JPS6137472A - Thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To obtain a highly fixable and high-resolution pixel-transferred image which can be printed at low energy and well under fog control by specifying resin components and heat-meltable material contents. CONSTITUTION:The surface of a support has a heat-meltable coloring material layer containing a color developer, heat-meltable material, resin A having a softening or melting point of 50-130 deg.C, glass transition point of 45 deg.C or more, breaking ductility of 10% or less and melting viscosity at 150 deg.C of 1X10<2>- 1X10<5> and resin B having a softening or melting point of 80 deg.C or more, glass transition point of 20 deg.C or less and breaking ductility of 50% or more. This heat-meltable coloring material layer should contain 15-95wt% of the afore- mentioned heat-meltable material, 0.5wt% min. - not more than 10wt% of resin A and 0.1wt% min. - not more than 5wt% of resin B. The composition surface of said thermal transfer recording medium and an ordinary-type recording sheet are overlapped so that a comparatively lower energy may be applied to the heat-meltable color-forming material layer. Thus the color developer, etc. are transferred to a recording sheet with heat-meltable material.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a thermal transfer recording medium, and more specifically, the present invention relates to a thermal transfer recording medium that can be printed with low energy and that prevents background smudges (capri) from occurring on recording sheets such as plain paper. The present invention relates to a heat-sensitive transfer recording medium that can suppress the oxidation, have excellent fixing properties to a recording sheet, and provide a high-resolution Q dye transfer image.

[Prior Art] A thermal transfer recording medium has been conventionally used as a recording body for transferring and forming an image on a recording sheet such as plain paper by a thermal printer, a thermal facsimile, or the like. This thermal transfer recording medium has at least one coloring material layer on a support, and the coloring material layer may include, for example, a layer containing a coloring agent such as a pigment and a heat-melting coloring material layer. Are known.

When using a thermal printer or thermal facsimile with a thermal head to record a dye transfer image on plain paper or the like using such a thermal transfer recording medium,
Although it is desired to print with low energy, conventional thermal transfer recording media have been insufficient due to low transfer sensitivity. Furthermore, there was also the drawback that background stains (fogging) occurred on the recording sheet.

For example, JP-A-57-105395 states that the softening point or melting point is 50 to 130°C, the glass transition point is 45°C or higher, the elongation at break is 10% or less, and the melt viscosity at 150°C is lXl0"-lXl0 cp. A resin (A) that is
Softening point or melting point is 80℃ or higher, glass transition point is 20℃
Hereinafter, a coloring material layer mainly containing a resin (B) having a breaking elongation of 50% or more and a coloring agent is disclosed. A thermal transfer recording medium having such a coloring material layer could not be printed at low energy.On the other hand, one way to improve printing performance at low energy is to improve the thermal conductivity of the coloring material layer. The technology was published in 1983.
It is disclosed in Japanese Patent No. 75894. The invention is a technology for containing a powdered thermally conductive substance in a coloring material layer, and since it requires the use of additives, the coloring material layer may become thick depending on the type of additive, resulting in poor resolution. There were cases where it decreased. Furthermore, there was also the drawback that background stains (fogging) occurred on recording sheets such as plain paper.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned circumstances. The technical problem is to be able to suppress the occurrence of dye transfer, have excellent fixing properties to a recording sheet, and obtain a high-resolution dye transfer image.

[Means for Solving the Problems] The heat-sensitive transfer recording medium of the present invention for solving the above-mentioned technical problems includes: (1) a coloring agent, (2) a heat-melting substance, (2) a softening point or a melting point of 50. ~130℃, glass transition point is 45
℃ or higher1. Breaking elongation is 10% or less.

The resin (A) has a melt viscosity of 1×10 to 1×10CP at 150° C., and a softening point or melting point of 80° C. or higher.

A thermal transfer recording medium having a heat-melting coloring material layer containing a resin component containing a resin (B) having a glass transition point of 20° C. or less and a breaking elongation of 50% or more, the heat-melting coloring material layer The content of the heat-melting substance is 15 to 95% by weight, the content of the resin (A) is 0.5% by weight or more and less than 10% by weight, and the content of the resin (B) is 15% to 95% by weight. It is characterized by being 0.1% by weight or more and less than 5% by weight.

That is, in order to solve the above technical problem, the present inventors did not use the conventional method of adding a thermally conductive substance, but instead used a specific resin component and a heat-melting substance.

By specifying the content of , the technical problem of the present invention was successfully solved. By using two specific types of wax in combination, they succeeded in obtaining even better effects.

The present invention will be explained in more detail below.

The heat-sensitive transfer recording medium of the present invention has at least one heat-melting coloring material layer on a support. .

The heat-melting coloring material layer in the heat-sensitive transfer recording medium of the present invention is
A colorant-containing layer that is partially or entirely transferred to an image-receiving sheet (image-receiving element) such as plain paper by heat, and contains at least the components (1), (2), and (2) above. The heat-melting substance to be used has a melting point (value measured by purlin MPJ-2 type) or a softening point (value measured by ring and ball method) of 40 to 120°C, preferably 60 to 1.
A solid or semi-solid substance at 20°C, especially in combination with hard wax and soft wax (one type each or 2M1 or more)
Examples of preferable hard waxes (waxes with a penetration degree (according to JIS K 2530) of less than 8 at 25°Q (100 g)) include: ■ Ester waxes (natural ester waxes such as carnauba wax and montan wax); and Haechst Wax E manufactured by Hoechst,
F, KP, KPS, BJ, OP, OM, X22.1
1 and 0 synthetic ester wax, etc.), ■ Oxidized wax (wax obtained by oxidizing wax such as paraffin wax and microcrystalline wax, -NPS-9210.NFS-8115 manufactured by Hiki Seiro Co., Ltd., Toyo Petro PETR0NABA・C, C; ARD manufactured by Wright Co., Ltd.
IS 314 etc.), ■Low molecular weight polyethylene wax (
In particular, waxes with a molecular weight of 300 to 1000, such as POLYWAX 500 and 955 manufactured by Toyo Petrolite Co., Ltd.), ■ Acid wax (J Hoechst Wax manufactured by Toyo Petrolite Co., Ltd.),
(S and LP, etc.), (2) synthetic waxes, or Diakaruna 30 and Diakaruna PA30L (manufactured by Mitsubishi Kasei Corporation). In addition, soft wax [25℃ (
Examples of waxes with a penetration rate (according to JIS K 2530) of 8 or higher in 100g) include microcrystalline wax (Shiraishi Microwax 155,
180 (manufactured by Nippon Oil Co., Ltd.), former MIC knee 1080.
Old-MIC-2095, HI-MIC-20135.

Hl-MIG-1070, HI-Ml (nee 1045.
Hl-MIG-2045 (manufactured by 8Kiseiri Co., Ltd.), 5TA
RWAX 100. BE 5QUARE 175,19
5゜V ICTORY, ULTRAFLEX (Toyo Petrolite Co., Ltd. tA), etc.), stearic acid, behenic acid, stearyl alcohol, white wax, beeswax, dodecyl stearate, stearon, sorbitan monostearate, polyoxyethylene monostearate, Examples include paraffin wax (such as Paraffin Wax 155 manufactured by Hiki Seiro Co., Ltd.). Note that when such hard wax and soft wax are used in combination, the weight ratio used is 1:9 to 8:1 (more preferably 2:8 to 8:1).
8:2) is fine.

Examples of the resin (A) used in the present invention include low molecular weight styrene resins, petroleum resins, rosins, hydrogenated rosins, terpene resins, xylene resins, styrene-olefin copolymers, aromatic hydrocarbon resins, etc. be able to.

Examples of the resin (B) used in the present invention include ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, styrene-butadiene copolymer, natural rubber, styrene-ethylene-butylene copolymer, chlorinated - Vinyl-vinyl acetate copolymer, etc. can be mentioned.

Resin (A) and resin (B) of the present invention may be used alone, or each or one of them may be used in combination of two or more types, and furthermore, they may be used in combination with other resins. .

The coloring agent contained in the 7 layers of the heat-melting coloring material of the present invention may be appropriately selected from among dyes and pigments, and examples of the dye include basic dyes and oil-soluble dyes (including oil-soluble metal complex dyes). , resistant dyes, direct dyes, disperse dyes, etc. These dyes may also be ballasted dyes, while the pigments may be organic pigments such as phthalocyanine pigments or carbon black. Inorganic pigments and the like can be used.

The basic dye preferably used as the coloring agent of the present invention is, for example, crystal violet (C, 1°4255
5), malachite green (C, 1,42000),
methyl violet) (C:, 1.42535),
Triphenylmethane dyes such as Victoria Blue (C, 1, 44045), Mazienta (C, 1, 42510), diphenylmethane dyes such as Auramine (C:, 1°655), Astraphloxin FF (C:, 1 .4
8070), Eisenkatyron Yellow 3GLH (Hodogaya Chemical Co., Ltd. product, C, 1,48055), Eisenkyiron Red 8BH (C, 1,48020), Astrazone Golden Yellow GL (Bayer Co., Ltd. product, C,
1,48054), xanthine dyes such as Rhodamine B (C:, 1.45170), Rhodamine 6G (C:, 1.45180), Astrasomble-GL (C, 1,11052)
, Astrazone Red F3BL (C, 1, 11055
) and other thiazole azo and triazole azo dyes,
Eisencatylone Blue-50) I (C, 1,110
95), quinoneimine dyes such as methylene blue (C, 1, 52015), Eisen Chiron Red GTL
) 1 (C, 1, 11095), Cevron Yellow 3R
Examples include insulating azo dyes and anthraquinone dyes having an onium group at the structural end, such as L (manufactured by DuPont, C:, 1.110B?) and Astrazone Blue FGL (C, 1, 81512).

The oil-soluble metal complex dyes are, for example, symmetrical l:2 type azo metal complex dyes, asymmetrical 1:2 type azo metal complex dyes, 1
: Type 1 azo metal complex dyes, azomethine metal complex dyes, formazan metal 31N salt dyes, gold u-y talocyanine dyes, and organic base salts of these dyes. Specifically, a.

Izenspiron Yellow 3RH (Hodogaya Chemical Company product, C
, 1, Solvent Yellow = 25), Zapon Fast Yellow R (BASF product, G, 1.18690)
, Eisenspiron Orange 2RH (C:, 1. Solvent Orange 40).

Pomelo Fast Scarlet B (C, 1, 12783)
, Eisenspiron Red GE) l (C:, 1. Solvent Red 84), Zapon Fast Red BE (C, 1.
, 12715), Zapon Fast Violet BE (
111:, 1.121118), Cyanine Blue〇B
(Sumitomo Chemical Co., Ltd. product, C, 1,74180), Varifast Black +13804 (Orient Chemical Co., Ltd. product, C,
1,12195), Eisensviron Yellow 3RH Special (G, 1. Solvent Yellow 25:1),
Eisenspiron Orange 2RH Special (C, 1,
Solvent Orange 40:l), Eisensviron Blue-28NH (C,I, Solvent Blue 117),
Zapon Fast Blue HFL (C, 1,?435G),
Examples include Eisens Viron Black BH Special (C, 1, Solvent Black 22:1).

Acidic dyes include, for example, C,1, Acid Yellow 19
, C,1, Acid Red 37, C,1, Acid Blue 62, C0! , Acid Orange 10, C,1, Acid Blue 83, C81, Acid Black 01, and the like.

Direct dyes include G, 1. Direct yellow 44, C, I
.

Direct Yellow 142, C, 1, Direct Yellow 12, C, 1, Direct Blue 15, C, R, Direct Blue-25, C, 1, Direct Blue 249
, C,1, Direct Red 8t, C,1, Direct Red 9, C,1, Direct Red 31, C,1,
Examples include Direct Black 154, C,1, Direct Black 17, and the like.

The disperse dyes are G, 1. Disbors Yellow 5, C, 1
, Disbo's Yellow 51. C, I-Disbose Yellow 84. C, 1, Disbo's Red 43, C
, 1, Disbo's Red 54, C, 1, Disbo's Red 135, C, 1, Disbo's Blue 56, C
, 1, Disbo's Bluef 3, C,1, Disbo's 91, and the like.

The ballasted dyes used in the present invention are dyes having at least one ballast group in the dye matrix, such as azo dyes, azomethine dyes, anthraquinone dyes, naphthoquinone dyes, sterine dyes, quinophthalo dyes, and phthalocyanine dyes. Ballast groups are groups with high solubility in heat-fusible substances, such as alkyl groups, cycloalkyl groups, aralkyl groups, alkoxy groups, alkylsulfonylamine groups,
These include groups having an alkyl group or an alkylene group having 6 or more carbon atoms, such as an alkylsulfonyl group, a hydroxylalkyl group, a cyanoalkyl group, and an alkoxycarbonylalkylo group. In particular, a ballast group having at least one alkyl group having 6 or more carbon atoms in the molecule is preferred. Examples of the structure of the ballasted dye preferably used in the present invention include those described in Japanese Patent Application No. 81688/1988 filed by the present applicant, but the present invention is not limited thereto.

Although the composition ratio of the heat-melting coloring material layer of the present invention is not limited,
The amount of the heat-melting substance is 15 to 95% by weight (more preferably 20 to 9% by weight) based on 100% by weight of the total solid content of the heat-melting coloring material layer.
0ffi amount%), colorant is 5 to 30% by weight, resin (A)
The content of the resin (B) is 0.5% by weight or more and less than 10% by weight (more preferably 1% by weight or more and less than 8!l!%), and the content of the resin (B) is 0.1% by weight or more and less than 5% by weight. % (more preferably O-5 layer mmr% or more and less than 5% by weight).

The heat-melting color material layer of the present invention may contain various additives in addition to the above-mentioned components. For example, vegetable oils such as castor oil, linseed oil, olive oil, animal oils such as whale oil, and mineral oils may be suitably used.

The support used in the thermal transfer recording medium of the present invention preferably has heat-resistant strength, high dimensional stability, and high surface smoothness. Materials include, for example, papers such as plain paper, condenser paper, laminated paper, coated paper, resin films such as polyethylene, polyethylene terephthalate, polyethylene, polypropylene, polyimide, paper-resin film composites, aluminum foil, etc. Metal sheets and the like are preferably used. The thickness of the support is usually about 60 pm or less, especially about 1.5 pm in order to obtain good thermal conductivity.
Preferably, the range is between 15 m and 15 m. Furthermore, in the thermal transfer recording medium of the present invention, the structure on the back side of the support may be optional, and a backing layer such as an anti-sticking layer may be provided.

In the heat-sensitive transfer recording medium of the present invention, techniques suitable for applying a constituent layer containing at least one heat-melting coloring material layer to a support such as a polymer film are known in the art, and these techniques are known in the art. Known techniques can also be applied to the present invention.6 For example, a structure including a heat-melting coloring material layer can be formed by hot-melt coating the composition, or by dissolving or dispersing the composition in an appropriate solvent. Coating methods for the constituent layer including the heat-melting coloring material layer of the present invention, which is a layer formed by solvent coating a liquid, include a reverse roll coater method, an extrusion coater method, a gravure coater method, a wire bar coating method, etc. , any technique can be adopted. The heat-melting coloring material layer of the present invention has a volume of 2 liters or less, more preferably 1 liter or less.
It is sufficient if it is set to ~84m.

The thermal transfer recording medium of the present invention may have other constituent layers such as an undercoat layer (for example, a layer for improving film adhesion), an intermediate layer, and an overcoat layer.

A method for thermal transfer recording using the thermal transfer recording medium of the present invention will be described below.

The component layer surface of the thermal transfer recording medium of the present invention and a recording sheet such as plain paper are overlapped, and depending on the image information, the thermal temperature Q using a thermal head, thermal pen, or laser is applied from the thermal transfer recording medium side by a device. Alternatively, when energy is applied from the recording sheet side, relatively low energy is applied to the heat-fusible coloring material layer, so that the colorant and the like are transferred to the recording sheet together with the heat-fusible substance.

[Effects of the Invention] According to the present invention, on the support, (1) a coloring agent, (2) a heat-melting substance, (2) a softening point or melting point of 50 to 130°C, a glass transition point of 45°C or higher, and a breaking elongation of 10 % or less, the resin (A) has a melt viscosity at 150°C of IX 10'-IX 10'cp, a softening point or melting point of 80°C or more, a glass transition point of 20°C or less, and a breaking elongation of 50% or more. In a heat-sensitive transfer recording medium having a heat-fusible colorant layer containing a resin component containing a certain resin (B), the content of the heat-fusible substance in the heat-fusible colorant layer is 15 to 95% by weight. ,
b, - Content of the listed resin (A) is 0.5% by weight or more1
less than 0% by weight, and the content of the resin (B) is 0
．． Since it is 1% by weight or more and less than 5% by weight, it is possible to solve the technical problem of the present invention in which heat is applied.
It improves the ease of thermal transfer (easiness of thermal transfer), enables low-energy printing, and strengthens the film strength (resistance to rubbing and cracking) of the coloring layer of thermal transfer recording media. Furthermore, (1) the adhesion between the support and the coloring material layer can be improved without impairing the ease of thermal transfer.

[Example] Examples are given below, but the embodiments of the present invention are not limited to these. Note that "part" used below refers to "part".
Parts by weight.

Example 1 The following colorant layer compositions (a), (b), (c) and (d) were coated on a 6htn thick polyethylene terephthalate film support to a dry film thickness of 3.5 pm. Thermal transfer recording medium sample (A) of the present invention, (
B).

(C) and (B) were obtained.

Colorant layer composition (a) (melting point 74°C) 45 parts microcrystalline wax (ULTRA, FLEX
.

Toyo Petrolite Co., Ltd.) (melting point 65°C) 30 parts (softening point 80°C) 4 parts Petroleum resin (Alcon P-100° manufactured by Arayo Kagaku Co., Ltd.) 6 parts carbon black 15 parts Coloring layer composition (b) Carnauba Wax (melting point 82°C) 37 parts Microcrystalline wax (Microwax 1551 manufactured by Nippon Oil Co., Ltd.) (melting point 65
℃) 20 parts Paraffin wax (Paraffin wax 155, manufactured by Nippon Seiro Co., Ltd.) (melting point sa ℃) 17 parts Ethylene-vinyl acetate iron lid combination (NUG-3180, manufactured by Nippon Unicar Co., Ltd.) 4
Part aromatic hydrocarbon resin (Vetrozin + 1120° manufactured by Mitsui Petrochemicals) 7 parts Carbon black 15 parts Coloring material layer composition (C) Oxidized wax (NPS-9210, manufactured by Hiki Seiro Co., Ltd.) (melting point 78°C) 45 parts paraffin wax (Paraffin Wax 155 manufactured by Nikki Seiro Co., Ltd.) (melting point 88°C) 30 parts styrene-butadiene copolymer (Toughbrane A, Asahi Kasei 'A') 3 parts petroleum resin (Finton D-200).

(manufactured by Nippon Zeon Co., Ltd.) 7 parts carbon black 15 parts Coloring material layer composition (d
) Low molecular weight polyethylene wax (Sunwax 171-P, manufactured by Sanyo Chemical Co., Ltd.) (melting point 10
5°C) 35 parts Paraffin wax (Paraffin wax 155 manufactured by Nihon Seiro Co., Ltd.) (Melting point 68°C) 40 parts Styrene-ethylene
Butylene co-ffi combination (Krayton G-1957, manufactured by Shell Chemical Co., Ltd.) 4 parts Petroleum resin (Alcon P-125゜ manufactured by Arayo Chemical Co., Ltd.) 6 parts Carbon black 15 parts Comparative Example 1 Ethylene in coloring material layer composition (a) A comparative thermal transfer recording medium sample (E) was obtained in the same manner except that the amount of -ethyl acrylate copolymer was changed to 0.05 part.

Comparative Example 2 In colorant layer composition (b), aromatic hydrocarbon resin was added to 0.
．． A comparative thermal transfer recording medium sample (F) was obtained in the same manner except that 4 parts were used.

Comparative Example 3 A comparative thermal transfer recording medium sample (G) was obtained in the same manner except that in the colorant layer composition (C), the styrene-butadiene copolymer was changed to 6 parts and the petroleum resin was changed to 10 parts.

Comparative Example 4 Coloring material layer composition (d) styrene-ethylene
A comparative thermal transfer recording medium sample (11) was obtained in the same manner except that 6 parts of the butylene copolymer was used.

Comparative Example 5 Coloring material layer composition (e) (melting point 65°C) 5 parts (softening point 80°C) 10 parts carbon black 1 part kaolin
15 parts of the above coloring material layer composition (e)
A comparative thermal transfer recording medium sample (1) was obtained in the same manner as in Example 1.

The thermal transfer recording medium samples obtained in the above Examples and Comparative Examples were printed using a thermal printer (heating element density: 8 dots/mm).
Table 1 shows the results of printing on plain paper using a prototype machine equipped with a thin-film line thermal head (), with an applied power of 7 W per heating element and an application time of 0.5 milliseconds. The results shown are obtained.

1. A checkered pattern was printed on plain paper with a Bekk smoothness of 200 s'e c and observed with a magnifying glass. The ■ mark indicates that the edges of the print are sharp, and the ∆ mark indicates that the edges are slightly distorted.
The X marks were made using a three-step method that caused defects and blurring in the print.

Book 2: Rub it with a plastic eraser 5 times with normal force, and if the outside of the printing part is thin and undone, it will be marked with an SO mark.
The three-step method was used: Δ if the print was readable but the outside of the printing part was as dirty as the print part, and x if the print part was extremely dirty and sometimes the print was unreadable.

Book 3 Various kanji were printed on plain paper with a Beck smoothness of 200 seconds, and dirt on areas other than the printed areas was observed using a magnifying glass.

A three-step method was used: ◯ indicates no staining, Δ indicates slight staining, and X indicates significant staining.

Further, after each of the obtained heat-sensitive transfer recording media was strongly bent, the heat-melting coloring material layer was observed with a magnifying glass, and the results shown in Table 2 were obtained.

2nd Table 1: Mark O when no peeling of the heat-melting coloring material layer is observed.
A three-step method was used, with Δ indicating slight peeling of the heat-fusible colorant layer and × mark indicating significant peeling of the heat-fusible coloring material layer.

As is clear from Tables 1 and 2, the samples of the present invention have strong film strength, and transfer images with high resolution and good fixability can be obtained.
It can also be seen that the occurrence and growth of background stains can be suppressed.

Claims (2)

[Claims] (1) On the support, [1] a coloring agent, [2] a heat-melting substance, [3] a softening point or melting point of 50 to 130°C, a glass transition point of 45°C or more, and a breaking elongation of 10% or less. , a resin (A) having a melt viscosity of 1 x 10^2 to 1 x 10^5 cp at 150°C, a softening point or melting point of 80°C or higher, a glass transition point of 20°C or lower, and a breaking elongation of 50% or higher. In a heat-sensitive transfer recording medium having a heat-melt coloring material layer containing a resin component containing resin (B), the content of the heat-melting substance in the heat-melting coloring material layer is 15 to 95% by weight. and the content of the resin (A) is 0.5% by weight or more 10
% by weight, and the content of the resin (B) is 0.
A thermal transfer recording medium characterized in that the content is 1% by weight or more and less than 5% by weight. (2) The heat-sensitive transfer recording medium according to claim 1, wherein the heat-melting substance is a combination of at least one type of hard wax and at least one type of soft wax.