JPH02245764A - Image forming medium and image forming method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming medium and an image forming method that can visualize information charges formed on the image forming medium.

[Conventional technology]

Conventionally, electrodes are deposited on the photoconductive layer, the entire surface of the photoconductive layer is charged by corona charging in a dark place, and then exposed to strong light to make the photoconductive layer conductive in the exposed areas. By leaking and removing the charge, an electrostatic latent image is optically formed on the surface of the photoconductive layer, and a toner having a charge of the opposite polarity (or a charge of the same polarity) as the residual electrostatic charge is deposited. There is an electrophotographic technology that involves electrostatic transfer and development on paper, etc., and this is mainly used for copying, but because of its low sensitivity, it cannot be used for shadowing, and the photoconductive layer is used as a recording medium. Since the retention time of the electrostatic charge is short, it is common to develop the toner immediately after forming the electrostatic latent image.

Further, as shown in FIG. 3(a), a transparent electric bridge 13 and a thermoplastic resin 11 are sequentially laminated on an insulating layer support 14, and selenium particles 4 are deposited on the surface of the thermoplastic material layer by a vapor deposition method.
A recording medium 3 is prepared by infiltrating the thermoplastic material layer 11, and the surface of the thermoplastic material layer 11 is fully charged with a corona charger 3 as shown in FIGS. It is known that a latent image is formed by generating photocarriers in fine particles, and during development, as shown in the same figure (C), the thermoplastic resin is softened by resistance heating 17, and the photoconductive resin in which photocarriers have been generated is softened by resistance heating 17. It is known that information is visualized by moving only thermoplastic particles into a softened thermoplastic material layer (U.S. Pat. Nos. 3,520,681, 4,101,321, 4,496,
642 Specification).

[Problem to be solved by the invention]

However, a thermoplastic material layer having a selenium particle layer is provided on a transparent electrode, the entire surface is corona charged, imagewise exposed, the thermoplastic material is softened and thermally developed, and the accumulated charge is reproduced as visible information. Makes information extremely persistent (
10 years or more), but since corona charging is required to record the information, there are limitations as a means of recording information using cameras, etc. Furthermore, the resolution is limited by the selenium particle size. However, there is a problem in that it is difficult to form high-resolution images.

The present invention relates to a high-resolution image forming medium and an image forming method in which charge information can be easily visualized.

[Means to solve the problem]

In the image forming medium of the present invention, an electrode is provided on a substrate, and a thermoplastic resin layer, an electrophoretic material layer or an electrochromic layer, and an insulating layer are sequentially laminated on the electrode, or an electrophoretic material layer or an electrochromic layer,
Thermoplastic resin layers are sequentially laminated, the substrate, electrode, thermoplastic resin layer, and insulating layer are transparent or semitransparent, and the electrophoretic material layer is an ionized dye layer and an ionized pigment layer. This is a characteristic feature.

The image forming method of the present invention includes a photoconductor consisting of a photoconductive layer provided with an electrode on the front surface, a transparent or semi-transparent substrate on the rear surface, a transparent or semi-transparent electrode on the substrate, and a transparent or semi-transparent electrode on the electrode. Alternatively, an image forming medium in which a translucent thermoplastic resin layer, an electrophoretic substance layer or an electrochromic layer, and a transparent or semitransparent insulating layer are sequentially laminated is placed between the photoconductive layer surface of the photoreceptor and the image forming medium. The method is characterized in that the surfaces of the insulating layers are placed facing each other in contact or non-contact, pattern exposure is performed while applying a voltage between both electrodes, and after exposure, the image forming medium is thermally developed.

The image forming medium of the present invention will be explained below.

FIG. 1(a) is a sectional view of the image forming medium of the present invention;
b) is a sectional view of an image forming medium according to another embodiment of the present invention, in which 3 is an image forming medium, 10 is an insulating layer, and 11 is a cross-sectional view of an image forming medium according to another embodiment of the present invention.
12 is a thermoplastic resin layer, 13 is an electrode, and 14 is a support.

The thermoplastic resin layer is formed of a thermoplastic resin material having a specific resistance value of 1014 to 10" Ω・cm, and is softened during thermal development, and generates electricity by an electric field formed by the image charge accumulated in the insulating layer 10. The ionized dye and ionized pigment in the migrating material layer can be diffused toward the electrode.

Examples of thermoplastic resins include polyethylene, vinyl chloride resin, polypropylene, styrene resin, ABS resin, polyvinyl alcohol, acrylic resin, acrylonitrile-styrene resin, vinylidene chloride resin, AAS (A
SA) resins, ABS resins, cellulose derivative resins, thermoplastic polyurethanes, polyvinyl butyral, poly-4-methylpentene-1, polybutene-1, rosin ester resins, etc., and fluororesins such as polytetrafluoroethylene, fluorinated ethylene Propylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, or their dispersion type or modified type (coating type), as well as polyparaxylene shown by the following structural formula (the above C type is the above In addition to the structural structure, it is acceptable as long as one of the benzene ring sites other than the main chain binding site is substituted with chlorine, and for D type, two of the sites are substituted with chlorine.) etc. is particularly desirable, and since the image is to be reproduced as a visible image by transmitted light after the image is formed, the resin needs to be transparent or translucent after the film is formed. In addition, the thermoplastic resin layer is formed by melting the above-mentioned resin by cutting, coating,
The layer can be formed by dipping, vapor deposition, or sputtering. The thickness of the resin layer is at least 1 μm or more, and preferably 100 μm or less from the viewpoint of flexibility.

As an electrophoretic substance, first, a cationic dye whose counter anion is a halogen (C1-1■, etc.), or a halogen compound <Cll0-C10! -IJ03-, BF4
-, PF6-, etc.) can be used, and the entire molecule is a cation or an anion, such as diarylmethane, triarylmethane, thiazole, methine, xanthine. , oxazine-based, thiazine-based, azine-based, acridine-based, and azo-based dyes can be used, and metal complex salt dyes (center metal, chromium, cobalt, etc.) can also be used.

Ionic pigments can also be suitably used. Examples of ionic pigments include soluble azo pigments as shown in the following formula, such as those made insoluble by forming a water-soluble base into a metal lake, and organic pigments forming metal complexes, such as phthalocyanine. It is recommended to use pigments.

These electrophoretic material layers are made of thermoplastic resin, silicone resin, styrene-butadiene copolymer resin, epoxy resin, acrylic resin, unsaturated or saturated polyester resin, polycarbonate resin, polyvinyl alcohol resin,
Phenol resin, polymethyl methacrylate resin, melamine resin, polyimide resin, etc. are dissolved or dispersed in a binder and formed by coating on the above thermoplastic resin layer, or only electrophoretic substances are formed by sputtering, vapor deposition, etc. is formed on a thermoplastic resin layer, and its film thickness is 0. It is preferable to set the thickness to about 1 μm-10 μm.

In addition, an electrochromy layer may be provided in place of the electrophoretic material layer. This method utilizes the fact that a reversible oxidation-reduction reaction occurs in the electrochromic layer, causing color development.

Like the electrophoretic substance layer described above, this electrochromic layer can also be formed by laminating it on a thermoplastic resin layer by coating, vapor deposition, or the like.

Electrochromic layer forming materials include tungsten oxide (WOs), molybdenum oxide (Moot), vanadium oxide (VzOs), heptyl viologen, polyviologen complex, tetrathiofulvalene, pasophenanthroline complex, and oxidized materials that develop color by reduction. Iridium oxide (IrO+), rhodium oxide (
Rhoyo), nickel oxide (Nip.

), chromium oxide (Crow), Prussian blue complex, ruthenium purple complex, indium nitride (InN
), polythiophene (polypyrrole), styryls, and those that develop redox color include rare earth phthalocyanines and anthraquinone-pyrazoline mixtures.

As the insulating layer laminated on these electrophoretic material layers and electrochromic layers, it is preferable to use insulating resin materials with a high glass transition temperature, such as fluororesin, polyetheretherketone resin, polyparaxylylene resin, etc. can be used, and are laminated to a film thickness of 0.1 μm to 10 μm by film lamination, coating method, smoke coating method, etc., and 1 μm to 5 μm is particularly preferable.

The support 14 supports the image forming medium 3 with strength, and its material and thickness are not particularly limited as long as it has a certain level of strength that can support the resin layer. For example, it may be flexible. A rigid body such as a flexible plastic film, paper, glass, or plastic sheet is used, and light transmittance is required.

Specifically, when the image forming medium 3 takes the form of a flexible film, tape, or disk, a flexible plastic film is used; when strength is required, a rigid sheet, glass, etc. is used. Inorganic materials etc. are used.

The electrode 13 is formed on a support, and its material is not limited as long as its specific resistance value is 10'Ω·C- or less, and I To
(IngOs-5nOg), S n O! Transparent electrodes coated by sputtering, vapor deposition, etc., or by making ink from fine powder of these materials with a binder,
A translucent electrode made by vapor deposition or sputtering of Au, AI, Ag, Ni, Cr, etc., an organic transparent electrode made by coating with tetracyanoquinodimethane (TCNQ), polyacetylene, etc. are used. In addition, the film thickness must be changed depending on the electrical properties of the material constituting the electrode and the applied voltage during information recording, but it is between 100 and 300 mm.
Approximately 0 people.

Next, image formation on the image forming medium of the present invention is performed by accumulating image charges in the insulating layer.

A discharge electrode may be used as a method for accumulating image charges on the image forming medium, but the method is such that the image forming medium is placed facing a photoreceptor having a photoconductive layer laminated on the electrode, and exposed by applying a voltage between both electrodes. It can be accumulated by

An example of the method of forming an image on an image forming medium according to the present invention is shown in FIG.

The photoreceptor 1 shown in FIG. 2 has a photoreceptor electrode 7 on a support 5.
, a photoconductive layer 9 are laminated. To produce an electrostatic image recording device using this photoreceptor and an image forming medium, as shown in FIG. 2, the photoconductive layer surface of the photoreceptor and the resin layer surface of the image forming medium are brought into contact, or
Alternatively, they are stacked facing each other in a non-contact state, and in the case of non-contact, it is preferable to maintain non-contact mechanically or to face the ends of the photoreceptor and the image forming medium with a spacer interposed therebetween.

It also depends on what information input method you use.
Of course, spacers may be placed at appropriate locations on the photoreceptor surface and the image forming medium surface.

In the case of non-contact, the distance between the photoreceptor and the image forming medium is 1 to 5
A suitable value is 0 μm, and the spacer can be made of an organic material such as plastic or an inorganic material such as glass.

First, the method of forming an image on an image forming medium according to the present invention will be described in the case where a cationic dye is used as the electrophoretic substance. First, the photoreceptor 1 is formed by forming a transparent photoreceptor electrode 7 made of A1O with a thickness of 1000 on a photoconductive layer support 5 made of glass with a thickness of 1fi, and on this a hole transporting material such as selenium of about 10 μm is applied. The photoconductive layer 9 is formed by forming a photoconductive layer 9. 10 μm for this photoreceptor 1
The image forming medium 3 is placed with a gap of about 100 mm between each other.

The image forming medium 3 is a support 14 made of glass with a thickness of 1fi.
A 1,000-layer thick A1 electrode was deposited on top, a thermoplastic resin layer was formed on this electrode with a thickness of about 10 μm, a cationic dye layer was further formed with a thickness of 1 μm, and an insulating layer was formed with a thickness of 1 μm. It is.

First, as shown in FIG. 2(a), 10
．． The image forming medium 3 is set through a gap of approximately cam size, and a voltage is applied between the electrodes 7 and 13 by the power source 17. In this example, a positive voltage is applied to the photoreceptor electrode side. Since the photoconductive layer 9 is a high resistor in the dark, if the voltage applied to the gap is below the discharge starting voltage according to Paschen's law,
No change occurs between the electrodes, and when a voltage higher than the discharge starting voltage is applied to the gap by an external power source, a discharge occurs, charge is accumulated in the insulating layer, and this state continues until the voltage drops to the discharge starting voltage. , which becomes a fog charge.

When 1G of light is incident from the photoreceptor 1 side, the photoconductive layer 9 in the area where the light is incident exhibits conductivity, a discharge occurs between it and the insulating layer of the image forming medium, and positive charges are accumulated in the insulating layer. . Further, even if there is a uniform capri charge in advance, charges are further accumulated in the portion where light is incident.

Next, the power supply 17 is turned off, and the image forming medium 3 is peeled off from the photoreceptor 1, or without being separated, the electrode 13 is heated by resistance as shown in FIG. When the layer is heated and thermally softened, an electric field formed by the information charges causes the electrophoretic material in the area where the information charges are accumulated to diffuse toward the electrode substrate. When the heating is stopped, the resin hardens again, the diffused particles remain in that position, and the information charge is converted into position information. When the image forming medium formed in this manner is observed under transmitted light, light does not pass through the non-diffused electrophoretic material layer portions, but light passes through the diffused electrophoretic material layer portions and is exposed to light. A visible image corresponding to the amount can be obtained.

Although the case where the electrophoretic material layer is formed from a cationic dye is described above, the same applies to the case where other ionizable dyes or ionizable agents are used, and electrochromic material is used instead of the electrophoretic material layer. Even when a layer is used, diffusion of the electrochromic layer is not involved, but the image forming method is the same.

When the image forming method of the present invention is used for planar analog recording,
Since the information is in units of electrostatic charge, high resolution can be obtained similar to silver salt photography, and the information charge is fixed in the resin layer as positional information and can be stored for a long period of time.The electrostatic image recording medium of the present invention There are two methods for inputting information: a high-resolution electrostatic camera and a laser recording method. First, high-resolution electrostatic cameras use a photoreceptor and an image-forming medium as a recording member instead of the photographic film used in conventional cameras. Then, during recording, a voltage is applied to the image electrode, and the photoconductive layer becomes conductive according to the incident light, and charges are accumulated on the insulating layer according to the amount of incident light, thereby forming an electrostatic latent image of the incident optical image. It is formed on a medium and can use either a mechanical shutter or an electric shutter.

For recording methods using lasers, the light sources include argon laser (514,488 nm), helium-neon laser (633 nm), and semiconductor laser (780 nm).
(nm, 810 nm, etc.), and a voltage is applied to the photoreceptor and the image forming medium either by bringing the surfaces of the photoreceptor and the image forming medium into close contact with each other, or by facing each other at a certain interval. In this case, it is best to set the photoreceptor electrode to the same polarity as the carrier of the photoreceptor. In this state, laser exposure corresponding to image signals, character signals, code signals, and line drawing signals is performed by scanning. Analog recording is done by modulating the laser light intensity, and digital recording such as characters, codes, &IN is done by ON/OFF control of the laser light, and halftone dots are formed in the image. In this method, dots are formed by applying dot generator ON-OFF4 control to a laser beam. Note that the spectral characteristics of the photoconductive layer in the photoreceptor do not need to be panchromatic, but only need to be sensitive to the wavelength of the laser light source.

[Effect]

When the electrophoretic material layer in the image forming medium of the present invention is an ionizable dye layer, the information charges are transferred to the insulating layer by resistive heating of the image forming medium electrodes or by other means. When the material is heated and thermally softened, the electric field formed by the information charges causes the ionized dye in the region where the information charges are accumulated to diffuse toward the electrode substrate due to the Coulomb force with the electrode substrate. When the heating is stopped, the resin hardens again, the diffused particles remain in that position, and the information charges are converted into positional information.0 When the image forming medium is observed from the i3 direction from the direction of the electrode substrate, an electrophoretic substance that does not diffuse is observed. Light does not pass through the layer portion, but light passes through the diffused electrophoretic material layer portion, and an image corresponding to the amount of exposure can be obtained.

In addition, when the electrophoretic substance layer is made of ionized pigment, the metal ions in the ionic pigment diffuse toward the electrode due to the electric field formed by the information charge, and the ionic pigment layer changes color. The corresponding image can be reproduced as visible information.

In addition, in those using an electrochromy layer, a reversible redox reaction is caused in the electrochromy layer by making the thermoplastic resin layer conductive due to the electric field formed by the information charges accumulated in the insulating layer and heating. By coloring, information charges can be visualized.

When the electrostatic image recording method of the present invention is used for planar analog recording, high resolution can be obtained because the information is in electrostatic charge units, and the information charge can be easily converted into visible information, and the visible information is transferred to the resin layer. fixed inside and stored for a long time.

Examples will be described below.

[Example 1] 10 g of rosin ester resin (10 steverite ester) as a thermoplastic resin and 50 g of tetrahydrofuran
Using a solution dissolved in g, Al was spinner coated (1000 rp
m, 90 seconds).

As a result of leaving it for 1 hour at 60°C to dry the solvent,
A uniform coating having a thickness of 5 μm was formed.

On this medium, crystal bioleft (
(manufactured by Udougaya Kagaku ■) was mixed with polyvinyl butyral resin at a weight ratio of 1%, and a 10% dichloroethane solution was coated on the rosin ester resin layer in the same manner to form a 1 μm thick ionized dye layer.

Next, a fluororesin (Cytotsubu, Asahi Glass) was coated on the ionizable dye layer, and after drying, an insulating layer with a thickness of 1.5 μm was laminated thereon to produce an image forming medium of the present invention.

Next, as shown in FIG. 2(a), the So-based photoreceptor a-3e) 1 prepared in the reference example described below and the image forming medium 3 were combined using a polyester film with a thickness of 0 μm as a spacer. The surface of the insulating layer 10 is grounded facing the photoconductive layer 9 of the photoreceptor 1, and a DC voltage of +7QOV is applied between the two electrodes 7.13 with the photoreceptor side being positive and the resin layer side being negative. .

With the voltage applied, exposure 16 was performed for 1 second using a halogen lamp with an illuminance of 1000 lux from the photoreceptor side, and as a result, a surface potential of +350 V was formed in the exposed area. After the exposure, the image forming medium 3 is removed as shown in FIG.
is taken out, and the image forming medium is heated to 80°C by resistance heating 17.
As a result of heating, the ionized dye moved to the white part of the resin.

When the image forming medium thus formed was irradiated with transmitted light from the t1 side, a visible image was formed due to the shading of the ionized dye.

[Example 2] An image forming medium was prepared in the same manner as in Example 1, using -atchung Red as an ionizable pigment in place of the ionizable dye in Example 1. Then, the polarity of the applied voltage was reversed, and the image forming medium was photosensitive. When an image was formed in the same manner as in Example 1 using a polyvinyl rubber trinitrofluorene organic photoreceptor, the color changed from red to orange in the exposed area, and the information charge was converted into visible information depending on the degree of color change. was confirmed.

[Example 3] Similar to Example 1, a thermoplastic resin layer was provided on the electrode substrate,
Tungsten oxide was laminated thereon to a thickness of 1 μm by EB evaporation, and a fluororesin (Sight Tsubu, Asahi Glass) was coated thereon to a thickness of 1.5 μm to produce an image forming medium.

When the film was then observed using transmitted light, it was confirmed that the electrochromy layer in the exposed portion of the electrochromy layer had changed color to blue, and that the information charges had been converted into visible information.

[Reference Example 1] 10 g of poly-N-vinylcarbazole (Anan Perfume Co., Ltd.)
), 10 g of 2.4.7-trinitrofluorenone, 2 g of polyester resin (binder: Byron 200 manufactured by Toyobo Co., Ltd.), 90 g of tetrahydrofuran (THF)
A mixed solution having the composition was prepared in a dark place, and rnt03-5
Apply nO1 to a spuntered glass substrate (1 piece thick) with a film thickness of about 1000 using a doctor blade.
The mixture was dried with ventilation at 0° C. for about 1 hour to obtain a photoreceptor having a photoconductive layer with a thickness of about 10 μm. In addition, in order to completely dry the sample, it was further air-dried for one day before use.

[Reference Example 2] A-3s-
A Te GL film was deposited on an ITO glass substrate using a resistance heating method at a vacuum level of 10-' Torr. The film thickness was 1 μm. Furthermore, while maintaining the degree of vacuum, Se alone was evaporated using the same resistance heating method to deposit 10μ of Se on the a-3e-Te layer.
A photoreceptor was obtained by stacking ma-5e layers.

〔Effect of the invention〕

The image forming medium of the present invention can easily convert information charges into visible information, and since the visible information is retained in the resin, it is extremely stable compared to media that accumulate charges. It can be stored in the form of analog information such as line drawings, images, (0,1) information, or digital information,
It is capable of storing high-quality, high-resolution information.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional diagram showing each aspect of the image forming medium of the present invention, FIG. 2 is a diagram for explaining the image forming method,
FIG. 3 is a diagram for explaining an electrostatic image recording method on a conventional image forming medium. 1 is a photoreceptor, 2 is a corona electrode, 3 is an image forming medium, 4 is a fine particle, 5 is a photoconductive layer support, 7 is a photoreceptor electrode, 9 is a photoconductive layer, 10 is an insulating layer, 11 is electrophoretic material layer, 12
13 is a thermoplastic resin layer, 13 is an electrode, 14 is a support, 15 is a power source, 16 is exposure light, and 17 is resistance heating. Figure 1 (b) Figure 2 Applicant Dai Nippon Printing Co., Ltd. Engraving of the drawings Figure 3 (b) (c) Procedural dispute formality (method) % formula % Name of the invention Image forming medium and image forming method 3゜Name of address related to the case of the person making the amendment

Claims (4)

[Claims] (1) An electrode is provided on a substrate, and a thermoplastic resin layer, an electrophoretic material layer or an electrochromic layer, and an insulating layer are sequentially laminated on the electrode, or an electrophoretic material is provided on the electrode. An image forming medium characterized in that a layer or an electrochromic layer and a thermoplastic resin layer are sequentially laminated, and the substrate, electrode, thermoplastic resin layer, and insulating layer are transparent or translucent. (2) The image forming medium according to claim 1, wherein the electrophoretic material layer is an ionizable dye layer. (3) The image forming medium according to claim 1, wherein the electrophoretic material layer is an ionized pigment layer. (4) A photoreceptor consisting of a photoconductive layer with an electrode provided on the front surface, a substrate provided on the rear surface, an electrode on the substrate, a thermoplastic resin layer, an electrophoretic material layer, or an electrochromic layer on the electrode. or an electrophoretic material layer or an electrochromic layer and a thermoplastic resin layer are sequentially laminated on the electrode, and the substrate, the electrode, the thermoplastic resin layer, and the insulating layer are laminated in sequence. an imaging medium that is transparent or translucent;
The photoconductive layer surface of the photoreceptor and the insulating layer surface of the image forming medium are placed facing each other in contact or non-contact, pattern exposure is performed while applying a voltage between both electrodes, and the image forming medium is thermally developed after exposure. Characteristic image forming method.