JPH04112097A - Memory card having rewritable display function - Google Patents

Abstract

PURPOSE:To impart rewritable display function to a memory card by providing a chromic layer showing color development or extinction as a display part using a volatile liquid. CONSTITUTION:A chromic layer 2 is transparent and colorless or colored at an initial stage and becomes a colored or colorless state only at a part where a volatile liquid is bonded. Many data such as a pattern, the kind of a card or an issue date are written in the design printing layer 3. A magnetic layer 5 performing magnetic recording on a base material is formed to the rear of the card and a magnetic shielding layer 6 for preventing the leakage of recording data due to a magnetic forming agent and a printing layer 7 having data such as a bar code printed thereon are formed. A card 13 is displayed by pressing a head 11 patternwise coated or impregnated with a volatile liquid along with the writing or reading to a memory card. Display is erased by the extinction of the pattern display due to natural volatilization or the instantaneous volatilization by raising temp. by a heating roller in a solvent hard to volatilize in usual environment.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a memory card mainly used as a prepaid card such as a commuter pass or a coupon ticket.

Conventional technology Conventional memory cards include magnetic recording cards and IC cards.

A magnetic recording card is constructed as a card with a ferromagnetic layer formed on a base material, and may also have a magnetic shielding layer or a surface coating layer formed as a protective layer.4 The front or back side is further printed with designs, barcodes, etc. is applied.

Although it is possible to rewrite or add information such as usage frequency, balance, and other information to the magnetic recording layer using a magnetic recording head, an IC card has an IC memory chip built into the base material, and the user's ID. Information such as codes and frequency of use is stored as electrical signals, and while this information can be rewritten and added to, it can also be used in combination with other recording methods such as magnetic recording.

Problems to be Solved by the Invention However, these records have the disadvantage that they cannot be directly viewed (this was an advantage in keeping the contents of the records secret, but in cases where display is required) For example, in telephone cards, etc., punch holes are punched to display the remaining power level, but there is a drawback that it is not possible to display a rewritable arbitrary display. Although the purpose is to provide a rewritable display function to a card, means for solving the problem In order to achieve the above object, Even if a chromic layer that shows color is provided as a display portion, a solvatochromic layer, a leuco dye-containing layer, or a charge-transfer type molecular complex forming layer is used as the chromic layer.

A chromic layer consisting of a leuco dye and a coloring agent or a chromic layer consisting of a leuco dye may also be formed as a charge-transfer molecular complex forming layer (a chromic layer consisting of an electron-accepting compound and an electron-donating compound). The rewritable memory card with a display function of the present invention (such as
The chromic layer has the above structure and can be colored or decolored by adhering a volatile liquid.In a broad sense, this coloring and decoloring also indicates discoloration of the base color of the display area. In the case of a chromic layer i', which is colored by depositing a volatile solvent in a pattern, and then discolored as the volatile solvent evaporates, consisting of a chromic dye and a coloring agent.

It is also used for thermal recording, and when the two come into contact, the color develops, and when it comes into contact with a solvent that has an affinity, the color disappears. In this colorless state, the color may regenerate as the solvent evaporates, or it may remain as it is. If the color develops again due to the volatilization of the solvent, it is possible to erase the color by attaching a volatile solvent in a pattern to the entire surface of the display area, which has been heat-sensitively colored in advance, to display the pattern. If the decolorized state is maintained even if the information is thermally recorded, the color pattern display can be decolorized with a volatile solvent to erase the display.

When a chromic layer made of leuco dye is used, it can be colored by attaching a volatile coloring liquid, and a +L proton donor or an electron-accepting compound is used as the volatile coloring liquid.

A chromic layer consisting of an electron-accepting compound and an electron-donating compound is formed when the charge transfer interaction between both compounds is weak.
In the solid state, it cannot form complexes and is colorless, but when dissolved in an organic solvent, it can form colored complexes, and when the solvent evaporates, it returns to the solid state and loses its color. By applying a volatile solvent in a pattern, the pattern can be colored and displayed.

Volatile solvents and volatile coloring liquids can be evaporated by force exchange through natural volatilization.As an active method, the solvent can be evaporated using hot air heating rollers, etc.

Embodiment First, the basic configuration and display method of the present invention will be explained with reference to the drawings.

FIG. 1 shows a schematic configuration of a rewritable memory card with a display function according to the present invention.

Here, a magnetic recording card is shown as an example of a memory card. An IC card can also have a rewritable display function with a similar configuration. In Fig. 1, 4 is a base material that supports the card;
Even if a plastic film such as polyethylene terephthalate is used, the outermost surfaces of the front side 1 and back side 8 of the card are coated with a protective coating made of a transparent plastic film. Or it is a chromic layer that shows decolorization.

In this configuration, the chromic layer is transparent and initially colorless or colored, and only the parts to which the volatile liquid is attached become colored or colorless, making the display visible. There is a lot of information written on the card, such as the type of card and the date of issue.

On the back side of the card, a magnetic layer 5 for magnetic recording is formed on the base material, a magnetic shielding layer 6 to prevent leakage of recorded information due to magnetic contrast agents, etc., and information such as barcodes are printed. By incorporating an Ic memory chip into the pattern printing layer, it is possible to create a memory card that can be used in combination with an IC card.In the present invention, a display function is provided on the back side. Memory cards can be created in many configurations depending on the purpose of the memory card and how it is used. In the present invention, we selected materials that can control the rate of volatilization.As materials with high transparency and suitable for the protective coating layer, plastics such as polyvinyl alcohol, polymethyl methacrylate, polystyrene, cellulose polymers, acrylic acid maleic acid copolymer, and nylon resin are used. The card 13 of the present invention is an example of the display method according to the present invention, in which volatile liquid is applied or laminated in a pattern. GEL erases the display even if it is displayed by pressing the impregnated head 11 against the display section. Power to naturally volatilize and eliminate the pattern display\ For solvents that are difficult to volatilize in normal environments, actively use a heated roller etc. This is done by raising the temperature to instantaneously volatilize it.

As these solvents, it is also possible to use mixed solvents, and instead of volatile liquids, it is also possible to use compounds in the solid state that play the same role.

When displaying, the compound is dissolved in a volatile organic solvent to develop or eliminate color. Or (other compounds are attached in a heated and molten state, causing color development or discoloration.

When erasing the display, the material is evaporated by heating it to a high temperature with a heating roller or the like.

The present invention is often used as an auxiliary visual display means for recorded information on a memory card, and when displaying a part of the recorded contents on a memory card, it is possible to compensate for the defects of the recording and visually display it.

Next, a specific material structure of the invention will be illustrated.

(a) Solvatochromic layer When dye molecules are dissolved in various solvents, color changes occur due to the interaction between the dye molecules and solvent molecules. For example, cyanine dyes have very high ionicity in their ground state, even if they are acids and bases.When dissolved in a highly polar organic solvent, the ground state is stabilized by the orienting force caused by electrostatic interaction. ,
The energy difference between the ground state and the excited state becomes a dog, and the absorption shifts to shorter wavelengths.

In addition, polymethine-based dark-colored merocyanine pigments or squarylium pigments, which form molecular associations in the solid state, dissolve upon contact with an organic solvent and change color to the color of the monomer4.These colors are caused by the volatilization of the organic solvent. This will restore the original color.

Compounds used as acid-base titration indicators undergo protonation or deprotonation when dissolved in or in contact with acidic or basic solvents, producing color. Specific examples of this include phenolphthalein, methyl red, p-dimethylaminoazobenzene, etc. When using a mixture of multiple of these compounds, the solvatochromic layer (Table 1) Although it can be formed by itself, it is formed by dissolving or dispersing it in plastic resin.

Such plastics (highly transparent ones are used) include polyvinyl alcohol/L=, polyethylene styrene, polycarbonate, and polymethyl methacrylate.
Leuco dye-containing layer made of cellulose-based polymers, etc. Leuco dyes are electron-donating and chemically react with organic acids or phenolic compounds. The dye is mixed with a coloring agent made of organic acids or phenolic compounds, and a volatile organic solvent such as alcohols, esters, ketones, ethers, acid amides, etc. is applied to the chromic layer of the potato. Color development is prevented only in those areas, and the display is performed by fading to a colorless area.

When the solvent evaporates and reacts again, a color develops, but
If no reaction occurs, decolorization is maintained. These reactions are determined not only by the materials of the leuco dye and coloring agent, but also by the material of the dispersing plastic, the type of volatile solvent, the dispersion particle size, the dispersion concentration, etc. Zeta-mount heating may be performed to promote the volatilization of the solvent.

The chromic layer made of leuco dye is colorless, but when a volatile coloring liquid made of organic acids or phenolic compounds is applied, the area undergoes a color reaction and displays. When the coloring liquid evaporates, it becomes colorless again, and the chromic layer (also known as chromic layer) can be formed from leuco dye and coloring agent or only leuco dye. Water-soluble and nonionic plastic materials include polyvinyl alcohol, polyethyleneoxy K, acrylic acid/maleic acid copolymers, and cellulose polymers, while those soluble in nonpolar or polar organic solvents include rubber. Examples include polymethyl methacrylate and butyral resins.They also have binding ability and are effective as binders.

Leuco Dye As the leuco dye, the leuco form (A) of a triphenylmethane dye represented by the following general formula or the leuco form (B) of a fluoran dye is used for boat fishing.

(A) Rx Ry (B) Rx, Ry, and Rz are hydrogen acid, gesalkyl group, nitro group, amino group, dialkylamino group, monoalkylamino group, allyl group, etc., and Z is necessary to form a heterocyclic ring. The atom is 0, S. As a representative example,
(A) 3.3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide [crystal violet lactone] as a compound belonging to formula (B) 3-dimethylamino-6-med as a compound belonging to formula These include oxyfluorane, 3.6-dimethoxyfluorane, and the like.

(b) Color forming agent As a color forming agent, phenolic compounds or organic acids are suitable.

Typical phenolic compounds include 4,4°-isopropylidene diphenol (so-called bisphenol A) and β-naphthol. Typical organic acids include p-oxybenzoic acid and propyl gallic acid.

C Volatile Coloring Liquid As the volatile coloring liquid, 1. Phenols, alcohols, or organic acids are suitable, and phenol, glycolic acid solution, etc. are used.

(c) Charge-transfer type molecular complex formation layer Chromic calendar method by charge-transfer type molecular complex formation Chromic calendar method composed of an electron-accepting compound and an electron-donating compound. A display part in a solid state that causes a phenomenon and does not form a complex? Q By depositing and dissolving an organic solvent in a pattern, a colored pattern due to complex formation is displayed. Then, the display disappears due to volatilization of the solvent.

The electron-accepting compound is picric acid, 1. These include aromatic nitro compounds such as 4-dinitrobenzene, and 2°5-dichloro-1,4-benzophenone.

Electron-donating compounds include diphenylamine, triphenylamine, and other aromatic hydrocarbons.AThis chromic layer can be formed from the compound alone, but even if it is dissolved or dispersed in the plastic, it is not transparent enough for the plastic material. The present invention will be explained using Examples.

Example 1 In the structure of the card shown in FIG. 1, a magnetic material layer 5, a magnetic shielding layer 6, a back printing layer 7, a back surface protective coating layer 8, and a pattern printing layer 3 were formed using polyethylene terephthalate as the base material 4. The display section 2 made of a chromic layer is formed on the recording card, and the surface is finally coated with a protective coating.First, the chromic layer material is prepared.

200 parts by weight of a 10% by weight aqueous polyvinyl alcohol solution was mixed with 35 parts by weight of crystal violet lactone as a leuco dye, and the mixture was ground and mixed in a ball mill for at least 2 hours. This dispersion liquid is called liquid A. In liquid A, the dye hardly dissolves and is dispersed in the form of fine particles of several microns or less.

Next, add bisphenol A as a coloring agent to 200 parts by weight of a 10% by weight polyvinyl alcohol aqueous solution separately from Part A.
Add 35 parts by weight and grind in a ball mill for at least 2 hours to prepare Solution B.

The coloring agent of liquid B is also dispersed as fine particles of several microns or less.

Next, weigh out 1 part by weight of Part A and 15 parts by weight of Part B and mix them in a mixer.A The resulting mixture is applied onto a card using a wire bar to obtain a chromic layer of approximately 3 microns in thickness. The layered card is heated to 100°C to 150°C using a roller to develop a uniform bluish-purple color.

Furthermore, this surface was coated with a protective coating to a thickness of about 10 microns to obtain a rewritable magnetic recording card with a display function.The display was confirmed using a silicone rubber stamp with a pattern of the 9 alphabet in an 8 mm x 8 mm square. By attaching ethyl alcohol as a volatile organic solvent, the solvent penetrates the surface protective coating layer and the area is discolored and the letters are displayed.As a result, the alphabet 2
The display of six characters was clearly observed, and the display was recolored and erased by volatilization of ethyl alcohol.Example 2 A magnetic recording card with a rewritable display function, having the same configuration as Example 1 and forming a chromic layer. First, we demonstrate the preparation of the chromic layer material.

Using 3-dimethylamino-6-medoxyfluorane as the leuco dye, prepare a solution in the same manner as Solution A in Example 1. Apply this solution on the card.A Chromic layer with a thickness of about 5 microns is obtained. .

Even worse, this surface was coated with a protective coating to a thickness of about 10 microns to obtain a rewritable magnetic recording card with a display function.A volatile coloring liquid was prepared using 1 part by weight of acetic acid to 200 parts by weight of water. Example 3: By stamping the letters, alphabets were recognized in black as in Example 1. A chromic layer was formed with the same configuration as in Example 1 to create a magnetic recording card with a rewritable display function. 1 shows the preparation of chromic layer material.

Solutions A and B were prepared in the same manner as in Example 1 using 3,6-simethoxyfluorane as the leuco dye and gallic acid ester as the coloring agent, respectively.
Mix 1 part by weight of the liquid in a weighing L mixer.

This solution was applied onto the card to a thickness of approximately 3 μm to obtain a chromic layer. This surface was then coated with a protective coating to a thickness of approximately 5 μm to obtain a magnetic recording card with a rewritable display function. using alphabet 26
The letters and numbers 0 to 9, a total of 36 characters, were colored yellow and were clearly recognizable.Using ethyl alcohol as a volatile solvent, the entire surface was brought into contact with the solvent using a roller impregnated with ethylalconyl. After volatilization, the display was erased and returned to its initial colorless state.Example 4: Characters could be displayed again using a thermal head.A solvatochromic layer was formed using the same structure as Example 1.
Polymethyl methacrylate ζ adjusted to 2% by weight using squarylium dye (C) with the following structural formula, which forms aggregates in a solid state without creating a magnetic recording card with a rewritable display function.
This solution, in which dye (C) was dissolved at a concentration of 1mM, was applied onto the card to obtain a solvatochromic layer with a thickness of about 3μm.The surface was then protectively coated with polyvinyl alcohol to a thickness of about 10μm to create a rewritable display. A functional magnetic recording card was obtained (blank below). (C) This solvatochromic layer (see below) absorbs at a wavelength of 770 nm due to the formation of aggregates of squarylium dyes and exhibits a faint color.

By attaching chloroform as a volatile organic solvent,
The solvent penetrates the surface protective coating layer, and the area changes color to blue, which corresponds to the monomer's absorption wavelength of 630 nm, and letters are displayed.9 When the solvent evaporates, aggregates are formed again, and the display changes to a faint color. Erased Example 5 With the same configuration as Example 1, an IC memory chip was incorporated into the pattern printing layer, and a chromic layer was further formed to create a magnetic recording IC card with a rewritable display function. The layer consists of a charge-transfer molecular complexing layer.

1,4-dinitrobenzene as an electron-accepting compound and diphenylamide as an electron-donating compound.

After mixing equimolar amounts of both compounds in hexane using ζ, the solvent is evaporated to obtain a mixture.

In this state, it is colorless and forms a charge transfer complex. 35 parts by weight is mixed with 200 parts by weight of a 10% by weight aqueous polyvinyl alcohol solution, and at least 2 parts by weight are mixed in a ball mill.
Grind and mix for an hour.

This solution was applied onto a card to obtain a colorless chromic layer with a thickness of approximately 5 μm.

To Zara ζ This surface is coated with a protective coating to a thickness of about 10 μm to create a magnetic recording IC with a rewritable display function.
Confirm the display using the stamp obtained on the card. By attaching hexane as a volatile organic solvent, the solvent penetrates the surface protective coating layer. The area becomes red and the letters are displayed. As a result, the alphabet 26
The letter becomes colorless again due to the clearly observed volatilization of hexane, and the display disappears.9 This coloring reaction is as shown in reaction formula (D) below.
By dissolving in a solvent and forming a charge transfer complex.

(D) Effects of the Invention As described above, in the rewritable memory card with a display function of the present invention, a chromic layer that is colored or decolored by a volatile liquid is provided as a display part on a normal memory card, so that rewritable information can be displayed. This allows for more information to be provided to the card user than with a normal memory card, expanding the range of uses.

Thus, the present invention is a dog of industrial value.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram of a rewritable memory card with a display function according to the present invention. FIG. 2 is a conceptual diagram of a display section according to the present invention. ■...Surface protection coach ink-2...Display area (chromic layer), 3...Design printing layer 4...Base material,
5...Magnetic material 6...Magnetic shielding plate 7...Back side printing 8...Surface protection coach ink', 10...
・Head support 11...pattern display head F, 12
...Visualized display section 13...Memory card with rewritable display function

Claims (8)

[Claims] (1) A rewritable memory card with a display function, which has a display section that can visualize a chromic layer that develops or decolors with a volatile liquid. (2) The rewritable memory card with a display function according to claim 1, wherein the display portion is a solvatochromic layer and is colored by applying a volatile solvent in a pattern. (3) The rewritable display according to claim 1, wherein the display part is a chromic layer made of a leuco dye and a coloring agent, and the color is erased by applying a volatile solvent in a pattern. Memory card with functions. (4) characterized in that the volatile solvent is a polar organic compound such as alcohols or esters;
The rewritable memory card with a display function according to claim 2 or 3. (5) The rewritable memory with a display function according to claim 1, characterized in that it has a chromic layer made of leuco dye as a display portion, and is colored by applying a volatile coloring liquid in a pattern. card. (6) The rewritable memory card with a display function according to claim 5, wherein the volatile coloring liquid is one of alcohols, phenols, or organic acids. (7) The rewriting according to claim 1, wherein the display part is a chromic layer made of an electron-accepting compound and an electron-donating compound, and is colored by applying a volatile solvent in a pattern. Memory card with possible display function. (8) The rewritable memory card with a display function according to claim 7, wherein the volatile solvent is either a paraffinic solvent or a chlorinated solvent.