JPH1158832A - Color image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a color by independently stimulating a plurality of color developing mechanisms by one stimulation source without generating color shift. SOLUTION: Four kinds of microcapules 1Y, 1M, 1C, 1K and color developers 2 are sealed in a filmy sheet 10. The microcapules 1Y, 1M, 1C, 1K develop yellow, magenta, cyan and black respectively and are made different mutually in resonance frequency. The vibrator 32 of a vibration head 31 is driven on the basis of the image signal of each of the colors to be vibrated based on the resonance frequency of each of the microcapsules 1Y, 1M, 1C, 1K and the vibration frequency thereof is applied to the filmy sheet 10 vertically by an ultrasonic lens 33. By this constitution, the microcapsules 1Y, 1M, 1C, 1K are broken to allow the couplers in the microcapsules to flow out and the developers 2 are reacted to develop colors. The filmy sheet 10 after an image is formed is bonded to the whole surface of paper.

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 apparatus for forming a multicolor image on an image forming medium such as paper in one cycle, so-called one shot, using a color developing means such as a microcapsule.

[0002]

2. Description of the Related Art Regardless of an electrophotographic method or an ink jet method, in a color image forming method most frequently used at present, one color printing is performed in one process by one printing mechanism, and a plurality of different colors are recorded. A multi-color image such as a full-color image is obtained by repeating the printing process by the printing mechanism.

On the other hand, a method called one-shot color for obtaining a multicolor image in one cycle has been proposed. This one-shot color method can obtain an image without color shift by processing a plurality of colors simultaneously or in parallel, and can form a multicolor image with one printing mechanism. There is a feature that can be achieved.

[0004] Specifically, Japanese Patent Application Laid-Open No. 60-221765 discloses an electrophotographic color image forming method in which a special photoconductor for forming a multicolor image is exposed to analog exposure image light including three color lights. Thus, a method of forming a multicolor image by one exposure is shown.

Japanese Patent Publication No. 7-71861 discloses a method using microcapsules, in which three types of microcapsules containing a photocurable substance which are cured by irradiation with light having different wavelengths are used. A method of irradiating light having a combination of wavelengths to cure the photocurable substance of the corresponding microcapsule, and then destroying the microcapsule where the photocurable substance is not cured to form a color is shown.

Further, Japanese Patent Application Laid-Open No. 1-184159 discloses that
Similarly, in a method using a microcapsule, a method is described in which a resonance electric field that matches the resonance frequency of the microcapsule is generated between two orthogonal electrodes to destroy the microcapsule and develop color.

[0007]

With the advance of digital technology, image information has recently been often treated as digital information. However, Japanese Patent Application Laid-Open No.
Since the method of 0-221765 uses analog exposure image light, it cannot be used as it is in the case of digital image information, and has the drawback that a special photosensitive member is required.

[0008] The method of Japanese Patent Publication No. 7-71861
Unless light of three wavelengths from the three light sources is concentrated at one point, a color shift occurs. However, in practice, it is difficult to concentrate the light at one point, and there is a disadvantage that the color shift easily occurs.

Although it is conceivable to simultaneously generate light of a plurality of wavelengths from one light source, for example, in the case of a laser light source, it is originally intended to generate laser light of a single wavelength, It is difficult to generate the same light simultaneously.

Furthermore, the method disclosed in Japanese Patent Application Laid-Open No. 1-184159 requires the electrodes for the number of pixels, and the electrodes must be selectively scanned, resulting in a disadvantage that the apparatus becomes large and complicated. In addition, when a multicolor image is formed, the apparatus becomes larger and more complicated.

Therefore, the present invention not only can easily form a multicolor image based on digital image information, but also can stimulate a plurality of types of color-forming mechanisms independently by a single stimulus source without causing color shift to form a color. It is intended to provide a color image forming apparatus capable of performing the above.

[0012]

According to the first aspect of the present invention, there is provided an ultrasonic wave generating means capable of generating ultrasonic waves of a plurality of frequencies based on a color image signal, and an ultrasonic wave applied from the ultrasonic wave generating means. And a plurality of types of coloring mechanisms for independently coloring different colors in accordance with the frequency of the sound waves.

According to a second aspect of the present invention, in the first aspect of the present invention, the resonance frequency of each coloring mechanism is used as the frequency of the ultrasonic wave generated by the ultrasonic wave generating means.

According to a third aspect of the present invention, in the second aspect of the present invention, a plurality of types of color-forming mechanisms are constituted by a plurality of types of microcapsules each containing a color-forming agent and a developer. By applying ultrasonic waves having a resonance frequency, the microcapsules are destroyed, and the color former comes into contact with the color developer,
The corresponding color shall be developed.

According to a fourth aspect of the present invention, in the third aspect of the invention, a plurality of types of microcapsules and a developer are encapsulated in a single film-like sheet, and the entire surface of the film-like sheet is used as an image forming medium. The image is transferred onto the image forming medium by bonding.

According to a fifth aspect of the present invention, in the third aspect of the present invention, a plurality of types of microcapsules are encapsulated in a single film-like sheet, and a color developer is applied on an image forming medium, and the broken microcapsules are applied. When the color former of the capsule is transferred onto the image forming medium and comes into contact with the developer, the color is developed.

According to a sixth aspect of the present invention, in the third aspect of the present invention, each of the plurality of types of microcapsules is filled with a gas.

According to a seventh aspect of the present invention, in the first aspect of the present invention, the ultrasonic wave generating means is provided with an ultrasonic lens.

[0019]

According to the first aspect of the present invention, the ultrasonic vibration energy is used as a stimulus for a plurality of types of coloring mechanisms, and the frequency of the ultrasonic wave from one ultrasonic generating means is selected, so that a specific frequency is obtained. A coloring mechanism that develops a color only in response to an ultrasonic stimulus develops a color.

Therefore, a plurality of types of coloring mechanisms can be stimulated independently by one stimulus source without causing a color shift to develop a color. Also, since the frequency of the ultrasonic wave can be easily selected based on the digital image information,
A multicolor image can be easily formed based on digital image information.

According to the second aspect of the present invention, since the resonance frequency of the coloring mechanism is used as the frequency of the ultrasonic wave, energy for coloring can be obtained with less vibration energy.

According to the third aspect of the present invention, it is possible to realize a preferable and practical coloring mechanism that develops a color by stimulation of an ultrasonic wave.

According to the fourth aspect of the present invention, since the microcapsules and the color developer constituting the color-forming mechanism are encapsulated in a single film-like sheet, the storage container and the transport when the powder or liquid coloring material is used. Means for securing a route are not required, and the size of the apparatus can be reduced, and contamination due to scattering of the coloring material inside and outside the apparatus can be prevented.
Further, since the entire surface of the film-like sheet is adhered to the image forming medium, means for collecting the used film-like sheet is not required, and the cost of the apparatus can be reduced.

According to the fifth aspect of the present invention, the color forming agent of the broken microcapsules transfers color onto the image forming medium coated with the color developing agent, and color is formed only before the ultrasonic wave is applied. Since the agent is separated in the film-like sheet and on the image forming medium, erroneous coloring does not occur.

According to the sixth aspect of the present invention, since the gas is sealed in the microcapsule, the resonance frequency for breaking the capsule can be reduced, and the efficiency of the ultrasonic vibration energy is increased and the cost of the device is reduced. be able to.

According to the seventh aspect of the present invention, since the ultrasonic wave generating means is provided with the ultrasonic lens, it is possible to prevent the spread of the energy due to the spread of the vibration and the disturbance of the image.

[0027]

FIG. 1A shows an example of a color forming mechanism used in an image forming apparatus of the present invention. Four types of microcapsules 1Y, 1M, 1C,
1K and the developer 2 are enclosed.

Four types of microcapsules 1Y, 1M, 1
C and 1K develop yellow, magenta, cyan, and black, respectively, as described later. However,
In the figure, the microcapsules 1Y, 1Y are for convenience of identification.
Although the sizes of M, 1C, and 1K are all changed, it is not always necessary to change all the sizes as described later. Hereinafter, the four types of microcapsules 1Y, 1M, 1C, and 1K are collectively referred to as microcapsules 1.

As shown in FIG. 1 (B), each of the microcapsules 1 is formed by an internal component 1a and an outer membrane 1b containing the same, and the internal component 1a includes the above-described developer 2 In addition to the coloring agent which forms a color by reacting with air bubbles, air bubbles for lowering the resonance frequency of the microcapsule 1 are included.

As a color former, a leuco dye such as a fluoran type, a triphenylmethane type, a phenothiazine type,
Auramine type, spiropyran type and the like can be used. For example, rhodamine B lactam, 3-diethylamino-5,7-dimethylfluoran, 3-dimethylamino-6-methoxyfluoran, 3,3-bis (P-dimethyl (Aminophenyl) -6-aminophthalide, benzoyl leucomethylene blue and the like can be used.

As the color former, a material that develops a predetermined color when reacted with the developer 2 is selected. In the above example, yellow is used as the microcapsule 1Y and yellow is used as the microcapsule 1M. A material that develops magenta, cyan as the microcapsule 1C, and black as the microcapsule 1K is used.

Examples of the developer 2 include phenolic compounds such as α-naphthol, β-naphthol, resorcin, hydroxyn, catechol, pyrogallol, activated clay, and organic carboxylate.

Then, the microcapsules 1Y, 1M, 1
As will be described later, C and 1K differ from each other in resonance frequency depending on the size of the capsule, the material and thickness of the outer membrane 1b, and the like. Thereafter, the microcapsules 1Y, 1M, 1
Let the resonance frequencies of C and 1K be fy, fm, fc,
fk.

It is desirable that the microcapsule 1 does not come into contact with an adjacent one so as not to hinder resonance. Therefore, it is desirable to cover each microcapsule 1 with a liquid or a jelly-like substance.

FIG. 2 shows an example of the image forming apparatus of the present invention. In this example, the film-like sheet 10 enclosing the microcapsules 1 and the color developing agent 2 as described above is wound into a roll and fed out by a feed-out roller 20.

Then, as will be described later, the vibration head 31 of the ultrasonic generator 30 is driven based on the image signals of yellow, magenta, cyan, and black, and
Generates ultrasonic waves having the above-mentioned frequencies fy, fm, fc, and fk, and applies the ultrasonic waves to the film-like sheet 10 to break the microcapsules 1Y, 1M, 1C, and 1K. Form a multicolor image.

The film-like sheet 10 on which the multicolor image is formed is passed between the transfer rolls 41 and 42 and is entirely adhered to the sheet 61 supplied from the sheet supply tray 51 by pressure or heat. The sheet 62 to which the film sheet 10 is adhered is discharged from the sheet discharge tray 52 to the outside of the apparatus.

In general, the resonance frequency f of a capsule in which gas is sealed is determined by the following equation: f = (1 / 2πr) (3 kP / ρ) ^1/2 (1) That is, the factors that determine the resonance frequency f of the capsule are the particle diameter (outer diameter) r of the capsule, the coefficient k determined by the material and thickness of the film, and the pressure difference P between the inside and outside of the film. By determining the resonance frequency f and applying a vibration of the frequency f, the capsule can be selectively broken.

Actually, in the capsule structure shown in FIG. 1B and described above, the microcapsule 1 is selected by adjusting the particle size of the microcapsule 1 in which air is sealed and the material of the outer membrane 1b. Tried to destroy it.

FIG. 3 shows the experimental apparatus. The microcapsules 1 are arranged side by side on a piezo vibrator 71, and the high frequency from the function generator 81 is supplied to the high frequency amplifier 8.
Amplified in step 2 and supplied to the piezo vibrator 71, the piezo vibrator 71 was given a large vibration. Vibration frequency is 10kHz
The range was changed from z to 1 MHz.

In order to accurately grasp the state of breakage of the microcapsule 1, a weight 72 was placed on the microcapsule 1 and pressure was applied from above the microcapsule 1. Also,
In order to transmit the vibration of the piezoelectric vibrator 71 to the microcapsule 1 more efficiently, silicone as a jelly-like substance was applied to the surface of the piezoelectric vibrator 71 and the bottom surface of the weight 72. Further, the microcapsule 1 was surrounded by a capsule 1E having a different rigidity so as not to be broken so that the pressure distribution due to the weight 72 would not be uneven. The destruction state of the microcapsule 1 was measured as a physical quantity by an image processing device through a microscope.

FIG. 4 shows the particle size of the four types of microcapsules P, Q, R, and S used in this experiment and the material of the outer membrane. The particle size is 10 μm and 20 μm, and the outer membrane material is polymethyl methacrylate and polyvinylidene chloride. The combination of the particle size and the outer membrane material is four kinds of microcapsules P, Q, R, Different at S. Particle size of 10 μm and 2
In order to make it uniform to 0 μm, after the capsules were produced, those that had been classified by a precision sieve (sieve) were used.

FIG. 5 shows the destruction rate of the microcapsules P, Q, R, and S with respect to the vibration frequency based on the results of the experiment. It was found that for each of the microcapsules P, Q, R, and S, there was a vibration frequency with a high capsule breaking rate, and the capsule was broken by resonance. In addition, the frequency at which the capsule is broken is in the order of several tens of kHz to several hundreds of kHz, which is a frequency that can be sufficiently realized as a printing apparatus.

FIG. 6 shows a specific example of the above-mentioned ultrasonic generator 30 constructed using the phenomenon obtained in this experiment. In this example, the vibration head 31 is provided with an ultrasonic lens 33 on the front side of the vibrator 32, and applies an AC voltage from a frequency-variable AC voltage applying device (not shown) to the vibrator 32, The four types of microcapsules 1Y, 1M, 1C, 1K and the developer 2 are
Irradiates the enclosed film-shaped sheet 10 vertically.

Four types of microcapsules 1Y, 1M, 1
C and 1K are all changed in size in FIG. 6 for the sake of convenience, but the combination of the particle size and the material of the outer membrane is changed to the four types of microcapsules P, Q, R, and S shown in FIG. It is changed like this.

Then, the microcapsules 1Y, 1M, 1
A vibration wave having a resonance frequency of C, 1K is applied to the film-like sheet 10.
Is applied to the microcapsules having the resonance frequency of the vibration wave, a large distortion accompanied by a vibration mode occurs, and the microcapsules are destroyed.
As shown in FIG. 7, the coloring agent 5 flows away from the broken microcapsules 3 and reacts with the color developing agent 2 to develop a corresponding color.

To print a secondary color by simultaneously destroying two of the microcapsules 1Y, 1M, and 1C at the same position on the film-like sheet 10, the waveforms of the two frequencies are superimposed and vibrated on the vibrator 32. Is also conceivable. However, in this case, the vibration of the vibrator 32 uses the greatest common divisor of the frequency of each waveform before superimposition as the vibration frequency, and the microcapsule may not be destroyed.

Therefore, the traveling of the film-like sheet 10 is made step-like, and as shown in FIG. 8, one pixel period corresponding to the one step is divided into time, and the vibration of the frequency f1 is reduced in the previous period T1. In the subsequent period T2, vibration of two frequencies is applied, such as applying vibration of frequency f2. As a result, the secondary color can be reliably developed. Similarly, a tertiary color can be developed.

The microcapsules which emit yellow, magenta, cyan, black, red, green and blue, respectively, have different resonance frequencies.
Different types can be used, and according to this, a secondary color can be generated without using the above-described time division.

Further, as can be seen from the effect of acoustic overtones, resonance occurs even at an integer multiple of the fundamental resonance frequency. For example, when the resonance frequencies of two types of microcapsules are 100 kHz and 150 kHz, 300k
When a vibration wave of Hz is applied, the energy of resonance is reduced, but the two types of microcapsules are also resonated and destroyed. Utilizing this phenomenon, it is also possible to produce a secondary color without using time division.

In the above-described example, a plurality of types of microcapsules and a developer are encapsulated in one film-like sheet. However, the plurality of types of microcapsules are encapsulated in a film-like sheet. The developer is applied on the paper, and for example, in a state where the film-shaped sheet and the paper are stacked, ultrasonic waves are applied to the film-shaped sheet to break the microcapsules, and the color developing agent of the broken microcapsules is applied to the paper. May be brought into contact with a color developer to develop color.

[0052]

As described above, according to the present invention, a plurality of types of coloring mechanisms can be stimulated independently by a single stimulus source without causing a color shift to produce a color. Simplification can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a coloring mechanism used in an image forming apparatus according to the present invention.

FIG. 2 is a diagram illustrating an example of an image forming apparatus according to the present invention.

FIG. 3 is a diagram showing an apparatus used in an experiment performed to confirm the principle of the present invention.

FIG. 4 is a diagram showing the particle size and material of four types of microcapsules used in the experiment.

FIG. 5 is a diagram showing the results of the experiment.

FIG. 6 is a diagram illustrating an example of an ultrasonic generator of the image forming apparatus according to the present invention.

FIG. 7 is a diagram schematically showing a state of color development due to destruction of a microcapsule.

FIG. 8 is a diagram for explaining generation of vibrations of a plurality of frequencies by time division.

[Explanation of symbols]

 1, 1Y, 1M, 1C, 1K Microcapsule 2 Developer 10 Film-like sheet 20 Feeding roll 30 Ultrasonic generator 31 Vibration head 32 Vibrator 33 Ultrasonic lens 41, 42, 43 Transfer roll 61, 62 Paper

Claims (7)

[Claims] An ultrasonic wave generating means capable of generating ultrasonic waves of a plurality of frequencies based on a color image signal, and different colors depending on the frequency of the ultrasonic wave applied from the ultrasonic wave generating means. A color image forming apparatus comprising: a plurality of types of color forming mechanisms that independently form colors. 2. The color image forming apparatus according to claim 1, wherein the frequency of the ultrasonic wave generated by the ultrasonic wave generating means is:
A color image forming apparatus using a resonance frequency of each of the coloring mechanisms. 3. The color image forming apparatus according to claim 2, wherein the plurality of kinds of color forming mechanisms are constituted by a plurality of kinds of microcapsules each containing a color forming agent and a color developing agent, and the microcapsules have the same. A color image forming apparatus, wherein the microcapsules are destroyed by the application of ultrasonic waves having a resonance frequency, and the color former contacts the developer to produce a corresponding color. . 4. The color image forming apparatus according to claim 3, wherein the plurality of types of microcapsules and the developer are encapsulated in a single film sheet, and the entire surface of the film sheet is used as an image forming medium. A color image forming apparatus, wherein an image is transferred onto the image forming medium by being adhered. 5. The color image forming apparatus according to claim 3, wherein said plurality of types of microcapsules are encapsulated in a single film-like sheet, and said developer is applied on an image forming medium, and said microcapsules are destroyed. A color image forming apparatus, wherein a color is formed by transferring the color former of the capsule onto the image forming medium and contacting the developer. 6. The color image forming apparatus according to claim 3, wherein a gas is sealed in each of the plurality of types of microcapsules. 7. The color image forming apparatus according to claim 1, wherein said ultrasonic wave generating means includes an ultrasonic lens.