JPH05330244A - Recording apparatus - Google Patents

Abstract

PURPOSE:To provide a recording apparatus capable of certainly recording or erasing a visible image even under high temp. environment and capable of always obtaining a clear recording image. CONSTITUTION:The recording or erasure of a visible image is performed with respect to a recording medium 1 opacified or transparentized by the control of heat energy to repeatedly record or erase a visible image using a thermal head 8. A Peltier element 10 is provided on the downstream side of the thermal head 8 as a cooling means and controlled in its driving by a Peltier element control circuit 11. The Peltier element control circuit 11 compares the ambient temp. inputted from a temp. sensor 12 with set temp. and, when the ambient temp. is high, the Peltier element 10 is driven to cool the recording medium 1 having a visible image recorded by the thermal head 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention provides, for example, whitening or transparency by controlling heat energy,
The present invention relates to a recording apparatus for recording or erasing a visible image on a recording medium capable of repeatedly recording or erasing a visible image using a thermal recording means such as a thermal head.

[0002]

2. Description of the Related Art A conventional hard copy forms an image on a recording medium such as paper from the outside with a visual material such as ink or toner, or, like a thermal recording paper,
A permanent image is recorded by providing a recording layer on a substrate such as paper and forming a visible image on the recording layer.

However, with the recent construction of various network networks and the widespread use of facsimiles and copiers, the rapid increase in the consumption of these recording media causes problems of natural destruction such as deforestation and social problems such as waste disposal. Is causing. In order to deal with these problems, it is strongly demanded to reduce the consumption amount of the recording medium such as reproduction of recording paper. In response to this problem, a recording medium that can be repeatedly recorded / erased has recently received attention.

Therefore, as a recording medium having such characteristics, there has been proposed a recording medium capable of reversibly changing both the transparent state and the cloudy state depending on the temperature applied to the recording material (for example, JP-A-55-154198). (See the official gazette).

In the transparent state, when the temperature is raised from T1 to T3, the recording medium changes from the transparent state to the cloudy state, and even when the temperature returns to T1, the cloudy state is maintained as it is. Then, when the temperature of the recording medium is raised from T1 to T2 and returned to T1 again, the cloudy state is changed to the transparent state, and the transparent state is maintained as it is. This change can be repeatedly reproduced.

[0006]

However, in a recording medium composed of a low molecular weight / polymer composite film recording material which repeatedly shows both cloudy and transparent states due to the temperature history as described above, cloudiness occurs in a high temperature environment, for example, 35 ° C. Even if an image is recorded, there is a problem that the image density is lowered and a semi-cloudy image is often obtained. Furthermore, even if this semi-white cloudy image is erased, there is a problem in that it cannot be completely erased and the white cloudy image disappears and remains. Therefore, an object of the present invention is to provide a recording apparatus capable of surely recording or erasing a visible image even in a high temperature environment and always obtaining a clear recorded image.

[0007]

The recording apparatus of the present invention is a conveying means for conveying a recording medium on which a visible image can be recorded or erased by making it cloudy or transparent by controlling thermal energy. A thermal recording means for recording a visible image by selectively applying thermal energy for recording or erasing to a recording medium conveyed by the conveying means; and after recording the visible image by the thermal recording means. Based on the cooling means for cooling the recording medium on which the visible image is recorded, the temperature detecting means for detecting the ambient temperature of the apparatus, the temperature detected by the temperature detecting means, and the preset temperature. Control means for controlling the operation of the cooling means.

Further, the recording apparatus of the present invention comprises a conveying means for conveying a recording medium capable of recording or erasing a visible image by making it cloudy or transparent by controlling thermal energy, and this conveying. Thermal recording means for recording a visible image by selectively applying heat energy for recording or erasing to a recording medium conveyed by the means,
After the visible image is recorded by the thermal recording means, a cooling means for cooling the recording medium on which the visible image is recorded, a temperature detecting means for detecting the ambient temperature of the apparatus, and a temperature detecting means for detecting the ambient temperature are detected. And a control means for operating the cooling means when the temperature is equal to or higher than a predetermined value.

[0009]

Operation: For example, when the recording medium is repeatedly used,
If the ambient temperature of the device is higher than a predetermined value, after recording a visible image on the recording medium, the recording medium is cooled and the recording medium is cooled to a predetermined temperature or lower, so that the recording operation in a high temperature environment is prevented. Deterioration is resolved, and it does not deteriorate even if it is returned to the original environmental temperature. Therefore, it is possible to reliably record or erase a visible image even in a high temperature environment.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the structure of a recording apparatus according to the first embodiment. In the figure, reference numeral 1 is a recording medium, and a pair of conveying rollers 2 are sequentially arranged at predetermined intervals,
Further, the platen rollers 3, 4, and 5 convey the sheet in the direction of the arrow at a constant speed. A heat roller 6 is provided on the platen roller 3 as heat erasing means. The heat roller 6 is composed of a rotating metal sleeve whose surface is coated with urethane rubber or the like, and the heat generating lamp 7 is housed therein. The heat generating lamp 7 is driven to a constant temperature by a temperature control device (not shown).

A thermal head 8 as a thermal recording means is provided on the platen roller 4. The thermal head 8 applies thermal energy for recording to the recording medium 1 being conveyed, and is a line recording head having a plurality of heating resistors arranged in a line in a direction orthogonal to the conveying direction of the recording medium 1. is there. Each heating resistor of the thermal head 8 is
The thermal head drive circuit 9 selectively controls energization.

A Peltier element 10 as a cooling means is provided on the platen roller 5. Peltier element 10
Is a recording medium 1 on which a visible image is recorded by the thermal head 8.
Is cooled to a predetermined temperature and is driven by the Peltier element control circuit 11. Peltier element control circuit 11
Is configured to drive the Peltier element 10 on and off based on the temperature detected by the temperature sensor 12 as a temperature detecting means for detecting the ambient temperature of the apparatus and a preset temperature.

The cooling means for cooling the recording medium 1 may be, for example, a cooling roller in which cooling water is circulated inside a hollow metal roller.

The recording medium 1 is made of a low-molecular / high-polymer composite film recording material that repeatedly shows both cloudy and transparent states depending on the temperature history, and is capable of repeatedly recording or erasing a visible image. 2 is configured as shown in FIG. That is, in the recording medium 1, a colored layer 22 colored in black or the like, a recording layer 23 reversibly showing two states of transparent and cloudy, and a protective layer 24 are sequentially laminated on one surface of a base material 21. Is configured.

The recording layer 23 has, for example, temperature-whitening / transparency characteristics as shown in FIG. That is, in the transparent state, when the temperature is increased from T1 to T3, the transparent state becomes a cloudy state, and even when the temperature returns to T1, the cloudy state is maintained as it is. Then, when the temperature of the recording layer 23 is raised from T1 to T2 and returned to T1 again, the cloudy state is changed to the transparent state, and the transparent state is maintained as it is. This change can be repeatedly reproduced.

Recording of a visible image on the recording medium 1 is carried out by selectively making the recording layer 23 cloudy with the recording layer 23 being transparent and the colored layer 22 being a base color. The erasure is performed by making the cloudy image transparent. The recording layer 23 used here is about 7
It becomes transparent at 0 ° C to about 100 ° C, and the cloudiness becomes saturated at about 110 ° C or higher. Although the upper limit of the heating temperature is determined by the heat resistance of the protective layer 24 or the recording layer 23, it is about 180 ° C. in the recording medium 1.

Next, the operation of recording a visible image by the thermal head 8 of the recording apparatus constructed as described above will be described. First, the temperature of the recording medium 1 on which a visible image has already been recorded is set in advance so that the temperature of the recording layer 23 of the recording medium 1 is heated to about 70 ° C. to about 100 ° C. which is a transparentizing temperature. By passing under the heat roller 6, all of the recorded visible images are erased by heating (made transparent).

The recording medium 1 from which the existing image has been erased is
A new visible image is recorded by passing under the thermal head 8. For this recording, the heating resistor of the thermal head 8 corresponding to the image point to be recorded may be driven so that the recording layer 23 of the recording medium 1 is heated to 110 ° C. which is the clouding temperature range. The above recording operation is a rewriting recording operation that is also performed in the conventional recording apparatus.

Now, when the present recording operation is performed in a high temperature environment, for example, 35 ° C., the present inventors obtain a semi-cloudy image because the density of the recorded image is lower than that in the normal temperature environment. I found that I couldn't. Further, it was found that even in image erasing, sufficient image erasing was not performed and an image residue was generated. Such a phenomenon did not disappear even if the recording energy and the erasing temperature were changed.

Then, when recording and erasing were carried out in an environmental test room with different ambient temperatures, the results shown in FIG. 4 were obtained. FIG. 4 schematically shows the relationship between the ambient environment temperature and the recording (whitening) density (O symbol) and the erasing (clearing) density (Δ symbol). Thermal head 8
The recording energy and the erasing temperature of the heat roller 6 were set to optimum conditions at each environmental temperature.

The recording experiment was conducted as follows. An image was recorded on a recording medium in a transparent state which was left to stand at each environmental temperature, and the image density at that time was measured.
The erasing density was measured by erasing the recording medium 1 on which a short pattern was recorded by the thermal head 8 in a normal temperature environment at each environmental temperature and then erasing by heating with a heat roller 6 to measure the image density.

As is clear from FIG. 4, both the image density and the clearing density were significantly deteriorated from around 35 ° C., and the two densities tended to approach each other. Such a tendency was the same not only in a specific recording medium, but also in a plurality of recording media showing the state change shown in FIG.

As a result of various investigations against such a phenomenon, after recording and heating, if the recording medium 1 is cooled to a temperature below the change point shown in FIG. It was found that the erase density did not deteriorate. FIG. 5 schematically shows changes in image density when the image is recorded and cooled (O symbol, solid line) and when not cooled (□ symbol, alternate long and short dash line). In the figure, tH is the ambient temperature and tC is the cooling temperature.

Cooling is carried out in a water tank provided in the environmental test chamber.
Immediately after recording the visible image, the recording medium 1 was loaded, immediately taken out from the water tank, and left at ambient temperature. In addition, in the aquarium,
Water whose temperature was controlled was circulated from a cooling water circulation device connected to this.

Image densities and clearing densities were measured while changing the cooling water temperatures to 30 ° C., 25 ° C. and 20 ° C. for the environmental temperatures of 35 ° C. and 38 ° C., respectively. As a result, it was found that if the temperature after the image recording is cooled to a temperature below the threshold value indicating the recording operation failure, the image density and the clearing density are not deteriorated even when the temperature is returned to the environmental temperature where the operation failure occurs.

Further, there was no remarkable difference between the image density and the clearing density at each cooling water temperature, and the changes represented by the changes shown in FIG. 5 were shown. The setting of the cooling temperature can be experimentally obtained for the recording medium to be used as described above.

As described above, the recording apparatus of this embodiment is based on the above findings, and is provided with the cooling means for cooling the recording material after recording the visible image on the recording medium. It is characterized by

That is, in the recording apparatus of this embodiment, the Peltier element 10 which can be electronically cooled is used as a cooling means without using a refrigerant. The cooling operation of the Peltier element 10 is controlled by the Peltier element control circuit 11. The ambient temperature detected by the temperature sensor 12 is input to the Peltier element control circuit 11, and the control start temperature is set in advance. The control start temperature was determined by the method described above, but in the recording medium 1 used here, the threshold value was 35 ° C., so it was set to 30 ° C.

The Peltier element control circuit 11 compares the ambient temperature input from the temperature sensor 12 with the set temperature, and drives the Peltier element 10 if the ambient temperature is high to cool the recording medium 1 passing therethrough. The driving power of the Peltier device 10 is
The density of the recording image of the recording medium 1 passing therethrough is set so as not to be significantly different from the normal temperature environment. In this recording device,
It was set so that a stable image density could be obtained even at 40 ° C., which is the maximum temperature of the use environment. The setting of the driving power may be changed according to the difference between the ambient temperature and the set temperature.

Rewriting recording was carried out in an environment test room with set temperatures of 35 ° C. and 38 ° C., and good rewriting recording was achieved without any decrease in recording density and no recorded image residue observed in the conventional recording apparatus. .. When a visible image was recorded even in an environment of 25 ° C., the Peltier device 10 did not operate and good rewriting was possible.

FIG. 6 schematically shows the structure of a recording apparatus according to the second embodiment. This recording device directly applies a thermal energy for recording or erasing to a thermal head to directly rewrite a visible image recorded on a recording medium. The same parts as those in FIG. The description is omitted.

The visible image rewriting recording operation in this embodiment will be described below with reference to FIG. The example in FIG.
For example, an example is shown in which the character "L" is rewritten and recorded on the character "I". The characteristics of this recording operation are
This is because not only the heating element corresponding to the mark dot forming the image point but also the heating element corresponding to the space dot not forming the image point is electrically heated.

First, as shown in FIG. 7A, the character "I" is recorded on the recording medium, and the character "I" is recorded on the character.
As shown in FIG. 7C, when the character “L” is rewritten and recorded, the process of FIG. 7B is performed. That is, the heating resistor array 31 of the thermal head 8 is in contact with the recording medium 1, and the array of the heating resistors of the heating resistor array 31 is arranged to be perpendicular to the recording direction. The heating resistors of the heating resistor array 31 are provided in a sufficient number to record the width of the recording medium 1.

In FIG. 7, 32 is a part of the already recorded image "I" and 33 is the currently recorded image ".
Part of L ", 34 is part of the erased image" I ",
Reference numeral 35 is the re-recorded image point portion. When recording on the recording medium 1, it suffices to raise the heating resistor corresponding to the pixel of interest (mark dot) to a temperature at which the recording medium 1 rises to the cloudy temperature range, regardless of the existing image. In this case, the heating resistor corresponding to the pixel of interest (space dot) may be raised to a temperature at which the recording medium 1 rises to the transparent temperature range regardless of the existing image.

The thermal head 8 fixed in this way
While the recording medium 1 is conveyed under the heating resistor array 31 in the direction of the arrow, the heating resistors in the heating resistor array 31 are selectively heated to record a new image 33 and simultaneously erase the old image 32. Rewriting record is realized.

Also in the recording apparatus of this embodiment, when the cooling after recording was not performed, defective recording operation was observed in the high temperature environment as in the above even in the above rewriting recording. Therefore,
By driving the Peltier element 10 based on the environmental temperature detected by the temperature sensor 12 by the Peltier element control circuit 11 in the same manner as described above, a good recording operation was performed even under the environmental temperature indicating the malfunction. ..

In the above-mentioned embodiment, the case where the thermal head is used as the thermal recording means has been described, but the present invention is not limited to this. For example, laser thermal recording means using laser light or the like. Can also be used.

[0039]

As described in detail above, according to the recording apparatus of the present invention, for example, when the recording medium is repeatedly used,
If the ambient temperature of the device is higher than a predetermined value, after recording a visible image on the recording medium, the recording medium is cooled and the recording medium is cooled to a predetermined temperature or lower, so that the recording operation in a high temperature environment is prevented. Deterioration is resolved, and it does not deteriorate even if it is returned to the original environmental temperature. Therefore, good repetitive recording can be performed in a wider environmental temperature range than that of the conventional recording apparatus, and a visible image can be surely recorded or erased even in a high temperature environment, and a clear recorded image can always be obtained. ..

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a recording apparatus according to a first embodiment of the invention.

FIG. 2 is a vertical sectional side view showing the configuration of a recording medium.

FIG. 3 is a diagram for explaining a state of a recording material that can change to both a cloudy state and a transparent state depending on a history temperature.

FIG. 4 is a diagram for explaining a recording operation failure in a high temperature environment.

FIG. 5 is a diagram for explaining characteristics of a recording operation.

FIG. 6 is a diagram showing a schematic configuration of a recording apparatus according to a second embodiment of the present invention.

FIG. 7 is a diagram for explaining a recording operation of rewriting recording.

[Explanation of symbols]

1 ... Recording medium, 2 ... Conveying roller pair, 3, 4, 5 ...
Platen roller, 6 ... Heat roller (heat erasing means),
8 ... Thermal head (thermal recording means), 9 ... Thermal head drive circuit, 10 ... Peltier element (cooling means),
11 ... Peltier element control circuit, 12 ... Temperature sensor (temperature detection means).

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location 6956-2H B41M 5/18 101 A

Claims (2)

[Claims] 1. A transporting means for transporting a recording medium capable of recording or erasing a visible image by making it cloudy or transparent by controlling thermal energy, and a recording medium transported by this transporting means. Thermal recording means for recording a visible image by selectively applying heat energy for recording or erasing to the recording medium, and a recording medium on which the visible image is recorded after recording the visible image by the thermal recording means. Cooling means, a temperature detecting means for detecting the ambient temperature of the device, and a control means for controlling the operation of the cooling means based on the temperature detected by the temperature detecting means and a preset temperature. A recording device comprising: 2. A transporting means for transporting a recording medium capable of recording or erasing a visible image by making it cloudy or transparent by controlling thermal energy, and a recording medium transported by this transporting means. Thermal recording means for recording a visible image by selectively applying heat energy for recording or erasing to the recording medium, and a recording medium on which the visible image is recorded after recording the visible image by the thermal recording means. Cooling means for cooling the device, temperature detecting means for detecting the ambient temperature of the device, and control means for operating the cooling means when the temperature detected by the temperature detecting means is equal to or higher than a predetermined value. Characteristic recording device.