JPS62108087A - Recording material and device using said material - Google Patents

Abstract

PURPOSE:To enable writing by an electrical signal and enable additional recording also by an external thermal signal, by providing as one body a high molecular weight recording material comprising a conductive substance dispersed or dissolved in a high molecular weight material and electrodes. CONSTITUTION:Electrodes 51-5n are provided on a base 1 as back electrodes. A high molecular weight recording material layer 2 is provided thereon in a thickness of several micrometers to several hundred micrometers by mixing a transparent fine conductive powder. Transparent electrodes 41-4n are provided on the layer 2 substantially orthogonally to the back electrodes 51-5n in the form of stripes, thereby providing a matrix pattern of electrodes. When electric current are sequentially passed to intersection parts of the electrodes 4 and 5, an imagewise milky state is recorded in the recording material 2, and various images sent electrically are displayed on a display panel 10. In addition to electrical writing of images on the display panel 10, manual inputting can be performed by using a heat pen.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to materials and devices for arbitrarily recording and displaying electrical image signals, thermal signals, or hand-drawn images, and further relates to large-scale display devices and the like. The present invention relates to an erasable recording material that can also be applied to screen displays and a recording device using this material.

(Prior Art) Conventionally, it has been an old practice to record information such as images using a substance that changes its state within a short period of time when thermal energy is applied and the temperature rises above a certain level.

(Problems to be Solved by the Invention) Among these recording methods, photochromic substances,
Thermochromic materials, magnetic recording materials, etc. are known. Among the thermochromic substances, organic and
Various inorganic coloring materials are known, but like photochromy, they are difficult to fix. Recently, thermal recording materials that have replaced thermochromic materials include chalcogenides that utilize the phase change between crystalline and amorphous, low-molecular fatty acids, their amides, esters, etc. dissolved in glass or thermoplastic polymers. is a system using thermal material change of ammonium salt (Japanese Unexamined Patent Publication No. 5
7-117140) etc. have been proposed. However, chalcogenide glass is expensive and has the problem of toxicity because the recording material is produced by vapor deposition. Furthermore, films in which low-molecular substances are dissolved in thermoplastic polymers perform recording and erasing using slight temperature differences, and are currently not in practical use.

The present invention improves the drawbacks of the conventional recording materials described above, and provides a recording material that can be written to using electrical signals and additional recording can be performed using external thermal signals, and a recording device using this material. .

(Means for solving the problem) The recording material of the present invention changes from a transparent state to an opaque state by heating, and a conductive substance is dispersed or dissolved in a polymer that can fix the opaque state by controlling the cooling time after heating. This device integrally includes a polymeric recording body and an electrode that selectively energizes the polymeric recording body to cause the energized portion of the recording body to self-heat. Further, a recording apparatus using this recording material has a power supply control means for selectively supplying electricity to each electrode provided in the recording material, and is configured to visually check the image information of the recording material.

(Example) The polymer recording material applied to the recording material of the present invention is a thin layer made of a stable blend of two or more types of polymers, and is in a uniform phase arch state at a low temperature below a certain temperature. On the higher temperature side, the polymers are in a phase-separated state. If polymers with different light refractive indexes are used, the film will have uniform transparency in a compatible state, but will become opaque due to light scattering in a phase-separated state at high temperatures. The polymer blend system is of type LC3T (Lower cri
ticalSolution Temperature
) Combinations of several types of polymers are known as systems exhibiting a phase diagram.

For example, combinations of polyvinylidene heptadide and polymethyl acrylate, polyethyl acrylate, polymethyl methacrylate, polyethyl methacrylate, etc., and combinations of polycaprolactone and polycarbonate (R, E
, Bernstein et al.

Macromolecules 10 p681~(1
977) ) + polystyrene and polyvinyl methyl ether (M, Bank et, al.

J, Polym, Sci, + A-2, 10F10
97-(1972)).

Styrene-acrylonitrile copolymer and polycaprolact 7 (LP-McMaster, Macrm
olecules6 p760~(1973)),
Styrene-acrylonitrile copolymer and polymethyl methacrylate (L, P.

McMaster Polym Prepr, 15
p254-(1974)).

Polyvinyl nitrate and polymethyl acrylate (Sekiyama Sanbe,
et al., Polymer Papers 33 p238~ (1976))
.

Polyvinylidene heptanide and polyvinyl methyl ketone (D,
R, Paul et al., Polym En.
g Sci, 1891225~(1978))
, or ethylene-vinyl acetate copolymer and chlorinated rubber C
J, Leffingwell, et al.

Polym Prepr, , 14 p596~(1
973)) etc.

The combination of these polymers depends on the blend ratio, but
Heating to 100 to 200°C causes phase separation, and although there are differences in degree, light scattering is observed and the area becomes opaque compared to areas that are not heated.

Furthermore, the above-mentioned polymeric recording material can be fixed in a phase-separated state by rapidly cooling it from a heated phase-separated state, and when the fixed phase-separated state is heated again above the separation temperature and slowly cooled, the original phase can be restored. Return to molten state.

Therefore, the recording material of the present invention performs recording by applying a heating signal that exceeds the phase separation of the polymeric recording material and rapidly cooling it. or,
The recorded image is erased by completely intoxicating it or by heating the recorded part and slowly cooling it.

The present invention has further improved this polymeric recording material in order to achieve the above object. The improved recording material is made by dispersing and mixing conductive fine powder of carbon, tin oxide, etc. into the polymeric recording material described above to make the recording material a resistor.

FIGS. 1A and 1B show an example of a recording apparatus to which the polymeric recording medium 2 is applied, and the recording method thereof will be described below.

In this example, electrodes 51 to 5η of tin oxide, indium oxide, ITO, or the like are provided by vapor deposition or screen printing on the base 1 colored in black, green, or other colors to serve as back electrodes. On top of this, the polymer recording layer 2, which is formed by mixing mainly polyvinylidene fluoride, polymethyl acrylate, and transparent conductive fine powder such as tin oxide, is provided by printing or the like to a thickness of several micrometers to several hundred micrometers. Furthermore, polymer recording layer 2
Transparent electrodes 4□ to 4n made of ITO etc. are placed on the back electrode 5,
.about.5n in a stripe shape in a direction substantially perpendicular to .about.5n to form a matrix polar configuration.

In the figure, reference numeral 7 denotes a driver for the back electrodes 5 and -5η, and a driver 8 for electrodes 4□-4η. A power supply 9 selectively applies a voltage between the electrodes 4 and 5 to supply current. On the other hand, the polymer recording body 2 includes, for example, the electrode 4□ and the electrode 52.
At the intersection of these electrodes, when a voltage is applied between them,
Current flows in the thickness direction and generates self-heating due to Joule heat.

The voltage signal is sufficient to cause the polymer recording material to self-heat above the temperature required for phase separation as described above (e.g., 100°C to 200°C or higher), and this signal is pulse-like and sudden. In the case where 1 is removed under pressure, the exothermic portion, that is, the 41-5° intersection, is immediately assimilated (quenched) to the ambient temperature, and the cloudy state due to phase separation is maintained (memory).

As described above, by sequentially passing current through the intersections of the matrices 44 and 5 in accordance with the electrical signals, an image-like cloudy state is recorded on the polymer recording body 2, and the 4L gas is displayed on the display panel 10. The various images sent will be displayed.

The protection MIvj3 for protecting the polymeric recording medium 2-F6 and the plate 4 in FIG. 1 is a coating of Teflon, silicone resin, or other fluororesin.

It can be obtained by laminating or the like, but it may be provided as necessary.

In the present invention, in addition to electrical image writing on the display panel 10 as described above, handwritten input using the thermal pen 6 is possible. If the thermal pen uses a laser, the laser energy absorption effect is provided by the colored substrate 1, or an absorption layer or absorption pigment (not shown) is applied to the substrate 1.
The function of heating the polymeric recording material 2 can be provided by providing it in a layer or further dispersing it in the polymeric recording material 2.

Next, the image recorded in the above manner can be erased by the following example.

First, when erasing the entire screen, apply current to all electrodes 41 to 4η or electrodes 5□ to 5t-+, one or both of them independently, heating the entire surface to make it cloudy, and then applying the current amount By gradually decreasing the amount, the entire surface can be slowly cooled and the above-mentioned uniform miscible state can be achieved. This is because if the electrodes 4 or 5 are made of a material having a suitable resistance such as ITO, the electrodes themselves become heaters.

Alternatively, by creating a uniform potential difference between all electrodes 4□ to 4n and electrodes 5 and 5η, all intersections are energized to generate heat, become cloudy, and then gradually cooled down by gradually dissipating the potential difference. The above-mentioned compatible state can be made uniform.

In any of the above erasing methods, the power source used may be different from the power source for image writing.

When partially erasing a recorded image, after an operation for specifying an erasure area (not shown) is performed, electricity is applied to the electrode joining part only in the specified area in the same way as in the recording, to heat the pixels in the area. However, in this case, the applied voltage signal is not pulse-like (the fall time is lengthened), or the pixels in the erase area are repeatedly energized several times in sequence, and the voltage before each energization is gradually decreased. In these cases, the erasing time may be increased if necessary. Erasing can also be accomplished by manually applying a controlled heating and slow cooling means to the front surface of the pond or panel.

FIGS. 2A-2B show a schematic diagram of a recording apparatus to which the above recording method is applied. The blackboard type and tablet type are shown here. As an electric image signal source, signals stored in a facsimile No. 1ε, a floppy disk, or an optical (magnetic) disk can be converted by a known method and input into the recording apparatus of the present invention.

Figures 3A-B-C are another embodiment-example according to the present invention.

The recording material shown in the figure is a transparent sheet 11 made of polyethylene terephthalate or the like, a transparent conductive layer 12 made of ITO or the like, and a rotatable sheet 20 in which the polymer recording material 2 and the protective layer 13 are integrated.
form. However, the transparent conductive layer 12 is insulated from each other in each area forming one screen.

In this example, a continuous head 15 in the form of a 2iC array in a polymeric recording medium is used.
An image is recorded using an external signal, and handwritten input is performed using an energized pen 14. colored board 17
also serves as a platen template when handwriting is recorded using the energized pen 14.

First, recording an image on the digital camera 20 using an external electrical signal will be described. When an electric signal is sent from the outside, the sheet 20 is sent in the direction of the arrow by the rotation of the drive roller 18. Immediately after this, a voltage is selectively applied to the RAD array 15Vc to the energized device that is holding the sheet 20 and is pressed against the platen 16 (or platen roller 16), and energization is started to the polymer recording body 2 in the same manner as described above. An image is formed on the sheet as the sheet 20 moves. When one screen has been recorded, the drive roller 18
stops, and the recorded image is displayed still. Furthermore, handwritten input can be performed using the energized pen 14.

Next, the image is erased by heating the transparent conductive αJ*12 by flowing a 1E current, and by gradually decreasing the ammeter, the image is gradually cooled, and as described above, the transparent conductive layer is If they are divided, the entire screen is erased. It is convenient for the use of the apparatus to perform this erasure when the recorded image is not displayed, that is, when it is located on the back side of the display section 2. Or 22 in the diagram
As shown in the figure, a surface heater may be provided in the device to perform heating and slow cooling for erasing.

Here, the protective layer 13 in FIGS. 3A-B-C is used to prevent the polymer recording body 2 from being damaged due to contact of the electronic pen or the rad array with a current-carrying object, but in order to realize the apparatus of the present invention, is not necessarily necessary. protection, 1ifl
13 is Teflon resin, for example.

By mixing conductive fine particles with silicone resin, fluorine resin, etc., the resistance value in the thickness direction is made to be approximately the same as or slightly higher than the resistance value in the thickness direction of the polymer resistor 2 used. By the way, this protection! Deterioration in resolution due to the addition of the II layer 13 can be reduced.

The protective layer 13 may be electrically insulating as long as it is a sufficiently thin layer. In this case, recording equivalent to one stroke with an energized pen or an energized head array is performed by using a moderately high-frequency alternating current pulsating current. , it is possible to generate heat that causes the substantially polymeric recording medium 2 to perform recording.

By the way, also in the recording device shown in this example, the heating and slow cooling means adjusted as the partial erasing means can be manually operated from the display surface side.
Or it can be granted automatically.

(Effects of the Invention) As explained above, according to the present invention, it is possible to record and display on a large area, and furthermore, it is difficult to configure the heating means when performing thermally erasable recording using an external electric signal. Since a recording signal can be applied even with a simple electrode configuration, it is possible to apply the present invention to display devices for various purposes.

[Brief explanation of drawings]

FIG. 1A is a sectional view of a display device using the display member of the present invention, FIG. 1B is an explanatory diagram explaining the display principle, FIGS. 2A and 2B are a side view showing the form of the display device, and FIG. 3A 3B is an explanatory diagram of the layer structure of the recording material, and FIG. 3C is a plan view of the recording section. In the figure, 1 is a colored substrate, 2 is a polymeric recording material, 4...
4η・5, ~5. n is an electrode, 7.8 is a driver, 9 is a power supply, 11 is a transparent sheet, 12 is a transparent conductive layer,
13 indicates a protective layer. Patent Applicant: Canon Co., Ltd. No. 3 Fuguan 3BfZJ No. 3C Diagram

Claims (1)

[Scope of Claims] 1. A polymeric recording material in which a conductive substance is dispersed or dissolved in a polymeric material that changes from a transparent state to an opaque state by heating and can be fixed in an opaque state by controlling the cooling time after heating;
A recording material characterized by having an electrode that causes a current-carrying portion of the recording body to self-heat by selectively energizing the polymeric recording body. 2. A polymeric recording material in which a conductive substance is dispersed or dissolved in a polymeric material that changes from a transparent state to an opaque state by heating and can be fixed in an opaque state by controlling the cooling time after heating;
an electrode that selectively energizes the polymeric recording body to self-heat the energized portion of the recording body;
A recording device comprising: a power source that selectively applies a voltage to the electrodes.