JPH0510238B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a heat-sensitive transfer recording method for obtaining a transferred recorded image on plain paper or the like using a heat-sensitive transfer recording medium having a coloring material supply layer and an intermediate recording sheet having a heat-melting image-receiving layer. More specifically, the present invention relates to a heat-sensitive transfer recording method that uses a heat-sensitive transfer recording material that has excellent shelf life and can produce a recorded image on plain paper that has good shelf life. [Prior art] Dye is transferred from a thermal transfer recording medium onto a recording sheet using a thermal recording device having a heat source such as a thermal head consisting of a thick film resistor, thin film resistor, or semiconductor resistor, or a laser or a xenon lamp. Various techniques for forming recorded images have been proposed in the past, and some have been implemented as thermal printers and thermal facsimile techniques. For example, JP-A No. 54-68253 and JP-A No. 57-160691 disclose a thermal transfer film in which an ink component that melts when heated is contained in a microporous layer containing a resin component as a binder. A technique has been disclosed in which a recording medium is used to form a transferred recorded image multiple times on plain paper, but with this recording method, the formed transferred recorded image has noticeable unevenness and is not suitable for obtaining a so-called solid image. It wasn't. On the other hand, JP-A-59-14994 and other documents describe a thermal transfer recording medium using a polymer composition with a melting point or softening point of 100° C. or higher together with a dye, and it is possible to obtain an even transferred recorded image. It is disclosed that it is possible. However, since this recording technique uses a sublimable dye, not only is there a drawback that the storage stability of the thermal transfer recording medium is poor, but also the storage stability of the transferred recorded image obtained by thermal transfer is also poor. Therefore, the present applicant first proposed the technology shown in the patent application filed on April 2, 1980. The proposed technology is
The coloring material supply layer of the thermal transfer recording medium and the heat-melting image receiving layer of the recording sheet are stacked facing each other, and thermal energy contained in the image-receiving layer is removed by applying thermal energy according to the image information to be recorded. A heat-sensitive transfer recording method in which a non-sublimable colorant contained in the colorant supply layer is dissolved or dispersed in the meltable substance of the image receiving layer to form a transferred recorded image on the recording sheet. This is a thermal transfer recording method in which a thermal transfer recording material with excellent raw storage stability can be used, and the storage stability of the transferred recorded image obtained by thermal transfer is also good. However, the previously proposed technique has the disadvantage that it is impossible to use plain paper as the recording sheet. [Problems to be Solved by the Invention] The present invention has been made in view of the above, and it is possible to use a heat-sensitive transfer recording material with excellent shelf life, and it is also possible to preserve the transferred recorded image obtained by heat transfer. The technical problem is to provide a transfer recording image that has good properties and can be transferred onto plain paper. [Means for Solving the Problems] The technical means of the present invention for solving the above-mentioned technical problems includes a colorant supply layer mainly containing a non-sublimable colorant and a thermally stable thermoplastic polymer substance. The colorant supply layer of the heat-sensitive transfer recording medium and the heat-melting image-receiving layer of the intermediate recording sheet are stacked facing each other, and heat contained in the image-receiving layer is removed by applying thermal energy according to the image information to be recorded. Melting a fusible substance and transferring the non-sublimable colorant contained in the coloring material supply layer into the heat-fusible substance of the image receiving layer to obtain an intermediate recorded image transferred to the intermediate recording sheet; is thermally transferred to the final recording sheet. In the present invention, the means for applying thermal energy according to the image information to be recorded may be a thermal recording device having a heat source such as a thermal head or a thermal pen to apply thermal energy from the support side of the intermediate recording sheet. Alternatively, thermal energy may be applied from the support side of the thermal transfer recording medium,
Thermal energy may be applied from both the support side of the intermediate recording sheet and the support side of the thermal transfer recording medium. In addition, the means for thermally transferring the intermediate transfer recorded image obtained on the intermediate recording sheet to the final recording sheet such as plain paper uses a heat source such as a hot roll or an electric iron to apply thermal energy from the support side of the intermediate recording sheet. Alternatively, heat energy may be applied from the final recording sheet side such as plain paper,
Thermal energy may be applied both from the support side of the intermediate recording sheet and from the side of the final recording sheet such as plain paper. The present invention will be explained in more detail below, but first,
The thermal transfer recording medium used in the present invention will be explained. The thermal transfer recording medium used in the present invention has at least one coloring material supply layer on a support. The colorant supply layer mainly contains a non-sublimable colorant and a thermoplastic polymeric substance. [Colorant] The non-sublimable colorant is a non-sublimable substance that can move (dissolve or disperse) into the heat-fusible substance of the image-receiving layer during heating recording and has a color. The material may be either a substance that absorbs light at visible wavelengths (400 nm to 800 nm) or a substance that forms a substance that absorbs light in the visible light range. They are generally called dyes and are suitable for thermal transfer recording media. Among synthetic pigments called dyes, natural pigments called animal pigments or vegetable pigments, non-sublimable ones are used. The non-sublimable coloring agent used in the present invention is a colorant excluding sublimable colorants (including those that vaporize with melting or dissolution) used in mordant dyes and the like. The presence or absence of sublimation of the colorant used in the present invention is as follows:
You can check this with a simple test like the one below.
A spacer is interposed between the colorant and the image-receiving layer, that is, an air layer is provided between the colorant and the image-receiving layer so that they do not come into direct contact with each other. The spacer may be, for example, a thin, porous material such as tissue paper. The image-receiving layer at this time is selected from water-soluble polymers, oil-soluble polymers, paper, glass, waxy substances, and other solid materials in which the colorant can be adsorbed or dissolved. Then, heat energy is applied to the colorant by applying a heating plate (for example, 100°C). Therefore, if the colorant is non-sublimable, it will not be transferred to the image-receiving layer very much or will be barely transferred to the image-receiving layer in the above test, regardless of the properties of the image-receiving layer. On the other hand, in the case of sublimation, it is transferred. Preferred non-sublimable colorants for the present invention include non-sublimable colorants such as direct dyes, acid dyes, basic dyes, disperse dyes, and oil-soluble metal complex dyes, and these dyes are not ballasted. It's okay. Basic dyes preferably used as the non-sublimable colorant of the present invention include, for example, crystal violet (CI42555), malachite green (C.
I.42000), Methyl Violet (CI42535), Victoria Blue (CI44045), Mazienta (C.
Triphenylmethane dyes such as I.42510), diphenylmethane dyes such as Auramine (CI655), Astraphloxine FF (CI48070), Eisenkatylon Yellow 3GLH (Hodogaya Chemical Co., Ltd. product, CI48055), Eisenkathyronretsu Do 6BH
(CI48020) Astrazone Golden Yellow
Methine and azamethine dyes such as GL (Bayer product, CI48054), Rhodamine B (C.
I.45170), xanthene dyes such as Rhodamine 6G (CI45160), Astrazone Blue GL (C.
I.11052), Astrazone Red F3BL (CI11055)
Thiazole azo and triazole azo dyes such as Eisenkathylon Blue 5GH (CI11085),
Quinoneimine dyes such as methylenebrae (CI52015), Eisencatylone Red GTLH (C.
I.11085), Cevron Yellow 3RL (DuPont product, CI11087), Astrazone Blue FGL (C.
Examples include insulating azo dyes and anthraquinone dyes having an onium group at the structural end, such as I.61512). Examples of oil-soluble metal complex dyes include symmetrical 1:2 type azo metal complex dyes, asymmetrical 1:2 type azo metal complex dyes, 1:1 type azo metal complex dyes, azomethine metal complex dyes, and formazan type metal complex dyes. Examples include metal complex dyes, metal phthalocyanine dyes, and organic base salts of these dyes. Specifically, Eisenspiron Yellow 3RH (Hodogaya Chemical Co. product, CI Solvent Yellow 25), Zapon Fast Yellow R (BASF product, CI18690), Eisenspiron Orange 2RH (CI Solvent Orange 40), Zapon Fast Scarlet B (C.
I.12783), Eisenspiron Red GEH (CI Solvent Red 84), Zaponphastrone BE
(CI12715), Zapon Fast Violet BE (C.
I.12196), Cyanine Blue BB (Sumitomo Chemical Co., Ltd. product,
CI74160), Variable Asto Black #3804 (Orient Chemical Co., Ltd. product, CI12195), Eisenspiron Yellow 3RH Special (CI Solvent Yellow 25:1), Eisenspiron Orange 2RH Special (CI Solvent Orange 40:1), Eisenspiron Blue 2BNH (CI Solvent Blue 117), Zapon Fuasto Blue HFL (C.
I.74350), Eisenspiron Black BH Special (CI Solvent Black 22:1), etc. Acidic dyes such as CI Acid Yellow
19, CI Assisted Red 37, CI Assisted Blue
62, CI Acid Orange 10, CI Acid Blue 83, CI Acid Black 01, etc. Direct dyes are CI Direct Yellow 44, CI
Direct Yellow 142, CI Direct Yellow 12, CI Direct Blue 15, CI Direct Blue 25, CI Direct Blue 249, CI Direct Red 81, CI Direct Red 9, CI Direct Red 31, CI Direct Black 154,
Examples include CI Direct Black 17. The disperse dyes are CI Dispose Yellow 5, C.
I. Dispose Yellow 51, CI Dispose Yellow 64, CI Dispose Red 43, CI Dispose Red 54, CI Dispose Red 135,
Examples include CI Dayspose Blue 56, CI Dayspose Blue 73, and CI Dayspose 91. The ballasted dyes used in the present invention are dyes such as azo dyes, azomethine dyes, anthraquinone dyes, naphthoquinone dyes, sterine dyes, quinophthalo dyes, and phthalocyanine dyes (solid or semisolid at room temperature and migratory by heating). Non-sublimation or non-vaporization is preferable.) In the mother nucleus,
A dye having at least one ballast group with a melting point of 300°C or lower is preferable, and one with a melting point of 250°C or lower is particularly preferable. The ballast group of the present invention is a group that is highly soluble in heat-fusible substances, such as an alkyl group, a cycloalkyl group, an aralkyl group, an alkoxy group, an alkylsulfonylamino group, an alkylsulfonyl group, a hydroxylalkyl group, a cyanoalkyl group, and an alkoxycarbonylalkyl group. A group having an alkyl group having 6 or more carbon atoms or an alkylene group such as a group, an alkoxyalkyl group, or an alkylthio group. Especially the number of carbon atoms in the molecule is 6.
A balanced group having at least one of the above alkyl groups is preferred. At the end of this specification, structural examples of ballasted dyes used in the present invention are listed, but the present invention is not limited thereto. Examples of thermoplastic polymer substances contained in the coloring material supply layer include casein, gelatin (including derivative gelatin), polyvinyl alcohol, polyvinyl butyral, methyl cellulose, gum arabic, polyester such as polyethylene terephthalate, polyvinyl formal, polypropylene,
Polystyrene, polycarbonate, polyvinyl chloride, ethyl cellulose, acetyl cellulose, nylon, polyethylene, phenolic resin,
A thermally stable material such as polyacrylonitrile or polysulfone is used. These may be used alone or in combination. In the present invention, the image-receiving layer contains a heat-melting substance (low melting point substance) that can dissolve or disperse the colorant when melted. The heat-melting substance is 45℃
This refers to substances that have a melting point (measured using Yanagimoto MPJ-2 model) in the range from Specifically, plant waxes such as carnauba wax, tree wax, auricilla wax, and espal wax, animal waxes such as beeswax, insect wax, serrata wax, spermaceti wax, paraffin wax, microcrystalline wax, and ester wax. In addition to waxes such as petroleum waxes such as , oxidized waxes, mineral waxes such as montan wax, ozokerite, and ceresin, palmitic acid, stearic acid,
Examples include higher fatty acids such as margaric acid, higher alcohols such as eicosanol, higher fatty acid esters such as cetyl palmitate and myricyl palmitate, oleylamide, and stearylamide. Particularly preferred are oleylamide, carnauba wax, and ester wax, and these low melting point compounds may be used alone or in combination of two or more. The heat-fusible substance used in the colorant image-receiving layer of the present invention is particularly preferably a combination of a hard wax and a soft wax (one type or two or more types of each). Hard wax [Penetration at 25℃ (100g) (JIS K2530
by. ) is less than 8.
Ester wax (natural ester wax such as carnauba wax, Montan wax, Hoechst Wax E, F, KP, KPS, BJ,
Synthetic ester waxes such as OP, OM,
NPS-9210, NPS-6115, Toyo Petrolite PETRONABA・C, CARDIS314, etc.), low molecular weight polyethylene wax (especially molecular weight 300~
1000, manufactured by Toyo Petrolite Co., Ltd.
POLYWAX 500 and 655, etc.), acid waxes (Hoechst Wax S and LP, etc. manufactured by Hoechst), and the like. Also, soft wax [25
Examples of waxes with a penetration degree (according to JIS K2530) of 8 or higher at °C (100 g) include microcrystalline waxes (Nisseki Microwaxes 155 and 180 (manufactured by Nippon Oil Corporation), HI-MIC- 1080,
HI−MIC−2065, HI−MIC−2095, HI−MIC−
1070, HI-MIC-1045, HI-MIC-2045 (manufactured by Nippon Seirosha), STAR WAX 100, BE
SQUARE175, 185, VICTORY,
ULTRAFLEX (manufactured by Toyo Petrolite Co., Ltd.), stearic acid, behenic acid, stearyl alcohol, white wax, beeswax, dodecyl stearate, stearone, sorbitan monostearate, polyoxyethylene monostearate, or Diacarna 30
and Diakaruna PA30L (manufactured by Mitsubishi Kasei Corporation). In addition, when such hard wax and soft wax are used in combination, the weight ratio used may be 1:9 to 9:1 (more preferably 2:8 to 8:2). The heating temperature when heating the heat-sensitive transfer recording medium of the present invention for transfer recording can be determined by taking into account the relationship with the heating time and the melting point of the substance used in the heat-melting image-receiving layer. (25°C) or higher, more preferably about 45°C or higher. At least one of the supports of the recording medium and intermediate recording sheet of the present invention is made of the thinner support shown below. If only one of the supports consists of a thin support, the other may consist of a non-thin support as shown below. [Thinner Support] As the support for the thermal transfer recording medium and/or intermediate recording sheet of the present invention, it is desirable to use a support that has heat-resistant strength, high dimensional stability, and high surface smoothness. Heat-resistant strength requires strength and dimensional stability to maintain the toughness of the support without becoming softened or plasticized by the heating temperature of a heat source such as a thermal head, and surface smoothness requires the coloring material on the support. Sufficient smoothness is desired so that the non-sublimable colorant contained in the supply layer exhibits a good transfer rate. The smoothness was determined by a smoothness test using a Beck testing machine (JIS P 8119).
100sec or more is good, and 300sec or more is good.
Images with better transfer rate and reproducibility can be obtained. Materials include, for example, papers such as plain paper, synthetic paper, laminated paper, capacitor paper, and coated paper; resin films such as polyethylene, polyethylene terephthalate, polystyrene, polypropylene, polyester, and polyimide; and paper-resin film composites. , metal sheets such as aluminum foil, etc. are all suitably used. The thickness of the support should be 20 μm or less, especially 2 μm or less in order to obtain good thermal conductivity.
Preferably it is ~10 μm. [Support that is not thin] As the support for the heat-sensitive transfer recording medium and/or intermediate recording sheet of the present invention, a support that has heat-resistant strength and high smoothness is desirable. The heat-resistant strength and smoothness are the same as those described for the thinner support, and the specific examples of the material are also the same. Other specific examples of the material include ceramics, porcelain, glassware, and fibers such as cloth. The heat-melting image-receiving layer provided on the support may partially penetrate into the support,
A portion may soak in during heating recording. [Method of retransfer] After applying thermal energy according to the image information to move the non-sublimable colorant from the coloring material supply layer to the heat-melting image receiving layer, the image receiving layer having the transferred intermediate recorded image and the final recording are transferred. By overlapping the sheets and applying thermal energy again, the image is transferred to the final recording sheet (plain paper, glass, metal, resin, rubber, polymer surface, etc.). Retransfer can be performed using an iron, a hot roll, a thermal head, etc., regardless of the image information, or by applying thermal energy to the area that requires retransfer.This transfer principle can be achieved using ordinary thermal transfer sheet transfer technology. can be used as a reference. [Effects of the Invention] Since the present invention has the above configuration and operation, the technical problems of the present invention described above can be solved,
So-called solid images can be obtained with high density and evenly, character images can be obtained easily, and furthermore,
Due to its high sensitivity, it is possible to save the amount of thermal energy required by a thermal pen, etc., or to record heat in a short time. In particular, according to the present invention, by using a non-sublimable colorant, the thermal transfer recording medium used has good shelf life, and the recorded images obtained by thermal transfer also have excellent shelf life. . Furthermore, a recorded image (print) can be obtained on plain paper, and thermal transfer recording can be performed two or more times from the image-receiving layer onto the plain paper. [Example] Preferred examples of the present invention will be shown below, but the present invention is not limited thereto. Example 1 On a 5.8 μm polyethylene terephthalate film support, a liquid containing the coloring agent and thermoplastic polymer substance shown in Table 1 below was applied using a wire bar to give a dry film thickness of 1.0 μm. A material supply layer was provided. On another 5.8 μm polyethylene terephthalate film support, an image-receiving layer having a dry film thickness of 4.0 μm and consisting of a heat-melting material shown in Table 1 was provided. Immediately after each sample of the thermal transfer recording medium was manufactured in this manner, the following thermal transfer recording test was conducted. That is, the prepared image-receiving layer and coloring material supply layer were stacked facing each other, and using a thermal printer (a prototype machine equipped with a thin-film line thermal head with a heating element density of 8 dots/mm) from the support side of the image-receiving layer sheet, The thermal transfer recording test was then carried out twice. The recording conditions are as follows. Recording conditions Applied power (w/dot) 0.5 Applied pulse period (us) 800 Applied pulse duty (%) 50 Line period (ms) 25 Paper feeding speed (mm/s) 7.7 Platen pressing pressure (Kg) 5 After recording, optical The transmission density was measured. In addition, the first
The table shows the compositions of the coloring material supply layer and the image receiving layer, and the results are shown in Tables 2 and 3.

【table】

[Table] Also, stack multiple sheets of each sample with the coloring material supply layer facing up, place a load (3 g/cm ² ) on them, and heat them at 30°C for 1 hour.
After being left for several months, transcription and recording was performed in the same manner as above.
The results are also listed in Table 2.

[Table] Layer the image-receiving layer of the first transfer above on plain paper (Beck smoothness 100 seconds) and transfer with an iron (150℃, 2 seconds)
Then, the optical reflection density was measured. The results are shown in Table 3.

[Table] * Re-transfer reflection density Example 2 A thermal transfer recording test was conducted in the same manner as in Example 1. Table 4 shows the compositions of the coloring material supply layer and image receiving layer, and Tables 5 and 6 show the results.

【table】

【table】

[Table] * Re-transfer transmission density In this example, the only difference was that the heating direction was performed from the support side of the coloring material supply layer.
Regarding the sample of the present invention, good results substantially similar to those of this example were obtained. As is clear from the above examples, according to the present invention, it is possible to obtain a transfer image using a non-sublimable dye on plain paper with excellent shelf life and little loss of density even in the second printing. I understand.

Claims (1)

[Claims] 1. Thermal melting of a colorant supply layer and an intermediate recording sheet of a thermal transfer recording medium having a colorant supply layer mainly containing a non-sublimable colorant and a thermally stable thermoplastic polymer substance. The non-sublimated material contained in the coloring material supplying layer is stacked face-to-face and the heat-melting material contained in the image-receiving layer is melted by applying thermal energy according to the image information to be recorded. transferring a coloring agent into the heat-fusible substance of the image-receiving layer;
A thermal transfer recording method in which a transferred intermediate recorded image is obtained on the intermediate recording sheet, and the intermediate recorded image is thermally transferred to a final recording sheet. 2. The thermal transfer recording method according to claim 1, wherein thermal energy is applied from the support side of the intermediate recording sheet in accordance with the image information to be recorded. 3. The thermal transfer recording method according to claim 1, wherein thermal energy is applied from the support side of the thermal transfer recording medium in accordance with the image information to be recorded. 4. The thermal transfer recording method according to claim 1, 2 or 3, wherein the final recording sheet is plain paper.