JPH08142357A - Image forming apparatus - Google Patents

Abstract

PURPOSE: To effectively prevent the adhesion of refuse to a thermal head by arranging a member cleaning a printing and erasing means to the area corresponding to the contact position of the printing and erasing means with a reversible thermal recording material but out of the region of the reversible thermal recording material. CONSTITUTION: When a reversible thermal recording material is printed or erased by the thermal head 2 of a serial printer, the thermal head 2 moves while presses the reversible thermal recording material 1 to a platen 3 and, after the completion of printing or erasure, the thermal head 2 returns to a rising start point. A cleaning sheet 5 is arranged to the area corresponding to the contact position of the thermal head 2 with the reversible thermal recording material 1 but out of the region of the reversible thermal recording material 1. Prior to printing or erasure, cleaning is performed in such a state that the thermal head 2 is pressed to the cleaning sheet 5. By this constitution, the adhesion of refuse to the thermal head 2 can be effectively prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using a reversible thermosensitive recording material capable of repeating writing and erasing of information by heating.

[0002]

2. Description of the Related Art Conventionally, when recording is performed using a thermal head, foreign matter on the surface of the recording material or dust scraped off by the thermal head adheres to the heating element of the thermal head during continuous recording due to heat and pressure of the thermal head. This causes a defect that the recorded image is cut off in proportion to the number of recordings. In particular, a reversible thermosensitive recording material in which the same surface is repeatedly contacted with a thermal head (recording material whose transparency reversibly changes depending on temperature change): JP-A-55-
No. 154198), the surface is easily scraped, and the problem of dust deposits on the thermal head is strongly desired to be improved. To solve these drawbacks, a method of weakening the heat and pressure of the thermal head, a method of adding heat resistance and lubricity to the surface of the thermal head, etc. have been adopted, but they are still insufficient.

However, JP-A-4-173289, JP-A-5-28624, and the like propose proposals for preventing dust adhesion to the thermal head. However, in these proposals, it is said that the recording material itself is processed so as to have a cleaning function, so that the number of manufacturing steps of the recording material itself is increased, and in addition, the product image of the recording material is impaired. There is an inconvenience.

Further, various thermal head cleaning methods are known in general thermal paper printers and thermal transfer printers. For example, as shown in Japanese Patent Application Laid-Open No. 4-5839, there is a cleaning dedicated member. In this example, the user has to perform cleaning every time recording or erasing is complicated. In Japanese Patent Publication No. 2-238977, a cleaning device is provided between the thermal head and the thermal transfer ribbon.
The cleaning device here has a complicated function, the pressure applied to the thermal head is weak, and the replacement of the cleaning member is troublesome.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned inconveniences and drawbacks, to effectively prevent dust from adhering to the thermal head, and to record and erase on reversible thermosensitive recording materials. An image forming apparatus that can perform high quality is provided.

[0006]

SUMMARY OF THE INVENTION The present invention is an image forming apparatus using a reversible thermosensitive recording material capable of repeating writing and erasing of information by heating, wherein the member for cleaning the printing / erasing means is the printing. The feature is that it corresponds to the position where the erasing means is placed on the reversible thermosensitive recording material and is arranged outside the region of the reversible thermosensitive recording material. As used herein, "the cleaning member corresponds to the position where the printing / erasing means is attached to the reversible thermosensitive recording material and is located outside the area of the reversible thermosensitive recording material" means that the cleaning member is the printing / erasing means. It means that the cleaning member is positioned so as not to come into contact with the reversible thermosensitive recording material, although it reaches the position of the reversible thermosensitive recording material.

The image forming apparatus of the present invention, which will be described in more detail below, has a printing / erasing means (generally a thermal head is used) used for printing and erasing on a substantially reversible thermosensitive recording material. An apparatus having a member for cleaning is provided. Further, the "reversible thermosensitive recording material" in the present invention means a state of a first color at a first specific temperature higher than room temperature, and after heating at a second specific temperature higher than the first specific temperature, It means a reversible thermosensitive recording material which is brought into a second color state when cooled, and specifically, the following recording materials (1), (2), (3) and (4) are mentioned. . (1) TC: a transparent state at a first specific temperature and a cloudy state at a second specific temperature (Japanese Patent Laid-Open No. 55-1541).
No. 98) (2) CTC-color is developed at a second specific temperature and is erased at a first specific temperature (Japanese Patent Application No. 2-414438) (3) A white turbid state occurs at the first specific temperature. , Those which become transparent at the second specific temperature (Japanese Patent Laid-Open No. 3-169590) (4) Those which develop black, red, blue, etc. at the first specific temperature and disappear at the second specific temperature ( JP-A-2-188293,
(JP-A-2-188294)

As a means for printing and erasing on the reversible thermosensitive recording material of the present invention, either a frame sequential system or a line sequential system can be adopted. For example, the one shown in FIGS.
When printing or erasing the reversible thermosensitive recording material 1 with the serial type thermal head 2, the reversible thermosensitive recording material 1 is pressed against the platen plate 3 to move the thermal head 2, and after the printing or erasing is completed, the thermal head 2 Is a device that goes up and returns to the starting point. In order to increase the temperature efficiency, a heater may be provided on the back surface of the thermal head 2 for preheating to perform efficient printing / erasing, and a heater may be provided on the platen plate 3 for preheating. May be. The thermal head 2 is the most typical example of the printing / erasing means, and also includes a hot stamp, a heat roll,
Infrared heat generation, laser heat generation, ultrasonic waves, etc. can also be a printing / erasing means. Therefore, for convenience of explanation of the present invention, the thermal head 2 is used as the printing / erasing means. Although the apparatus shown in FIG. 1A is not provided with a cleaning member, the cleaning sheet 5 is attached to the apparatus shown in FIG.

2, FIG. 3, and FIG. 4 each show a state in which the thermal head 2 is cleaned with a cleaning sheet (cleaning member) 5 prior to printing / erasing. FIG. 2 shows the thermal head 2 and the platen plate 3
This is a device that performs cleaning while being pressed against the upper cleaning sheet 5. Reference numeral 7 in FIG. 2 represents an adhesive layer. FIG. 3 shows an apparatus for cleaning the reversible thermosensitive recording material 1 in a state where the back surface of the end portion of the cleaning sheet 2 is pressed against the top surface of the tip portion. FIG. 4 shows an apparatus in which the cleaning sheet 2 is pressed more reliably onto the reversible thermosensitive recording material 1 shown in FIG. 3 by using a leaf spring 8 or the like.

In the apparatus shown in FIGS. 2, 3 and 4, the cleaned thermal head 2 is subsequently transferred onto the reversible thermosensitive recording material 1 for recording or erasing, as indicated by the arrow on the paper surface. . When this recording or erasing is completed, as shown in FIG. 5A or 5B, the thermal head 2 is lifted up and returns to the starting point.

FIGS. 6 and 7 show an apparatus in which the pressing of the thermal head 2 after the completion of printing / erasing is performed outside the reversible thermosensitive recording material 1 and the cleaning sheet 5 is provided at that position. According to this, the cleaning sheet 5 also removes the dust of the reversible thermosensitive recording material 1 attached to the thermal head 2 by printing / erasing.

FIG. 8 shows the reversible thermosensitive recording material 1 with the cleaning sheet 5 in front of the direction in which the thermal head 2 advances.
This is a device that prints and erases while pressing. Considering that most of the dust attached to the reversible thermosensitive recording material 1 has static electricity, it is advantageous to provide the static elimination brush 9 ahead of the thermal head 2 as shown in FIG. Is.

The cleaning sheet 5 in the present invention is a sheet of paper, plastic film, non-woven fabric, synthetic paper,
Alternatively, it is effective to use a composite sheet of these, particularly a fibrous sheet. Further, these may be provided with irregularities on the surface thereof, may be attached with an abrasive, etc., and may be those in which alcohol, water, etc. have been permeated.

[0014]

EXAMPLES Next, the present invention will be described more specifically with reference to examples.

Example 1 Reversible thermosensitive recording material (total thickness 70-80 μm, size A)
4. Erase temperature 80 to 100 ° C.) As shown in FIG. 1A, a ceramic heater (temperature 80 to 90 ° C.) is provided on the back surface of the thermal head of the Ricoh NT310 printer.
A ceramic heater (temperature 70 to 8
(0 ° C.) to prepare a device for printing / erasing, and attaching the cleaning sheet (PPC type, 6000 Ricoh Co., Ltd.) shown in FIG. , There is no erasing defect, and there are no marks left at the start.

Example 2 Reversible thermosensitive recording material (total thickness 70 to 80 μm, size A)
4. Erase temperature 80 to 90 ° C.) As shown in FIG. 1A, a ceramic heater (temperature 80 to 90 ° C.) is provided on the back surface of the thermal head of the Ricoh NT310 printer.
A ceramic heater (temperature 70 to 8
A device for printing / erasing is prepared by providing a cleaning sheet shown in FIG. 2 (manufactured by DNP, about 20 ° C.).
(0 μm thickness) was glued with a double-sided tape and printed / erased. As a result, scratches, scratches on the print, erasing defects, and dent marks at the start were eliminated.

Example 3 A double-sided tape was used to attach a cleaning sheet (made by Nippon Micro Coating Co., Ltd., about 200 μm thick) as shown in FIG. 3 to the printer shown in FIG.
Under the cleaning sheet, a reversible thermosensitive recording material (total thickness 120 to 130 μm, size A
After printing / erasing with 4) in between, scratches, print scratches, and erasing defects disappeared, and there were no traces of punching at the start, and even thick objects could be easily cleaned.

Example 4 The printer of FIG. 1 (a) described in Example 3 is provided with a leaf spring as shown in FIG. 4, and a cleaning sheet (made by DNP) having a thickness of about 200 μm is almost the same as in Example 1. Similar reversible thermosensitive recording material (total thickness 120 to 130 μm, size A
When 4) was applied and printing / erasing was performed, in addition to the above effect, the probability that the cleaning sheet did not need to be under the thermal head for the next cleaning before printing / erasing was 0. This is because most of the cleaning is applied, curling occurs, hits the thermal head, and is placed on the thermal head.

Example 5 In the printer described in Comparative Example 2 below, a cleaning sheet as shown in FIG. 6 (manufactured by DNP, 200 μm thick) is used.
The thermal head is applied to the outside of the reversible heat-sensitive recording material (total thickness 200 to 300 μm, size A4) by sticking with a double-sided tape, and cleaning is performed to eliminate wear of the thermal head, It has become possible to repeat 100,000 times or more.

Example 6 A cleaning sheet (PPC type 6000, manufactured by Ricoh Co., Ltd.) as shown in FIG. 7 was attached to the printer described in Comparative Example 2 below with a double-sided tape on the entire surface of the platen plate to give a reversible feeling. When printing / erasing the thermal recording material (size free), the life of the thermal head was long and printing of various sizes was possible.

Embodiment 7 The printer described in Embodiment 3 has the same structure as shown in FIG.
Before the thermal head was moved, a cleaning sheet (Toraysee, Toray) was set and the reversible thermosensitive recording material was printed / erased. The defect is even better.

Embodiment 8 The printer described in Embodiment 7 has the same structure as shown in FIG.
Conductive brush (Synthetic fiber polyester, Elekbar H
Type, manufactured by Shishido Co., Ltd.) was set before moving the thermal head, and printing / erasing of the reversible thermosensitive recording material was performed. Has improved.

Comparative Example 1 When the reversible thermosensitive recording material of Example 1 was printed / erased with the printer described in FIG. 1 (a), scratches, dents, print scrapes, and erasing defects were observed. It was only twice durable.

Comparative Example 2 In the printer and cleaning sheet of FIGS. 1 (a) and 3 described in Example 3, the thermal head as shown in FIG. 5 (b) was extended to the outside of the reversible thermosensitive recording material. When the material was continuously applied, lifted up, and returned to the starting point, the above-mentioned material had no traces of impact, but more dust adhered and more wear of the thermal head.

[0025]

According to the first, second and third aspects of the present invention, the reversible thermosensitive recording material has improved repetitive durability, print smearing and erasing defects are eliminated, and cleaning of the thermal head can be omitted. . Particularly, according to the inventions of claims 2 and 3, the size of the apparatus can be reduced. According to the invention of claim 4, since the cleaning sheet is sandwiched between the reversible thermosensitive recording material and the thermal head, the cleaning sheet is prevented from coming off the thermal head as much as possible. According to the fifth and sixth aspects of the present invention, dust and dirt attached to the thermal head are eliminated, and print blur and erasing failure are further eliminated. According to the inventions of claims 7 and 8, the life of the cleaning sheet and the thermal head is improved.

[Brief description of drawings]

FIG. 1A is a diagram showing a state in which recording and erasing are performed on a reversible thermosensitive recording material by a serial method, and FIG. 1B shows a state in which a cleaning sheet is provided before and after the reversible thermosensitive recording material. Fig.

FIG. 2 is a diagram showing an outline of a main part of the present invention.

FIG. 3 is a diagram showing an outline of a main part of the present invention.

FIG. 4 is a diagram showing an outline of a main part of the present invention.

FIG. 5A is an explanatory view of a state in which the thermal head returns to the starting point after recording / erasing on the reversible thermosensitive recording material, and FIG. 5B shows pushing the thermal head to the outside of the reversible thermosensitive recording material. An explanatory view of a state in which the application is continued, then raised, and returned to the starting point.

FIG. 6 is a diagram showing a state in which the thermal head contacts the cleaning sheet after recording / erasing on the reversible thermosensitive recording material is completed.

FIG. 7 is a diagram showing a state in which the thermal head contacts the cleaning sheet after the recording / erasing on the reversible thermosensitive recording material is completed.

FIG. 8 is a diagram in which a cleaning sheet in contact with the reversible thermosensitive recording material is attached in front of the thermal head.

FIG. 9 is a diagram in which a static electricity removing brush that is in contact with the reversible thermosensitive recording material is mounted in front of the thermal head.

[Explanation of symbols]

 1 Reversible thermosensitive recording material 2 Thermal head 3 Platen plate 4 Conveying roll 5 Cleaning sheet 6 Static electricity removing brush 7 Adhesive layer 8 Leaf spring 9 Screw

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location B41M 5/18 101 A 7416-2H 5/26 102 (72) Inventor Kazumi Suzuki Ota-ku, Tokyo Magome 1 chome 3-6 In Ricoh Co., Ltd.

Claims (8)

[Claims] 1. In an image forming apparatus using a reversible thermosensitive recording material capable of repeating writing and erasing of information by heating, the member for cleaning the printing / erasing means is the reversible thermosensitive material of the printing / erasing means. An image forming apparatus, characterized in that the image forming apparatus corresponds to a position where the recording material is applied and is arranged outside the area of the reversible thermosensitive recording material. 2. The image forming apparatus according to claim 1, wherein a cleaning sheet is brought into contact with the printing / erasing means prior to printing / erasing on the reversible thermosensitive recording material. 3. The image forming apparatus according to claim 2, wherein the lower surface of the rear end of the cleaning sheet is positioned on the upper surface of the front end of the reversible thermosensitive recording material. 4. The image forming apparatus according to claim 2, wherein the rear end surface of the cleaning sheet is in contact with the front end surface of the reversible thermosensitive recording material. 5. The image forming apparatus according to claim 1, wherein the cleaning sheet is brought into contact with the printing / erasing means after the printing / erasing on the reversible thermosensitive recording material is completed. 6. The image forming apparatus according to claim 5, wherein the front end of the cleaning sheet is located in contact with or close to the rear end of the reversible thermosensitive recording material. 7. The image forming apparatus according to claim 2, further comprising means for removing stains on the reversible thermosensitive recording material before bringing the reversible thermosensitive recording material into contact with the cleaning sheet. 8. The image forming apparatus according to claim 2, further comprising means for removing static electricity on the reversible thermosensitive recording material before bringing the reversible thermosensitive recording material into contact with the cleaning sheet.