JP3219300B2 - Thermal transfer recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a heat fusible ink layer on a support, and particularly, has a storage stability under a low temperature and prevents an image receptor, that is, a receptor paper, from being stained on a thermal head. More particularly, the present invention relates to a thermal transfer recording medium having excellent print quality, which is suitable for a barcode, and prevents peeling of an ink layer when not used at a low temperature. (Bar code printed on ゜) relates to a thermal transfer recording medium with clear printing.

[0002]

2. Description of the Related Art In recent years, thermal transfer recording systems using thermal heads have been reported to be noise-free, to make devices relatively inexpensive and compact, to be easy to maintain, and to have stable printed images. It has come to be used frequently due to its advantages. Representative examples of the thermal transfer recording medium employed in such a thermal transfer recording system include: (1) a thermal fusible ink layer comprising a colorant and a binder provided directly on a support; The ink layer is formed by laminating a first ink layer on the support side and a second ink layer. The first ink layer is mainly composed of wax, the second ink layer is mainly composed of a colorant and a binder. And those provided on a support.

However, the binder of the ink layer (heat-meltable ink layer) of (1) and the binder of the first ink layer of (2) are mainly composed of wax having low plasticity. In addition, the adhesiveness to a resin film such as PET (polyethylene terephthalate), which is often used as a support, is extremely low, and a disadvantage occurs that the heat-meltable ink layer is peeled off from the support by mechanical external force. This phenomenon appears remarkably especially at a low temperature (for example, about 5 ° C.) and a humidity of about 10 to 50% RH.

In order to eliminate such inconvenience, the surface of the support is made uneven to increase the contact area between the ink layer and the support (Japanese Patent Laid-Open No. 58-16889). An intermediate adhesive layer made of a cellulosic resin, a polyester resin, or the like is provided therebetween (JP-A-59-165).
690, Japanese Unexamined Patent Publication No. 60-54894, etc.) have been proposed, but have the drawback that the manufacturing method and process become complicated, leading to an increase in manufacturing cost.

Further, an ink layer (the ink layer of the above (1),
Since the binder of the first ink layer and the second ink layer (2) is mainly composed of wax having low plasticity, the adhesive strength of the ink layer is low, and as a result, a serial bar code is not used in a bar code printer or the like. When printing is performed, a drop phenomenon (a phenomenon in which a portion to which energy is not applied by the thermal head is transferred together) occurs, resulting in unclear printing. Therefore, a situation may occur in which the barcode scanner cannot read the barcode.

Further, it is hard to say that the barcode image obtained by the conventional thermal transfer recording medium has sufficient friction resistance.
That is, it is often recognized that when a thermal transfer image is rubbed with, for example, corrugated paper or the like, the barcode is disturbed and cannot be read. In recent line printers, a thermal head up / down mechanism has been added in order to increase the printing speed or reduce the consumption of the thermal transfer recording medium. Along with this, there has been a problem that the receiving paper is stained at the start or end of high-speed printing or when the head is moved up and down.

[0007]

SUMMARY OF THE INVENTION A first object of the present invention is to improve the adhesion of an ink layer, to improve the storability, especially the storability at low temperatures, to eliminate the phenomenon of dropping, and to provide a thermal head. An object of the present invention is to provide a thermal transfer recording medium which prevents contamination of receiving paper and the like generated during operation and improves image quality, and is particularly suitable for bar code printing. Another object of the present invention is to provide a thermal transfer recording medium which is excellent in abrasion resistance of an image and does not cause stain on a receiving paper.

[0008]

Means for Solving the Problems In a thermal transfer recording medium in which a heat-meltable ink layer and an overcoat layer are sequentially provided on a support, the heat-meltable ink layer mainly contains a colorant, a wax and a rubber elastomer. , yet the rubber elastomer is being allowed to be present in and intermittently dispersed lamellar, overcoat layer is characterized in that the elongation at 40 ° C. to 60 ° C. consisting of 5% or less of the heat fusible substance.

The inventors of the present invention have conducted intensive studies and studies to achieve the above object, and as a result, the rubber elastomer in the hot-melt ink layer was allowed to exist in a specific state and the overcoat layer was formed in a specific state. It has been found that this can be achieved by including the material. The present invention has been completed based on these findings.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. 1A and 1B show an ink layer 104 a or 104 b according to the present invention on a support 102.
FIG. 3 is a schematic view of two examples showing a state in which an overcoat layer 120 is formed. Here, the ink layer 104a
Is a single layer, but the ink layer 104b is the first ink layer 1
06 and an ink layer 108. In the figure, 112 indicates a rubber solid, 114 indicates a coloring agent, and 116 indicates a heat-fusible material.

The heat-fusible material in the single ink layer 104a of FIG. 1A is mainly composed of wax or wax and a binder resin. In the heat fusible material 116 in the stacked ink layers 104b of FIG. 1B, the first ink layer 106 is mainly composed of wax, and the second ink layer 108 is mainly composed of binder resin. Although it is possible to use a binder resin to some extent as the heat-fusible material 116 of the first ink layer 106, this layer 106 has a release function for easily transferring the second ink layer 108 to recording paper. Rather, relying solely on the wax gives better results. On the other hand, the second ink layer 1
As the hot-melt material 08, not only the binder resin but also a wax is used in combination with the binder resin, so that a better result is obtained.

A first feature of the thermal transfer recording medium of the present invention is that
That is, the rubber elastomer 112 is dispersed and contained in the ink layer 104a or the first ink layer 106 in a layered and discontinuous state. The shape and thickness of the rubber elastomer 112 are not always constant. However, as shown in FIG. 2, the plate-like rubber elastomer (solid material has a thickness (T) of 0.02-0.5 μm and a width (W) of 0.20-5.
It is about 5 μm. The rubber elastomer 112 has a structure in which at least two or more plate-like rubber elastomers 112 'are laminated so as to mainly sandwich at least wax. Here, "at least the wax is sandwiched" means that, for example, in the ink layer 104a of FIG. 1A, a part of the binder resin or the coloring agent other than the wax can enter between the plate-like rubber elastomers. This is because of the nature. The layer interval (G) when the plate-like rubber elastomer 112 'is in the form of a layer is 0.01 to 0.5.
It is about 4 μm (FIG. 3).

FIG. 4 is a schematic view showing a state in which some of the rubber elastomers 112 are dispersed and contained in the ink layer. These are mainly composed of a plurality of plate-like rubber elastomers 112 ′ in common. It is in a form of being laminated via a wax layer 116 '. However, the plate-like rubber elastomer 112 'does not necessarily have to be entirely flat, but may be partially curved or entirely curved. Furthermore, a large number of plate-like rubber elastomers 112 ′ are vertical,
The width and height dimensions need not all be equal, but rather differ naturally.

As will be apparent from the examples described later, when adding the rubber elastomer to the coating liquid, a method in which a rubber elastomer component is added to a liquid in which a composition material excluding the rubber elastomer is dispersed in advance and mixed by stirring, or after mixed molten components other than water, hot water is pre-emulsified added under stirring, and emulsified under high pressure, the regulated wax emulsion solids adjusted by quenching with water, the way of mixing the rubber latex From the above, a coating liquid for forming an ink layer is prepared, applied, and obtained by drying at a temperature capable of maintaining a state in which the rubber elastomer is layered and intermittently dispersed in the ink layer. According to the thermal transfer recording medium containing and dispersing the discontinuous rubber elastomer 112 ',
Good quality thermal transfer images can be obtained. The present inventors have further researched to enhance the effect, and as a result,
Under the range of 50% RH, the adhesive strength is 1.5 to 3.5 gf.
/ Cm, it was confirmed that a better quality thermal transfer recording medium could be obtained.

FIG. 5 is an explanatory view of the Tensilon tensile compression tester, which is shown in a longitudinal section. The model used was TCM-200CR type manufactured by Minebea. Here, a method for measuring the shearing force and the adhesive force using this tester will be described.

In the figure, reference numeral 1 denotes a thermal transfer recording medium, and 2 denotes an adhesive tape (Nichiban Co .: Cellotape 18m).
m × 35 mm), and the adhesive surface of the adhesive tape 2 faces the ink layer 104a or 104b. 102b is a support layer. Reference numeral 3 denotes a reinforcing plate, in which case a thick stainless steel plate was used. 4 is a fixture. In the measurement method, the thermal transfer recording medium 1 adhered with the adhesive tape 2 was peeled off at a constant speed, and the state was observed. The measurement conditions are as follows. Peeling angle: 180 ° Peeling speed: 50 mm / min Specimen width: 10 mm Test environment temperature: 5 ° C, 35% RH and 20 ° C, 60%
RH

Here, the shear strength refers to the ink layer 104a.
Alternatively, when only 104b remains on the adhesive tape 2 and is peeled off, it is a force applied when peeling is started, and the adhesive strength is a force applied when peeling.

The thermal transfer recording medium of the present invention is shown in FIG.
And (b) a heat-resistant and / or slip-protective layer may be provided on the back surface of the support 102 (the surface of the support in contact with the thermal head). The heat-resistant and / or lubricating protective layer is provided if necessary. By providing this, the heat-resistant and / or lubricating property of the support 102 can be improved, and it can be used conventionally. This makes it possible to use a support material that has not been used.

Examples of the support 102 include plastic films having relatively high heat resistance, such as polyester, polycarbonate, triacetyl cellulose, nylon, and polyimide, as well as glassine paper, condenser paper, and metal foil. The length is about 2 to 15 μm, preferably 3
About 10 μm.

Examples of the material of the heat-resistant and / or lubricous protective layer include silicone resin, silicone rubber, modified silicone resin, fluorine resin, polyimide resin, epoxy resin, phenol resin, melamine resin, nitrocellulose and the like. .

The ink layer 104a is a heat-meltable layer, and contains a colorant, a wax, a rubber elastomer, or a binder resin as a main component.

The colorant is appropriately selected from conventionally known dyes and pigments.

Examples of the wax include paraffin wax, microcrystalline wax, paraffin wax, candelilla wax, carnauba wax, montan wax, ceresin wax, polyethylene wax, polyethylene oxide wax, caster wax, tallow hardened oil, lanolin, wood Waxy substances such as wax, sorbitan stearate, sorbitan palmitate, stearyl alcohol, polyamide wax, oleylamide, stearylamide, hydroxystearic acid, synthetic ester wax, and synthetic alloy wax. It is desirable to use a wax having a penetration of 2% or less under the conditions of 25 ° C. and 60% RH, and carnauba wax is particularly effective.

When a wax and a binder resin are used,
Examples of the binder resin include polyamide-based, polyester-based, polyurethane-based, vinyl chloride-based, cellulose-based, petroleum-based, styrene-based, butyral-based, and phenol-based resins, as well as ethylene-vinyl acetate copolymers and ethylene-acrylic resins. Resins.

The rubber elastomer has a shear strength of the ink layer 104a or 104b of 25 to 45 gf /
cm and an adhesive strength of 1.5 to 3.5 gf / cm. Here, as the rubber elastomer, for example, butadiene rubber, styrene-butadiene rubber, nitrile rubber, nitrile-butadiene rubber,
Synthetic rubbers such as styrene-isoprene rubber, isoprene rubber, acrylic rubber, epichlorohydrin rubber, butyl rubber, and ethylene-propylene rubber, and natural rubber are exemplified.

The weight ratio of each material constituting the ink layer 104a is suitably about 5 to 50/30 to 90/5 to 50/3 to 30 = colorant / wax / binder resin / rubber elastomer.

As the ink layer 104a, a known plasticizer such as a fatty acid ester, a glycol ester, a phosphoric ester, or an epoxidized linseed oil, or an oil may be added in a small amount (30% or less). Absent.

The ink layer 104a is applied while distributed in a solvent, can be formed by drying, the thickness thereof is 1 to 10
μm, preferably 2 to 6 μm (FIG. 1A). If the thickness of the ink layer 104a is less than 1 μm, insufficient density or lack of printing on paper having relatively low smoothness occurs.
If it exceeds 0 μm, the adhesive strength will be reduced, and the ink layer will peel off at a low temperature. In addition, if the thickness of the ink layer 104a is too large, the shear strength increases, which may result in poor transfer.

Next, the ink layer 104b is the first ink layer 1
A thermal transfer recording medium (FIG. 1B) of a type configured by laminating the second ink layer 108 and the second ink layer 108 will be described.

As mentioned above, the first ink layer 106 is composed of a wax as the heat-fusible material 116 and a rubber elastomer (which can be intermittently dispersed in a layer form).
112 is formed as a main component.

The wax used here is 40 to 100 ° C.
Paraffin wax, microcrystalline wax, oxidized paraffin wax, candelilla wax, carnauba wax, montan wax, ceresin wax, polyethylene wax, polyethylene oxide wax, caster wax, tallow hardened oil, lanolin, wood wax, sorbitan steer having a melting point of Wax, sorbitan palmitate, stearyl alcohol, polyamide wax, oleylamide, stearylamide, hydroxystearic acid, synthetic ester wax, synthetic alloy wax, and the like. Among them, the penetration at 25 ° C is 2 or less. Is preferred, and desirably carnauba wax. This is because the friction resistance of the printed image surface is improved by using wax with high hardness,
This is advantageous for maintaining a reliable barcode image. Among these waxes, carnauba wax is particularly preferably used.

The rubber elastomer 112 and the wax are exactly the same as those described in the description of the ink layer 104a. In addition, the presence of the rubber elastomer 112 is such that the first ink layer 106 and the second ink layer 108 together have a shear strength of 25 to 45 gf / cm at 5 ° C. and an adhesive strength of 1.5 to 3.5 gf / cm. It is preferable to express.

When the shear strength is less than 25 gf / cm and the adhesive strength is less than 1.5 gf / cm at 5 ° C., peeling of the ink layer occurs at low temperature (5 ° C.) and at room temperature (20-25 ° C.). Also, when a serial barcode is printed by a barcode printer, a dropout phenomenon occurs and the barcode scanner cannot read the serial barcode.

On the other hand, the shear strength is 45 gf at 5 ° C.
If the adhesive strength is greater than 3.5 gf / cm and the adhesive strength is greater than 3.5 gf / cm, the adhesive strength to the support becomes greater than the adhesive strength to the transfer receiving paper, resulting in poor transfer.

The weight ratio of each material constituting the first ink layer 106 is as follows: wax / rubber elastomer = 95 to 75/5
~ 25 is appropriate.

As the first ink layer 106, other than these, if necessary, polyvinyl butyral, vinyl chloride-
Vinyl acetate copolymer resin, nitrocellulose, epoxy resin, ethylene-vinyl acetate copolymer resin, ethylene-α-
One or more resins such as olefin copolymer resins, α-olefin-maleic anhydride copolymer resins, ethylene-methacrylic acid copolymer resins, and ethyl cellulose may be mixed in appropriate amounts.

The thickness of the first ink layer 106 is 0.5 to 10
μm, preferably 1-3 μm. 0.5 μm thick
If the thickness is smaller, the function as a release layer is reduced, and the transferability to paper having relatively small smoothness is deteriorated. In addition, thickness is 10μ
If it exceeds m, the adhesive strength decreases and the ink layer peels at a low temperature (5 to 10 ° C.). In addition, if the thickness of the release layer 106 is too large, the shear strength increases, which may result in poor transfer. Further, by using a specific heat-meltable ink wax, the abrasion resistance of an image can be improved. The second ink layer 108 contains a coloring agent, a binder, and wax as main components. Second ink layer 108
Has a thickness of 0.5 to 4 μm, preferably 1 to 3. Furthermore, the weight ratio of the colorant and the binder resin as a main component of the layer 108 is 5: 95 to 20: Ru much 80 suitable der.
The first ink layer 106 can be formed by the same means as described for the ink layer 104a. Ma
And, second ink layer 108 is similar to the first ink layer 106
Or dissolved in a hot melt or solvent
It can be formed by coating and drying.

A second feature of the present invention is that a specific heat-fusible substance is used as a component of the overcoat layer. The overcoat layer in FIGS. 1 (a) and 1 (b) enables the transfer medium to be obtained without causing stain on the non-printed portion of the recording paper. According to
We shall later metal material tensile test method (JIS Z2241) by the elongation consists of heat-fusible substance is 5% or less are particularly suitable for printing clearly the serial code has been found.

<Measurement method of elongation percentage> A hot-melt substance formed into a dumbbell shape as shown in FIG. 6 is used. This is set as shown in the figure, and it is pulled in the direction of the arrow and its elongation is set to Y. . Tensile speed: 1 mm / min Load converter: wa × 5 Kgf or wa × 200 Kgf The elongation is obtained by the following equation. Y / L x 100 = elongation (%)

Examples of such a heat-meltable substance having an elongation of 5% or less include carnauba wax, rice wax, terpene resin, styrene resin, and aliphatic saturated hydrocarbon resin.

The thickness of the overcoat layer formed mainly of such a heat-fusible substance is 0.01 to 5 μm, preferably 0.01 to 2 μm. If it is less than 0.01 μm, the effect of preventing contamination is poor, and if it exceeds 5 μm, the transfer of the hot-melt ink is impaired, which is not preferable.

Further, the overcoat layer according to the present invention may contain a lubricant or a surfactant as an auxiliary component. Lubricants include petroleum-based lubricating oils such as spindle oil, machine oil, engine oil, gear oil, mapin oil, polyolefin, polyglycol, polyphenyl ether, dihydrochloride ester, neopentyl polyol ester, phosphate ester, polyester Chlorofluoroethylene,
Examples include synthetic lubricating oils such as fluoroesters, silicone compounds, and silicone resins. Surfactants include fatty acid salts, alkyl sulfate salts, alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl sulfosuccinates, alkyl dienyl ether disulfonates, alkyl phosphates, polyoxyethylene alkyl allyls Anionic surfactants such as sulfate esters, cationic surfactants such as alkylamine salts and quaternary ammonium salts, amphoteric surfactants such as alkyl hetines and amine oxides, and polyoxyethylene alkyl ethers and polyoxyethylene alkyls Allyl ether, polyoxyethylene derivative, oxyethylene / oxypropylene block polymer, sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, glycerin fatty acid ester, polio Shiechiren fatty acid esters, nonionic surfactants such as polyoxyethylene alkyl amines, etc., there are various things, these fluorine-based, the silicon-based, also include those of acetylenic.

[0043]

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples. In addition, all the parts and% shown below are based on weight.

Example 1 A polyethylene terephthalate (PE) having a thickness of about 5.5 μm
T) Using a wire bar, apply a coating solution of the following component A on a film so that the thickness after drying is about 3.5 μm;
The ink layer was dried at 60 ° C. to form an ink layer. (A component) Carnauba wax 60 parts Candelilla wax 13 parts 5% toluene solution of polybutadiene rubber 240 parts (Nippon Synthetic Rubber Co., Ltd .: JSR BR 31) Carbon black (Mitsubishi Kasei Kogyo Co., Ltd .: MA-7) 15 parts Toluene 492 parts Methyl isobutyl ketone 180 parts In addition, the preparation of the coating solution of the component A was carried out by heating and mixing a composition excluding polybutadiene rubber (5% toluene solution) in advance and then performing ball milling at room temperature for 12 hours to obtain a dispersion. Subsequently, a polybutadiene rubber (5% toluene solution) was added to the dispersion under stirring. Furthermore, a coating liquid comprising the following A 'component is dried thereon to a thickness of about 1 μm.
m and dried at 45 ° C. to form an overcoat layer. (A 'component) Carnauba wax (3% elongation) 20 parts Rice wax (5% elongation) 6 parts Dispersant 4 parts Water 70 parts

Example 2 A polyethylene terephthalate (PE) having a thickness of about 5.5 μm
T) Applying a coating solution of the following component B on a film using a wire bar so that the thickness after drying is about 1.5 μm;
It was dried at 55 ° C. to form a first ink layer. (B component) Carnauba wax 88 parts 5% toluene solution of polybutadiene rubber 240 parts (Nippon Synthetic Rubber Co., Ltd .: JSR BR 31) Toluene 492 parts Methyl isobutyl ketone 180 parts In the same manner as in Example 1, the composition excluding the rubber component was dispersed in advance, and the rubber component was added thereto. Further, a coating liquid comprising the following component C was applied thereon using a wire bar so that the thickness after drying was about 2 μm, and dried at 70 ° C. to form a second ink layer. (Component C) Carnauba wax aqueous dispersion (solid content 30%) 183 parts Candelilla wax aqueous dispersion (solid content 30%) 67 parts Ethylene-vinyl acetate copolymer aqueous dispersion (solid content 30%) 33 parts Aqueous dispersion of carbon black (solid content 30%) 75 parts Surfactant (Rhodol TW-S120 manufactured by Kao Atlas Co., Ltd.) 1 part Water 61 parts Methanol 80 parts And dried to form an overcoat layer.

Example 3 A thermal transfer recording medium was prepared in exactly the same manner as in Example 2 except that the component B was changed to the following component D. (D component) Carnauba wax 70 parts Paraffin wax (Nippon Seiro Co., Ltd .: HNP-16) 19 parts 5% toluene solution of polybutadiene rubber 160 parts (Nippon Synthetic Rubber Co., Ltd .: JSR BR 31) Toluene 511 parts Methyl isobutyl ketone 180 parts

Example 4 A thermal transfer recording medium was produced in exactly the same manner as in Example 2 except that the component B was changed to the following component E. (Component E) Carnauba wax 70 parts Montan wax (Hoechst: HoechsI-Wax KP) 17 parts 5% toluene solution of polybutadiene rubber 5 parts (Nihon Gosei Zeon Corporation: Higol BBR 1220) 5% of acrylonitrile-butadiene rubber Toluene solution) 100 parts (Nippon Synthetic Rubber Co., Ltd .: JSR N234L) Polystyrene resin 5% toluene solution 60 parts (Esso Standard Oil Co., Ltd .: D125) Toluene 568 parts Methyl isobutyl ketone 180 parts

Example 5 A polyethylene terephthalate (PE) having a thickness of about 4.5 μm
T) A coating solution of the following F component is applied on a film using a wire bar so that the thickness after drying is about 1.5 μm,
The first ink layer was formed by drying with hot air at 60 ° C.

(F component) Carnauba wax emulsion (solid content 30%) 1) (average particle size 1.04 μm) 150 parts butadiene rubber latex (solid content 50%) (JSR # 0700, manufactured by Nippon Synthetic Rubber Co., Ltd.) 10 parts water 90 parts Further, a coating liquid comprising the following G component was applied thereon using a wire bar so that the thickness after drying was 1.4 μm, and dried at 70 ° C. to form a second ink layer. Formed.

(G component) Carnauba wax emulsion 2 below (solid content 30%) (average particle size 0.224 μm) 250 parts ethylene-vinyl acetate copolymer latex (solid content 30%) (Sumikaflex 410 manufactured by Sumitomo Chemical Co., Ltd.) 33 parts Carbon black aqueous dispersion (solid content 20%) 75 parts Surfactant (Reodol TW-S120) 1 part Water 61 parts Methanol 80 parts

[Preparation of Carnauba wax emulsion] Carnauba wax emulsion 1) Carnauba wax 27 parts Nonionic emulsifier (HLB14) 3.0 parts Water 70.0 parts

After the components except water were mixed and melted at 90 ° C., the remaining hot water was added with stirring and pre-emulsified with a disperser. Thereafter, the mixture was emulsified with a high-pressure homogenizer and quenched with water. The average particle size was 1.04 μm.

Carnauba wax emulsion 2) Carnauba wax emulsion 1) was prepared in the same manner as 1) except that the emulsifier of 1) was an anionic (HLB13) emulsifier and pre-emulsification was sufficiently performed with a disperser.
The average particle size was 0.224 μm. Also in Example 6 and thereafter, 1) for the first ink layer and 2) for the second ink layer.
An emulsion was prepared in the same manner as described above. Further, a coating solution comprising the component A 'was applied thereon under the same conditions and dried to form an overcoat layer.

Example 6 A thermal transfer recording medium was produced in exactly the same manner as in Example 5 except that the component F of Example 5 was replaced with the following H component. (H component) Carnauba wax: Candelilla wax = 7: 3 mixed wax emulsion (solid content 30%) (average particle size 1.95 μm) 155 parts Styrene-butadiene rubber latex (solid content 50%) 7 parts ( (JSR0561 manufactured by Nippon Synthetic Rubber Co.) 88 parts of water

Example 7 A thermal transfer recording medium was produced in exactly the same manner as in Example 5 except that the component F in Example 5 was replaced with the following component I. (I component) Carnauba wax: Lanolin derivative synthetic wax = 9: 1 mixed wax emulsion (solid content 30%) (average particle size 2.10 μm) 155 parts Carboxy-modified acrylonitrile butadiene latex (solid content 50%) (JSR0910) Nippon Synthetic Rubber Co., Ltd.) 10 parts Water 85 parts

Example 8 A thermal transfer recording medium was obtained in exactly the same manner as in Example 5 except that the G component in Example 5 was replaced with the following J component. (Component J) Carnauba wax emulsion (average particle size 2.29 μm) (solid content 30%) 183 parts Candelilla wax emulsion (average particle size 0.18 μm) (solid content 30%) 67 parts ethylene-vinyl acetate copolymer Combined latex (solid content 30%) (Sumikaflex 401 manufactured by Sumitomo Chemical Co., Ltd.) 33 parts Carbon black aqueous dispersion (solid content 20%) 75 parts Surfactant (Reodol TW-S120) 1 part Water 61 parts Methanol 80 parts

Example 9 A thermal transfer recording medium was obtained in the same manner as in Example 6, except that the following K component was applied as a second layer on the first ink layer of Example 6. (K component) Carnauba wax / terpene resin (90/10 weight ratio) Emulsion (average particle size 0.32 μm) (solid content 30%) 250 parts Carbon black aqueous dispersion (solid content 20%) 75 parts Surfactant (Reodol TW-S120) 1 part Oil (polypropylene glycol # 1000) 10 parts Water 84 parts Methanol 80 parts

Example 10 Example 5 was repeated except that the G component of Example 5 was changed to the following L component, and was applied to the first ink layer of Example 5 so as to have a thickness of 1.5 μm by a hot melt coating method. In the same manner as in the above, a thermal transfer recording medium was obtained. (L component) Carnauba wax 70 parts Ethylene-vinyl acetate copolymer (Smitate KE-10 (Sumitomo Chemical Co., Ltd.)) 10 parts Carbon black (MA-7 (Mitsubishi Carbon Co., Ltd.)) 15 parts Oil (mineral oil) 5 copies

Example 11 A thermal transfer recording medium was obtained in the same manner as in Example 5 except that the following M component was applied to the first ink layer of Example 5 so as to have a thickness of 1.4 μm. (M component) Carnauba wax emulsion (average particle size 0.71 μm) (solid content 30%) 250 parts The same composition as the G component in Example 5 except for the above.

Comparative Example 1 A thermal transfer recording medium was prepared in exactly the same manner as in Example 2 except that the component B was replaced with the component R shown below, and a coating solution was prepared by the following coating solution preparation method. (R component) Carnauba wax 73 parts Candelilla wax 15 parts Polybutadiene rubber (manufactured by Nippon Synthetic Rubber Co .; JSR BR 31) 2 parts Ethylene-vinyl acetate copolymer 10 parts (EVA FLEX 210 manufactured by Du Pont-Mitsui Polychemicals) Toluene 900 parts In addition, the preparation of the coating solution of the R component was carried out by ball mill dispersibility at room temperature for 12 hours after heating and mixing the entire composition.

Comparative Example 2 A thermal transfer recording medium was prepared in exactly the same manner as in Comparative Example 1, except that the R component was replaced by the following S component. (S component) Carnauba wax 55 parts Candelilla wax 20 parts Polybutadiene rubber (manufactured by Nippon Synthetic Rubber Co .; JSR BR 31) 15 parts Styrene-butadiene rubber (Nippon Synthetic Rubber Co., Ltd .: JSR 171) 10 parts Toluene 900 parts

Comparative Example 3 A thermal transfer recording medium was prepared in exactly the same manner as in Comparative Example 1 except that the R component was replaced by the following T component. (T component) Paraffin wax (melting point: 155 ° F.) 75 parts Polybutadiene rubber (Nippon Synthetic Rubber Co .; JSR BR 31) 15 parts Styrene-butadiene rubber (Nippon Synthetic Rubber Co., Ltd .: JSR 1712) 10 parts Toluene 900 parts

Comparative Example 4 The above component A was replaced with the following component U, and after hot melt dispersion,
A thermal transfer recording medium (having a thickness of about 2.6 μm) was prepared in exactly the same manner as in Example 1 except that the coating was performed by the hot melt flexographic printing method. (U component) Carnauba wax 12.0 parts Paraffin wax (melting point: 155 ° F) 60.0 parts Ethylene-vinyl acetate copolymer 12.0 parts (EVA FLEX210 manufactured by DuPont-Mitsui Polychemicals) Carbon black (Mitsubishi Chemical Industry) MA-7) 15.0 parts Mineral oil 1.0 part

COMPARATIVE EXAMPLE 5 Using exactly the same composition and amount as in Example 1, all of these were heated and mixed and then ball milled at room temperature for 12 hours to prepare a coating solution. Using this coating solution, an ink layer was formed in the same manner as in Example 1.

Comparative Example 6 A coating liquid was prepared in the same manner as in Example 1 except that the rubber component (polybutadiene) was omitted, and an ink layer was formed.

Comparative Example 7 During the process of forming the first ink layer in Example 5, drying was performed at 85 ° C.
A thermal transfer recording medium was produced in exactly the same manner as in Example 5, except that the hot air was used. The particles of the first ink layer were fused and became translucent.

[0067]Comparative Example 8  Hot-melt the following X component on the same support as in Example 5.
Apply the coating method to a thickness of 3.0 μm.
Cloth was applied to obtain a thermal transfer recording medium. (Component X) Carnauba wax 40 parts Paraffin wax 32 parts Carbon black 15 parts Mineral oil 3 parts Ethylene-vinyl acetate resin [Summitate KE10 (Sumitomo Chemical Co., Ltd.)] 10 parts

[0068]Comparative Example 9  Example 1 was repeated except that the component A 'in Example 1 was replaced with the following component B'.
A thermal transfer recording medium was produced in exactly the same manner as in Example 1. (B 'component) Candelilla wax (elongation 20%) 26 parts Dispersant 4 parts Water 70 parts

[0069]Comparative Example 10  Example 1 was repeated except that the component A 'in Example 1 was replaced with the following component C'.
A thermal transfer recording medium was produced in exactly the same manner as in Example 1. (C 'component) Beeswax (elongation 30%) 26 parts Dispersant 4 parts Water 70 parts

[0070]Comparative Example 11  Example 1 was repeated except that the component A 'in Example 1 was replaced with the following component D'.
A thermal transfer recording medium was produced in exactly the same manner as in Example 1. (D 'component) Carnauba wax (3% elongation) 18 parts Candelilla wax (20% elongation) 8 parts Dispersant 4 parts Water 70 parts

[0071]Comparative Example 12  Example 1 was repeated except that the component A 'in Example 1 was replaced with the following component E'.
A thermal transfer recording medium was produced in exactly the same manner as in Example 1. (E 'component) Carbana wax (elongation 3%) 18 parts Beeswax (elongation 30%) 8 parts Dispersant 4 parts Water 70 parts 10 types of thermal transfer recording media of Examples 1-4 and Comparative Examples 1-6
Lightweight coated paper with a Beck smoothness of about 400 seconds
(New Age 55 manufactured by Kanzaki Paper Co., Ltd.)
5 using a transfer printer (manufactured by TEC: B-65)
Under the condition of 35 ° C. and 35% RH, the standard energy is
It was given and printed. The results were as shown in Table 1.

[0072]

[Table 1] (Remarks) Transferability: Evaluation was made based on whether or not the bar code portion was clearly printed. …: The bar code portion is clearly printed and transferred. X: Some bar codes are not clearly transferred, and bar codes are not clearly printed. Bar code reading rate: The bar code portion was scanned 100 times with a laser check LC-2811 (manufactured by Symbol Technologies, Inc.) and the number of times the bar code could be read was expressed as a percentage. That is, a reading rate of 100% indicates that scanning was performed 100 times with the laser beam and reading was performed 100 times, indicating that the barcode was clear. Abrasion resistance: The printed barcode image was tested in an atmosphere of 50 ° C. Objective: Corrugated paper Pressure: 80 g / cm ² Number of rubs: 100 times The test was performed. The printed matter subjected to the friction test was evaluated by a barcode reading rate by a barcode reading rate measuring method. Occurrence of dirt: presence or absence of dirt on the receiving paper when the head detaching mechanism is used. As is clear from the above results, all the thermal transfer recording media according to the present invention (Examples 1 to 4) have good transferability, It can be seen that the code can be completely read.

The nine types of thermal transfer recording media of Examples 5 to 11 and Comparative Examples 7 to 8 were coated with recycled paper (paper source (manufactured by Ricoh)) having a Beck smoothness of about 50 seconds and a lightweight coat of about 400 seconds. Lightweight coated paper (Kanzaki Paper, New Age 70)
In addition, a barcode paper thermal transfer printer (manufactured by Atech:
Using SWEDOT 196), printing was performed under the conditions of 20 ° C. and 60% RH while applying standard energy.
The results were as shown in Table 2.

[Table 2]

Transferability: Evaluation was made on whether or not the bar code portion was clearly printed. …: The bar code portion is clearly printed and transferred. X: Some bar codes are not clearly transferred, and bar codes are not clearly printed. Bar code reading rate: The bar code portion was randomly scanned 100 times with a laser check LC-2811 (Symbol Technologies, Inc.), and the number of readings was expressed as a percentage. That is, a reading rate of 100% indicates that the laser was scanned 100 times and reading was performed 100 times, indicating that the barcode was clear. Abrasion resistance (cardboard test): A 4 cm × 7 cm square cardboard plate was placed on a bar code portion, and a load of 1 kgf was applied, and the same place was rubbed 50 times with a love tester to evaluate. ○ ... The bar code part is almost clean and can be read without any problem by a bar code scanner. ×: The barcode area is very dirty and difficult to read with a barcode scanner. Occurrence of dirt: Whether or not the receiving paper is dirty when the head removal mechanism is used

With respect to the five types of thermal transfer recording media of Example 1 and Comparative Examples 9 to 12 , a bar code thermal transfer printer (TEC) was applied to surface-coated mirror-coated paper (manufactured by Kanzaki Paper) having a Beck smoothness of about 4000 seconds. (Manufactured by: B-600) using a head attachment / detachment mechanism and applying standard energy under conditions of 20 ° C. and 60% RH. Table 3 shows the results
It was as follows.

[Table 3] Occurrence of dirt: presence / absence of dirt on the receiving paper when using the head attaching / detaching mechanism Bar code reading rate: The laser is scanned 100 times with a laser check LC-2811 (Symbol Technologies, Inc.) on the bar code portion. The number of readings was expressed as a percentage. That is, a reading rate of 100% indicates that scanning was performed 100 times by scanning the laser 100 times, which indicates that the barcode was clear.

[0076]

Since the thermal transfer recording medium of the present invention has the above-mentioned constitution, the storage stability when not in use, particularly the storage stability at a low temperature, is increased, and the ink layer is not peeled off. The image receptor that occurs when the thermal head of the printer is activated, such as recording paper, is prevented from becoming dirty, and a clear serial code can be printed.The quality performance has been greatly improved as compared with conventional transfer recording media of the same type. is there.

[Brief description of the drawings]

FIGS. 1A and 1B are views showing two examples of a thermal transfer recording medium according to the present invention.

FIG. 2 is a perspective view illustrating the thickness and width of a plate-like rubber elastomer.

FIG. 3 is a perspective view for explaining a layer interval when a rubber elastomer is formed in a layer shape.

FIG. 4 is a diagram schematically illustrating a state in which a layered rubber elastomer is intermittently dispersed in an ink layer.

FIG. 5 is an explanatory view of a Tensilon tensile compression tester.

FIG. 6 is an explanatory diagram of a method for measuring elongation.

[Explanation of symbols]

 Reference Signs List 102 Support 104a, 104b Ink layer 112 Rubber elastomer 114 Colorant 116 Heat-fusible material 120 Overcoat layer

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-293187 (JP, A) JP-A-60-135290 (JP, A) JP-A-1-247194 (JP, A) JP-A-2- 150387 (JP, A) JP-A-2-160586 (JP, A) JP-A-63-288778 (JP, A) JP-A-1-110186 (JP, A) JP-A-3-227286 (JP, A) JP-A-5-69674 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/38-5/40

Claims (3)

(57) [Claims] 1. A thermal transfer recording medium in which a heat-fusible ink layer and an overcoat layer are sequentially provided on a support, wherein the heat-fusible ink layer mainly contains a colorant, a wax and a rubber elastomer, and excludes a rubber elastomer. Pre-composition material
Add the rubber elastomer component to the dispersed liquid and stir
After mixing or mixing and melting components other than water, pour hot water
Add emulsified under stirring, pre-emulsified, emulsified under high pressure, with water
Quenched and adjusted solids controlled wax emulsion
Ink and rubber latex
A coating liquid for forming a layer is prepared, and the coating liquid is applied and dried to form a coating liquid.
And is intended, moreover the rubber elastomer is being allowed to be present in a layer in and intermittently distributed, the overcoat layer which is elongation at 40 ° C. to 60 ° C. consisting of 5% or less of thermally fusible substance Characteristic thermal transfer recording medium. 2. A first heat-fusible ink layer on a support,
Heat provided with a heat-meltable ink layer and an overcoat layer sequentially
In the transfer recording medium, the first ink layer mainly contains wax and a rubber elastomer, and excludes a rubber elastomer.
A rubber elastomer component is added to a liquid in which the composition material is dispersed in advance.
Add and stir and mix, or mix components other than water
After melting, add hot water with stirring to pre-emulsify and emulsify under high pressure
And quenched with water to adjust the adjusted
To mix rubber latex with mix emulsion
A coating liquid for forming an ink layer, and apply and dry the coating liquid.
And it has been formed, yet the rubber elastomer is dispersedly contained in and intermittently layered, also, the second ink layer all SANYO composed mainly of a colorant, a binder resin and a wax, over The coating layer is stretched at 40 ° C to 60 ° C.
Characterized in that it is made of a heat-meltable substance having a melting rate of 5% or less.
That the thermal transfer recording medium. 3. The heat-meltable ink layer is 5 ° C., 35% R
The thermal transfer recording medium according to claim 1, wherein the thermal transfer recording medium has a shear strength of 25 to 45 gf / cm and an adhesive strength of 1.5 to 3.5 gf / cm under the condition of H. 4.