JPS6141154A - Image forming particles - Google Patents

Abstract

PURPOSE:To obtain image forming toner particles capable of forming a uniform and sharp color mixture without adversely affecting resolution by incorporating a sublimable dye and its color developer, and when necessary, a nonsublimable colorant same in color as said dye. CONSTITUTION:The toner 1 or 5 is obtained by dispersing the dye 2 sublimable or vaporizable by heating, and its color developer 3, and when needed, a nonsublimable colorant 6 same in color as the dye 2 into a binder resin 4. When necessary, an inorg. fine powder 8 may be added to the toner 1 or 5 to form a porous toner 7. For example, when a toner contg. a yellow sublimable dye and a toner contg. a red sublimable dye are used and a photosensitive material is exposed by using a color original, and developed with each toner, and then heated, the dyes are adsorbed into other particles to form a uniform sharp color mixture, thus permitting color mixing by the subtractive process to be executed, and 3 primary colors to be arranged in mosaic forms or the like, and a sharp color image high in density to be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to image-forming particles used in electrophotography or electrostatic recording, particularly images useful for color recording; The record includes
Colored powder commonly referred to as "powder toner" (hereinafter referred to as toner) has been widely used as an inking material.

Conventional toners generally have a structure in which a mixture of a thermoplastic resin binder and a colorant finely dispersed is made into fine particles. Three types of toner, yellow, magenta, and cyan, are usually used for color recording, and mixed colors are obtained by melting and mixing different types of toner. Therefore, in order to reproduce clear and uniform mixed colors, it is desirable to use a resin binder with as low a melt viscosity as possible.

However, resins with low melt viscosity generally have low melt viscosity, and when used in toner, they cause toner blocking, so they are not suitable for practical use. Therefore, in conventional toners, blocking resistance is more important than melt-mixability, and resins with high softening points (80° C. or higher) are used. Therefore, if you microscopically observe a solid mixed color reproduced with conventional toners, you will find that due to insufficient melting and mixing of different types of toners, you will see a non-uniform color in which 8 different colors are mixed locally. It had some drawbacks.

Further, Japanese Patent Publication No. 55-49307 proposes image forming particles which have both color separation and inking functions and are made by dispersing a sublimable dye in a colored resin binder. The inking material of these particles is a sublimable dye, and the colored image formed on the image receptor is not a fixed image of the particles themselves but a sublimated color image of the sublimable dye contained in the particles. Therefore, when a particle image transferred to an image receptor is heated, the sublimable dye sublimates and diffuses, resulting in a drawback that the resolution of the printed image is poorer than that of a particle image. Furthermore, in order to obtain a high-density color image, it is necessary to use a special image receptor coated with a sublimable dye developer, which has the drawback of increasing the cost of the image receptor.

OBJECTS OF THE INVENTION It is an object of the present invention to overcome the above-mentioned conventional problems and to provide image-forming particles that can provide uniform and clear mixed colors and that do not adversely affect resolution. Another object of the present invention is to provide image forming particles that allow subtractive color mixing even from a two-dimensionally arranged state.

Structure of the Invention The present invention is an image forming particle containing a sublimable dye and a color developer for the dye, which has a function of adsorbing a plurality of sublimable dyes of different colors and developing the colors.

Description of Examples Image forming particles according to the present invention will be described based on the drawings. FIGS. 1 to 3 are schematic cross-sectional views showing the embodiment.

Particles 1 in FIG. 1 are obtained by finely dispersing a mixture of a sublimable dye 2 and a color developer for the sublimable dye (hereinafter referred to as color developer) 3 in a resin binder 4.

Particles 5 in FIG. 2 are particles intended to reduce the content of sublimable dye, including sublimable dye 2, color developer 3, and non-sublimable colorant (hereinafter referred to as colorant) 6. The colored mixture finely dispersed in the resin binder 4 is made into fine particles. Here, the sublimable dye and the colorant have the same hue.

Further, the particles 7 shown in FIG. 3 are particles intended to facilitate the inflow and outflow of sublimable dye gas, and are
Inorganic fine powder 8 is mixed into the particles shown in the figure or FIG. 2.

The particles shown in Figures 1 to 3 all have a structure in which the constituent materials are uniformly dispersed, but for example, the particle surface may be coated with a color developer or a sublimable dye. Of course, a configuration in which some of the constituent materials are laminated in layers is also possible, and there is no limitation to the arrangement form of the constituent materials. Next, specific constituent materials of the particles will be explained.

As the sublimable dye, any dye that sublimates or evaporates (hereinafter referred to as "sublimation") when heated can be used. Preferably, it has excellent storage stability at room temperature and a fast sublimation rate.

Practically speaking, a dye having a sublimation temperature in the range of 60 to 200''C is preferable.Next, typical examples of sublimable dyes will be described.

Disperse dye: C, 1, Disperse Blue 5, C01° Disperse Thread) 1, C1j Disperse Yellow 61° Basic dye: C, 1, Paysic Blue 5, c, r.

Paysic Clean 4, C1! , Hessick Violet 14+ Sublimation color former = 3,7-pisudiethylamino-10-)lichloracetyl-phenoxazine, 7'-
Diethylamino-1,3,3-)dimethyl-5-chloroindolinobenzospiropyran, N-('1,2-dimethyl-3-yl)methylidene-2,4-dimethoxyanili/, As the color developer, the above-mentioned Any material that can develop the sublimable dye may be used. Next, typical examples of color developers useful for each sublimable dye will be described.

For disperse dyes: Acetate, nylon, polyester resin For basic dyes and sublimable color formers: Activated clay,
Electron-accepting substance colorants such as silicon dioxide and 4,4'-diphenylpropane with a pH of 4 or lower are (1) transparent and easily dispersed in resin binders (2) do not sublimate at temperatures below 200°C (3) colors High purity is desirable. Next, typical examples of colorants will be described.

Acid dye: Cj, Acid Red 94, C,1, Acid Flu 1, C0x, Acid Yellow 19 Pigment: C,j Pigment Red 5, C,j Pigment Blue 16, C,1, Pigment Yellow 12 As a resin binder It is preferable that the resin has a softening point of 60° C. or higher, is colorless and transparent, and has excellent binding properties.

For example, styrene resin, acrylic-polyester copolymer, styrene-butadiene copolymer, epoxy resin, etc. can be used.

Further, the image forming particles can be easily made porous by, for example, dispersing and mixing an inorganic fine powder into a resin binder. The inorganic fine powder that meets this purpose is preferably one that can be transparently dispersed in a resin binder. For example, silicon dioxide, aluminum oxide, barium sulfate, zinc oxide, etc. can be provided. Next, the mixing ratio of each of the above-mentioned materials will be explained.

The amount of sublimable dye is 0.1 per 100 parts by weight of resin binder.
-20 parts by weight, color developer 1-30 parts by weight, colorant 0.
The amount of the inorganic fine powder is preferably 1 to 10 parts by weight and 6 to 50 parts by weight.

In addition, in order to impart properties to the image forming particles according to the intended use, such as electrical properties such as charge polarity or conductivity, powder properties such as fluidity, or magnetic properties, charge control agents,
This can be easily achieved by appropriately adding a conductive agent, an antiblocking agent such as silicon dioxide, a magnetic material, etc. to the inside or surface of the above-mentioned particles using a conventional method.

Further, the shape of the image forming particles may be either spherical or amorphous. The particle size is 5 to 2Qμm when used as a dry developer, and 0.1 to 2Qμm when used as a wet developer.
2 μm is preferred.

Specific examples will be described below.

Example 1 10 doses of each of the following formulations and B mixtures were prepared separately.
After sufficiently cross-mixing with a kneader heated to 0°C and cooling, the mixture was atomized with a jet mill to obtain yellow and magenta image-forming particle sizes and B.

<Formulation A> Resin binder: Styrene resin (Nippon Petro@) "Vicola Tinc D-125J (softening point: 126°C))"
・・・・・・・・・・・・ 72 parts by weight sublimable dye:
C, 1, Disperse Yellow 61...
...... 6 parts by weight Color developer: Polyester resin (manufactured by Toyobo Co., Ltd. [Bi r: 57-300J (softening point: 123°C))]・・・・・・
・・22 parts by weight <Formulation B> Resin binder: Styrene resin (same as formular)・・・
・・・・・・・・・・・・ 73 parts by weight Sublimable dye: C
5th Engineering, Disperse Lesodoto...
・・・・・・ 6 parts by weight Color developer: Polyester resin (same as the formulator) ・・・・・・・・・・・・・・・・・・ 2
2 parts by weight Example 2 Yellow and magenta image forming particles C and D were prepared by using a mixture of formulations C and D shown below in the same manner as in Example 1.
I got it.

<Formulation C> Resin binder: styrene resin (same as Example 1)...
・・・・・・・・・・・・・・・ 73 parts by weight Sublimable dye: (,j Disperse Yellow 51・・・・・・・・・・
・・・・・・ 3 parts by weight Colorant; C0X, Pigment Yellow 12・・・・・・・・・・・・・・・・・・
2 parts by weight Color developer: Polyester resin (same as Example 1)
・・・・・・・・・・・・・・・・・・ 22 parts by weight
Formulation D> Resin binder: styrene resin (same as Example 1)...
・・・・・・・・・・・・ 73 parts by weight Sublimable dye: C,
1, Disverse Redst・・・・・・・・・・・・
... 3 parts by weight Colorant: C, Pigment Red 5... 3 parts by weight Colorant: Polyester resin (same as Example 1)...・
21 parts by weight Example 3 A mixture of formulations E and F shown below was produced in the same manner as in Example 1 to obtain image forming particles E of yellow, yellow and magenta. and F
I got it.

<Formulation E> Resin binder: styrene resin (same as Example 1)...
・・・・・・・・・・・・・・・ 61 parts by weight Sublimable dye: C,1, Disperse Yellow 61・・・・・・・・・
・・・・・・・・・ 3 parts by weight Colorant: C, X,
Pigment Yellow 12・・・・・・・・・・・・・・・
... 2 parts by weight Color developer: polyester resin (same as Example 1)
21 parts by weight Inorganic fine powder silicon dioxide (Aerosil R972J manufactured by Nippon Aerosil Co., Ltd.) 13 parts by weight
Prescription F> Resin binder: styrene resin (same as Example 1)...
・・・・・・・・・・・・・・・ 60 parts by weight Sublimable dye: C0x, Dice bar thread・・・・・・・・・
・・・・・・・・・ 3 parts by weight Colorant: CJ Pigment Red 6 ・・・・・・・・・・・・・・・ 3 parts by weight Color developer: Polyester resin (Example 1 same as)·····
・・・・・・・・・・・・・・・ 21 parts by weight Inorganic fine powder silicon dioxide (same as formulation E)・・・・・・・・・・・・
13 parts by weight Next, in order to compare the degree of color mixing between the image forming particles obtained in this example and conventional image forming particles, a mixture of formulations G and H shown below was prepared. Example 1
Conventional type yellow and magenta image forming particles G and H containing no sublimable dye or color developer were prepared by the same manufacturing method.

<Formulation G> Resin binder: styrene resin (same as Example 1)...
・・・・・・・・・・・・・・・ 96 parts by weight Colorant: 0
．． 1. Pigment Yellow 12・・・・・・・・・・・・
...... 5 parts by weight <Formulation H> Resin binder: styrene resin (same as Example 1)...
・・・・・・・・・・・・・・・ 94 parts by weight Colorant:
Cj, Pigment Red 6・・・・・・・・・・・・
...... 6 parts by weight Experiment 1 The above-mentioned image forming particles * Bj ' * "j"
2 F+G and H were adjusted and mixed as shown below to prepare a developer. After classifying the particles to 6 to 15 μm, 1 part by weight of silicon dioxide fine powder (Aerosil #200J manufactured by Nippon Aerosil Co., Ltd.) as a charge control agent was added to 100 parts by weight of the particles, and the mixture was thoroughly shaken and mixed. A negatively charged toner was obtained.Next, 6 parts by weight of the above toner was added to 100 parts by weight of the iron powder carrier and thoroughly stirred and mixed to obtain a developer.

Next, solid yellow and magenta toner images were obtained by the usual Carson process using the developer combinations shown in each example. Next, each toner image was transferred and superimposed on plain paper, and then heat-fixed to obtain a red print image. The image forming conditions are shown below.

Photoreceptor: Selenium photoreceptor Electrostatic image surface potential: +800V Development: Polishing brush development Transfer: Corona transfer (+8KV) Fixing: Heating roller (180°C for 0.5 seconds) Each print obtained in the experiment When the images were observed under a microscope, it was found that the red obtained with the toners of Examples 1.2 and 3 had a particle size of 1 particle.
The pieces were colored red, but in the conventional example, yellow and maze/red were scattered locally.

Experiment 2 After forming yellow and magenta toner images with a line width and pitch of 60 μm under the same image forming conditions as in Experiment 1, the images were transferred to plain paper so that the stripes did not overlap each other and heat-fixed. did.

When each print image obtained in the experiment was observed under a microscope, it was found that the boundary between yellow and magenta in the image obtained with the combination of toners of Examples 1, 2, and 3 had a line width of 30 to 30.
It was a 40μm red band. On the other hand, in the conventional toner combination, the boundary between yellow and magenta is several μm thick.
Only the colors were mixed.

As described in detail, since the image forming particles of the present invention contain a sublimable dye and a color developer, the following effects can be obtained.

(1) When multiple image-forming particles of different colors are overlapped and heated, the sublimable dye contained in the particles sublimates and diffuses, adsorbs to other particles and develops the color, resulting in a uniform and clear mixed color. is obtained.

(2) Since subtractive color mixing is possible without superimposing particles three-dimensionally, for example, when applied to a color image forming method in which three primary colors are arranged two-dimensionally in a mosaic or stripe pattern, it is possible to create clear images with high color density. An image is obtained.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 are schematic cross-sectional views showing embodiments of image-forming particles according to the present invention. 1... Image forming particles, 2... Sublimable dye, 3... Color developer, 4... Resin binder, 5... ...image forming particles, 6...colorant,
7... Image forming particles, 8... Inorganic fine powder. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3

Claims (3)

[Claims] (1) Image-forming particles that visualize electrostatic images and are characterized by containing a sublimable dye and a color developer for the sublimable dye. (2) The image forming particles according to claim 1, further comprising a non-sublimable colorant having the same color as the sublimable dye. (3) Claim 1, wherein the particles are gas permeable.
Image forming particles according to item 1 or item 2.