JP2002244384A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device by which a stereoscopic full-color image having sufficient durability is inexpensively formed. SOLUTION: In the image forming device by which a stereoscopic color image is formed on a supporting body, a color toner image consisting of nonfoamable full-color toner is formed on a toner image consisting of heat- foamable toner formed on the surface of the supporting body, and the color toner image consisting of the nonfoamable full-color toner is not formed over minute width at the outline part of the toner image consisting of the heat- foamable toner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a printer or a copying machine to which an electrophotographic system or an electrostatic recording system is applied, and more particularly to an image forming apparatus capable of forming a three-dimensional image by using a foaming toner. The present invention relates to a forming apparatus.

[0002]

2. Description of the Related Art Conventionally, various techniques have been devised in a technique for forming a three-dimensional image, and various techniques have been proposed. For example, a technology to perform three-dimensional printing by plastically deforming the support (paper) by dot impact, a technology to perform three-dimensional printing using thermal foaming toner, or a technology to perform three-dimensional printing using foamed paper or a thermal transfer film There are various techniques, such as a technique of performing three-dimensional printing by printing an ultraviolet-curable resin, and a technique of performing three-dimensional printing by performing transfer many times using a conventional toner.

However, the above-mentioned techniques for performing various types of three-dimensional printing are for forming a three-dimensional image consisting of simple irregularities without color or a three-dimensional black-and-white image, and an image forming method for forming a three-dimensional full-color image. And a technique for defining the image structure after fixing has not been proposed at all. From a technical point of view, it is extremely difficult to superimpose a full-color image on a three-dimensional convex part of paper or the like in an image forming process and post-processing, and a full-color three-dimensional image having high durability and high storage properties is formed. An image forming apparatus has not been proposed until now.

Further, there is a technique for three-dimensionally deforming a support such as paper by post-processing embossing of a full-color image of a poster or the like, but it takes a lot of time, man-hours, and time to form a mold for embossing. It requires cost, is only applied to the production of a large number of copies, and in terms of durability, since the paper is plastically deformed to obtain a convex image, it is flattened when pressed lightly with a finger or the like. Has problems.

Accordingly, the applicant of the present invention has disclosed “image forming toner, a method of manufacturing the same, a method of forming a three-dimensional image and an image forming apparatus using the same,” and “image forming apparatus” using a foamable toner. No. 10-304458, Japanese Patent Application No. 11
No. 3111710 and Japanese Patent Application No. 2000-3066.
No. 9 and other publications.

[0006]

However, the prior art described above has the following problems. That is, as described above, the present applicant has proposed “image forming toner, a method of manufacturing the same and a method of forming a three-dimensional image and an image forming apparatus using the same,” and “image forming apparatus” using an expandable toner. However, there is no disclosure about an image forming method for forming a three-dimensional full-color image and a technique for defining an image structure after fixing.

Although Japanese Patent Application No. 10-304458 discloses that a three-dimensional full-color image can be formed with a thermally foamable color toner in which a coloring material is internally added to a binder resin, This has not yet been put to practical use. Technically, when trying to obtain a full-color image by color superimposition with a heat-foamable color toner containing a YMCK color material, the shell of the foaming agent internally added to the toner has a light transmittance. However, there is a problem that pictorial color development cannot be obtained in principle due to light refraction by the air bubble layer. In addition, a method in which a non-expandable full-color YMCK toner is simply superimposed on the expandable toner may be considered. However, the non-expandable full-color toner is more flexible and compressive than the expandable toner. Since the resistance (non-destructive property) is significantly inferior, distortion occurs between the support such as paper and the lateral wall surface of the foamed toner image due to shearing force due to finger rubbing or the like, and as shown in FIG. There has been a problem that the non-foamable full-color toner image is destroyed at the boundary line with the body and is dropped (deleted).

Accordingly, the present invention has been made to solve the above-mentioned problems of the prior art, and an object thereof is to provide a three-dimensional full-color image having sufficient durability at a low cost. An object of the present invention is to provide an image forming apparatus that can be formed.

[0009]

According to an aspect of the present invention, there is provided an image forming apparatus capable of forming a three-dimensional color image on a support. A color toner image formed of a non-expandable full-color toner is formed on the toner image formed of the heat-expandable toner, and a fine width is formed on the contour of the toner image formed of the heat-expandable toner. In this manner, a color toner image composed of a non-foamable full-color toner is not formed.

Further, according to a second aspect of the present invention, a toner image formed of a heat-expandable toner and a color toner image formed of a non-expandable full-color toner are transferred onto the surface of the support, and then heated and fixed. By processing
2. The image forming apparatus according to claim 1, wherein the three-dimensional image is formed by foaming the thermally foamable toner, and the color image is formed by fusing and fixing a color toner image formed of a non-foamable toner. It is.

Further, in the invention according to a third aspect of the present invention, the heat-foamable toner is foamed by transferring a toner image composed of the heat-foamable toner to the surface of the support and then performing a heat fixing process. To form a three-dimensional image, and then, after transferring a color toner image composed of a non-foamable full-color toner on the surface of the support on which the three-dimensional image is formed,
2. The image forming apparatus according to claim 1, wherein a color image is formed by fusing and fixing a color toner image made of a non-foamable toner by performing a heat fixing process.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1 FIG. 2 shows an electrophotographic color printer as an image forming apparatus according to Embodiment 1 of the present invention. FIG. 3 shows an electrophotographic color copying machine as an image forming apparatus according to Embodiment 1 of the present invention.

2 and 3, reference numeral 1 denotes a main body of a color printer and a color copying machine. As shown in FIG. An original reading device 4 for reading an image of the original 2 is provided. The document reading device 4 converts the document 2 placed on the platen glass 5 into a light source 6.
The reflected light image from the original 2 is scanned and exposed on an image reading element 11 such as a CCD through a reduction optical system including a full rate mirror 7, half rate mirrors 8 and 9, and an imaging lens 10. , This image reading element 11
Thereby, the color material reflected light image of the original 2 is read at a predetermined dot density (for example, 16 dots / mm).

The color material reflected light image of the original 2 read by the original reading device 4 is, for example, original reflectance data of three colors of red (R), green (G), and blue (B) (8 bits each). Is sent to the image processing apparatus 12, and the image processing apparatus 12 performs shading correction, position shift correction, lightness / color space conversion, gamma correction, frame erasure, color / movement editing on the reflectance data of the document 2. And other predetermined image processing.

The image data subjected to the predetermined image processing by the image processing device 12 as described above includes yellow (Y), magenta (M), cyan (C), and black (B
K) ROS13 (Raster Output Scann) as four-color original color material gradation data (8 bits each)
er), and the ROS 13 performs image exposure using laser light according to the original color material gradation data.

An image forming means A capable of forming a plurality of toner images of different colors is provided inside the color printer and the copying machine main body 1. This image forming means A
Mainly, ROS 13 as an image exposure unit, a photosensitive drum 14 as an image carrier on which an electrostatic latent image is formed,
A rotary developing device 15 as a developing unit capable of developing an electrostatic latent image formed on the photosensitive drum 14 to form a plurality of toner images of different colors.

As shown in FIGS. 2 and 3, the ROS 13 modulates a semiconductor laser (not shown) in accordance with original reproduction color material gradation data, and emits a laser beam LB from the semiconductor laser in accordance with gradation data. I do. Laser light LB emitted from the semiconductor laser is deflected and scanned by a rotating polygon mirror (not shown), and is scanned and exposed on a photosensitive drum 14 as an image carrier via an f · θ lens and a reflection mirror (not shown).

The photosensitive drum 14 on which the laser light LB is scanned and exposed by the ROS 13 is driven to rotate at a predetermined speed in a direction indicated by an arrow by a driving means (not shown). The surface of the photosensitive drum 14 is
After being charged to a predetermined polarity (for example, negative polarity) and potential by the primary charging scorotron 16 in advance, a laser beam LB is scanned and exposed according to the original reproduction color material gradation data to form an electrostatic latent image. It is formed. After the surface of the photosensitive drum 14 is uniformly charged to, for example, -650 V, the image portion is scanned and exposed to laser light LB to form an electrostatic latent image having an exposed portion of -200 V. The electrostatic latent image formed on the photosensitive drum 14 is
Developing units 15Y, 15M, 15C of four colors of yellow (Y), magenta (M), cyan (C), and black (BK)
For example, a toner (charged color material) charged to a negative polarity having the same polarity as the charged polarity of the photoreceptor drum 14 is reversely developed by the rotary developing device 15 provided with the 15BK to form a toner image T of a predetermined color. . At this time, a developing bias voltage of, for example, -500 V is applied to the developing rolls of the developing units 15Y, 15M, 15C, and 15BK. The toner image T formed on the photosensitive drum 14 is charged with a negative polarity by a pre-transfer charger 17 as necessary, and the charge amount is adjusted.

The toner images of the respective colors formed on the photosensitive drum 14 are transferred onto an intermediate transfer belt 18 as an intermediate transfer member disposed below the photosensitive drum 14 by a first transfer means 18 as a first transfer means. The image is multiplexed and transferred at the first nip portion N1 by the next transfer roll 19. This intermediate transfer belt 1
Reference numeral 8 denotes a drive roll 20, a driven roll 21, a tension roll 22, and a backup roll 23 as an opposing roll constituting a part of the secondary transfer means, at the same moving speed as the peripheral speed of the photosensitive drum 14 in the direction of the arrow. It is supported rotatably along.

On the intermediate transfer belt 18, yellow (Y), magenta (M), cyan (C), and black (BK) are formed on the photosensitive drum 14 according to the color of the image to be formed. All or some of the four color toner images are
The images are transferred in a state of being sequentially superimposed by the primary transfer roll 19. The toner image T transferred onto the intermediate transfer belt 18 is transferred to a recording paper 24 as a recording medium conveyed to a secondary transfer position N2 at a predetermined timing by a backup roll 23 supporting the intermediate transfer belt 18 and The transfer is performed by the pressing force and the electrostatic attraction force of the secondary transfer roll 25 which constitutes a part of the second transfer means which presses the backup roll 23. The recording paper 24 is, as shown in FIGS. 2 and 3, a color printer and a copying machine main body 1.
A sheet of a predetermined size is fed by a feed roll 27 from a sheet feeding cassette 26 as a plurality of recording medium housing members arranged at a lower portion of the inside. Fed recording paper 2
46 denotes a plurality of transport rolls 28 and registration rolls 29
As a result, the intermediate transfer belt 18
The sheet is transported to the next transfer position N2. Then, as described above, the recording paper 24 is formed on the recording paper 24 by the backup roll 23 and the secondary transfer roll 25 as a secondary transfer unit.
A predetermined color toner image is collectively transferred from the intermediate transfer belt 18.

The recording paper 24 on which the toner image of a predetermined color has been transferred from the intermediate transfer belt 18 is separated from the intermediate transfer belt 18 and then conveyed to a fixing device 30. The toner image is fixed on the recording paper 24 by heat and pressure by the heating roll 31 and the pressure roll 32, and is discharged to the outside of the color printer and the copying machine main body 1, thereby completing the color image forming process.

2 and 3, reference numeral 33 denotes a cleaning device for removing residual toner, paper dust, and the like from the surface of the photosensitive drum 14 after the completion of the transfer process, and reference numeral 34 denotes cleaning of the intermediate transfer belt 18. , A cleaner for cleaning the secondary transfer roll 25 is shown. Further, the intermediate transfer belt cleaner 34 and the cleaner 35 of the secondary transfer roll 25 are configured to come into contact with and separate from the intermediate transfer belt 18 at a predetermined timing.

In this embodiment, in an image forming apparatus capable of forming a three-dimensional color image on a support, a toner image formed of a thermofoamable toner formed on the surface of the support is provided. A color toner image composed of a non-foamable full-color toner is formed, and a color toner image composed of a non-foamable full-color toner is not formed over a minute width on the contour of the toner image composed of the thermally foamable toner. It is configured as follows.

Further, in this embodiment, a heat fixing process is performed after a toner image made of a heat-foamable toner and a color toner image made of a non-foamable full-color toner are transferred to the surface of the support. Thus, a three-dimensional image is formed by foaming the heat-foamable toner, and a color image is formed by fusing and fixing a color toner image made of a non-foamable toner.

That is, in the first embodiment, in a state where the expandable toner image and the non-expandable full-color toner image are transferred onto the intermediate transfer member on a support such as paper, FIG.
As shown in (1), a non-foamable full-color toner image is formed only on the upper surface of the thermo-foamable toner image, and a non-foamable full-color toner image is not formed on the side surface (inclined surface) of the thermal foamable toner image. Forming a non-foamable full-color toner image, forming a color superimposed image so that the non-foamable full-color toner image at that time is not continuously brought into contact with a support such as paper, and collectively transferring the image to a support such as paper; The fixing device is configured to form a three-dimensional full-color image by simultaneously performing (one-shot) the foaming / thermal fusion of the foamable toner and the thermal fusion of the non-foamable full-color toner. I have.

The developing system may be any of a two-component developing system, a non-magnetic one-component developing system, and a magnetic one-component developing system for a foamable toner. In the present embodiment, the two-component developing system is adopted. An image is formed. The toner composition may contain a wax that enables oil-less heat fixing, or may not contain a wax, for both the foamable toner and the non-foamable full-color toner. Both non-foamed color toners
An image is formed with a soft-roll fixing device equipped with an oil system using a toner containing no wax.

In the first embodiment, in the rotary developing device 15, the developing devices 15Y, 15M, 15C of four colors of yellow (Y), magenta (M), cyan (C), and black (BK) are used. , 15BK, for example, in a black (BK) developing unit 15BK or a newly added white developing unit 15WH (not shown), an image forming toner containing at least a binder resin and a foaming agent. In this case, the toner is configured such that the foaming agent is not substantially exposed to the toner surface.

The foaming agent is not particularly limited, and any material can be used as long as it expands by heat. It may be solid at room temperature or liquid. Further, the foaming agent is not limited to a material composed of a single substance, and may be a material composed of a plurality of substances or a functional material such as microcapsule particles. The preferred range of the foaming temperature of the foaming agent varies depending on the type of apparatus used to form the three-dimensional image, but the three-dimensional image is formed using a normal printer or copier as shown in FIGS. In this case, the foaming temperature is preferably equal to or lower than the heat fixing temperature.

As the foaming agent, for example, a foaming agent mainly composed of a substance which generates gas by thermal decomposition can be used, and specifically, sodium bicarbonate or the like which generates carbon dioxide gas by thermal decomposition can be used. Examples include bicarbonate, a mixture of NaNO ₂ and NH ₄ Cl that generate nitrogen gas, azo compounds such as azobisirobutyronitrile and diazoaminobenzene, and peroxides that generate oxygen and the like.

As another form of the foaming agent, a foaming agent for microcapsule particles containing a low-boiling substance that vaporizes at a low temperature (which may be in a liquid state or a solid state at ordinary temperature) (hereinafter, referred to as “a”). Microcapsule type foaming agent "). Microcapsule type foaming agent
It is preferable because the foaming property is high. When the image forming toner of the present embodiment is used in a normal printer, a copying machine, or the like, the low-boiling substance contained in the microcapsules can be vaporized at least at a temperature lower than the heat fixing temperature. It is necessary, and specifically, is a substance which vaporizes at 100 ° C or lower, preferably 50 ° C or lower, more preferably 25 ° C or lower. However, since the thermal responsiveness of the microcapsule type foaming agent depends not only on the boiling point of the low-boiling substance as the core material but also on the softening point of the wall material, the preferred boiling point range of the low-boiling substance is not limited to the above range. . Examples of the low boiling point substance include neopentane, neohexane, isopentane, isobutylene, isobutane, and the like. Above all, isobutane which is stable to the wall material of the microcapsule and has a high coefficient of thermal expansion is preferable.

The wall material of the microcapsules has solvent resistance to various solvents used in the process of manufacturing the toner, and when the low-boiling substances contained in the microcapsules are vaporized, they are not resistant to gas. Materials having permeability are preferred. Further, when the image forming toner of the present embodiment is used in a normal printer, a copying machine, or the like, the wall material needs to soften and expand at a temperature lower than the heat fixing temperature. As the wall material of the microcapsules, conventionally used wall materials can be widely used. For example, homopolymers such as polyvinyl chloride, polyvinyl acetate, polystyrene, polyacrylonitrile, polybutadiene, and polyacrylate, and copolymers thereof are preferably used. Among them, a copolymer of vinylidene chloride and acrylonitrile is preferred because of its high adhesiveness to a binder resin and its high solvent resistance to solvents.

The preferred range of the content of the foaming agent in the toner of the present embodiment varies depending on the type of the foaming agent, but is usually 5% by weight to 50% by weight, preferably 10% by weight to 40% by weight. . If the content of the foaming agent is less than 5% by weight, the thermal expansion of the toner may be insufficient in practical use. On the other hand, if it exceeds 50% by weight, the ratio of the binder resin in the toner may be relatively low. In some cases, problems may occur, such as shortage and insufficient fixability.

The binder resin of the toner for forming a three-dimensional image according to this embodiment is not particularly limited, and a resin generally used as a toner resin can be used. Specifically, polyester resin, styrene resin, acrylic resin, styrene / acrylic resin, silicone resin, epoxy resin, diene resin, phenol resin, ethylene /
A vinyl acetate resin or the like is preferable, and a polyester resin is more preferable.

The binder resin of this embodiment may be a combination of two or more of the above polyester resins, or may be a combination of other resins. Other resins include styrene resin, acrylic resin, styrene / acrylic resin,
Silicone resin, epoxy resin, diene resin, phenol resin, terpene resin, coumarin resin, amide resin,
There are natural wax resins such as amide imide resin, butyral resin, urethane resin, ethylene / vinyl acetate resin, polypropylene resin, polyethylene resin and carnauba wax. In the present embodiment, the polyester resin is the main component, and the other resin is 0 to 30% by weight in the toner.
Is preferably added. When a toner is prepared by dispersing a foaming agent in a monomer of the binder resin and subjecting them to suspension polymerization, a monomer capable of suspension polymerization in the binder resin can be used.

FIG. 4 shows an example of a schematic diagram in which the toner particles of the present embodiment are cut and the section is observed with a microscope. As shown in FIG. 4, the toner particles 40 of the present embodiment include at least a binder resin 41 and foaming agent particles 42, and the foaming agent particles 42 are included in the toner core without losing foamability. Have been. Image forming toner 4 of the present embodiment
No. 0 has a structure in which the foaming agent 42 is not substantially exposed to the surface, and thus has a high thermal expansion property and also maintains good adhesion to a recording medium and good charge stability.

The expression "substantially not exposed to the surface" as used herein means that, for example, as a result of observing an electron micrograph of 50 toner particles, as shown in FIG. Indicates that 80% or more of the toner is not exposed. Further, as shown in FIG. 4, it is preferable that the foaming agent 42 is uniformly dispersed as particles in the toner, because the adhesion of the toner to the recording medium and the charging stability can be further improved.

The image forming toner of the present embodiment may contain a coloring agent as desired, and may be colored and visualized. As the colorant to be dispersed, known organic or inorganic pigments and dyes, and oil-soluble dyes can be used. These colorants depend on the toner particle size and the amount of development, but generally a ratio of about 1 to 100 parts by weight with respect to 100 parts by weight of the toner is appropriate.

Further, the toner for forming an image of the present embodiment may contain a magnetic substance for giving magnetization.
Known types of magnetic materials can be used as appropriate.
Further, the image forming toner of the exemplary embodiment may contain a release agent, if desired. It is preferable to include a release agent because an offset phenomenon or the like at the time of contact fixing can be prevented. The image forming toner of the present embodiment may optionally include a charge control agent. Further, the image forming toner of the present embodiment includes:
A known external additive may be added for controlling the fluidity and the developing property.

The toner for forming an image according to the present embodiment is, for example, an oil phase in which at least a binder resin and a foaming agent are dissolved and / or dispersed in a solvent, and the oil phase is suspended and dispersed in an aqueous phase. And a step of removing a solvent from the particles.

Further, the image forming toner of the present embodiment is prepared by a process including a process of suspending and polymerizing a binder resin monomer in which at least a foaming agent is dissolved or dispersed in an aqueous phase. Is also good.

The toner for forming an image used in this embodiment is a white toner containing 75% by weight of a binder polymer as a binder resin and 25% by weight of Expancel 461 as a foaming agent, and a binder as a binder resin. This black toner contains 74.1% by weight of a polymer, 24.7% by weight of Expancel 461 as a foaming agent, and 1.2% by weight of carbon black as a coloring agent. An external additive may be added to these image forming toners as needed.

When a white toner is used as the image forming toner, a dedicated developing device containing the white toner is prepared, and the white developing device is mounted on the yellow (Y), Magenta (M), cyan (C), black (BK) developing units 15Y, 15M, 1
5C, 15BK, black (BK) developing unit 15
It may be replaced with BK or a new white developing device may be used.

FIG. 5 shows an image of the white toner produced as described above taken with an electron microscope, and FIG. 6 shows an image of the black toner taken with an electron microscope. The volume average particle diameter of these white toner and black toner was about 30 μm.

With the above configuration, the image forming apparatus according to this embodiment can form a three-dimensional full-color image having sufficient durability at a low cost as follows. I have.

That is, in the color printer and the copying machine according to the first embodiment, first, as shown in FIG. 7A, yellow, yellow, Magenta, cyan, and black toner images are sequentially formed.
The yellow, magenta, cyan, and black toner images sequentially formed on the intermediate transfer belt 18 are sequentially and multiplexly transferred onto the intermediate transfer belt 18 as shown in FIG. 7B. That is,
As shown in FIGS. 2 and 3, the surface of the photosensitive drum 14 is uniformly charged to, for example, -650 V by a scorotron 16 for primary charging, and then the ROS 13 is used to form a desired full-color image. The image portion is scanned and exposed with the laser beam LB to form an electrostatic latent image having an exposed portion of -200V. The electrostatic latent image formed on the photosensitive drum 14 is developed with yellow (Y), magenta (M), cyan (C), and black (BK) developing devices 15Y, 15M, and 15C of a rotary developing device 15. , 15B
K, reverse developed, yellow (Y), magenta (M),
The toner images T of cyan (C) and black (BK) are formed. At this time, the developing units 15Y, 15M, 15C,
For example, a developing bias voltage of -500 V is applied to the developing roll of 15BK. As shown in FIG. 7B, the toner image formed on the photosensitive drum 14 is primary-transferred sequentially onto the intermediate transfer belt 18 by a primary transfer roll 19.

At this time, yellow (Y), magenta (M), cyan (C), and black (BK) toners are sequentially formed on the photosensitive drum 14 and primarily transferred onto the intermediate transfer belt 18. The image T is not formed in the same manner as a normal full-color image, and the contour 50 of the three-dimensional image formed by the white toner is next shown in FIG.
As shown in (a), a predetermined minute width (several μm to 40 μm)
) Is set so that a full-color toner image is not formed. In order not to form a full-color toner image over a predetermined minute width on the contour 50 of the three-dimensional image, the edge of the three-dimensional image is detected by the edge detection circuit of the image processing device 12, and the edge of the three-dimensional image is , So that a full-color toner image is not formed over a predetermined minute width. At this time, as shown in FIG. 8 (b), a gap is set at the edge of the three-dimensional image over a predetermined minute width on the outer periphery of the three-dimensional image.
As shown in FIG. 8 (c), a gap may be set on the inner periphery of the stereoscopic image over a predetermined minute width.
When a full-color toner image is formed, black (BK) toner may be used to express black. However, in order to avoid an increase in the size of the rotary developing device 15, black (BK) is used. When the foaming toner is used in the developing unit 15BK, a process black in which yellow, magenta, and cyan toners are superimposed may be used.

Next, in the color printer or copier according to the first embodiment, as shown in FIG. 7, a white toner as a foaming toner is used in accordance with an image formed three-dimensionally on the photosensitive drum 14. Is used to form a toner image. That is, in the first embodiment, for example, the foamable white toner is accommodated in a white (WH) developing device (not shown) of the rotary developing device 15 and the electrostatic latent image formed on the photosensitive drum 14 is formed. The image is developed. At this time, the surface of the photoreceptor drum 14 is, as shown in FIGS. 2 and 3, by a scorotron 16 for primary charging.
For example, after being uniformly charged to -650 V, ROS13
The laser beam LB is scanned and exposed on a desired image portion on which a three-dimensional image is to be formed, thereby forming an electrostatic latent image having an exposed portion of -200V. When forming a three-dimensional image, the electrostatic latent image formed on the photosensitive drum 14 is reversely developed by a white (WH) developing device containing a foaming toner, and becomes a white toner image T. . At this time, the developing roll of the white (WH) developing device includes, for example,-
A developing bias voltage of 500 V is applied.

As a result, a toner image having a toner weight per unit area of 3 mg / cm ² is formed on the photosensitive drum 14. The toner image formed on the photosensitive drum 14 is transferred to the intermediate transfer belt 1 by a primary transfer roll 19.
8 is primarily transferred.

By the above-described image forming process, a three-dimensional image is formed on the intermediate transfer belt 18 on a full-color toner image composed of yellow, magenta, cyan, and black toner images as shown in FIG. The toner image composed of the white foamable toner to be formed is transferred in a multiplex manner.

Thereafter, the full-color toner image of yellow, magenta, cyan, and black transferred on the intermediate transfer belt 18 and the white foamable toner image to form a three-dimensional image are transferred to the secondary transfer position N2. In FIG. 7, the secondary transfer is collectively performed on the recording paper 24 as shown in FIG.

FIG. 9 schematically shows only the foamable toner image T secondary-transferred onto the recording paper 24. FIG. 8 shows only the foamable toner image T secondary-transferred onto the recording paper 24 taken by an electron microscope. As shown in FIGS. 9 and 10, for example, a toner image T in which foamable toner particles 40 are laminated in about two layers is transferred onto the recording paper 24. The height of the unfixed toner image T was 55 to 60 μm. Then, a full-color toner image is further transferred onto the foamable toner image T in a laminated state.

Next, the recording paper 24 on which the three-dimensional image formed of the expandable toner particles 40 and the full-color toner image formed of the non-expandable toner are transferred is fixed as shown in FIGS. The heating roller 31 and the pressure roller 32 of the container 30 undergo a fixing process by heat and pressure, and the binder resin 41 in the toner 40 is melted.
The three-dimensional image and the full-color image are fixed on the recording paper 24 by foaming the foaming agent 42 therein. In the three-dimensional image fixed on the recording paper 24, as shown in FIG. 11, a foaming agent 42 in the toner particles 40 foams to form a substantially spherical or substantially elliptical hollow gas bubble 43. The gas bubbles are in a state of being laminated. The gas bubbles 43
Is covered with a binder resin 41 which has been melted into a film. Then, a full-color image is simultaneously color-fixed on the upper surface of the three-dimensional image fixed on the recording paper 24 and on the recording paper 24.

FIG. 12 is an electron microscope photograph of a three-dimensional image of the foamed toner fixed on the recording paper 24 as described above. The height of the toner image T after fixing was 130 μm.

In FIG. 12, the fixing temperature is 150 ° C., and the nip width between the heating roll 31 and the pressure roll 32 is 4.8 m.
m, the fixing process was performed under the conditions of a fixing speed of 35 mm / sec.

As is apparent from FIG. 12, it is understood that the toner image T is formed three-dimensionally on the recording paper 24 in a highly foamed state. Also, this stereoscopic image 44
Is a gas bubble 4 in which the foaming agent 42 in the foamed toner 40 is foamed.
3 is formed in a state where a plurality of layers (about 3 to 5 layers) are stacked.

FIG. 13 is an electron microscope photograph of a three-dimensional image fixed on the recording paper 24, which is further enlarged and photographed.

As is apparent from FIG. 13, a hollow gas bubble 43 which is substantially uniformly foamed in a substantially spherical or substantially elliptical shape.
It can be seen that a plurality of layers (about 3 to 5 layers) are densely stacked.

FIG. 14 shows the surface of the three-dimensional image fixed on the recording paper 24 and the interface between the toner and the paper.
It is the electron micrograph which image | photographed by enlarging.

As is apparent from FIG. 14A, a state in which hollow gas bubbles 43 foamed in a substantially spherical shape or a substantially elliptical shape are arranged substantially uniformly on the surface of the three-dimensional image. Further, as is clear from FIG.
The binder resin 41 of the toner 40 is provided at the interface between
It can be seen that is partially permeated into the fibers of the recording paper 24.

In the first embodiment, as shown in FIGS. 1 and 8, a foamable toner image and a non-foamable full-color toner image are formed on an intermediate transfer member 18 on a support 24 such as paper. In the transferred state, a non-foaming full-color toner image is formed only on the upper surface of the thermal foaming toner image, and a non-foaming full-color toner image is not formed on the side surface (inclined surface) of the thermal foaming toner image. Then, a non-foaming full-color toner image is formed, and a color superimposed image is formed so that the non-foaming full-color toner image at that time is not continuously brought into contact with a support such as paper, and is collectively transferred to a support 24 such as paper. Then, in the fixing device 30, a three-dimensional full-color image is formed by simultaneously performing (one-shot) the foaming / thermal fusion of the foamable toner and the thermal fusion of the non-foamable full-color toner. It has become.

For this reason, even when the above-described support such as paper is folded, as shown in FIG. 1, a gap 50 having a very small width is formed in the contour of a three-dimensional image made of foaming toner. A three-dimensional full-color image that has sufficient durability without any tension or compression force acting on the full-color image formed at the outline of the image, without breaking the non-foamable color toner image Can be formed at low cost.

Embodiment 2 FIG. 15 shows Embodiment 2 of the present invention. The same parts as those of the above embodiment are denoted by the same reference numerals and described. After transferring the toner image composed of the heat-foamable toner to the surface of the support, by applying a heat fixing process, the heat-foamable toner is foamed to form a three-dimensional image, and then the three-dimensional image is formed. A color toner image composed of a non-foamable full-color toner is transferred to the surface of the support, and then subjected to a heat-fixing process. Is formed.

That is, in Embodiment 2, FIG.
As shown in (1), an expandable toner image is formed, transferred to a support such as paper, and a non-foamable full-color toner image is formed after the expandable toner is expanded and thermally fused by a fixing device. ,
First, a non-foamable full-color toner image is formed only on the upper surface of the thermally foamable toner image on a support such as paper on which the foamable toner image has been foamed and thermally fused, and the side of the thermally foamable toner image (inclined) The non-expandable full-color toner image is transferred onto the surface (side) so that the non-expandable full-color toner image is not formed, and the non-expandable full-color toner is thermally fused by a fixing device to form a three-dimensional full-color image. It is configured as follows.

The other configuration and operation are the same as those of the first embodiment, and the description thereof will be omitted.

[0066]

As described above, according to the present invention, a three-dimensional full-color image having sufficient durability can be obtained.
An image forming apparatus that can be formed at low cost can be provided.

[Brief description of the drawings]

1 (a) and 1 (b) show Embodiment 1 of the present invention.
FIG. 2 is a schematic diagram illustrating a full-color stereoscopic image formed by the image forming apparatus according to the first embodiment.

FIG. 2 is a configuration diagram showing an electrophotographic color printer as an image forming apparatus according to Embodiment 1 of the present invention.

FIG. 3 is a configuration diagram showing an electrophotographic color copying machine as an image forming apparatus according to Embodiment 1 of the present invention.

FIG. 4 is a schematic diagram illustrating toner formed by the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 5 is a drawing substitute photograph showing an electron micrograph of the toner formed by the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 6 is a drawing substitute photograph showing an electron micrograph of a toner formed by the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 7 is an explanatory diagram illustrating a forming process of a full-color stereoscopic image formed by the image forming apparatus according to the first embodiment of the present invention.

FIGS. 8A to 8C are a plan configuration diagram and a cross-sectional configuration diagram illustrating a full-color stereoscopic image formed by the image forming apparatus according to the first embodiment of the present invention.

FIG. 9 is a schematic diagram showing an unfixed toner image formed by the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 10 is a drawing substitute photograph showing an electron microscope photograph of an unfixed toner image formed by the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 11 is a schematic diagram illustrating a stereoscopic image formed by the image forming apparatus according to Embodiment 1 of the present invention;

FIG. 12 is a drawing substitute photograph showing an electron microscope photograph of a fixed toner image formed by the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 13 is an electron micrograph showing a fixed toner image formed by the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 14 is a drawing substitute photograph showing an electron microscope photograph of a fixed toner image formed by the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 15 is a schematic diagram illustrating a full-color stereoscopic image formed by the image forming apparatus according to Embodiment 2 of the present invention;

FIG. 16 is a schematic diagram illustrating a full-color stereoscopic image formed by a conventional image forming apparatus.

[Explanation of symbols]

14: photosensitive drum, 15: developing device, 21: intermediate transfer belt, 30: fixing device, 40: toner particles, 41: binder resin, 42: foaming agent, 43: gas bubble, WH: foamable toner, Y , M, C, BK: non-foamable toner.

Claims (3)

[Claims] 1. An image forming apparatus capable of forming a three-dimensional color image on a support, wherein a non-foamable full-color toner is formed on a toner image formed of a thermally expandable toner formed on the surface of the support. A color toner image formed of a non-expandable full-color toner is not formed over a minute width in a contour portion of the toner image formed of the heat-expandable toner while forming a color toner image of the same color. Characteristic image forming apparatus. 2. The method according to claim 1, further comprising the step of transferring a toner image composed of a thermofoamable toner and a color toner image composed of a non-foamable full-color toner onto the surface of the support, and then performing a heat-fixing process. 2. The image forming apparatus according to claim 1, wherein a three-dimensional image is formed by foaming the toner, and a color image is formed by fusing and fixing a color toner image made of a non-foamable toner. 3. A three-dimensional image is formed by transferring a toner image composed of a heat-foamable toner onto the surface of the support and then subjecting the toner image to a heat fixing process to foam the heat-foamable toner. After transferring a color toner image composed of a non-foamable full-color toner on the surface of the support on which the three-dimensional image is formed, by performing a heat fixing process,
2. The image forming apparatus according to claim 1, wherein a color image is formed by fusing and fixing a color toner image made of a non-foamable toner.