JPS62108092A - Recording and erasing of information and recorder - Google Patents

Abstract

PURPOSE:To enable images to be recorded at high speed, by disposing a preheating means, a thermal recording means and a cooling means in order on a recording material. CONSTITUTION:An image-forming belt 4 is intermittently driven in the state of being stretched in a looped form by a driving roller 2 and a driven roller 3. An image is recorded directly on the belt 4 by a heat pen 7. In addition, an image is formed as a dot pattern by operating a thermal recording means such as a thermal head 9 according to an external signal. Preheaters 5, 5a and 5b are disposed in contact with the sheet 4, opposite to the heat pen 7, the thermal head 9 and an erasing part 10, respectively. Assuming that the temperature at which phase separation takes place is X1 and the temperatures of the preheaters 5, 5a, 5b are X4, X4, X3, recording time and erasing time can be markedly shortened when the temperatures are so set that X1>X4>X3 normal temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for recording image information on an information recording medium that can be virtually recorded and erased by combining heating means and cooling time control means.

(Prior Art) Photochromic materials, thermochromic materials, magnetic recording materials, and the like are conventionally known as reversibly erasable and repeatedly usable information recording materials. Recently, as a thermal recording material to replace thermochromic materials,
Chalcogenide glasses that utilize phase change between crystalline and amorphous states, or systems that utilize thermal substance changes of low-molecular fatty acids, their amides, esters, or ammonium salts dissolved in thermoplastic polymers (especially JP-A-57-117140) and the like have been proposed. However, chalcogenide glass is expensive because the recording layer is produced by vapor deposition, and there are also problems with toxicity. Furthermore, films in which a low-molecular substance is dissolved in a thermoplastic polymer perform recording and erasing using a delicate temperature difference, and are currently not in practical use.

(Problem to be solved by the present invention) However, the new polymer recording material has a temperature difference of several hundred degrees.
It is said that there is a limit to the improvement of recording speed. The object of the present invention is to enable high-speed image recording using this new recording material.

(Means for Solving the Problems) The recording apparatus of the present invention is one in which a preheating means, a heating recording means, and a cooling means are sequentially disposed on a recording body using the above-mentioned recording material. By applying this preheating device, recording or erasing can be performed while the recording medium is heated close to a roughly separated state, so recording or erasing can be performed at a higher speed than when heating is performed for the first time during recording or erasing. It became.

On the other hand, when the temperature at which the phase separation state occurs is XI, and the temperature of the preheating means is t2, by constantly preheating the recording medium to a temperature t2 such that Xi>X2,
Recording and erasing times could be shortened, and a uniform opaque state could be obtained.

Assuming that the temperature at which the phase separation state occurs is xl, the preheating temperature during recording is Xa, and the preheating temperature during erasing is x4, in order to increase the contrast ratio more efficiently, rapid cooling during recording and x during erasing are performed. For slow cooling, XI -Xa>
The recording medium is preheated so that X1-Xa. In other words, by preheating the recording medium so that X 1 > X a > .

The polymeric recording material applied to the recording device of the present invention is composed of a thin layer made of a stable blend of two or more types of polymers, and is in a homogeneous and compatible state at a low temperature below a certain temperature, and at a temperature higher than this low temperature. On the other hand, 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 LC5T type (Lower Cr
1ticalSolution Tempretur
e) Combinations of several types of polymers are known as systems exhibiting a phase diagram. For example, polyvinylidene fluoride, polymethyl acrylate, polyethyl acrylate,
Combinations with polymethyl methacrylate, polyethyl methacrylate, etc., and combinations of polycaprolactone and polycarbonate (R, E, B6rnsteine)
t, a 1. Macromo 1e
OF681~(1977))
Polystyrene and polyvinyl methyl ether (M, Ban
ket,al,J,polym,Sci,N:2.1
0 P1097~(1972)), styrene-acrylonitrile copolymer and polycaprolactone (L, P
, Mc Master.

Macromolecules 6 F760-“ (1973)), styrene-acrylonitrile copolymer and polymethyl methacrylate (L, P, Mc
MaSter PolymPrepr, top'3
F254~ (1974), Polyvinyl nitrate and polymethyl acrylate (Sanbe Akiyama et al., Kobunshi Papers 33
P238-(1976)), polyvinylidene fluoride and polyvinyl methyl keto y (D, R, Paul et
.

al,,Polym,Eng,Sci,,18P122
5-(1978)), or ethylene-vinyl acetate copolymer and chlorine rubber (J.

Leffing well, et, al.

Pulym, Prepr, , 14F596
~(1973)) and so on. Depending on the blend ratio, these polymer combinations cause phase separation when heated to 100-200°C, and although there are differences in degree, light scattering is observed and the area becomes opaque compared to areas that are not heated. become

Furthermore, the polymer recording material can be fixed in a phase-separated state by rapidly cooling it from a heated phase-separated state, and the fixed phase-separated state can be restored to its original state by heating above the phase separation temperature and slowly cooling it. Return to the compatible state yE.

(Example) Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIGS. 1 and 2 are schematic diagrams of an embodiment of an apparatus for recording, erasing, and recording information and displaying the information.

In the figure, reference numeral 1 denotes an exterior of the apparatus, and an image forming belt 4, which is the recording medium, is stretched like an endless belt by a driving roller 2 and a driven roller 3 and is driven intermittently. The direction of rotation of each roller 2.3 is indicated by an arrow in the figure. Any method may be used to record and display images on the image forming belt 4 as long as it has a heating means, but for example, a heating pen 7 having a pen-shaped tip with a heater may be used to contact the image forming belt. By doing so, an image is directly recorded on the image forming belt 4 by an aging method.

This pen is used in a state in which the heater is automatically turned off when the pen is removed from the image forming sheet 4. Furthermore, an image can be directly written and displayed on the display surface using a recording device such as a pen-shaped device that generates heat from a light source.

On the other hand, external signals from computers, word processors, etc. are recorded by a thermal head 9 or a heating recording device such as a laser.
The image can also be formed as a dot pattern. These heating heads and the like may be of a fixed type or of a scanning type.

If you use a combination of the above recording methods, you can record and display external signals using a thermal head, etc., and add a thermal pen, etc.
It becomes possible to add to the image and display and record on the same surface.

A partially enlarged sectional view of the image forming belt carrying the polymeric recording layer is shown in FIG. That is, a recording layer 22 made of a combination of two or more types of polymers that can be phase-separated by heating as described above is coated on a heat-resistant base film 21 such as transparent polyester, and a surface protective layer 23 is applied if necessary. It may be provided.

When the recording layer is heated to a temperature sufficient to exceed the temperature required to cause phase separation, the combined polymers phase separate, resulting in an opaque state in which light is scattered due to the difference in refractive index. A similar change is observed when heating is applied using a pulsed thermal signal. Here, the state change of pulse heating is shown in FIG. 4. In the figure, the vertical axis represents the light scattering degree of the recording layer, the reciprocal of the transmittance, and the horizontal axis represents time. First, if a sufficient heat pulse exceeding the separation temperature is applied at time t, the change in light scattering degree as time passes becomes as shown in song IA. After being heated from room temperature at time to, the recording layer continues to become opaque until time t1 while it cools down and exceeds the separation temperature.

Then, when the mixture is cooled to below the phase separation temperature, the compatibility process begins again and the original transparent state returns (time 12). The rate of progress of such a change varies depending on the viscosity of the polymer used under heating, the size of the segments, and the degree of polymerization, but the process generally follows the process shown in FIG. 4.

What is interesting here is that if rapid cooling is performed once phase separation has progressed to a certain state, the viscosity of the polymer will increase and the phase separation state will be fixed. For example, time t in Figure 4
When rapidly cooled at 1, the opaque state is maintained as shown by curve B until it is heated again.

When recording a thermal signal as an optical signal in the above process,
In order to increase the information contrast, a combination of polymers with a large difference in refractive index is required. Generally, polyvinylidene fluoride has a low refractive index, and copolymers of polyvinylidene fluoride are effective in consideration of coating properties and solubility. In addition, one or more of the above-mentioned polymethyl acrylate, polyethyl acrylate, polymethyl methacrylate, polyethyl methacrylate, or polystyrene is used as a combination polymer with a high refractive index, and it is dissolved in a coating solvent and coated on the base film to a thickness of 0. .1 to 100 gm to obtain a polymeric recording film. Providing a protective layer of heat-resistant polymer such as polycarbonate or polyester on the outermost surface is effective in protecting the recording layer.

Furthermore, when the recording heating source is an optical beam, it is also effective to add a coloring material such as a dye that absorbs the beam light.

In the present invention, in order to efficiently change the opacity of the image forming sheet 4 by these heating recording and erasing means, preliminary heaters 5 and 5a are provided opposite to the heating recording and erasing means.
and 5b are placed in contact with the image forming sheet 4.

These preheating heaters 5, 5a and 5b are, for example,
A surface heater using a thin film resistor such as nickel alloy, carbon, aluminum, or ITO is used. These preheatings are a very important component in the present invention, and if the sheet 4 is transparent, if the preheating heater is a colored member including black, in addition to the above-mentioned characteristics, the contrast of the image in the display section will change. It is possible to display clear and easy-to-see images.

Furthermore, FIG. 5 shows state changes in the recording and erasing processes compared with the presence and absence of preheaters 5.5a and 5b in the same manner as in FIG. 4 described above.

In the figure, curves A and B are obtained in the same manner as shown in FIG. 4 above, when times t, ) and t2 are at room temperature and no preheating heater is provided.

One of the curves C and D corresponds to the preheating heaters 5 and 5a described above when the temperature at which the phase separation state occurs is x1.

5b and the temperatures of X4, X4, X3,! =ki,
It shows the state change when the condition is set such that X 1 > X 4 > X 3 > room temperature.

The results are shown in curves C and D for preheating heaters 5 and 5a.
, 5b by using 1 curve A.

As is clear from comparison with B, the recording and erasing times can be significantly shortened. Furthermore.

By controlling the temperature of rapid cooling (recording) and slow cooling (erasing), it is possible to form a transparent state and an opaque state with a uniform high contrast ratio.

In addition, as a modification of the above embodiment, the layer structure of the recording medium may be changed, for example, the recording medium itself may have a color layer including black. Further, although the preheating heaters are provided at various locations in FIG. 1, they may be provided only at one or two specific locations.

(Effects of the Invention) As described above, the present invention provides a recording, erasing, and display device equipped with a temperature-variable preheating means, which is much more efficient than a conventional information recording device that goes through a relatively complicated process. A more compact device configuration is possible, and recording, erasing, and display times can be shortened, and recording can be performed at higher speeds. Further, by providing a preheating means, it was possible to obtain a uniform image with a high contrast ratio.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a recording and display device explaining the present invention, and FIG.
Figure 1 is a plan sectional view of the device, Figure 3 is a partially enlarged view of the recording medium, Figure 4 is a graph showing changes in the state of the recording layer due to changes in the pulsed heat signal of the thermal head as a heating means, and Figure 5. shows a graph when a preliminary heater is used in the state shown in FIG. In the figure, 4 is an image forming sheet which is a recording medium, 5.5a
- 5b is a preliminary heater, 7 is a thermal pen, 9 is a heating head, and 10 is an erasing section. Appearing person: Canon Co., Ltd. 1,・,′ &−=,−,,−Ichiharuma−〉 4−1go11ha

Claims (3)

[Claims] (1) By heating an information recording medium in which at least a polymeric recording layer is laminated on a substrate, the state changes from a transparent state to an opaque state, and after heating, recording an image pattern that can fix the opaque state by controlling the cooling time; 1. An information recording, erasing and displaying apparatus, characterized in that a preheating means, a heating recording means, and a cooling means are sequentially disposed on the information recording medium. (2) The preheating means always preheats the information recording body to a temperature t_2 such that X_1>X_2, where the temperature at which the information recording body changes state is X_1 and the preheating temperature is X_2. An apparatus for recording, erasing, and recording information according to claim (1). (3) The preheating means sets the temperature at which the information recording medium undergoes a state change to X_1, the preheating temperature during recording to X_3,
Information recording according to claim (2), characterized in that a preheating means is provided that can vary the temperature X_3 and X_4 such that when the preheating temperature at the time of erasing is X_4, X_1>X_4>X_3. , erasure and recording device.