JPH0643724A - Color image forming device - Google Patents

Abstract

PURPOSE:To form a color image having high transmissivity of light without color turbidity, a color image excellent in color reproducibility, and a high quality color image having glossiness. CONSTITUTION:A constitution is adopted so that a thermal sublimated dye and a transparent cross linking resin grain are incorporated in binder resin, to obtain color toner having a transparent region, a color toner image 2 is formed by using, at least, three or more kinds of color toner, and transferred on a transfer body 1 whose surface is provided with a transparent resin layer 1' made of thermoplastic resin, and the color toner image on the transfer body 1 is heated/melted by a belt-like heating member 8a, to be fixed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color image forming method for forming a high quality full color image by an electrophotographic method applied to a color copying machine or a color printer.

[0002]

2. Description of the Related Art In one example of a method for forming a full-color image by electrophotography, for example, B (blue) or G is formed on a photoconductor using an organic or inorganic photoconductive material.
(Green), R (red) and ND if necessary
A color separation light obtained through a filter such as (neutral) is irradiated to form an electrostatic latent image for each color, and the electrostatic latent image for each color is Y (yellow), M (magenta), C ( Cyan) and, if necessary, sequential development with color toner such as BK (black) to form a color toner image for each color. Next, the color toner images of the respective colors are formed on the photoconductor in a superposed manner and then collectively transferred to the transfer body, or each time the color toner images of the respective color are formed on the photoconductor, the transfer body is transferred. Transfer on top and overlay on transfer. Then, the color toner image superposed on the transfer body is heated and fixed by a heating roller and a pressure roller to form a color image.

The color toner used in such an electrophotographic method is composed of particles formed by dispersing and containing a dye or a pigment in a thermoplastic resin, and the average particle size thereof is usually 5 to 20 μm. . In the case of forming a color image with such toner particles, a multilayer toner particle layer is required in order to obtain a sufficient image density of the formed color image.

However, when a color image is formed by a multi-layered toner particle layer, particularly a multi-layered toner particle layer in which pigments are dispersed and contained, the obtained color image has low light transmission and color turbidity occurs. The color reproducibility is inferior. Further, it is difficult to fix a color image obtained by a multi-layered toner particle layer to a sufficiently smooth surface state even if it is melted and fixed by heating, and it has irregularities in the surface vertical direction. Then, such a color image has poor gloss and poor color image quality as compared with general photographs and printing.

In order to improve the image quality of such a color image, from the viewpoint of imparting glossiness, a transparent resin layer is formed on an image supporting base material, and toner particles are heated in the transparent resin layer. Attempts have been made to improve by embedding with a roller (see Japanese Patent Laid-Open No. 63-92965, etc.).

[0006]

However, as a result of intensive studies made by the present inventors, although the above-mentioned technique can provide a color image having a certain degree of gloss, the color image is turbid. It lacks in color and sharpness. In addition, since the heating and fixing method uses only the heating roller, the toner particles are not completely melted and are in the state of a rubber-like elastic body, which is elastically deformed by the pressure of the heating roller to become smooth, but the pressure is released. If this happens, the state will be relieved to the original state, and the surface state will not be the same as that of the contacting heating roller, and the toner particles will be raised. Further, in the separation stage where the heating roller and the toner image are separated, the fused toner has adhesiveness to the heating roller, so that the fixed toner image is pulled up by the heating roller in the direction along the surface of the image and floats up. Will end up.

In order to improve the above-mentioned drawbacks, prevent color turbidity in a color image, and improve glossiness, the amount of developing toner is reduced as much as possible and the protrusion of the toner image on the transfer body surface is suppressed. Preferably. However, on the other hand, when the amount of developing toner is small, it is not possible to secure a sufficient image density, and only a color image having low image density with poor color reproducibility can be obtained.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a color image forming method capable of forming a color image having high light transmittance and no color turbidity. Especially. Another object of the present invention is to provide a color image forming method capable of forming a color image having excellent color reproducibility. Another object of the present invention is to provide a color image forming method capable of forming a high quality color image having gloss.

[0009]

Each of the above objects is to provide a color toner having a transparent region by containing a thermally sublimable dye and transparent crosslinked resin particles in a binder resin, and at least 3 of the color toner is used. A color toner image is formed by using at least one kind, and the color toner image is transferred onto a transfer member having a transparent resin layer made of a thermoplastic resin on the surface,
This can be achieved by a color image forming method characterized in that the color toner image on the transfer member is heated and melted by a belt-shaped heating member to be fixed.

The present invention will be described in detail below. In the present invention, a heat sublimable dye is used as a colorant constituting the color toner, and a transparent resin layer made of a thermoplastic resin is provided on the surface of the transfer member. The transparent resin layer can be dyed by thermal diffusion of the dye, so that the image density can be improved and a color image having a good color tone can be obtained.

Further, the color toner used in the present invention contains transparent crosslinked resin particles and has a transparent region. Therefore, a color image obtained with such a color toner has high light transmittance and no color turbidity,
It has excellent gloss and color reproducibility.

On the other hand, in the present invention, the color toner image on the transfer member is heated and fused by the belt-shaped heating member to be fixed. Therefore, the heating time is longer than that of the fixing method using the heating roller, and the transparent resin layer is dyed sufficiently reliably by the thermal diffusion of the heat sublimable dye. Further, by using the belt-shaped heating member, sufficient fixing is achieved, the protrusion of the color toner image on the transfer member surface is suppressed, the smoothness is improved, and the glossiness of the color image is improved.

The color toner used in the present invention comprises a thermally sublimable dye, transparent crosslinked resin particles, and an additive which is optionally used in a binder resin.

Examples of the binder resin constituting the color toner include styrene-acrylic resin, styrene-butadiene resin, polyester resin and the like.

Examples of the heat sublimable dye dispersedly contained in the binder resin include monoazo dyes exemplified below:
Examples thereof include anthraquinone dyes, naphthoquinone dyes, styryl dyes, naphthol dyes, thiazole dyes, quinophthalone dyes, and pyridone dyes. In addition, in order to obtain the black toner, the dyes may be used in combination. The content is 1 to 10% by weight with respect to the color toner particles.

<Monoazo Dye> A compound represented by the following chemical formula 1.

[0017]

[Chemical 1] (R ¹ and R ² each represent an alkyl group or an alkoxy group having 1 to 4 carbon atoms.)

<Anthraquinone type dye> Chemical formula 2 to chemical formula 4 below
Compound shown by

[0019]

[Chemical 2] (R ³ and R ⁴ each represent an alkyl group having 1 to 4 carbon atoms.)

[0020]

[Chemical 3] (R ⁵ represents an alkylene group which may be substituted with an alkoxyalkyl group or an allyloxyalkyl group.)

[0021]

[Chemical 4] (R ⁶ and R ⁷ each represent an alkyl group having 1 to 4 carbon atoms.)

<Naphthoquinone Dye> A compound represented by the following chemical formula 5.

[0023]

[Chemical 5] (R ⁸ and R ⁹ each represent an alkyl group having 1 to 4 carbon atoms.)

<Styryl dye> A compound represented by the following chemical formula 6

[0025]

[Chemical 6] (R ¹⁰ and R ¹¹ each represent an alkyl group or an allyl group having 1 to 4 carbon atoms, and Z ¹ represents a hydroxy group, a cyano group or a halogen.)

<Naphthol dye> A compound represented by the following chemical formula 7

[0027]

[Chemical 7] (R ¹² represents an alkyl group, an alkoxy group or an allyl group having 1 to 4 carbon atoms, and R ¹³ represents an alkyl group, an alkoxy group, an allyl group, a phenyl group substituted or unsubstituted with a halogen or the like.)

<Thiazole dye> A compound represented by the following chemical formula 8

[0029]

[Chemical 8] (R ¹⁴ , R ¹⁵ and R ¹⁶ each represent an alkyl group, an alkoxy group or an allyl group having 1 to 4 carbon atoms, and Z ² represents a methyl group, an acetylamino group or a formylamino group.)

<Quinophthalone dye> A compound represented by the following chemical formula 9

[0031]

[Chemical 9] (R ¹⁷ represents a phenylene group or a naphthylene group, and Z ³ represents hydrogen or halogen.)

<Pyridone dye> A compound represented by the following chemical formula 10

[0033]

[Chemical 10] (R ¹⁸ represents a phenylene group or a naphthylene group, and Z ⁴ represents an alkylene group.)

The transparent crosslinked resin particles contained in the color toner used in the present invention have an average particle size of 0.0.
It is preferably 1 to 2.0 μm. If the average particle size is too large, the glossiness of the color image obtained is hindered,
On the other hand, if the average particle size is too small, the particles are colored and the transparency is impaired.

The content ratio of such transparent crosslinked resin particles is preferably 5 to 30% by weight based on the color toner particles. If this ratio is too small, it is not possible to sufficiently secure the transparent area of the color toner. On the other hand, if this ratio is too large, the resulting color image will have a low image density and insufficient fixing, resulting in poor smoothness and poor gloss.

The transparent crosslinked resin particles are preferably those having a small heat melting property so as not to be melt-mixed with the binder resin or the heat sublimable dye during the production of the color toner. From such a viewpoint, in order to make the softening point of the transparent crosslinked resin particles higher than the softening point of the binder resin,
A crosslinked structure is introduced into the resin particles. Further, in order to obtain resin particles having a high softening point, it is important to select the constituent monomer components.

The transparent crosslinked resin particles can be obtained by an emulsion polymerization method, but from the viewpoint of improving transparency, it is preferably obtained by an emulsifier-free polymerization method without using an emulsifier. In this emulsifier-free polymerization method, transparent crosslinked resin particles can be easily obtained by using a hydrophilic monomer such as (meth) acrylic acid.

Therefore, specific examples of the monomer used to obtain transparent crosslinked resin particles include (meth) acrylic acid type monomers such as acrylic acid and methacrylic acid, methyl (meth) acrylate, and (meth) acrylic. Ethyl acid,
(Meth) acrylic acid ester-based monomers such as propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and dimethylaminoethyl (meth) acrylate, styrene, α-methylstyrene, Examples thereof include styrene-based monomers such as chlorostyrene and p-methylstyrene. Further, in order to introduce a cross-linked structure, a cross-linkable monomer such as divinylbenzene, diethylene glycol dimethacrylate, triethylene glycol trimethacrylate or the like is used in a proportion of 0.1 to 5.0% by weight based on all monomer components.

Examples of the additives that are used as necessary to compose the color toner include colorless charge control agents, internal additives such as wax, and external additives such as inorganic oxide fine particles. As the colorless charge control agent, a metal complex salt of a monoazo dye, a metal complex with a carboxylic acid compound, a quaternary ammonium salt compound, or the like can be used. As the wax, paraffin wax,
A wax having a melting point of 60 to 160 ° C. such as polyethylene wax or polypropylene wax is used as the binder resin 100.
It can be used within a range not exceeding 10 parts by weight with respect to parts by weight. As the above-mentioned inorganic oxide fine particles, silica, titanium oxide or the like which has been hydrophobized by a silane coupling agent or the like can be added and mixed within a range not exceeding 5% by weight with respect to the toner.

The color toner used in the present invention can be manufactured by applying a conventionally known manufacturing method. Specifically, it is manufactured by kneading, pulverizing, and classifying the above toner constituent components.

The color toner used in the present invention may be mixed with a magnetic carrier to form a two-component color developer, which improves fluidity, triboelectric charging property, developing property, image reproducibility and the like. Can be planned. As the magnetic carrier, iron, ferrite, magnetic particles such as magnetite, or magnetic particles obtained by coating these magnetic particles with styrene-acrylic resin, silicon resin, fluorine resin, etc. Can be used.

Next, the structure of the transfer body to which the formed color toner image is transferred will be described. The transfer body used in the present invention is composed of a transfer body and a transparent resin layer formed on the surface thereof.

Paper, plastic film or the like is used as the transfer body. The transparent resin layer formed on the surface of the transfer body is made of a transparent thermoplastic resin,
Specific examples thereof include styrene resin, (meth) acrylic resin, styrene- (meth) acrylic resin, polyester and the like.

As a method for forming the transparent resin layer on the surface of the transfer body, the above-mentioned thermoplastic resin is dissolved in a solvent such as toluene, acetone, ethyl alcohol, methyl ethyl ketone, tetrahydrofuran or the like, and this is transferred to the transfer body. Examples thereof include a method of coating on a substrate and drying.

The transparent resin layer is preferably formed in a thickness of 20 to 200 μm on the surface of the transfer body in order to form a high quality color image, and particularly preferably in a thickness of 20 to 80 μm. To be taken. When the thickness of the transparent resin layer is less than 20 μm, the toner particles are not sufficiently embedded in the transparent resin layer when the color toner image is fused and fixed,
The color image obtained has many irregularities and lacks in gloss. On the other hand, when the thickness of the transparent resin layer exceeds 200 μm, the color toner image and the transparent resin layer are easily transferred to the belt-shaped heating member, resulting in image defects and surface irregularities, resulting in poor gloss. It becomes an image.

In the present invention, a color toner image is transferred onto a transfer member having the above-mentioned transparent resin layer on its surface, and the transferred color toner image is fixed by a belt-shaped heating member to form a transparent resin layer. When the thermoplastic resin is easily softened and the toner particles are easily embedded, and the releasing property to the belt-shaped heating member is good even in the molten state, and the toner image is peeled from the belt-shaped heating member, It is possible to prevent image floating due to adhesion to the belt-shaped heating member and image loss due to transfer.

In the color image forming method of the present invention, for example, when a color toner image formed on the photosensitive member by an electrophotographic method is transferred to a transfer member, and this is heated, melted and fixed, a color image is formed. Using a transfer body having the above-mentioned transparent resin layer on the surface, a color toner image is embedded in the transparent resin layer, and the transparent resin layer is dyed by thermal diffusion of a heat sublimable dye. A belt-shaped heating member is used for fixing to form a color image.

According to this structure, since the surface of the transfer body on which the color toner image is transferred is heated even while being conveyed by the belt, it is heated for a much longer time than the heating roller system. Becomes Therefore, the transparent resin layer on the surface of the transfer member is sufficiently melted, the toner particles are also in a fluidized state and are easily deformed and embedded easily, and the diffusion time of the heat sublimable dye is sufficiently secured. Further, even when the belt-shaped heating member is peeled off, the releasing property of the belt-shaped heating member from the transfer member and the toner image is good, so that the toner image does not float and the image is not lost due to the transfer.
Therefore, the color image obtained can be a high-quality color image in which diffuse reflection of illumination light is prevented and the glossiness is excellent and the image does not adhere to the belt-shaped heating member.

FIG. 1 shows an example of a fixing device that can be suitably used for fixing a color toner image in the color image forming method of the present invention. This Figure 1
In the fixing device, the color toner attached on the transparent resin layer on the surface of the transfer body is heated by the belt-shaped heating member that moves below the member containing the heat source to melt in the transparent resin layer, and then cooled. Then, the belt-shaped heating member is separated from the transfer member to form a color image. In FIG. 1, 1 is a transfer member, 1'is a transparent resin layer,
Reference numeral 2 is a color toner image, and 3 is a heating roll. The heating roll 3 has a heat source 6 such as an infrared lamp inside.
Further, the heating roll 3 is configured by providing an elastic layer 5 such as rubber on the outer periphery of the core 4 fixed to the rotating shaft. 7
Is a pressure roll, 8a is an upper heat resistant belt, and 8b is a lower heat resistant belt. These heat resistant belts 8a and 8b are formed by treating the surface of a heat resistant resin such as polyimide with a silicone resin. Reference numeral 9 is a peeling roll, and 10 is a pressure roll for the peeling roll 9. Reference numeral 11 is a separation claw of the transfer body 1 provided as necessary, and 12 is a forced cooling device provided as necessary.

In the fixing device of FIG. 1, the transfer body 1 carrying the color toner image 2 is heated and conveyed by the heat-resistant belts 8a and 8b which move below the member having the heat source 6, and the color on the transfer body 1 is transferred. The toner image 2 is melted, fixed, and cooled by the natural air cooling or the forced cooling device 12 to make it difficult to be deformed, and then separated by the peeling roll 9. With such a fixing device, an extremely smooth color image can be obtained.

In the color image forming method of the present invention,
An electrostatic latent image for each color is formed on a photosensitive member by imagewise exposure, and a color toner image is formed by superposing and developing the electrostatic latent image for each color with toners of Y, MC, and BK, and the superposed color toner image. It is preferable to collectively transfer the above to a transfer body and heat-fix this to form a color image.

The color image forming method of the present invention will be described in more detail below. FIG. 2 is a sectional view of a color image forming apparatus that can be used in the method of the present invention, where K is an image reading unit, L is a laser writing unit, M is an image forming unit, and N is a paper feeding unit. The image reading unit K includes the mirror 2
Carriage 2 to which 5 and halogen lamp 24 are attached
2, a movable mirror unit 23 to which the mirrors 26 and 27 are attached, a lens 30, a filter device 32,
It is composed of a CCD 33 and an image processing device 34. The laser writing unit L includes a motor 41, a polygon mirror 42, and the like. The image forming portion M includes the organic photoconductor 4
0, the pre-exposure lamp 45A, and the scorotron charger 45
B, AC bias P1, and DC bias P2 are applied to the developing units 46Y, 46M, 46C, and 46 filled with a developer containing negative toners of Y, M, C, and BK.
BK, a transfer device 47 that collectively transfers the color toner image formed on the organic photoconductor 40 to the transfer member PA or PB, a separator 48, and a fixing device 55 that fixes the color toner image.
The cleaning device 49 is configured to remove the toner remaining on the organic photoconductor 40. The fixing device 55 is shown in FIG.
The configuration is similar to that shown in FIG. The paper feeding section N is provided with a paper feeding cassette 50A or 50
It has delivery rollers 51A and 51B for delivering the transfer body PA or PB from B, and a timing roller 52.

The color image forming method of the present invention can be carried out as follows by using the color image forming apparatus having the above-described structure. That is, the start button is turned “on”, an initialization signal is output to the image reading section K via the control circuit, and the filter device 32 sets the filter to the B filter. At the first rotation of the organic photoconductor 40, the document 20 on the document table 21 of the image reading unit K is
Is optically scanned by the halogen lamp 24 of the carriage 22, and the optical image of the original is passed through the lens 30 and the CCD 33 through the lens group 25, 26, 27 driven by the stepping motor and the filter device 32 in which the B filter is set. An image is formed on the light receiving surface and converted into an electric signal. The obtained electric signal is sent to A in the image processing device 34.
Signal processing such as / D conversion, shading correction, gradation correction, color conversion, ghost processing, and multi-value conversion is performed, and the Y image signal that is the first color signal is output to the next laser writing unit L.

A laser beam oscillated from a laser light source is pulse-width modulated by the Y image signal, rotationally scanned by a polygon mirror 42 which is rotationally driven by a motor 41, and an optical path is bent by a mirror 44 via an fθ lens 43. Then, pre-exposure by the pre-exposure lamp 45A and image exposure are performed on the surface of the organic photoconductor 40 that has been uniformly charged by the charger 45B to form an electrostatic latent image. Next, the electrostatic latent image is non-contactly reversal developed by the developing device 46Y to form a Y toner image. While the obtained Y toner image is held on the organic photoconductor 40,
Of the organic photoconductor 4 for forming the next M toner image by passing under the cleaning device 49 which is separated from the surface of
With the second rotation of 0, the sheet is conveyed to the charger 45B.

The surface of the organic photoconductor 40 on which the Y toner image is carried is uniformly recharged by the charger 45B, and then the filter 32 is switched to the G filter, and the image reading unit K Image exposure of the laser beam based on the M image signal, which is the second color signal from the image processing device 34, is performed to form an electrostatic latent image on the organic photoconductor 40, and the electrostatic latent image is formed by the developing device 46M. Developing unit 46
As in the case of Y, non-contact reversal development is performed, and on the Y toner image,
The M toner images are formed in an overlapping manner.

Similarly, at the third and fourth times of the organic photoconductor 40, image exposure of the laser beam based on the C image signal using the R filter, development by the developing device 46C, and BK image signal using the ND filter are similarly performed. After the image exposure of the laser beam based on the above, and the development by the developing device 46BK, the C toner image and the BK toner image are superimposed on the Y toner image and the M toner image on the organic photoconductor 40 to form a color toner image.

The obtained color toner image is sent out from the cassette 50A at the same timing as the image formation and is sent out from the roller 5
By the action of the transfer device 47, it is collectively transferred onto the transfer body PA conveyed to the transfer area via 1A and the timing roller 52. The transfer body PA on which the color toner image has been transferred is separated from the organic photoconductor 40 by the separator 48, and then conveyed to the fixing device 55 by the conveyor belt 54 and heated and fixed by the fixing device 55 (see FIG. 1). Then, a color image is formed, and the sheet is discharged to the sheet discharge tray 57 by the sheet discharge roller 56.

[0058]

[Example 1]

<Example of Preparation of Yellow Toner> Transparent Cross-Linked Resin Particles Potassium persulfate as a polymerization initiator, sodium thiosulfate, and 600 parts by weight of distilled water were placed in a reaction vessel, and 70
After heating to ℃, while stirring, methylmethacrylate-styrene-divinylbenzene (weight composition ratio; 70:
28: 2) 200 parts by weight were sequentially added dropwise over 2 hours, and the mixture was further reacted for 3 hours after the addition. After completion of the reaction, cooling, filtration and drying are carried out to give transparent crosslinked resin particles having an average particle size of 0.4 μm (softening point 163
C) was prepared. Yellow Toner 20 parts by weight of the transparent cross-linked resin particles obtained above, 70 parts by weight of a polyester resin obtained from etherified bisphenol A-terephthalic acid-fumaric acid, and a heat sublimable dye (compound 11 (a) below) 10 parts by weight of the compound shown below, and kneading, pulverizing,
By classification, a yellow toner “Toner Y1 (for the present invention)” having an average particle diameter of 7.5 μm was produced.

<Preparation example of magenta toner> Chemical formula 11 (a)
A magenta toner “toner M1” having an average particle size of 7.5 μm was prepared in the same manner as in the preparation example of the yellow toner except that the compound represented by Chemical formula 11 (b) was used as the thermal sublimation dye instead of the compound represented by (For the present invention) "was obtained.

<Preparation Example of Cyan Toner> Similar to the preparation example of the yellow toner except that the compound represented by Chemical formula 11 (a) is used as the heat sublimation dye instead of the compound represented by Chemical formula 11 (a). Thus, a cyan toner “Toner C1 (for the present invention)” having an average particle diameter of 7.5 μm was obtained.

[0062]

[Chemical 11]

<Preparation Example of Black Toner> The compound represented by the chemical formula 12 below and the compound represented by the chemical formula 11 (c) above were mixed at a ratio of 3: 1 to prepare a heat sublimation dye. Black toner “Toner BK1” having an average particle diameter of 7.5 μm was prepared in the same manner as in the preparation example of the yellow toner except that the above mixture (thermal sublimation dye) was used in place of the compound represented by Chemical formula 11 (a). (For the present invention) "was obtained.

[0064]

[Chemical 12]

<Preparation Example of Developer> 8 parts by weight of each of the above four types of color toners (Y1, M1, C1, BK1) and 92 parts by weight of a spherical ferrite carrier coated with a styrene-methyl methacrylate copolymer. Were mixed to obtain a total of four types of full-color developers.

<Production of Transfer Material> Styrene-acrylic copolymer resin consisting of styrene-butyl acrylate copolymer (weight composition; 82:17) [weight average molecular weight 12
10,000, softening point 121 ° C, glass transition point (Tg) 56 ° C]
Was dissolved in an acetone solvent at a concentration of 20% by weight, coated on A4 size plain paper with a wire bar and dried to prepare a transfer body having a transparent resin layer with a thickness of 20 μm.

Using these developers, a color image was formed by the color image forming apparatus of FIG. 2 equipped with the belt-shaped fixing device of FIG. The obtained color image has a high image density of 1.33, has no color turbidity, and has excellent color reproducibility.
S-300A Deflection Glossmeter (manufactured by Nippon Denshoku Industries Co., Ltd.) has an image with a glossiness of 88%, which is excellent in glossiness and has high image quality without transfer to a belt-shaped heating member. It was a thing. Further, the transparent resin layer on the surface of the transfer body was dyed to a depth of 6 μm due to the diffusion of the heat sublimable dye.

Comparative Example 1 100 parts by weight of a polyester resin and 10 parts by weight of a colorant (carbon black) were melt-kneaded, pulverized and classified to prepare a comparative BK toner. Further, the colorant was changed to 5 parts by weight of benzidine yellow (for Y toner), 5 parts by weight of rhodamine B (for M toner), and 5 parts by weight of copper phthalocyanine (for C toner), respectively. Y toner, M toner, and C toner (for comparison, respectively) were prepared. Then, a color image was formed in the same manner as in Example 1 except that the above four types of toner were used. Although the obtained color image had an image density of 1.25, it had poor image quality with turbidity, poor color reproducibility, and a glossiness of 67% and poor gloss. The transparent resin layer on the surface of the transfer body was scarcely dyed and had a depth of 1.0 μm or less.

[0069]

As is apparent from the above description, according to the color image forming method of the present invention, a high-quality color having high light transmittance, no color turbidity, and excellent color reproducibility and glossiness is obtained. An effect is obtained that an image is obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an example of a fixing device that can be preferably used in the present invention.

FIG. 2 is a cross-sectional view of an example of a color image forming apparatus that can be used for carrying out the color image forming method of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Transfer body 1'Transparent resin layer 2 Color toner image 3 Heating roll 4 Core 5 Elastic layer 6 Heat source 7 Pressure roll 8a Heat resistant belt 8b Heat resistant belt 9 Peeling roll 10 Pressure roll 11 Separation claw 12 Forced cooling device 20 Manuscript table 21 Document 22 Carriage 23 Movable mirror unit 24 Halogen lamp 30 Lens 32 Filter device 33 CC
D 34 Image processing device 41 Motor 42 Polygon mirror 43 fθ
Lens 45A Pre-exposure lamp 45B Scorotron charger 46Y Yellow developer 46M Magenta developer 46C Cyan developer 46BK Black developer 47 Transfer device 48 Separator 49 Cleaning device PA Transfer unit PB Transfer unit 55 Fixer K Image reading unit L Laser writing Part M Image forming part N Paper feeding part

Claims (1)

[Claims] 1. A color toner having a transparent region by containing a thermally sublimable dye and transparent crosslinked resin particles in a binder resin, and a color toner image is formed by using at least three kinds of the color toner. This color toner image is transferred onto a transfer body having a transparent resin layer made of a thermoplastic resin on its surface, and the color toner image on the transfer body is heated and melted by a belt-shaped heating member to be fixed. And a color image forming method.