JPH0717141A - Thermal transfer printing medium - Google Patents

Abstract

PURPOSE: To obtain a color reproduced product with modified resolution and image quality by providing plural heat-sensitive inks having the same color but a varying saturation level in the plural coating regions of a base sheet. CONSTITUTION: A ribbon 30 has a first yellow panel 34Y1 and a second yellow panel 34Y2 which are of a varying density level of a coloring material, and the ink layer of the panel 34Y1 is a completely saturated ink layer and the ink layer of the panel 34Y2 is an ink layer with a low degree of saturation such that the reflective density of ink is 50% of the completely saturated layer ink after the transfer of the ink layer to a recording medium. Similarly the repeating group of panels comprises a first and a second magenta panel 34M1 , 34M2 and a first and a second cyan panel 34C1 , 34C2 . The ink layers of these pairs show a deteriorated degree of complete saturation, for example, the degree of saturation being 50%. This ribbon 30 can print in a wider range of colors or color brightness without dithering.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates generally to thermal transfer print media, and more particularly to a new thermal (wax) transfer print media, or thermal transfer print ribbon, for printing multicolor (color) or multiple brightness level images. Regarding

[0002]

2. Description of the Related Art Various thermal transfer printing techniques, that is, recording techniques are known. The basic process, commonly known as hot wax transfer printing, involves contacting a recording medium with a layer of hot melt ink on a thin ribbon-like support. A selected area of the ink layer is heated through the support to melt the ink in this area. Then, the support is removed and the melted ink is transferred to the recording medium.

[0003] Typically, a thermal printout having an array of individually controlled resistive heating elements in performing this process.
The head heats the ribbon. An associated control circuit energizes the selected heating element to melt the tod size area of the ink layer, which is the ribbon, and the recording medium passes through the print head. Next, the recording medium and the ribbon are separated, and the dots of the melted ink are transferred to the recording medium.

In a relatively inexpensive thermal wax transfer printer, the print head and ribbon are mounted on a reciprocating carriage. The carriage repeatedly passes through the recording medium, writing one or more rows of dots in each pass. After each print cycle, a pinch roll, grit wheel, etc., advance the recording medium by the width of the ribbon. The ribbon used in this type of system may be a single color (eg, black) ink, or
Repeated stripes of different colors (eg cyan, magenta and yellow) to allow multicolor printing, ie
It may be a band. With a single color ribbon, the print cycle passes through the recording medium once. However, with multicolor printing, each print cycle requires multiple passes, one pass for each color of ribbon ink.

Other prints include the Phaser II PXi type sold by Tektronix of Oregon, USA and
There is a Phaser II PXe type (Phaser is a registered trademark of Tektronix) color printer, which uses a thermal wax transfer ribbon having a width approximately equal to the width of the recording medium to be printed. Ink extended substantially the width of the ribbon, as disclosed in US Pat. No. 4,530,095 to Seto et al.
The film is of a single color, usually black, or is formed in the form of a repeating series of bands or panels of different colors. The ribbon and recording medium (paper sheet or overhead transparent film) are drawn by a nip between the elongated stationary print head and the opposite pressure roll or platen, and the selected dot of ribbon is
The size area is heated by the print head. To form a full color image, the recording sheet is passed through the nip 3-4 times, each time a different color panel contacts the recording medium. A variety of mechanical mechanisms can be used to move the recording sheet back and forth across a print head including a drum, platen or capstan drive system.

The thermal transfer ribbon disclosed in the above-mentioned Seto et al. Patent comprises a continuous elongated carrier that carries a plurality of equal-sized regions or panels of transparent hot-melt ink. The panels are arranged in a fixed repeating sequence. This sequence includes one panel for each of the primary colors in the subtractive mix, cyan, magenta, and yellow (CMY). Also, in this order,
It may include a panel of black (K) ink. This ribbon is used to continuously transfer different primary color (and black) patterns onto a recording medium to form a full color image. Printers using such ribbons can reproduce red, green and blue by superimposing two subtractive primary color points. Therefore, for example, red is formed by superimposing dots of yellow and magenta ink, green is formed by superimposing yellow and cyan, and blue is formed by superimposing cyan and magenta. 3 if the ribbon does not include a black ink panel in forming the black image area, or if the "processed black" is preferable to the color produced using the black ink panel. Reproduce the black area by overlaying all the primary colors.

Most thermal wax transfer printers, such as the Phaser II series described above, print a single color dot of a given size. These printers use a ribbon of the type disclosed in the above-mentioned Seto et al. Patent to produce seven solid fill colors (uniformly filled color:
Only cyan, magenta, yellow, red, green, blue and black) can be generated. Other hues and these 7 bright tones (unsaturated tones) can be generated by dithering.

In the dithering process, the image is dithered.
Disassemble into cells. Note that each of these dither cells creates a matrix of dots. The number of dots in the dither cell will vary depending on the maximum resolution of the printer and other factors known to those skilled in the art. For example, a typical thermal wax transfer printer has a resolution of up to 300 dots / inch (11.8 dots / mm) depending on the size and gap of the heating elements in its print head. However, this printer can achieve its resolution by limiting its gamut to only seven directly printable colors and white.
To print a wide range of colors by dithering, a dither cell consisting of 16 dots arranged in a 4 × 4 rectangular matrix is used instead. With such a matrix, the printer can vary the number of primary color dots printed in each cell to allow each primary color (when using CMYK ribbons) to be at 16 different brightness levels.
Black also) can be played. "White", which is the color of the recording sheet,
This is the result of not printing color dots in the dither cell matrix.

Other colored shades are also reproduced by printing by overlaying the dither cell matrix patterns of the three primary colors (and black). The human eye perceives the mixed result of the primary color dots of subtractive mixing and white (dot positions not printed) as a single color. The number of colors that can be generated by dithering is, of course, determined by the number of dot positions in the dither cell matrix. In the 4 × 4 matrix, a total of 4096 colors are possible by printing each of the 16 dot positions with any of the three primary colors or leaving it without the printer (white). Size 8
A printer using x8 cells is theoretically 2621
It can reproduce 44 different colors.

The prior art will be further described with reference to the accompanying drawings. 5 is a plan view of a conventional thermal wax transfer ribbon, and FIG. 6 is a longitudinal sectional view taken along line II-II of FIG. The above Tektronix Phaser II
A conventional thermal wax transfer ribbon 10 of the type used by series printers is a transparent, heat resistant plastic film having a width W approximately equal to the width (or length) of the recording medium on which it is printed. , A continuous strip or base 12 in the lengthwise direction. The ends of the film strip are tubular cores 14, 16
Is wound around the supply roll 18 and the take-up roll 20.
To form. This film strip consists of a yellow panel 22Y, a magenta panel 22M and a cyan panel 22.
In a panel including C and a black panel 22K, ie a repeating combination A of swaths, carrying many non-overlapping ink layers 22 of different colors arranged side by side (or end to end). Alternatively, the ribbon may be formed by a repeating combination of only yellow, magenta and cyan panels (ie, without a separate black ink panel).

Substantially expanding the length of the film strip 12 along one end reveals a narrow timing strip 24 having single and double timing marks 26, 28. This timing strip is a black or opaque coating layer with transparent or white timing marks in between,
This coating layer is used to determine the exact location of the ribbon during the printing process. So, for example,
Double timing marks are shown on the first panel (2
2Y) and the single timing mark indicates the start of each of the remaining panels (22M, 22C, 22K) of this combination. With other timing marks,
It may indicate the start or end of the ribbon.

A typical thermal wax transfer ribbon of the type shown in FIGS. 5 and 6 has an overall width of 224 mm,
The width of the ink layer 22 is 214.5 mm. Base 12
Is a strip of polyester film having a thickness of 5.5 μm and baking length of 330 meters. Such a strip can print 275 pages with a 4-color (CMYK) ribbon and 365 pages with a 3-color (CMY) ribbon.

[0013]

The obvious problem with dithering in the prior art as described above is that the effective output resolution of the printer is reduced. For example, 300d
Utilizing a 4x4 dot dither cell in a pi (dots per inch) printer reduces the effective output resolution of the printer to 75 dpi. Also, 8 × 8
By using dot cells, the effective output resolution of the printer is reduced to 37.5 dpi. This loss of resolution is most noticeable when printing colored diagonals.
Another problem is that when the color of the recording medium is not white in the middle, the color of the recording medium adversely affects the color generated by dithering. If there is too much white space in each dither cell, colors with low saturation levels will be the most affected.
Further, when the color of the recording medium is unknown or cannot be controlled, it is difficult to accurately reproduce the desired color by dither.

Accordingly, it is an object of the present invention to provide a thermal transfer print medium that overcomes or reduces the above problems.

[0015]

A general feature of the thermal transfer printer media of the present invention is the ability to reproduce a wide range of colors or color intensity levels. Also, a limiting feature of the thermal wax transfer printer media of the present invention is that they have ink coatings of the same hue at different levels of saturation. Further, a related feature of the thermal wax transfer printer media of the present invention is that they have ink coatings of the same hue at different levels of colorant concentration.
Another feature of the thermal transfer medium of the present invention is that it has many ink coatings of primary hues and secondary hues corresponding to a mixture of these primary hues. Another feature of the thermal transfer media of the present invention is that it also has many subtractive mixed primary hues and ink coatings of other colors.
Further, a feature of the improved thermal transfer media of the present invention is that it is capable of providing a color reproduction of improved resolution and image quality intended for use in a color printer system.

The above and other features and advantages of the present invention provide a thermal transfer medium or ribbon comprising a base sheet and a plurality of different thermal transfer inks applied to the base sheet in a plurality of coating areas. Can be achieved by According to one aspect of the invention, the ribbon has many ink coatings of the same hue at different colorant concentration (saturation) levels. Also in accordance with another aspect of the invention, the ribbon has many primary hues (eg, cyan, magenta, and yellow) and secondary hues (eg, blue, red, and red) corresponding to a mixture of these primary hues. Ink coating with green). Further, in another aspect of the invention, a ribbon has an ink coating of a subtractive mix primary hue and one or more coatings of a particular color, together with a uniform spot color, as well as the primary and / or spot colors. It is possible to print possible colors by superposing and dithering the colors. The above and other aspects of the present invention will be apparent from the following detailed description with reference to the accompanying drawings.

[0017]

1 is a cross-sectional plan view of a thermal transfer ribbon according to an embodiment of the present invention. The thermal transfer ribbon 30 according to this embodiment is similar in construction to the prior art ribbon 10 described above, but with multiple ink coating layers of the same hue at multiple colorant saturation levels. Thus, by way of example, the ribbon 30 may be a repeating set B of panels.
In FIG. 3, there are many non-overlapping ink layers 34 of different hues arranged side by side (or in a vertical row). Although the ink layers are illustrated as a series of contiguous panels, in practice the films are usually separated by small gaps, as shown in FIG. Series B preferably has a first yellow panel 34Y1 and a second yellow panel 34Y2 at different colorant concentration levels. For example, the ink layer of panel 34Y1 is a “fully saturated” ink layer equivalent to the ink layer of panel 22Y (FIG. 5). The ink layer of the panel 34Y2 has an ink reflection density of 50% of the fully saturated layer ink after being transferred to a recording medium.
The ink layer has a low degree of saturation. Similarly, the series B is
It comprises first and second magenta panels 34M1, 34M2 and first and second cyan panels 34C1, 34C2, the ink layers of each pair having either full or reduced saturation (eg 50%). It is an ink layer.

In accordance with the present invention, such ribbons may include many panels 34 of the same hue. In this case, each prints at a different saturation or colorant concentration level and an increased reflection density value. Therefore, ribbon 3
A 0 can print 18 different uniform colors directly (ie, without dithering). In this case, the colors resulting from the superimposed hues of the same hue are not included, but the colors resulting from the different saturation levels, eg, the dots superimposed from panels 34Y1 and 34Y2, or the dots superimposed from three different panels. Including. Due to the contrast, conventional ribbons such as ribbon 10 can print only 6 colors (plus black) directly. A ribbon with a panel 34, which is a tri-primary pair of primary colors corresponding to 67% / 33% colorant concentration levels instead of 100% / 50%, has 21 different uniform colors containing the same hue combination. ,
One can print 36 uniform colors by superimposing dots from three different panels. Obviously, ribbons with more than two panels of each primary color at different colorant concentration levels have a wider range of uniform colors available. A particularly preferred form of ribbon having many panels of the same color at different colorant concentration levels is such that the odd image areas printed by these panels have evenly spaced CIE L * (brightness) values.
The colorant concentration level is selected.

Another type of ribbon is an ink layer 34.
May further include a black ink panel (not shown) at multiple colorant concentration levels. Such ribbons can print black directly at two optical density levels (B1 and B2) or at three optical density levels (B1, B2 and B1 + B2).

FIG. 2 shows a thermal transfer ribbon 40 according to a second embodiment of the present invention. The ribbon 40 is also generally similar in construction to the ribbon 10 (FIG. 5) described above, except that the primary colors of the subtractive mix (cyan, magenta, and yellow) and the secondary hues corresponding to the mix of these primary hues. Ink layer 44 is included. Therefore, the ribbon 40 has a series of repeated sets C
42 with many non-overlapping ink layers 44 of different hues arranged side by side (or in tandem) in
It is equipped with Series C includes green panel 44G, yellow panel 44Y, red panel 44R, magenta panel 44M, blue panel 44B and cyan panel 44C. Optionally, ribbon 40 may include a black panel 44K (not shown). Ribbon 40
Can print directly on a single layer an image containing any of the subtractive primary colors (CMY) and / or the secondary colors (RGB) corresponding to the mixture of these primary colors. Such a single layer print avoids the problem of color purity due to misalignment of overlapping primary color dots. If desired, an additional 9 uniform colors can be obtained by a combination of superposition of primary and secondary hues. This can extend the available color range of a uniformly full image from six colors (using a conventional three color ribbon) to fifteen colors using the ribbon 40. As can be appreciated, this embodiment of the invention is applicable to both thermal wax transfer and dye diffusion or dye sublimation thermal transfer media.

In some circumstances, it may be particularly desirable or necessary to directly reproduce a particular color rather than dithering the subtractive mix primaries. Examples of this are certain uniform color reproductions, shadows that form part of the company logo, or colors that are difficult to reproduce accurately by dithering, such as "skin tone" tones. This requirement is the third requirement of the present invention shown in FIG.
Filled by example. The thermal transfer ribbon 50 comprises a film base 5 having a number of non-overlapping ink layers 54 of different hues arranged in a repeating series D.
It has 2. This series D is a yellow panel 54.
In addition to the Y, magenta panel 54M, cyan panel 54C and (optional) black panel 54K, a panel 54S of any desired special or temporary color is included. The ribbon 50 may also include additional temporary color panels in a repeating series D. The colorants of the ink layer forming the panel 54S are the panels 54Y, 54M and 5
It may be composed of a specific combination of yellow, magenta and cyan colorants used in the 4C ink layer. The colorant of this ink layer may also be composed of other different colorants including colors outside the color range obtainable by mixing the yellow, magenta and cyan colorants of the panels 54Y, 54M and 54C. Good. This embodiment of the invention is applicable to both thermal wax transfer and dye diffusion (dye sublimation) type ribbons.

FIG. 4 shows a fourth embodiment of the present invention. Ribbon 60 contains many ink coatings of the same color at different colorant concentration (saturation) levels to allow enhanced grayscale (halftone) printing. Ribbon 60 includes a film base 62 having a number of non-overlapping ink layers 64 of a single hue, preferably black. Layers 64 are arranged in a repeating series of sets E, and panels 64K1, 64K2, 6 of different colorant concentrations are used.
Includes 4K3 and 64K4. Thus, printing uniform image areas of different optical density. The colorant concentration of layer 64 is chosen appropriately to obtain a wide range of optical densities in the printed image. For example, panels 64K1 to 64
The K4 colorant concentration is selected to obtain uniform image areas on white paper with optical densities of 1.6, 0.8, 0.4 and 0.2, respectively. With this type of ribbon on a suitable printer, 11-step halftones (10 steps in black and gray and white) can be printed directly. As you can see, using one panel 64K, the optical density is 1.6, 0.8,
Print 0.4 and 0.2 uniform image areas. Also, the areas (dots) of two different panels are overlaid to print image areas with optical densities of 2.0, 1.8, 1.2, 1.0 and 0.6. Only image areas with an optical density of 1.4 should be printed with the dots of three different panels 64K superimposed.

Other forms of ribbon 60 can be obtained with more or less panels in a repeating series. The use of fewer panels results in faster print speeds but reduces the level of step change between the highest and lowest image optical density possible. Using more panels will increase the number of halftone steps that can be obtained, but will reduce the number of prints that can be obtained with that ribbon if the total length of the ribbon is constant. A particularly advantageous form of ribbon 60 is one that produces images that are in the range of optical densities corresponding to uniformly separated CIE L * values.

The thermal transfer medium according to the present invention comprises an elongated strip or base (32, 42, 52, 62), preferably of a material having suitable thermal resistance and good thermal conductivity. is there. An example of a suitable material is a thickness of 3-25 μm and a density of 0.9-1.4 g / [cubic c
m] plastic film, but polyester film is particularly preferred due to thermal resistance, strength and dimensional stability. An appropriately colored thermal transfer ink mixture is coated on the base as a repeating series of adjacent panels to form a thermal transfer ink layer (3
4, 44, 54, 64) are formed.

A suitable basic thermal wax transfer ink mixture comprises 20 to 80 parts by weight binder, 3 to 20 parts by weight softener and 1 part by weight based on the total weight of the ink layer being 100 parts by weight. ˜20 wt.% Coloring agent or colorant may be included. The thickness of the ink layer is typically in the range of about 1-10 μm, more typically about 5-6.
μm.

The binder is composed of a solid wax with a depth of field (at 25 degrees Celsius) of 10 to 30. This solid wax can be used in combination with easily melting substances such as low molecular weight polyethylene, oxide waxes or ester waxes.

The softening agent is an easily heat-melting material such as polyvinyl acetate, polystyrene, styrene-butadiene copolymer, cellulose ester, cellulose ether or acrylic resin, or lubricating oil such as mineral oil.

Finely divided heat transfer materials, extender pigments, or mixtures thereof may be added to the ink mixture to provide a heat sensitive thermal wax transfer ink layer having good heat transfer and melt mobilities. If the weight of all the solids of the ink mixture is 100 parts by weight, 0 to 30 parts by weight of the heat transfer material and 0 to 10 parts by weight of the extender pigment may be used.

Thermal transfer ink layer (34, 44, 54, 6
The melting point of 4) is in the range of 50 to 150 degrees Celsius, and the viscosity is 20 to 10 at a temperature higher than the melting point by 30 degrees Celsius.
It is 000 cP. Melting points in the range of 60 to 80 degrees Celsius are typical. Also, for the transferred ink layer,
At room temperature, rather hard layers are desirable, as soft layers are easily damaged.

The colorant used in the thermal wax transfer ink layer of the media 30, 40, 50 and 60 preferably comprises a dye or pigment of suitable hue which is transparent or translucent (except for the black ink layer). To be done. The colorant is dissolved or dispersed in the ink layer in an amount effective to obtain the desired colorant concentration or saturation level. Examples of yellow pigment coloring agents are Chroma Yellow, Zinc Yellow, Chrome Barium, Cadmium Yellow, Naphthol Yellow S, Hansa Yellow 10G, Hansa Yellow 5G,
Hansa Yellow 3G, Hansa Yellow G, Hansa
Examples include Yellow GR, Hansa Yellow A, Hansa Yellow RN, Hansa Yellow R, Benzidine Yellow, Benzidine Yellow G, Benzidine Yellow GR, Permanent Yellow NCG, and Quinoline Yellow Lake. Examples of yellow dyes include auramine.

Examples of magenta pigments are Permanent Red 4R, Brilliant First Scarlet,
Brilliant Carmine BS, Permanent Carmine FB, Resor Red, Permanent Red F5
R, Brilliant Carmine 6B, Pigment Scarlet 3B, Rhodamine Lake B, Rhodamine Lake Y, and Alizarin Lake. The magenta dye is rhodamine or the like.

Examples of cyan pigments include Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, and First Sky Blue. Examples of cyan dyes include Victoria Blue.

Examples of black colorants are carbon black and nigrosine base.

The illustrated yellow, magenta and cyan pigments or dyes, or other suitable pigments or dyes, are mixed in suitable amounts to provide colorants for the red, green and blue ink layers, or desired spot colors. A colorant for the ink layer can be obtained. Alternatively, a suitable pigment or dye of the desired color may be used. Choosing an appropriate colorant or mixture of colorants for the thermal transfer ink layers of media 30, 40, 50 and 60 can be readily accomplished by one of ordinary skill in the art of manufacturing such media.
Further description is omitted.

When the thermal transfer ribbon of the present invention is used as a recording medium for thermal printing, that is, a printing medium, the ribbon is positioned so that the ink layer faces the recording medium such as a smooth white paper sheet. Printing is performed with a thermal print head that heats the back of the ribbon. In the case of a thermal wax transfer printer, the heat transferred through the ribbon-based film as a ribbon melts the dot-sized areas of the ink layer on the opposite side and maintains a momentary contact with the recording medium. Then, the ribbon and the recording medium are separated, and the melted ink dots are transferred to the recording medium.

In the case of a thermal transfer printer of the dye diffusion (dye sublimation) type, the thermal print head causes the coloring material in the ink layer on the recording medium in an amount corresponding to the amount of thermal energy supplied by the print head. Diffuse into the receiving layer.

This process is performed once for each panel in the series of panels on the ribbon. Thus, for a ribbon 40 having a series of 6 panels of different primary or secondary colors, 6 by the same sheet of recording medium contacting a different panel 44 during each pass of the ribbon over the printhead. The transfer process is executed only once. (The final image is
A color obtained from a combination that includes the colors of the ink in that panel,
That is, an image-dependent pattern of ink dots (if it does not contain a particular color) is transferred from the panel in contact with the recording sheet in each pass. Therefore, the final image is composed of 6 dot patterns overlaid on the same area of the recording medium. Accurate positioning must be maintained, with the recording medium and ribbon together across the printhead multiple times (in this case, six times). Otherwise, color quality will have a large impact.

As can be seen, a dye diffusion printer modulates the heat its print head supplies to the ribbon,
Because different amounts of colorant can be transferred to the recording medium, the embodiments of FIGS. 1 and 4 of the present invention are primarily applicable to thermal wax transfer printing applications. These embodiments are characterized by the ability to produce the same number of colors as a conventional ribbon with smaller dither cells and a wider range of colors than a dither cell of the same size. In addition, ribbons of the type shown in FIGS. 1 and 4 have a less grainy image because the optical contrast between individual ink dots and their background (recording medium) is reduced in the image area due to dither. To occur.

Further, each embodiment of the present invention includes an additional panel of suitable precoat material within each panel of the series (ie, the series B, C, D or E) of that series of sets. A precoat layer may be supplied to the recording medium before the colorant is transferred from the ink layer inside. This precoat layer allows for improved printing on plain paper, or other media with a relatively rough surface. Further, in the case of dye diffusion printing, it is possible to print on an uncoated recording medium. Thermal transfer print with panels of pre-coated material
Ribbons are, for example, US Pat. Nos. 4,527,171, 4,
No. 704615 and 5116148.

It will be understood that the various preferred embodiments of the invention described above are not meant to limit the scope of the invention to these particulars, and various modifications without departing from the scope of the invention. Can be modified and changed.

[0041]

The thermal transfer print media (ribbons) according to the invention can reproduce colors with improved resolution and image fidelity by printing a wider range of colors or color intensities without dithering.

[Brief description of drawings]

FIG. 1 is a partial plan view of a thermal transfer print medium according to a first embodiment of the present invention.

FIG. 2 is a partial plan view of a thermal transfer print medium according to a second embodiment of the present invention.

FIG. 3 is a partial plan view of a thermal transfer print medium according to a third embodiment of the present invention.

FIG. 4 is a partial plan view of a thermal transfer print medium according to a fourth embodiment of the present invention.

FIG. 5 is a plan view of a conventional thermal wax transfer ribbon.

6 is a sectional view taken along the line II-II in FIG.

[Explanation of symbols]

 30 thermal transfer ribbon (thermal transfer print medium) 32 base (base) 34 ink layer

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Patrick E Wellborn Oregon, USA 97035 Lake Oswego South West Charit Way 17781

Claims (3)

[Claims] 1. A base sheet and a plurality of different thermal inks provided in a plurality of coating regions of the base sheet, the plurality of thermal inks having the same hue but different saturation levels. A thermal transfer print medium characterized by the above. 2. A base sheet, and a plurality of different substantially transparent heat-sensitive inks provided in a plurality of coating regions of the base sheet, wherein the hues of the plurality of heat-sensitive inks are two different first and second hues. A thermal transfer print medium having a hue and a third hue corresponding to the hue obtained by combining the first and second hues. 3. A base sheet, and a plurality of different thermal inks provided in a plurality of coating regions of the base sheet, the plurality of thermal inks being inks of two different primary colors,
A thermal transfer print medium comprising an ink of a hue other than the primary colors.