JPH05254262A - Thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To enhance image quality by improving the close adhesiveness and preservability of a hot-melt ink layer and eliminating the contamination of receiving paper and to enhance the friction resistance of a transfer image. CONSTITUTION:In a thermal transfer recording medium, a rubber elastomer 112 is added to a hot-melt ink layer 104a or 106 in a laminar and discontinuous state and an overcoat layer containing a hot-melt substance with an elongation of 5% or less is provided. When the compounding state of rubber in the hot-melt ink layer is set to a specific form, the contamination of receiving paper is prevented and a sharp transfer image can be obtained.

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 to prevent storage stability especially at low temperatures and prevent the image receptor, that is, the receiving paper, from being stained by a thermal head. More specifically, the present invention relates to a thermal transfer recording medium having excellent printing quality, which is suitable for barcodes and prevents peeling of the ink layer when not in use at a low temperature. The present invention relates to a thermal transfer recording medium having a clear bar code).

[0002]

2. Description of the Related Art In recent years, a thermal transfer recording system using a thermal head is noiseless, the apparatus is relatively inexpensive and can be miniaturized, maintenance is easy, and printed images are stable. It has come to be used more often because of its advantages. Typical examples of the thermal transfer recording medium used in such a thermal transfer recording system are (1) a heat-meltable ink layer comprising a colorant and a binder provided directly on a support, and (2) a heat-meltable property. The ink layer is formed by laminating a first ink layer on the support side and a second ink layer, the first ink layer contains wax as a main component, and the second ink layer contains a colorant and a binder as main components. Those provided on the support, and the like.

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

In order to eliminate such inconvenience, the surface of the support is made uneven so that the contact area between the ink layer and the support is increased (JP-A-58-16889). An intermediate adhesive layer made of a cellulosic resin, a polyester resin or the like is provided between them (Japanese Patent Laid-Open No. 59-165).
No. 690, Japanese Patent Laid-Open No. 60-54894, etc.) has been proposed, but it has a drawback that the manufacturing method and process are complicated and the manufacturing cost is increased.

An ink layer (the ink layer of (1) above,
Since the binder of the above (2) first ink layer and second ink layer) is mainly composed of wax having low plasticity, the adhesive strength of the ink layer becomes low, and as a result, serial barcodes can be obtained by a barcode printer or the like. When printing, the phenomenon of dropout (a phenomenon in which the part to which energy is not applied by the thermal head is also transferred) occurs, resulting in unclear printing. Therefore, a situation may occur in which the barcode cannot be read by the barcode scanner.

Further, the abrasion resistance of the bar code image obtained by the conventional thermal transfer recording medium cannot be said to be sufficient.
That is, it is often accepted that when a thermal transfer image is rubbed with, for example, corrugated cardboard, the barcode is disturbed and unreadable. Further, recent line printers have been equipped with a thermal head up / down mechanism in order to increase the printing speed or save the consumption of the thermal transfer recording medium. Along with this, a problem has arisen in that the receiving paper is soiled at the start or end of high-speed printing or when the head is moved up or down.

[0007]

SUMMARY OF THE INVENTION The first object of the present invention is to improve the adhesion of the ink layer, to improve the preservability, especially at low temperature, and to prevent the occurrence of the drop phenomenon, and at the same time, the thermal head. It is intended to provide a thermal transfer recording medium which is suitable for bar code printing, in which the image quality is improved by preventing the receiving paper and the like from being soiled during operation. Another object of the present invention is to provide a thermal transfer recording medium which has excellent abrasion resistance of an image and does not cause stains on a receiving paper.

[0008]

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 contains a colorant, a wax and a rubber elastomer as main components. In addition, the rubber elastomer is present in a layered form and intermittently dispersed, and the overcoat layer is mainly composed of a heat-meltable substance having an elongation of 5% or less at 40 ° C to 60 ° C. I am trying.

The inventors of the present invention have conducted extensive studies and studies in order to achieve the above-mentioned object, and as a result, have made the blending of the rubber elastomer in the heat-meltable ink layer exist in a specific state and have a specific content in the overcoat layer. It has been found that inclusion of materials can do. 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.
3A and 3B are schematic diagrams 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 the ink layer 108 are laminated. In the figure, 112 is a rubber solid, 114 is a colorant, and 116 is a heat-meltable 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 laminated ink layer 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 the recording paper. Since it is provided, better results can be obtained by relying only on wax. On the other hand, the second ink layer 1
As the heat-fusible material 116 of No. 08, not only the binder resin but also the use of a wax together with the binder resin gives good results.

The 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 of the rubber elastomer 112 is not necessarily the same in size and thickness. However, this plate-shaped rubber elastomer (the solid material has a thickness (T) of 0.02 to 0.5 μm and a width (W) of 0.20 to 5.
It is about 5 μm. The rubber elastomer 112 has a structure in which at least two or more plate-shaped rubber elastomers 112 'are laminated so as to sandwich at least a wax. Here, the phrase "at least sandwich the wax" means that, for example, in the ink layer 104a of FIG. 1A, a part of the binder resin or the colorant other than the wax can enter between the plate-shaped rubber elastomers. This is because there is nature. The layer spacing (G) when the plate-shaped rubber elastomer 112 ′ is layered is 0.01 to 0.
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, and these are common to a plurality of plate-shaped rubber elastomers 112 '. It has a form in which it is laminated via the wax layer 116 ′. However, the plate-like rubber elastomer 112 'does not necessarily have to be entirely flat, and may be partially bent or entirely bent. Furthermore, a large number of plate-shaped rubber elastomers 112 'are
It is not necessary that the dimensions of width and height are all equal, but rather they are different.

As will be apparent from Examples described later, a thermal transfer recording medium in which a layered and discontinuous rubber elastomer 112 'is contained and dispersed in an ink layer can provide a good thermal transfer image. As a result of further research to enhance the effect, the present inventors have specified that the adhesive strength is 1.5 to 3.5 gf / cm under the range of 5 ° C. and 10 to 50% RH. It has been confirmed that a higher quality thermal transfer recording medium can be obtained.

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

In the figure, 1 is a thermal transfer recording medium, and 2 is an adhesive tape (Nichiban: Cellotape 18 m).
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 is a reinforcing plate, and in this case, a thick stainless steel plate was used. 4 is a fixture. As the measuring 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: 50mm / min Specimen width: 10mm Test environment temperature: 5 ℃, 35% RH and 20 ℃, 60% RH

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

The thermal transfer recording medium of the present invention is shown in FIG.
A heat-resistant and / or slippery protective layer may be provided on the back surface (the surface of the support which is in contact with the thermal head) of the support 102 in (b). This heat resistance and / or lubricity protective layer is provided if necessary, but by providing this, the heat resistance and / or lubricity of the support 102 can be improved, and it can be used conventionally. The support material which was not present can be used.

The support 102 includes, for example, plastic film having relatively high heat resistance such as polyester, polycarbonate, triacetyl cellulose, nylon and polyimide, as well as glassine paper, condenser paper, metal foil and the like. Is about 2 to 15 μm, preferably 3
It is about 10 μm.

Examples of the material for the heat resistant and / or slippery protective layer include silicone resin, silicone rubber, silicone modified resin, fluororesin, polyimide resin, epoxy resin, phenol resin, melamine resin and nitrocellulose. ..

The ink layer 104a is a heat-fusible layer, and contains a coloring agent, a wax and a rubber elastomer, or a binder resin in addition to them as a main component.

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

Examples of the wax include paraffin wax, microcrystalline wax, oxidized paraffin wax, candelilla wax, carnauba wax, montan wax, ceresin wax, polyethylene wax, oxidized polyethylene wax, castor wax, tallow-hardened oil, lanolin, wood. Examples thereof include 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,
Binder resins 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. A resin may be used.

The rubber elastomer has a shear strength of the ink layer 104a or 104b of 25 to 45 gf / cm at 5 ° C.
It is necessary for the adhesive strength to develop 1.5 to 3.5 gf / cm. Here, as the rubber elastomer, for example, butadiene rubber, styrene-butadiene rubber, nitrile rubber, nitrile-butadiene rubber, styrene-isoprene rubber, isoprene rubber, acrylic rubber, epichlorohydrin rubber, butyl rubber, ethylene-
Examples include synthetic rubber such as propylene rubber and natural rubber.

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

In addition to these, well-known plasticizers such as fatty acid ester, glycol ester, phosphoric acid ester, and epoxidized linseed oil and oils may be added to the ink layer 104a in a small amount (30% or less). Absent.

The ink layer 104a can be formed by applying it in a state of being melted or dispersed in hot melt or a solvent and drying it, and the thickness thereof is 1 to 10 μm, preferably 2 to 6 μm.
μm (FIG. 1 (a)). The thickness of the ink layer 104a is
If the thickness is less than 1 μm, the density is insufficient and printing defects on the paper having relatively low smoothness occur. On the other hand, if the thickness exceeds 10 μm, the adhesive strength is reduced and the ink layer peels off at a low temperature. Further, if the layer thickness of the ink layer 104a is too large, the shear strength increases, which may cause transfer failure.

Next, the ink layer 104b becomes the first ink layer 1
A thermal transfer recording medium (FIG. 1B) of the type configured by stacking 06 and the second ink layer 108 will be described.

As mentioned above, the first ink layer 106 includes the wax as the heat-fusible material 116, and the rubber elastomer (distributed in a layered manner intermittently).
112 is a main component.

As the wax here, paraffin wax having a melting point of 40 to 100 ° C., microcrystalline wax, oxidized paraffin wax, candelilla wax, carnauba wax, montan wax, ceresin wax, polyethylene wax, oxidized polyethylene wax, caster. Wax, beef tallow, lanolin,
Waxy substances such as wax, sorbitan stearate, sorbitan palmitate, stearyl alcohol, polyamide wax, oleylamide, stearylamide, hydroxystearic acid, synthetic ester wax, and synthetic alloy wax can be mentioned. Those having a penetration of 2 or less are preferable, and carnauba wax is desirable. This is advantageous in that the abrasion resistance of the printed image surface is improved by using a wax having a high hardness, and a highly reliable bar code image is maintained. Of 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 makes the first ink layer 106 and the second ink layer 108 together and has a shear strength of 25 to 45 gf / cm at 5 ° C. and an adhesive strength of 1.5 to 3.5 gf / cm. Is preferable for expressing.

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

On the other hand, the shear strength is 45 gf at 5 ° C.
/ Cm and the adhesive strength is more than 3.5 gf / cm, the adhesive force to the support becomes larger than the adhesive force to the transfer paper, resulting in a phenomenon such as transfer failure.

The weight ratio of each material constituting the first ink layer 106 is wax / rubber elastomer = 95 to 75/5.
About 25 is suitable.

As the first ink layer 106, polyvinyl butyral, vinyl chloride-
Vinyl acetate copolymer resin, nitrocellulose, epoxy resin, ethylene-vinyl acetate copolymer resin, ethylene-α-olefin copolymer resin, α-olefin-maleic anhydride copolymer resin, ethylene-methacrylic acid copolymer resin, ethyl cellulose, etc. One kind or two or more kinds of the above resins may be mixed in an appropriate amount.

The thickness of the first ink layer 106 is 0.5 to 10
μm, preferably 1 to 3 μm. Thickness is 0.5 μm
If it is thinner, the function as a peeling layer is lowered and the transferability to paper having a relatively small smoothness is deteriorated. Also, the thickness is 10μ
When it exceeds m, the adhesive strength is lowered and the ink layer peels at a low temperature (5 to 10 ° C.). Further, if the thickness of the peeling layer 106 is too large, the shear strength increases, which may result in transfer failure. Furthermore, the wear resistance of an image can be improved by using a specific wax for hot-melt ink. The second ink layer 108 contains a colorant, a binder and a wax as main components. Second ink layer 108
Has a thickness of 0.5 to 4 μm, preferably 1 to 3. Further, it is appropriate that the weight ratio of the colorant which is the main component of the layer 108 and the binder resin is approximately 5:95 to 20:80.

The 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) makes it possible to obtain a transfer medium that is free from stains in the non-printed portion of the recording paper. According to
It has been found that a material mainly composed of a heat-melting substance having an elongation rate of 5% or less according to a metal material tensile test method (JIS Z2241) described later is particularly suitable for clearly printing a serial code.

<Measurement Method of Elongation Rate> A heat-melting material molded into a dumbbell shape as shown in FIG. 6 is used-this is set as shown in the drawing, and it is stretched in the direction of the arrow and its elongation is Y. .. Tensile speed: 1 mm / min Load converter: wa × 5 Kgf or wa × 200 Kgf Elongation is calculated by the following formula. 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 saturated aliphatic hydrocarbon resin.

The film 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 stains is poor, and if it exceeds 5 μm, transfer of the heat-meltable ink is impaired, which is not preferable.

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, and mapine oil, polyolefins, polyglycols, polyphenyl ethers, dihydrochlorides, neopentylpolyolesters, phosphates, Synthetic lubricating oils such as polychlorofluoroethylene, fluoroesters, silicone compounds, and silicone resins are available. As a surfactant,
Anions such as fatty acid salts, alkyl sulfate salts, alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl sulfosuccinates, alkyl phenyl ether disulfonates, alkyl phosphates, polyoxyethylene alkyl allyl sulfates Surfactants, cationic amines such as alkylamine salts and quaternary ammonium salts, amphoteric surfactants such as alkylhetines and amine oxides, and polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylenes. Derivatives, oxyethylene / oxypropylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters Ether, nonionic surfactants such as polyoxyethylene alkyl amines, etc., there are various things, these fluorine-based, the silicon-based, also include those of acetylenic.

[0043]

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

Example 1 Polyethylene terephthalate (PE having a thickness of about 5.5 μm)
T) A coating solution of the following component A is applied on the film using a wire bar so that the thickness after drying is about 3.5 μm,
An ink layer was formed by drying at 60 ° C. (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 Co., Ltd .: MA-7) 15 parts Toluene 492 parts Methyl isobutyl ketone 180 parts The preparation of the coating liquid of the component A was carried out by heating and kneading the composition excluding the polybutadiene rubber (5% toluene solution) in advance, and then ball milling at room temperature for 12 hours to obtain a dispersion liquid. Then, polybutadiene rubber (5% toluene solution) was added to this dispersion with stirring. Further, a coating liquid consisting of the following A'component has a thickness after drying of about 1 μm.
It was applied so as to have a thickness of m, and dried at 45 ° C. to form an overcoat layer. (A 'component) Carnauba wax (elongation rate 3%) 20 parts Rice wax (elongation rate 5%) 6 parts Dispersant 4 parts Water 70 parts

Example 2 Polyethylene terephthalate (PE having a thickness of about 5.5 μm)
T) A coating liquid of the following component B is applied onto the film using a wire bar so that the thickness after drying is about 1.5 μm,
The first ink layer was formed by drying at 55 ° C. (Component B) Carnauba wax 88 parts Polybutadiene rubber 5% toluene solution 240 parts (Nippon Synthetic Rubber Co., Ltd .: JSR BR 31) Toluene 492 parts Methyl isobutyl ketone 180 parts In addition, the preparation of the component B coating liquid is A component. In the same manner as in Example 1, the composition excluding the rubber component was previously dispersed, and the rubber component was added thereto. Further, a coating liquid containing the following component C was applied thereon by 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 Carbon black aqueous dispersion (solid content 30%) 75 parts Surfactant (Kao Atlas KK Leodol TW-S120) 1 part Water 61 parts Methanol 80 parts Furthermore, a coating liquid consisting of the above-mentioned A ′ component is further applied under the same conditions. Was applied and dried to form an overcoat layer.

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

Example 4 A thermal transfer recording medium was prepared in the same manner as in Example 2 except that the B component was replaced with the E component described below. (E component) Carnauba wax 70 parts Montan wax (Hoechs I-Wax KP manufactured by Hoechst) 17 parts 5% toluene solution of polybutadiene rubber 5 parts (Nihon Gosei Zeon Co., Ltd .: Higool BBR 1220) 5% of acrylonitrile-butadiene rubber Toluene solution) 100 parts (Nippon Synthetic Rubber Co., Ltd .: JSR N234L) 5% toluene solution of polystyrene resin 60 parts (Esso Standard Petroleum Co., Ltd .: D125) Toluene 568 parts Methyl isobutyl ketone 180 parts

Example 5 Polyethylene terephthalate (PE having a thickness of about 4.5 μm)
T) A coating liquid of the following F component is applied onto the 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 warm air at 60 ° C.

(F component) Carnauba wax emulsion below (solid content 30%) 1) (Average particle size 1.04 μm) 150 parts Butadiene rubber latex (solid content 50%) (JSR # 0700, manufactured by Japan Synthetic Rubber Co., Ltd.) 10 parts water 90 parts Further, a coating liquid comprising the following G component was applied thereon with 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.

(Component G) Carnauba wax emulsion 2) (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 components other than water were mixed and melted at 90 ° C., the remaining hot water was added with stirring and pre-emulsified with a disperser. Then, the mixture was emulsified with a high pressure homogenizer and quenched with water. The average particle size was 1.25 μm.

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

Example 6 A thermal transfer recording medium was prepared in exactly the same manner as in Example 5, except that the F component in Example 5 was replaced with the H component described below. (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 Japan Synthetic Rubber Co., Ltd.) 88 parts of water

Example 7 A thermal transfer recording medium was prepared in the same manner as in Example 5 except that the F component in the above Example 5 was replaced with the following I component. (Component I) Carnauba Wax: Lanolin Derivative Synthetic Wax Emulsion of mixed wax 9: 1 (solid content 30%) (average particle size 2.10 μm) 155 parts Carboxy-modified acrylonitrile butadiene latex (solid content 50%) (JSR0910) Made by Japan 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 co-weight 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 the 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 on the first ink layer of Example 5 by a hot melt coating method so as to have a thickness of 1.5 μm. A thermal transfer recording medium was obtained in the same manner as. (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.)} 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 coated on 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 of Example 5 except for the above.

Example 12 Polyethylene terephthalate (PE having a thickness of 4.5 μm)
T) A coating liquid of the following N component is applied on the film using a wire bar so that the thickness after drying is about 1.8 μm,
The first ink layer was formed by drying with warm air at 60 ° C. First
The porosity calculated from the ink layer thickness and the weight was 18.4%. (N component) Carnauba wax water dispersion (solid content 30%) (average particle size 1.2 μm) 150 parts Butadiene rubber water dispersion (solid content 50%) 10 parts Water 90 parts Furthermore, the following O component After the coating liquid was dried, the coating liquid was applied with a wire bar to a thickness of about 1.2 μm and dried to form a second ink layer. (O component) 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 Carbon black aqueous dispersion (solid content 20%) 75 parts Surfactant (Reodol TW-S120) 1 part Water 61 parts Methanol 80 parts Furthermore, a coating liquid comprising the above-mentioned component A'is applied and dried under the same conditions. To form an overcoat layer.

Example 13 A thermal transfer recording medium was prepared in the same manner as in Example 12 except that the N component was replaced with the P component described below. The porosity was 12.0%. (P component) Carnauba wax: candelilla wax = 7: 3, mixed wax aqueous dispersion (solid content 30%) (average particle size 0.9 μm) 155 parts Styrene-butadiene rubber aqueous dispersion (solid content 50% ) 7 parts water 88 parts

Example 14 A thermal transfer recording medium was prepared in the same manner as in Example 12 except that the N component was replaced with the following Q component. The porosity was 15.5%. (Component Q) Carnauba wax: Lanolin derivative synthetic wax = 9: 1, mixed wax aqueous dispersion (solid content 30%) (average particle size 1.5 μm) 155 parts Carboxy-modified acrylonitrile-butadiene aqueous dispersion (solid content 50) %) 10 parts Water 85 parts

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 by the component R described below and the coating liquid was prepared by the coating liquid preparation method described below. (R component) Carnauba wax 73 parts Candelilla wax 15 parts Polybutadiene rubber (Nippon Synthetic Rubber Co., Ltd .; JSR BR 31) 2 parts Ethylene-vinyl acetate copolymer 10 parts (Mitsui DuPont Polychemical EVA EVA FLEX 210) Toluene 900 parts The preparation of the coating liquid of the R component was carried out by heating and melting the entire composition described above and then performing ball mill dispersibility at room temperature for 12 hours.

Comparative Example 2 A thermal transfer recording medium was prepared in the same manner as in Comparative Example 1 except that the R component was changed to the S component described below. (S component) Carnauba wax 55 parts Candelilla wax 20 parts Polybutadiene rubber (Nippon Synthetic Rubber Co., Ltd .; 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 Comparative Example 1 except that the R component was replaced with the T component described below. (T component) Paraffin wax (melting point 155 ° F) 75 parts Polybutadiene rubber (manufactured by Japan Synthetic Rubber Co., Ltd .; JSR BR 31) 15 parts Styrene-butadiene rubber (manufactured by Japan Synthetic Rubber Co., Ltd .: JSR 1712) 10 parts Toluene 900 parts

Comparative Example 4 The hot melt dispersion was carried out by substituting the following U component for the B component,
A thermal transfer recording medium (thickness was about 2.6 μm) was prepared in exactly the same manner as in Example 1 except that coating was carried out 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 (Mitsui DuPont Polychemical EVA EVA FLEX210) Carbon black (Mitsubishi Kasei Kogyo) MA-7) 15.0 parts Mineral oil 1.0 parts

Comparative Example 5 A coating solution was prepared by using the same composition and amount as in Example 1 and heating and melting all of them, followed by ball milling for 12 hours at room temperature. Using this coating liquid, 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 removed to form an ink layer.

Comparative Example 7 Drying was performed at 85 ° C. in the process of forming the first ink layer of Example 5.
A thermal transfer recording medium was prepared in exactly the same manner as in Example 5 except that hot air was used. The first ink layer became translucent due to the fusion of the particles.

Comparative Example 8 A thermal transfer recording medium was prepared in exactly the same manner as in Example 5, except that the F component in Example 5 was replaced with the V component described below. (Component V) Carnauba wax emulsion (solid content%) (average particle size 4.6 μm) 150 parts Butadiene rubber latex (same as in Example 1) (solid content 50%) 10 parts Water 90 parts

Comparative Example 9 A thermal transfer recording medium was prepared in exactly the same manner as in Example 5, except that the F component in Example 5 was replaced with the W component described below. (W component) Paraffin wax (mp 70 ° C.) (solid content 30%) (average particle size 0.8 μm) 155 parts Styrene-butadiene rubber aqueous dispersion (solid content 50%) (same as Example 2) 7 parts water 88 parts

Comparative Example 10 The following component X was coated on the same support as in Example 5 by the hot melt coating method to a thickness of 3.0 μm to obtain a thermal transfer recording medium. (X component) Carnauba wax 40 parts Paraffin wax 32 parts Carbon black 15 parts Mineral oil 3 parts Ethylene-vinyl acetate resin [Smitate KE10 (Sumitomo Chemical Co.)] 10 parts

Comparative Example 11 A thermal transfer recording medium was prepared under the same conditions as in Example 5 except that the portion of the first ink layer having a particle size of 0.6 to 3.0 μm of the carnauba wax emulsion was 53.4%. ..

Comparative Example 12 In the process of forming the first ink layer of Example 12, drying was performed to 85
A thermal transfer recording medium was prepared in exactly the same manner as in Example 12 except that hot air at ℃ was used. The porosity was 0%.

Comparative Example 13 A thermal transfer recording medium was prepared in the same manner as in Example 12 except that the N component was replaced with the Y component described below. The porosity was 32.0%. (Y component) Carnauba wax water dispersion (solid content 30%) (average particle size 3.5 μm) 150 parts Butadiene rubber water dispersion (solid content 50%) 10 parts Water 90 parts

Comparative Example 14 A thermal transfer recording medium was prepared in the same manner as in Example 12 except that the N component was replaced with the Z component described below. The porosity was 11.0%. (Z component) Paraffin wax (mp 70 ° C.) (solid content 30%) (average particle size 0.8 μm) 155 parts Styrene-butadiene rubber aqueous dispersion (solid content 50%) 7 parts Water 88 parts

Comparative Example 15 A thermal transfer recording medium was prepared in the same manner as in Example 1 except that the component A ′ in Example 1 was replaced with the component B ′ described below. (B'component) Candelilla wax (elongation 20%) 26 parts Dispersant 4 parts Water 70 parts

Comparative Example 16 A thermal transfer recording medium was prepared in exactly the same manner as in Example 1, except that the A ′ component in Example 1 was replaced with the C ′ component described below. (C 'component) Beeswax (Elongation rate 30%) 26 parts Dispersant 4 parts Water 70 parts

Comparative Example 17 A thermal transfer recording medium was prepared in exactly the same manner as in Example 1 except that the component A ′ in Example 1 was replaced with the following component D ′. (D'component) Carnauba wax (elongation rate 3%) 18 parts Candelilla wax (elongation rate 20%) 8 parts Dispersant 4 parts Water 70 parts

Comparative Example 18 A thermal transfer recording medium was prepared in exactly the same manner as in Example 1 except that the A ′ component of Example 1 was replaced with the following E ′ component. (Component E ′) Carnauba wax (elongation rate 3%) 18 parts Beeswax (elongation rate 30%) 8 parts Dispersant 4 parts Water 70 parts Ten types of thermal transfer recording media of Examples 1 to 4 and Comparative Examples 1 to 6 For a light-weight coated paper (New Age 55, manufactured by Kanzaki Paper Co., Ltd.) having a Beck smoothness of about 400 seconds, a thermal transfer printer for barcodes (manufactured by TEC: B-65) was used.
Printing was performed by applying standard energy under the conditions of ° C and 35% RH. The results are shown in Table 1.

[0081]

[Table 1] (Remarks) Transferability: It was evaluated by whether or not the bar code part was clearly printed. ○: The bar code part is clearly printed and transferred. X: The bar code portion is unclearly printed, and some bar codes are not partially transferred. Bar code read rate: Laser check on the bar code part LC-2811 (Symbol Technology)
ies, Inc. (Manufactured by the company), the laser was scanned 100 times, and the number of times the laser could be read was expressed as a percentage. That is, the reading rate of 100% means that the laser could be scanned 100 times to read 100 times, and the bar code was clear. Abrasion resistance: The printed bar code image was tested under an atmosphere of 50 ° C. under the conditions of: objective: corrugated cardboard pressure: 80 g / cm ² number of rubs: 100 times. The printed matter subjected to the friction test was evaluated by the bar code reading rate by the bar code reading rate measuring method. Occurrence of Contamination: Presence or Absence of Contamination on Receiving Paper When Using Head Detachment Mechanism As is clear from the above results, all of the thermal transfer recording media (Examples 1 to 4) according to the present invention have good transferability, It turns out that the reading of the code is perfectly possible.

The 12 types of thermal transfer recording media of Examples 5 to 11 and Comparative Examples 7 to 11 were coated with recycled paper [Paper Source (manufactured by Ricoh Co.)] having a Beck smoothness of about 50 seconds and a light weight of about 400 seconds. Lightweight coated paper (Kanzaki Paper, New Age 7
0) using a bar code paper thermal transfer printer (Atech: SWEDOT196) at 20 ° C. 60% RH
Under the conditions of, printing was performed by applying standard energy. The results are shown in Table 2.

[Table 2]

Transferability: Evaluation was made based on whether or not the bar code portion was clearly printed. ○: The bar code part is clearly printed and transferred. X: The bar code portion is unclearly printed, and some bar codes are not partially transferred. Bar code read rate: Laser check on the bar code part LC-2811 (Symbol Technology)
ies, Inc. (Manufactured by the company), the laser was randomly scanned 100 times, and the number of times the laser could be read was expressed as a percentage. That is, a reading rate of 100% is 100
It shows that the laser could be scanned 100 times to read 100 times, and the bar code was clear. Abrasion resistance (cardboard test): 4c on bar code
A cardboard plate of m × 7 cm square was applied, and while applying a load of 1 kgf, the same place was slung 50 times with a love tester and evaluated. ○: The barcode part is almost clean and can be read with a barcode scanner without any problems. ×: The bar code part is very dirty and difficult to read with a bar code scanner. Occurrence of dirt: Presence of dirt on the receiving paper when using the head detachment mechanism

6 of Examples 12-14 and Comparative Examples 12-14
For thermal transfer recording media of various types, high-quality paper (made by FSK) having a Beck smoothness of about 70 seconds and surface-treated mirror-coated paper (made by Kanzaki Paper) of about 4000 seconds were used for a bar code paper thermal transfer printer (made by Atech). : SWEDOT196)
Printing was carried out by applying standard energy under the conditions of 20 ° C. and 60% RH. The results are shown in Table 3. The evaluation was as follows. Transferability: It was evaluated by whether or not the bar code part was clearly printed. ○: The bar code part is clearly printed and transferred. X: The bar code portion is unclearly printed, and some bar codes are not partially transferred. Bar code read rate: Laser check on the bar code part LC-2811 (Symbol Technology)
ies, Inc. (Manufactured by the company), the laser was randomly scanned 100 times, and the number of times the laser could be read was expressed as a percentage. That is, a reading rate of 100% is 100
It shows that the laser could be scanned 100 times to read 100 times, and the bar code was clear. Abrasion resistance (cardboard test): 4c on bar code
A cardboard plate of m × 7 cm square was applied, and while applying a load of 1 kgf, the same place was slung 50 times with a love tester and evaluated. ○: The barcode part is almost clean and can be read with a barcode scanner without any problems. ×: The bar code part is very dirty and difficult to read with a bar code scanner. Occurrence of dirt: Presence of dirt on the receiving paper when using the head detachment mechanism

[Table 3] Regarding the five types of thermal transfer recording media of Example 1 and Comparative Examples 15 to 18, surface-treated mirror-coated paper (made by Kanzaki Paper Co., Ltd.) having a Beck smoothness of about 4000 seconds was applied to a bar code thermal transfer printer (made by TEC: B-600) was printed by using a head attachment / detachment mechanism under standard conditions of 20 ° C. and 60% RH by applying standard energy. The results are shown in Table 4.

[Table 4] Occurrence of dirt: Presence of dirt on the receiving paper when using the head detachment mechanism Bar code reading rate: Laser check of bar code LC-2811 (Symbol Technology)
ies, Inc. (Manufactured by the company), the laser was scanned 100 times, and the number of times the laser could be read was expressed as a percentage. That is, the reading rate of 100% means that the laser could be scanned 100 times to read 100 times, and the bar code was clear.

[0085]

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 low temperature is increased and the ink layer is not peeled off. It is possible to prevent stains on the image receptor such as recording paper that occurs when the thermal head of the printer is activated, and it is possible to print clear serial codes, and the quality performance has been significantly improved compared to the conventional transfer recording medium of the same type. is there.

[Brief description of drawings]

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

FIG. 2 is a perspective view for explaining the thickness and width of a plate-shaped rubber elastomer.

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

FIG. 4 is a diagram schematically showing how a layered rubber elastomer is intermittently dispersed in an ink layer.

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

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

[Explanation of symbols]

 102 Supports 104a, 104b Ink Layer 112 Rubber Elastomer 114 Colorant 116 Thermal Melting Material 120 Overcoat Layer

Claims (4)

[Claims] 1. A thermal transfer recording medium in which a heat-meltable ink layer and an overcoat layer are sequentially provided on a support, wherein the heat-meltable ink layer contains a colorant, a wax, and a rubber elastomer as main components, and further, the rubber elastomer. Is present in the form of a layer and is intermittently dispersed, and the overcoat layer is mainly composed of a heat-meltable substance having an elongation of 5% or less at 40 ° C to 60 ° C. .. 2. The first heat-fusible ink layer is on the support side.
The ink layer and the second ink layer formed on the first ink layer are laminated, and the first ink layer contains wax and a rubber elastomer as main components, and the rubber elastomer is dispersed in layers and intermittently. The thermal transfer recording medium according to claim 1, wherein the second ink layer contains a colorant, a binder resin, and a wax as main components. 3. The thermal transfer recording medium according to claim 1, wherein a slip protective layer is provided on the surface of the support opposite to the surface on which the heat fusible ink layer is provided. 4. The heat-meltable ink layer is 5 ° C. and 35% R
The thermal transfer recording medium according to claim 1, which 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.