JP2576062C - - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for directly energizing a thermal head, a laser, a flash light or an electric signal.
Thermal transfer is performed by heating the recording material according to the applied signal by means such as
Check the image recording material. 2. Description of the Related Art Changes in physical properties of materials and changes in chemical reactions in response to the application of thermal energy are taken advantage of.
As for the thermal recording method used, many methods have been proposed since ancient times. Especially
Colorless dyes such as crystal violet lactone, fluoran and spiropyran
Dyes with phenolic compounds such as bisphenol A and other organic and inorganic acids
Color reaction, organic acid metal salts and organic reducing agents such as phenols, metal sulfides, organic chelate
The transfer of inks and coloring materials to a recording medium such as paper by utilizing a thermosensitive color recording method using a thermal reaction with a thermal agent and an organic sulfur compound, and a change in thermophysical properties such as thermal fusibility and thermal sublimation.
The thermal transfer recording method has been actively studied in recent years, and efforts have been made to improve it. Especially after
The thermal transfer recording method of the user is that recording on plain paper is possible, light resistance of recorded images, etc.
Good stability and storage stability, high reliability due to simple recording mechanism, etc.
Due to its advantages, it is actively applied to printers, facsimile machines, copiers, etc.
. [Problems to be Solved by the Invention] However, in the case of a method in which a dye is thermally sublimated, the density is reproduced almost continuously.
While having the advantage of being possible, recording sensitivity, storage stability of the recording medium, fixing of recorded images
There are problems with stability, light resistance, etc. In addition, the ink is melted by heat and the
In the case of the method of transferring and recording the corresponding ink, the above problem is reduced, but usually,
Since crystalline wax having a low melting point is used as a binder for the thermal ink layer,
Problems such as reduced resolution due to thermal diffusion and weak transfer / fixed image strength
Have. In addition, crystalline waxes have light scattering in the crystalline phase, so that clear color images can be obtained.
It has the disadvantage of squeezing. Accordingly, an object of the present invention is to provide a thermal transfer recording material having good resolution.
You. Another object of the present invention is to provide a thermal transfer recording material which enables clear color reproduction.
It is to be. Still another object of the present invention is to provide a heat-sensitive transfer recording material having good recording sensitivity, transfer and fixing properties.
To provide. [Means for Solving the Problems] As a result of intensive studies, the present inventors have found that the main binder component of the thermal ink material gradient is changed to the conventional crystalline
What changed from waxes to a specific amorphous polymer and release material on the support
And further apply a main binder component from the conventional crystalline waxes to the amorphous polymer.
By applying the changed thermal ink material to a thermal ink layer,
After confirming that the object of the invention can be achieved, the present invention has been completed. That is, the present invention comprises a support and a heat-sensitive ink layer provided on one side thereof.
In the heat-sensitive recording material, the heat-sensitive ink layer is formed by laminating a plurality of heat-sensitive ink materials.
An amorphous polymer having a transfer temperature of 40 ° C. or higher and a release material as a main binder component,
The other thermal ink material comprises an amorphous polymer as a main binder component and at least one
A heat-sensitive recording material characterized in that the heat-sensitive ink material contains a colorant. In the heat-sensitive recording material of the present invention, it constitutes the main binder component of the heat-sensitive ink material immediately above the support.
The weight ratio of the amorphous polymer to the release material is 1:99 to 91: 1,
Use a substance whose melting point or softening point is 50 ° C or more and 200 ° C or less.
And a binder component of the heat-sensitive ink material that contacts at least the recording paper.
The amorphous polymer has a glass transition temperature of 40 ° C. or higher and a number average molecular weight of 10,000.
It is preferred to use: Hereinafter, the structure of the heat-sensitive recording material according to the present invention will be described in detail. Waxes conventionally used as binder materials for thermal ink materials are paraffin.
Wax, carnauba wax, montan wax, beeswax, wood wax,
Anderira wax, low molecular weight polyethylene, α-olefin oligomer and the same
These are copolymers or modified products of these, and if necessary, mineral oils such as spindle oils and oils.
Vegetable oils such as linseed oil and tung oil, dioctyl phthalate, dibutyl phthalate, etc.
Plasticizers, higher fatty acids such as oleic acid and stearic acid, their metal salts, amides and other
Derivatives are mixed and dispersed with dyes and pigments to form thin plastic films and capacitors.
It was used as a thermal transfer recording agent by applying it on paper. Since such conventional binder materials such as waxes are crystalline, the waxes should be heated at about 50 ° C.
When it has a relatively clear melting point in the temperature range of about 150 ° C and is heated above the melting point
, Rapidly changing from a solid phase to a liquid phase. And at a temperature about 30 ° C higher than the melting point,
10 ^-2 It becomes a low viscosity liquid of about 10 poise. In contrast, amorphous polymers
In this case, there is essentially no melting point, and the melting point gradually rises from the glass transition temperature (Tg).
Change from solid phase to liquid phase. The viscosity change during this period is basically determined by the WLF or
According to the Drade formula, even at a temperature about 50 ° C. higher than Tg, at most 10 ^Three ~ 1
0 ^Five The viscosity decreases only up to the poise level. In the case of thermal transfer recording, its transfer and fixing
Sensitivity is basically governed by the melt viscosity and melt viscoelasticity of the binder material.
The use of a mer as a binder for thermal inks is clearly disadvantageous in sensitivity. However, the present inventors have proposed an amorphous material having a specific molecular weight and Tg as a binder material.
Amorphous polymer and release material, and amorphous as the layer directly above the support (lowest layer)
With a thermal ink layer containing a porous polymer and a release material.
And can significantly improve image quality and image stability without sacrificing sensitivity.
Issued. The outline is described below together with a representative example. In the present invention, the binding material is gel permeation chromatography
The number average molecular weight in terms of polystyrene measured by the (GPC) method is about 10,000 or less
, Tg measured by differential scanning calorimetry (DSC) method is about 40 ° C. or more, more preferably,
Amorphous having a number average molecular weight of about 5,000 or less and a Tg in the range of about 50 ° C. to 80 ° C.
The objective can be satisfactorily achieved when a high-quality polymer or oligomer is used. When the Tg is less than 50 ° C., particularly less than 40 ° C., blocking of the heat-sensitive ink material occurs.
It is easy to occur and lacks stability during storage and use. If Tg exceeds 80 ° C
In this case, the thermal stability is good, but the sensitivity is low, so it is practical except for special applications.
Lack. If the molecular weight of the polymer is high even when Tg is within the above range,
It was experimentally confirmed that the sensitivity decreased. This is based on the entanglement of molecular chains, etc.
The number average molecular weight is about 10,000 or less, especially 5
Good transfer and fixing properties were obtained when the average molecular weight was 3,000 or less. The setting of weight average molecular weight
It can vary depending on the use of the thermal transfer recording material. Same as conventional wax-based ink
When it is desired to obtain a binary transfer image, the weight average molecular weight is about 40,000 or less, more preferably
It is desired to reduce the molecular weight distribution to about 10,000 or less. On the other hand, between polymer chains
Using the distribution of cohesive force and relaxation time, it is possible to obtain density gradation and multi-valued transferred images,
When controlling the amount of transferred ink for the purpose of repeatedly using it many times,
The average molecular weight does not necessarily need to be reduced, and may be set to about 40,000 or more. Further
Also, the molecular weight distribution pattern does not necessarily have to have a single molecular weight peak.
It is not necessary, and a distribution shape having a plurality of molecular weight peaks may be used. Also, crosslinking,
A branched polymer component may be used in combination. However, the weight average molecular weight is about 10,000 or more, especially
If it is set to 40,000 or more, it is disadvantageous in sensitivity. The chemical composition and structure of the amorphous polymer will, of course, affect the properties of the thermal ink material, but the effect is not as great as the molecular weight and Tg described above. The values of molecular weight and Tg are
If it is within the specified range, it can basically be applied as the thermal ink material of the present invention
It is. For example, styrene, vinyl toluene, α-methylstyrene, 2-methylstyrene
, Chlorostyrene, vinylbenzoic acid, sodium vinylbenzenesulfonate,
Styrene such as styrene and its derivatives, substituted homopolymers and copolymers,
Methacrylate, ethyl methacrylate, butyl methacrylate, hydroxy
Methacrylic acid esters such as ethyl methacrylate and methacrylic acid, methyl alcohol
Acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexylurea
Acrylates such as acrylates and acrylic acid, butadiene, isoprene, etc.
Diene, acrylonitrile, vinyl ether, maleic acid and maleic acid
Vinyls such as esters, maleic anhydride, cinnamic acid, vinyl chloride and vinyl acetate
A monomer alone or a copolymer with another monomer can be used. Examples of the condensation resin include phthalic acid, phthalic anhydride, isophthalic acid, and terephthalic acid.
Talic acid, hexahydrophthalic anhydride, malonic acid, succinic acid, glutaric acid, adipate
Acid, saturated dibasic acid such as sebacic acid, maleic anhydride, fumaric acid, itaconic acid
, An unsaturated dibasic acid such as tetrahydrophthalic anhydride and ethylene glycol;
-Propylene glycol, 1,6-hexanediol, bisphenol A, bis
Phenol A propylene oxide adduct, bisphenol A ethylene oxide
Polyester resins obtained by polycondensation with diols such as adducts may be used.
. In this case, trimellitic acid, glycerin, trimethylolpropane, etc.
A branched or cross-linked polyester may be formed by using a functional compound. Of course, in the case of the vinyl resin, a polyfunctional monomer such as divinylbenzene is used.
May be used as a crosslinked polymer. Furthermore, polycarbonate, polyamide
, Epoxy resin, polyurethane, silicone resin, fluorine resin, phenol
Resin, terpene resin, petroleum resin, hydrogenated petroleum resin, alkyd resin, ketone resin,
A cellulose derivative or the like may be used. These amorphous polymers or oligomers
Is used in the form of a copolymer, the copolymer may be used in addition to the random copolymer.
Depending on the purpose, a copolymerization mode such as an alternating copolymer, a graft copolymer, a block copolymer, and an interpenetrating copolymer can be appropriately selected and used. Also, two or more
When the above polymers and oligomers are mixed and used, melt mixing, melt mixing,
In addition to mechanical mixing such as marsion mixing, coexist during polymerization of polymer and oligomer components
You may mix by polymerization, a multistage polymerization method, etc. Release used as a binder material component together with an amorphous polymer or oligomer
The melting point was measured by the differential scanning calorimetry (DSC) or the ring and ball method.
Softening point is 50 ° C or more and 200 ° C or less, more preferably 60 ° C or more and 150 ° C or less
Is an organic substance or an organic / inorganic low molecular weight polymer that is solid at room temperature and has a melting point
Or a substance with a relatively low surface energy that rapidly exceeds the softening point and becomes a low-viscosity liquid.
is there. If the melting point / softening point is 50 ° C or less, storage and use stability is lacking.
When the melting point is 200 ° C. or more, the thermal energy applied by the ordinary thermal recording method is used.
-Has almost no effect on the addition. 100 ~ 180 ℃
In the temperature range, the melt viscosity rapidly drops below about 10 poise, more preferably below about 1 poise.
Low viscosity and / or critical surface tension of about 40 dyn / cm or less,
More preferably, a substance having a low surface energy of about 30 dyn / cm or less is a releasable substance.
Is effective as Specifically, for example, higher fatty acids such as palmitic acid and stearic acid;
Fatty acid metal salts such as zincate; fatty acid esters or partially saponified products thereof;
Fatty acid derivatives such as fatty acid amides; higher alcohols and polyhydric alcohols
Derivatives such as ter; paraffin wax, carnauba wax, montan wax,
Waxes such as beeswax, wood wax, candelilla wax; having a viscosity average molecular weight of about
About 1,000 to about 10,000 low molecular weight polyethylene, polypropylene,
Polyolefins such as polybutylene, or olefins and α-olefins
Water Low molecular weight with organic acids such as maleic acid, acrylic acid, methacrylic acid, vinyl acetate
Copolymer, low molecular weight oxidized polyolefin, halogenated polyolefins; lau
A product having a long alkyl side chain such as ril methacrylate or stearyl methacrylate.
Acrylates, acrylates, or acrylics with perfluoro groups
Lulic acid ester, methacrylic acid ester alone or vinyl type such as styrene
Copolymers with heavy substances; low-molecular-weight silicone resins such as polydimethylsiloxane and polydiphenylsiloxane, and silicone-modified organic substances; and long-chain aliphatic groups
A cationic surfactant such as an ammonium salt or a pyridinium salt having
Having long-chain aliphatic group, nonionic surfactant, perfluoro surfactant
One or more kinds can be selected and used from the sex agents and the like. These releasable substances melt when heated, and are used in the thermal ink material or in the thermal ink.
At the interface between the material and the support, its low cohesive strength and / or low surface energy
Based on the effect, the other binder material, amorphous polymer intermolecular and / or non-
To reduce excessive cohesion and adhesion at the interface between the crystalline polymer and the support,
It seems that the degree and image quality are improved. As described above, by using an amorphous polymer and a release material as a binder material,
Although it is possible to improve image quality and image stability, the inventors have identified multiple thermal images.
The ink material is laminated and applied on the support to form a heat-sensitive ink layer.
It has been found that image stability can be further improved. In other words, although it is more advantageous for recording sensitivity to contain a large amount of release material,
Most of the materials are crystalline materials.
Also, because of low viscosity and / or low surface energy, a recording medium such as paper
Causes the fixability of the ink to deteriorate, or the image spreads and the resolution decreases.
However, a thermal ink material using an amorphous polymer and a release material as a binder material is supported on a support.
Heat-sensitive ink material which is applied as a thin layer on top of which an amorphous polymer is used as a binder
To form a heat-sensitive ink layer, so that the function of the release material at the interface of the support is improved.
While taking advantage of the above, avoiding the obstacles caused by excessive addition of the release material, the recording sensitivity
It is possible to obtain a heat-sensitive recording material having excellent image quality and image stability. Meanwhile, release
If its content is low, its function cannot be effectively exhibited. Also release on the support
A thermal ink material with a conductive material as a binder is applied, and an amorphous polymer is
When a thermal ink material is used as the landing material, the release
Thermal ink material between the support and the thermal ink material and / or laminated
The adhesiveness between the materials decreases, and the thermal ink layer peels off and falls off before use. Amorphous polymer as binder in thermal ink material first applied to support
The heat-sensitive recording material of the present invention is most effective when used in a weight ratio of about 1:99 to 99: 1, particularly preferably about 10:90 to 90:10, with respect to the release material.
You can achieve your aim. Also, a releasable substance is added to the second and subsequent thermal ink materials applied to the support.
Then, it is also possible to utilize the function. In addition, when the release material and other ink materials such as an amorphous polymer are mixed, a chemical bond is formed.
May occur. In particular, in order to improve the dispersibility of the release material, an amorphous polymer
Stabilization of dispersion by utilizing the reaction and interaction between the active groups of
I can do it. In addition, in the presence of a release material, an amorphous polymer monomer is superposed.
In this case, the amorphous polymer and the release material are grafted or polymerized by condensation polymerization.
It is also effective to disperse them. Examples of the coloring agent in the heat-sensitive recording material of the present invention include carbon black and oil black.
Black dyes such as racks and graphite; C.I. I. Pigment Yellow1,
Acetoacetate arylamide monoazo yellow face family (3, 74, 97, 98, etc.)
Fast yellow); C.I. I. Pigment Yellow 12, 13,
Azoacetate arylamide-based disazo yellow pigments such as 14; I. Solven
t Yellow 19, 77, 79, C.I. I, Disperse Yellow
yellow dyes such as w. I. Pigment Red 48, 49: 1, 5
Red or red pigments such as 3: 1, 57: 1, 81, 122, and 5; I.
Red dyes such as Solvent Red 52, 58 and 8; I. Pigme
Blue dyeing of copper phthalocyanine such as nt Blue 5: 3 and its derivatives and denatured products
Pigments and other conventional printing inks, such as colored or colorless sublimable dyes, etc.
Well-known dyes and pigments can be used for coloring purposes. These dyes and pigments may be used alone or in combination of two or more. Of course
Alternatively, the color tone may be adjusted by mixing with an extender or a white pigment. Furthermore, a binder material
In order to improve the dispersibility of the components, the surface of the colorant
Embedded with a coupling agent such as a coloring agent, a polymer material, or a polymer dye or polymer
Soft pigments may be used. In the heat-sensitive recording material of the present invention, in addition to the above, a charge control and / or antistatic agent,
Conductive agent, antioxidant, thermal conductivity improver, magnetic substance, ferroelectric substance, preservative, fragrance, antiblocking agent, reinforcing filler, release agent, foaming agent, sublimable substance, infrared absorber, etc.
May be added to the inside or outside of the thermal ink material. As a support, polyester such as polyethylene terephthalate, polyimide
And plastic films such as imide copolymers, fluorine polymers, polypropylene, etc.
Thin sheets and films such as films and condenser papers are conveniently used. These sheets, films, or rolls have thermal conductivity and heat stability inside
Add thermal property modifier, release agent, antistatic agent, conductive agent, and reinforcing agent to improve the properties
May be used. When recording is performed using a thermal head, etc., the thermal head of the support is used.
To improve heat resistance, running properties, etc., use silicone-based or fluorine-based
A compound, a resin layer, a crosslinked polymer layer, a metal layer, a ceramic layer, or the like may be provided.
Further, the film internal additive may be added to the outer layer. The surface of these supports is smooth
Alternatively, an uneven portion, a groove, or the like may be provided. Also, even if it is porous
Good. The thermal transfer recording material of the present invention comprises an amorphous polymer or oligomer and a release material.
A plurality of thermal ink materials mixed with a colorant, and, if necessary, various additives described above.
It is formed by laminating a coating material on a support. Mixing the thermal ink material can dissolve and / or stably disperse the binder material
Form a solution and / or dispersion emulsion in a solvent and / or dispersion medium;
Preparation with a mixing and dispersing machine such as a mill, sand mill, attritor, three rolls, etc.
Can be. Also, without using a solvent or the like, a three-roll heating die,
The solvent may be mixed using a hopper, a Banbury mixer, or the like. Furthermore, colorant, addition
Amorphous polymers and oligomers as binder components are superposed in the presence of
In combination, a thermal ink material may be used. A plurality of thermal ink materials prepared in this way are coated on a support with a gravure coater.
And / or a melt coating method using a wire bar or the like.
Or printed. Further, the thermal ink material is powdered by a spray drying method, a pulverizing method, etc.
The support may be powder-coated by an electrocoat method or the like. In this case, powder coat
Thereafter, if necessary, heating, pressurizing, solvent treatment and the like are further performed, and the heat-sensitive powder ink may be fixed on the support and used. Furthermore, when preparing such a heat-sensitive powder ink,
In the presence of colorants, additives, release materials, etc.
Powder inks by polymerizing the polymer by direct polymerization methods such as suspension polymerization method and dispersion polymerization method
May be. Further, as a support, an electrothermal conversion element having a structure similar to a thermal head
Alternatively, a light-to-heat conversion element may be directly used, and a heat-sensitive ink layer may be provided thereon. The thickness of the support film, sheet, and thermal ink layer are appropriately selected according to the application.
The thickness of the support is generally about 1 μm to about 200 μm.
It's easy to do. In order to improve the resolution, the thickness is preferably from about 1 μm to about 10 μm. The thermal ink layer has a dry coating thickness of each thermal ink material of about 0.1 μm depending on the application.
Set to about 50 μm, usually in the range of about 0.5 μm to about 20 μm
Easy to use. Further, a plurality of types of ink materials having different physical properties may be dividedly coated in the plane layer. The heat-sensitive recording material thus formed is heated, laser, flash,
Heated in response to the applied signal by means such as direct application of light or electric signal,
Flip against recording media such as paper and film in contact or non-contact state
Thereby, the thermal ink material is transferred and recorded. To improve recordability,
In addition to mechanical force such as pressure and foaming, electric field, magnetic field, ultrasonic wave, solvent, etc. can be used together
is there. EXAMPLES Hereinafter, the present invention will be described with reference to examples, but the present invention is of course limited by these examples.
It is not something to be done. In the following examples, parts are by weight unless otherwise specified.
You. Example 1 Kneaded in a ball mill for 40 hours, and heat-sensitive ink materials (a) to
(H) was created. 20 parts of thermal ink with solid composition shown in Table 1 80 parts of toluene The heat-sensitive ink materials (a) to (h) obtained in this manner were structured as shown in Table 2 below.
Sequentially coated on a 6μm thick polyester film by wire bar coating
The cloth was dried to prepare thermal ink materials 1 to 14. The structure of the heat-sensitive ink material is as follows.
Those provided with an ink layer 2 (first layer) (No. 1 to No. 3 and No. 13 to No. 1)
4) and the polyester film shown in FIG.
Ink layer 3 (first layer) and thermal ink layer 2 (No. 4 to No. 12)
is there. The representative recording characteristics of these heat-sensitive recording materials 1 to 14 were measured by Fuji Xerox Co., Ltd.
Table 3 shows the results of evaluation using an FXP-6 thermal transfer printer. The recording characteristics were evaluated by the following method. Recording sensitivity: Equivalent to thermal head heating element size (1/8 mm = 125 μm)
Energy applied to the thermal head required to record a transfer dot (= E) A: E <0.7 mJ / dot ○; 0.7 mJ / dot < E <0.9 mJ / dot Δ; 0.9 mJ / dot < E <1.1 mJ / dot ×; 1.1 mJ / dot < E Resolution: How to break Chinese characters (especially those with a large number of strokes) Transparency: Turbidity of color when transferred and recorded on an OHP sheet onto a screen Degree of fixation: Ink when rubbed with fingers and eraser Peeling off and stains around the transferred image
Strength of raw ink layer: peeling state of ink in areas other than image area generated at the time of recording As shown in Table 3, the conventional type (No. 1) using wax as a binder was used for recording.
Excellent sensitivity, but kanji with a large number of strokes may cause character collapse and transfer
Hard rubbing of the image with a finger caused smeared ink rubbed around the transfer image
. On the other hand, when only the amorphous polymer is used as the binder and no release material is contained (No.
.2 and 3) are higher in resolution, transparency and fixability of the transferred image than the conventional type (No. 1).
Although the width has been improved, the recording sensitivity is relatively low, and
In the case where the releaser uniformly contained the release material (Nos. 13 and 14),
The transfer sensitivity is improved compared to the case of using only the polymer (Nos. 2 and 3),
Since the releasable substance was contained in the whole ink layer, there was a problem in transparency. Ma
When only the release agent was used as the binder of the first layer (No. 8, 11), the binder was not
The transfer sensitivity was improved as compared with the case of using only the amorphous polymer (Nos. 2 and 3).
When there is a problem with the strength of the ink layer and care must be taken when handling the thermal recording material
was there. The thermal transfer recording materials (Nos. 4 to 7, 9) according to the present invention have recording sensitivity almost equal to that of the conventional type.
As a result, a clear print without crushing was obtained. Also, the transparency of the transferred image
And the fixability slightly vary depending on the content of the release material in the first layer, but this is a practical problem.
No.7, which has the highest content, is much more excellent than the conventional type (No.1), and the recording sensitivity is improved by increasing the content.
Content can be selected. Furthermore, the effects of controlling the number average molecular weight Mn and the glass transition temperature Tg of the amorphous polymer are
Confirmed from the relationship between No. 4 and No. 10, No. 8 and No. 11, and No. 9 and No. 12.
Was done. Example 2 Kneaded in a ball mill for 40 hours, and heat-sensitive ink materials (i) to
(J) was created. [Thermal Ink Material Composition] (i) Polyester Resin (J) Styrene / dimethylaminoethyl methacrylate copolymer (same as in Example 1 ink (g)) 7 parts Oleic acid monoglyceride 3 parts Toluene 90 parts From these heat-sensitive ink materials (i) and (j), To make a thermal recording material
The recording characteristics were evaluated. That is, first, a thermal ink material (j) was formed on a 3.5 μm thick polyester film.
Is applied with a wire bar so that the ink layer thickness after drying is 0.5 μm, and dried.
Thermal ink material (i) is also applied as a first layer and then as a second layer on the same.
Apply with an ear bar so that the ink layer thickness after drying is 2.0 μm, dry and apply heat
The recording forest fee was No. 15. The thickness of the ink layer must be 2.5 μm for the first and second layers.
did. As a result of the evaluation of the recording characteristics, it was about 1.1 times that of the conventional type (Example 1, heat-sensitive recording material No. 1).
With the applied energy of the thermal head, there is no crushing and the outline is clear,
A strong print which did not cause any problem was obtained. The image transferred to the OHP sheet had good transparency, and when projected onto a screen, a bright blue projected image without turbidity was obtained. Example 3 A thermosensitive ink material (k) having the following composition was mixed and dispersed using an attritor.
Created. [Thermal ink material composition] The resulting thermal ink material (k) is used as a first layer to form a 3.5 μm thick
Coated on an ester film to a dry thickness of 0.5 μm, and heat-sensitive in Example 2.
The colorant of the ink material (i) was changed to a red pigment (Cl. Pigment Red 57: 1).
) Or a yellow pigment (CI Pigment Yellow 2)
A thermosensitive coating applied on the first layer dried as the second layer to a dry thickness of 3.0 μm.
Recording materials No. 16 and 17 were used. The recording characteristics were evaluated in the same manner as in Example 1.
And strong printing with excellent transparency. Example 4 From the heat-sensitive ink materials (i) and (j) of Example 2, a heat-sensitive recording material having the structure shown in FIG.
It was created. That is, a thickness of 15 μm and a volume resistivity of 10 ⁰ Ωcm conductive polycarbonate net
Aluminum of the support 6 in which aluminum 5 is vacuum-deposited on one side of the
The ink layer thickness after drying the thermal ink material (j) on the nickel surface becomes 0.5 μm
And dried with a wire bar to form a first layer 3 and then a second layer 2 thereon
The ink layer thickness after drying the heat-sensitive ink material (i) with a wire bar is also 5.0 μm.
m and dried to obtain a thermal recording material oblique No. 18. This heat-sensitive recording material No. 18 was mounted on a prototype energized heat-sensitive transfer type printer.
When recording on various types of recording paper, bond paper with low smoothness, plain paper (high quality paper)
A strong mark that has a very clear outline and does not cause ink peeling due to rubbing, etc.
I got a character. Example 5 First Layer Coated with Thermal Ink Material Containing Release Material and Polymer (Lower Layer:
Recording sensitivity and transparency of thickness and release material content of base film)
The effect on was evaluated. The prescription of the heat-sensitive recording material used in the evaluation was as described in Example 1 above (a), (e) and
And (g), with respect to the thickness of the ink layer, a heat-sensitive ink material containing a release material.
Coatings (a) and (e) are each applied in various thicknesses to form a first layer and then a second
Layer (thermosensitive ink material (g)) is applied, and the total dried ink layer thickness of the two layers is 3.0.
μm (the first layer having a thickness of 0 is the one coated with only g).
You. ). FIG. 4A shows the relationship between the thickness of the first layer and the recording sensitivity, and FIG.
4 shows the relationship between layer thickness and transparency. When the first layer is formed by applying a thermal ink material containing a release material,
The sensitivity is sufficiently improved if the thickness of the first layer is about 1.0 μm,
Even if the first layer was thickened, there was no effect of improving the recording sensitivity (see FIG. 4 (a)). On the other hand, the transparency suddenly deteriorated when the ink layer thickness was about 1.5 μm (FIG. 4 (b)
)reference). In addition, the higher the content, the greater the effect of improving the recording sensitivity.
On the contrary, the transparency was easily deteriorated, and the same tendency as the ink layer thickness was shown.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing the structure of a conventional thermal transfer recording material, and FIGS. 2 and 3 are cross-sectional views each showing the structure of a thermal transfer recording material according to the present invention. FIG. FIGS. 4 (a) and 4 (b) are graphs showing the relationship between the thickness of the first layer, the recording sensitivity, and the transparency of a recording material coated with a thermal ink material having a release material and a polymer as the first layer. It is. Symbols in the drawing: 1 ... polyester film; 2, 3 ... thermal ink layer; 4 ... conductive polycarbonate film; 5 ... aluminum layer; 6 ... support.

Claims (1)

11. Claims 1. A heat-sensitive recording material composed of a heat-sensitive ink layer provided support and on one side thereof, which heat sensitive ink layer was laminated two heat sensitive ink material, 2 Among the kinds of thermal ink materials, the thermal ink material immediately above the support is an amorphous polymer having a glass transition temperature of 40 ° C or higher and 80 ° C or lower and a melting point or softening point of 50 ° C or higher.
A layer having a thickness of 1.5 μm or less containing a release material at a temperature of 200 ° C. or less as a main binder component, and other thermal ink materials mainly comprising an amorphous polymer having a glass transition temperature of 40 ° C. to 80 ° C. A heat-sensitive recording material, wherein at least one heat-sensitive ink material contains a coloring agent as a coloring component. 2. The method according to claim 1, wherein the weight ratio of the amorphous polymer and the release material constituting the main binder component of the thermal ink material directly on the support is 1:99 to 99: 1.
2. The heat-sensitive recording material according to item 1. 3. The heat-sensitive recording material according to claim 1, wherein the number- average molecular weight of the amorphous polymer , which is a binder component of the heat-sensitive ink material that contacts at least the recording paper, is 10,000 or less.