JPH08320463A - Information reproducing/erasing device - Google Patents

Abstract

PURPOSE: To effectively and surely erase information recorded instantly after reproduced by respectively constituting specified information reproducing means and heat erasing means. CONSTITUTION: A recording film 216 is irradiated by lighting light with a selected suitable wavelength in an optical system consisting of a light source 70, an IR cut filter 71, a band-pass filter 72 and a lens 74. The transmission light of the film 216 is adjusted so as to image form on a CCD line sensor 75 by the image forming lens 74. The sensor 75 is set up on a movable stage, and the stage is controlled by a stepping motor, and the information is reproduced by converting the transmission light to an electric signal by the sensor 75 matching with the movement of the stage. When the information is reproduced, the recording part is moved to an information erasing part by a roller 213. The erasure means that a part of an oriented liquid crystal transmitting through light is eliminated by heating a liquid crystal layer 106 to a prescribed temp., and the whole is made the state scattering light.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an information reproducing device,
In particular, the present invention relates to an information reproducing / erasing apparatus which erases information recorded on a liquid crystal recording medium having a polymer dispersed liquid crystal layer or a polymer-liquid crystal composite layer immediately after reproducing.

[0002]

2. Description of the Related Art Conventionally, an information recording medium having a polymer dispersed liquid crystal layer formed on an electrode and an optical sensor having a photoconductive layer formed on the electrode layer are arranged so as to face each other, and an image is recorded by voltage application exposure. Those disclosed in JP-A 6-130347 and JP-A 5-130347
No. 165005, Japanese Patent Application No. 5-17 relating to the applicant's application
3988. In addition, an information recording medium having a polymer-liquid crystal complex formed on an electrode and a photosensor having a photoconductive layer formed on an electrode layer are arranged so as to face each other, and image recording is performed by voltage application exposure. 4-362916
No. FIG. 1 is a diagram showing the configuration of an information recording apparatus using such an information recording medium. 10 in the figure
Is an optical sensor, and 20 is an information recording medium. The optical sensor 10 includes a transparent electrode 12 on a transparent support 11,
The photoconductive layer 13 is sequentially laminated, and the information recording medium 20 has a transparent electrode 22 and a polymer dispersed liquid crystal layer 23 on a transparent support 21.
Are sequentially laminated, and a skin layer 24 is formed on the surface of the liquid crystal layer. The photoconductive layer 13 has a single layer structure such as amorphous selenium or amorphous silicon as an inorganic photoconductive layer, polyvinylcarbazole to which trinitrofluorenone is added as an organic photoconductive layer, or polyvinyl butyral as an azo pigment as a charge generation layer. It is possible to use, for example, a layer in which a charge dispersion layer is dispersed in a resin such as the above and a layer in which a hydrazone derivative is mixed with a resin such as a polycarbonate as a charge transfer layer are laminated.

For the information recording layer 23 of the information recording medium 20, a polymer-liquid crystal composite, polymer dispersed liquid crystal or the like can be used. In the polymer-liquid crystal complex, for example, liquid crystal and resin are mixed and dissolved in a common solvent, the solution is applied by a spinner or the like, and then the solvent is evaporated and dried, whereby the liquid crystal phase and the resin phase are phase-separated. It is known that a liquid crystal phase and a resin phase are separated from each other by taking a structure in which the liquid crystal phase is dispersed in the resin phase. Further, the polymer-dispersed liquid crystal is, for example, dried at a temperature at which a mixture of liquid crystal and a monomer of an ultraviolet curable resin becomes an isotropic phase, and in a state where the liquid crystal phase and the resin phase are separated, ultraviolet rays are irradiated to polymerize the monomer. It is known that the liquid crystal phase and the resin phase can be produced by making the resin phase dispersed in the liquid crystal phase. The circles in the figure represent polymer balls dispersed in the liquid crystal layer. Before the information is recorded, the alignment direction of the liquid crystal randomly scatters light, and when the information is recorded, the alignment direction of the liquid crystal is partially aligned and the light is transmitted. When a smectic liquid crystal having a memory property is used as the liquid crystal, the alignment state is maintained even if the electric field is removed after the liquid crystal is aligned by applying an electric field, and this recording state is stable and has a long-term memory property. The alignment state can be returned to the non-alignment state by heating to a temperature at which the liquid crystal phase becomes an isotropic phase and then cooling.

A type in which the optical sensor and the information recording medium as shown in FIG. 1 are opposed to each other with a space of about 10 μm using a spacer such as polyethylene or polyimide, and exposed by voltage application, and FIG. A structure in which an optical sensor and an information recording medium are laminated as shown in FIGS. 2A and 2B has also been proposed. In a laminated recording medium, information is recorded on the optical sensor as shown in FIG. 2A. As shown in FIG. 2B, the recording phase is directly laminated and the transparent dielectric intermediate phase 2 is used.
There are some which intervene 5. Such an optical sensor 10
When the information recording medium 20 and the information recording medium 20 are opposed to each other and a voltage is applied between the electrodes 12 and 22 by a power source 30 as shown in FIG. 3 and visible light is irradiated as writing light, the photoconductive layer 13 of the photoconductive layer 13 is irradiated in accordance with the exposure intensity. The conductivity changes, the electric field applied to the liquid crystal layer 23 changes, the alignment state of the liquid crystal changes, and the applied voltage is turned off.
Then, the state is maintained even after the electric field is removed, and the exposure information is recorded.

To reproduce the recorded exposure information, for example, as shown in FIG. 4, the information recording medium 20 is irradiated with reproduction light by a power source, and the transmitted light is read by the photoelectric conversion device 60 and converted into an electric signal. It is done by Light source 40
As the reading light, a white light source such as a xenon lamp or a halogen lamp or laser light is used, and as the reading light with which the liquid crystal recording medium is irradiated, it is desirable to select and irradiate light with an appropriate wavelength by the filter 50. The incident light is modulated according to the alignment state of the liquid crystal of the information recording medium, the transmitted light is converted into an electric signal by the photoelectric conversion device 60 including a photodiode, etc., and the converted electric signal is converted into a printer or a CRT if necessary. Is output to. Further, the details of the reproducing apparatus are described in Japanese Patent Application No. 7-36908 and Japanese Patent Application No.
No. 219744.

The information recorded on the information recording medium can be converted into an electric signal by a reproducing apparatus as shown in FIG. In FIG. 5, a light source 70 and an IR cut filter 7
The illuminating light whose proper wavelength is selected by the optical system including the bandpass filter 72 and the lens 74 is the information recording medium 20.
Is irradiated. The transmitted light of the information recording medium is formed by the imaging lens 7
5 is adjusted so that an image is formed on the CCD line sensor 75. The information recording medium is installed on a movable stage (not shown), and the stage is controlled by a stepping motor, and the transmitted light is transferred to the CCD as the stage moves.
Information is reproduced by converting it into an electric signal by the sensor.

[0007]

An information recording medium using a polymer-dispersed liquid crystal or a polymer-liquid crystal composite has a very high information memory property. When information is recorded, it is semipermanent under certain conditions. No information is lost to. On the other hand, due to its high memory performance, once the memory is stored, if it is left as it is for a long time, even if it is attempted to remove the recorded information, the erasure will be incomplete and some recorded information will remain, and the recorded information will not be recorded. In some cases, it may remain as an afterimage. Therefore, when recording is performed once and the information recording medium is to be used again, it is preferable to erase the recorded information immediately after reproducing the information. However, in the information reproducing apparatus up to now, there is only a function of reproducing the information, and it is difficult to erase the information immediately after the reproduction. In such an information reproducing method, the information recorded immediately after the reproduction is recorded. There has been a demand for an efficient and reliable erasing method.

The present invention is an information reproducing means capable of reproducing information recorded on an information recording medium having a polymer dispersed liquid crystal layer or a polymer-liquid crystal composite layer, and information capable of erasing information. It is an object of the present invention to provide an information reproducing / erasing apparatus including an erasing unit.

[0009]

The present invention reproduces information recorded on an information recording medium comprising a support, a transparent electrode, a polymer-dispersed liquid crystal layer or a polymer-liquid crystal composite layer, which are sequentially laminated. It is characterized by comprising information reproducing means and heat erasing means for erasing the information recorded on the information recording medium by heating the information recording medium to a predetermined temperature. The present invention also provides a liquid crystal on an information recording medium comprising a support, a lower transparent electrode, a polymer-dispersed liquid crystal layer or a polymer-liquid crystal composite layer, a dielectric layer, a photoconductive layer, and an upper transparent electrode, which are sequentially laminated. Information reproducing means for reproducing recorded information by orienting the information recording medium, and heating erasing means for erasing the information recorded on the information recording medium by heating the information recording medium to a predetermined temperature. Characterize. Further, the present invention is characterized in that the information recording medium heated to a predetermined temperature by the heat erasing means is further provided with an electric field applying erasing means for erasing an image by further applying an electric field.

[0010]

The information reproducing / erasing apparatus of the present invention handles reproduction and erasing of information recorded on an information recording medium in which a polymer dispersion type liquid crystal layer or a polymer-liquid crystal composite layer and a transparent electrode are laminated. . The above information recording medium has a strong memory property, and if the information is recorded as it is, the recorded information cannot be completely erased, and some of the information is not erased. It is left on the medium, making repeated use difficult. According to the information reproducing / erasing apparatus of the present invention, the information recorded as a light-scattering image on the information recording medium is optically read, and immediately after the necessary information is stored as digital data, the information is erased on the information recording medium by the heat erasing means. The recorded information is erased by heating the information recording medium to a predetermined temperature, or the information recording medium is heated to a predetermined temperature before erasing the information recorded on the information recording medium by a heating means, Since the electric field is applied to the information recording medium by the electric field erasing means to erase the image, the information recording medium can be repeatedly used.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The information reproducing / erasing apparatus of the present invention will be described below in detail with reference to the preferred embodiments. FIG. 6A is a perspective view showing the structure of the information reproducing / erasing apparatus of the present invention having a heat erasing section, and FIG. 6B is a view showing the layer structure of the recording film. In FIG. 6, reference numeral 216 is a recording film which is a winding body. Regarding the layer structure of the recording film 216, 101 is a first substrate, 102 is a first transparent electrode, 103 is a photoconductive layer, the photosensor 107 is composed of these, and 105 is a second transparent electrode. , 106
Is a liquid crystal layer, the information recording medium 108 is composed of these, and the optical sensor 107 and the information recording medium 108 are integrated with each other with the dielectric layer 200 interposed therebetween. Of course, the optical sensor and the information recording medium may be of a separable type, and the recording film may be composed of only the information recording medium.

The information reproducing section irradiates the recording film 216 with illumination light of an appropriate wavelength selected by an optical system including a light source 70, an IR cut filter 71, a bandpass filter 72 and a lens 74. The light transmitted through the recording film is transferred to the CCD line sensor 7 by the imaging lens 74.
5 is adjusted to form an image. In FIG. 6A, reference numeral 212 is a first roller, which is a heating roller having a heater inside. Reference numeral 213 denotes a second roller, which is configured to sandwich the recording film 216 together with the first roller and to be rotatable. Reference numeral 214 denotes a heater power supply, which supplies electric power to the first roller.

Next, the operation will be described. The recording film 216 of the winding body is supplied from the supply side (upper side in the drawing) and intermittently transferred to the winding side (lower side in the drawing). As shown in the figure, the recording film 2 is provided on the downstream side of the information reproducing section of the transfer path.
16 is sandwiched between the first roller and the second roller,
By rotating these rollers, the recording film 2
16 is transported, and after being transported a predetermined distance, the rotation of these rollers is stopped and the recording film 216 is also stopped. In this transfer, the recording film 216 is provided on the winding side.
The torque that rotates in the direction of winding is applied, and the recording film 216 corresponding to the transported distance is wound. The first roller 212 has a heat generator (not shown) inside as described above. As the heating device, a heating resistor such as a nichrome wire, ceramic, or a semiconductor, an induction heating device, or the like can be used. Electric power is supplied from the heater power supply 214 to this heat generator to heat the first roller 212, and a temperature control device (not shown) adjusts the electric power supplied from the heater power supply 214 based on the output signal thereof. Further, the temperature control device stops the supply of electric power or reduces the supply amount of electric power in the state where the transfer is stopped, and sets the preheated state.

The heat erasing section in the present invention comprises a first roller 212, a second roller 213, a heater power supply 214, a temperature sensor, a temperature control device and the like. Recording film 21
6 is the first roller 212 and the second roller 2 as described above.
While being sandwiched by 13 and transferred, it is heated to a predetermined temperature. The recording film 216 used in the present invention has a characteristic that recorded information is erased when heated to a predetermined temperature. As the information recording layer of the recording film 216, a polymer dispersed liquid crystal layer (or polymer-liquid crystal composite layer) 106 is used. For example, a polymer-dispersed liquid crystal has a structure in which a resin is dispersed in a liquid crystal layer, and the orientation direction of the liquid crystal is random before information is recorded, so light is scattered and information is When recorded, the alignment direction of the liquid crystal is partially aligned and light is transmitted. Information is recorded in the liquid crystal layer as a pattern that partially scatters light and partially transmits light.

The recorded information is converted into an electric signal by the reproducing section and reproduced. In FIG. 6, a light source 70, an IR cut filter 71, a bandpass filter 72, a lens 7
The information recording medium 20 is irradiated with illumination light having an appropriate wavelength selected by the optical system of 4. The transmitted light of the information recording medium is adjusted by the imaging lens 75 so as to form an image on the CCD line sensor 75. The CCD line sensor is installed on a movable stage (not shown), the stage is controlled by a stepping motor, and the transmitted light is converted into an electric signal by the CCD sensor in accordance with the movement of the stage to reproduce information. . When the information reproduction is completed, the recording portion is moved to the information erasing portion by the roller.
Erasure is to heat the liquid crystal layer 106 to a predetermined temperature to eliminate the oriented liquid crystal portion that transmits light and to make the entire state of scattering light. The recording film 216 from which the recording has been erased is finally wound and can be repeatedly used.

Next, another embodiment of the present invention will be described. FIG. 7A is a perspective view showing the structure of the information reproducing / erasing apparatus of the present invention having an electric field erasing section, and FIG. 7B is a view showing the layer structure of the recording film. The same parts as those in FIG. 6 are designated by the same reference numerals (the same parts are designated by the same reference numerals in the drawings related to the present invention). In FIG. 7, 217 is different from the erasing mechanism in FIG.
The electric field generator and the voltage source 218 are provided. In addition, the recording film 216 does not have the optical sensor 107, and as shown in FIG.
The information recording medium 108 itself is composed of a second transparent electrode 105 and a liquid crystal layer 106. The layer structure of the recording film 108 is not particularly related to the erasing mechanism, and may be an integrated type in which an optical sensor and an information recording medium are laminated as in the case of FIG. In FIG. 7, when the electric field generator 217 is not used, the operation is similar to that in FIG. The electric field generator 217 is an electrode having a bar-shaped structure, and is connected to one terminal of the voltage source 218. The other terminal of the voltage source 218 is connected to the second transparent electrode 105 of the recording film. Therefore, the voltage generated by the voltage source 218 generates an electric field almost perpendicular to the surface of the liquid crystal layer 106 which is the information recording layer between the electric field generator 217 and the transparent electrode 105.

The electric field erasing section in the present invention comprises an electric field generator 217, a voltage source 218, a first roller 212, a second roller 213, a heater power supply 214, a temperature sensor, a temperature control device and the like. Similar to the case of FIG. 6, the recording film 216 is transferred by the first roller 212 and the second roller 213 for information erasing after information reproduction, and heated to a predetermined temperature. At this time, the recording film 216 is in a light scattering state. When it is further transferred in this state and reaches below the electric field generator 217, the liquid crystal layer 106 of the recording film 216 is aligned by the electric field. At this time, the recording film 216 changes to a light transmitting state. When the liquid crystal layer 10 is further transferred and leaves under the electric field generator 217 and goes out of the electric field,
Since 6 is just after heating, it becomes a random arrangement again and becomes a light scattering state. As described above, according to the electric field eraser of FIG.
The process of aligning the liquid crystal layer 106 is included, and the erasing ability is extremely high and the afterimage disappears.

By the way, in the above, the recording film 2
The temperature of 16 is a temperature at which recorded information is erased when the recording film 216 leaves under the electric field generator 217 and goes out of the electric field, and reaches a temperature having a memory function when the information is recorded. It is a necessary condition to be lowered. By changing the temperature condition, the front surface of the recording film 216 can be made transparent and the transparent state can be maintained. That is, if the recording film 216 is set under conditions such that the temperature of the recording film 216 reaches a temperature having a memory function while the recording film 216 reaches below the electric field generator 217 and enters the electric field, It can be kept transparent. The recording film 216 thus maintained in a transparent state can be used in a case where information is recorded by making a portion to which heat is applied in an opaque state by giving a predetermined heat pattern by a thermal head or the like.

FIG. 8 is a view for explaining a modification of the erasing mechanism in the information reproducing / erasing apparatus of the present invention. In FIG. 8A, a planar heating element 219 is provided in contact with the recording film 216 so that the recording film 216 can be transferred. As the planar heating element 219, a planar heating element having a heating resistor such as a nichrome wire, an aluminum thin film or the like patterned in a planar shape, a transparent heating element coating such as an ITO coating, a coating containing a conductive substance such as carbon, etc. Can be used. FIG.
In (a), after reproducing the information from the recording film 216,
It is necessary to heat above the erasing temperature and cool. Therefore, the sheet heating element 219 is not heated by the recording film 216 after heating.
It is preferable to be configured to stand by at a position distant from or to reduce the heat capacity so as to improve the response to heat. Further, it is effective to use a cooling means such as a blower fan together.

FIG. 8 (b) shows a linear heating element. Regarding cooling after heating, which is a problem in the planar heating element of FIG. 8A, the efficiency of cooling is greatly improved by making the heating element a line, and a special mechanism can be omitted. However, conversely, since the heating efficiency may decrease, it is preferable that the linear heating element 220 has a rod-like shape having a certain area rather than a thin linear shape.

FIG. 8 (c) shows a head-shaped heating element. By making the heating element a head shape,
The area of the heating element is reduced, resulting in improved heat problems and cost benefits. However, in order to heat the entire recording medium due to the head shape, it is necessary to scan the head in the direction perpendicular to the medium feeding direction, and at that time, by intermittently feeding the recording medium, head-shaped heat generation Sufficient heating by the body 221 is possible.

FIG. 8D is a diagram showing a structure in which the terminals of the voltage source 218 are directly connected to the first transparent electrode 102 and the second transparent electrode 105 in the recording film 216 having the layer structure shown in FIG. is there. In this case, the electric field causes the liquid crystal layer to align and become transparent so that the image is erased.

FIG. 9 shows a modification of the heating erasing section or heating means, which is a diagram showing a structure using dielectric heating. In FIG. 9, 230 is a high frequency power supply, 231 is a high frequency oscillator,
232 is an electromagnetic shielding container. In FIG. 9 (a),
In the recording film 216 having the layer structure shown in FIG. 6, the output terminal of the high frequency power source 230 is directly connected to the first transparent electrode 102 and the second transparent electrode 105, and the recording film 216 made of a dielectric material is heated by dielectric heating. To do. In addition, FIG.
In (b), the recording film 216 is installed in the electromagnetic shielding container 232, or the recording film 216 is so arranged as to pass through the electromagnetic shielding container 232 in the transfer path (the electromagnetic shielding container 232 is provided with a slightly opened entrance and exit). ), The microwave oscillated from the high frequency oscillator 231 provided in the electromagnetic shielding container 232 is radiated to the recording film 216 made of a dielectric material to dielectrically heat it.

FIG. 10 is a diagram showing another modification of the erasing mechanism in the information reproducing / erasing apparatus of the present invention. Figure 10 (a)
Is obtained by heating the heating element shown in FIG. 6 with laser spot light. The beam output from the laser 240 is a lens 242, a mirror 241, and a lens 24.
It is guided onto the information recording medium 216 by an appropriate spot shape, intensity, and optical path via an optical system including 3 or the like. By irradiating the information recording medium with a strong laser spot light, a sufficient erasing temperature is generated in the information recording medium in a short time. However, by making the spot shape, in order to heat the entire recording medium, it is necessary to scan the laser light in a direction perpendicular to the medium feeding direction, and at that time, by intermittently feeding the recording medium, As in the case of the head-shaped heating element, sufficient heating is possible.

FIG. 10 (b) shows that the heating by the laser spot light in FIG. 10 (a) is changed to a linear laser light by an optical system. The line-shaped laser light is guided onto the information recording medium by the optical systems 244 and 245 that extract only in one direction, with an appropriate line shape, intensity, and optical path. By making the laser beam linear,
There is no need for laser beam scanning or intermittent feeding of the information recording medium as in (a). However, since the laser has a line shape, the intensity of the laser may decrease and sufficient heating may not be possible. Therefore, it is necessary to use a sufficiently strong laser light source as the light source.

FIG. 11 is a diagram showing a modification of the information recording medium in the information reproducing / erasing apparatus of the present invention. Figure 11
In (a), the medium is in the form of a card, the information recording medium is directly driven by a roller, and the erasing device is a planar heating element 251, as in FIG. 8 (a). The driving method is basically the same as that of the recording film, except that the card-shaped medium 250 is reciprocated by rollers. Similarly, in FIG. 11B, the recording medium is a card shape, and the erasing device is a planar heating element 251. The recording medium is set on a fixing jig 252, and a medium 250 is driven together with the fixing jig by a ball screw type driving device 253. In both FIGS. 11A and 11B, a planar heating element is used as the heating element, but it goes without saying that various heating methods described above can be used.

FIG. 12 is a diagram showing another modification of the information recording medium in the information reproducing / erasing apparatus of the present invention. In FIG. 12, the recording medium is disk-shaped, and the disk-shaped medium 260 rotates around the center. Although the sheet heating element 261 is shown as the heating element here as well, it goes without saying that the above-described various heating methods other than that can be used. Although the examples have been shown above in the form of recording film type, the substrate is something other than a film, for example, a glass substrate,
It goes without saying that the same thing can be done with a plastic substrate.

[Structure and Material of Optical Sensor] First, the optical sensor will be described. The photosensor includes a charge generation layer and a charge transport layer, and the charge generation layer includes a charge generation material and a binder. Examples of the charge generating substance include pyrylium dyes, azurenium dyes, squarylium salt dyes, phthalocyanine pigments, perylene pigments, polycyclic quinone pigments, indigo pigments, pyrrole pigments, azo pigments, and other dyes and pigments. Can be used alone or in combination. Examples of the binder include polycarbonate resin, vinyl formal resin, vinyl acetal resin, vinyl butyral resin, polyester resin, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin and the like. The binder resins may be used alone or in combination of two or more. Regarding the mixing ratio of these charge generating agent and binder, it is desirable to use the binder in an amount of 0.1 to 10 parts by weight, preferably 0.2 to 1 part by weight, relative to 1 part by weight of the charge generating agent. The thickness of the charge generation layer after drying is 0.01 to 1 μm.
And preferably 0.1 to 0.5 μm,
With such a film thickness, good sensitivity and image quality are exhibited. In addition, the above-described charge-generating substance that can be vapor-deposited can also be formed alone without using a binder.

The charge transport layer comprises a charge transport material and a binder. The charge-transporting substance is a substance having a good property of transporting charges generated in the charge-generating layer, and includes, for example, oxazole-based, thiazole-based, triphenylmethane-based, styryl-based, stilbene-based, hydrazone-based, carbazole-based, enamine-based, aromatic compounds. There are group amine-based, triphenylamine-based, butadiene-based, polycyclic aromatic compound-based, biphenyl-based, and the like, and it is necessary to use substances having good hole transport properties. As the binder, the same as the binder in the charge generation layer described above, further styrene resin, styrene-butadiene copolymer resin, polyarylate resin, phenoxy resin can be used, but preferably styrene resin styrene-butadiene copolymer resin, It is a polycarbonate resin. The binder is used in an amount of 0.1 to 10 parts by weight, preferably 0.1 to 1 part by weight, based on 1 part by weight of the charge transport material. The thickness of the charge transport layer after drying is 1 to 50 μm, preferably 3 to 26 μm.
It is preferable that the film thickness be such that good sensitivity and image quality can be obtained.

[0030] Although the first transparent electrode 102 is the information recording medium is required to have transparency as long as opaque, transparent if the information recording medium has a transparency may be either opaque, 10 ⁶ Ω · cm Materials that stably provide the following specific resistance, for example, metal thin film conductive films of gold, platinum, zinc, titanium, copper, iron, tin, tin oxide, indium oxide, zinc oxide, titanium oxide, tungsten oxide, vanadium oxide, etc. These metal oxide conductive films, organic conductive films such as quaternary ammonium salts, etc. can be used alone or as a composite material of two or more kinds. Of these, oxide conductors are preferable, and indium tin oxide (ITO) is particularly preferable. First transparent electrode 1
02 is vapor deposition, sputtering, CVD, coating,
It is formed by a method such as plating, dipping, and electric field polymerization. In addition, the film thickness depends on the electrical characteristics of the material forming the electrode,
It is necessary to change the voltage depending on the applied voltage at the time of information recording. For example, an ITO film has a thickness of about 10 to 300 nm, which is formed in front of the information recording layer or according to an arbitrary pattern. Further, two or more kinds of materials can be laminated and used.

The first substrate 101 is required to have transparency if the information recording medium described later is opaque.
When the information recording medium has transparency, it may be transparent or opaque and has a shape of a card, a film, a tape, a sheet, a disk, etc., and strongly supports the optical sensor. For example, flexible plastic film, glass, polyethylene, polypropylene,
Rigid bodies such as polyethylene terephthalate, polymethyl methacrylate, polymethyl acrylate, polyester, polycarbonate, and other plastic sheets and cards are used. If the electrode 102 is transparent, a layer having an antireflection effect is laminated on the other surface of the substrate on which the electrode 102 is provided, or a film having a film thickness capable of exhibiting the antireflection effect is formed. The antireflection property may be imparted by adjusting the transparent substrate or by combining the two.

[Manufacturing of Stacked Photosensor] Next, a method of manufacturing the stacked photosensor will be described. An ITO film having a sheet resistance of 80 Ω / □ and a film thickness of 100 nm was formed by sputtering on a sufficiently washed glass substrate having a thickness of 1.1 mm to obtain an electrode. The electrode was sufficiently washed by a scriber washing machine, and 3 parts by weight of a bisazo pigment having a structure represented by the following [Chemical formula 1] as a charge generating substance on the electrode,
Vinyl chloride-vinyl acetate mixed resin (Denka vinyl # 1000D manufactured by Denki Kagaku Kogyo and Aldrich 18,
325.89J (75:25 mixture with vinyl acetate resin) 1 part by weight is mixed with 98 parts by weight of 1,4-dioxane and 98 parts by weight of cyclohexanone, and sufficiently kneaded with a mixer to prepare a coating solution, which is a spinner. At 1400 rp
m, 0.4 seconds.

[0033]

Embedded image

Then, a film is formed on the surface of the coating film,
It is left in a dust-free state for leveling drying until the surface does not adhere, and then dried at 100 ° C for 1 hour to obtain a film thickness of 3
A 00 nm charge generation layer was laminated.

On the charge generation layer, 50 parts by weight of a butadiene dielectric (T-405 manufactured by Anan) having a structure represented by the following formula [Chemical formula 2] as a charge transport material and a styrene-butadiene copolymer resin (manufactured by Denki Kagaku Kogyo) Clearlen 730L) 1
0 parts by weight and 68 parts by weight of chlorobenzene, 1,1,2-
A coating solution was prepared by uniformly dissolving 136 parts by weight of trichloroethane.

[0036]

Embedded image

Using the coating solution, a spinner was used for 350
Coating at rpm for 0.4 seconds, until a film is formed on the surface of the coating film and the surface of the coating film does not adhere,
After leaving it under no wind and performing leveling drying, 80 ℃ 2
After drying for an hour, a charge transport layer is laminated, and an optical sensor of the present invention having a photoconductive layer having a film thickness of 20 μm composed of a charge generation layer and a charge transport layer is produced. Aged for a day.

[Structure and Material of Information Recording Medium] Next, the structure and material of the information recording medium 108 will be described. First, as an information recording medium in the present invention, a case where the information recording layer is a polymer dispersed liquid crystal is mentioned. The polymer-dispersed liquid crystal has a structure in which resin particles are dispersed in the liquid crystal, but the liquid crystal material may be a smectic liquid crystal, a nematic liquid crystal, a cholesteric liquid crystal, or a mixture thereof. As the liquid crystal, it is preferable to use a smectic liquid crystal from the viewpoint of so-called memory property that retains its orientation and permanently retains information.
As the smectic liquid crystal, a liquid crystal substance exhibiting a smectic A phase such as a cyanobiphenyl type, a cyanoterphenyl type, a phenyl ester type having a long terminal carbon group of a substance exhibiting liquid crystallinity, a fluorine type or the like is used as a ferroelectric liquid crystal. Examples thereof include a liquid crystal substance exhibiting a smectic C phase, a liquid crystal substance exhibiting smectic H, G, E, F and the like.

The material for forming the resin particles is, for example, an ultraviolet curable resin which is compatible with the liquid crystal material in the monomer or oligomer state, or a solvent which is common to the liquid crystal material in the monomer or oligomer state. Those having compatibility with can be preferably used. Examples of such an ultraviolet curable resin include acrylic acid ester and methacrylic acid ester. In addition, a solvent-soluble thermosetting resin having compatibility with a liquid crystal material and a common solvent, for example, an acrylic resin, a methacrylic resin, a polyester resin, a polystyrene resin, and a copolymer containing these as a main component, an epoxy resin, You may use silicone resin etc. The ratio of the liquid crystal material and the resin used is such that the liquid crystal content is 10 to 90 parts by weight, preferably 40 parts by weight.
It is recommended to use it in an amount of up to 80% by weight.
When the content is less than 10 parts by weight, the light transmittance is low even if the liquid crystal phase is oriented by information recording, and when it exceeds 90% by weight, a phenomenon such as exudation of liquid crystal occurs and image unevenness is not preferable.
Since the film thickness of the information recording phase affects the resolution, the film thickness after drying is 0.1 μm to 10 μm, preferably 3 μm to 8 μm.
Therefore, the operating voltage can be lowered while maintaining the high resolution. If the film thickness is too thin, the contrast of the information recording portion will be low, and if it is too thick, the operating voltage will be high, which is not preferable.

[Production of Information Recording Medium] Next, a method for producing the information recording medium will be described. An ITO film having a thickness of 100 nm was formed as a conductive layer on a glass substrate having a thickness of 1.1 mm by sputtering to obtain an electrode, and then the surface was washed. A polyfunctional monomer (dipentaerythritol hexaacrylate, manufactured by Toagosei Kagaku, M-
400) 40 parts by weight, photocuring initiator (2-hydroxy-
2-methyl-1-phenylpropan-1-one, 2 parts by weight of Darocur 1173) manufactured by Ciba-Geigy, 5 parts of liquid crystal
0 parts by weight (of which, smectic liquid crystal (Merck, S
-6) 90%, nematic liquid crystal (M31, E31
LV) is 10%) Surfactant (Sumitomo 3M, Florard FC-430) 3 parts by weight A coating solution obtained by uniformly dissolving in 96 parts by weight of xylene is used with a blade coater having a gap of 50 μm. After coating,
Drying was carried out at 47 ° C. for 3 minutes, then vacuum drying was carried out at 47 ° C. for 2 minutes, and the coating film was immediately cured by infrared irradiation of 0.3 J / cm ² to obtain an information recording medium having an information recording layer having a film thickness of 6 μm. It was After extracting the liquid crystal from the information recording layer surface with hot methanol and drying it, the internal structure was observed with a scanning electron microscope (S-800 manufactured by Hitachi, Ltd.) at 1000 times. The liquid crystal phase is covered with a hardening resin and forms a continuous layer inside the layer.
It had a structure filled with a resin particle phase of 1 μm.

[Structure and Material of Integrated Type Intermediate Layer] The structure of the information recording medium in the reproducing / erasing apparatus of FIG. 6 is such that the optical sensor 107 and the information recording medium 108 are opposed to each other via the dielectric layer 200, and It is a laminated and integrated type.
This information recording medium is particularly suitable when the photoconductive layer in the photosensor is formed by coating using a solvent. When the information recording layer is directly formed by coating on the photoconductive layer, the information recording is caused by their interaction. It is possible to prevent image unevenness due to the liquid crystal in the layer being eluted, or the photoconductive material being eluted by the solvent for forming the information recording layer, and enabling the integration of the optical sensor and the information recording medium. It is a thing.

When forming the dielectric layer 200, it is necessary that the dielectric layer 200 has neither solubility in the photoconductive layer forming material nor the information recording layer forming material, and that it does not have conductivity. is there. In order to have conductivity, the space charge is diffused and the resolution is deteriorated, so that the insulating property is required. Moreover, the dielectric layer lowers the distribution voltage applied to the liquid crystal layer or deteriorates the resolution.
It is preferable that the film thickness is thin, and it is preferable that the film thickness is 2 μm or less.
On the contrary, the thinning causes not only the generation of image noise due to the interaction with time, but also the problem of penetration due to the lack of pinholes or the like in the multilayer coating. The penetrability due to the lack of pinholes varies depending on the solid content ratio of the material to be laminated and coated, the type of solvent, and the viscosity, so the thickness of the laminated coating is set appropriately, but at least 10 μm or less is preferable. , Preferably 0.1 μm to 3 μm. Further, in consideration of the voltage distribution applied to each layer, it is preferable to use a material having a high dielectric constant as well as a thin film.

As a material for forming the dielectric layer 200,
For inorganic materials, SiO ₂ , TiO ₂ , CeO ₂ , Al ₂ O
₃ , Si ₃ N ₄ AiN, TiN, MgF ₂ , FnS, a combination of silicon dioxide and titanium dioxide, a combination of zinc sulfide and magnesium fluoride, a combination of aluminum oxide and germanium, and the like, a vapor deposition method, a sputtering method, It may be formed by stacking by a chemical vapor deposition (CVD) method or the like. Further, a water-soluble resin having low compatibility with an organic solvent, for example, polyvinyl alcohol, water-based polyurethane,
An aqueous solution such as water glass may be used and laminated by spin coating, blade coating, or roll coating. Further, a coatable fluororesin may be used, and in this case, it may be dissolved in a fluorine-based solvent and applied by a spin coating method, or may be laminated by a blade coating method, a roll coating method or the like. As applicable fluororesin,
For example, the fluororesins disclosed in JP-A-4-24728 and organic materials such as polyparaxylylene and polyvinyl alcohol which are film-formed in a vacuum system can be preferably used.

As described above, as the information recording medium, the recording by the information exposure is visualized by the alignment of the liquid crystal. By selecting the combination of the liquid crystal and the resin,
It is possible to impart memory property without erasing the information that is once oriented and visualized. Further, by heating to a high temperature near the isotropic phase transition, the memory property can be erased, so that it can be used for information recording again.

[0045]

As described above, according to the information reproducing / erasing apparatus of the present invention having the heat erasing section, immediately after reproducing the information recorded on the information recording medium, the temperature of the information recording layer is changed by the heat erasing section. Since it is configured to erase the information recorded on the information recording medium by raising the temperature to an erasable temperature, there is no afterimage due to the strong memory of the information recording medium, and there is always a good condition under which there is no afterimage or noise. Therefore, the same information recording medium can be used for information recording. Further, according to the information reproducing / erasing apparatus of the present invention having the electric field erasing section, first, the temperature of the information recording layer is raised to a erasable temperature to make the information recording layer in the light scattering state, and then the light transmitting state is once caused by the electric field. Further, since the light scattering state is returned to, the erasing performance of the information recorded in the information recording device is high, there is no afterimage and noise, and uniform erasing can be performed over the front surface.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an information recording device.

FIG. 2 is a diagram showing a laminated recording medium.

FIG. 3 is a diagram illustrating information recording.

FIG. 4 is a diagram illustrating reading of recorded information.

FIG. 5 is a diagram illustrating an information reproducing device.

FIG. 6 is a diagram showing a configuration of an information reproducing / erasing apparatus having a reproducing unit and a heat erasing unit.

FIG. 7 is a diagram showing a configuration of an information reproducing / erasing apparatus having a reproducing unit and an electric field erasing unit.

FIG. 8 is a diagram showing a modification of erasing.

FIG. 9 is a diagram showing a configuration of an information reproducing / erasing device having dielectric heating erasing means.

FIG. 10 is a diagram showing a configuration of an information reproducing / erasing apparatus having an erasing means by laser light irradiation.

FIG. 11 is a diagram illustrating an erasing mechanism of a card-shaped medium.

FIG. 12 is a diagram illustrating an erasing mechanism of a disc-shaped medium.

[Explanation of symbols]

107 ... Optical sensor, 108 ... Information recording medium, 214 ... Heater power source, 212, 213 ... Roller, 216 ... Recording film, 217 ... Electric field generator, 219 ... Sheet heating element, 2
20 ... Line-shaped heating element, 221 ... Head-shaped heating element, 23
0 ... High frequency power source, 231, ... High frequency oscillator, 232 ... Electromagnetic shielding container, 240 ... Laser, 250 ... Card medium, 2
60 ... Disk-shaped medium.

Claims (7)

[Claims] 1. An information reproducing means for reproducing information recorded on an information recording medium comprising a support, a transparent electrode, a polymer dispersion type liquid crystal layer or a polymer-liquid crystal composite layer, which are sequentially laminated, and the information recording means. An information reproducing / erasing apparatus comprising: a heat erasing means for erasing information recorded on a medium by heating the information recording medium to a predetermined temperature. 2. An information recording medium comprising a support, a lower transparent electrode, a polymer-dispersed liquid crystal layer or a polymer-liquid crystal composite layer, a dielectric layer, a photoconductive layer, and an upper transparent electrode, which are sequentially laminated with liquid crystal. An information reproducing means for reproducing information recorded by orienting it, and a heat erasing means for erasing the information recorded on the information recording medium by heating the information recording medium to a predetermined temperature and erasing the information. Characteristic information reproducing / erasing device. 3. The device according to claim 1, wherein
The information reproducing / erasing apparatus is characterized in that the heating / erasing means is arranged behind the information reproducing means in a transfer path of the information recording medium. 4. The device according to claim 1, wherein
An information reproducing and erasing apparatus comprising: an electric field applying and erasing means for erasing an image by further applying an electric field to an information recording medium heated to a predetermined temperature by a heating and erasing means. 5. The apparatus according to claim 1, wherein the heat erasing means erases information by heating by a heating element, high frequency heating, or heating by laser light irradiation. Information reproducing / erasing device. 6. The information reproducing / erasing apparatus according to claim 5, wherein the heating element has a roller shape, a surface shape, a line shape, or a head shape. 7. The apparatus according to claim 1, wherein the information recording medium has a film shape,
An information reproducing / erasing apparatus characterized in that it has a card shape or a disk shape.