JPH05124343A - Reversible thermal recording material - Google Patents

Abstract

PURPOSE:To provide a reversible thermal recording material where data can be thermally recorded and deleted reversibly and which has excellent recording performance and image contrast. CONSTITUTION:A polyester polymer sheet 1 has an aluminum-evaporated reflecting layer 2 formed using 0.6g of eicosandicarboxylic acid and 0.4g of amid stearate as an organic crystal particle 6 and 3g of a vinyl chloride/vinyl acetate copolymer as a matrix polymer 5. In addition, a recording layer 3 with a thickness of 10mum is formed on the polyester polymer sheet 1 and further, a surface coated layer 4 is formed. The recording characteristics of this recording medium are such that the transparent temperature range is about 80 to 110 deg.C, thus enabling data to be recorded stably and the MacBeth optical density is 0.7 or higher allowing an image to be recorded in satisfactory contrast. Also no characteristic change occurs, if data is deleted or rerecorded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reversible thermosensitive recording material capable of reversibly recording and erasing by heating, such as a memory card with a rewritable display function used as a prepaid card such as a commuter ticket, ticket, and coupon ticket. , IC card,
It is most effective when used as recording paper for facsimiles.

[0002]

2. Description of the Related Art Conventional reversible thermosensitive recording materials include thermosensitive dye recording materials that reversibly develop and decolor by a combination of a leuco dye and a color developer and a decolorizer, and organic crystals in a matrix polymer. Utilizing the melting and solidification behavior of particles, the phase change type reversible thermosensitive recording material that utilizes the change in transparency of particles depending on the solidification conditions, and the thermal behavior of its molecular arrangement mainly by liquid crystal polymers such as cholesteric liquid crystals There is a method to change transparency by using it.

The present invention relates to a phase-change type heat-sensitive recording material which utilizes the melting and solidification behavior of organic crystal particles in a matrix polymer and changes in the transparency of the particles depending on the solidification conditions. Fine particles are melted and solidified again by the condition, and the transparency of the solidified morphology (polycrystalline state, single crystalline state, amorphous state, etc.) is changed depending on the condition, and recorded. This heat-sensitive recording material is disclosed, for example, in JP-A-54-1.
As disclosed in 19377, it is composed of a combination of a matrix polymer and the following fusible organic molecules, and can form an extremely wide variety of recording materials. The fusible organic molecules disclosed herein include aliphatic and aromatic alcohols, carboxylic acids, amines, amides and their halides, sulfides, and the like. On the other hand, as the matrix polymer, polyester, polyamide, polyacrylic acid, styrene, silicone, polyvinyl chloride,
Common polymers such as polyvinylidene chloride and polyacrylonitrile are disclosed. In addition, a recording material that improves this by further adding carbon black and an antioxidant,
It is disclosed in JP-A-57-82087 and 57-82088.

However, in these compounds which have been studied in many cases, the storage temperature of recording is inferior because the transparency temperature is relatively low and is in the range of several tens of degrees Celsius, and the width thereof is narrow as several degrees Celsius. There was a problem that there was no margin. For example, behenic acid having a carbon number of 22 (melting point of 80, which is a typical straight-chain saturated fatty acid capable of obtaining high resolution and contrast)
(° C) is used as the fusible organic molecule, and in the reversible thermosensitive recording material in combination with the vinyl chloride / vinyl acetate copolymer,
The clearing temperature range was about 68 ° C. to 74 ° C., and the width was narrow at about 6 ° C., and it was difficult to perform stable recording.

As a method for improving such a low transparency temperature and a narrow temperature range, there is a method of forming an organic crystal particle by mixing an aliphatic dicarboxylic acid with a higher fatty acid having 16 or more carbon atoms, and Japanese Patent Laid-Open No. 2-1363. , Japanese Patent Laid-Open No. 3-2089. In JP-A-2-1363, a dicarboxylic acid having 4 to 16 carbon atoms or a derivative thereof is added to a higher fatty acid in a weight ratio of 95: 5 to 20:80, and both molecules are eutecticized to obtain a temperature range. In JP-A-3-2089, an aliphatic dicarboxylic acid having 20 or more carbon atoms is added to a higher fatty acid in a weight ratio of 95: 5 to 50:50 to expand the temperature range by eutecticizing both molecules. is doing. As for their characteristics, the clearing temperature was 100 ° C. or lower, and the temperature range was several degrees Celsius to 20 ° C. at most.

[0006]

However, when a recording medium made of a reversible thermosensitive recording material is used, stable recording and stable retention of the recorded information can be achieved by controlling the temperature control stability of the recording heat source. Considering factors such as the margin and the normal operating environment temperature, there is a need for a material in which the transparency temperature is raised to a higher temperature range to widen the transparency temperature range.

Therefore, an object of the present invention is to provide a reversible thermosensitive recording material having a high transparency temperature, a wide temperature range, an excellent recording resolution and a high contrast by constructing a novel organic crystal particle. It is in.

[0008]

The present invention provides a saturated fatty acid monoamide having organic hydrocarbon particles having a hydrocarbon chain of 12 or more carbon atoms, a saturated fatty acid bisamide having a hydrocarbon chain of 12 or more carbon atoms, and 12 or more carbon atoms. And at least one aliphatic compound selected from urea compounds substituted with a hydrocarbon chain, and an aliphatic dicarboxylic acid represented by the general formula HOOC (CH ₂ ) _n COOH (where n is an integer of 14 to 24) And the mixture ratio of both is 6 by weight.
In the range of 0:40 to 10:90, a reversible thermosensitive recording material in which the organic crystal particles are dispersed in a matrix polymer is constituted to solve the conventional problems and achieve the above object.

[0009]

The reversible thermosensitive recording material of the present invention comprises a saturated fatty acid monoamide having a hydrocarbon chain of 12 or more carbon atoms and 1 carbon atom.
A saturated fatty acid bisamide having two or more hydrocarbon chains, and at least one selected from urea substituted with a hydrocarbon chain having 12 or more carbon atoms, and an aliphatic dicarboxylic acid having two hydrogen-bonding groups are mixed. The organic crystal particles thus contained are dispersed in a matrix polymer made of a thermoplastic transparent polymer.

When an aliphatic dicarboxylic acid is dispersed alone in a matrix polymer to form a recording medium, it is difficult to form a uniform recording layer. However, as a result of repeated studies, when forming the recording layer, a film-forming method of drying in a thermostat set at 100 ° C. or higher, and a heat treatment as an intermediate layer of an anchor effect when forming the recording layer on the substrate were used. It has been found that a uniform recording layer can be formed by using a medium structure formed through a plastic transparent resin,
It has become possible to obtain the characteristics that the transparency temperature is high and the width of the transparency temperature region is wide, but the white turbidity is poor and it is difficult to obtain a good contrast. The present invention provides a reversible thermosensitive recording material having good recording characteristics by utilizing the characteristics of an aliphatic dicarboxylic acid by forming organic crystal particles in which an aliphatic dicarboxylic acid and another organic crystalline molecule are mixed. Is.

In the present invention, as a result of extensive studies on many organic compounds as organic crystal particles of a reversible thermosensitive recording material, with respect to recording sensitivity and recording characteristics, the melting point of the organic crystal particles and an organic compound having a hydrogen-bonding group were found. It has been found that the number and type of hydrogen bonding groups in the molecule is important. Furthermore, as a result of investigating the effect of hydrogen bonding interaction, a fatty acid amide having a strongly polar acid amide group involved in two hydrogen bonds, or a long chain having a strongly polar urea group involved in three hydrogen bonds It has been found that substituted ureas of the hydrocarbon chain show excellent properties when mixed with an aliphatic dicarboxylic acid. These fatty acid amides and aliphatic substituted ureas have high crystallinity because of strong association between molecules due to strong sterically generated hydrogen bonds, and have high crystal strength, and have a particularly high melting point among aliphatic compounds. In particular, when the aliphatic long chain is a saturated hydrocarbon chain, it is difficult to dissolve in various organic solvents.

In the case of a recording material using an aliphatic dicarboxylic acid alone, since it has two hydrogen bonding groups, a strong bond such as a hydrogen bond is likely to cause association, and the melting point is high. It is considered that the area becomes higher, but conversely, with respect to the contrast, the compatibility with matrix polymer is large, so the compatibility becomes too high, the crystal grain size becomes fine, it is difficult for white turbidity, and the transmittance change is small. ..

In the present invention, in addition to the aliphatic dicarboxylic acid, a saturated fatty acid monoamide having a hydrocarbon chain of 12 or more carbon atoms, a saturated fatty acid bisamide having a hydrocarbon chain of 12 or more carbon atoms, and a carbonization of 12 or more carbon atoms. By dispersing organic crystal particles mixed with at least one aliphatic compound selected from urea substituted with hydrogen chains in the matrix polymer, a high contrast and a wide transparentization temperature range can be realized. That is, although it is not known exactly yet, due to the strong hydrogen-bonding property of these aliphatic compounds, when they are mixed with an aliphatic dicarboxylic acid and eutecticized with each other, intermolecular interaction is enhanced, and association or complex formation occurs. By forming a complex such as a mixed crystal or a eutectic crystal, many crystal forms are greatly contributed, a wide clearing temperature can be obtained due to the difference in temperature characteristics of each form, and a plurality of crystal forms can be obtained. It is considered that since it is a complicated microcrystal, white turbidity is improved and high contrast can be obtained. In addition, since fatty acid amides such as fatty acid monoamides and fatty acid bisamides and aliphatic substituted ureas are hardly soluble in a solvent when forming a recording layer, they are eutectic with an aliphatic dicarboxylic acid in a solution and at the same time ultrafine particles are formed. It is considered that they are dispersed as and serve as crystal nuclei in the organic crystal particles. And, since the melting point of these crystal nucleus portions is high, it is considered that the effect as the crystal nucleus works up to a high temperature temperature in the process of melting and crystallization of the organic crystal particles, and it is possible to have a high and wide transparentization temperature region. Be done.

[0014]

EXAMPLE FIG. 1 shows a conceptual cross-sectional view of the constitution of the reversible thermosensitive recording material of the present invention. The recording layer 3 of the present invention is formed on the polymer sheet 1 having the reflective layer 2 formed by aluminum vapor deposition. A wear-resistant surface coat layer 4 is further formed on the recording layer 3. The recording layer 3 is, as shown in FIG.
The organic crystal particles 6 in the matrix polymer 5 include a matrix polymer 5 made of a thermoplastic transparent polymer having a hydrogen bonding group and organic crystal particles 6, and the heating and cooling process causes the organic crystal particles 6 in the matrix polymer 5 to be:
Transparent state 6A and opaque white turbid state 6B (light scattering state)
There are two states. This corresponds to erasing / recording.

The organic crystal particles 6 of the present invention contain a mixture of an aliphatic dicarboxylic acid and at least one selected from saturated fatty acid monoamide, saturated fatty acid bisamide, and urea substituted with a hydrocarbon chain. The aliphatic dicarboxylic acid has the general formula HOOC (CH ₂ ) _n COOH (provided that n
Is an integer of 14 to 24), which has carboxyl groups at both ends of the hydrocarbon chain, and has good crystallinity because intermolecular hydrogen bonds are generated at both ends of the molecule, and the melting point is as high as 120 ° C. or higher. A relatively high clearing temperature is obtained, which is preferable. In the formula, n (length of hydrocarbon chain) is the organic crystal particle 6
Of the melting point of the organic crystal particles 6, the interaction of hydrogen bonds in the organic crystal particles 6, and the solubility of the organic crystal particles 6 in the matrix polymer 5,
A proper length is selected from the dispersibility of the organic crystal particles 6 in the matrix polymer 5.

The aliphatic compound mixed with the aliphatic dicarboxylic acid has at least one acid amide group or urea group as a hydrogen bonding group, and the length of the hydrocarbon chain is an aliphatic dicarboxylic acid group. It is preferable that the length is almost the same as that of the acid, it is easy to form a complex, and the melting point is satisfied.
It is preferably 2 or more. As the compound, saturated fatty acid monoamide, saturated fatty acid bisamide, and substituted urea of the hydrocarbon chain can obtain excellent properties. As typical compounds, saturated fatty acid monoamide is lauric acid amide (melting point 86 ° C.), palmitin. Acid amide (same 100 ° C), stearic acid amide (same 101 ° C), behenic acid amide (same 1)
10 ° C), hydroxystearic acid amide (same 110)
C), N-stearyl stearamide (94)
C), N-stearyl oleic acid amide (at 67 ° C.),
Saturated fatty acid bisamides such as oleyl stearic acid amide (at the same temperature of 74 ° C), methylol stearic acid amide (at the same temperature of 111 ° C) and methylol behenic acid amide (at the same temperature of 110 ° C) are methylenebisstearic acid amide (at the same temperature of 143 ° C) and ethylenebislauric acid. Amide (same 157 ° C), ethylenebisstearic acid amide (same 143 ° C), ethylenebishydroxystearic acid amide (same 144 ° C), hexamethylenebisstearic acid amide (same 146 ° C), N,
N'- distearyl adipic acid amide (at 144 ° C),
m-xylene bisstearic acid amide (at 123 ° C.),
N, N'-Distearylisophthalic acid amide (same as 129
, Etc., such as hydrocarbon chain-substituted urea include N, N′-distearylurea (the same 114 ° C.), stearylurea, xylenebisstearylurea (the same 163 ° C.), and diphenylmethanebisstearylurea (the same 210 ° C.). .. These are materials that are industrially used as lubricants for resins, sensitizers for heat-sensitive recording paper, antiblocking agents for toner, etc., and have low toxicity, and are suitable for recording materials for direct contact with consumers. ..

In order to obtain excellent recording performance, the mixing ratio of the aliphatic dicarboxylic acid and the saturated fatty acid monoamide, the saturated fatty acid bisamide, and at least one aliphatic compound selected from the substituted urea of the hydrocarbon chain is set to a mixing ratio. is important. As the mixing ratio, the ratio of the aliphatic compound and the aliphatic dicarboxylic acid to be mixed in the weight ratio is preferably 60:40 to 10:10.
When it is 90, excellent recording performance can be obtained. When the proportion of the aliphatic dicarboxylic acid is higher than the composition ratio, the eutectic mixture with the aliphatic compound to be mixed is small and the complex portion does not act, so that high contrast cannot be obtained. On the contrary, when the ratio of the aliphatic compound to be mixed is more than the range of the above composition ratio, the aliphatic compound becomes difficult to eutectic with the aliphatic dicarboxylic acid, and the excess aliphatic compound is separated and precipitated in the matrix. As a result, the homogeneity of the recording layer deteriorates, the contrast deteriorates, and the transparentization temperature region also narrows.

On the other hand, in general, the matrix polymer 5 includes polyester, polyacrylic ester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, cellulose acetate, polyvinyl butyral, polystyrene, styrene.
There are butadiene copolymers and the like, and the behavior of the matrix polymer 5 is largely different depending on the combination with the organic crystal particles. As the matrix polymer 5 used in the present invention, as shown in FIG. 2, a hydrogen-bonding group-containing thermoplastic transparent polymer gives a good effect. The reason is that a hydrogen-bonding group existing in the vicinity of the interface of the organic crystal particle 6 which is a composite,
This is because the interaction with the hydrogen bonding groups contained in the matrix polymer 5 causes the melting / solidifying behavior to be different from that of the organic crystal particles 6 made of a single compound, and the behavior of transparency change also changes. Adhesiveness (containing OH groups) as a specific example of matrix polymer having hydrogen bonding groups
Polyester, partially saponified vinyl acetate-vinyl chloride copolymer, polyamide, polyurethane, thermoplastic phenol resin, vinyl alcohol copolymer, acrylic acid copolymer, acrylamide copolymer, maleic acid copolymer, etc. are suitable. .. Further, since the recording material of the present invention is a thin film, a considerable transparency can be obtained. Further, it goes without saying that a plasticizer may be used in the recording layer of the present invention in a timely manner.

The organic crystal particles 6 constituting the reversible thermosensitive recording layer 3 are added in an amount of 5 to the matrix polymer 5.
It can be added in the range of 60%, but addition of 15 to 30% is desirable. If the ratio of the organic crystal particles 6 is more than this, the binding force is weakened and it becomes difficult to uniformly coat the recording layer 3. On the contrary, when the ratio of the matrix polymer 5 is high, the amount of the organic crystal particles 6 is small, so that it becomes difficult to make the opaque and the contrast of recording is deteriorated.

The recording medium using the reversible thermosensitive recording material of the present invention is a recording medium having a high durability against repeated contact with a thermal head when the abrasion-resistant surface coating layer 4 is provided. can do. This recording medium can be written and erased in a heat mode not only by a thermal head but also by a laser. A heat roller may be used for erasing.

Further, the surface coating layer 4 as shown in FIG. 1 is not essential for the reversible thermosensitive recording medium of the present invention,
For the recording medium of the present invention in which recording and erasing are repeatedly performed by a thermal head or a heat roller, it is preferable to provide the surface coat layer 4 because thermal deformation does not occur during recording and erasing. As the material for the surface coat layer 4, a transparent resin of ultraviolet ray or heat-curing type such as acrylic resin can be applied, and it is cured by a conventional method according to the curing mode of the resin after coating.

The present invention will be described below with reference to examples. (Example 1) As organic crystal particles 6 of a reversible thermosensitive recording material, aliphatic dicarboxylic acid was HOOC (CH ₂ ) ₁₈ COO.
0.6% of H-eicosandicarboxylic acid (melting point 127 ° C)
and 0.4 g of stearic acid amide (melting point: 101 ° C.). In addition, matrix polymer 5
Using 3 g of vinyl chloride / vinyl acetate copolymer as
It is mixed and dissolved in 15 g of tetrahydrofuran, coated on a 0.2 mm polyester polymer sheet 1 having the aluminum vapor-deposited reflective layer 2 shown in FIG. 1, dried in a thermostat at 100 ° C., and then a recording layer having a thickness of 14 μm. Formed 3. A reversible heat-sensitive recording sheet was prepared by coating a prepolymer of an ultraviolet-curable acrylic resin as a wear-resistant surface coating layer 15 on the recording layer 3 in a thickness of 15 μm and then curing by irradiating with ultraviolet rays. Writing and erasing were performed on this reversible thermosensitive recording sheet with a thermosensitive head. The clearing temperature region of this sheet was about 80 to 110 ° C, and the clearing temperature range was about 30 ° C. From this condition, energy is applied by the thermal head to write at 115 ° C and turn cloudy.
When erased and made transparent at 00 ° C, clear recording characteristics were obtained. By the evaluation with the Macbeth optical density, a contrast of 0.73 was obtained, and good recording could be recognized.
Further, the life characteristics were measured repeatedly, and it was able to withstand more than 500 times.

As a comparison, in the reversible thermosensitive recording medium in which 0.7 g of eicosandicarboxylic acid and 0.3 g of stearic acid amide are mixed to form organic crystal particles, the transparentization temperature range is about 80 to 85 ° C. The temperature range was as narrow as 6 ° C., the transparency was poor at the time of transparency, and the repetition was about tens of times.

Example 2 As the organic crystal particles 6 of the reversible thermosensitive recording material, the aliphatic dicarboxylic acid was HOOC (C
H ₂ ) ₁₄ COOH hexadecanedicarboxylic acid (melting point 1
23 ° C.) and ethylene bisstearic acid amide (melting point 143 ° C.) of 0.1 g were mixed and configured. Furthermore, vinyl chloride / vinyl acetate copolymer partially saponified as matrix polymer 5 (hydroxyl group ratio about 5%)
0.2 g of 3 g of the aluminum vapor-deposited reflective layer 2 shown in FIG. 1 was formed by mixing and dissolving it in 15 g of tetrahydrofuran.
m on polyester polymer sheet 1 at 120 ° C
A recording layer having a thickness of 10 μm was formed after drying in a constant temperature bath. The recording layer 3 was further coated with a prepolymer of a UV-curable acrylic resin as a wear-resistant surface coat layer 15 to a thickness of 15 μm, and then irradiated with UV rays to be cured.

Writing and erasing were performed on the reversible thermosensitive recording sheet thus formed by a thermosensitive head. As for the recording characteristics, stable recording can be performed at a transparentization temperature range of about 85 to 113 ° C. and a width of about 23 ° C.
The above good contrast could be obtained.

Example 3 As the organic crystal particles 6 of the reversible thermosensitive recording material, the aliphatic dicarboxylic acid was HOOC (C
H ₂ ) ₁₆ COOH octadecanedicarboxylic acid (melting point 1
(25 ° C.), and xylene bisstearyl urea (melting point 163 ° C.) 0.3 g were mixed and configured. Further, using 3 g of vinyl chloride / vinyl acetate copolymer resin as the matrix polymer 5, 15 g of tetrahydrofuran
Was mixed and dissolved in to prepare a stock solution of the recording material. As the thermoplastic transparent polymer of the intermediate layer 8, a vinyl chloride / vinyl acetate copolymer resin was used, and 0.3 g of the vinyl chloride / vinyl acetate copolymer resin was dissolved in 12 g of tetrahydrofuran to form the aluminum vapor deposition reflective layer 2. An anchor layer having a thickness of 2 μm was formed on a polyester polymer sheet 1 having a thickness of 0.2 mm. Further, after drying, the stock solution of the recording material is applied on the anchor layer and dried in a constant temperature bath at 150 ° C.
A recording layer 3 having a thickness of μm was obtained. A reversible heat-sensitive recording sheet was prepared by coating a prepolymer of an ultraviolet-curable acrylic resin as a wear-resistant surface coating layer 15 on the recording layer 3 in a thickness of 15 μm and then curing by irradiating with ultraviolet rays.

Writing and erasing were performed on this reversible thermosensitive recording sheet by a thermosensitive head. The clearing temperature range of this sheet was about 78 to 110 ° C, and the clearing temperature range was about 32 ° C. Under this condition, energy was applied by the thermal head to write at 115 ° C and erase at 100 ° C, and clear recording was performed.

Example 4 As the organic crystal particles 6 of the reversible thermosensitive recording material, the aliphatic dicarboxylic acid was HOOC (C
H ₂ ) ₂₀ COOH eicosandicarboxylic acid (melting point 12
0.4g, stearic acid amide (melting point 101)
(.Degree. C.) and 0.3 g of docosanol (melting point 70.degree. C.). Furthermore, 3 g of partially saponified vinyl chloride / vinyl acetate copolymer (hydroxyl group ratio about 5%) was used as the matrix polymer 5 and mixed and dissolved in 15 g of tetrahydrofuran to prepare a stock solution of the recording material. A reversible thermosensitive recording sheet was prepared in the same manner as in Example 1.

Writing and erasing were performed on this reversible thermosensitive recording sheet with a thermosensitive head. The clearing temperature range of this sheet is about 75 to 95 ° C, and the clearing temperature range is about 2
It was 1 ° C. Under this condition, energy was applied by a thermal head to write at 100 ° C and erased at 90 ° C, clear recording was performed, and repeated life characteristics were measured. Was done.

[0030]

As described above, the present invention includes a polymer composition in which organic crystal particles are dispersed in a matrix polymer,
The organic crystal particles are selected from saturated fatty acid monoamide having a hydrocarbon chain having 12 or more carbon atoms, saturated fatty acid bisamide having a hydrocarbon chain having 12 or more carbon atoms, and urea substituted with a hydrocarbon chain having 12 or more carbon atoms. At least one and a general formula HOOC (CH ₂ ) _n COOH (where n is 1
An integer of 4 to 24) and a mixture of the aliphatic dicarboxylic acid and the component ratio of both of them in the range of 60:40 to 10:90 by weight, and by dispersing the organic crystal particles in the matrix polymer. , A reversible thermosensitive recording material whose transparency reversibly changes depending on the heating temperature, solves the conventional problems, and has a wide and high clearing temperature region, which provides high recording margin and high contrast. In addition to the above, there is an effect of having excellent recording characteristics with high reliability.

The recording sheet having the reversible thermosensitive recording material of the present invention formed on a polymer sheet can be widely used as a reversible thermosensitive recording sheet for writing / erasing with a thermosensitive recording head or a laser. As described above, the present invention has great industrial value.

[Brief description of drawings]

FIG. 1 is a conceptual cross-sectional view showing the configuration of an embodiment of a recording medium made of the reversible thermosensitive recording material of the present invention.

FIG. 2 (a) is an enlarged cross-sectional view of an essential part showing a state of transparent organic crystal particles in a reversible thermosensitive recording material according to an embodiment of the present invention. (B) is a reversible thermosensitive recording according to an embodiment of the present invention. Enlarged sectional view showing the state of opaque organic crystal particles in the material

[Explanation of symbols]

 1 Polymer Sheet Base Material 2 Reflective Layer 3 Recording Layer 4 Surface Coat Layer 5 Matrix Polymer 6 Organic Crystal Particles 6A Transparent Organic Crystal Particles 6B Opaque White Crystalline Organic Crystal Particles 7 Interfacial Interaction Area

Claims (2)

[Claims] 1. A recording material containing a polymer composition in which organic crystal particles are dispersed in a matrix polymer, wherein the organic crystal particles have a saturated fatty acid monoamide having a hydrocarbon chain having 12 or more carbon atoms, and a saturated fatty acid monoamide having 12 or more carbon atoms. At least one aliphatic compound selected from saturated fatty acid bisamides having a hydrocarbon chain and urea substituted with a hydrocarbon chain having 12 or more carbon atoms, and a general formula HOOC (CH ₂ ) _n COOH (where n is A reversible thermosensitive recording material comprising a mixture with an aliphatic dicarboxylic acid represented by the formula (14 to 24) and the mixing ratio of the mixture is in the range of 60:40 to 10:90 by weight. 2. The reversible thermosensitive recording material according to claim 1, wherein the matrix polymer is a thermoplastic polymer having a hydrogen bonding group.