JP2000233523A - Erasing device for thermally reversible recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an erasing device for a thermally reversible recording medium wherein an erasing/heating means such as a heating roller can be cleaned, charging thereto can be prevented and sticking of dust and destruction of a thermal head due to static electricity can be prevented in a simple structure. SOLUTION: A coating means 500 for coating a silicone oil on an erasing/ heating means such as a heating roller 1 is provided. In the coating means, a holding section 502 holds a brush 501. A pair of elastic members 504 are fixed to both of end sections of the erasing/heating means, respectively. The pair of elastic members 504 are respectively engaged with recess sections 503a of both of end arm sections 503 of the holding section 502, thereby making the coating means 500 to be detachable to the heating roller 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer or the like using a thermoreversible recording medium (TC film or CTC film) capable of printing or erasing printed contents by a thermal reaction between a leuco dye and a developer. The present invention relates to an erasing device for erasing a print content of a thermoreversible recording medium in an image forming apparatus.

[0002]

2. Description of the Related Art Hitherto, the following method has been proposed as a method for erasing the print content of a thermoreversible recording medium using a TC film or a CTC film. A method of uniformly heating a certain area with a stamp-shaped head (suitable for TC cards and CTC cards). Method using a thermal head (JP-A-5-131)
746). Method using a rod-shaped erasing head (JP-A-56-8)
No. 6777). Method using a heat roller (JP-A-5-3027)
No. 7).

[0003]

However, when a stamp-shaped head is used, the area that can be erased is limited.
At present, it is practically used only at the size of a card at most. If an attempt is made to increase the area, there is a problem that the size of the entire apparatus also increases, and power consumption increases.

In the method using a thermal head, erasing can be performed by turning on all bits of the head. However, in this case, static electricity is easily generated due to friction between the thermal head and the film, and if the recording bit of the thermal head is destroyed by the static electricity, pixel omission occurs and the black streak is not completely erased. Will remain. In addition, since the thermal head and the film are always in frictional contact with each other, there is a problem that if dust or the like enters, the film may be streaked.

In the case of a rod-shaped heater, as in the case of the thermal head, if dust or the like enters between the erasing head and the film, the film will be striped.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to clean an erasing heating means such as a heating roller and at the same time to prevent electrification, thereby preventing adhesion of dust and the like and prevention of destruction of a thermal head due to static electricity. An object of the present invention is to provide an apparatus for erasing a thermoreversible recording medium which can be realized by the configuration.

[0007]

According to the present invention, there is provided an erasing apparatus for erasing a print content by heating a thermoreversible recording medium by an erasing heating means, wherein coating means for applying silicon oil to the erasing heating means is provided. It is characterized by.

Preferably, the application means is detachable for replacement. The application means may be, for example, one in which a brush is held by a holding section. In this case, it is preferable that the application unit be detachable by engaging both ends of the holding unit with a pair of elastic members fixedly arranged at both ends of the erasing heating unit.

[0009]

Next, an embodiment of the present invention will be described with reference to the drawings.

First, the mechanism of writing and erasing on a thermoreversible recording medium utilizing a thermal reaction between a leuco dye and a developer will be briefly described by taking a CTC film as an example.

FIG. 1 is an enlarged sectional view of a CTC film. The overall thickness is about 0.1 mm to 0.2 mm.
From the top, a protective layer 101, an intermediate layer 102, a recording layer 103, and a base material 104 are arranged in this order.

First, when the temperature is raised to about 170 ° C. or higher, the leuco dye in the recording layer 103 reacts with the developer to form a color. Next, when the temperature is set to 120 to 160 ° C., the bond between the leuco dye and the developer is released, and a translucent cloudy state is obtained. Therefore, when a white material is used for the base material 104 (PET or the like), the colored portion can be erased.
Further, when the temperature is raised to about 170 ° C. or more again, the recording layer 1
The leuco dye in No. 03 reacts with the developer to form a color.

By utilizing such a mechanism, for example, the film can be cut into a sheet shape, and can be recorded by heating with a thermal head while being conveyed at a certain speed, and then at a slightly lower temperature. If the printed content is erased by heating evenly, it can be used as a thermoreversible recording medium that can be used repeatedly.

FIG. 2 is a schematic configuration diagram of an erasing device according to the present invention. This erasing device includes a heating roller 1 as a heating means for erasing, a pressing roller 2 as a pressing means to the heating roller 1, a driving means 3 for the heating roller 1, a voltage applying means 4 to the heating roller 1, a temperature detecting means. 5, temperature control means 6 and the like.

The pressing roller 2 is a rubber roller having a low hardness and a high heat resistance, for example, silicon rubber. As shown in FIG. 3, both sides of the shaft 2 a of the pressure roller 2 are urged by an elastic body 2 c such as a spring via a bearing 2 b, and the pressure roller 2 is pressed against the heating roller 1. When the heating roller 1 rotates, the pressure contact roller 2 rotates, and the sheet-like thermoreversible recording medium 7 is fed between the nips at a constant transport speed. During this time, the thermoreversible recording medium 7 is heated by the heating roller 1, and the bond between the leuco dye and the developer is released to be translucent, so that the content recorded on the thermoreversible recording medium 7 is obtained. Is erased.

A driving force is applied to the heating roller 1 by a driving means 3. The driving means 3 is constituted by a motor or the like, and its rotation is transmitted to the heating roller 1 via gears 11 and 10 or general transmission parts such as a timing belt and a pulley as shown in the figure.

The temperature detecting means 5 uses a thermistor here. The temperature detecting means 5 is in pressure contact with the heating roller 1 and outputs a change in temperature as a resistance value. While measuring the value, the temperature controlling means 6 controls the voltage applying means 4 so that the temperature becomes constant. Controlling output.

The heating roller 1 shown in FIG. 3 is a hollow metal roller, and its surface is coated with a heat-resistant and slidable coating such as Teflon coat. A heating element 8 is mounted inside the hollow metal roller with both ends held. The heating element 8 is a halogen lamp here,
Other heaters may be used as long as they provide the same effect. Both ends of the metal roller are held by bearings 9.

FIG. 4 is an explanatory view of the structure of a ceramic heat roller as another example of the erasing heating means. The ceramic heat roller includes an electrode 401 and a heating element 40 from the inside.
2, insulating layer 403, core material 404, coating layer 405
It is comprised in the order of. The electrode 401 is made of a metal such as brass and is connected to the voltage applying means 4 in FIG. The heating element 402 is a so-called ceramic heater and is made of lead-based glass and silver-based conductive material, and generates heat when a voltage is applied. For the insulating layer 403, a resin material such as polyimide is used.
And the core member 404 are electrically insulated. The core material 404 is
Made of metal such as aluminum alloy, ceramic heater 40
2 is transmitted to the core 404 via the insulating layer 403. The surface of the core 404 is coated with Teflon or the like.

Such a ceramic heat roller has a higher thermal efficiency than a heat roller using a halogen lamp as a heating element.
Power consumption can be reduced. This ceramic heat roller can also perform the same function as described above when used together with the pressure roller 2, the driving means 3, the voltage applying means 4, the temperature detecting means 5, the temperature controlling means 6 and the like as shown in FIG. it can.

The temperature distribution can be arbitrarily changed by changing the distribution density in the longitudinal direction of the heating element 402 constituting the ceramic heater. By increasing the density, a uniform temperature distribution can be obtained in the longitudinal direction, so that uniform erasing can be performed.

Finally, a heating port 1 as shown in FIG.
Alternatively, an application means for applying silicon oil to the ceramic heat roller as shown in FIG. 4 will be described with reference to FIG.

The application means 500 is made of a fiber material such as felt, and holds a brush 501 impregnated with an appropriate amount of silicone oil in a holding section 502. The brush 501 has a length corresponding to the heating roller 1. V-shaped concave portions 503a are provided on the outer surfaces of the arm portions 503 at both ends of the holding portion 502.

On the other hand, in a housing (not shown), a pair of elastic members (leaf springs) 504 having one end fixed thereto are disposed at both ends of the heating roller 1, and are attached to and detached from the concave portions 503 a at both ends of the coating means 500. It is designed to engage freely. In the engaged state, the brush 501
Are brought into sliding contact with the heating roller 1 with an appropriate pressure. When the heating roller 1 rotates, the silicone oil impregnated in the brush 501 is automatically applied to the surface of the heating roller 1.

As a result, it is possible to prevent static electricity from being charged between the thermoreversible recording medium and the heating roller 1 and at the same time to clean the thermoreversible recording medium and dust adhered to the heating roller 1. When the brush 501 becomes dirty, the brush 501 can be easily replaced by removing the holder 502.

[0026]

According to the first and second aspects of the present invention,
In a thermoreversible recording medium (TC film, CTC film) erasing device for printing or erasing printed content by a thermal reaction between a leuco dye and a developer, silicone oil is applied to erasing heating means. Since the means is provided, static electricity can be prevented from being charged between the thermoreversible recording medium and the erasing and heating means, and at the same time, dust and the like attached to the thermoreversible recording medium and the erasing and heating means can be cleaned.

According to the third and fourth aspects of the present invention, since the means for applying the silicone oil is provided so as to be easily attached and detached, even if the applying means becomes dirty, it can be easily replaced.

[Brief description of the drawings]

FIG. 1 is a schematic composition diagram of a thermoreversible recording medium.

FIG. 2 is a schematic view of an erasing device according to the present invention.

FIG. 3 is a schematic configuration diagram of the above.

FIG. 4 is a configuration explanatory view of a ceramic heat roller as another example of the erasing heating means.

FIG. 5 is a perspective view of a heating roller and an application unit for applying silicon oil.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 heating roller 2 press roller 2 a shaft 2 b bearing 2 c elastic body 3 driving means 4 voltage application means 5 temperature detection means 6 temperature control means 7 thermoreversible recording medium 8 heating element 9 bearing 10/11 gear 500 application means 501 brush 502 holding Part 503 arm part 503a concave part 504 elastic member

Claims (4)

[Claims] 1. An erasing apparatus for erasing printed contents by heating a thermoreversible recording medium by erasing and heating means, wherein said erasing and heating means is provided with an application means for applying silicone oil. For erasing non-volatile recording media. 2. The erasing device for a thermoreversible recording medium according to claim 1, wherein the application unit holds a brush on a holding unit. 3. The erasing apparatus for a thermoreversible recording medium according to claim 1, wherein said coating means is detachable. 4. The coating means is detachable by engaging both ends of the holding part with a pair of elastic members fixedly arranged at both ends of the erasing heating means. 2. The apparatus for erasing a thermoreversible recording medium according to item 2.