation and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer kit for color image formation with satisfactory characteristics, in which an image of high picture quality with excellent color reproducibility or thin line reproducibility can be stably provided for a long time, sufficient image light resistance is achieved, being highly applicable even when forming a color image to simultaneously fix a plurality of tonner layers formed on a transfer member or even when using a fixing device whose use of the liquid for offset prevention is reduced. SOLUTION: In the developer kit for color image formation composed of chromatic color developers in three colors of yellow developer, magenta developer and cyan developer at least, each of chromatic color developers has a binding resin, a tonner particle containing a specific coloring agent and wax component and inorganic dust at least.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to at least a yellow developer, a magenta developer, and a cyan developer used in a recording method utilizing an electrophotographic method, an electrostatic recording method, a magnetic recording method, a toner jet method or the like. The present invention relates to a color image forming developer kit including the three color chromatic developers, and an image forming method using the color image forming developer kit.

More specifically, the present invention relates to a color image forming developer kit used in a color image recording apparatus which can be used in a copying machine, a printer, a facsimile, a plotter and the like, and an image forming method using the color image forming developer kit. It is a thing.

[0003]

2. Description of the Related Art Conventionally, as an electrophotographic method, U.S. Pat. No. 2,297,691 and JP-B-42-23910 are known.
It is known by many methods as described in Japanese Patent Publication No. 43-24748 and Japanese Patent Publication No. 43-24748. Generally, a photoconductive substance is used to form an electrical latent image on a photoconductor by various means, and then the latent image is developed with toner, and if necessary, a direct or indirect means is used to print a paper. After the toner image is transferred to the transfer material as described above, it is fixed by heating, pressurization, heating and pressurizing, or solvent vapor to obtain a fixed image. In the case of having a step of transferring a toner image, usually, a step for removing the transfer residual toner on the photoconductor is provided, and the above steps are repeated.

Particularly in full-color image formation, an electrostatic latent image is generally formed by using a chromatic color developer composed of magenta (M) toner, cyan (C) toner, yellow (Y) toner and the like and black (Bk). A multicolor image is reproduced by developing with a black developer composed of toner and superimposing toner images of respective colors.
No. 951, No. 50-776, No. 53-471.
47, 53-47175, 53-47.
No. 176, etc.

In recent years, the field of use of the image forming apparatus using the electrophotographic method as described above is not only a copying machine for simply copying an original document but also a printer as an output of a computer or a personal copy for personal use. Moreover, it is rapidly developing into plain paper faxes and the like, and various demands are increasing. Further, the copying machines are also becoming more sophisticated by digitization.
In particular, miniaturization, speeding up, and multicoloring of the image forming apparatus are remarkable, and there is a strong demand for high reliability and high resolution.

In response to the above demands, a plurality of image forming units form toner images of different colors, respectively, and these are sequentially transferred onto the same transfer material to be transferred in sequence to form a multicolor image. A full-color image forming apparatus using the method has been widely used.

FIG. 1 is a schematic explanatory view of a full-color image forming apparatus using the image forming method for forming a multicolor image as described above.

The first color image forming apparatus unit Pa, the second color image forming apparatus unit Pb, the third color image forming apparatus unit Pc, and the fourth color image forming apparatus unit Pd are provided in the main body of the full-color color image forming apparatus. The toner images of different colors are transferred by repeating the steps of (a) charging step, (b) exposure step, (c) development step, (d) transfer step, and (e) cleaning step. It is formed on the material.

In the image forming apparatus as described above, it is effective to increase transferability and resistance to mechanical stress from the apparatus by making the particle shape of the toner spherical, but the specific surface area and volume of the toner particles are Since the particle size becomes smaller, the dispersibility of the colorant inside the toner particles has an unexpected effect on matching with the fixing device.

The fixing device for fixing the toner image includes
Generally, a heat roller type heat fixing means using a heat roller as a rotary heating member and a pressure roller as a rotary pressure member (hereinafter, both are collectively referred to as a fixing roller) is used. When performing at a higher speed, a large amount of heat energy is needed instantaneously while applying a high pressure. For this reason, an unfavorable situation occurs in which the fixing device becomes large and the preheating time at the time of startup is long. From these viewpoints, it is preferable that the toner used in the image forming apparatus as described above exhibits a high sharp melt property when heated. Further, since such a toner is excellent not only in low-temperature fixability but also in color mixing property in forming a full-color image, it is possible to widen the color reproduction range of the obtained fixed image.

However, since the toner as described above generally has a high affinity with the fixing roller, it tends to cause an offset phenomenon in which the toner is transferred to the surface of the fixing roller at the time of fixing. Particularly, yellow toner on the transfer material, It remarkably occurs when forming a color image in which a plurality of toner layers of magenta toner, cyan toner and black toner are formed.

On the other hand, in order to prevent the toner from adhering to the surface of the fixing roller, for example, the surface material of the fixing roller is made of a material having excellent releasability from the toner, such as silicone rubber or fluorine resin. Further, for the purpose of preventing the offset phenomenon and the deterioration of the surface of the fixing roller, the surface of the fixing roller is coated with a thin film of an offset preventing liquid.

However, although the above method is extremely effective in preventing the offset phenomenon,
(1) Since a device for supplying the offset preventing liquid is required, the fixing device becomes complicated, which is an obstacle to designing a small and inexpensive image forming apparatus. (2) Coating The offset prevention liquid permeates into the fixing roller at the time of heating and induces peeling between the layers constituting the fixing roller, resulting in shortening the life of the fixing roller. (3) Offset to the obtained fixed image Since the prevention liquid adheres, a sticky feeling is generated, and transparency is impaired especially when a transparency film used for overhead projectors for presentations is used as a transfer material, so that desired color reproducibility is obtained. However, there is a technical problem that (4) the offset preventing liquid contaminates the inside of the image forming apparatus.

On the other hand, transfer materials used in the image forming apparatus as described above are also diversified. For example, as the type of paper used as a transfer material, not only the difference in weighing but also the material and content of raw materials and fillers are different at present. Among these transfer materials, there are various transfer material qualities, such as those in which the constituent materials are easily detached and those which are easily adhered to the constituent members of the fixing device. The fixing device is greatly affected by these transfer materials, which makes it difficult to downsize and extend the life of the fixing device.

Further, the contaminants derived from the transfer material and the toner are agglomerated and adhere to each other on the fixing roller to cause deterioration of the performance of the fixing device, or the adhered material is peeled off to impair the quality of the fixed image. Was occurring.

[0016] Specifically, recycled paper using recycled pulp obtained by deinking used paper has been widely used from the viewpoint of environmental protection and the like. However, recycled paper often contains various contaminants. For example, JP-A-3-28789, JP-A-4-65596, JP-A-4-147152, and JP-A-5-100.
As disclosed in Japanese Patent Laid-Open No. 465 and Japanese Patent Application Laid-Open No. 6-352221, the content of contaminants in recycled paper is required to enable use in the image forming apparatus as described above. Or configuration needs to be specified.

Currently, in recycled paper used for general office work, etc., the mixing ratio of recycled pulp such as newspaper waste paper exceeds 70%, and it is expected that the mixing amount will increase more and more in the future.
It is feared that it may cause the above problems. Furthermore,
When a cleaning member for removing residual toner such as fixing residue or a separating member for preventing wrapping of the transfer material is provided on the surface of the heating roller, particularly, reproduction from a medium-quality waste paper such as a newspaper or a magazine is performed. It has been confirmed that the medium-quality pulp fibers contained in the paper powder detached from the paper cause scratches and scrapes on the surface of the fixing roller, and the functions of the cleaning member and the separating member are significantly deteriorated. The phenomenon as described above tends to become a serious problem when a fixing device in which the offset preventing liquid is applied to the fixing roller in a small amount or a fixing device in which the offset preventing liquid is not applied is used.

As described above, applying the offset preventing liquid to the surface of the fixing roller of the fixing device is very useful, but it has various problems.

Considering the recent demands for smaller and lighter image forming apparatuses and the quality of the obtained fixed image, it is preferable to remove even the auxiliary device for applying the offset preventing liquid.

Under such circumstances, technical development relating to heat and pressure fixing of toner is indispensable, and some measures have been proposed for these.

Conventionally, there are many methods of adding a wax component such as low molecular weight polyethylene or polypropylene to the toner from the idea of supplying the offset prevention liquid from the toner at the time of heating without using a device for supplying the offset prevention liquid. Proposed. However, in order to exert a sufficient effect, it is necessary to add a large amount of the above-mentioned wax component to the toner. In that case, filming on the photoconductor or contamination of the surface of the toner carrier such as carrier or sleeve. Causes a new problem such as image deterioration. Also,
When the amount of the wax component added is small, it is necessary to provide a device for supplying a small amount of the offset preventing liquid or an auxiliary cleaning member such as a winding type cleaning web or a cleaning pad.
Especially in the formation of full-color images, when a transparency film is used as the transfer material, the transparency of the fixed image and the haze (cloudiness value) are caused due to the high crystallization of the wax component and the difference in the refractive index with the binder resin. The problem of aggravation remains unsolved.

Further, Japanese Patent Publication No. 52-3304, Japanese Patent Publication No. 52-3305, Japanese Patent Publication No. 57-52574, Japanese Patent Publication No. 60-217366, and Japanese Patent Publication No. 60-2.
52360, JP-A-60-252361,
JP-A-61-94062, JP-A-61-1382
59, JP 61-273554, JP 62-14166, JP 1-109359, JP 2-79860 and JP 3-505.
No. 59 and the like disclose a technique of containing a wax component in the toner, but it is difficult to highly improve various properties required for the toner simply by including the wax component in the toner. However, the matching with the image forming apparatus using the heat and pressure fixing method is not sufficient.

In the art, in order to improve the color reproducibility of a color toner image,
It is known to use various pigments and dyes as colorants.

In particular, the magenta toner is important not only for reproducing a red color, which has a high human visual sensitivity, but also for reproducing a skin color of a human image having a complicated color tone by using the yellow toner. Developability is also required.
Also, cyan toner must achieve the secondary color reproduction of blue, which is frequently used as a business color.

Conventionally, a magenta toner contains a quinacridone colorant, a thioindigo colorant, a xanthene colorant, a monoazo colorant, a perylene colorant, a diketopyrrolopyrrole colorant, or a mixture thereof. It is known to be used.

For example, JP-B-49-46951 discloses 2,9-dimethylquinacridone pigment, JP-A-55-2.
6574 discloses thioindigo pigments, and JP-A-59-
57256 discloses xanthene dyes, JP-A-11-
No. 272014 discloses a monoazo pigment, JP-A-2-2
No. 10459 proposes a toner using a diketopyrrolopyrrole pigment, and JP-B No. 55-42383 proposes a toner using an anthraquinone pigment.

However, these colorants do not meet all the conditions required for the magenta toner, and any one of the color tone of the toner, the light resistance, the charging property, and the matching with the image forming apparatus are used. There was room for improvement.

Further, in JP-A-1-22477, a quinacridone organic pigment and a xanthene dye are used in combination, and in JP-A-2-13968, a quinacridone-based and methine-based colorants are used in combination, whereby a clear magenta color is obtained. A method for obtaining a toner, improving the charging property and light resistance of the toner, and preventing dyeing on a fixing roller such as a silicone rubber roller is disclosed. Furthermore, JP-A-62-2
No. 91669 (corresponding US Pat. No. 4777105
(Patent specification), a toner using a quinacridone pigment in a mixed crystal state is proposed.

On the other hand, in JP-A-11-52625, C.I. I. Pigment Red 48 and red pigments such as clidone-based pigments having a b ^* value of -5 or less in the L ^* a ^* b ^* color system are 2 to all pigments.
A method of improving the charging property and the light resistance of the toner, and further improving the heat resistance to the fixing roller is disclosed by using a mixed ratio of 30% by weight to obtain a toner of good magenta color. .

On the other hand, it is known to use a monoazo yellow colorant, a benzimidazolone colorant, a disazo yellow colorant, or the like alone or in combination for the yellow toner.

For example, JP-A-8-262799 discloses C.I. I. Pigment Yellow 180 and the like are used to disclose a method of improving image light resistance while preventing image scattering and image fog by using a benzimidazolone colorant.

However, the above toner hardly considers the influence of the colorant on the heat fixing method, and according to the knowledge of the present inventors, reaggregation easily occurs in the toner particles. Especially when the toner particles are produced by a polymerization method, the tendency becomes remarkable. In addition, when recycled paper having a blending ratio of recycled pulp of more than 70% is used as a transfer material, or when a plurality of toner layers formed on the transfer material have to be fixed at one time, a color image is formed or a fixing roller is fixed. No consideration is given to the case where a fixing device with a small amount of offset preventing liquid applied or a fixing device to which the offset preventing liquid is not applied is used.

Further, in Japanese Patent Laid-Open No. 2000-75554 and Japanese Patent Laid-Open No. 2000-105485, C.I. I. So
There is disclosed a method of improving color reproducibility and image light resistance by using a yellow dye-based colorant typified by Lvent Yellow 162. Furthermore, JP 20
No. 00-75552 discloses C.I. I. Pigmen
toner using a condensed azo colorant represented by t Yellow 93, and JP-A-2000-75552.
Japanese Patent Laid-Open Publication No. 2003-242242 discloses a toner in which the condensed azo colorant and the yellow dye colorant are used in combination. Although the above toner has been improved with respect to the influence on the color reproducibility and the heat fixing method, it does not meet all the conditions required for reproducing a full-color image, and particularly, it is not compatible with the magenta toner. There is room for improvement in the reproducibility of the red color corresponding to the secondary color and the matching with the image forming apparatus at that time.

As described above, regarding the system design of the color image forming apparatus using the heat fixing method, there is still insufficient comprehensive comprehensive support including the colorant used in the toner.

[0035]

SUMMARY OF THE INVENTION An object of the present invention is to provide a color image forming developer kit which solves the problems of the prior art, and an image forming method using the color image forming developer kit. Especially.

That is, an object of the present invention is to stably realize a high-quality image excellent in color reproducibility and fine line reproducibility for a long period of time, achieve sufficient image light resistance, and perform electrophotographic process. , Especially when it is necessary to fix a plurality of toner layers formed on a transfer material at one time, or when a fixing device with a small amount of offset prevention liquid applied is used, it is highly applicable. It is an object of the present invention to provide a color image forming developer kit having the above characteristics and an image forming method using the color image forming developer kit.

[0037]

In view of the above, the inventors of the present invention form toner images of different colors in a plurality of image forming portions, and transfer these toner images in sequence on the same transfer material. In the image forming method for forming a multi-color image by the method, the type and blending amount of the colorant contained in the toner particles in the chromatic color developer constituting the color image forming developer kit used in the image forming method are specified. By doing so, it has been found that a high quality image can be stably realized for a long period of time and highly applicable to an electrophotographic process, and the present invention has been completed.

[0038]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to preferred embodiments of the present invention.

The color image forming developer kit of the present invention is a color image forming developer kit composed of at least three chromatic color developers, that is, a yellow developer, a magenta developer and a cyan developer. Each of the above chromatic color developers has toner particles containing at least a binder resin, a colorant and a wax component, and an inorganic fine powder.

The yellow toner particles in the yellow developer include the condensed azo pigment represented by the following structural formula (1) and C.I.
I. Solvent Yellow 9、17、2
4, ibid 31, ibid 35, ibid 58, ibid 93, ibid 100, ibid 1
02, 103, 105, 112, 162, 1
63, C.I. I. Dispers Yellow 42,
Any one selected from the group of 64, 82, 160, 201, 224 (color index
(According to the name on the plate), the total content thereof is 1 to 20% by mass, and the mass ratio of the contents is condensed azo pigment: monoazo dye = 25: 75 to 75:25.
To be prepared.

[0041]

[Chemical 7]

By incorporating the condensed azo pigment and the yellow dye in the specific ratio in the yellow toner particles, the dispersion state of the colorant in the toner particles is improved,
Not only the characteristics of the yellow toner itself are improved, but also a good full-color image can be obtained by combining with a magenta developer or a cyan developer described later.

In particular, the condensed azo pigment used is C.I.
I. Pigment Yellow 93, the same 94, the same 9
5, 128, and 166, and the yellow dye is C.I. I. Solvent
Yellow 93, 105, 112, 162,
163, C.I. I. Dispers Yellow 4
In the case of any one selected from the group of No. 2, No. 64, No. 160, No. 201, and No. 201 (each according to the name described in the fourth version of the color index), the improvement effect is further improved.

The magenta toner particles in the magenta developer contain a quinacridone pigment represented by the following structural formula (2) and a monoazo pigment represented by the following structural formula (3),
The total content is 1 to 20% by mass, and the mass ratio of the contents is quinacridone pigment: monoazo pigment = 25: 75.
˜75: 25.

[0045]

[Chemical 8] [X ₁ and X ₂ represent a hydrogen atom or a substituent selected from an alkyl group, an alkoxy group and a halogen group. ]

[0046]

[Chemical 9]

Also in the magenta toner particles, by containing the quinacridone pigment and the monoazo pigment in a specific ratio as described above, the dispersion state of the colorant in the toner particles is improved and the characteristics of the magenta toner itself are improved. In addition to the above, a good full-color image can be obtained by combining with the yellow developer and the cyan developer as described above.

In particular, the quinacridone pigment used is
C. I. Pigment Red 122, 202,
C. I. Pigment Violet 19 and / or solid solution pigments thereof, and the monoazo pigment is C.I. I. Pigment
Red 5, ibid 31, ibid 146, ibid 147, ibid 15
If it is any one selected from the group of 0, 176, 184, 185, and 269 (each is based on the name described in the fourth version of the color index), the improvement effect is more excellent.

The cyan toner particles of the cyan developer contain a phthalocyanine pigment and are prepared so that the content thereof is 1 to 10% by mass. In particular, phthalocyanine-based pigments used for toner particles of cyan developers include C.I. I.
Pigment Blue 15, ibid 15: 1, ibid 15:
2, the same as 15: 3, the same as 15: 4, and the same as 16 (each according to the name described in the fourth edition of the color index), it is not mixed with the magenta developer or the yellow developer as described above. A good full-color image can be obtained by combination.

By specifying the type and content of the colorant in the toner particles as described above, it becomes possible to improve the content state of the colorant in the toner particles and to achieve faithful color reproduction with high definition. High resolution full color image formation is performed. In addition, even when a color image is formed in which a plurality of toner layers must be fixed at the same time, or when a fixing device with a small amount of offset preventing liquid applied to a fixing roller is used, the toner particles for heat fixing do not By minimizing the effect of the colorant on the toner, it is possible to prevent the toner from remaining on the surface of the fixing member such as the fixing roller of the fixing device. The present inventors have completed the present invention by finding that color reproduction can be stably obtained.

The color image forming developer kit of the present invention includes three chromatic color developers such as a yellow developer, a magenta developer and a cyan developer, as well as other chromatic color developers for the purpose of adjusting color tone. A black developer or black developer can be added to the composition. Further, the toner particles according to the present invention can be used alone or in combination with the above-mentioned colorants other than the above-mentioned coloring agents, or in the form of a solid solution, as long as the toner characteristics are not adversely affected.

As the black colorant for the black developer, carbon black, a magnetic material, or a mixture of the above-mentioned yellow colorant / magenta colorant / cyan colorant and toned to black can be used.

The carbon black preferably used in the present invention preferably has a nitrogen adsorption specific surface area of 100 m ² / g or less. When the nitrogen adsorption specific surface area is larger than 100 m ² / g, it becomes difficult to disperse it in the toner. However, this causes a problem in the chargeability and coloring power of the toner. Further, it is not suitable for use because it affects the polymerizability of the monomer when the toner is produced by the polymerization method.

The nitrogen adsorption specific surface area of carbon black is measured according to "ASTM D3037-79".

The toner particles in the developer according to the present invention have a circle-equivalent number average diameter D1 (μm) of 2 in the number-based circle equivalent diameter-circularity scattergram measured by a flow type particle image measuring device. 10 μm, average circularity 0.950
, 0.995, the standard deviation of circularity is less than 0.040, the main component of the binder resin is styrene- (meth) acrylic resin, and the binder resin is soluble in tetrahydrofuran (THF). Of gel permeation chromatography (GPC) has a peak molecular weight of 5,000 to 5,000.
By precisely controlling the particle shape of the toner particles and the binder resin component so that the THF insoluble content is 5 to 35% by mass at 30,000, the toner characteristics can be improved in a well-balanced manner.

That is, the circle-equivalent number average diameter D1 of the toner particles
By reducing the particle size (μm) to 2 to 10 μm, and more preferably 3 to 6 μm, the reproducibility of the outline portion of an image, particularly a character image or a line pattern, is improved.

Generally, when the toner particle size is reduced, the abundance ratio of the toner of fine particles is inevitably increased, which makes it difficult to uniformly charge the toner and causes image fog, as well as matching with the image forming apparatus. It also caused trouble.

However, in the developer according to the present invention, the average circularity of the circularity frequency distribution of toner particles is 0.950 to.
0.995, preferably 0.965 to 0.995, more preferably 0.975 to 0.990,
The transferability of a toner having a small particle size, which has been difficult in the past, is significantly improved, and the developing ability for a low-potential latent image is significantly improved. In particular, the above tendency is very effective when developing a minute spot latent image of a digital system or when forming a full-color image in which a large number of transfers are performed by using an intermediate transfer member, and the matching with an image forming apparatus is also good. It will be

Further, the developer according to the present invention has a circularity standard deviation of the circularity frequency distribution of toner particles of less than 0.040,
Preferably less than 0.035, more preferably 0.015
By setting the ratio to be less than 0.030, it is possible to make the toner charge amount appropriate when forming a thin layer of toner on the toner carrier, and it is possible to greatly improve the above-mentioned problems. I can.

By the way, in general, when a toner exhibiting a specific particle size distribution or shape distribution as described above is used, a phenomenon of toner particles slipping through occurs when a thin layer of toner is formed on the surface of a toner carrier, which is often remarkable. May cause image deterioration. However, in the toner of the present invention,
By specifying the type and content of the colorant contained in the toner particles, the dispersion state of the colorant in the toner particles is improved, and the charge can be imparted to the toner quickly and uniformly. It is possible to prevent such image deterioration as described above.

The equivalent circle diameter of the toner, the circularity, and the frequency distribution thereof in the present invention are used as a simple method for quantitatively expressing the shape of toner particles. In the present invention, the flow type particle image is used. Measuring device "FPIA-1000
Type ”(manufactured by Toa Medical Electronics Co., Ltd.) and calculated using the following formula.

[0062]

[Equation 1]

Here, the "particle projection area" is the area of the binarized toner particle image, and the "perimeter of the particle projection image".
Is defined as the length of the contour line obtained by connecting the edge points of the toner particle image.

The circularity in the present invention is an index showing the degree of unevenness of the toner particles, and shows 1.000 when the toner particles are completely spherical, and the more complicated the surface shape, the more
The circularity has a small value.

In the present invention, a circle-equivalent number average diameter D1 (μ
m) and the particle size standard deviation SDd are calculated from the following equations, where di is the particle size (center value) at the dividing point i of the particle size distribution and fi is the frequency.

[0066]

[Equation 2]

[0067]

[0068]

[Equation 3]

As a specific measuring method, 10 ml of ion-exchanged water in which impure solids and the like have been removed in advance are prepared in a container, and a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant into the container. Then, 0.02 g of a measurement sample is further added and uniformly dispersed. As the dispersing means, an ultrasonic disperser "UH-50 type" (manufactured by SMT) equipped with a titanium alloy chip of 5φ as a vibrator is used, and dispersion treatment is performed for 5 minutes to obtain a dispersion liquid for measurement. . At that time, the dispersion liquid is appropriately cooled so that the temperature of the dispersion liquid does not exceed 40 ° C.

To measure the shape of the toner particles, the flow type particle image measuring device is used, and the toner particle concentration at the time of measurement is 30.
The concentration of the dispersion liquid is readjusted to be 0.00 to 10,000 particles / μL, and 1,000 or more toner particles are measured. After the measurement, the equivalent circle diameter of the toner particles, the circularity frequency distribution, and the like are obtained using this data.

Since the specific surface area of the toner particles according to the present invention is reduced by controlling the particle shape as described above, the effect of specifying the kind and content of the colorant contained in the toner particles is obtained. It will be remarkable.

The binder resin used in the toner particles of the developer according to the present invention is a styrene- (meth) acryl copolymer, a polyester resin, an epoxy resin or a styrene-butadiene copolymer which is generally used. In particular, it is preferable that the main component is a styrene- (meth) acrylic resin from the viewpoint of the affinity with the colorant as described above. In addition, tetrahydrofuran (TH
The particle shape of the toner particles and the binder resin component are precisely adjusted so that the soluble component of F) has a peak molecular weight of 5,000 to 30,000 in gel permeation chromatography (GPC) and a THF insoluble component of 5 to 35% by mass. By controlling to 1, the toner characteristics can be improved in a well-balanced manner.

In the present invention, the GPC of the THF-soluble component of the binder resin component is measured under the following conditions. The sample is used after being dispersed / dissolved in a solvent for 12 hours or more in advance and then filtered through a solvent resistant membrane filter (pore diameter: 0.45 μm).

<GPC Measurement Conditions for Soluble Content of Binder Resin Component> Device: GPC-150C (manufactured by Waters Co.) Column: shodex GPC KF-801-80
8,808P (manufactured by Showa Denko) or TSKge
l G1000H (XL) to G7000H (XL), T
Eight consecutive temperatures of SKguardcolumn (manufactured by Tosoh Corporation): 40 ° C. Solvent: THF Flow rate: 1.0 ml / min. Sample: A sample having a concentration of 0.05 to 0.6 mass% is 0.1
ml injection

In the present invention, the THF-insoluble content of the binder resin refers to the mass ratio of the resin component insoluble in THF of the resin composition in the toner particles, and represents the crosslinking ratio of the resin composition containing the crosslinking component. Although it is a standard for indicating the degree, even if the THF insoluble content is 0% by mass, it does not necessarily mean that crosslinking is not carried out. The THF-insoluble matter is defined as a value measured as follows.

That is, the toner particles are weighed in the range of 0.5 to 1.0 g (W ₁ g), placed in "Cylindrical filter paper No. 86R" (manufactured by Toyo Roshi Kaisha, Ltd.), set in a Soxhlet extractor as it is, and THF 100 to 100. Extract with 200 ml for 20 hours. Then, the soluble component extracted with THF is recovered, and its mass (W ₂ g) is determined. On the other hand, among other constituents such as pigments contained in the toner particles, THF
Of soluble components (W ₃ g) and insoluble components (W ₄ g)
g) is separately measured by a known method, and the THF insoluble content of the binder resin in the toner particles is calculated according to the following formula.

[0077]

[Equation 4]

In the method of directly obtaining toner particles by a polymerization method, a monomer for forming them is used. Specifically, styrene; styrene-based monomers such as o- (m-, p-) methylstyrene and m- (p-) ethylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate, (meth ) Propyl acrylate, butyl (meth) acrylate, octyl (meth) acrylate, (meth)
Dodecyl acrylate, stearyl (meth) acrylate,
Behenyl (meth) acrylate, (meth) acrylic acid 2-
(Meth) acrylic acid ester-based monomers such as ethylhexyl, dimethylaminoethyl (meth) acrylate, and diethylaminoethyl (meth) acrylate; ene-based monomers such as butadiene, isoprene, cyclohexene, (meth) acrylonitrile, and acrylic acid amide. A monomer is preferably used. These may be used alone or generally in the publication Polymer Handbook Second Edition III-P 139-192.
(The John Wiley & Sons company make) The theoretical glass transition temperature (Tg) is 40-75 degreeC, and it mixes and uses a monomer suitably so that it may show. If the theoretical glass transition temperature is lower than 40 ° C, problems may easily occur from the viewpoint of storage stability and durability stability of the toner, while if it exceeds 75 ° C, the fixing point of the toner may be increased to improve the fixing property and color reproduction. It causes deterioration of sex.

Further, in the present invention, it is preferable to use a crosslinking agent at the time of synthesizing the binder resin in order to improve the mechanical strength and color reproducibility of the toner particles.

Examples of the cross-linking agent used in the toner according to the present invention include difunctional benzenes such as divinylbenzene, bis (4-acryloxypolyethoxyphenyl) propane, ethylene glycol diacrylate and 1,3-butylene glycol diamine. Acrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate ,
Polyethylene glycol # 200, # 400, # 600
Each diacrylate, dipropylene glycol diacrylate, polypropylene glycol diacrylate, polyester type diacrylate (MANDA Nippon Kayaku),
And those in which the above diacrylate is replaced with methacrylate.

As the polyfunctional crosslinking agent, pentaerythritol triacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate and its methacrylate, 2,
Examples include 2-bis (4-methacryloxy, polyethoxyphenyl) propane, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate and triallyl trimellitate.

These cross-linking agents are used as the other vinyl-based monomer 1.
The amount is preferably 0.05 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 00 parts by mass.

In the present invention, a polar resin such as polyester resin or polycarbonate resin (hereinafter referred to as “polar resin”) can be used together with the above-mentioned binder resin. By adding polar resin in the toner,
It becomes easy to set the content of the colorant in the toner particles to a preferable state.

For example, in the case of directly producing a toner by a suspension polymerization method or the like which will be described later, when the polar resin as described above is added during the polymerization reaction from the dispersion step to the polymerization step, a polymerizable monomer which becomes toner particles is added. Depending on the balance between the polarities of the composition and the aqueous dispersion medium, the added polar resin may form a thin layer on the surface of the toner particles, or may be controlled so as to have a gradient from the surface of the toner particles toward the center. I can. At this time, by using a polar resin having an interaction with the colorant according to the present invention, the presence state of the colorant in the toner particles can be made into a desired form, and particularly, the acid value is 1 to 40 mgKOH. It is preferable to use a polar resin exhibiting / g.

The amount of the polar resin added is 100
It is preferable to use 1 to 25 parts by weight with respect to parts by weight,
It is more preferably 2 to 15 parts by mass. If it is less than 1 part by mass, the state of existence of the polar resin in the toner particles becomes non-uniform, and if it exceeds 25 parts by mass, the thin layer of the polar resin formed on the surface of the toner particles becomes thicker. It becomes difficult to control the contained state of the colorant, and the function cannot be sufficiently exhibited.

The above-mentioned polar resins are not limited to one kind of polymer, and for example, two or more kinds of reactive polyester resins may be used at the same time, or two or more kinds of vinyl polymers may be used. It is possible, and further, completely different types of polymers, such as non-reactive polyester resin, epoxy resin, polycarbonate resin, polyolefin, polyvinyl acetate, polyvinyl chloride, polyalkyl vinyl ether, polyalkyl vinyl ketone,
Various polymers such as polystyrene, poly (meth) acrylic ester, melamine formaldehyde resin, polyethylene terephthalate, nylon and polyurethane can be added to the binder resin as required.

As the wax component usable in the present invention, specifically, petroleum wax such as paraffin wax, microcrystalline wax, petrolactam and derivatives thereof, montan wax and derivatives thereof,
Examples include hydrocarbon waxes and their derivatives by the Fischer-Tropsch method, polyolefin waxes and their derivatives represented by polyethylene, natural waxes such as carnauba wax and candelilla wax, and their derivatives. The derivatives include oxides and vinyl monomers. Also included are block copolymers with and graft modified products. In addition, alcohols such as higher aliphatic alcohols; fatty acids such as stearic acid and palmitic acid or compounds thereof; acid amides, esters, ketones, hydrogenated castor oil and its derivatives, vegetable wax, animal wax. These can be used alone or in combination.

Among these, when polyolefin, hydrocarbon wax by the Fischer-Tropsch method, petroleum wax, higher alcohol, or higher ester is used, the effect of improving the developability and transferability is further enhanced. An antioxidant may be added to these wax components within a range that does not affect the charging property of the toner. Moreover, these wax components are used as the binder resin 100.
It is preferable to use 1 to 30 parts by mass with respect to parts by mass.

The wax component used in the present invention has a main endothermic peak temperature (melting point) of 3 in the DSC curve measured according to "ASTM D3418-82".
Compounds in the range of 0 to 150 ° C, more preferably 40 to 120 ° C, and particularly preferably 50 to 90 ° C are preferred.

By using the wax component exhibiting the thermal characteristics as described above, not only the good fixing property of the toner obtained, but also the releasing effect of the wax component is efficiently exhibited and a sufficient fixing area is secured. As a result, a color image exhibiting good color reproducibility can be obtained, and at the same time, the conventionally known wax component can eliminate the developability, blocking resistance, and adverse effects on the image forming apparatus.
In particular, since the specific surface area of the toner decreases as the particle shape of the toner becomes spherical, controlling the thermal characteristics and dispersion state of the wax component becomes very effective.

For measuring the main endothermic peak temperature (melting point) of the wax component, for example, "DSC-7" (manufactured by Perkin Elmer Co., Ltd.) is used. The melting points of iridium and zinc are used to correct the temperature of the device detection unit, and the heat of fusion of iridium is used to correct the amount of heat. At the time of measurement, set a measurement sample placed in an aluminum pan and an aluminum pan only (empty pan) for comparison,
The main endothermic peak temperature (melting point) is determined from the DSC curve obtained when the temperature in the measurement region of 180 ° C. is increased at a temperature increase rate of 10 ° C./min. When measuring only the wax component, the temperature is raised and lowered under the same conditions as the measurement to remove the previous history and then the measurement is started. Further, when measuring the wax component contained in the toner, the measurement is performed as it is without performing the operation of removing the previous history.

To the toner particles according to the present invention, a known charge control agent can be used in combination for the purpose of finely adjusting the triboelectric charge amount and the charging speed. Particularly, the charging speed is fast and the charging is constant. A charge control agent capable of stably maintaining the amount is preferable. Further, when the toner particles are directly produced by a polymerization method, a charge control agent having no polymerization inhibitory property and having no solubilized product in the aqueous dispersion medium is preferable. Specific compounds include:
Negative charge control agents such as metal compounds of carboxylic acids such as salicylic acid, naphthoic acid and dicarboxylic acid; polymeric compounds having sulfonic acid or carboxylic acid groups in the side chains; boron compounds; urea compounds; silicon compounds; currys arenes Etc. Examples of the positive charge control agent include a quaternary ammonium salt; a polymer type compound having the quaternary ammonium salt in its side chain; a guanidine compound; an imidazole compound.

The developer according to the present invention contains an inorganic fine powder together with toner particles. This improves the developability, transferability, charge stability, fluidity and durability.

As the inorganic fine powder which is preferably used in the present invention, known ones can be used, particularly silica,
It is preferred to be selected from alumina, titania or a complex oxide thereof. Furthermore, silica is more preferable. For example, as the silica, both a so-called dry method produced by vapor phase oxidation of a silicon halide or an alkoxide or a dry silica called fumed silica and a so-called wet silica produced from alkoxide, water glass or the like can be used. However, dry silica having less silanol groups on the surface and inside the silica fine powder and less production residues such as Na ₂ O and SO ₃ ²⁻ is preferable. Further, in the case of dry silica, it is also possible to obtain a composite fine powder of silica and other metal oxide by using other metal halogen compound such as aluminum chloride and titanium chloride together with the silicon halogen compound in the manufacturing process. Also includes.

The inorganic fine powder used in the present invention is BET.
The specific surface area by measuring nitrogen adsorption 30 m ² / g or more by law, in particular 50 to 400 m ² / g give good results in the range of, used 0.3 to 8 parts by mass with respect to 100 mass parts of the toner , Preferably 0.5 to 5 parts by mass.

By using the inorganic fine powder whose specific surface area is controlled as described above, the amount of water adsorbed on the toner particles can be suppressed even when a colorant is present near the toner surface, and the amount of charge and charge can be reduced. The speed control effect is increased. In addition, image defects due to contamination or abrasion of the electrostatic latent image bearing member or the intermediate transfer member by the colorant are prevented in advance.
Further, since the toner is imparted with an appropriate fluidity, the uniform charging property of the toner is synergistically improved, and the excellent effect as described above is maintained even if a large number of printouts are continuously repeated.

When the specific surface area is less than 30 m ² / g,
It is difficult to impart appropriate fluidity to the toner, and the effect of preventing the toner bearing member from being contaminated due to the colorant is reduced. When the specific surface area exceeds 400 m ² / g, the inorganic fine powder is embedded in the surface of the toner particles during continuous printing on a large number of sheets, so that the fluidity of the toner may decrease.

When the amount of the inorganic fine powder added is less than 0.3 part by mass, the effect of addition is not exhibited, and when it exceeds 8 parts by mass, the charging property and the fixing property of the toner only occur. However, the loosened inorganic fine powder significantly deteriorates the matching with the image forming apparatus.

The inorganic fine powder used in the present invention is
Silicone varnishes, various modified silicone varnishes, silicone oils, various modified silicone oils, silane coupling agents, silane coupling agents having functional groups, other organic silicon compounds, organics for the purpose of hydrophobicization, control of charging properties, etc. It is also possible and preferable to treat with a treating agent such as a titanium compound or various treating agents in combination.

To measure the specific surface area, a specific surface area measuring device "Autosorb 1" (manufactured by Yuasa Ionics) was used to adsorb nitrogen gas on the sample surface, and the specific surface area was calculated by the BET multipoint method.

Further, the inorganic fine powder is preferably treated with at least silicone oil in order to maintain a high charge amount and achieve a high transfer rate and good matching with an image forming apparatus.

In the toner according to the present invention, other additives, for example, lubricant powders such as polyfluorinated ethylene powder, zinc stearate powder, and polyvinylidene fluoride powder; Powder, silicon carbide powder, strontium titanate powder and other abrasives; fluidity-imparting agents such as titanium oxide powder and aluminum oxide powder; anti-caking agent, or conductive such as carbon black powder, zinc oxide powder and tin oxide powder A small amount of a property imparting agent, or organic fine particles and inorganic fine particles having opposite polarities can be used as a developability improving agent.

The dry toner of the present invention can be used as it is as a one-component developer or as a two-component developer by mixing with a carrier.

When used as a two-component developer, for example, a magnetic carrier mixed with toner is iron,
It is composed of an element selected from copper, zinc, nickel, cobalt, manganese, chromium and the like in a single or composite ferrite state. The shape of the magnetic carrier used at this time may be spherical, flat, amorphous, or the like, and it is also possible to use one in which the fine structure of the surface state of the magnetic carrier (for example, surface irregularity) is appropriately controlled. I can. Further, a resin-coated carrier whose surface is coated with a resin can also be preferably used. The average particle size of the carrier used is preferably 10-
It is 100 μm, more preferably 20 to 50 μm. Further, when a two-component developer is prepared by mixing these carriers and toner, the toner concentration in the developer is preferably about 2 to 15% by mass.

As a method for producing the dry toner of the present invention, a binder resin, a colorant, a wax component, etc. are melt-kneaded by a pressure kneader or the like, and then the cooled kneaded product is finely pulverized to a desired toner particle size. Further, a pulverization method in which a finely pulverized product is classified to adjust the particle size distribution to obtain a toner; JP-B-36-10231.
JP, JP-A-59-53856 and JP-A-59.
A method for directly producing a toner by using the suspension polymerization method described in JP-A-61842; JP-B-56-13945.
A method for producing a spherical toner by atomizing a melt-kneaded product into the air using a disk or a multi-fluid nozzle described in Japanese Patent Publication No. JP-A No. 2000-187; and a known method such as an emulsion polymerization method typified by a soap-free polymerization method It is possible.

By the way, since the colorant added to the toner particles generally has many hydrophilic functional groups, the granulated particles of the polymerizable monomer composition are polymerized in an aqueous dispersion medium. When forming the toner particles, the particles may migrate toward the interface between the polymerizable monomer composition that is a dispersoid and the aqueous medium, and as a result, reaggregation may occur near the surface of the toner particles. In such a case, not only the charge amount and charge speed of the obtained toner particles but also the heat fixing and the like are adversely affected, and the matching with the image forming apparatus is hindered.

On the other hand, the inventors of the present invention appropriately suspended the colorant as described above within the range of the desired blending amount, and previously dispersed / mixed it with a part of the polymerizable monomer composition and then suspended it. It has been found that the colorants can be fixed in good condition inside the toner particles by producing the toner by the turbid polymerization method. For example, in the case of toner particles of a magenta developer, a quinacridone colorant and a monoazo colorant are predispersed / mixed with a part of a polymerizable monomer composition to prepare a pigment dispersion composition, which is used as the remaining polymerizable compound. By providing for the production of a toner by a suspension polymerization method together with the monomer composition, the re-aggregation of the quinacridone colorant or the monoazo colorant alone is prevented, and the quinacridone colorant is contained in the toner particles. The monoazo colorant can be encapsulated while maintaining the interaction, and the resulting toner particles can be provided with desirable charging characteristics, color developability and fixability. Also, matching with the image forming apparatus is significantly improved. The effects as described above are further improved by the coexistence of the charge control agent and the polar resin as described above during the production of the pigment dispersion composition.

In the toner manufacturing method according to the present invention,
As the dispersant used when preparing the aqueous dispersion medium, known inorganic and organic dispersants can be used. Specifically, as the inorganic dispersant, for example,
Tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, magnesium carbonate, calcium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina Etc. As the organic dispersant, for example, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose,
Starch or the like can be used.

It is also possible to use commercially available nonionic, anionic and cationic surfactants. For example, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, calcium oleate and the like can be used.

In the method for producing a toner according to the present invention, an inorganic sparingly water-soluble dispersant is preferable, and a sparingly water-soluble inorganic dispersant which is soluble in an acid may be used. Further, in the present invention, when a water-based dispersion medium is prepared using a poorly water-soluble inorganic dispersant, these dispersants are used in an amount of 0.2 to 2. 0
It is preferable to use it in such a proportion that it becomes part by mass. Further, in the present invention, it is preferable to prepare an aqueous dispersion medium using 300 to 3,000 parts by mass of water with respect to 100 parts by mass of the polymerizable monomer composition.

In the present invention, when preparing an aqueous dispersion medium in which the above-described sparingly water-soluble inorganic dispersant is dispersed, a commercially available dispersant may be used as it is, but a fine uniform particle size may be used. In order to obtain the dispersant particles having the above, the poorly water-soluble inorganic dispersant as described above may be prepared in a liquid medium such as water under high speed stirring. For example, when using tricalcium phosphate as a dispersant,
A preferable dispersant can be obtained by mixing an aqueous solution of sodium phosphate and an aqueous solution of calcium chloride under high-speed stirring to form fine particles of tricalcium phosphate.

Next, the polymerizable monomer composition used in the toner production method of the present invention will be described. The polymerizable monomer composition is at least a polymerizable vinyl-based monomer, a quinacridone-based colorant, and a monoazo-based colorant, preferably, in addition to this, a charge control agent, a wax component, and if necessary. It is prepared by dissolving and mixing various additives.

As the polymerizable vinyl-based monomer used at this time, the polymerizable monomers described above are appropriately mixed and used so that the theoretical glass transition temperature (Tg) is 40 to 75 ° C. To be In particular, when Tg is high, when a color toner for forming a full-color image is manufactured, the color mixing property of each color toner at the time of fixing is lowered, the color reproducibility is poor, and the transparency of the OHP image is lowered. It is not preferable because

Specific examples of the polymerization initiator used in the toner production method of the present invention include 2,2′-azobis- (2,4-dimethylvaleronitrile) and 2,2 ′.
-Azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-
Azo- or diazo-type polymerization initiators such as azobis-4-methoxy-2,4-dimethylvaleronitrile and azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichloro Peroxide type polymerization initiators such as benzoyl peroxide and lauroyl peroxide are used. The amount of these polymerization initiators used varies depending on the intended degree of polymerization, but is generally 5 to 20 parts by mass with respect to 100 parts by mass of the polymerizable vinyl-based monomer. Although the type of the polymerization initiator varies slightly depending on the polymerization method, it may be used alone or in combination with reference to the 10 hour half-life temperature.

In the polymerizable monomer composition, known crosslinking agents, chain transfer agents, polymerization inhibitors and the like may be further added to control the degree of polymerization. These additives can be added to the polymerizable monomer composition in advance, or can be appropriately added during the polymerization reaction, if necessary.

The image forming method of the present invention is an image forming method for forming a full-color image by sequentially repeating a plurality of image forming steps. After the image formation is started, the final image forming step achieves full-color image formation by forming an image with a black developer, and each image forming step includes
At least (a) a charging step of charging an image carrier for carrying an electrostatic latent image; (b) an exposure step of forming an electrostatic latent image on the charged image carrier by image exposure; (c) static A developing step of developing the latent electrostatic image with the toner carried on the surface of the toner carrier to form a toner image; (d) the toner image formed on the surface of the image carrier via an intermediate transfer member. Or a transfer step of transferring to a transfer material without intervention; and (e) a cleaning step of cleaning and removing the toner remaining on the surface of the image carrier after the transfer step,
The image forming apparatus has a fixing step in which the above steps (a) to (e) are repeated using the cleaned image carrier and the toner image transferred onto the transfer material is heated and fixed to form a fixed image. .

Next, the image forming method of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is an example in which the image forming method of the present invention is applied to a full-color image forming apparatus. A plurality of image forming portions form toner images of different colors, respectively, and these are sequentially formed on the same transfer material. FIG. 6 is a schematic explanatory diagram showing a full-color image forming apparatus using an image forming method for forming a multicolor image by superposing and transferring.

The main body of the full-color image forming apparatus includes a first image forming unit Pa, a second image forming unit Pb,
A third image forming apparatus unit Pc and a fourth image forming apparatus unit Pd are provided side by side, and toner images of different colors are developed in the respective image forming apparatus units and then conveyed by a transfer material conveying belt. A full-color image is obtained by transferring the image onto a transfer material and further fixing it under heat and pressure.

Regarding the structure of each image forming unit provided in the image forming apparatus, the first image forming unit Pa
Will be described as an example.

The first image forming unit Pa is provided with a photosensitive drum 19a having a diameter of 24 mmφ as an electrostatic latent image carrier, and the photosensitive drum 19a rotates and moves in the direction of arrow a.

As a charging means, a primary charging roller 16a having a diameter of 12 mm is arranged so as to contact the surface of the photosensitive drum 19a. A laser beam 1 is emitted from the exposure device 13a according to an image signal to the photosensitive drum 19a that is uniformly primary-charged by the primary charging roller 16a.
An electrostatic latent image is formed by 4a.

The developing device 17a has developing means for developing the electrostatic latent image formed on the surface of the photosensitive drum 19a to form a toner image, and the toner of the first color and the toner. Developing roller 15a having a diameter of 18 mm and carrying a thin layer of toner on the surface of the photosensitive drum 19 via the thin layer of toner.
The toner image of the first color is developed so as to be in contact with a.

The toner image of the first color developed on the photosensitive drum 19a is transferred onto the surface of the transfer material (recording material) S conveyed by the belt-shaped transfer material carrier 20, and the transfer blade 11a as a transfer means. Transcribed by The transfer blade 11a is in contact with the back surface of the transfer material carrier 20 and can apply a transfer bias by the bias applying means 12a.

After the transfer, the cleaning device 18a removes the residual toner on the surface of the photosensitive drum 19a, and the surface of the photosensitive drum 19a is used for the subsequent electrostatic latent image formation.

The image forming apparatus according to the present invention has the same structure as the first image forming unit Pa, but the second image forming apparatus unit P in which the color of the toner held in the developing device is different.
b, a third image forming apparatus unit Pc, and a fourth image forming apparatus unit Pd are provided side by side. For example, the first image forming apparatus unit Pa has yellow toner, the second image forming apparatus unit Pb has magenta toner, the third image forming apparatus unit Pc has cyan toner, and the fourth image forming apparatus unit Pd. The black toner is used for each color toner image, and the toner images of the respective colors are sequentially transferred onto the transfer material at the transfer portion of each image forming apparatus unit. At this time, during this process, the transfer material is moved while registration is performed, the toners of respective colors are superposed on the same transfer material, and when completed, the separation charging device 21 separates the transfer material S from the transfer material carrier 20. It is sent to the fixing device 23 by a carrying means such as a carrying belt, and a desired full-color image is obtained by a single fixing.

In FIG. 1, the transfer material carrier 20 is an endless belt-shaped member, and this belt member is moved by the drive roller 80 in the direction of arrow e as the image formation proceeds. A belt driven roller 81, a belt neutralization device 82, and a belt cleaning device 83 are arranged around the transfer material carrier 20, and the pair of registration rollers 2 are provided.
Reference numeral 4 is provided to convey the transfer material S in the transfer material holder to the transfer material carrier.

In the image forming apparatus as described above, as the transfer means, a roller-shaped transfer roller may be used instead of the transfer blade contacting the back side of the transfer material carrier.
It is also possible to use a non-contact charging means such as a corona charger.

Further, as a conveying means for conveying the transfer material, a conveying belt using a mesh of tetron fiber, a polyethylene terephthalate resin, a polyimide resin, and a urethane resin are used from the viewpoint of ease of processing and durability. Although a transport belt using a thin dielectric sheet as described above is used, a configuration having a drum type transport means may be used.

In the image forming apparatus as described above, since the toner images of the respective colors are sequentially transferred onto the same transfer material in the transfer section of each image forming apparatus unit, the toner image transferred first is the toner transferred later. It is in contact with the photosensitive drum carrying the image. At this time, if there is an unstable charged state among the toner particles forming the toner image on the transfer material that has been transferred first, it is so-called pulled back to the photosensitive drum to which the transfer is subsequently performed. This causes a "retransfer phenomenon", which is a starting point for degrading image quality. However, in the present invention, by specifying the type and content of the colorant in each toner particle of the chromatic color developer, it is possible to prevent the image defect as described above.

The color image forming developer kit of the present invention is a primary transfer step for transferring the toner image formed by developing the electrostatic latent image formed on the electrostatic latent image carrier to the intermediate transfer body. , And an image forming apparatus having a secondary transfer step of transferring the toner image transferred to the intermediate transfer member to a transfer material.

The heating / pressurizing means used in the image forming method of the present invention is a means for forming a fixed image by heating / pressurizing and fixing the toner image on the transfer material.
(I) a rotary heating member having at least a heating body and a rotary pressing member forming a nip portion by mutually pressure-contacting the rotary heating member, and (ii) applied on a contact surface of the transfer material with the toner image. Consumption of offset prevention liquid is 0-0.0
The transfer material is set to 25 mg / cm ² (based on the unit area of the transfer material), and (iii) the toner image on the transfer material is held by the rotary heating member and the rotary pressure member while nipping and transferring the transfer material at the nip portion. It is heated and pressurized.

The rotary heating member which constitutes a part of the heating and fixing means is for applying heat for fixing the toner image on the transfer material, and (i) is a heating and pressing method of a heat roller system. A cylindrical member having a heating body for internally applying heat to the toner image, and (ii) a support for applying heat to the toner image internally, which is used as a film type heating and pressurizing means. A cylindrical heat-resistant endless film member having a heating body fixedly supported on the body and driven to move while being pressed against the heating body, (iii) used in an electromagnetic induction type heating and pressing means, and having a magnetic field inside. It is a cylindrical heat-resistant endless film-like member having a generating unit and having a heat generating layer for applying heat to the toner image by electromagnetically generating heat by the action of the magnetic field generating unit.

Further, the rotary pressing member is a member for forming a nip portion by making pressure contact with the rotary heating member, and heating and pressing the toner image on the transfer material while nipping and transferring the transfer material at the nip portion. is there.

In the image forming method of the present invention, the consumption amount of the offset preventing liquid applied to the contact surface of the transfer material with the toner image is 0 to 0.025 mg / cm ² (based on the unit area of the transfer material). More preferably, the offset prevention liquid is set to a state where it is not applied at all. This can solve the problems caused by the offset preventing liquid as described above, and by using the developer as described above, the performance of the heating / pressurizing unit can be maintained for a long period of time to form an excellent fixed image. It becomes possible to obtain.

For the measurement of the consumption amount of the offset preventing liquid, general office recycled paper (blending rate of recycled pulp ≧ 70%) corresponding to the maximum paper passing area of the heating / pressurizing means in question was used, and the recycled paper was recycled. It is defined as a value (mg / cm ² ) divided by the total area (cm ² ) of recycled paper using the weight (mg) of the offset preventing liquid consumed when 100 sheets of paper are passed.

Toner particles exhibiting the above-mentioned shape distribution generally tend to have a small specific surface area and volume. For example, when a pigment composition exhibiting needle-like crystals such as a quinacridone colorant is added, it is needle-shaped. If the tips of the crystals are unevenly distributed in the vicinity of the surface of the toner particles, or if it is extremely large, the re-aggregates are arranged along the surface of the particles, which adversely affects the surface resistance and charging characteristics of the toner particles. Not only the developing characteristics, the transfer characteristics, and the matching with the image forming apparatus are deteriorated, but also for the heating and pressing fixing means,
In particular, the effect is seen when using a heating / pressurizing fixing unit in which the amount of the offset preventing liquid applied is small on the contact surface with the toner image on the transfer material, and a large number of printouts are continuously repeated or the transfer material is printed on the transfer material. When fixing a color image with a plurality of toner layers, when the fixing device suddenly drops in temperature, there are several fixing defects with a diameter of about 2 mm called "image peeling" on the surface of the fixed image. Occurs over. At this time, since the minute pieces of the peeled-off fixed image are offset also in the heating and pressing fixing means, a serious problem occurs in the heating and pressing fixing means. In particular, it becomes apparent when the heating and pressing means as described above is used.

However, in the toner particles according to the present invention, the dispersion state in the toner particles can be improved and reaggregation of the colorant can be suppressed by specifying the kind and content of the colorant. It is possible to prevent problems such as

[0139]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited thereto.

(Toner Production Example 1) 700 g of ion-exchanged water and 0.1 g of deionized water were placed in a 2-liter four-necked flask equipped with a high-speed stirrer CLEARMIX (manufactured by M Technique Co., Ltd.).
Introduce 800 g of mol / L-Na ₃ PO ₄ aqueous solution, set the rotation speed of the high-speed stirring device to 15000 rpm, and 60 ° C.
It was heated to. 1.0 mol / L-CaCl ₂ here
70 parts by weight of an aqueous solution is added, and a minute, slightly water-soluble dispersant Ca
_An aqueous dispersion medium containing ₃ (PO ₄ ) ₂ was prepared. Further, it was re-prepared with dilute hydrochloric acid so that the pH of the aqueous dispersion medium became 5.5.

On the other hand, as dispersoids: 77 parts by mass of styrene monomer 23 parts by mass of 2-ethylhexyl acrylate monomer 0.2 parts by mass of divinylbenzene monomer 3 parts by mass of condensed azo pigment (C. I. Pigment Yellow 93) -Yellow dye 3 parts by mass (CI Solvent Yellow 162) -Polyester resin 5 parts by mass (peak molecular weight = 4500, acid value = 25 mgKOH / g) -Di-tert-butylsalicylic acid 1 part by mass Ester wax (melting point = 65 ° C.) A mixture of 15 parts by mass was dispersed for 3 hours using an attritor (manufactured by Mitsui Kinzoku Co., Ltd.), and then 2,2′-azobis (2,4-dimethylvaleronitrile) 3 parts by mass. Parts were added to prepare a polymerizable monomer composition.

Then, the polymerizable monomer is added to the aqueous dispersion medium.
The body composition is added and the internal temperature is 65 ° C. ₂Fast in the atmosphere
While maintaining the rotation speed of the stirring device at 15000 rpm, 1
The mixture was stirred for 0 minute to granulate the polymerizable monomer composition. That
After that, change the stirring device to one equipped with paddle stirring blades,
While maintaining the same temperature while stirring at 200 rpm,
When the polymerization conversion rate of the nil monomer reached 95%
Aqueous dispersion by adding 0.1 mol / L NaOH aqueous solution
The pH of the medium was changed to 10. Furthermore, the reaction temperature was raised to 85 ° C.
When the temperature rises and the polymerization conversion rate becomes almost 100%,
The combined reaction was completed.

After completion of the polymerization, residual monomers were distilled off under heating and reduced pressure, and after cooling, dilute hydrochloric acid was added to dissolve the hardly water-soluble dispersant. After repeating water washing several times,
Using a conical ribbon dryer (manufactured by Okawara Seisakusho), a drying treatment was performed to obtain polymer particles (Y-1).

100 parts by mass of the polymer particles (Y-1) and oil-treated silica fine powder (BET specific surface area = 200 m)
^{2 /} g) 1.2 parts by mass and hydrophobized titanium oxide fine powder (BET method specific surface area = 50 m ^{2 /} g) 0.3 parts by mass are dry-mixed by a Henschel mixer (manufactured by Mitsui Kinzoku Co., Ltd.) to obtain toner (Y -1).

The circle-equivalent number average diameter of the toner (Y-1) was 5.2 μm, the average circularity in the circularity frequency distribution was 0.983, and the circularity standard deviation was 0.019. In addition, the peak molecular weight in THF of the binder resin component constituting the toner particles, which is soluble in THF, is 18,000.
The insoluble content was 20% by mass.

(Toner Production Examples 2 and 3) The amounts of the condensed azo pigment used as a colorant, the yellow dye, and the divinylbenzene monomer were changed, and the set temperature during the polymerization reaction during the production of the toner, After obtaining polymer particles (Y-2) and (Y-3) in the same manner as in the Production Example 1 of the toner, except that the pH of the aqueous dispersion medium and the polymerization conversion rate at the time of switching the pH are changed, the toner is obtained. (Y-2) and (Y-3) were prepared.

(Toner Production Example 4) The following mixture was dispersed for 4 hours using an attritor (manufactured by Mitsui Kinzoku Co., Ltd.) to prepare a pigment dispersion composition. Quinacridone colorant 4 parts by mass (solid solution pigment of CI Pigment Red 122 and CI Pigment Violet 19) Monoazo colorant 4 parts by mass (CI pigment red 150) Body 43 parts by mass Charge control agent (Al compound of dialkylsalicylic acid) 1 part by mass Polyester resin 5 parts by mass (Peak molecular weight = 5500, Acid value = 30 mgKOH / g)

In a separate container, 40 parts by mass of styrene monomer, 17 parts by mass of n-butyl acrylate monomer, 0.2 parts by mass of divinylbenzene monomer, and ester wax (melting point = 60 ° C.) 7 57 parts by mass of the pigment dispersion composition was added to a mixture of parts by mass, and the mixture was dispersed and dissolved while heating at 60 ° C.
3 parts by mass of 2-azobis (2,4-dimethylvaleronitrile) was added to prepare a polymerizable monomer composition as a dispersoid.

Polymer particles (M-M) were produced in the same manner as in the toner production example 1 except that the temperature set during the polymerization reaction during the toner production, the pH of the aqueous dispersion medium, and the polymerization conversion rate during the pH change were changed. After obtaining 1), toner (M-1)
Was prepared.

(Toner Production Examples 5 to 7) The addition amount of the quinacridone pigment and the monoazo pigment used as colorants and the divinylbenzene monomer was changed, and the set temperature during the polymerization reaction during the toner production, P of aqueous dispersion medium
H and polymer particles (M
-2) to (M-4), and then toners (M-2) to (M
-4) was prepared.

(Toner Production Examples 8 to 10) As a phthalocyanine colorant, C.I. I. Pigment Blue
The same procedure as in Toner Production Example 1 except that 15: 3 was used, and the set temperature during the polymerization reaction during the toner production, the pH of the aqueous dispersion medium, and the polymerization conversion rate during the pH change were changed. After obtaining particles (C-1) to (C-3), toners (C-1) to (C-3) were prepared.

(Manufacturing Example 11 of Toner) 6 parts by mass of carbon black (average particle size = 35 nm) as a colorant and 2 parts by mass of a monoazo Fe complex as a charge control agent were used, and the setting at the time of a polymerization reaction at the time of manufacturing a toner was set. After the polymer particles (Bk-1) were obtained in the same manner as in the toner production example 1 except that the temperature, the pH of the aqueous dispersion medium, and the polymerization conversion rate when the pH was changed, the toner (Bk-1) was obtained. ) Was prepared.

(Production Examples 1 to 3 of Comparative Toner) The type and addition amount of the colorant were changed, the set temperature during the polymerization reaction during the toner production, the pH of the aqueous dispersion medium, and the pH were adjusted.
Except for changing the polymerization conversion rate at the time of switching, polymer particles (y-1), (m-
1) and (m-2), toners (y-1) and (m-
1) and (m-2) were prepared.

(Toner Production Examples 12 to 15) The polymer particles (Y-1), (M-1), (C-1), and (Bk).
-1) 1.0 part by mass of hydrophobized titanium oxide fine powder (BET specific surface area = 270 m ^{2 /} g) and 100 parts by mass of oil-treated silica fine powder (BET specific surface area = 50 m)
^{2 /} g) 0.5 part by mass of toner (Y-1b) and (M-1) obtained by dry mixing with a Henschel mixer (manufactured by Mitsui Kinzoku).
b), (C-1b), and (Bk-1b), the resin coat carrier 92 is added to 8 parts by mass of these toners.
By mass dry mixing the parts by weight with a Nauter mixer (manufactured by Hosokawa Micron Co., Ltd.), two-component developer (Y-1b), (M-
1b), (C-1b), and (Bk-1b).

(Preparation Examples 4 to 5 of Comparative Toner) A two-component developer (y) was prepared in the same manner as in Preparation Example 12 of the toner except that the polymer particles (y-1) and (m-1) were used. -1
b) and (m-1b) were prepared.

Tables 1 and 2 collectively show colorant formulations used in the above-mentioned toner production examples and comparative toner production examples, and various properties of the obtained toners.

[0157]

[Table 1]

[0158]

[Table 2]

<Embodiment 1> Toner images of different colors are formed in a plurality of image forming portions shown in FIG. 1, and these toner images are successively superimposed and transferred onto the same transfer material to form a multicolor image. The first image forming apparatus unit Pa, the second image forming unit Pb, and the third image forming apparatus unit P are used by using a full-color image forming apparatus using the image forming method for forming.
c, and the toners (Y-1), (M-1) obtained in the toner manufacturing example above in the fourth image forming apparatus unit Pd,
Using (C-1) and (Bk-1), and using a test pattern prepared so that the printing ratio of each color toner is 4 area% under normal temperature and normal humidity environment while sequentially replenishing as necessary. , As a transfer material, "Recycled Paper EN
-100 "(recycled pulp content = 100%),
1 at a printout speed of 16 sheets / minute (A4 size paper)
A printout test was performed for 10,000 sheets.

In the fixing device, a heat roller type heating / pressurizing means without a separating claw or an offset preventing liquid applying mechanism is used. As the heating roller, one obtained by subjecting an aluminum cylindrical core metal to a primer treatment, and then providing an elastic layer of dimethyl silicone rubber and a surface layer of a PFA tube having a thickness of 50 μm via the primer layer was used. The pressure roller used was one in which an elastic layer of dimethylsilicone rubber was provided after a SUS cored bar was treated with a primer, and a surface layer was provided with a PFA tube having a thickness of 50 μm via the primer layer. In addition, a halogen heater is provided as a heating element inside the cylindrical core of the heating roller so that the surface temperature of the fixing roller becomes 180 ° C. when the heating and pressurizing means is activated. The pressure roller has 245N (25k
The contact pressure of gf) was applied so that a nip portion having a width of 3 mm was formed.

The obtained printout image was excellent in color reproducibility, fine line reproducibility and image light fastness, and the printout test was completed while maintaining the color reproducibility in the initial state.

Further, the print-out image was free from image peeling and the like, and after the print-out test was completed, the roller surface of the fixing device was visually evaluated to find that there was no problem such as toner adhesion and that the image forming device was It turned out that it is also excellent in matching.

The results of these evaluations are summarized in Table 3.

<Examples 2 to 5> Each image forming apparatus unit was sequentially filled with the chromatic color toner obtained in the above toner production example, and the toner was printed in the same manner as in Example 1 while successively replenishing as necessary. When an out test was conducted, good results were obtained.

The results of these evaluations are summarized in Table 3.

Comparative Example 1 Similar to Example 1, each image forming apparatus unit was sequentially filled with the comparative chromatic color toner obtained in the above comparative toner manufacturing example, and replenished successively as needed. I did a printout test with
Color reproducibility, fine line reproducibility, and image light fastness were not at sufficient levels.

Further, problems such as image peeling occurred in the printout image, and a phenomenon such as the printout image being wrapped around the roller surface of the fixing device was observed during the printout test.

The results of these evaluations are summarized in Table 3.

<Comparative Examples 2 and 3> In the same manner as in Example 1, each image forming apparatus unit was filled with the comparative toner sequentially obtained in the above comparative toner manufacturing example, and successively replenished as needed. When a printout test was conducted, color reproducibility, fine line reproducibility, image light resistance, image peeling, matching with a fixing device, etc. were not at a sufficient level.

The results of these evaluations are summarized in Table 3.

<Embodiment 6> The first image forming apparatus unit Pa, the second image forming apparatus Pb, the third image forming apparatus unit Pc, and the fourth image forming apparatus unit Pd.
Of the two-component developers (Y-1b) and (M-1) obtained in the above toner production examples.
b), (C-1b) and (Bk-1b), and toners (Y-1b), (M-1b), (C-1) as required.
Example 1 while sequentially supplying b) and (Bk-1b).
A printout test was conducted in the same manner as in.

The obtained printout image was excellent in color reproducibility, fine line reproducibility and image light fastness, and the printout test was completed while maintaining the color reproducibility in the initial state.

Further, the print-out image was free from image peeling and the like, and after the print-out test was completed, the roller surface of the fixing device was visually evaluated to find that there was no problem such as toner adhesion and that the image forming device was It turned out that it is also excellent in matching.

The results of these evaluations are summarized in Table 3.

<Comparative Example 4> The first image forming apparatus unit Pa, the second image forming apparatus Pb, the third image forming apparatus unit Pc, and the fourth image forming apparatus unit Pd.
Each of which was modified for two-component contact development, and the two-component developers (y-1b), (m-1b), (C-1b) obtained in the above-mentioned toner production examples and comparative toner production examples And (Bk
-1b), and optionally toner (y-1b),
When a printout test was conducted in the same manner as in Example 6 while successively replenishing (m-1b), (C-1b) and (Bk-1b), color reproducibility, fine line reproducibility and image light fastness were confirmed. The image peeling and matching with the fixing device were not at a sufficient level.

The results of these evaluations are summarized in Table 3.

[0177]

[Table 3]

The evaluation items described in the examples and comparative examples and the evaluation criteria will be described.

[Printout Test] <1> Color Space Volume on Plain Paper A full-color image obtained on normal plain paper for copiers (75 g / m ² ) was used as “Spectrophotometer SP68”.
(Made by X-Rite Co., Ltd.) to measure lightness L ^{* of} the L ^* a ^* b ^* color system standardized by the International Commission on Illumination (CIE), a ^* representing the degree of red to green, and A color space solid determined by b ^* representing the degree of yellow to blue was determined, and the volume of the color space solid was determined. The larger the volume (numerical value) of the color space solid, the better the color reproducibility. A: 2.5 million or more B: 2 million or more, less than 2.5 million C: 1.5 million or more, less than 2 million D: less than 1.5 million

<2> Fine Line Reproducibility This is an evaluation relating to the image quality and gradation of the graphical image, and the fine line reproducibility of the printout image as shown in FIG. 2 was evaluated. A: Good fine line reproducibility B: Minor fine line width variation C: Conspicuous thin line fineness and scattering D: Fine line rupture observed in places, poor reproducibility

<3> Color Reproducibility of Projected Image The full-color image obtained on the transparency film is transferred to the overhead projector “OHP 955”.
0 "(manufactured by 3M) to form a transparent image, and the secondary image portion of the projected image obtained by projecting the transparent image on a white screen (red: yellow 50% / magenta 50%, green: cyan 50% / yellow). 50%, blue: magenta 50% / cyan 50%) is visually evaluated, and the color is measured with a spectral radiance meter (manufactured by Photo Research Co.) to obtain a color space solid represented by an L ^* a ^* b ^* color system. Was determined and the volume of the color space solid was determined.

Visual evaluation of secondary color part A: Vivid color reproducibility of secondary colors (red and blue) and excellent transparency B: Excellent color reproducibility and transparency of primary color, but 2 Slightly inferior in color reproducibility of primary color: Slightly inferior in color reproducibility and transparency of primary color D: Inferior in color reproducibility of primary color, causing dullness

Volume of color space solid A: 2.5 million or more B: 2 million or more, less than 2.5 million C: 1.5 million or more, less than 2 million D: less than 1.5 million

<4> Image Peeling A solid image was formed on a slightly thick transfer paper (105 g / m ² , A4 size) so that the toner amount was about 0.8 mg / cm ² , and the obtained image surface The occurrence of image peeling was visually evaluated. The fewer the image peeling points,
The occurrence has been suppressed. A: Not generated B: 1 or more and 5 or less C: 6 or more and 10 or less D: 11 or more (or image peeling of 2 mm or more in diameter occurs)

<5> Image resistance to light A solid image having a toner amount of about 0.6 mg / cm ² on a transfer paper was prepared, and an ultraviolet auto fade meter "FAL-AU" (Suga Test Instruments Co., Ltd.) using a carbon arc lamp as a light source was used. Manufactured by K.K.) and evaluated according to “JIS K 7102”. The maximum irradiation time was set to 240 hours, the maintenance ratio of the image density before and after the light irradiation was calculated, and the light resistance of the image was evaluated. The closer the image density maintenance ratio (%) is to 100%, the better the image light resistance. A: 90% or more B: 80% or more, less than 90% C: 65% or more, less than 80% D: less than 65%

[Evaluation of Matching with Fixing Device] After completion of the printout test, the state of sticking of the residual toner on the heating roller and the influence on the printout image were visually evaluated. A: No toner sticking B: Contamination due to paper dust and toner sticking to the edges were observed, but the effect on the fixed image was minor C: Contamination due to paper dust and toner sticking to the edges Although there is slight toner stain on the back side of the printout image due to sticking, there is almost no effect on the fixed image. D: Effect of sticking toner on the fixed image and winding of the printout image during the printout test. Occurs

[0187]

As described above, according to the present invention,
An image forming apparatus using an image forming method for forming a multicolor image by forming toner images of different colors in a plurality of image forming sections and sequentially superposing and transferring the toner images on the same transfer material, By using a color image-forming developer kit consisting of a chromatic color developer and a black developer with a specified colorant, high-definition and high-resolution full-color image formation that achieves a wide range of color reproduction is achieved, and sufficient Image light resistance is achieved, and even when applied to a fixing device that does not use an offset prevention liquid, it is possible to prevent toner from remaining on the surface of the fixing member such as the fixing roller of the fixing device. Therefore, good color reproduction can be stably obtained even when a large number of sheets are printed out.

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram of a full-color image forming apparatus used in an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a line image for evaluating the reproducibility of a fine line.

[Explanation of symbols]

15a Developing roller 17a, 17b, 17c, 17d Developing device 19a, 19b, 19c, 19d Photosensitive drum 20 Transfer material carrier 23 Fixer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/01 G03G 15/20 102 104 104 20/20 9/08 361 104 325 (72) Inventor Emi Tosaka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masanori Ito 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Koichi Tomiyama Ota, Tokyo 3-30-2 Maruko Shimoshita F term in Canon Inc. (reference) 2H005 AA01 AA06 AA08 AA21 CA04 CA14 CA21 CB13 EA05 EA06 EA07 EA10 2H030 AB02 AD01 AD04 AD16 BB63 2H033 AA11 BA46 BA58 BB01 BB28

Claims (12)

[Claims] 1. A color image forming developer kit comprising at least three chromatic color developers, a yellow developer, a magenta developer, and a cyan developer, wherein each of the chromatic developers is A toner having at least a binder resin, a colorant and a wax component and an inorganic fine powder, and as a colorant in the toner particle, a. The yellow toner particles in the yellow developer include the condensed azo pigment represented by the following structural formula (1) and C.I. I. Sol
Vent Yellow 9, the same 17, the same 24, the same 3
1, 35, 58, 93, 100, 102, 103, 105, 112, 162, 163,
C. I. Dispers Yellow 42, 6
No. 4, No. 82, No. 160, No. 201, No. 224, each containing a yellow dye (each according to the name described in the fourth edition of the color index), and the total content is 1 to 20% by mass. And the mass ratio of the contents is condensed azo pigment: monoazo dye = 25: 75 to 75:25, and b. The magenta toner particles in the magenta developer contain a quinacridone pigment represented by the following structural formula (2) and a monoazo pigment represented by the following structural formula (3), and the total content thereof is 1 to 20% by mass. , The mass ratio of the content is quinacridone pigment: monoazo pigment = 25: 75 to 75:25
And, [X ₁ and X ₂ represent a hydrogen atom or a substituent selected from an alkyl group, an alkoxy group and a halogen group. ] [Chemical 3] c. The cyan toner particles in the cyan developer contain a phthalocyanine-based pigment, and the content thereof is 1 to 10% by mass, which is a developer kit for color image formation. 2. The developer kit for forming a color image according to claim 1, comprising at least three color chromatic developers of a yellow developer, a magenta developer and a cyan developer and a black developer. 3. The toner particles in the developer have a circle-equivalent number average diameter D1 (μ) in a number-based circle-equivalent diameter-circularity scattergram measured by a flow-type particle image measuring device.
m) is 2 to 10 μm, and the average circularity is 0.950 to 0.9.
95, the circularity standard deviation is less than 0.040, the main component of the binder resin is a styrene-acrylic resin, and the gel permeation chromatography of the soluble portion of tetrahydrofuran (THF) of the binder resin. Graphography (GP
C) has a peak molecular weight of 5,000 to 30,000 and THF
The color image forming developer kit according to claim 1 or 2, wherein the insoluble content is 5 to 35% by mass. 4. A condensed azo pigment used for toner particles in a yellow developer is C.I. I. Pigment Ye
low 93, same 94, same 95, same 128, same 166
Which is selected from the group consisting of C.I. I. Solvent Yellow 93, ibid 105, ibid 112, ibid 162, ibid 163, C.I. I. Di
4. The color image according to claim 1, wherein the color image is any one selected from the group consisting of spers Yellow 42, 64, 160, and 201 (according to the names described in Color Index Fourth Edition). Forming developer kit. 5. A quinacridone pigment used for toner particles in a magenta developer is C.I. I. Pigment
Red 122, 202, C.I. I. Pigment
Any one selected from the group of Violet 19 and / or solid solution pigments thereof, and the monoazo pigment is C.I. I. Pigment Red 5, 3
1, the same 146, the same 147, the same 150, the same 176, the same 18
4. The color image-forming development as claimed in claim 1, which is selected from the group consisting of No. 4, No. 185, and No. 269 (each according to the name described in Color Index Fourth Edition). Agent kit. 6. A phthalocyanine pigment used for toner particles in a cyan developer is C.I. I. Pigment
Blue 15, ibid 15: 1, ibid 15: 2, ibid 15:
4. The color image forming apparatus according to claim 1, wherein the color image forming agent is any one selected from the group consisting of No. 3, No. 15: 4, No. 16 and No. 16 (each according to the name described in Color Index Fourth Edition). Developer kit. 7. An image forming method for forming a full-color image by sequentially repeating a plurality of image forming steps, wherein a final image forming is performed after the image forming by the chromatic color developer is started in the first image forming step and thereafter. Full-color image formation is achieved by forming an image with a black developer by the step, and each image forming step comprises at least (a) a charging step of charging an image carrier for carrying an electrostatic latent image; ) An exposure step of forming an electrostatic latent image on the charged image carrier by imagewise exposure; (c) developing the electrostatic latent image with toner carried on the surface of the toner carrier to form a toner image Developing step; (d) transfer step of transferring the toner image formed on the surface of the image bearing member to a transfer material with or without an intermediate transfer member; and (e) A cleaning step of cleaning and removing the toner remaining on the surface of the image bearing member after the transferring step, and repeating the steps (a) to (e) using the cleaned image bearing member, and transferring The toner has a fixing step of heating and fixing the toner image transferred onto the material to form a fixed image. The chromatic color developer is a toner particle containing at least a binder resin, a colorant and a wax component and an inorganic material. A yellow developer, a magenta developer, and a cyan developer containing fine powder, and as a colorant in the toner particles, a. The yellow toner particles in the yellow developer include the condensed azo pigment represented by the following structural formula (1) and C.I. I. Sol
Vent Yellow 9, the same 17, the same 24, the same 3
1, 35, 58, 93, 100, 102, 103, 105, 112, 162, 163,
C. I. Dispers Yellow 42, 6
No. 4, No. 82, No. 160, No. 201, No. 224, each containing a yellow dye (each according to the name described in the fourth edition of the color index), and the total content is 1 to 20% by mass. And the mass ratio of the contents is condensed azo pigment: monoazo dye = 25: 75 to 75:25, and b. The magenta toner particles in the magenta developer contain a quinacridone pigment represented by the following structural formula (2) and a monoazo pigment represented by the following structural formula (3), and the total content thereof is 1 to 20% by mass. , The mass ratio of the content is quinacridone pigment: monoazo pigment = 25: 75 to 75:25
And, [X ₁ and X ₂ represent a hydrogen atom or a substituent selected from an alkyl group, an alkoxy group and a halogen group. ] [Chemical 6] c. The cyan toner particles in the cyan developer contain a phthalocyanine pigment, and the content thereof is 1 to 10% by mass. 8. The toner-containing toner particles in the developer have a circle-equivalent number average diameter D1 (μ) in a number-based circle-equivalent diameter-circularity scattergram measured by a flow-type particle image measuring device.
m) is 2 to 10 μm, and the average circularity is 0.950 to 0.9.
95, the circularity standard deviation is less than 0.040, the main component of the binder resin is a styrene-acrylic resin, and the gel permeation chromatography of the soluble portion of tetrahydrofuran (THF) of the binder resin. Graphography (GP
C) has a peak molecular weight of 5,000 to 30,000 and THF
The image forming method according to claim 7, wherein the insoluble content is 5 to 35% by mass. 9. A condensed azo pigment used for toner particles in a yellow developer is C.I. I. Pigment Ye
low 93, same 94, same 95, same 128, same 166
Which is selected from the group consisting of C.I. I. Solvent Yellow 93, ibid 105, ibid 112, ibid 162, ibid 163, C.I. I. Di
spers Yellow 42, same 64, same 160,
9. The image forming method according to claim 7, wherein the image forming method is any one selected from the group of No. 201 (each is based on a name described in Color Index Fourth Edition). 10. A quinacridone pigment used for toner particles in a magenta developer is C.I. I. Pigment
Red 122, 202, C.I. I. Pigment
Any one selected from the group of Violet 19 and / or solid solution pigments thereof, and the monoazo pigment is C.I. I. Pigment Red 5, 3
1, the same 146, the same 147, the same 150, the same 176, the same 18
9. The image forming method according to claim 7, wherein the image forming method is any one selected from the group of No. 4, No. 185, and No. 269 (each according to the name described in Color Index Fourth Edition). 11. A phthalocyanine-based pigment used for toner particles in a cyan developer is C.I. I. Pigment
Blue 15, ibid 15: 1, ibid 15: 2, ibid 15:
9. The image forming method according to claim 7 or 8, wherein the image forming method is any one selected from the group consisting of 3, 15: 4, and 16 (according to the names described in Color Index Fourth Edition). 12. The heating / pressurizing means includes (i) a rotary heating member having at least a heating body, and a rotary pressing member forming a nip portion by mutually pressure-contacting the rotary heating member, (ii)
The consumption amount of the offset prevention liquid applied to the contact surface of the transfer material with the toner image is 0 to 0.025 mg / cm.
² (standard unit area of transfer material), and (ii
i) The toner image on the transfer material is fixed while being heated and pressed by the rotary heating member and the rotary pressing member while nipping and transferring the transfer material at the nip portion. The image forming method according to any one of 1.