JPH04211992A - Sublimable thermal transfer material - Google Patents

Abstract

PURPOSE:To prevent the occurrence of deterioration in ink layer thermal transfer, ink layer shelf stability, and sensitivity to form an ideal full color image by using Yellow, Magenta, and Cyan dyes each having a specific Gram's absorptivity. CONSTITUTION:A thermal transfer material for transparent image-receiving film recording and multi-time recording is provided with Yellow, Magenta, Cyan, or Black ink layer formed by dispersing a sublimable dye in an organic binder on a substrate. In the sublimable thermal transfer material, Gram's absorptivity of the Yellow, Magenta, or Cyan main sublimable dye as shown by a formula is 150000 or more. As the sublimable dye, a dispersion dye or an oil-soluble dye, such as PSD-290(Y) or PSD-3(Y), sublimating or vaporizing at 60 deg.C is exemplified. For forming the ink layer, a composition made of the organic binder, the sublimable dye, a toluene, and an MEK is dispersed by a ball mill and applied on a PET film with a silicone resin heat-resistant layer provided on the rear surface thereof as the ink layer.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a sublimation type thermal transfer material, particularly an O
The present invention relates to a sublimation type thermal transfer material that can form high-density images on HP transparent image-receiving films, and a sublimation type thermal transfer material that can perform multiple recordings.

[Prior Art] Transmissive images, such as transparent originals for OHP, have half the optical path length of reflective images, so images produced using conventional reflective transfer materials have poor density. It is insufficient. Therefore, various proposals have been made to achieve higher density output than reflective transfer bodies, but each has its own problems and none has been satisfactory. For example,

i) Increase dye coverage. As the thickness of the ink layer inevitably increases, the sensitivity decreases. ii) increasing dye concentration; Although the thickness of the ink layer does not change, since the amount of binder in the ink layer becomes relatively small, the mechanical strength of the ink layer decreases, and the adhesive force between the ink layer and the substrate decreases. As a result, thermal transfer of the ink layer occurs, as well as dye crystallization during storage.
The problem was that the storage stability of images deteriorated due to dye precipitation on the surface of the ink layer. iii) Adding a low softening substance. Addition of a low-softening substance causes disadvantages such as thermal transfer of the ink layer and destruction of the ink layer due to a decrease in the mechanical strength of the ink layer during recording. Furthermore, there is a problem that the storage stability of the ink layer is also reduced. Further, thermal transfer bodies for multiple recording have been proposed, but the conventionally proposed ones have the problems i) and ii) above.

0003

[Problems to be Solved by the Invention] The present invention solves the following problems:
An object of the present invention is to provide a transfer material capable of high-density dyeing that is free from drawbacks such as thermal transfer of an ink layer and reduced storage stability of an ink layer, satisfies OHP specifications, and has an improved number of recordable times. It is.

[Means for Solving the Problems] The structure of the present invention for solving the above problems includes a yellow, magenta, cyan, or black ink layer formed by dispersing a sublimable dye in an organic binder on a substrate. In the sublimation type thermal transfer material for transparent image-receiving film recording and multi-time recording, the gram extinction coefficient of each of the main sublimable dyes of yellow, magenta, and cyan is 150.
,000 or more. The above gram extinction coefficient is defined by the following formula. Therefore, by knowing the transmittance of a solution with a known dye concentration, the gram extinction coefficient of the dye can be determined.

[0004] In the sublimation type transfer material, as mentioned in the section of the prior art, there is a limit to the amount of dye that can be contained in the ink layer. Therefore, recording density (O.D.
．． ), a small amount of dye can be used to increase the O. D. This objective can be achieved by using a dye with a large gram extinction coefficient. By the way, at present, in a transfer medium that prints yellow, magenta, cyan, or black sequentially and outputs a full-color image, the O. D. Output capabilities must be equal. Therefore, a transfer material in which the main dye of each color has a gram extinction coefficient of 150,000 or more is required. Black dye does not exist alone; it produces yellow,
Create black by mixing magenta and cyan. Therefore, the gram extinction coefficient of the black dye produced by mixing is determined by measuring a mixture of the component yellow, magenta, and cyan dyes at a predetermined mixing ratio, which is regarded as a monochromatic color.

To explain the present invention in detail, the recording medium used has a gram extinction coefficient of 15 as a sublimable dye.
0,000 or more and that sublimates or vaporizes at 60°C or more, and is mainly used in the field of thermal transfer recording such as disperse dyes and oil-soluble dyes, such as PSD.
-290(Y), PSD-3(Y), Yellow 1
011, Yellow 1012 (Sumitomo Chemical), For
on Brilliant Yellow S-6GL
(SANDOZ), Yellow RP, Yellow
VP (Mitsui Toatsu Dye), KST Yellow 96
3. KST AG (Nippon Kayaku), Macrolex Y
yellow 6G (BAYER), PlstYello
w 8040 (Arimoto Chemical), HM1041 (Mitsui Toatsu Dye Chemical), Sudan Red 380 (BASF),
Mitsui Blue HM-1034 (Mitsui Toatsu), KST Blue K-FL (Nippon Kayaku), Fo
ron Brilliant Blue SR (
SANDOZ), HSO-144 (Mitsui Toatsu Dye Chemical), etc. These dyes may be used alone or in combination with dyes that sublime and vaporize at temperatures above 60° C. and have a gram extinction coefficient of 150,000 or less. Examples of binders that hold sublimable dyes include vinyl chloride resin, vinyl acetate resin, polyamide, polyethylene, polycarbonate, polystyrene, polypropylene, acrylic resin, phenol resin, polyester, polyurethane, epoxy resin, silicone resin, and fluorine resin. resin, butyral resin,
Examples include melamine resin, natural rubber, synthetic rubber, polyvinyl alcohol, and cellulose resin. These resins can be used alone, but several types may be mixed or a copolymer may be used.

[0006] Also, the dye concentration is 5 to 80% by weight,
Preferably it is about 10 to 60% by weight. The ink layer thickness is 0.1 to 30 μm, preferably 0.5 to 2.0 μm. Further, when using the n-fold mode method (speed difference mode method) as a multi-recording method, a cured resin is preferable, and more preferably one having a curing reaction product of an isocyanate and a binder having an OH group as a binder. is preferable, and examples of the binder polymer compound having active hydrogen used in the urethane formation reaction include polyvinyl butyral, polyvinyl acetal, polyurethane polyol, polyether polyol, polyester polyol, acrylic, acrylic-polyester copolymer, and alkyd. , silicone polyester, and those in which the epoxy group of epoxy is ring-opened with an alkanolamine to form an -OH group.As the isocyanate, di- or tolylene diisocyanate is effective, such as 2,4-tolylene diisocyanate. , 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, triphenylmethane triisocyanate, isophorone diisocyanate, bisisocyanate methylcyclohexane, trimethylhexamethylene diisocyanate, and the like. Among these, polyvinyl butyral is particularly desirable because it has a rate interaction with the dye used and can achieve both barrier properties against dye diffusion and ribbon storage stability. Further, as the isocyanate, commercially available Coronate L (manufactured by Nippon Polyurethane Co., Ltd.) and Takenate D (manufactured by Takeda Pharmaceutical Company) are preferable because they are easy to handle. The mixing ratio of the two is preferably in the range of 0.1:1 to 1:1 of the -NCO group of the isocyanate and the -OH group of the compound having active hydrogen.

The dye concentration is usually about 5 to 80% by weight, preferably about 10 to 60% by weight. The ink layer thickness is 0.1 to 30 μm, preferably 1.0 to 20 μm. In addition, when recording by the n-times mode method as a multi-recording method, it is preferable to mix a substance having slipperiness or release properties into the ink layer.
Examples of lubricating substances include petroleum-based lubricating oils such as liquid paraffin, synthetic lubricating oils such as hydrogen halides, diester oils, silicone oils, and fluorosilicone oils, and various modified silicone oils (epoxy-modified, amino-modified, alkyl silicone-based lubricating substances such as copolymers of organic compounds such as polyoxyalkylene glycol and silicone, various fluorine-based surfactants such as fluoroalkyl compounds, trifluorochloroethylene low polymers, etc. fluorine-based lubricating substances, waxes such as paraffin wax and polyethylene wax, higher fatty acids, higher fatty alcohols, higher fatty acid amides, higher fatty acid esters, higher fatty acid salts, and particles having the above-mentioned lubricity or thermal release properties. There are various types of particles mentioned above.

The content of the substance having lubricity or mold release properties in the dye transfer contributing layer is preferably 5 to 30% by weight. If the content is less than 5%, the mold releasability or adhesion prevention effect will be insufficient, while if it exceeds 30%, problems will occur in storage stability. In addition, as a base sheet, condenser paper, polyester film, polystyrene film,
Films such as polysulfone film, polyimide film, polyamide film, etc. are used, and a conventional adhesive layer etc. may be provided between the base sheet and the ink layer as necessary, and a conventional adhesive layer etc. may be provided on the back side of the base sheet. A conventional heat-resistant lubricant layer may be provided depending on the requirements. Furthermore, as described in JP-A-1-586 which satisfies the above conditions, the ink layer has two layers: a dye transfer contributing layer (a layer that contributes to image formation) and a dye supply layer (a layer that supplies dye to the contributing layer). The laminated type with functionally separated layers and the single-layer type with dispersed particulate dye as in JP-A-1-157891 are particularly excellent as transfer bodies in the n-times mode method and n-times mode method for multipurpose purposes. This can be said to be a very good composition.

[0009]

【Example】

The present invention will be explained in more detail with reference to Examples below. Note that all amounts (parts) of each component described in Examples are parts by weight. (Ink layer formulation) Organic binder: Polyvinyl butyral BX-1 [Sekisui Chemical Co., Ltd.] 10 parts Sublimable dye (the name and amount are as shown in Table 1 below) Toluene

95
Part Methyl ethyl ketone

After dispersing 95 parts of the above-prescribed composition in a ball mill for 24 hours, a 1-μm-thick ink layer was formed on a 6-μm-thick polyethylene terephthalate film on which a 1-μm-thick silicone resin heat-resistant layer was formed using a wire bar.

0010

[Table 1]

[0011]

Comparative Example I-3 was the same as Comparative Example I-1 except that the ink layer thickness was increased to 1.5. As Comparative Example I-4, a low softening wax, silicone wax D, was used in the ink layer.
The procedure was the same as Comparative Example I-1 except that 3 parts of CQ5-0158A were mixed. Further, a mixture having the following composition was thoroughly mixed and dispersed to prepare a coating liquid for the intermediate layer [liquid A] and a coating liquid for the receptor layer [liquid B]. [Liquid A] Polyester resin [trade name Vylon 200; manufactured by Toyobo Co., Ltd.] 100 parts Isocyanate [trade name Burnock DN-950; manufactured by Dainippon Ink and Chemicals Co., Ltd.]
10 parts toluene

30
0 parts methyl ethyl ketone

300 parts [Liquid B] Vinyl chloride/vinyl acetate copolymer resin (trade name VY
HH; manufactured by Union Carbide)
100 parts Amino-modified silicone [trade name SF8417; Toray Silicone (
Co., Ltd.]
1 part toluene

28
0 parts methyl ethyl ketone

280 copies

[0013] Next, [Liquid A] and [Liquid B] were coated with a polyethylene terephthalate film [trade name: Lumirror T60] with a thickness of about 100 μm using a wire bar.
manufactured by Toray Industries, Inc.] and dried for 1 minute at a drying temperature of 90° C. to form an intermediate layer and a receptor layer each having a thickness of about 3 μm, thereby producing an image-receiving medium of the present invention. Furthermore, Examples I-1 to 3 and Comparative Examples I-1 to 3 were prepared under the following conditions.
was recorded. Applied power: 432 mw/dot Thermal head: Resolution 6 dots/mm Recording time: 7.
0 ms Applied energy: 3.02 mj/dot The resulting recording characteristics of Examples I-1 to I-3 and Comparative Example I-1 are shown in FIGS.
4. In addition, the transmission density is measured using Macbeth transmission densitometer RD-
According to 504. Moreover, Comparative Example I-2 has a lower O.D. than Comparative Example I-1. D. part is low and high O. D. Department has increased. Comparative Example I-3 had an overall O. D. was higher, but Example I-
I couldn't get to level 1, 2, or 3. Comparative example I-4
is approximately the same level of O. as in Example I-2. D. Met. Further, the storage test was carried out at 60° C., 100 hours, and 50% RH, and the ink layer and heat-resistant layer were stacked and stored under a load of 3 kg/A4.

Examples II-1 to II-3, Comparative Example II-1 (intermediate adhesive layer formulation)

Parts by weight Polyvinyl butyral BX-1 [Sekisui Chemical Co., Ltd.] 1
0 Diisocyanate Coronate L [Japan Polyurethane Industries Co., Ltd.] 5 Toluene

95
Methyl ethyl ketone

95 (Ink layer formulation) Polyvinyl butyral BX-1

7 Sublimable dye

X in Table 2 Amino-modified silicone oil SF8417
2 Epoxy modified silicone oil SF8411
2 Diisocyanate Coronate L
2
toluene

70 Methyl ethyl ketone

70

After dispersing the composition of the above formulation in a ball mill for 24 hours, a 1.0 μm thick intermediate adhesive layer was formed using a wire bar on a 6 μm thick aromatic polyamide film on which a 1 μm thick silicone resin heat-resistant layer was formed on the back side. Further, an ink layer with a thickness of 4.5 μm was formed thereon. Examples II-4 to II-6, Comparative Example II-2 (Formulation of first layer)

Part by weight Polyvinyl butyral resin BX-1

7 Sublimable dye

Y in Table 2 Polyethylene oxide
3
Coronate L

2 Toluene

95 Methyl ethyl ketone

95 (second layer prescription)

Part by weight Polyvinyl butyral resin BX-1
10 Sublimable dye

Z in Table 2
Amino modified silicone oil SF8411

1.5 Epoxy modified silicone oil SF841
7
1.5 Coronate L

2 Toluene


95 Methyl ethyl ketone

95 The composition of the above formulation was applied onto a film provided with an intermediate adhesive layer in the same manner as in Example II-1, with the first layer having a thickness of 4.5 μm and the second layer having a thickness of 1
．． It was formed to have a thickness of 0 μm, and everything else was carried out in the same manner as in Example II-1.

[0016]

[Table 2]

[0017]

[0018]

[0019]

Further, as an image-receiving paper, a mixture having the following composition was thoroughly mixed and dispersed to prepare a dye-receiving layer coating liquid [A]. [Liquid A] Vinyl chloride/vinyl acetate/vinyl alcohol copolymer (VAGH; manufactured by Union Carbide)
1
0 parts Isocyanate (Coronate L; manufactured by Nippon Polyurethane Industries, Ltd.) 5 parts Amino-modified silicone (SF-8417; manufactured by Toray Silicone Co., Ltd.)
0.5 part epoxy modified silicone (SF-84
11; Manufactured by Toray Silicone Co., Ltd.) 0.5 parts Toluene

40 parts methyl ethyl ketone

Next, apply 40 copies of [Liquid A] to synthetic paper (YUPO FPG) with a thickness of about 150 μm using a wire bar.
-150; manufactured by Oji Yuka Synthetic Paper Co., Ltd.) and dried for 1 minute at a drying temperature of 75°C to form a dye-receiving layer with a thickness of approximately 5 μm, and then stored at 80°C for 3 hours. This was cured to produce an image receiving medium of the present invention.

Transfer images were formed under the following conditions using the thermal transfer members and image receiving medium shown in each of the above Examples and Comparative Examples. Applied power: 158 mW/dot Applied energy: 0.76 mJ/dot O. Shows D characteristics. The recording results are shown in the graphs of FIGS. 5-13. That is, FIGS. 5 to 7 show the test results of Examples II-1 to 3, respectively, FIG. 8 shows the test results of Comparative Example II-1, and FIGS. 9 to 11
are the test results of Examples II-4 to II-6, respectively, and FIG. 12 is the test result of Comparative Example II-2. The recorded density (O.D.) is Macbeth Densitometer RD 91.
8.

[0022]

Effect of the invention: As explained above, the gram extinction coefficient is 15.
By using yellow, magenta, and cyan dyes of 0,000 or more, thermal transfer of the ink layer, deterioration of ink layer storage stability, deterioration of sensitivity, etc. do not occur, and high O.D. D. It can output yellow, magenta, and cyan O. D. Since the performance was also uniform, good full-color images were obtained. In addition, each color can be used without waste when recording multiple times.

[Brief explanation of the drawing]

[Figure 1]

[Figure 2]

FIG. 3 is a graph showing the recording characteristics of Examples I-1 to I-3 of the present invention, respectively;

FIG. 4 is a graph showing recording characteristics of Comparative Example I-1.

[Figure 5]

[Figure 6]

[Figure 7]

[Figure 8]

[Figure 9]

[Figure 10]

[Figure 11]

12 is a graph showing the test results of Example II-1 to Comparative Example II-2 in the order shown in Table 2. FIG.

Claims (2)

[Claims] Claim 1. A sublimation type thermal transfer material for transparent image-receiving film recording, which has a yellow, magenta, cyan, or black ink layer formed by dispersing a sublimable dye in an organic binder on a substrate. A sublimation type thermal transfer material, characterized in that each main sublimable dye of cyan has a gram extinction coefficient of 150,000 or more. 2. A sublimation thermal transfer material for multi-time recording, which has a yellow, magenta, cyan, or black ink layer formed by dispersing a sublimable dye in an organic binder on a substrate. A sublimation type thermal transfer material, characterized in that each of the main sublimable dyes has a gram extinction coefficient of 150,000 or more.