Thermal transfer image-receiving material

Disclosed is a thermal transfer image-receiving material comprising a support which has thereon an image-receiving layerr for receiving a dye transferred by heat application from a application from a thermal transfer dye-donating material and for forming an image. The image receiving layer comprises a fluorine-containing high-molecular weight compound, a fluorine-containing surfactant, and a matting agent. Such a transfer material produces a printed color image which has excellent clarity and resolution.

FIELD OF THE INVENTION 
The present invention relates to a thermal transfer image-receiving 
material for use in thermal transfer recording. More particularly, it 
relates to a thermal transfer image-receiving material which, when used in 
a thermal transfer recording together with a thermal transfer dye-donating 
material, does not suffer heat fusion to the dye-donating material. The 
image-recording material can be kept in close contact with the 
dye-donating material during the thermal transfer, producing no 
abnormality in the resulting image. 
BACKGROUND OF THE INVENTION 
With the rapid growth of the information industries, various 
information-processing systems have recently been developed and recording 
techniques and apparatuses suited for each information-processing system 
have been developed and adopted. Thermal transfer recording, which is one 
such recording technique, is advantageous in that the equipment therefor 
is light-weight, compact, and noiseless and its operation and maintenance 
are easy. Further, this recording technique is easily applicable to color 
recording, and it has consequently been extensively used in recent years. 
This thermal transfer recording technique is roughly divided into two 
types, a thermal fusion type and a thermal transfer type. In the latter 
technique, a thermal transfer dye-donating material comprising a support 
having a dye-donating layer containing a binder and a heat-transfer dye is 
superposed on a thermal transfer image-receiving material. Heat is applied 
from the support side of the dye-donating material, thereby transferring 
the heat-transfer dye to the recording medium (thermal transfer 
image-receiving material) in accordance with the heat pattern applied to 
obtain a transferred image. 
The heat-transfer dye discussed is a dye which can transfer from a thermal 
transfer dye-donating material to a thermal transfer image-receiving 
material by means of sublimation or diffusion into the medium. 
However, the thermal transfer image-receiving material used in the thermal 
transfer recording techniques of this type has the following problems. 
When the thermal transfer image-receiving material is superposed on a 
thermal transfer dye- donating material and the heat-transfer dye is 
transferred to the image-receiving material by heat application, the two 
materials are fused often to each other and, as a result, difficulties are 
encountered in peeling the two materials from each other after thermal 
transfer. Additionally, there are cases in which even if the two materials 
are readily peeled from each other, the surface layer of the dye-donating 
material been coated with the dye-donating layer adheres to the 
image-receiving material surface, resulting in impaired image quality or 
making the conveyance of the image-receiving material within the printer 
difficult. This trouble arises frequently, particularly when thermal 
transfer is conducted at an increased applied voltage and an elevated 
temperature in order to obtain a sufficient transfer density. 
Further, there is another problem that when the thermal transfer 
image-receiving material is not kept in close contact with the thermal 
transfer dye-donating material during thermal transfer, part of the 
dye-donating material which is in the form of a thin sheet leaves its 
original position relative to the image-receiving material and produces 
wrinkles. These wrinkles cause streaks in the resulting transferred image, 
i.e., the image has recording unevenness or abnormality. Although 
incorporation of a fluorine-containing compound is effective in preventing 
heat fusion and improves the close-contact property, fluorine-containing 
high-molecular weight compounds which particularly improve the 
close-contact property have poor compatibility with various high-molecular 
weight compounds which are useful as image-receiving material, especially 
with polyester resins. Because of this drawback, there has been the 
problem that with an image-receiving material having a coating of a blend 
of such a fluorine-containing high-molecular weight compound and a 
polyester series resin, the coating suffers phase separation on the 
surface thereof, resulting in formation of minute specks, loss of gloss, 
etc. 
SUMMARY OF THE INVENTION 
An object of the present invention is to provide a thermal transfer 
image-receiving material which is for use in a thermal transfer recording 
and is free of the conventional problems mentioned above. 
Other objects and effects of the present invention will be apparent from 
the following description. 
The above-described problems have been eliminated by a thermal transfer 
image-receiving material comprising a support having thereon an 
image-receiving layer for receiving a dye transferred by heat application 
from a thermal transfer dye-donating material and forming an image, the 
image-receiving layer containing a fluorine-containing high-molecular 
weight compound, a fluorine-containing surfactant, and a matting agent.

DETAILED DESCRIPTION OF THE INVENTION 
Examples of the fluorine-containing high-molecular weight compound employed 
in the present invention include those described in U.S. Pat. Nos. 
4,175,969, 4,087,394, 4,016,125, 3,676,123, 3,679,411, and 4,304,852, 
JP-A-52-129520 (the term "JP-A" as used herein means an "unexamined 
published Japanese patent application"), JP-A-54-158222, JP-A-55-57842, 
JP-A-57-11342, JP-A-57-19735, JP-A-57-179837, "Kagaku Sosetsu (The 
Elements of Chemistry) No. 27, New Fluorine Chemistry" (edited by Nihon 
Kagaku-kai, Japan, 1980), "Functional Fluorine-Containing Polymers" 
(edited by Nikkan Kogyo Shinbun-sha, Japan, 1982), etc. 
These fluorine-containing high-molecular weights compounds may be produced 
according to the methods described in the above-enumerated references. 
Further, they can generally be synthesized by fluorination of the 
corresponding hydrocarbons. A detailed description of fluorination of 
hydrocarbons is given in "Shin Jikken Kagaku Koza (Lectures on New 
Experimental Chemistry)" vol. 14 (I) (Maruzen, Japan, 1977) pp. 308-331. 
The fluorine-containing high-molecular weight compound is incorporated in 
the image-receiving layer of the image-receiving material, together with 
the fluorine-containing surfactant and the matting agent of the present 
invention described hereinafter. The amount of the fluorine-containing 
high-molecular weight compound incorporated in the image-receiving layer 
is in an amount of generally from 0.001 to 3 g/m.sup.2, preferably from 
0.002 to 1.5 g/m.sup.2, more preferably from 0.005 to 1.0 g/m.sup.2, based 
on the surface are of the side of the material. Furthermore, the 
fluorine-containing high-molecular weight compound may be incorporated in 
the other constituent layer(s). 
Specific examples of the fluorine-containing high-molecular weight compound 
are given below, but the fluorine-containing high-molecular weight 
compounds of the present invention are not limited thereto. 
##STR1## 
In the above formulae, m and n each represents an integer of 8 to 1,000. 
These average molecular weights are 1,000 to 60,000. Among them, F-1, F-2, 
F-3, F-4 and F-5 are especially preferred. 
The fluorine-containing surfactant employed in the present invention is a 
surfactant containing a fluorinated hydrocarbon moiety. It may be an 
anionic, cationic, nonionic, and betaine type, or an other type. Nonionic 
types of fluorine-containing surfactants are preferred. Examples of the 
fluorine-containing surfactants are shown below, but the 
fluorine-containing surfactant of the present invention is not limited 
thereto: 
##STR2## 
Among them, Fluorine-containing surfactant A-25, A-27, A-33, A-37, A-38, 
A-39, and A-40 are more preferred. 
Further, examples of the fluorine-containing surfactant further include 
Megafac F-141 to F-144, F-170 to F-173, F-180 to F-184, F-192 to F-195, 
and F-522 manufactured by Dainippon Ink & Chemicals, Incorporated, Japan; 
Surflon S-111 to S-113, S-131 to S-133, S-141, S-101, S-105, S-381, and 
S-382 manufactured by Asahi Glass Co., Ltd., Japan; and Ftergent 400S 
manufactured by NEOS Company Limited, Japan. 
The amount of the fluorine-containing surfactant incorporated in the 
image-receiving layer is preferably from 0.001 to 1 g/m.sup.2, more 
preferably from 0.005 to 0.5 g/m.sup.2. 
The matting agent employed in the present invention is in the form of fine 
particles. It is necessary that the agent not dissolve in the solvent and 
other ingredients of the material or be deformed when the image-receiving 
layer is formed by coating. Examples of the matting agent include the 
compounds shown in JP-A-61-88256, p. 29, such as silicon dioxide, 
polyolefins, and polymethacrylates, and further include the compounds 
shown in JP-A-62-110064 and JP-A-62-110065, such as benzoguanamine resin 
beads, polycarbonate resin beads, and AS resin beads. Fine particles 
comprised of polyethylene, polypropylene or poly(fluorinated carbon) are 
preferred. 
The particle average diameter of the matting agent is generally from 0.01 
to 20 .mu.m, preferably from 0.1 to 10 .mu.m. The amount of the matting 
agent incorporated in the image-receiving layer is preferably from 0.01 to 
1.0 g/m.sup.2, more preferably from 0.05 to 0.5 g/m.sup.2. 
Since the compatibility between the fluorine-containing high-molecular 
weight compound of the present invention and and the high-molecular weight 
compounds of an image-receiving material (for instance a polyester binder) 
is not good, it is desirable that in preparing the coating fluid, the 
fluorine-containing high-molecular weight compound be incorporated 
thereinto in the form of fine dispersion, after being finely divided along 
with the fluorine-containing surfactant and the matting agent by means of 
a dispersing device such as a disperser, homogenizer, mill, or the like, 
so as to be finely dispersed in the coating fluid. 
As the support for use in the thermal transfer image-receiving material of 
the present invention, any support is appropriate provided that it can 
withstand transfer temperatures and satisfy requirements of smoothness, 
whiteness, slip properties, abrasion properties, antistatic properties, 
depression after thermal transfer, etc. Examples of the support include: 
paper supports such as synthetic papers (e.g., polyolefin-based or 
polystyrene-based synthetic papers), wood-free paper, art paper, coat 
paper, cast-coated paper, wall paper, backing paper, papers impregnated 
with synthetic resins or emulsions, papers impregnated with synthetic 
rubber latexes, synthetic resin-internally-added papers, fiber board, 
cellulose fiber paper, and polyolefin-coated papers (particularly, papers 
coated on both sides with polyethylene); films or sheets of various 
plastics such as polyolefins, poly(vinyl chloride), poly(ethylene 
terephthalate), polystyrene, methacrylate plastics, and polycarbonates; 
films or sheets obtained by imparting whiteness and reflecting properties 
to such plastic films or sheets; and laminates comprising any combination 
of layers selected from the above papers and plastic films and sheets. 
The image-receiving layer provided in the thermal transfer image-receiving 
material of the present invention is a coating containing a heat-transfer 
dye-accepting substance (The image-receiving layer is an outermost layer), 
which may be used alone or in combination with other binder substance(s). 
Preferably, the image-receiving layer has a thickness of about from 0.5 to 
50 .mu.m. 
This heat-transfer dye-accepting substance accepts a heat-transfer dye 
transferred in printing from the thermal transfer dye-donating material, 
and is thereby dyed with the heat-transfer dye. Examples of the 
heat-transfer dye-accepting substance include the following resins. 
(A) Ester bond-containing resins 
Polyester resins obtained by the condensation of a dicarboxylic acid such 
as terephthalic acid, isophthalic acid, succinic acid, or the like (these 
dicarboxylic acids may be substituted with a sulfone group, carboxyl 
group, etc.) with ethylene glycol, diethylene glycol, propylene glycol, 
neopentyl glycol, bisphenol A, or the like; polyacrylate or 
polymethacrylate resins such as poly(methyl methacrylate), poly(butyl 
methacrylate), poly(methyl acrylate), and poly(butyl acrylate); 
polycarbonate resins; poly(vinyl acetate) resins; styrene-acrylate resins; 
vinyltoluene-acrylate resins; and the like. Examples of these resins are 
given in JP-A-59-101395, JP-A-63-7971, JP-A-63-7972, JP-A-63-7973, and 
JP-A-60-294862. Further, ester bond-containing resins usable in the 
present invention are commercially available under the trade names of 
Vylon 290, Vylon 200, Vylon 280, Vylon 300, Vylon 103, Vylon GK-140, Vylon 
GK-130 (produced by Toyobo Co., Ltd., Japan), ATR-2009, ATR-2010 (produced 
by Kao Corporation, Japan), and others; 
(B) Urethane bond-containing resins 
Polyurethane resins and the like; 
(C) Amide bond-containing resins 
Polyamide resins and the like; 
(D) Urea bond-containing resins Urea resins and the like; 
(E) Sulfone bond-containing resins 
Polysulfone resins and the like; 
(F) Resins containing other highly polar bonds 
Polycaprolactone resins, styrene-maleic anhydride resins, poly(vinyl 
chloride) resins, polyacrylonitrile resins, and the like. 
In addition to the above-enumerated synthetic resins, mixtures or 
copolymers thereof may also be used. 
Among them, ester bond-containing resins are preferred and polyester 
resins, polyacrylester resins, polycarbonate resins and 
poly(vinylacetate-vinylchloride) copolymer are more preferred. 
A high-boiling point organic solvent or a heat solvent may be incorporated, 
as a heat-transfer dye-acceptable substance or a dye-diffusion aid, in the 
thermal transfer image-receiving material, particularly in the 
image-receiving layer. 
Examples of the high-boiling point organic solvent and heat solvent include 
the compounds mentioned in JP-A-62-174754, JP-A-62-245253, JP-A-61-209444, 
JP-A-61-200538, JP-A-62-8145, JP-A-62-9348, JP-A-62-30247, and 
JP-A-62-136646. 
The image-receiving layer in the thermal transfer image-receiving material 
of the present invention may have a constitution in which the 
heat-transfer dye-acceptable substance is dispersed in a water-soluble 
binder and supported thereby. This water-soluble binder may be any of 
various known water-soluble polymers, but those having a group that can 
undergo a crosslinking reaction with the aid of a film-hardening agent are 
preferred. Of these, gelatin is particularly preferred. 
The image-receiving layer may be comprises two or more layers. In this 
case, it is preferable that the layer situated nearer to the support be 
formed by a synthetic resin having a low glass transition point or by a 
high-boiling point organic solvent or heat solvent so as to have a 
constitution having enhanced dyeability. The outermost layer is preferably 
formed by a synthetic resin having a higher glass transition point or by 
minimum amount of a high-boiling point organic solvent or heat solvent or 
omitting such a solvent. This constitution prevents such troubles as 
surface tackiness, adhesion to other substances, retransfer to other 
substances after thermal transfer, and blocking with a thermal transfer 
dye-donating material. The image-receiving layer present as an outermost 
layer contains the fluorine-containing high-molecular weight compound, the 
fluorine-containing surfactant, and the matting agent in each amount 
aforementioned as being appropriate 
The thickness of the image-receiving layer as a whole is in the range of 
preferably from 0.5 to 50 .mu.m, more preferably from 3 to 30 .mu.m. In 
the case of two-layer constitution, the outermost layer thickness is in 
the range of preferably from 0.1 to 2 .mu.m, more preferably from 0.2 to 1 
.mu.m. 
The thermal transfer image-receiving material of the present invention may 
have an intermediate layer between the support and the image-receiving 
layer. 
According to its composition, the intermediate layer may function as a 
cushioning layer, a porous layer, or a dye diffusion-preventive layer. In 
some cases, the intermediate layer also functions as a dye-fixing agent. 
A dye diffusion-preventive intermediate layer serves, in particular, to 
prevent a heat-transfer dye from diffusing into the support. The binder 
constituting this diffusion-preventive layer may be water-soluble or 
organic solvent-soluble, but a water-soluble binder is preferred. Examples 
thereof include the water-soluble binders mentioned hereinabove with 
respect to the binder for the image-receiving layer. Of these, gelatin is 
especially preferred. 
A porous intermediate layer serves to prevent heat applied for thermal 
transfer from diffusing from the image-receiving layer to the support, 
thereby contributing to effective utilization of applied heat. 
The image-receiving layer, cushioning layer, porous layer, 
diffusion-preventive layer, adhesive layer, etc. which constitute the 
thermal transfer image-receiving material of the present invention may 
contain a fine powder of, for example, silica, clay, talc, diatomaceous 
earth, calcium carbonate, calcium sulfate, barium sulfate, aluminum 
silicate, synthetic zeolite, zinc oxide, lithopone, titanium oxide, 
alumina, or the like. 
A fluorescent brightener may be used in the thermal transfer 
image-receiving material. Examples thereof include the fluorescent 
brightener compounds mentioned in "The Chemistry of Synthetic Dyes" vol. 
5, chapter 8, edited by K. Veenkataraman, and JP-A-61-143752. 
Specifically, examples of the fluorescent brightener include stylbene-type 
compounds, coumarin-type compounds, biphenyl-type compounds, 
benzoxazolyl-type compounds, naphthalimide-type compounds, pyrazoline-type 
compounds, carbostyryl-type compounds, 2,5-dibenzooxazolthiophene-type 
compounds, and the like. 
Such a fluorescent brightener may be used in combination with an 
anti-fading agent. 
There are two types of thermal transfer dye-donating materials which can be 
used together with the image-receiving material of the present invention: 
(1) a thermal transfer dye-donating material comprising a support having 
thereon a layer containing a heat-transfer dye, which is transferred, in 
accordance with the pattern of the applied heat, to the image-receiving 
layer of the thermal transfer image-receiving material to thereby complete 
a recording; and (2) a thermal transfer dye-donating material comprising a 
support having thereon a layer of a heat-fusible ink, which is fused, in 
accordance with the pattern of applied heat, and transferred to the 
thermal transfer image-receiving material to thereby complete a recording. 
The support for the thermal transfer dye-donating material may be any of 
the conventionally known supports. Examples thereof include poly(ethylene 
terephthalate), polyamides, polycarbonates, glassin paper, capacitor 
paper, cellulose esters, fluoropolymers, polyethers, polyacetals, 
polyolefins, polyimides, poly(phenylene sulfide), polypropylene, 
polysulfone, cellophane, and the like. 
The thickness of the support in the thermal transfer dye-donating material 
is generally from 2 to 30 .mu.m. If necessary, an undercoat layer may be 
applied to the support. Further, a dye diffusion-preventive layer 
consisting of a hydrophilic polymer may be provided between the support 
and the dye-donating layer. This serves to further improve transfer 
density. As the hydrophilic polymer, any of the above-enumerated 
water-soluble polymers may be used. 
For the purpose of preventing a thermal head from sticking to the 
dye-donating material, a slipping layer may be provided. This slipping 
layer is composed of a lubricating substance which may or may not contain 
a polymer binder. The lubricating substance, for example, may be a 
surfactant, a solid or liquid lubricant, or a mixture thereof. 
The thermal transfer dye-donating material employing a heat-transfer dye 
basically comprises a support having thereon a thermal transfer layer 
containing a binder and a dye that sublimes or becomes movable upon 
heating. This thermal transfer dye-donating material can be obtained by 
dissolving or dispersing a conventionally known dye that sublimes or 
becomes movable upon heating and a binder resin in a suitable solvent to 
prepare a coating fluid. This coating fluid is applied on one side of a 
support for a conventionally known thermal transfer dye-donating material 
at such a spread rate as to result in a dry coating thickness of, for 
example, about from 0.2 to 5 .mu.m, preferably from 0.4 to 2 .mu.m. The 
applied coating is then dried to form a thermal transfer layer. 
The dye useful in the formation of such a thermal transfer layer includes 
any of those conventionally used for thermal transfer dye-donating 
materials. However, those having molecular weights as low as about 150 to 
800 are particularly preferred in the present invention. In selecting a 
suitable dye, transfer temperature, hue, light fastness, solubility or 
dispersibility in ink and binder resin, etc. are to be taken in account. 
Examples of the dye include disperse dyes, basic dyes, oil-soluble dyes, 
and the like. Particularly preferred are Sumicalon Yellow E4GL, Dianix 
Yellow H2G-FS, Miketone Polyester Yellow 3GSL, Kayaset Yellow 937, 
Sumicalon Red EFBL, Dianix Red ACE, Miketone Polyester Red FB, Kayaset Red 
126, Miketone Fastbrilliant Blue B, Kayaset Blue 136, and the like. In 
addition to these, other known heat-transfer dyes can be used. 
As the binder resin for use with the above dye, any of the binder resins 
conventionally know as binder for this purpose can be used. Normally, a 
resin which has good heat resistance and does not hinder the transfer of 
the dye when heated is selected. Examples of the binder resin include 
polyamide resins, polyester resins, epoxy resins, polyurethane resins, 
polyacrylic resins (e.g., poly(methyl methacrylate), polyacrylamide, and 
poly(styrene-2-acrylonitrile)), vinyl resins including 
polyvinylpyrrolidone, poly(vinyl chloride) resins (e.g., vinyl 
chloride-vinyl acetate copolymers), polycarbonate resins, polystyrene, 
poly(phenylene oxide), cellulose resins (e.g., methyl cellulose, ethyl 
cellulose, carboxymethyl cellulose, cellulose acetate hydrogen phthalate, 
cellulose acetate, cellulose acetate propionate, cellulose acetate 
butyrate, and cellulose triacetate), poly(vinyl alcohol) resins (e.g., 
poly(vinyl alcohol) and partly saponified poly(vinyl alcohol)s such as 
poly(vinyl butyral)), petroleum resins, rosin derivatives, 
coumarone-indene resins, terpene resins, polyolefin resins (e.g., 
polyethylene and polypropylene), and the like. 
It is preferable that such a binder resin be used in an amount of, for 
example, from about 80 to about 600 parts by weight per 100 parts by 
weight of the dye. 
As the ink solvent for dissolving or dispersing the above-described dye and 
binder resin, any of conventionally known ink solvents may be used without 
particular limitation. 
For the purpose of preventing a thermal head from sticking to the 
dye-donating material due to heating when the thermal head is applied to 
the back side of the dye-donating material and thereby enhancing smooth 
movement of the thermal head, it is preferable that the side of the 
support on which a dye-donating layer has not been provided be subjected 
to sticking-preventive treatment. 
For example, a heat-resistant slip layer is preferably applied which 
consists mainly of (i) a product of reaction between a poly(vinyl butyral) 
resin and an isocyanate, (ii) an alkali metal salt or alkaline earth metal 
salt of a phosphoric ester, and (iii) a filler. Preferably, the poly(vinyl 
butyral) resin has a molecular weight of about 60,000 to 200,000 and a 
glass transition temperature of 80.degree. to 110.degree. C. Further, from 
the standpoint of increasing the number of reaction sites that take part 
in the reaction with the isocyanate, the resin preferably is one in which 
the content of the vinyl butyral moieties is from 15 to 40% by weight. As 
the alkali metal salt or alkaline earth metal salt of a phosphoric ester, 
Gafac RD720 produced by Toho Chemical Industry Co., Ltd., Japan or the 
like is used generally in an amount of about from 1 to 50% by weight, 
preferably about from 10 to 40% by weight, based on the amount of the 
poly(vinyl butyral) resin. 
It is desirable that the lower layer of the heat-resistant slip layer 
possess heat resistance. This may be attained by applying to the lower 
layer a coating consisting of a combination of a thermoset synthetic resin 
and a hardener therefor, for example, a combination of poly(vinyl butyral) 
and a polyisocyanate, a combination of an acrylic polyol and a 
polyisocyanate, a combination of cellulose acetate and a titanium 
chelating agent, or a combination of a polyester and an organotitanium 
compound. 
According to need, a hydrophilic barrier layer may be provided in the 
dye-donating material in order to prevent diffusion of the dye toward the 
support. This hydrophilic dye-barrier layer contains a hydrophilic 
substance useful for the intended purpose. In general, good results are 
obtained by use of gelatin, polyacrylamide, poly(isopropylacrylamide), 
butyl methacrylate-grafted gelatin, ethyl methacrylate-grafted gelatin, 
cellulose monoacetate, methyl cellulose, poly(vinyl alcohol), 
poly(ethylene imine), poly(acrylic acid), a mixture of poly(vinyl alcohol) 
and poly(vinyl acetate), a mixture of poly(vinyl alcohol) and poly(acrylic 
acid), or a mixture of cellulose monoacetate and poly(acrylic acid). 
Particularly preferred of these are poly(acrylic acid), cellulose 
monoacetate, and poly(vinyl alcohol). 
An undercoat layer may be provided in the dye-donating material. This 
undercoat layer may have any constitution as long as the dye-donating 
material produces the desired effects when used along with the 
image-receiving material of the present invention. Preferred examples of 
the material for the undercoat layer include an acrylonitrile-vinylidene 
chloride-acrylic acid copolymer (14:80:6 by weight); a butyl 
acrylate-2-aminoethyl methacrylate-2-hydroxyethyl methacrylate copolymer 
(30:20:50 by weight); linear saturated polyesters, e.g., Bostic 7650 
(Emhurt Company, Bostic Chemical Group); and chlorinated high-density 
poly(ethylene-trichloroethylene) resins. The amount of the undercoat layer 
applied is not particularly limited, but is normally from 0.1 to 2.0 
g/m.sup.2. 
In the second embodiment of the thermal transfer dye-donating material for 
use in conjunction with the present invention, the thermal transfer layer 
is a heat-fusible transfer layer formed from a thermal transfer 
layer-forming ink comprising a wax which contains a colorant such as a dye 
or a pigment. This ink is prepared by incorporating and dispersing a 
colorant selected from carbon black and various dyes and pigments into a 
wax. The wax functions as a binder, having a proper melting point, for 
example, a paraffin wax, microcrystalline wax, carnauba wax, or urethane 
wax. The proportion of the colorant to wax used is preferably in such a 
range that the colorant comprises about from 10 to 65% by weight of the 
resulting heat-fusible transfer layer. The preferred range of the 
thickness of the transfer layer formed is about from 1.5 to 6.0 .mu.m. 
Preparation of the ink and application thereof on a support may be 
conducted according to known techniques. 
In forming the dye-donating layer, dyes are suitably selected so as to 
produce a desired hue through transfer printing. If necessary, two or more 
dye-donating layers containing different dyes may be arranged side by side 
in a single thermal transfer dye-donating material. For example, in the 
case where an image like a color photograph is to be formed by repeated 
printing of each color according to color-separation signals, it is 
desirable that the printing produce a cyan, magenta, and yellow color and 
thus three dye-donating layers containing dyes providing such hues be 
arranged side by side. Alternatively, a dye-donating layer containing a 
dye giving a black hue may be provided in addition to the dye-donating 
layers providing cyan, magenta, and yellow hues. It is preferable that 
when these dye-donating layers are formed, a marking for a location search 
be provided simultaneously, since this eliminates the necessity of an 
ink-printing step which must be conducted separately from the dye-donating 
layer formation. 
For the purpose of improving releasability between the thermal transfer 
dye-donating material and the thermal transfer image-receiving material of 
the present invention, it is preferable to incorporate a release agent in 
the layers constituting the dye-donating material and/or the 
image-receiving material, particularly preferably in that outermost layer 
of each material at which the materials come to contact with each other. 
Any of conventionally known release agents can be used. Examples thereof 
include solid release agents or wax-like substances such as polyethylene 
wax, amide wax, silicone resin fine powder, and fluoroplastic fine powder; 
surfactants of the fluorine-containing type, phosphate type, or other 
types; oils of the paraffin type, silicone-type, or fluorine-containing 
type; and the like. Of these, a silicone oil is particularly preferred. 
The silicone oil may be unmodified or modified such as a carboxy-modified, 
amino-modified, epoxy-modified, polyether-modified or alkyl-modified 
silicone oil. These silicone oils may be used alone or in combination of 
two or more thereof Examples of such silicone oils include the various 
modified silicone oils described in "Modified Silicone Oils" pp. 6-18B, 
issued from Shin-Etsu Silicone Co., Ltd., Japan. For use in an organic 
solvent-based binder, an amino-modified silicone oil is effective which 
has a group that is reactive to a crosslinking agent for the binder (e.g., 
a group reactive to an isocyanate). On the other hand, a carboxy-modified 
silicone oil (e.g., trade name X-22-3710, manufactured by Shin-Etsu 
Silicone Co., Ltd.) or an epoxy-modified silicone oil (e.g., trade name 
KF-100T, manufactured by Shin-Etsu Silicone Co., Ltd.) is effective if the 
silicone oil is dispersed and emulsified in a water-soluble binder. 
Each of the layers constituting the thermal transfer image-receiving 
material of the present invention and constituting the thermal transfer 
dye-donating material to be used with the image-receiving material may 
have been cured by a film-hardening agent. 
In the case of curing organic solvent-based polymers, the film-hardening 
agents described in JP-A-61-199997, JP-A-58-215398, etc. can be used. 
Isocyanate-type film-hardening agents are particularly preferred for 
polyester resins. 
To cure water-soluble polymers, the film-hardening agents described in U.S. 
Pat. No. 4,678,739, column 41, JP-A-59-116655, JP-A-62-245261, 
JP-A-61-18942, etc. are preferable. Examples of such hardeners include 
aldehyde-type film-hardening agents (e.g., formaldehyde), aziridine-type 
film-hardening agents, epoxy-type film-hardening agents (e.g., 
##STR3## 
vinylsulfone-type film-hardening agents (e.g., 
N,N'-ethylenebis(vinylsulfonylacetamido)ethane), N-methylol-type 
film-hardening agents (e.g., dimethylolurea), and high-molecular 
film-hardening agents (e.g., the compounds given in JP-A-62-234157). 
An anti-fading agent may be used in the thermal transfer dye-donating 
material or the thermal transfer image-receiving material. Examples of the 
anti-fading agent, include an antioxidant, an ultraviolet absorber, or a 
metal complex of a certain kind. 
Exemplary antioxidants include chroman-type compounds, coumaran-type 
compounds, phenol-type compounds (e.g., hindered phenols), hydroquinone 
derivatives, hindered amine derivatives, and spiroindane-type compounds. 
In addition, the compounds shown in JP-A-61-159644 are also effective. 
Exemplary ultraviolet absorbers include benzotriazole-type compounds (U.S. 
Pat. No. 3,533,794 etc.), 4-thiazolidone-type compounds (U.S. Pat. No. 
3,352,681 etc.), benzophenone-type compounds (JP-A-56-2784 etc.), and the 
compounds shown in JP-A-54-48535, JP-A-62-136641, JP-A-61-88256, etc. In 
addition, the ultraviolet- absorbing polymers described in JP-A-62-260152 
are also effective. 
Exemplary metal complexes include the compounds shown in U.S. Pat. No. 
4,241,155, U.S. Pat. No. 4,245,018, columns 3-36, U.S. Pat. No. 4,254,195, 
columns 3-8, JP-A-62-174741, JP-A-61-88256, pp. 27-29, JP-A-1-75568, 
JP-A-63-199248, and Japanese Patent Application No. 62-230596, etc. 
Examples of useful anti-fading agents are given in JP-A-62-215272, pp. 
125-137. 
The anti-fading agent for preventing the fading of the dye transferred to 
the image-receiving material may have been incorporated beforehand in the 
image-receiving material, or it may be fed to the image-receiving material 
by, for example, transferring the anti-fading agent from the dye-donating 
material. 
The above-described antioxidant, ultraviolet absorber, and metal complex 
may be used in combination of two or more thereof. 
Various surfactants may be used for the constitutional layers of the 
thermal transfer dye-donating material and the thermal transfer 
image-receiving material, to improve coating properties, releasability, 
slip properties, or antistatic properties or to accelerate development, or 
for other purposes. 
Nonionic surfactants, anionic surfactants, ampholytic surfactants, and 
cationic surfactants may be used. Specific examples thereof are shown in 
JP-A-62-173463, JP-A-62-183457, etc. 
Further, use of a surfactant as a dispersing agent is preferred when a 
heat-transfer dye-accepting substance, release agent, anti-fading agent, 
ultraviolet absorber, fluorescent brightener, and other hydrophobic 
compounds are dispersed in a water-soluble binder. In addition to the 
above surfactants, those shown in JP-A-59-157636, pp. 37-38 are 
particularly preferable for this purpose. 
An organofluorine compound may be incorporated in the constituent layers of 
the thermal transfer dye-donating material or the thermal transfer 
image-receiving material to improve slip properties, antistatic 
properties, releasability, etc. Representative examples of the 
organofluorine compound include the fluorine-containing surfactants given 
in JP-B-57-9053, columns 8-17 (the term "JP-B" as used herein means an 
"examined Japanese patent publication"), JP-A-61-20944, JP-A-62-135826, 
etc., fluorine-containing oily compounds such as fluorine-containing oils, 
and fine powders of fluoroplastics such as polytetrafluoroethylene resins. 
Incorporation of a silicone oil containing a polyether group is also 
effective for the above purpose. Further, the combination of a 
polyether-modified silicone oil and a fluoroplastic fine powder is also 
effective. 
By use of the thermal transfer image-receiving material of the present 
invention in combination with the above-described thermal transfer 
dye-donating material, a printed color image with good gradation can be 
obtained, which also has excellent clarity and resolution. That is, the 
dye-donating material is superposed on the image-receiving material, and 
heat energy according to image information is applied from either side of 
the superposed materials, preferably from the back side of the 
dye-donating material, by a heating means such as, for example, a thermal 
head, thereby transferring the dye from the dye-donating layer to the 
image-receiving material in accordance with the magnitude of the applied 
heat energy, to print a color image with good gradation and excellent 
clarity and resolution. 
The heating means is not limited to thermal head, and other know heating 
means can be used, such as a laser light (e.g., semiconductor laser), an 
infrared flash, a hot pen, and the like. 
In combination with a thermal transfer dye-donating material, the thermal 
transfer image-receiving material of the present invention can be utilized 
in various printers of the thermal printing type; facsimile; image 
printing by means of a magnetic, optomagnetic, or optical recording 
technique or the like; image printing from television or CRT pictures; or 
in other applications. 
With respect to details of thermal transfer recording techniques, reference 
may be made to the related description in JP-A-60-34895. 
As described above, the present invention is an excellent thermal transfer 
image-receiving material to which a thermal transfer dye-donating material 
does not heat-fuse during thermal transfer printing, and which is good in 
the property of maintaining close contact with the dye-donating material 
during thermal transfer printing. Hence, the image-receiving material 
never causes any abnormality such as streaks or specks in the resulting 
printed image. 
The present invention is explained below in more detail with reference to 
the following Example and Comparative Example, but the Example should not 
be construed as limiting the scope of the invention. 
EXAMPLE AND COMATIVE EXAMPLE 
Preparation of thermal transfer image-receiving materials and thermal 
transfer dye-donating materials, printing by use of both materials, and 
examination of the thermal transfer image-receiving materials were 
conducted as follows. 
Preparation of Thermal Transfer Dye-Donating Material 
As a support, a 6 .mu.m-thick polyester film (manufactured by Teijin 
Limited, Japan) was used which had been coated on one side with a 
heat-resistant slip layer formed from a thermosetting acrylic resin. This 
support was coated, side by side on the side opposite to the 
heat-resistant slip layer side, with each dye-donating layer-forming ink 
composition consisting of the following ingredients at a spread rate of 
1.2 g/m.sup.2 on a dry basis, thereby obtaining a dye-donating material. 
______________________________________ 
Cyan ink composition for forming dye-donating layer: 
Dye-a 3 parts 
Poly(vinyl butyral) resin 2.5 parts 
(Denkabutyral 5000A, manufactured by Denki 
Kagaku Kogyo K.K., Japan) 
Polyisocyanate 0.1 part 
(Takenate D110N, manufactured by Takeda 
Chemical Industries, Ltd., Japan) 
Amino-modified silicone oil 
0.004 part 
(KF-857, manufactured by Shin-Etsu Chemical 
Industries Co., Ltd., Japan) 
Methyl ethyl ketone 50 parts 
Toluene 50 parts 
Dye-a: 
##STR4## 
Magenta ink composition for forming dye-donating layer: 
Dye-b 2.5 parts 
Poly(vinyl butyral) resin 2.5 parts 
(S-Lecs BX-1, manufactured by Sekisui 
Chemical Co., Ltd., Japan) 
Polyisocyanate 0.1 part 
(KP-90, manufactured by Dainippon Ink & 
Chemicals, Incorporated, Japan) 
Silicone Oil 0.004 part 
(KF-857, manufactured by Shin-Etsu 
Chemcial Industries Co., Ltd.) 
Methyl ethyl ketone 70 parts 
Toluene 30 parts 
Dye-b: 
##STR5## 
Yellow ink composition for forming dye-donating layer: 
Dye-C 5 parts 
Ethyl cellulose 3 parts 
Methyl ethyl ketone 50 parts 
Toluene 50 parts 
Dye-c: 
##STR6## 
______________________________________ 
Preparation of Thermal Transfer Image-Receiving Material 
Low-density polyethylene which had a thickness of 33 .mu.m and into which 
titanium oxide and ultramarine had been kneaded was laminated to one side 
of a 175 .mu.m-thick wood-free paper support. On the other side of the 
support, 32 .mu.m-thick high-density polyethylene was laminated. Then, the 
resulting polyethylene-coated paper was coated, on the low-density 
polyethylene-laminated side, with a hydrophilic binder layer-forming 
composition (1) specified below at a spread rate of 1 g/m.sup.2 in terms 
of gelatin amount. 
______________________________________ 
Composition (1) for forming hydrophilic binder layer: 
______________________________________ 
Gelatin 60 g 
Water 3,000 g 
Surfactant 2.3 g 
##STR7## 
Thickening agent 1.4 g 
(potassium salt of 
poly(styrene sulfonic acid)) 
______________________________________ 
On this hydrophilic binder layer, an image-receiving layer-forming Coating 
Composition (2) consisting of the ingredients shown below was applied by 
Gieser coating at a spread rate of 10 g/m.sup.2 based on the surface area 
of the polyester. Thus, thermal transfer image-receiving materials (1) to 
(6) were prepared. The applied coating composition was air-dried in a 
draft and then dried in an oven at 100.degree. C. for 30 minutes. 
Coating composition (2) for forming image-receiving layer was prepared by 
dispersing the following ingredients in homogenizer at 1000 rpm for 5 
minutes. 
______________________________________ 
Coating composition (2) for forming image-receiving layer: 
______________________________________ 
Polyester resin 20 g 
Isocyanate-type hardener 
3 g 
(KP-90, manufactured by Dainippon Ink & 
Chemicals, Incorporated) 
Amino-modified silicone oil 
0.5 g 
(KF-857, manufactured by Shin-Etsu Chemical 
Industries Co., Ltd.) 
Fluorine-containing high-molecular 
shown in Table 1 
weight compound 
Fluorine-containing surfactant 
shown in Table 1 
Matting agent shown in Table 1 
Methyl ethyl ketone 100 ml 
Toluene 100 ml 
______________________________________ 
Composition of polyester resin (mol %): 
##STR8## 
- 
Molecular weight; about 20,000 
TPA = terephthalic acid 
IPA = isophthalic acid 
SIPA =- 
##STR9## 
BIS-A-ED =- 
##STR10## 
EG = ethylene glycol 
The thus-obtained thermal transfer dye-donating material and thermal 
transfer image-receiving material were superposed on each other in such a 
manner that the thermal transfer layer was in contact with the 
image-receiving layer. A thermal head was applied thereto from the support 
side of the thermal transfer dye-donating material under conditions of 
thermal head output 0.25 W/dot, pulse length 0.2-15 msec, and dot density 
6 dots/mm. Thus, thermal transfer was conducted in the order of yellow, 
magenta, and cyan at the same place to obtain a black print. 
For evaluation of heat fusion, a black print was formed at a pulse length 
of 15 msec, and evaluation was made in 5 grades according to the frequency 
of fusion occurrence. 
1: 0/10 to 1/10 
2: 2/10 to 3/10 
3: 4/10 to 6/10 
4: 7/10 to 8/10 
5: 9/10 to 10/10 
Grade 1 means presence of 0 to 1 sheets with fusion per 10 sheets of black 
prints obtained by the thermal transfers. 
For evaluation of the print surface for the presence or absence of 
abnormality, a gray print was formed at a pulse length of 8 msec and an 
emission density of about 1.2. Print surface abnormality was evaluated in 
5 grades according to the frequency of abnormality occurrence, using the 
same criteria as in the fusion evaluation. 
TABLE 1 
__________________________________________________________________________ 
Fluorine-contain- 
ing high-molecular 
Fluorine-contain- 
weight compound 
ing surfactant 
Matting agent Print surface 
Amount Amount Amount abnormality 
Print 
Sample No. (g/m.sup.2) 
(g/m.sup.2) (g/m.sup.2) 
Fusion 
Streak 
Speck 
surface 
__________________________________________________________________________ 
1 (Comparison) 
none 0 none 
0 spherical polyethylene 
0.1 5 5 1 glossy 
beads 
2 (Comparison) 
F-1 0.05 none 
0 spherical polyethylene 
0.1 1 1 5 with minute 
beads specks 
3 (Comparison) 
none 0 A-25 
0.05 spherical polyethylene 
0.1 2 4 1 glossy 
beads 
4 (Invention) 
F-1 0.05 " 0.05 spherical polyethylene 
0.1 1 1 1 " 
beads 
5 (Invention) 
F-2 0.05 " 0.05 spherical polyethylene 
0.1 1 1 1 " 
beads 
6 (Invention) 
F-3 0.05 " 0.05 spherical polyethylene 
0.1 1 1 1 " 
beads 
7 (Invention) 
F-1 0.05 A-38 
0.05 spherical polyethylene 
0.1 1 1 1 " 
beads 
8 (Invention) 
F-1 0.05 A-39 
0.05 spherical polypropylene 
0.1 1 1 2 " 
beads 
9 (Invention) 
F-1 0.10 " 0.10 spherical polyethylene 
0.1 1 1 1 " 
beads 
10 (Invention) 
F-1 0.02 " 0.05 spherical polyethylene 
0.1 1 2 1 " 
beads 
11 (Invention) 
F-1 0.02 " 0.05 spherical polyethylene 
0.2 1 1 1 " 
beads 
12 (Invention) 
F-4 0.05 A-38 
0.05 spherical polyethylene 
0.1 1 1 1 " 
beads 
13 (Invention) 
F-5 0.05 " 0.05 spherical polyethylene 
0.1 1 1 1 " 
beads 
14 (Invention) 
F-6 0.05 A-39 
0.05 spherical polyethylene 
0.1 2 1 2 " 
beads 
15 (Invention) 
F-7 0.05 " 0.05 spherical polyethylene 
0.1 2 1 1 " 
beads 
__________________________________________________________________________ 
While the invention has been described in detail and with reference to 
specific embodiments thereof, it will be apparent to one skilled in the 
art that various changes and modifications can be made therein without 
departing from the spirit and scope thereof.