JP2003094823A - Reversible heat-sensitive recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reversible heat-sensitive recording medium wherein the stability in a coloring density and a coloring image is high, and the deleting property is favorable. SOLUTION: For this reversible heat-sensitive recording medium on a supporting body, a reversible heat-sensitive recording layer contains a reversible heat-sensitive composition which can form a relatively colored state due to a difference in the heating temperature and/or the cooling speed after heating, by using an electron donative color-developing compound and an electron acceptive compound. In such a reversible heat-sensitive recording layer, a compound represented by a formula (1) is used as a coloring/decoloring controlling agent. (In the formula, R1 and R3 each independently represent 6-22C chain-form hydrocarbon radicals. R2 represents a 2-12C chain-form hydrocarbon radial, or an aromatic group.).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a reversible thermosensitive color-forming composition utilizing a color-forming reaction between an electron-donating color-forming compound and an electron-accepting compound and controlling a thermal energy to form a color image. The present invention relates to a reversible thermosensitive recording medium capable of forming and erasing data.

[0002]

2. Description of the Related Art Conventionally, electron-donating color-forming compounds (hereinafter referred to as
Thermosensitive recording media utilizing the color-forming reaction between a color former or leuco dye) and an electron-accepting compound (hereinafter also referred to as a developer) are widely known, and can be used in facsimiles, word processors, scientific measuring instruments, etc. It has been widely used as an output sheet and recently as a magnetic heat sensitive card such as a prepaid card or a point card. But,
All of these conventional recording media that have been put into practical use have irreversible color development, and it is not possible to erase an image once recorded and repeatedly use it.

On the other hand, according to the patent publication, a recording medium capable of reversibly developing and erasing color is also proposed. For example, a recording medium which uses a combination of gallic acid and phloroglucinol as a color developer (Japanese Patent Laid-Open No. 2000-242242). JP-A-60-193,691), and compounds using a compound such as phenolphthalein or thymolphthalein as a developer (JP-A-61-161).
No. 237684), a recording layer containing a homogeneous compatible solution of a color former, a developer and a carboxylic acid ester (Japanese Patent Laid-Open Nos. 62-138556 and 62-138568).
JP-A-62-140881, etc.), using an ascorbic acid derivative as a developer (JP-A-63-63).
No. 173684), those using a salt of bis (hydroxyphenyl) acetic acid or gallic acid and a higher aliphatic amine as the color developer (JP-A-2-188293, JP-A-2-188294, etc.) ) Etc. are disclosed.

Furthermore, the present inventors have previously proposed that Japanese Patent Laid-Open No. 5-12.
In JP 4360, an organic phosphoric acid compound, an aliphatic carboxylic acid compound or a phenol compound having a long-chain aliphatic hydrocarbon group is used as a color developer, and by combining this with a leuco dye which is a color developing agent, color development and decolorization are performed. Reversible thermosensitive coloring that allows colors to be easily heated and cooled and that the colored and decolored states can be maintained stably at room temperature and that coloration and decoloring can be repeated. A composition and a reversible thermosensitive recording medium using the same as a recording layer have been proposed. Further, thereafter, use of a specific structure for a phenol compound having a long-chain aliphatic hydrocarbon group (described in JP-A-6-210954) is proposed.

The reversible thermosensitive recording medium produced by using these materials is capable of color development by a thermal head, erasing by hot stamping, etc., and repeated color development / erasing. However, these recording media have a high color density and a stable color image has poor erasability, and the temperature range for sufficiently erasing is high. Have problems such as low image quality and poor stability of the image area.

In order to solve such a problem, the present inventors use a specific compound having a chain hydrocarbon group in combination as a color-decoloring / discoloring controlling agent, as described in JP-A No. 11-70731. I have proposed.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a reversible thermosensitive recording medium having high color density and stability of a color image, and good erasability.

[0008]

Means for Solving the Problems The present inventors have made various investigations on stabilization of a color image and reduction of the erasing temperature, and as a result, an unsaturated bond in a chain hydrocarbon group is found. It was found that the erasability at relatively low temperature is improved by having

Although the detailed reason is not clear, the decoloring process is carried out in an agglomerated structure composed of a leuco dye and a color developing agent which form a colored state and a color developing / decoloring controlling agent represented by the following formula (1) of the present invention. Therefore, the ester group part breaks down the aggregation structure to promote decolorization, and the hydrogen bond formed by the amide group forms a stable colored aggregation structure in the image area, so that the concentration is high. Conceivable.

[0010]

[Chemical 2] In the formula, R ₁ and R ₃ each independently have 6 to 2 carbon atoms.
2 is a chain hydrocarbon group, R ₂ is a chain hydrocarbon group having 2 to 12 carbon atoms, or an aromatic group. )

That is, the above-mentioned problem is (1) of the present invention, in which "an electron-donating color-forming compound and an electron-accepting compound are used on a support, and a relative difference is caused by a heating temperature and / or a cooling rate after heating. In a reversible thermosensitive recording medium provided with a reversible thermosensitive recording layer containing a reversible thermosensitive composition capable of forming a color-developed state, a compound represented by the following formula (1) ) A reversible thermosensitive recording medium characterized by using the compound (1).

[0012]

[Chemical 3] (In the formula, R ₁ and R ₃ each independently have 6 to 22 carbon atoms.
Is a chain hydrocarbon group, and R ₂ is a chain hydrocarbon group having 2 to 12 carbon atoms, or an aromatic group. ) ”, (2)“ Reversible thermosensitive recording medium according to item (1), which has a thermoreversible recording unit and an information storage unit ”, (3)
"The reversible thermosensitive recording medium according to the item (2), wherein the information storage section is a magnetic recording layer or an IC", (4) "characterized by being processed into a card shape (5) The reversible thermosensitive recording medium according to any one of (1) to (3) above, which is used in the form of a roll. The reversible thermosensitive recording medium according to any one of the items (3).

Further, the above problem is solved by (6) "a display device characterized by using the reversible thermosensitive recording medium according to any one of (1) to (5)" of the present invention. To be achieved.

The color developing / decoloring control agent used in the present invention will be described below. R ₁ and R ₃ in the above formula (1) used as a coloring and decoloring control agent each have 6 to 2 carbon atoms.
2 is a chain hydrocarbon group, R ₂ is a chain hydrocarbon group having 2 to 12 carbon atoms or an aromatic group, and a preferable structure is represented by the following formulas (2) to (4). Is mentioned.

[0015]

[Chemical 4]

[0016]

[Chemical 5]

[0017]

[Chemical 6] In the formula, o represents an integer of 2 to 12, and p and q each represent 1 or 2.

Specific examples of the color development / decoloration control agent used in the present invention are shown in Table 1. However, the present invention is not limited to these.

[0019]

[Table 1-1]

[0020]

[Table 1-2]

The leuco dye used in the present invention includes:
One or more compounds used in this type of reversible thermosensitive recording medium can be used, and examples thereof include known dye precursors such as phthalide compounds, azaphthalide compounds and fluorane compounds.

Further, as the color developer used in the recording layer, a representative example is, for example, JP-A-5-124360.
JP-A-6-210954, JP-A-10-
Examples thereof include the compounds described in Japanese Patent Publication No. 95175. The color developer used here has a structure capable of developing a leuco dye in the molecule, such as a phenolic hydroxyl group, a carboxylic acid group or a phosphoric acid group, and a structure for controlling the cohesive force between molecules, such as a long chain. It is a compound having one or more structures in which chain hydrocarbon groups are linked. The linking part may be via a divalent or higher valent linking group containing a hetero atom, and the long-chain hydrocarbon group may also contain the same linking group and / or aromatic group. Specific examples of such a reversible developer are described, for example, in JP-A 9-290563 and JP-A 11-188969.

FIG. 1 shows the relationship between the color density and the temperature of the reversible thermosensitive recording medium of the present invention. The reversible recording layer using these leuco dye and developer develops and decolors by the process shown in FIG. When the initial decolored state (A) is heated, the leuco dye and the developer are melt-mixed at the temperature T ₁ or higher to develop a color (B), and when this state is rapidly cooled, the colored state is fixed. When the color-developed state (C) is heated, the color is erased at a temperature T ₂ lower than the color-developing temperature, and when cooled, the color-erased state is similar to the initial state.

As described above, the recording layer can be erased by controlling the heating temperature and the cooling rate after heating. Printing with this recording layer provides high contrast and excellent image quality. It is also excellent in storage stability and durability against repeated printing and erasing, and is particularly suitable as the reversible thermosensitive recording medium of the present invention. Printing on a reversible thermosensitive recording medium using this recording layer can be performed by a thermal head as in the case of normal thermal recording, and erasing can be performed by a temperature-controlled heat roller, a heating element such as a ceramic heater, and a thermal head. Therefore, it can be used in a small and simple rewriting device.

The reversible thermosensitive recording medium of the present invention forms a recording layer together with a leuco dye, a color developer and a color development / decoloration control agent together with a resin. The resin used at this time may be any resin as long as it can bind these materials to the support, and conventionally known resins are widely used. Among them, a resin curable by heat, ultraviolet rays, electron rays or the like is preferably used in order to improve durability during repetition, and a thermosetting resin using an isocyanate compound or the like as a crosslinking agent is particularly preferably used. .

Further, in the present invention, improvement in color developing sensitivity,
An under layer, a protective layer, a back layer, etc. may be provided for improving durability, light resistance, etc. In these layers, an organic / inorganic filler, an ultraviolet absorber, a lubricant, a coloring agent together with a resin. A pigment or the like can be used.

The support for the reversible thermosensitive recording medium of the present invention is only required to be able to retain the recording layer, and paper, synthetic paper, PET film or the like is preferably used. In addition, it may be used by being attached to another material through these supports.

The reversible thermosensitive recording medium of the present invention is provided with both the thermoreversible recording section and the information storage section, so that the information stored in the information storage section is displayed on the thermoreversible recording section. You can check the information without a device
The convenience is improved. A bar code, a magnetic recording layer, an IC recording unit, or the like is preferably used as the storage unit used at that time.

Further, these materials can be processed into a shape according to their use, such as a card shape, a sheet shape, or a roll shape. For cards processed, it can be applied to prepaid cards, point cards, credit cards, etc. In addition, sheets processed can be printed when processed to general document size such as A4 size. By using the erasing device, it can be widely used not only for trial printing but also for temporary output such as circulation documents and conference materials. Further, the rolled product can be used as a display board / bulletin board or an electronic blackboard by being incorporated in a device having a printing / erasing unit. Since such a display device does not generate dust or dirt, it can be preferably used in a clean room or the like.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION When the reversible thermosensitive recording medium of the present invention is provided with a rewritable bar code, it is preferable to provide a layer for specularly reflecting light on the back surface of the thermosensitive layer. . By providing the layer that specularly reflects light, the degree of white turbidity of the white turbid portion can be improved, the contrast can be improved, and the barcode reading accuracy can be improved.

When the reversible recording medium of the present invention is provided with both a rewritable bar code and an image, characters, numbers, etc. which a human visually recognizes, the reflectance is different.
It may consist of more than one part. That is, it is preferable to provide a layer that reflects the above-mentioned light on the back surface of the rewritable bar code and a layer that absorbs light, that is, a colored layer, on the back surface of the portion that is visually observed by humans. This is because when viewed by humans, for example, there is a color difference in addition to the difference in the amount of light between the image part in the clouded state and the non-image part in the colored state, and depending on the viewing angle, there may be an excess from the non-image part. The reversible visible image is made easier to see because the glare caused by the reflected light disappears.On the other hand, when reading this with a device such as a reflection densitometer or a bar code reader, the light is normally incident at an angle. The sensor is placed in the direction perpendicular to the plane and is read, because the colored layer absorbs at least a part of visible light and the contrast is lowered. Therefore, the colored layer in the reversible thermosensitive recording medium of the present invention is a layer composed of two or more kinds of portions having different reflectances with respect to visible light, and at least one of the portions absorbs visible light, and at least the other portion. As part of the layer that reflects visible light, it is easy to visually recognize the image,
In addition, it is possible to obtain a high contrast even in the measurement by the device.

For example, in the reversible thermosensitive recording medium of the present invention, as shown in FIG. 2A, a reversible thermosensitive recording layer (13) and a protective layer (14) are provided on a support (11). A film made of a support (11), as shown in FIG.
A reversible thermosensitive recording layer (13) and a protective layer (14) may be provided on the top of which a magnetic recording layer (16) is provided on the back surface of the support (11) to form a sheet or film, and magnetic recording is also possible. A back layer (15) can be provided on the layer (16), and the back layer (15) can be omitted by simultaneously providing the magnetic recording layer (16) with the same function as the back layer (15). Then, as shown in FIG. 3, these sheets or films can be processed into, for example, an A4 size sheet (18) having a print display portion (19), and in this case, the magnetic recording portion (20). Is the sheet (1
It can be provided only in the partial region of 8) or in the entire region.

Further, as shown in FIG. 4 (a), for example, a reversible thermosensitive recording layer (13), on a support (11),
The film provided with the protective layer (14) may be processed into a sheet shape to form a recess (23) for accommodating an IC chip and processed into a sheet shape. In this example, a print display section (19) is provided on a sheet-shaped reversible thermosensitive recording medium, and an IC chip embedding recess (2) is provided at a predetermined position on the back side of the reversible thermosensitive recording medium.
3) is formed, and in this hollow portion (23), as shown in FIG.
A wafer (231) as shown in (b) is assembled and fixed. The wafer (231) is a wafer substrate (23
2) An integrated circuit (233) is provided on the wafer substrate (232), and a plurality of contact terminals (234) electrically connected to the integrated circuit (233) are provided on the wafer substrate (232). The contact terminal (234) is exposed on the back surface side of the wafer substrate (232), and a dedicated printer (reader / writer) electrically contacts the contact terminal (234) to read or rewrite predetermined information. It is configured to be able to. One example of the function of this reversible thermosensitive recording sheet is
This will be described with reference to FIG.

FIG. 5A is a schematic block diagram showing the integrated circuit (233), and FIG. 5B is a block diagram showing an example of data stored in the RAM. The integrated circuit (233) is composed of, for example, an LSI, in which a CP capable of executing a control operation in a predetermined procedure.
It includes a U (235), a ROM (236) that stores operation program data of the CPU (235), and a RAM (237) that can write and read necessary data.
Further, the integrated circuit (233) receives the input signal and receives the CPU.
Input data to (235) and CPU (23
Input / output interface (238) for receiving the output signal from 5) and outputting it to the outside, and a power-on reset circuit, a clock generating circuit, a pulse frequency dividing circuit (interrupt pulse generating circuit), an address decoder (not shown). And circuit. The CPU (235) can execute the operation of the interrupt control routine according to the interrupt pulse that is periodically given from the pulse frequency dividing circuit. The address decoding circuit decodes the address data from the CPU (235) and gives signals to the ROM (236), RAM (237), and input / output interface (238).
A plurality of (eight in the figure) contact terminals (234) are connected to the input / output interface (238), and predetermined data from the dedicated printer (reader / writer) is input from the contact terminals (234). Output interface (2
38) and is input to the CPU (235). CPU
(235) is in response to the input signal and is in the ROM (23
6) Performs each operation in accordance with the program data stored in and outputs predetermined data and signal to the sheet reader / writer through the input / output interface (238).

As shown in FIG. 5B, the RAM (2
37) includes a plurality of storage areas (239a) to (239g). For example, the area (239a) stores the sheet number, and (239b) stores the ID data such as the name, affiliation, and telephone number of the sheet manager.
In c), for example, information about the remaining margin or handling that can be used by the user is stored, and the areas (239d) and (239) are stored.
e) For (239f) and (239g), the former manager,
Information about the previous user is stored.

Printing on the reversible thermosensitive recording medium of the present invention can be carried out by a thermal head in the same manner as in ordinary thermosensitive recording, and erasing is carried out by a temperature-controlled heat roller, a heating element such as a ceramic heater and a thermal head. Therefore, a small and simple rewriting recording device can be used, and for example, a device as shown in FIGS. 6, 7 and 8 can be provided.

In the reversible thermosensitive recording apparatus of FIG. 6, the reversible thermosensitive recording medium (1) provided with a magnetic recording layer on the opposite side of the thermosensitive layer is conveyed along a conveying path indicated by a double-headed arrow. Alternatively, it is conveyed in the opposite direction in the apparatus along the conveyance path. The reversible thermosensitive recording medium (1) comprises a magnetic head (3
4) and the carrying roller (31), magnetic recording or erasing is performed on the magnetic recording layer, and a heating process is performed between the ceramic heater (38) and the carrying roller (40) for image erasing, and the thermal head (53) and the carrying roller. An image is formed between (47) and then carried out of the apparatus. As described above, the set temperature of the ceramic heater (38) is preferably 110 ° C or higher, more preferably 112 ° C or higher, and 115 ° C.
The above is particularly preferable. However, rewriting of magnetic recording may be performed before or after image erasing by the ceramic heater. If desired, a ceramic heater (3
8) and the conveying roller (40) or after passing between the thermal head (53) and the conveying roller (47), the conveying path is conveyed in the opposite direction, and the ceramic heater (38) again performs heat treatment and thermal treatment. The printing process can be performed again by the head (53).

In the reversible thermosensitive recording apparatus of FIG. 7, the reversible thermosensitive recording medium (1) inserted from the entrance (30).
Travels along the transport path (50) indicated by a dashed line or in the opposite direction in the apparatus along the transport path (50). The reversible thermosensitive recording medium (1) inserted from the entrance (30) is conveyed in the recording device by the conveying roller (31) and the guide roller (32), and the conveying path (50).
When it reaches a predetermined position, the sensor (33) recognizes its existence through the control means (34C), and the magnetic recording or recording is erased in the magnetic recording layer between the magnetic head (34) and the platen roller (35), and the guide It passes between the roller (36) and the transport roller (37), and the guide roller (39)
An image is erased between the ceramic heater (38) and the platen roller (44) which pass between the ceramic heater (38) and the transport roller (40) and are recognized by the sensor (43) through the ceramic heater control means (38C) to operate. Therefore, the conveying roller (4) which is heat-treated for control by the rotation control means (not shown) (control of rotation speed and rotation direction including stop)
5) The thermal head (46) (47) conveys the inside of the conveying path (50), and the sensor (51) at a predetermined position recognizes its presence through the thermal head control means (53C) to operate. 53) and platen roller (5
The image is formed between 2), and the conveyance roller (59) is controlled from the conveyance path (56a) (controlled by a rotation unit (not shown)).
And it is carried out of the apparatus through the exit (61) by the guide roller (60). Reference numeral (38a) indicates a temperature sensor for the ceramic heater (38), and reference numeral (53a) indicates a temperature sensor for the thermal head (53). Here, the set temperature of the ceramic heater (38) is preferably 110 ° C. or higher, more preferably 112 ° C. or higher, and particularly preferably 115 ° C. or higher, as described above.

If desired, the transfer path switching means (55
By switching a), it leads to the transport path (56b),
The reversible thermosensitive recording medium (1) moves in the opposite direction from the operation of the limit switch (57a) that is input by pressing the reversible thermosensitive recording medium (1), and the reversible thermosensitive recording medium is controlled by the conveyor belt (58) whose rotation speed is controlled by a control means (not shown). The recording medium (1) is again loaded with the thermal head (53) and the platen roller (5).
After the heat treatment between 2), the conveying path (49b), which is communicated by switching the conveying path switching means (55b), the limit switch (57b), and the conveyor belt (48) whose rotation speed is controlled by the control means (not shown). It can be conveyed in the forward direction via the carriage and can be carried out of the carrying path (56a) through the exit (61) by the carrying roller (59) and the guide roller (60) to the outside of the apparatus. Further, such a branched conveyance path and conveyance switching means have a ceramic heater (3
8) can be provided on both sides, in which case the sensor (43) includes the platen roller (44) and the transport roller (4).
It is desirable to provide it between 5).

In the recording apparatus and recording method for the reversible thermosensitive recording medium of the present invention shown in FIG. 8, the rewriting recording apparatus detects the markings provided on both sides of the recording medium and indicating the printing direction. The recording device determines the printing direction and prints the document. The reversible thermosensitive recording (document rewriting) device of the present invention is a reversible thermosensitive recording (document rewriting).
A reversible thermosensitive recording (document rewriting) device which can use a reversible thermosensitive recording (document rewriting) medium which is a medium and can be recorded on both sides and whose recording direction is not limited on either side. Replacement) With / without a sign displayed or processed on the medium
A first signal detection mechanism that detects a non-existence and emits a sign presence / absence signal for activating the second detection mechanism when present, and operates when the sign presence / absence signal is input to identify the direction of the sign Then, the second signal detection mechanism that emits two types of sign direction signals and the first transport path that leads to the printing means when one of the two types of sign direction signals is input is opened. The transfer path switching means is closed when the other signal is input, and the energizing circuit to the printing means is shut off when the other signal is input.

That is, in the reversible thermosensitive recording (document rewriting) device shown in FIG. 8, the reversible thermosensitive recording medium (71) inserted from the insertion opening (70) is moved to the first position by the conveyor belt (73). It is conveyed along the conveying path (72) or is returned in the reverse direction in the apparatus along the first conveying path (72) or (85). A thermal head (88) as a printing means is provided in the middle of the first transport path (85). First, the reversible thermosensitive recording medium (71) inserted from the insertion opening (70) is conveyed in the recording device by the conveyor belt (73) and the guide roller (74), and is moved to a predetermined position on the first conveyor path (72). When the magnetic recording layer reaches the magnetic recording layer, the magnetic recording layer is magnetized between the magnetic head (76) and the platen roller (77) of the magnetic recording device for magnetic recording on the magnetic recording layer region portion which may be omitted via the control means (75). Recording or erasing is performed on the recording medium, and the recording medium is conveyed on the first conveying path (72) by the conveying belt (78). At a predetermined position, the control means (8
0) having a first sensor (79) as a first signal detecting mechanism, the presence / absence of a marker is detected, and when it is, a second sensor (81) having a control means (82).
The presence / absence signal of the sign for activating the is emitted. When the marker is present, it means that the first of the reversible thermosensitive recording medium (71) has already been recorded.
It means a state in which document information and signs are printed on the surface. The sign presence / absence signal is input to the second sensor (81) as the second signal detection mechanism, whereby the second sensor (81) operates to identify the direction of the sign, and as a result, 2
Emits different types of sign direction signals. One of the sign direction signals, which indicates that the reversible thermosensitive recording medium (71) is in the correct direction, activates the transport path switching means (84) by an operating means (not shown), and the control means (87). ), The first transport path (85) leading to the thermal head (88) as a printing means is opened, and the second transport path (9) is opened.
2) is closed. The other sign direction signal indicating that the reversible thermosensitive recording medium (71) is oriented in the wrong direction closes the first conveyance path (72) and the second conveyance path (9).
Open 2). Further, the other sign direction signal is input to a switch of an energizing circuit (not shown) to the thermal head (88) as a printing means to shut off the energizing circuit. The reversible thermosensitive recording medium (71) transported to the first transport path (85) is transported by the transport belt (86) and is operated at a predetermined position via the control means (87) of the thermal head. (88) and platen roller (8
An image is formed between 9) and is carried out of the apparatus via the first exit (91) by the conveyor belt (90). On the other hand, as a result of the monitoring of the sign, the second conveyance path (9
The reversible thermosensitive recording medium (71) which has already been printed with the document information and the sign on the first surface, which has been conveyed to (2), operates the limit switch (93) which is input by pressing the reversible thermosensitive recording medium (71). Is conveyed in the reverse direction by the conveyor belt (94) whose reverse speed is controlled by the control means (not shown) and whose rotation speed and direction are controlled by the control means (not shown). 84), a conveyor belt (78) whose rotation speed and direction are controlled by a control means (not shown), and a conveyor belt (73) which is similar to the conveyor belt in the opposite direction, and which is outside the apparatus through the insertion opening (70). Delivered (returned). In this way, the thermal head (88) can be used only when it is determined that the reversible thermosensitive recording medium (71) is an unrecorded medium, or when it is determined that the information recording surface and the inserting direction are correct. The energization is controlled and heated by the control means (not shown).

In the reversible thermosensitive recording (document rewriting) apparatus of the present invention shown in FIG. 8, when the reversible thermosensitive recording medium (71) is inserted in the wrong direction, it is printed by the printing means (8).
It is preferable to provide means for carrying out the apparatus from the inside of the apparatus without contacting with 8), so that the transport path switching means (84) is connected to the printing means (88).
Is provided at a branch point between the transport path (85) and the second transport path (92) that bypasses the printing unit (88) and discharges the recording medium to the outside of the apparatus. The transport end of the second transport path (92) may be connected to the first carry-out port (91) of the first transport path (72) or (85), or the first carry-out port. It may have a second carry-out port different from (91).
As described above, the second transport path (92) may be provided with means for transporting the reversible thermosensitive recording medium (71) transported therein back toward the carry-in port (70). In that case, it is not necessary to provide the second carry-out port. Furthermore, when the reversible thermosensitive recording medium (71) is inserted in the wrong direction and is guided to the second transport path (92), it is not affected by the purpose of power saving and the residual heat in the device. Therefore, the power supply circuit to the printing means (88) can be automatically cut off.

[0043]

The present invention will be described in more detail with reference to the following examples. In the examples, "parts" and "%" are based on weight. Example 1 <Preparation of recording layer> 2-anilino-3-methyl-6-dibutylaminofluorane 2 parts Developer 8 parts of the following structure

[0044]

[Chemical 7] 3 parts coloring / erasing control agent having the following structure

[0045]

[Chemical 8] 150 parts of 15% tetrahydrofuran (THF) solution of acrylic polyol resin

The above composition was pulverized and dispersed using a ball mill to an average particle size of about 1 μm. 20 parts of Coronate HL (adduct type hexamethylene diisocyanate, 75% ethyl acetate solution) manufactured by Nippon Polyurethane Industry Co., Ltd. was added to the obtained dispersion liquid and well stirred to prepare a recording layer coating liquid. The coating solution for the recording layer having the above composition was coated on a white polyester film having a thickness of 188 μm using a wire bar, and the coating was performed at 100 ° C. for 2 hours.
After drying for one minute, it was heated at 60 ° C. for 24 hours to form a recording layer having a film thickness of about 8.0 μm.

[0047] <Creation of protective layer>     Urethane acrylate UV curable resin       (Dainippon Ink and Company C7-157) 15 parts     85 parts ethyl acetate

The above composition was thoroughly dissolved and stirred to prepare a protective layer coating solution. The protective layer coating solution having the above composition was applied onto the recording layer using a wire bar and dried at 90 ° C. for 1 minute, and then passed under a UV lamp with irradiation energy of 80 W / cm at a conveying speed of 9 m / min. And cure to a film thickness of 3μ
A protective layer of m was provided to prepare a reversible thermosensitive recording medium of the present invention.

Comparative Example 1 A reversible thermosensitive recording medium was prepared in the same manner as in Example 1 except that the coloring and decoloring control agent was omitted.

Comparative Example 2 A reversible thermosensitive recording medium was prepared in the same manner as in Example 1 except that the following compound was used instead of the color-decoloration controlling agent.

[0051]

[Chemical 9]

Color density test The prepared recording medium was set in a thermal printing device manufactured by Okura Electric Co., Ltd.
Printing was performed with a voltage of 13.3 V and a pulse width of 1.2 msec, and the obtained image was measured with a Macbeth densitometer RD-914.

Erasing residual density test The color development image obtained by the color development density test is erased with a thermal gradient tester manufactured by Toyo Seiki Co., Ltd. under the conditions of 120 ° C. for 1 second, and the density and the background of the image area after the erasing are performed. The density was measured as in the color density test. Next, the erase remaining concentration was calculated from the following formula.

[0054]

[Equation 1] Unerased density = (density of image area after deletion)-
(Background density) The above results are shown in Table 2.

[0055]

[Table 2]

[0056]

As is apparent from the detailed and specific description above, the reversible thermosensitive recording medium of the present invention is excellent in erasability and color development.

[Brief description of drawings]

FIG. 1 is a diagram showing color developing / decoloring characteristics of a reversible thermosensitive recording medium of the present invention.

FIG. 2 is a diagram showing an example of the layer structure of a reversible thermosensitive recording medium of the present invention.

FIG. 3 is a diagram showing an example of a reversible thermosensitive recording medium of the present invention.

FIG. 4 is a diagram showing another example of the reversible thermosensitive recording medium of the present invention.

FIG. 5 is a diagram showing an example of use of the reversible thermosensitive recording medium of the present invention.

FIG. 6 is a diagram showing an example of a reversible thermosensitive recording apparatus of the present invention.

FIG. 7 is a diagram showing another example of the reversible thermosensitive recording apparatus of the present invention.

FIG. 8 is a diagram showing another example of the reversible thermosensitive recording apparatus of the present invention.

[Explanation of symbols]

1 Reversible thermosensitive recording medium 11 Support 13 Reversible thermosensitive recording layer 14 Protective layer 15 Back layer 16 magnetic recording layer 17 Rewrite recording section 18 sheets 19 Print display section 20 Magnetic recording unit 23 IC chip recess 231 wafers 232 wafer substrate 233 integrated circuit 234 contact terminal 235 CPU 236 ROM 237 RAM 238 I / O interface 239a to 239g storage area 30 doorway 31 Conveyor roller 32 Guide roller 33 sensors 34 magnetic head 34C control means 35 Platen Roller 36 Guide roller 37 Conveyor roller 38 Ceramic heater 38a Temperature sensor 38C ceramic heater control means 39 Guide roller 40 transport rollers 43 sensor 44 Platen roller 45 Conveyor roller 46 Conveyor roller 47 Conveyor roller 48 conveyor belt 49b transport path 50 transport paths 51 sensor 52 Platen Roller 53 Thermal head 53a Temperature sensor 53C thermal head control means 55a Transport path switching means 55b Conveyor path switching means 56a transport path 56b transport path 57a Limit switch 57b Limit switch 58 conveyor belt 59 Conveyor roller 60 guide roller 61 exit 70 insertion slot 71 Reversible thermosensitive recording medium 72 First transport path 73 Conveyor belt 74 Guide roller 75 Control means 76 magnetic head 77 Platen roller 78 Conveyor belt 79 First sensor 80 control means 81 Second sensor 82 control means 84 Conveyor path switching means 85 First transport path 86 conveyor belt 87 Control means 88 thermal head 89 Platen roller 90 conveyor belt 91 exit 92 Second transport path 93 Limit switch 94 conveyor belt

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G06K 19/00 J (72) Inventor Takeshi Shibuya 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. Inner F term (reference) 2C005 HA30 HB04 2H026 AA07 AA09 AA30 BB01 DD03 DD43 DD45 DD53 EE05 FF24 FF25 GG01 GG03 5B035 AA07 BA05 BB02 BB04 BB09 BB11 BB12 BB14

Claims (5)

[Claims] 1. A reversible sensation capable of forming a relatively colored state by using an electron-donating color-forming compound and an electron-accepting compound on a support, due to a difference in heating temperature and / or a cooling rate after heating. A reversible thermosensitive recording medium provided with a reversible thermosensitive recording layer containing a thermal composition, characterized in that a compound represented by the following formula (1) is used as a coloring and decoloring control agent in the reversible thermosensitive recording layer. Reversible thermosensitive recording medium. [Chemical 1] (In the formula, R ₁ and R ₃ each independently have 6 to 22 carbon atoms.
Is a chain hydrocarbon group, and R ₂ is a chain hydrocarbon group having 2 to 12 carbon atoms, or an aromatic group. ) 2. The reversible thermosensitive recording medium according to claim 1, comprising a thermoreversible recording section and an information storage section. 3. The information storage unit is a magnetic recording layer or I
The reversible thermosensitive recording medium according to claim 2, which is C. 4. The reversible thermosensitive recording medium according to claim 1, which is processed into a card shape. 5. The reversible thermosensitive recording medium according to claim 1, which is used in the form of a roll.